KR102100519B1 - Processes to produce short cut microfibers - Google Patents

Abstract

(A) contacting the cut multi-component fibers having a length of less than 25 mm in the fiber slurry zone with the treated aqueous stream to produce a cut multi-component fiber slurry; (B) contacting the cut multicomponent fiber slurry with a heated aqueous stream in a mixing zone to produce a heated slurry; (C) sending the heated multi-component fiber slurry to a fiber open zone to remove a portion of the water-dispersible sulfopolyester to produce an open microfiber slurry; And (D) sending the open microfiber slurry to a first solid-liquid separation zone to produce a microfiber product stream and a first mother liquor stream.

Description

Manufacturing method of short-cut microfibers {PROCESSES TO PRODUCE SHORT CUT MICROFIBERS}

The present invention relates to water dispersible fibers and fiber articles comprising sulfopolyesters. The present invention also relates to multicomponent fibers comprising sulfopolyesters, and microdenier fibers and fiber articles made therefrom. The invention also relates to a process for the production of water-dispersible multicomponent fibers and microdenier fibers and articles made therefrom.

This application claims priority to U.S. Provisional Application Nos. 61 / 592,854, 61 / 592,867, 61 / 592,917, and 61 / 592,974, filed January 31, 2012, the disclosures of which are incorporated herein by reference. It is incorporated herein by reference to the extent that it does not contradict the description.

Fibers, meltblown webs and other melt spun fiber articles have been made from thermoplastic polymers such as poly (propylene), polyamides and polyesters. One common use of these fibers and textile articles is, inter alia, wipes, feminine hygiene articles, baby diapers, adult incontinence briefs, hospital / surgical and other medical disposable protective fabrics and layers, geotextiles. , Industrial wipes, and nonwovens in personal care articles such as filter media. Unfortunately, personal care articles made from conventional thermoplastic polymers are difficult to discard and are usually discarded in landfills. One promising alternative disposal method is to make these articles or their components “washable”, ie suitable for public sewage systems. The use of water-dispersible or water-soluble materials also improves the recyclability and regeneration of personal care articles. The various thermoplastic polymers currently used in personal care articles are not inherently water dispersible or water soluble, and therefore do not produce articles that can be easily dismantled and disposed of in a sewage system or easily recycled.

Due to the demand for washable personal care articles, there has been a need for fibers, nonwovens and other fibrous articles having various water-reactivity rates. Various solutions to address this need are described, for example, in U.S. Patent Nos. 6,548,592, 6,552,162, 5,281,306, 5,292,581, 5,935,880 and 5,509,913; US Patent Application Nos. 09 / 775,312 and 09 / 752,017; And PCT International Patent Publication WO 01/666666 A2. However, these solutions have several drawbacks and do not provide a textile article, such as a fiber or non-woven fabric, with a satisfactory balance of tensile strength, absorbency, flexibility, and performance characteristics such as fabric integrity under wet or dry conditions.

For example, a typical non-woven technique is based on depositing fibers treated with a resin-bonded adhesive in multiple directions to produce a web with strong integrity and other desirable properties. However, the resulting assembly generally has poor water-reactivity and is not suitable for washable applications. The presence of the binder can also cause undesirable properties of the final article, such as reduced sheet wettability, increased stiffness, blocking properties and higher manufacturing cost. It is also difficult to prepare a binder that exhibits adequate wet strength during use but disperses quickly upon disposal. Accordingly, the nonwoven assembly using such a binder may be gradually dismantled under ambient conditions or may have a wet strength property of less than an appropriate degree in the presence of body fluids. To address this problem, pH and ion-sensitive water-dispersible binders, such as lattices containing acrylic or methacrylic acid, with or without salts, are known and described, for example, in US Pat. No. 6,548,592 B1. . However, ionic concentrations and pH levels in public sewage and residential purification systems may vary widely depending on geographic location and the binder may not be soluble and sufficient to disperse. In this case, the fibrous article may not be dismantled after disposal, and the drain pipe or sewer pipe may be blocked.

Multicomponent fibers containing water dispersible components and thermoplastic water non-dispersible components are described, for example, in U.S. Pat.Nos. 5,916,678, 5,405,698, 4,966,808, 5,525,282, 5,366,804, 5,486,418. For example, these multicomponent fibers can be molded or shaped, for example, islands-in-the-sea, sheath core, side-by-side or segmented pie shapes. It can be a bicomponent fiber having an engineered cross section. By adding water or a dilute alkaline solution to the multi-component fiber, the water-dispersible component can be dissolved to leave the water non-dispersible component as a separate, independent fiber of extremely small fineness. However, polymers with good water dispersibility often give stickiness to the resulting multicomponent fibers, allowing the fibers to stick together, block or fuse with each other during coiling or after several days of storage, especially under high temperature and high humidity conditions. In order to prevent fusion, a fatty acid or oil-based final treatment agent is often applied to the fiber surface. In addition, large amounts of pigments or fillers are sometimes added to the water-dispersible polymer to prevent fusion of the fibers, as described, for example, in US Pat. No. 6,171,685. These oil finishes, pigments and fillers require additional processing steps and can impart undesirable properties to the final fiber. Many water-dispersible polymers also require alkaline solutions to remove them, which can cause deterioration of other polymer components of the fiber, such as, for example, reduction in intrinsic viscosity, toughness and melt strength. In addition, some water-dispersible polymers cannot withstand exposure to water during high-pressure hydroentanglement and are therefore unsuitable for the production of nonwoven webs and nonwovens.

Alternatively, the water dispersible component can serve as a binder for thermoplastic fibers in the nonwoven web. Upon exposure to water, the fiber-fiber bonds are separated such that the nonwoven web loses its integrity and breaks up into individual fibers. However, the thermoplastic fiber component of these nonwoven webs is not water dispersible and remains in an aqueous medium, and must eventually be removed from urban wastewater treatment plants. High pressure weaving can be used to produce degradable nonwovens with or without very low levels (less than 5% by weight) of binder added to keep the fibers together. Although these fabrics can be dismantled upon disposal, they often use fibers that are not water soluble or water dispersible and can cause entanglement and clogging within the sewage system. Any added water-dispersible binder should also be minimally affected by high-pressure weaving, and should not form gelatinous or crosslinked compounds, thereby contributing to fabric handling or sewer related issues.

Several water soluble or water dispersible polymers are available, but are typically not applicable to melt blown fiber manufacturing processes or melt spinning. Polymers such as polyvinyl alcohol, polyvinyl pyrrolidone and polyacrylic acid cannot be melt processed due to thermal decomposition occurring at a temperature below which a suitable melt viscosity is achieved. High molecular weight polyethylene oxide may have suitable thermal stability, but provides a high viscosity solution at the polymer interface to slow the rate of disintegration. Water-dispersible sulfopolyesters are described, for example, in U.S. Pat.Nos. 6,171,685, 5,543,488, 5,853,701, 4,304,901, 6,211,309, 5,570,605, 6,428,900 and 3,779,993. However, typical sulfopolyesters are low molecular weight thermoplastics that lack the flexibility to withstand winding operations to obtain rolls of brittle, unbreakable or unbreakable material. Sulfopolyesters may also exhibit blocking or fusing during processing into a film or fiber, which may require the use of oil finishes or large amounts of pigments or fillers to avoid this. Low molecular weight polyethylene oxide (more commonly known as polyethylene glycol) is a weak / fragile polymer that does not have the physical properties required for fiber applications. There is an alternative to making fibers from known water-soluble polymers via solution techniques, but the added complexity of removing solvents (especially water) adds to the manufacturing cost.

Accordingly, there is a need for water-dispersible fibers and textile articles made therefrom that exhibit fabric integrity in the presence of adequate tensile strength, absorbency, flexibility, and moisture, particularly when exposed to human body fluids. There is also a need for a textile article that does not require a binder and that disperses or dissolves completely in residential or municipal sewage systems. Possible uses include melt blown webs, spunbonded fabrics, high pressure woven fabrics, dry-laid nonwovens, bicomponent fiber components, adhesion promoting layers, binders for cellulose, washable nonwovens and films , Soluble binder fibers, protective layers, and carriers for active ingredients that are released or dissolved in water. There is also a need for a multicomponent fiber that exhibits no excessive blocking or fusing of the filament during spinning operations and is easily removed by hot water at neutral or slightly acidic pH and has a water dispersible component suitable for high water pressure weaving processes to produce nonwovens. Other fiber materials that are extrudable and melt spun are also possible.

The inventors unexpectedly discovered that flexible water-dispersible fibers can be prepared from sulfopolyesters. Therefore, the present invention

(A) (i) one or more dicarboxylic acid residues; (ii) about 4 to about 40 mole percent, based on total repeating units, of at least one functional group attached to an aromatic or cycloaliphatic ring (which is hydroxyl, carboxyl, or combinations thereof) and at least one sulfonate group Sulfomonomer residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (iv) from 0 to about 25 mole percent, based on total repeat units, of a branched monomer residue having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), a glass transition temperature of 25 ° C. or higher. Sulfopolyester having (Tg);

(B) optionally, a water dispersible polymer blended with the sulfopolyester; And

(C) Optionally, a water non-dispersible polymer blended with the sulfopolyester, provided that the blend is an immiscible blend.

It provides a water-dispersible fiber containing less than 10% by weight of a pigment or filler based on the total weight of the fiber.

The fibers of the present invention can be monocomponent fibers that are readily dispersed or dissolved in water and can be prepared by melt-blowing or melt-spinning. The fibers can be made from a single sulfopolyester, or a blend of a sulfopolyester with a water dispersible or water non-dispersible polymer. Accordingly, the fibers of the present invention may optionally include a water-dispersible polymer blended with sulfopolyester. In addition, the fibers may optionally include a water non-dispersible polymer blended with sulfopolyester, provided that the blend is an immiscible blend. The present invention also includes fiber articles comprising the water-dispersible fibers of the present invention. Thus, using the fibers of the present invention, it is possible to produce a variety of textile articles (which are either water dispersible or washable), such as yarns, melt-blown webs, spin-bonded webs and nonwovens. The staple fibers of the present invention can also be blended with natural or synthetic fibers in paper, nonwoven webs and textile yarns.

Another aspect of the invention

(A) (i) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues; (ii) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; (iv) a glass transition temperature of at least 25 ° C., comprising from 0 to about 20 mole percent, based on total repeat units, of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof) Sulfopolyester with Tg);

(B) optionally, a first water-dispersible polymer blended with the sulfopolyester; And

(C) optionally, a water non-dispersible polymer blended with the sulfopolyester to form an immiscible blend.

It is a water-dispersible fiber, containing less than 10% by weight of pigment or filler, based on the total weight of the fiber.

The water-dispersible fibrous articles of the present invention include personal care articles such as wipes, gauze, tissues, diapers, training pants, sanitary napkins, bandages, wound care and surgical dressings. In addition to being water dispersible, the textile article of the present invention is washable, ie compatible with residential and urban sewage systems and suitable for disposal in the sewage system.

The invention also provides multicomponent fibers comprising a water dispersible sulfopolyester and one or more water non-dispersible polymers. This fiber has a geometric shape designed to allow the water non-dispersible polymers to exist as substantially isolated compartments from each other by intervening sulfopolyesters, the sulfopolyester being a binder to the water non-dispersible compartment or It acts as a surrounding matrix. Accordingly, another aspect of the present invention

(A) (i) one or more dicarboxylic acid residues; (ii) about 4 to about 40 mole percent, based on total repeating units, of at least one functional group attached to an aromatic or cycloaliphatic ring (which is hydroxyl, carboxyl, or combinations thereof) and at least one sulfonate group Sulfomonomer residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (iv) from 0 to about 25 mole percent, based on total repeating units, of a branched monomer residue having 3 or more functional groups, which are hydroxyl, carboxyl, or combinations thereof, at a glass transition temperature of at least 57 ° C. Water-dispersible sulfopolyester having (Tg); And

(B) a plurality of segments comprising one or more water non-dispersible polymers immiscible with the sulfopolyester, the compartments being substantially isolated from each other by the sulfopolyester intervening between the compartments With multiple compartments

It is a multi-component fiber having a molded cross-section, including.

The sulfopolyester has a glass transition temperature of 57 ° C. or higher, which significantly reduces the blocking and fusing of fibers during winding and long-term storage. The sulfopolyester can be removed by contacting the multicomponent fiber with water, leaving the water non-dispersible compartments as microdenier fibers. Therefore, the present invention also

(A) (i) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues; (ii) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (iv) from 0 to about 20 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units, and having a glass transition temperature of 57 ° C. or higher ( Spinning a water dispersible sulfopolyester having Tg), and at least one water non-dispersible polymer that is immiscible with the sulfopolyester into a multicomponent fiber, wherein the fiber comprises a water non-dispersible polymer. Having a plurality of compartments, the compartments being substantially isolated from each other by a sulfopolyester intervening between the compartments; And

(B) generating micro-denier fibers by removing the sulfopolyester by contacting the multicomponent fibers with water.

It also provides a method for producing a microdenier fiber, including.

The water non-dispersible polymer can be biodisintegratable as determined by DIN standard 54900 and / or biodegradable as determined by ASTM standard method D6340-98. The multicomponent fibers can also be used to make textile articles such as yarns, fabrics, melt-blown webs, spin-bonded webs or nonwovens (which may include one or more layers of fibers). A fibrous article with multicomponent fibers can then be contacted with water to produce a fibrous article containing microdenier fibers.

Accordingly, another aspect of the present invention

(A) (i) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues; (ii) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (iv) from 0 to about 20 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units, and having a glass transition temperature of 57 ° C. or higher ( Spinning a water dispersible sulfopolyester having Tg), and at least one water non-dispersible polymer that is immiscible with the sulfopolyester into a multicomponent fiber, wherein the fiber comprises a water non-dispersible polymer. Having a plurality of compartments, the compartments being substantially isolated from each other by a sulfopolyester intervening between the compartments;

(B) collecting the multicomponent fibers of step (A) by overlapping to produce a nonwoven web; And

(C) generating a microdenier fiber web by removing the sulfopolyester by contacting the nonwoven web with water.

It is a method of manufacturing a microdenier fiber web comprising a.

The present invention also

(A) (i) (a) one or more dicarboxylic acid residues; (b) about 4 to about 40 mole percent, based on total repeat units, of one having two functional groups attached to an aromatic or cycloaliphatic ring (which is hydroxyl, carboxyl, or combinations thereof) and one or more metal sulfonate groups The above sulfomonomer residues; (c) At least 20 mol% based on the total diol residue is poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (d) from 0 to about 25 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units, at 25 ° C. or higher. Sulfopolyester having (Tg);

(ii) optionally, a water dispersible polymer blended with the sulfopolyester; And

(iii) optionally, a water non-dispersible polymer blended with the sulfopolyester to produce an immiscible blend.

And heating the water-dispersible polymer composition containing less than 10% by weight of pigment or filler based on the total weight of the polymer composition to a temperature above its pour point;

(B) melt spinning the filament; And

(C) collecting the filaments of step (B) overlapping to create a nonwoven web

It also provides a method for producing a water-dispersible nonwoven fabric comprising a.

In another aspect of the invention,

(A) shows a melt viscosity of less than about 12,000 poise, measured at 240 ° C. at a strain rate of 1 radian / second, and less than about 25 mole percent of one or more sulfomonomer residues based on the total moles of diacid or diol residues. Comprising, one or more water-dispersible sulfopolyesters; And

(B) a plurality of microfiber domains comprising one or more water non-dispersible polymers immiscible with the sulfopolyesters, the domains being substantially isolated from each other by a sulfopolyester intervening between the domains, Multiple microfiber domains

Multicomponent fibers having a molded cross-section are provided.

In another aspect of the invention,

(A) one or more water-dispersible sulfopolyesters; And

(B) a plurality of domains comprising one or more water non-dispersible polymers immiscible with the sulfopolyester, the domains being substantially isolated from each other by a sulfopolyester intervening between the domains. domain

A multi-component extrudate having a molded cross section is provided, comprising:

At this time, the extrudate may be melt drawn at a speed of about 2000 m / min or more.

In another aspect of the invention, a method of making a multicomponent fiber having a shaped cross-section, comprising spinning one or more water dispersible sulfopolyesters and one or more water non-dispersible polymers immiscible with the sulfopolyester. Is provided,

In this case, the multi-component fiber has a plurality of domains including a water non-dispersible polymer, and these domains are substantially isolated from each other by a sulfopolyester intervening between the domains, and the water-dispersible sulfopolyester is 1 radian. A melt viscosity of less than about 12,000 poise as measured at 240 ° C. at a strain rate of / sec and comprises less than about 25 mole percent of one or more sulfomonomer residues based on the total moles of diacid or diol residues.

In another aspect of the invention,

Extruding one or more water dispersible sulfopolyesters and one or more water non-dispersible polymers immiscible with the sulfopolyester to produce a multicomponent extrudate, wherein the multicomponent extrudate is the water non-dispersible A step having a plurality of domains comprising a polymer, the domains being substantially isolated from each other by the sulfopolyester intervening between the domains, and

Melt drawing the multi-component extrudate at a rate of about 2000 m / min or more to produce multi-component fibers.

A method of manufacturing a multicomponent fiber having a molded cross-section is provided.

In another aspect, the present invention

(A) spinning at least one water dispersible sulfopolyester and at least one water non-dispersible polymer that is immiscible with the water dispersible sulfopolyester into multicomponent fibers, wherein the multicomponent fibers are water non-dispersible. Having a plurality of domains comprising a polymer, the domains are substantially isolated from each other by a sulfopolyester intervening between the domains, and the water-dispersible sulfopolyester is measured at 240 ° C. at a strain rate of 1 radian / second. A step having a melt viscosity of less than about 12,000 poise and comprising less than about 25 mole percent of one or more sulfomonomer residues based on the total moles of diacid or diol residues, and

(B) contacting the multicomponent fiber with water to remove the water dispersible sulfopolyester to produce microdenier fibers of the water non-dispersible polymer (s).

It provides a method for producing a micro-denier fiber comprising a.

In another aspect, the present invention

(A) extruding at least one water dispersible sulfopolyester and at least one water non-dispersible polymer that is immiscible with the water dispersible sulfopolyester to produce a multicomponent extrudate, wherein the multicomponent extrudate is -Having a plurality of domains comprising a dispersible polymer, said domains being substantially isolated from each other by a sulfopolyester intervening between the domains;

(B) producing a multi-component fiber by melt drawing the multi-component extrudate at a rate of about 2000 m / min or more; And

(C) contacting the multicomponent fiber with water to remove the water dispersible sulfopolyester to produce microdenier fibers of the water non-dispersible polymer (s).

It provides a method for producing a micro-denier fiber comprising a.

In another aspect of the invention,

(A) spinning at least one water dispersible sulfopolyester and at least one water non-dispersible polymer immiscible with the sulfopolyester into multicomponent fibers, wherein the multicomponent fibers comprise water non-dispersible polymers. Has a plurality of domains, the domains are substantially isolated from each other by the water-dispersible sulfopolyester intervening between the domains, and the water-dispersible sulfopolyester is about 1 when measured at a strain rate of 1 radian / sec. Having a melt viscosity of less than 12,000 poise and comprising less than about 25 mole percent of one or more sulfomonomer residues based on the total moles of diacid or diol residues;

(B) collecting the multicomponent fibers of step (A) to produce a nonwoven web; And

(C) generating a microdenier fiber web by removing the sulfopolyester by contacting the nonwoven web with water.

A method of manufacturing a microdenier fiber web comprising a.

In another aspect of the invention,

(A) extruding one or more water dispersible sulfopolyesters and one or more water non-dispersible polymers immiscible with sulfopolyester to produce a multicomponent extrudate, wherein the multicomponent extrudate is water non-minute Having a plurality of domains comprising an acidic polymer, the domains being substantially isolated from each other by a sulfopolyester intervening between the domains;

(B) producing a multi-component fiber by melt drawing the multi-component extrudate at a speed of about 2000 m / min or more;

(C) collecting the multicomponent fibers of step (B) to produce a nonwoven web; And

(D) generating a microdenier fiber web by removing the sulfopolyester by contacting the nonwoven web with water.

A method of manufacturing a microdenier fiber web comprising a.

In another embodiment of the invention,

(A) cutting the multicomponent fiber into cut multicomponent fibers;

(B) contacting the fiber-containing feedstock comprising the cut multicomponent fibers with water to produce a fiber mixing slurry;

(C) heating the fiber mixing slurry to produce a heated fiber mixing slurry;

(D) optionally, mixing the fiber mixing slurry in a shear zone;

(E) removing at least a portion of the sulfopolyester from the cut multicomponent fiber to produce a slurry mixture comprising the sulfopolyester dispersion and the cut water non-dispersible polymer microfibers; And

(F) separating the cut water non-dispersible polymer microfibers from the slurry mixture.

A method of making a cut water non-dispersible polymer microfiber, comprising: is provided.

In another embodiment of the present invention, a cut water non-dispersible polymer microfiber comprising at least one water non-dispersible polymer is provided, wherein the cut water non-dispersible polymer microfiber is less than 5 microns. Has an equivalent diameter of less than 25 mm.

In another embodiment of the present invention, there is provided a method of making a non-woven article from the water non-dispersible polymer microfiber, the method

(A) providing a water non-dispersible polymer microfiber made from multicomponent fibers; And

(B) manufacturing a nonwoven article using a wet-laid process or a dry-laid process

It includes.

In another embodiment of the invention, a method of making a microfiber product stream is provided. This way

(A) contacting a short-cut multicomponent fiber having a length of less than 25 mm with a heated aqueous stream in a fiber opening zone to remove a portion of the water-dispersible sulfopolyester to produce an open microfiber slurry, wherein the The short-cut multicomponent fiber comprises at least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester, wherein the heated aqueous stream is at a temperature of 40 ° C. or higher, The open microfiber slurry comprising water, microfiber and water dispersible sulfopolyester; And

(B) sending the open microfiber slurry to a first solid-liquid separation zone to produce a microfiber product stream and a first mother liquor stream, wherein the first mother liquor stream comprises water and a water dispersible sulfopolyester. , step

It includes.

In another embodiment of the present invention, a method for producing a microfiber product stream is provided, the method

(A) contacting a short-cut multicomponent fiber having a length of less than 25 mm with a heated aqueous stream in a fiber opening zone to remove a portion of the water-dispersible sulfopolyester to produce an open microfiber slurry, wherein the The short-cut multicomponent fiber comprises at least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester, wherein the heated aqueous stream is at a temperature of 40 ° C. or higher, The open microfiber slurry comprising water non-dispersible polymer microfibers, water dispersible sulfopolyester and water; And

(B) sending the open microfiber slurry to a first solid-liquid separation zone to produce a microfiber product stream and a first mother liquor stream, wherein the first mother liquor stream comprises water and a water dispersible sulfopolyester. , step

It includes.

In another embodiment of the present invention, a method for producing a microfiber product stream is provided, the method

(A) contacting the short-cut multi-component fiber having a length of less than 25 mm with the aqueous stream treated in the fiber slurry zone to produce a short-cut multi-component fiber slurry, wherein the short-cut multi-component fiber is one. At least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester, wherein the treated aqueous stream is at a temperature of at least 40 ° C .;

(B) contacting the short-cut multi-component fiber slurry and the heated aqueous stream in a fiber open zone to remove a portion of the water-dispersible sulfopolyester to produce an open microfiber slurry, wherein the open microfiber The slurry comprises water non-dispersible polymer microfibers, water dispersible sulfopolyester and water; And

(C) sending the open microfiber slurry to a first solid-liquid separation zone to produce a microfiber product stream and a first mother liquor stream, wherein the first mother liquor stream comprises water and a water dispersible sulfopolyester. , step

It includes.

In another embodiment of the present invention, another method for producing a microfiber product stream is provided, the method comprising

(A) contacting a short-cut multi-component fiber having a length of less than 25 mm in a mixing zone with a heated aqueous stream to produce a short-cut multi-component fiber slurry, wherein the short-cut multi-component fibers are one or more A water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester, wherein the heated aqueous stream is at a temperature of 40 ° C. or higher;

(B) the short-cut multicomponent fiber slurry, and optionally, sending a heated aqueous stream to a fiber open zone to remove a portion of the water dispersible sulfopolyester to produce an open microfiber slurry, wherein The open microfiber slurry comprising water non-dispersible polymer microfibers, water dispersible sulfopolyester and water; And

(C) sending the open microfiber slurry to a first solid-liquid separation zone to produce a microfiber product stream and a first mother liquor stream, wherein the first mother liquor stream comprises water and a water dispersible sulfopolyester. , step

It includes.

In another embodiment of the present invention, another method for producing a microfiber product stream is provided, the method comprising

(A) contacting a short-cut multi-component fiber having a length of less than 25 mm in a fiber slurry zone with a treated aqueous stream to produce a short-cut multi-component fiber slurry, wherein the short-cut multi-component fiber is one. At least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester, wherein the treated aqueous stream is at a temperature of at least 40 ° C .;

(B) contacting the short-cut multicomponent fiber slurry with a heated aqueous stream in a mixing zone to produce a heated multicomponent fiber slurry;

(C) sending the heated multi-component fiber slurry to a fiber open zone to remove a portion of the water-dispersible sulfopolyester to produce an open microfiber slurry; And

(D) sending the open microfiber slurry to a first solid-liquid separation zone to produce a microfiber product stream and a first mother liquor stream, wherein the first mother liquor stream comprises water and a water dispersible sulfopolyester. , step

It includes.

In another embodiment of the present invention, a method of separating a first mother liquor stream is provided. The method includes sending a first mother liquor stream to a second solid-liquid separation zone to produce a second wet cake stream and a second mother liquor stream, wherein the second mother liquor stream comprises water and water dispersible sulfopolyester. And the second wet cake stream comprises water non-dispersible polymer microfibers.

In another embodiment of the invention, a method of recovering sulfopolyester is provided. This way,

(A) sending a second mother liquor stream to the first concentration zone to produce a first polymer concentrate stream and a first recovered water stream; And

(B) optionally, sending the first recovered water stream to the fiber open area

It includes.

1A, 1B, and 1C are cross-sectional views of three differently constructed fibers, particularly illustrating how to determine various measurements related to fiber size and shape.
2 illustrates an embodiment of the invention in which a microfiber product stream is produced in a one stage open zone.
3A and 3B illustrate embodiments of the invention in which a microfiber product stream is produced in a two stage open zone.
4 illustrates an embodiment of the invention in which a microfiber product stream is produced in a three stage open zone.
5 illustrates an embodiment of a method of cutting a multicomponent fiber to produce a short-cut multicomponent fiber.
6A illustrates an embodiment of an open band comprising pipes.
6B illustrates an embodiment of an open zone comprising a continuously stirred tank.
6C illustrates an embodiment of an open zone comprising more than one continuously stirred tank.
7A and 7B illustrate embodiments of the first solid-liquid separation zone.
8 shows the change in solids in the first mother liquor recovered from the opening process of Example 36.
Figure 9 shows the results of performing the 37 INS bicomponent fiber opening process according to Example 38.
FIG. 10 shows the sulfopolyester content in the first mother liquor in the open process according to Example 39 as a function of treatment time.
11 shows the rate of sulfopolyester removal in the open process according to Comparative Example 40.
FIG. 12 shows the sulfopolyester removal profile for fiber opening according to Comparative Example 41.

The present invention provides water-dispersible fibers and fibrous articles that exhibit fabric integrity, especially when exposed to human body fluids in the presence of tensile strength, absorbency, flexibility, and moisture. The fibers and fibrous articles of the present invention do not require the presence of oil, wax or fatty acid final treatment agents, or the use of large amounts (typically at least 10% by weight) of pigments or fillers to prevent blocking or fusing of the fibers during processing. Does not. In addition, fiber articles made from the novel fibers of the present invention do not require a binder and are easily dispersed or dissolved in home or public sewage systems.

In a comprehensive embodiment, the present invention is a water dispersible fiber comprising a sulfopolyester having a glass transition temperature (Tg) of 25 ° C. or higher, wherein the sulfopolyester is

(A) one or more dicarboxylic acid residues;

(B) about 4 to about 40 mole percent, based on total repeating units, of at least one functional group attached to the aromatic or cycloaliphatic ring (which is hydroxyl, carboxyl, or combinations thereof) and at least one sulfonate group. Sulfomonomer residues;

(C) At least 25 mol% based on the total diol residue is poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And

(D) 0 to about 25 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units

It provides a water-dispersible fiber comprising a.

The fibers of the present invention may optionally include a water-dispersible polymer blended with a sulfopolyester, and optionally a water non-dispersible polymer blended with a sulfopolyester, provided that the blend is an immiscible blend. You can. The present invention also includes textile articles comprising these fibers, and may include personal care articles such as wipes, gauze, tissues, diapers, adult incontinence briefs, bowel training pants, sanitary napkins, bandages, and surgical dressings. The fibrous article can have one or more absorbent fibrous layers.

The fibers of the present invention may be monocomponent fibers, bicomponent fibers or multicomponent fibers. For example, the fibers of the present invention can be made by melt spinning a single sulfopolyester or a sulfopolyester blend, and include staple fibers, single filament fibers and multifilament fibers having a shaped cross section. In addition, the present invention provides multicomponent fibers such as those described in U.S. Patent No. 5,916,678, which have shaped or engineered transverse geometries such as, for example, "sea charts", sheath-cores, parallel or divided pie shapes. It can be prepared by separately extruding sulfopolyesters and one or more water non-dispersible polymers immiscible with sulfopolyesters through spinnerets. The sulfopolyester can be subsequently removed by dissolving the interfacial layer or pi compartment, leaving smaller filaments or microdenier fibers of the water non-dispersible polymer (s). These water non-dispersible polymer fibers have a much smaller fiber size than the multicomponent fibers prior to removing the sulfopolyester. For example, sulfopolyesters and water non-dispersible polymers can be supplied to a polymer distribution system that introduces the polymer into a divided spinneret plate. The polymer follows a separate path to the fiber spinneret, spinneret holes that provide sheath-core type fibers, including two concentric circular holes, or split into multiple parts along a diameter to form parallel fibers. Merging from the provided circular spinneret holes. Alternatively, the immiscible water-dispersible sulfopolyester and water non-dispersible polymer can be introduced separately into a spinneret having a plurality of radial channels to produce multicomponent fibers having a divided pie cross section. Typically, the sulfopolyester forms a “shell” component in the shape of a shell core. In the cross section of a fiber having a plurality of compartments, the water non-dispersible compartments are typically substantially isolated from each other by sulfopolyester. Alternatively, fibers having a cross-section of shape can be obtained by melting the sulfopolyester and the water non-dispersible polymer in separate extruders and flowing the polymer into one spinneret having a plurality of small, thin tube or compartmental distribution flow paths. Multicomponent fibers can be produced by providing. Examples of such spinnerets are described in US Pat. No. 5,366,804. In the present invention, the sulfopolyester typically forms the “sea” component and the water non-dispersible polymer forms the “island” component.

Unless otherwise indicated, numbers expressing amounts of components, properties such as molecular weight, reaction conditions, and the like, as used in the description and claims, are to be understood as being modified in all cases to the term "about". Thus, unless indicated otherwise, the numerical parameters set forth in the following description and appended claims are approximations that may vary depending on the desired properties desired to be obtained by the present invention. At the very least, each numerical parameter should be inferred in light of the reported significant number of figures, and by applying conventional estimation techniques. Also, the scope recited in this description and claims is intended to specifically cover the entire scope, not just the termination value (s). For example, ranges referred to as 0 to 10 include all integers between 0 and 10, such as 1, 2, 3, 4, etc., all decimal numbers between 0 and 10, such as 1.5, 2.3, 4.57, 6.1113, etc. And termination values 0 and 10. Furthermore, the ranges involved with chemical substituents, for example "C1 to C5 hydrocarbons" are intended to specifically include and disclose C1 and C5 hydrocarbons as well as C2, C3 and C4 hydrocarbons.

Although the numerical ranges and parameters describing the broad scope of the present invention are approximate values, the numerical values described in the specific examples are reported as precisely as possible. However, any numerical value implicitly contains certain errors that inevitably arise from standard deviations found in individual test measurements.

The monocomponent fibers and fibrous articles of the present invention are water dispersible and are typically completely dispersed at room temperature. Higher water temperatures can be used to accelerate their dispersion or removal rate from nonwoven or multicomponent fibers. The term "water dispersible" as used herein in reference to monocomponent fibers and fiber articles made from monocomponent fibers is the terms "water-dissipatable", "water-dissipable", "water-soluble" , Synonymous with "water-dispellable", "water-soluble", "water-removable", "hydro-soluble" and "hydrodispersible", textile or fiber articles It is intended to mean that it is dispersed or dissolved in or through the action of water. The terms "dispersed", "dispersible", "dispersed" or "dissipative" are deionized water in an amount sufficient to form a loose suspension or slurry of fibers or fibrous articles within 5 days at about 60 ° C (eg 100 Using: 1 water: fiber, by weight), a plurality of scattered pieces distributed throughout the medium to prevent retrievable filaments from the medium when fibre or fibrous articles are removed, such as by filtration or evaporation, or It means dissolving, dissolving or separating into particles. Thus, as used herein, “water dispersible” is a simple disassembly of an assembly of entangled or bound, but non-water soluble or non-dispersible fibers (in this case, the fiber assembly can simply be broken off in water and recovered by removal of water) It does not contain a slurry of fibers in water). In the context of the present invention, these terms all refer to the action of water or a mixture of water and a water-miscible cosolvent on the sulfopolyesters described herein. Examples of such water-miscible co-solvents include alcohols, ketones, glycol ethers, esters, and the like. The term is intended to include the state in which the sulfopolyester is dissolved to produce a true solution and the state in which the sulfopolyester is dispersed in an aqueous medium. Often, due to the statistical properties of the sulfopolyester composition, a single sulfopolyester sample can have soluble and dispersed fractions when placed in an aqueous medium.

Similarly, the term "water-dispersible" as used herein with respect to sulfopolyesters as a component of a multi-component fiber or textile article also refers to the terms "water-dissipative", "water-dissociable", "water-soluble", Synonymous with "water-monoplastic", "water-soluble", "water-removable", "aqueous-soluble" and "aqueous-dispersible", the sulfopolyester component is sufficiently removed from the multicomponent fiber by the action of water It is intended to mean that it can disperse or dissolve to release and separate the water non-dispersible fibers contained therein. The terms "dispersed", "dispersible", "dispersed", or "dissipative" are sufficient amounts of deionized water to form a loose suspension or slurry of the fiber or fibrous article within 5 days at about 60 ° C ( For example, using 100: 1 water: fiber, by weight) means dissolving, dissolving or separating the sulfopolyester component from the multicomponent fiber, leaving a plurality of microdenier fibers from the water non-dispersible compartment.

The term “compartment” or “domain” or “band” when used to describe a shaped cross-section of a multicomponent fiber refers to a compartment within a cross-section comprising a number of non-dispersible polymers, these domains or compartments being compartments or domains It is substantially isolated from each other by the water-dispersible sulfopolyester intervening therebetween. As used herein, the term “substantially isolated” means that the compartments or domains are spaced apart from each other, such that upon removal of the sulfopolyester, the compartments or domains can form individual fibers. The compartments or domains or zones can be of similar size and shape, or of varying size and shape. Again, the compartments or domains or zones can be arranged in any shape. These compartments or domains or zones are “substantially continuous” along the length of the multicomponent extrudate or fiber. The term "substantially continuous" means continuous along a length of 10 cm or more of a multicomponent fiber. The compartments, domains or zones of the multicomponent fiber produce water non-dispersible polymer microfibers when the water dispersible sulfopolyester is removed.

As mentioned in the detailed description, the molded cross-section of a multicomponent fiber can be in the form of, for example, a sheath-core, a sea chart, a split pie, a hollow split pie, an off-center split pie, and the like.

The water-dispersible fibers of the present invention are made from polyesters, more specifically sulfopolyesters comprising dicarboxylic acid monomer residues, sulfomonomer residues, diol monomer residues and repeat units. The sulfomonomer may be a dicarboxylic acid, diol or hydroxycarboxylic acid. Thus, the term "monomer residue" as used herein means a dicarboxylic acid, diol or hydroxycarboxylic acid residue. As used herein, "repeating unit" refers to an organic structure having two monomeric residues bound through a carbonyloxy group. The sulfopolyesters of the present invention contain substantially equal molar amounts of acid residues (100 mol%) and diol residues (100 mol%) that react at substantially the same proportions so that the total moles of repeat units are 100 mol%. Thus, the mole percentages provided in the detailed description can be based on total moles of acid residues, total moles of diol residues, or total moles of repeat units. For example, sulfopolyesters containing 30 mol% of sulfomonomers (which may be dicarboxylic acids, diols or hydroxycarboxylic acids) based on total repeating units have sulfopolyesters in total 100 mol% of repeating units It means that it contains 30 mol% of sulfomonomer. Thus, 30 moles of sulfomonomer residues are present in every 100 moles of repeat units. Similarly, a sulfopolyester containing 30 mol% of dicarboxylic acid sulfomonomers based on total acid residues means that the sulfopolyester contains 30 mol% of sulfomonomers out of 100 mol% total acid residues. Thus, in this case, 30 moles of sulfomonomer residues are present in every 100 moles of acid residues.

The sulfopolyester described herein is greater than or equal to about 0.1 dL / g when measured in a 60/40 parts by weight solution of a phenol / tetrachloroethane solvent at 25 ° C. at a concentration of about 0.5 g of sulfopolyester in 100 mL of solvent, preferably about It has an intrinsic viscosity (abbreviated herein as "Ih.V.") of greater than 0.2 to 0.3 dL / g, most preferably about 0.3 dL / g. As used herein, the term "polyester" encompasses both "homopolyester" and "copolyester" and refers to a synthetic polymer prepared by polycondensation of a bifunctional carboxylic acid and a bifunctional hydroxyl compound. The term "sulfopolyester" as used herein means any polyester, including sulfomonomers. Typically, the bifunctional carboxylic acid is a dicarboxylic acid, and the bifunctional hydroxyl compound is a dihydric alcohol such as glycols and diols. Alternatively, the bifunctional carboxylic acid can be, for example, a hydroxy carboxylic acid such as p-hydroxybenzoic acid, and the bifunctional hydroxyl compound can be an aromatic nucleus having two hydroxy substituents (eg, hydroquinone). The term "residue" as used herein means any organic structure that is incorporated into the polymer through a polycondensation reaction comprising the corresponding monomer. Thus, dicarboxylic acid residues can be derived from dicarboxylic acid monomers or related acid halides, esters, salts, anhydrides, or mixtures thereof. Accordingly, the term dicarboxylic acid, as used herein, is a dicarboxylic acid useful in the polycondensation process with diols for preparing high molecular weight polyesters, and the related acid halides, esters, semi-esters, salts, semi-salts, anhydrides , And any derivatives of dicarboxylic acids, including mixed anhydrides or mixtures thereof.

The sulfopolyesters of the present invention include one or more dicarboxylic acid residues. Depending on the type and concentration of sulfomonomer, the dicarboxylic acid residues can include from about 60 to about 100 mole percent acid residues. Other examples of concentration ranges of dicarboxylic acid residues are about 60 to about 95 mole percent, and about 70 to about 95 mole percent. Examples of dicarboxylic acids that can be used include aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, aromatic dicarboxylic acids, or mixtures of two or more of these acids. Thus, suitable dicarboxylic acids include succinic acid; Glutaric acid; Adipic acid; Azelaic acid; Sebacic acid; Fumaric acid; Maleic acid; Itaconic acid; 1,3-cyclohexanedicarboxylic acid; 1,4-cyclohexanedicarboxylic acid; Diglycolic acid; 2,5-norbornenedicarboxylic acid; Phthalic acid; Terephthalic acid; 1,4-naphthalenedicarboxylic acid; 2,5-naphthalenedicarboxylic acid; Diphenic acid; 4,4'-oxydibenzoic acid; 4,4'-sulfonyldibenzoic acid and isophthalic acid, but are not limited to these. Preferred dicarboxylic acid residues are isophthalic acid, terephthalic acid and 1,4-cyclohexanedicarboxylic acid, or dimethyl terephthalate, dimethyl isophthalate and dimethyl-1,4-cyclohexanedicarboxylate if diesters are used. And isophthalic acid and terephthalic acid residues are particularly preferred. Although dicarboxylic acid methyl ester is the most preferred embodiment, it is also acceptable to include higher alkyl esters such as ethyl, propyl, isopropyl, butyl, and the like. In addition, aromatic esters, especially phenyl, can also be used.

The sulfopolyester comprises from about 4 to about 40 mole percent, based on total repeat units, of at least one sulfomonomer residue having two functional groups attached to the aromatic or cycloaliphatic ring and one or more sulfonate groups, wherein the functional group Hydroxyl, carboxyl, or combinations thereof. Additional examples of concentration ranges of sulfomonomer residues are about 4 to about 35 mole percent, about 8 to about 30 mole percent, and about 8 to about 25 mole percent based on total repeat units. The sulfomonomer may be a dicarboxylic acid containing a sulfonate group or an ester thereof, a diol containing a sulfonate group, or a hydroxy acid containing a sulfonate group. The term "sulfonate" refers to a salt of sulfonic acid having the structure "-SO ₃ N" (where M is a cation of the sulfonate salt). The cation of the sulfonate salt may be a metal ion such as Li ⁺ , Na ⁺ , K ⁺ , Mg ⁺⁺ , Ca ⁺⁺ , Ni ⁺⁺ , Fe ⁺⁺ and the like. Alternatively, the cation of the sulfonate salt can be non-metallic, such as a nitrogen-containing base described in US Pat. No. 4,304,901. Nitrogen-based cations are derived from nitrogen-containing bases, which can be aliphatic, alicyclic or aromatic compounds. Examples of such nitrogen-containing bases include ammonia, dimethylethanolamine, diethanolamine, triethanolamine, pyridine, morpholine and piperidine. The method of the present invention for producing sulfopolyesters containing nitrogen-based sulfonate salt groups is an alkali metal salt, since monomers containing nitrogen-based sulfonate salts are typically not heat stable under the conditions required to prepare polymers in melts. It is to disperse, dissipate, or dissolve a polymer containing the required amount of sulfonate groups in the form, and then exchange alkali metal cations with nitrogen-based cations.

When a monovalent alkali metal ion is used as a cation of a sulfonate salt, the resulting sulfopolyester can be completely dispersed in water at a dispersing rate that varies depending on the content of sulfomonomer in the polymer, water temperature, surface area / thickness of the sulfopolyester, and the like. have. When divalent metal ions are used, the resulting sulfopolyester is not easily dispersed by cold water but more easily by hot water. More than one counter ion can be used in a single polymer composition, in which case it can provide a means to trim or fine-regulate the water-reactivity of the resulting article. Examples of sulfomonomer residues include sulfonate salt groups such as benzene; naphthalene; Diphenyl; Oxydiphenyl; Sulfonyldiphenyl; And aromatic acid nuclei such as methylenediphenyl, or cyclohexyl, for example; Cyclopentyl; Cyclobutyl; Cycloheptyl; And monomer residues attached to alicyclic rings such as cyclooctyl. Other examples of sulfomonomer residues that can be used in the present invention are metal sulfonate salts of sulfophthalic acid, sulfoterephthalic acid, sulfoisophthalic acid, or combinations thereof. Other examples of sulfomonomers that can be used are 5-sodiosulfoisophthalic acid and esters thereof. When the sulfomonomer residue is derived from 5-sodiosulfoisophthalic acid, typical sulfomonomer concentration ranges are from about 4 to about 35 mol%, from about 8 to about 30 mol%, and from about 8 based on the total moles of acid residues. To 25 mol%.

Sulfomonomers used in the production of sulfopolyesters are known compounds and can be prepared using methods well known in the art. For example, a sulfomonomer in which a sulfonate group is attached to an aromatic ring is sulfonated with an aromatic compound to fumed sulfuric acid to obtain the corresponding sulfonic acid and then reacted with a metal oxide or base (e.g., sodium acetate) to produce a sulfonate salt. Can be produced. Procedures for the preparation of various sulfomonomers are described, for example, in US Pat. Nos. 3,779,993, 3,018,272 and 3,528,947.

Polyesters may also be prepared using, for example, sodium sulfonate salts and ion-exchange methods where sodium is replaced by different ions (eg, zinc) when the polymer is in a dispersed form. This type of ion exchange procedure is usually superior to preparing polymers with divalent salts as sodium salts are usually more soluble in the polymer reactant melt-phase.

Sulfopolyesters include one or more diol moieties that may include aliphatic, alicyclic and aralkyl glycols. Alicyclic diols, for example 1,3- and 1,4-cyclohexanedimethanol, may exist as their pure cis or trans isomers, or as mixtures of cis and trans isomers. The term "diol" as used herein is synonymous with the term "glycol" and means any divalent alcohol. Examples of diols are ethylene glycol; Diethylene glycol; Triethylene glycol; Polyethylene glycol; 1,3-propanediol; 2,4-dimethyl-2-ethylhexane-1,3-diol; 2,2-dimethyl-1,3-propanediol; 2-ethyl-2-butyl-1,3-propanediol; 2-ethyl-2-isobutyl-1,3-propanediol; 1,3-butanediol; 1,4-butanediol; 1,5-pentanediol; 1,6-hexanediol; 2,2,4-trimethyl-1,6-hexanediol; Thiodiethanol; 1,2-cyclohexanedimethanol; 1,3-cyclohexanedimethanol; 1,4-cyclohexanedimethanol; 2,2,4,4-tetramethyl-1,3-cyclobutanediol; p-xylylenediol or a combination of one or more of these glycols.

The diol residue is a poly (ethylene glycol) residue having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) based on the total diol residue. It may contain about 100 mol%. Non-limiting examples of low molecular weight polyethylene glycols with n = 2-6 are diethylene glycol, triethylene glycol and tetraethylene glycol. Of these low molecular weight glycols, diethylene glycol and triethylene glycol are most preferred. High molecular weight polyethylene glycols of n to 7 to about 500 (abbreviated herein as "PEG") are registered as Dow Chemical Company (formerly Union Carbide) article CARBOWAX; Trademarks). Typically, PEG is used with other diols such as diethylene glycol or ethylene glycol. Based on the value of n in the range of 6 to 500, the molecular weight can be from 300 to about 22,000 g / mole. Molecular weight and mol% are inversely proportional to each other, specifically, as the molecular weight increases, the mol% decreases to obtain the defined hydrophilicity. For example, as an example of this concept, PEGs with a molecular weight of 1000 can make up to 10 mol% or less of the total diol, whereas PEGs with a molecular weight of 10,000 are typically at levels below 1 mol% of the total diol. It is considered to be incorporated.

Due to side reactions that can be controlled by changing process conditions, certain dimers, trimers and tetramer diols can be produced in situ. For example, various amounts of diethylene glycol, triethylene glycol, and tetraethylene glycol can be produced from ethylene glycol by an acid-promoted dehydration reaction that occurs easily when performing a polycondensation reaction under acidic conditions. Buffer solutions well known to those skilled in the art can be added to the reaction mixture to delay these side reactions. However, additional composition ranges are possible if the buffer is excluded and the dimerization, trimerization and tetramerization reactions proceed.

The sulfopolyester of the present invention may include 0 to about 25 mol% of branched monomer residues having three or more functional groups that are hydroxyl, carboxyl, or a combination thereof. Non-limiting examples of branched monomers include 1,1,1-trimethylol propane, 1,1,1-trimethylol ethane, glycerin, pentaerythritol, erythritol, thritol, dipentaerythritol , Sorbitol, trimellitic anhydride, pyromellitic dianhydride, dimethylol propionic acid or combinations thereof. Additional examples of branched monomer concentration ranges are 0 to about 20 mol% and 0 to about 10 mol%. Due to the presence of branched monomers, a number of possible advantages for the sulfopolyesters of the present invention can arise, including, but not limited to, the ability to trim rheology, solubility and tensile properties. For example, at constant molecular weight, branched sulfopolyesters have higher concentrations of end groups that can facilitate crosslinking reactions after polymerization than linear analogs. However, if the concentration of the branching agent is high, sulfopolyester may be liable to gel.

The sulfopolyester used in the fibers of the present invention has a glass transition temperature of 25 ° C. or higher as measured on a dry polymer using standard techniques such as differential scanning calorimetry (“DSC”), which are well known to those skilled in the art. "Abbreviated as" Tg "). The Tg of the sulfopolyester of the present invention is measured using a “dry polymer”, ie a polymer sample that removes foreign or absorbed water by heating the polymer to about 200 ° C. and returning the sample to room temperature. Typically, a first thermal injection is performed to heat the sample to a temperature above the vaporization temperature of the water, and after maintaining the sample at that temperature until the vaporization of the water absorbed by the polymer is complete (represented by a large and wide endotherm), The sample is cooled to room temperature, followed by a second thermal scan to measure Tg to dry the sulfopolyester in the DSC apparatus. Additional examples of the glass transition temperature represented by the sulfopolyester are 30 ° C or higher, 35 ° C or higher, 40 ° C or higher, 50 ° C or higher, 60 ° C or higher, 65 ° C or higher, 80 ° C or higher, and 90 ° C or higher. Other Tg is possible, but typical glass transition temperatures of the dry sulfopolyester of the present invention are about 30 ° C, about 48 ° C, about 55 ° C, about 65 ° C, about 70 ° C, about 75 ° C, about 85 ° C, and about 90 ℃.

The novel fibers of the present invention consist essentially of the sulfopolyester described above or consist of the sulfopolyester described above. However, in other embodiments, the sulfopolyesters of the present invention can be single polyesters or blended with one or more supplemental polymers to modify the properties of the resulting fibers. The supplement polymer may or may not be water dispersible depending on the application, and may or may not be miscible with the sulfopolyester. If the supplement polymer is water non-dispersible, it is preferred that the blend with the sulfopolyester is immiscible. The term “miscible” as used herein is intended to mean that the blend has a single homogeneous amorphous phase, as indicated by Tg based on a single composition. The second polymer can be “plasticized” using a first polymer that is miscible with the second polymer, for example, as illustrated in US Pat. No. 6,211,309. In contrast, as used herein, the term “immiscible” refers to a blend that exhibits two or more randomly mixed phases and exhibits more than one Tg. Some polymers are immiscible with sulfopolyesters, but are compatible. Additional comprehensive descriptions of miscible and immiscible polymer blends and various analytical techniques for determining their characteristics are described in Polymer. Blends Volumes 1 and 2, Paul and Buckle Editing, 2000, John Wiley & Sons, Inc.

Non-limiting examples of water dispersible polymers that can be blended with sulfopolyesters include polymethacrylic acid, polyvinyl pyrrolidone, polyethylene-acrylic acid copolymers, polyvinyl methyl ether, polyvinyl alcohol, polyethylene oxide, hydroxy propyl cellulose , Hydroxypropyl methyl cellulose, methyl cellulose, ethyl hydroxyethyl cellulose, isopropyl cellulose, methyl ether starch, polyacrylamide, poly (N-vinyl caprolactam), polyethyl oxazoline, poly (2-isopropyl-2 -Oxazoline), polyvinyl methyl oxazolidon, water dispersible sulfopolyester, polyvinyl methyl oxazolidinone, poly (2,4-dimethyl-6-triazinylethylene) and ethylene oxide-propylene oxide copolymer . Examples of water non-dispersible polymers that can be blended with sulfopolyesters include polyolefins such as homopolymers and copolymers of polyethylene and polypropylene; Poly (ethylene terephthalate); Poly (butylene terephthalate); Polyamides such as nylon-6; Polylactide; Caprolactone; Eastar Bio (registered trademark) (poly (tetramethylene adipate-co-terephthalate), Eastman Chemical Company product); Polycarbonate; Polyurethane; And polyvinyl chloride.

According to the present invention, it is possible to control the end-use properties of fibers or fibrous articles, such as nonwovens or nonwoven webs, produced using a blend of more than one sulfopolyester. The blend of one or more sulfopolyesters has a Tg of 25 ° C or higher for water dispersible monocomponent fibers and 57 ° C or higher for multicomponent fibers. Thus, blending can also be used to change the processing characteristics of the sulfopolyester to facilitate the production of nonwovens. In another example, an immiscible blend of polypropylene and sulfopolyester does not require true solubility and can provide a conventional nonwoven web that splits and disperses completely in water. In the case of this latter example, the desired performance is the physical properties of the polypropylene, while the sulfopolyester is only a bystander during the actual use of the article, or alternatively the sulfopolyester is removed and removed before the final form of the article is used. It is related to maintaining.

The sulfopolyester and supplemental polymers can be blended in a batch, semi-continuous or continuous process. Before melt-spinning the fibers, small batches can be easily prepared in any high intensity mixing device well known to those skilled in the art, such as a Banbury mixer. The components can also be blended into solution in a suitable solvent. The melt blending method includes blending the sulfopolyester and the supplemental polymer at a temperature sufficient to melt the polymer. The blend can be cooled and pelleted for further use, or the melt blend can be melt spun directly in fiber form from the melted blend. As used herein, the term “melting” includes, but is not limited to, simply softening the polyester. For melt mixing methods commonly known in the polymer art, see Mixing. and Compounding of Polymers (Edited by Manas-Zlozouer and Tadmer, Carl Hanser Verlag Publisher, 1994, New York, NY).

The present invention is also a water-dispersible fiber comprising a sulfopolyester having a glass transition temperature (Tg) of 25 ° C or higher, wherein the sulfopolyester is

(A) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues;

(B) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues;

(C) At least 25 mol% based on the total diol residue is poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues;

(D) 0 to about 20 mole percent of branched monomer residues having three or more functional groups, hydroxyl, carboxyl, or combinations thereof, based on total repeat units

It provides a water-dispersible fiber comprising a.

As described above, the fiber comprises a first water-dispersible polymer blended with a sulfopolyester; And optionally a water non-dispersible polymer blended with the sulfopolyester such that the blend is an immiscible blend. The fibers of the present invention contain less than 10% by weight, less than 8% by weight, or less than 6% by weight of pigment or filler, based on the total weight of the fibers. The first water-dispersible polymer is as described above. The sulfopolyester should have a glass transition temperature (Tg) of 25 ° C or higher, but for example, about 35 ° C, about 48 ° C, about 55 ° C, about 65 ° C, about 70 ° C, about 75 ° C, about 85 ° C and about 90 It may have a Tg of ℃. Sulfopolyesters may contain different concentrations of isophthalic acid residues, for example about 60 to about 95 mole percent, and about 75 to about 95 mole percent. Additional examples of isophthalic acid residue concentrations are about 70 to about 85 mole percent, about 85 to about 95 mole percent, and about 90 to about 95 mole percent. The sulfopolyester may also include from about 25 to about 95 mole percent diethylene glycol residues. Additional examples of diethylene glycol residue concentration ranges include about 50 to about 95 mole percent, about 70 to about 95 mole percent, and about 75 to about 95 mole percent. The sulfopolyester may also include ethylene glycol residues and / or 1,4-cyclohexanedimethanol (abbreviated herein as “CHDM”) residues. Typical concentration ranges for CHDM residues are about 10 to about 75 mole percent, about 25 to about 65 mole percent, and about 40 to about 60 mole percent. Typical concentration ranges for ethylene glycol moieties are about 10 to about 75 mole percent, about 25 to about 65 mole percent, and about 40 to about 60 mole percent. In other embodiments, the sulfopolyester comprises about 75 to about 96 mole percent isophthalic acid residues and about 25 to about 95 mole percent diethylene glycol residues.

The sulfopolyesters of the present invention are readily prepared from suitable dicarboxylic acids, esters, anhydrides or salts, sulfomonomers, and suitable diols or diol mixtures using typical polycondensation reaction conditions. They can be produced by continuous, semi-continuous and batch operations, and various reactor types are available. Examples of suitable reactor types include, but are not limited to, stirred tanks, continuous stirred tanks, slurries, tubular, wiping-film, falling film or extrusion reactors. The term "continuous" as used herein refers to a process in which the introduction of reactants and the recovery of products are carried out simultaneously in an uninterrupted manner. "Continuous" means that the process is substantially or completely continuous in operation, as opposed to a "batch" process. “Continuous” does not mean in any way prohibiting normal disruption to the continuity of the process, for example due to start-up, reactor maintenance or planned downtime. As used herein, the term “batch” process means a process in which all reactants are added to the reactor and then the material is not fed to or removed from the reactor during processing according to a given reaction procedure. The term "semicontinuous" means a process in which some of the reactants are added at the start of the process and the other reactants are fed continuously as the reaction proceeds. Alternatively, the semi-continuous process may also include a process similar to a batch process in which all reactants are added at the start of the process except that one or more of the products are continuously removed as the reaction proceeds. For economical reasons, the process is also advantageously continuous in order to produce an excellent color of the polymer, as the sulfopolyester may remain in the reactor at elevated temperature for too long a time (if this is allowed) and the appearance may deteriorate. It advances as an expression process.

The sulfopolyester of the present invention is prepared by procedures known to those skilled in the art. Although other processes are known and can also be used as described, for example, in U.S. Pat.Nos. 3,018,272, 3,075,952 and 3,033,822, most often sulfomonomers are added directly to the reaction mixture in which the polymer is prepared. . The reaction of the sulfomonomer, diol component and dicarboxylic acid component can be carried out using conventional polyester polymerization conditions. For example, when the sulfopolyester is prepared by an ester exchange reaction, that is, from the ester form of the dicarboxylic acid component, the reaction process may include two steps. In the first step, the diol component and a dicarboxylic acid component such as dimethyl isophthalate are elevated, typically at a pressure of about 0.0 to about 414 kPa gauge (60 pounds per square inch, “psig”) at about 150 to about 250 ° C. In the reaction for about 0.5 to about 8 hours. Preferably, the temperature of the ester exchange reaction is from about 180 to about 230 ° C. for about 1 to about 4 hours, and the preferred pressure range is from about 103 kPa gauge (15 psig) to about 276 kPa gauge (40 psig). Thereafter, the reaction product is heated under high temperature and reduced pressure to produce sulfopolyester while removing the diol, and the diol is easily vaporized under these conditions and removed from the system. When the second step or polycondensation step is determined by intrinsic viscosity at high vacuum, usually at about 230 to about 350 ° C, preferably about 250 to about 310 ° C, most preferably about 260 to about 290 ° C, the desired degree of polymerization is obtained. The polymer has a duration of about 0.1 to about 6 hours, or preferably about 0.2 to about 2 hours, until a polymer is obtained. The polycondensation step may be performed under reduced pressure from about 53 kPa (400 Torr) to about 0.013 kPa (0.1 Torr). Stirring or appropriate conditions in both steps ensure proper heat transfer and surface regeneration of the reaction mixture. Two steps of reaction are promoted by suitable catalysts, for example, alkoxy titanium compounds, alkali metal hydroxides and alcoholates, salts of organic carboxylic acids, alkyl tin compounds, metal oxides, and the like. Three-step manufacturing procedures similar to those described in US Pat. No. 5,290,631 can also be used, particularly when using mixed monomer feeds of acids and esters.

In order to ensure that the reaction of the diol component and the dicarboxylic acid component by the ester exchange reaction mechanism is completed, it is preferable to use a diol component of about 1.05 to about 2.5 mol per 1 mol of the dicarboxylic acid component. However, one skilled in the art will appreciate that the ratio of diol component to dicarboxylic acid component is usually determined by the design of the reactor in which the reaction process is performed.

In preparing sulfopolyesters by direct esterification, i.e., from the acid form of the dicarboxylic acid component, a sulfopolyester is produced by reacting a dicarboxylic acid or a mixture of dicarboxylic acids with a diol component or a mixture of diol components. Low molecular weight linear or branched sulfopolyester having an average degree of polymerization of about 1.4 to about 10 by performing the reaction at a pressure of less than about 7 kPa gauge (1 psig) to about 1379 kPa gauge (200 psig), preferably less than 689 kPa (100 psig) The product is produced. The temperature used during the direct esterification reaction is typically about 180 to about 280 ° C, more preferably about 220 to about 270 ° C. Subsequently, this low molecular weight polymer can be polymerized by a polycondensation reaction.

The water-dispersible multicomponent fibers and short-cut fibers, fibrous articles of the present invention may also contain other conventional additives and components that do not deleteriously affect their end use. For example, fillers, surface friction modifiers, light stabilizers, heat stabilizers, extrusion aids, antistatic agents, colorants, dyes, pigments, fluorescent brighteners, antibacterial agents, anti-counterfeiting markers, hydrophobicity improvers, hydrophilicity improvers, viscosity modifiers, slip Additives such as agents, tougheners, adhesion promoters, and the like.

The fibers and fibrous articles of the present invention do not require the presence of additives such as pigments, fillers, oils, waxes or fatty acid final treatment agents to prevent blocking or fusing of the fibers during processing. As used herein, the term “blocking or fusing” is understood to mean that the fibers or fiber articles are blocked together or fused together in one mass so that the fibers cannot be processed or used for their intended purpose. Blocking and fusing may occur during processing of fibers or textile articles or during storage over a period of days or weeks, which deteriorates under high temperature and high humidity conditions.

In one embodiment of the present invention, the fibers and fiber articles contain less than 10% by weight of such anti-blocking additives based on the total weight of the fibers or fiber articles. For example, fibers and fiber articles may contain less than 10% by weight of pigments or fillers. In other embodiments, the fibers and fiber articles may contain less than 9%, less than 5%, less than 3%, less than 1% and 0% by weight pigment or filler, based on the total weight of the fibers. Colorants, sometimes referred to as toners, can be added to give the sulfopolyester a desired neutral color tone and / or brightness. If colored fibers are desired, pigments or colorants can be included in the sulfopolyester reaction mixture during the reaction of the diol monomer and the dicarboxylic acid monomer, or they can be melt blended with the pre-made sulfopolyester. A preferred method of incorporating a colorant is to use a colorant having a thermally stable organic colored compound with reactive groups to improve the color tone of the sulfopolyester by copolymerizing and incorporating it into the sulfopolyester. Colorants such as dyes with reactive hydroxyl groups and / or carboxyl groups, including, but not limited to, blue and red substituted anthraquinones, can be copolymerized into the polymer chain. When dyes are used as colorants, they can be added to the copolyester reaction step after the ester exchange or direct esterification reaction.

For the purposes of the present invention, the term "fiber" refers to a high aspect ratio polymeric object that can be made of two-dimensional or three-dimensional articles, such as fabrics or non-wovens. In the context of the present invention, the term “fiber” is synonymous with “fibers” and is intended to mean one or more fibers. The fibers of the present invention may be monocomponent fibers, bicomponent fibers or multicomponent fibers. As used herein, the term "monocomponent fiber" is intended to mean a fiber prepared by melt spinning a single sulfopolyester, a blend of one or more sulfopolyesters, or a blend of one or more sulfopolyesters and one or more additional polymers, staples Fibers, single filament fibers and multifilament fibers. "Single component" is synonymous with the term "single component" and includes "biconstituent" or "multiconstituent" fibers and is a blend made from two or more polymers extruded from the same extruder. Says Monocomponent or mixed bicomponent fibers do not have a variety of polymer components arranged in separate zones located relatively constant across the cross section of the fiber, and the various polymers produce fibrils or protofibrils randomly initiated and terminated. Instead, it is usually not continuous along the entire length of the fiber. Thus, the term “single component” is not intended to exclude fibers produced from a polymer or blend of one or more polymers to which small amounts of additives may be added for coloring, antistatic properties, lubricity, hydrophilicity, and the like.

In contrast, as used herein, the term "multicomponent fiber" melts two or more fiber forming polymers in separate extruders, flows the resulting multiple polymers into one spinneret having a plurality of distribution flow paths and spins them together. It is intended to mean the fibers produced by forming the fibers of the. Multicomponent fibers are also sometimes referred to as conjugate or bicomponent fibers. The polymers are arranged in separate compartments or zones located substantially constant across the cross-section of the conjugate fiber and extend continuously along the length of the conjugate fiber. The shape of such multi-component fibers can be, for example, a sheath / core arrangement in which one polymer is surrounded by the other, or it can be a parallel arrangement, a pie arrangement or a “sea chart” arrangement. Multicomponent fibers can be prepared by separately extruding sulfopolyesters and one or more water non-dispersible polymers, for example, through spinnerets having molded or engineered transverse geometries such as “sea charts” or divided pie shapes. . Monocomponent fibers are typically staple fibers, single filament fibers or multifilament fibers having a shaped cross-section or round cross-section. Most fiber types are heat cured. Fibers can include a variety of antioxidants, pigments, and additives described herein.

Single filament fibers generally range in size from about 15 to about 8000 denier / filament (herein referred to as "d / f"). The novel fibers of the present invention typically have a d / f value of about 40 to about 5000. Single filaments may be in the form of monocomponent or multicomponent fibers. The multifilament fibers of the present invention preferably have a size of about 1.5 μm for melt blown webs, about 0.5 to about 50 d / f for staple fibers, and about 5000 d / f or less for single filament fibers. Multifilament fibers can also be used as crimped or uncrimped yarn and tow. Fibers used in melt blown webs and melt spun fabrics can be produced in microdenier sizes. The term "microdenier" as used herein is intended to mean a d / f value of 1 d / f or less. For example, the microdenier fibers of the present invention typically have d / f values of 1 or less, 0.5 or less, or 0.1 or less. Nanofibers can also be produced by electrostatic radiation.

As described above, sulfopolyesters are also advantageous for the production of bicomponent fibers and multicomponent fibers having a shaped cross section. The inventors have found that sulfopolyesters or blends of sulfopolyesters having a glass transition temperature (Tg) of 57 ° C. or higher are particularly useful for multicomponent fibers to prevent blocking and fusing of the fibers during spinning and coiling. Therefore, the present invention

(A) (i) one or more dicarboxylic acid residues; (ii) about 4 to about 40 mole percent, based on total repeating units, of at least one functional group attached to an aromatic or cycloaliphatic ring (which is hydroxyl, carboxyl, or combinations thereof) and at least one sulfonate group Sulfomonomer residues; (iii) at least 25 mole percent of the total diol residues are at least one poly (ethylene glycol) having the structure H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) Diol residues; And (iv) from 0 to about 25 mole percent, based on total repeating units, of a branched monomer residue having 3 or more functional groups, which are hydroxyl, carboxyl, or combinations thereof, at a glass transition temperature of at least 57 ° C. Water-dispersible sulfopolyester having (Tg); And

(B) a plurality of compartments comprising at least one water non-dispersible polymer immiscible with the sulfopolyester, wherein the compartments are substantially isolated from each other by a sulfopolyester intervening between the compartments.

It provides a multi-component fiber having a molded cross-section, and optionally, the fiber has a sea-island or divided pie cross-section, and contains less than 10% by weight of a pigment or filler based on the total weight of the fiber.

Dicarboxylic acids, diols, sulfopolyesters, sulfomonomers, and branched monomer residues are as described above for other embodiments of the invention. In the case of multicomponent fibers, it is advantageous for the sulfopolyester to have a Tg of 57 ° C or higher. Other examples of the glass transition temperature that the sulfopolyester or sulfopolyester blend of the multicomponent fiber of the present invention may represent are 60 ° C or higher, 65 ° C or higher, 70 ° C or higher, 75 ° C or higher, 80 ° C or higher, 85 ° C or higher, and 90 ° C or higher. Further, in order to obtain a sulfopolyester having a Tg of 57 ° C. or higher, a blend of one or more sulfopolyesters can be used in various proportions to obtain a sulfopolyester blend having the desired Tg. The Tg of the sulfopolyester blend can be calculated by using the weighted average of the Tg of the sulfopolyester component. For example, a sulfopolyester having a Tg of 48 ° C. can be blended with another sulfopolyester having a Tg of 65 ° C. in a 27:75 weight: weight ratio to provide a sulfopolyester blend having a Tg of about 61 ° C. have.

In another embodiment of the present invention, the water dispersible sulfopolyester of multicomponent fibers provides properties that allow one or more of the following:

(A) allowing multicomponent fibers to spun to the desired low denier;

(B) Of these multicomponent fibers, sulfopolyester is resistant to removal during high-pressure weaving of the web produced from the fibers, but is effectively removed at elevated temperatures after high-pressure weaving;

(C) The multi-component fiber is thermosetting, so that a stable and strong fabric is obtained.

Surprising and unexpected results have been achieved in pursuing these objectives using sulfopolyesters having specific melt viscosities and levels of sulfomonomer residues.

Thus, in this embodiment of the present invention,

(A) one or more water-dispersible sulfopolyesters; And

(B) a plurality of domains comprising one or more water non-dispersible polymers immiscible with a sulfopolyester, wherein the domains are substantially isolated from each other by a sulfopolyester intervening between the domains.

A multicomponent fiber having a molded cross-section is provided, wherein the fiber has a spin denier of less than about 6 denier / filament, and the water-dispersible sulfopolyester is measured at a strain rate of 1 radian / second at 240 ° C. When present, it exhibits a melt viscosity of less than about 12,000 poise and contains less than about 25 mole percent of one or more sulfomonomer residues based on the total moles of diacid or diol residues.

Sulfopolyesters used in these multicomponent fibers typically have a melt viscosity of less than about 12,000 poise. Preferably, the melt viscosity of the sulfopolyester is less than 10,000 poise, more preferably less than 6,000 poise, and most preferably less than 4,000 poise when measured at a strain rate of 1 radian / second at 240 ° C. In another aspect, the sulfopolyester has a melt viscosity of about 1000 to 12000 poise, more preferably 2000 to 6000 poise, and most preferably 2500 to 4000 poise, as measured at 240 ° C. and a strain rate of 1 radian / second. Indicates. Before determining the viscosity, the sample is dried in a vacuum oven at 60 ° C. for 2 days. Melt viscosity is measured on a viscometer using a 25 mm diameter parallel plate structure with 1 mm spacing. A dynamic frequency sweep is operated at a strain rate of 1 to 400 radians / second and a 10% strain width. The viscosity is then measured at 240 ° C. and a strain rate of 1 radian per second.

The level of sulfomonomer residues in the sulfopolyester polymer for use in accordance with this aspect of the invention is generally less than about 25 mol%, preferably less than 20 mol% (percent of total diacid or diol residues in the sulfopolyester. As reported). More preferably, this level is from about 4 to about 20 mole percent, even more preferably from about 5 to about 12 mole percent, and most preferably from about 7 to about 10 mole percent. The sulfomonomer for use in the present invention preferably has two functional groups and one or more sulfonate groups attached to an aromatic or cycloaliphatic ring, wherein the functional group is hydroxyl, carboxyl, or a combination thereof. Sodiosulfo-isophthalic acid monomers are particularly preferred.

In addition to the sulfomonomers already described, the sulfopolyester is preferably one or more dicarboxylic acid residues, at least 25 mole percent of total diol residues of H- (OCH ₂ -CH ₂ ) _n -OH (where n is from 2 to about At least one diol residue that is a poly (ethylene glycol) having a structure, and 0 to about 20 mole percent, based on total repeat units, of at least 3 functional groups (which are hydroxyl, carboxyl, or combinations thereof) Branched monomer residues.

In a particularly preferred embodiment, the sulfopolyester comprises from about 80 to 96 mole% dicarboxylic acid residues, from about 4 to about 20 mole% sulfomonomer residues and from 100 mole% diol residues (total 200 mole%, That is, 100 mol% diacid and 100 mol% diol are present). More specifically, the dicarboxylic acid portion of the sulfopolyester is about 60 to 80 mol% of terephthalic acid, about 0 to 30 mol% of isophthalic acid and about 4 to 20 mol% of 5-sodiosulfoisophthalic acid (5-SSIPA). Includes. The diol portion comprises about 0-50 mol% of diethylene glycol and about 50-100 mol% of ethylene glycol. Exemplary formulations according to this embodiment of the invention are described below.

The water non-dispersible component of the multicomponent fiber can include any water non-dispersible polymer described herein. Fibers can be spun according to any of the methods described herein. However, the improved rheological properties of the multicomponent fibers according to this aspect of the present invention provide improved drawing speeds. When the sulfopolyester and water non-dispersible polymer are extruded to produce a multicomponent extrudate, at least about 2000 m / min, more preferably at least about 3000 m / min, even more preferred using any of the methods disclosed herein. Multicomponent fibers can be produced by melt drawing multicomponent extrudates at speeds of at least about 4000 m / min, most preferably at least about 4500 m / min. Without wishing to be bound by any particular theory, melt drawing of the multicomponent extrudate at this rate results in at least some oriented crystallinity in the water non-dispersible component of the multicomponent fiber. This oriented crystallinity can increase the dimensional stability of nonwoven materials made from multicomponent fibers during subsequent processing.

Another advantage of multicomponent extrudates is that they can be melt drawn into multicomponent fibers with less than 6 denier / filament spun denier. Other ranges of multicomponent fiber sizes include less than 4 denier / filament, and less than 2.5 denier / filament spinning denier.

Thus, in other embodiments of the invention,

(A) one or more water-dispersible sulfopolyesters; And

(B) a plurality of domains comprising one or more water non-dispersible polymers immiscible with a sulfopolyester, wherein the domains are substantially isolated from each other by a sulfopolyester intervening between the domains.

A multi-component extrudate having a molded cross-section is provided, wherein the extrudate may be melt drawn at a rate of about 2000 m / min or more.

The multicomponent fiber comprises a plurality of compartments or domains of one or more water non-dispersible polymers that are immiscible with the sulfopolyester, wherein the compartments or domains are substantially independent of each other by a sulfopolyester intervening between the compartments or domains. It is isolated. As used herein, the term “substantially isolated” is intended to mean that the compartments or domains are separated from each other so that upon removal of the sulfopolyester, the compartments or domains may form individual fibers. For example, the compartments or domains can be in contact with each other, such as in a divided pie shape, but can be divided by impact or when the sulfopolyester is removed.

The weight ratio of sulfopolyester to water non-dispersible polymer component in the multicomponent fibers of the present invention is generally from about 60:40 to about 2:98, or from about 50:50 to about 5:95 in other examples. Typically, sulfopolyesters account for up to 50% by weight of the total weight of the multicomponent fiber.

The compartments or domains of a multicomponent fiber can include one or more water non-dispersible polymers. Examples of water non-dispersible polymers that can be used in compartments of multicomponent fibers include, but are not limited to, polyolefins, polyesters, polyamides, polylactides, polycaprolactones, polycarbonates, polyurethanes, and polyvinyl chlorides. It is not limited. For example, water non-dispersible polymers include poly (ethylene) terephthalate, poly (butylene) terephthalate, poly (cyclohexylene) cyclohexanedicarboxylate, poly (cyclohexylene) terephthalate, poly (tri Methylene) terephthalate and the like. In other examples, the water non-dispersible polymer can be biodegradable as determined by DIN Standard 54900 and / or biodegradable as determined by ASTM Standard Method D6340-98. Examples of biodegradable polyesters and polyester blends are disclosed in U.S. Patent Nos. 5,599,858, 5,580,911, 5,446,079 and 5,559,171. The term “biodegradable” as used herein with respect to the water non-dispersible polymers of the present invention means that the polymer is radioactive under the influence of an environment such as a composting environment, for example ASTM standard method D6340-98 (title “Aqueous or composting environment”. It is understood to mean that it degrades at an appropriate and clear reference period defined by the standard test method for determining aerobic biodegradation of labeled plastic materials. The water non-dispersible polymers of the present invention may also be “biodegradable”, meaning that the polymer readily degrades in a composting environment as defined by DIN standard 54900, for example. For example, biodegradable polymers initially have a reduced molecular weight in the environment by the action of heat, water, air, microorganisms and other factors. This reduction in molecular weight leads to loss of physical properties (toughness) and often fiber breakage. If the molecular weight of the polymer is sufficiently low, then the monomers and oligomers are assimilated by the microorganisms. In an aerobic environment, these monomers or oligomers are ultimately oxidized to CO ₂ , H ₂ O and new cellular biomass. In an anaerobic environment, monomers or oligomers are ultimately converted to CO ₂ , H ₂ , acetate, methane and cellular biomass.

For example, the water non-dispersible polymer can be an aliphatic-aromatic polyester (abbreviated herein as "AAPE"). The term "aliphatic-aromatic polyester" as used herein means a polyester comprising a mixture of residues from aliphatic or alicyclic dicarboxylic acids or diols and aromatic dicarboxylic acids or diols. The term "non-aromatic" as used herein with respect to the dicarboxylic acid and diol monomers of the present invention means that the carboxyl or hydroxyl groups of the monomers are not linked through an aromatic nucleus. For example, adipic acid does not contain an aromatic nucleus in its main chain, that is, a chain of carbon atoms linking carboxylic acid groups, and is therefore "non-aromatic". In contrast, the term "aromatic" means that the dicarboxylic acid or diol contains an aromatic nucleus in the main chain, for example terephthalic acid or 2,6-naphthalene dicarboxylic acid. Thus, “non-aromatic” is, for example, essentially saturated or paraffinic, unsaturated (ie, contains a non-aromatic carbon-carbon double bond), or acetylenic (ie, contains a carbon-carbon triple bond). It is intended to include both aliphatic and alicyclic structures, such as diols and dicarboxylic acids, which contain as a main chain a straight or branched or cyclic configuration of constituent carbon atoms, which may be. Accordingly, in connection with the description and claims of the present invention, non-aromatics are intended to include linear and branched chain structures (herein referred to as "aliphatic") and cyclic structures (herein referred to as "alicyclic"). do. However, the term "non-aromatic" is not intended to exclude any aromatic substituents that may be attached to the aliphatic or alicyclic diol or dicarboxylic acid. In the present invention, the bifunctional carboxylic acid is typically an aliphatic dicarboxylic acid such as, for example, adipic acid, or an aromatic dicarboxylic acid such as, for example, terephthalic acid. The bifunctional hydroxyl compound can be, for example, an alicyclic diol such as 1,4-cyclohexanedimethanol, such as a linear or branched aliphatic diol such as 1,4-butanediol, or an aromatic diol such as hydroquinone. .

AAPE is one or more substituted or unsubstituted linear or branched diols (aliphatic diols containing 2 to about 8 carbon atoms, polyalkylene ether glycols containing 2 to 8 carbon atoms and about 4 to about 12) Selected from cycloaliphatic diols containing 4 carbon atoms) linear or branched random copolyesters and / or chain extended copolyesters. Substituted diols typically include 1 to about 4 substituents independently selected from halo, C ₆ -C ₁₀ aryl and C ₁ -C ₄ alkoxy. Examples of diols that can be used are ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 1,3-butanediol , 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, polyethylene glycol, diethylene glycol, 2,2,4-trimethyl-1,6-hexanediol, Thio-diethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, triethylene glycol and tetraethylene glycol Including, but not limited to, preferred diols are 1,4-butanediol, 1,3-propanediol, ethylene glycol, 1,6-hexanediol, diethylene glycol or 1,4 -At least one diol selected from cyclohexanedimethanol. AAPE is also selected from about 35 to about 99 mole percent of aliphatic dicarboxylic acids containing 2 to about 12 carbon atoms and cycloaliphatic acids containing about 5 to about 10 carbon atoms, based on the total moles of diacid residues. Also included are discrete residues containing one or more substituted or unsubstituted linear or branched non-aromatic dicarboxylic acid residues. Substituted non-aromatic dicarboxylic acids typically contain 1 to about 4 substituents selected from halo, C ₆ -C ₁₀ aryl and C ₁ -C ₄ alkoxy. Non-limiting examples of non-aromatic diacids include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, fumaric acid, 2,2-dimethyl glutaric acid, suberic acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, diglycolic acid, itaconic acid, maleic acid and 2,5-norborneanedicarboxylic acid. In addition to the non-aromatic dicarboxylic acids, AAPE contains from about 1 to about 65 mole percent, based on the total moles of diacid residues, of one or more substituted or unsubstituted aromatic dicarboxylic acid residues containing 6 to about 10 carbon atoms. do. When substituted aromatic dicarboxylic acids are used, they typically contain 1 to about 4 substituents selected from halo, C ₆ -C ₁₀ aryl and C ₁ -C ₄ alkoxy. Non-limiting examples of aromatic dicarboxylic acids that can be used in the AAPE of the present invention are terephthalic acid, isophthalic acid, salts of 5-sulfoisophthalic acid and 2,6-naphthalenedicarboxylic acid. More preferably, the non-aromatic dicarboxylic acid comprises adipic acid, the aromatic dicarboxylic acid comprises terephthalic acid, and the diol includes 1,4-butanediol.

Other compositions possible for the AAPE of the present invention are prepared from the following diols and the following diols and dicarboxylic acids (or their polyester-forming equivalents such as diesters) based on 100 mol% of the diacid component and 100 mol% of the diol component. will be:

(1) glutaric acid (about 30 to about 75%); Terephthalic acid (about 25 to about 70%); 1,4-butanediol (about 90-100%); And modified diols (0 to about 10%);

(2) succinic acid (about 30 to about 95%); Terephthalic acid (about 5 to about 70%); 1,4-butanediol (about 90-100%); And modified diols (0 to about 10%); And

(3) adipic acid (about 30 to about 75%); Terephthalic acid (about 25 to about 70%); 1,4-butanediol (about 90-100%); And modified diols (0 to about 10%).

The modified diol is preferably selected from 1,4-cyclohexanedimethanol, triethylene glycol, polyethylene glycol and neopentyl glycol. Most preferred AAPEs are linear, branched or chain extended comprising from about 50 to about 60 mole percent adipic acid residue, from about 40 to about 50 mole percent terephthalic acid residue, and at least 95 mole percent 1,4-butanediol residue. It is a copolyester. Even more preferably, the adipic acid residues account for about 55 to about 60 mol%, the terephthalic acid residues comprise about 40 to about 45 mol%, and the diol residues are about 95 mol of 1,4-butanediol residues. %. These compositions are commercially available from Eastman Chemical Company, Kingsport, Tenn. Under the trade name Estar Bio® copolyester, and also under the trade name ECOFLEX® from BASF Corporation.

Additional specific examples of preferred AAPE include (a) 50 mol% glutaric acid residue, 50 mol% terephthalic acid residue and 100 mol% 1,4-butanediol residue, (b) 60 mol% glutaric acid residue, 40 terephthalic acid residue Poly (tetra) containing mol% and 1,4-butanediol residue 100 mol%, or (c) glutaric acid residue 40 mol%, terephthalic acid residue 60 mol% and 1,4-butanediol residue 100 mol% Methylene glutarate-co-terephthalate); (a) 85 mol% succinic acid residue, 15 mol% terephthalic acid residue and 100 mol% 1,4-butanediol residue, or (b) 70 mol% succinic acid residue, 30 mol% terephthalic acid residue and 1,4-butane Poly (tetramethylene-succinate-co-terephthalate) containing 100 mol% of diol residues; Poly (ethylene succinate-co-terephthalate) containing 70 mol% succinic acid residue, 30 mol% terephthalic acid residue and 100 mol% ethylene glycol residue; And (a) 85 mol% of adipic acid residues, 15 mol% of terephthalic acid residues and 100 mol% of 1,4-butanediol residues, or (b) 55 mol% of adipic acid residues, 45 mol% of terephthalic acid residues and 1, Poly (tetramethylene adipate-co-terephthalate) containing 100 mol% of 4-butanediol residues.

AAPE preferably comprises from about 10 to about 1,000 repeat units, preferably from about 15 to about 600 repeat units. AAPE is from about 0.4 to about 2.0 dL / g, more preferably from about 0.7 to about 2.0 ° C. when measured at 25 ° C. using a concentration of 0.5 g of copolyester in 100 ml of a 60/40 (by weight) solution of phenol / tetrachloroethane. It can have an intrinsic viscosity of about 1.6 dL / g.

AAPE can optionally contain branching agent residues. The mole percent range of the branching agent is from about 0 to about 2 mole percent, preferably about 0, based on the total moles of diacid or diol residues (depending on whether the branching agent contains a carboxyl group or a hydroxyl group). 0.1 to about 1 mol%, most preferably about 0.1 to about 0.5 mol%. The branching agent preferably has a weight average molecular weight of about 50 to about 5000, more preferably about 92 to about 3000, and a functional value of about 3 to about 6. The branching agent is, for example, an esterified residue of a polyol having 3 to 6 hydroxyl groups, a polycarboxylic acid having 3 or 4 carboxyl groups (or ester-forming equivalent groups), or a total of 3 to 6 hydroxyl groups And hydroxy acids having carboxyl groups. AAPE can also be branched by adding peroxide during reactive extrusion.

Each section of the water non-dispersible polymer can be different from each other in fineness and can be arranged in any molded or engineered cross-sectional shape known to those skilled in the art. For example, using sulfopolyesters and water non-dispersible polymers such as parallel, "sea chart", divided pies, other divisible shapes, sheaths / cores or other forms known to those skilled in the art. Bicomponent fibers with engineered geometries can be produced. Other multi-component shapes are possible. One side of the parallel, “sea” or “pie” can be subsequently removed to create very fine fibers. Methods of making bicomponent fibers are well known to those skilled in the art. In the bicomponent fiber, the sulfopolyester fiber of the present invention may be present in an amount of about 10 to about 90% by weight, and is generally used for the sheath portion of the sheath / core fiber. Other components may be, for example, poly (ethylene) terephthalate, poly (butylene) terephthalate, poly (trimethylene) terephthalate, polylactide, and the like, as well as a wide variety of other polymeric materials such as polyolefins, cellulose esters, and polyamides. Typically, when a water-insoluble or water-insoluble polymer is used, the resulting bicomponent or multicomponent fibers are not completely water dispersible. Spiral crimping can be achieved using parallel combinations with significantly different thermal shrinkage. When crimping is required, toothed or press-fit crimping is typically suitable for many applications. When the second polymer component is present in the core of the sheath / core shape, this core can be optionally stabilized.

Compared to the caustic soda-containing solution, which is sometimes required to remove other water-dispersible polymers from multicomponent fibers, the sulfopolyester is "even if it requires only neutral or weakly acidic (ie" soft "water) to disperse It is particularly useful for fibers having a "or" split pie "cross section. The term "soft water" used in this disclosure, means (the equivalent of one grain CaCO ₃ / gallon was 17.1 ppm) water has a grain / gallon of 5 or less as CaCO _3.

Another aspect of the invention

(A) (i) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues; (ii) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (iv) from 0 to about 20 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units, and having a glass transition temperature of 57 ° C. or higher ( Water dispersible sulfopolyester having Tg); And

(B) a plurality of compartments comprising at least one water non-dispersible polymer immiscible with the sulfopolyester, wherein the compartments are substantially isolated from each other by a sulfopolyester intervening between the compartments.

It is a multi-component fiber containing.

In one embodiment, the multi-component fiber has a sea-island or divided pie cross-section and contains less than 10% by weight pigment or filler based on the total weight of the fiber.

The dicarboxylic acids, diols, sulfopolyesters, sulfomonomers, branched monomer residues and water non-dispersible polymers are as previously described. In the case of the multicomponent fiber, it is advantageous for the sulfopolyester to have a Tg of 57 ° C or higher. The sulfopolyester can be a single sulfopolyester or a blend of one or more sulfopolyester polymers. Other examples of the glass transition temperature that the sulfopolyester or sulfopolyester blend may represent are 65 ° C or higher, 70 ° C or higher, 75 ° C or higher, 85 ° C or higher, and 90 ° C or higher. For example, the sulfopolyester can include about 75 to about 96 mole percent of one or more isophthalic or terephthalic acid residues and about 25 to about 95 mole percent of diethylene glycol residues. As described above, examples of water non-dispersible polymers are polyolefins, polyesters, polyamides, polylactides, polycaprolactones, polycarbonates, polyurethanes and polyvinyl chloride. In addition, water non-dispersible polymers can be biodegradable or biodegradable. For example, the water non-dispersible polymer can be an aliphatic-aromatic polyester as already described.

The novel multicomponent fibers of the present invention can be prepared by a variety of methods known to those skilled in the art. Therefore, the present invention

(A) one or more dicarboxylic acid residues;

(B) about 4 to about 40 mole percent, based on total repeating units, of at least one functional group attached to the aromatic or cycloaliphatic ring (which is hydroxyl, carboxyl, or combinations thereof) and at least one sulfonate group. Sulfomonomer residues;

(C) at least 25 mole percent of the total diol residues are at least one poly (ethylene glycol) having the structure H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) Diol residues; And

(D) 0 to about 25 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units

And a water-dispersible sulfopolyester having a glass transition temperature (Tg) of 57 ° C or higher, and

One or more water non-dispersible polymers immiscible with the sulfopolyester

A method for producing a multicomponent fiber having a molded cross-section, comprising spinning a fiber into a fiber, wherein the fiber has a plurality of compartments comprising a water non-dispersible polymer, the compartments between the compartments In one embodiment, the fibers contain less than 10% by weight of pigments or fillers, based on the total weight of the fibers. For example, small segments or fine strands in which the sulfopolyester and one or more water non-dispersible polymers are melted in separate extruders and the water non-dispersible polymer components are substantially isolated from each other by the intervention of sulfopolyesters. Multicomponent fibers can be made by flowing individual polymers into a single spinneret or extrusion die with multiple distribution flow paths to form a. The cross-section of these fibers can be, for example, a divided pie arrangement or a chart arrangement. In another example, a sulfopolyester and one or more water non-dispersible polymers are separately supplied to the spinneret's spinneret, and then the “core” in which the water non-dispersible polymer is substantially surrounded by a sulfopolyester “skin” polymer. It is extruded in the form of a sheath-core forming a. In the case of such concentric fibers, the hole supplying the "core" polymer is at the center of the spinneret outlet, and the flow conditions of the core polymer fluid are tightly controlled to maintain concentricity of the two components upon spinning. The spinneret of the spinneret can be modified so that different core and / or sheath shapes are obtained within the fiber cross section. In another example, (1) the water-dispersible sulfopolyester and the water non-dispersible polymer are separately co-extruded separately through a spinneret, and the separate polymer streams converge at substantially the same rate to combine under the surface of the spinneret. By parallel coalescing as a stream, or (2) by separately supplying the two polymer streams through spinnerets converging at substantially the same rate at the surface of the spinneret, by parallel coalescing as a combined stream at the surface of the spinneret, in parallel cross-section or Multicomponent fibers having a shape can be produced. In both cases, the speed of each polymer stream at the coalescence point is determined by its weighing pump speed, the number of spinnerets, and the size of the spinnerets.

The dicarboxylic acids, diols, sulfopolyesters, sulfomonomers, branched monomer residues and water non-dispersible polymers are as previously described. The sulfopolyester has a glass transition temperature of 57 ° C or higher. Additional examples of glass transition temperatures that can be represented by the sulfopolyester or sulfopolyester blends are 65 ° C or higher, 70 ° C or higher, 75 ° C or higher, 85 ° C or higher, and 90 ° C or higher. In one example, the sulfopolyester comprises about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues; And about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues; And 0 to about 20 mole percent, based on total repeat units, of branched monomer residues having three or more functional groups, which are hydroxyl, carboxyl, or combinations thereof. In another example, the sulfopolyester can include about 75 to about 96 mole percent of one or more isophthalic or terephthalic acid residues and about 25 to about 95 mole percent of diethylene glycol residues. As described above, examples of water non-dispersible polymers are polyolefins, polyesters, polyamides, polylactides, polycaprolactones, polycarbonates, polyurethanes and polyvinyl chloride. In addition, water non-dispersible polymers can be biodegradable or biodegradable. For example, the water non-dispersible polymer can be an aliphatic-aromatic polyester as already described. Examples of molded cross-sections include, but are not limited to, parallel, sheath-core, divided pie or ribbon (striped) structures.

In another embodiment of the invention, it has a shaped cross-section comprising spinning one or more water dispersible sulfopolyesters and one or more water non-dispersible polymers immiscible with the sulfopolyester to produce multicomponent fibers. A method of making a component fiber is provided, wherein the multicomponent fiber has a plurality of domains comprising water non-dispersible polymers, the domains being substantially isolated from each other by sulfopolyesters intervening between the domains, the The water-dispersible sulfopolyester exhibits a melt viscosity of less than about 12,000 poise when measured at a strain rate of 1 radian / second at 240 ° C., wherein the sulfopolyester is about 25 mol% based on the total moles of diacid or diol residues. Less than one sulfomonomer residue. In another embodiment, the multicomponent fiber has a spin denier of less than about 6 denier / filament.

Sulfopolyesters and water non-dispersible polymers used in these multicomponent fibers have already been discussed in this detailed description.

In another embodiment of the invention,

(A) extruding at least one water-dispersible sulfopolyester and at least one water non-dispersible polymer immiscible with the sulfopolyester to produce a multicomponent extrudate, wherein the multicomponent extrudate is -Having a plurality of domains comprising a dispersible polymer, said domains being substantially isolated from each other by said sulfopolyester intervening between said domains, and

(B) the step of melt-pulling the multi-component extrudate at a speed of about 2000 m / min or more to produce multi-component fibers

A method of manufacturing a multicomponent fiber having a molded cross-section is provided.

It is also an embodiment of the present invention that the method comprises melt drawing a multicomponent extrudate at a rate of at least about 2000 m / min, more preferably at least about 3000 m / min, and most preferably at least 4500 m / min. It is characteristic of.

Typically, upon exiting the spinneret, the fibers are quenched with an orthogonal stream of air, with the fibers solidifying. At this stage, various final treatment agents and sizing agents can be applied to the fibers. Cooled fibers are typically subsequently drawn and wound into a winding spool. Other additives, such as emulsifiers, antistatic agents, antibacterial agents, antifoaming agents, lubricants, heat stabilizers, UV stabilizers, etc., can be incorporated into the final treatment agent in effective amounts.

Optionally, the drawn fibers can be textured and wound up to produce bulky continuous filaments. This one-step technique is known in the art as spin-draw-texture. Other embodiments include flat filament (untextured) yarns or crimped or uncrimped chopped staple fibers.

By dissolving the interfacial layer or pi compartment and leaving smaller filaments or microdenier fibers of the water non-dispersible polymer (s), the sulfopolyester can be removed later. Therefore, the present invention

(A) (i) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues; (ii) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (iv) from 0 to about 20 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units, and having a glass transition temperature of 57 ° C. or higher ( Spinning a water dispersible sulfopolyester having Tg) and at least one water non-dispersible polymer immiscible with the sulfopolyester into multicomponent fibers, wherein the fibers comprise a plurality of water non-dispersible polymers Having four compartments, the compartments being substantially isolated from each other by a sulfopolyester intervening between the compartments; And

(B) generating micro-denier fibers by removing the sulfopolyester by contacting the multicomponent fibers with water.

It provides a method for producing a micro-denier fiber comprising a.

In another embodiment, the multicomponent fiber contains less than 10% by weight pigment or filler based on the total weight of the fiber.

Typically, the sulfopolyester is dissipated or dissolved by contacting the multicomponent fiber with water at about 25 to about 100 ° C, preferably about 50 to about 80 ° C for about 10 to about 600 seconds. After removing the sulfopolyester, the remaining microfibers have an average fineness of 1 d / f or less, typically 0.5 d / f or less, and more typically 0.1 d / f or less.

Typical uses of these residual water non-dispersible polymer microfibers include artificial leather, suede, wipes and filter media. Filter media made from these microfibers can be used to filter air or liquids. Filter media for liquids include, but are not limited to, water, body fluids, solvents, and hydrocarbons. Due to the ionic nature of the sulfopolyesters, the "solubility" of the saline medium, such as body fluids, is advantageously poor. This property is desirable for personal care articles and cleaning wipes that can be flushed with a waste water system or otherwise discarded. The sulfopolyester of choice was also used as a dispersant in the dyeing bath and as an anti-redeposition agent for contaminants during the washing cycle.

In another embodiment of the invention,

Spinning one or more water dispersible sulfopolyesters and one or more water non-dispersible polymers immiscible with water dispersible sulfopolyesters into multicomponent fibers, wherein the multicomponent fibers comprise the water non-dispersible polymers Multiple domains, the domains are substantially isolated from each other by the sulfopolyester intervening between the domains, and the water-dispersible sulfopolyester is about 12,000 packets when measured at a strain rate of 1 radian / second at 240 ° C. Having a melt viscosity of less than az and comprising less than about 25 mole percent of one or more sulfomonomer residues based on the total moles of diacid or diol residues;

Generating microdenier fibers by removing the water dispersible sulfopolyester by contacting the multicomponent fibers with water

Provided is a method of manufacturing microdenier fibers comprising a.

In one embodiment, the multicomponent fiber has a spin denier of less than about 6 denier / filament.

In another embodiment of the invention,

(A) extruding at least one water dispersible sulfopolyester and at least one water non-dispersible polymer that is immiscible with the water dispersible sulfopolyester to produce a multicomponent extrudate, wherein the multicomponent extrudate is Having a plurality of domains comprising a water non-dispersible polymer, the domains being substantially isolated from each other by the sulfopolyester intervening between the domains;

(B) producing a multi-component fiber by melt drawing the multi-component extrudate at a speed of about 2000 m / min or more; And

(C) preparing a microdenier fiber by removing the water-dispersible sulfopolyester by contacting the multicomponent fiber with water.

Provided is a method of manufacturing microdenier fibers comprising a.

The multicomponent extrudate may be melt drawn at a rate of at least about 2000 m / min, more preferably at least about 3000 m / min, and most preferably at least 4500 m / min.

Such sulfomonomers and sulfopolyesters suitable for use according to the invention are described above.

In one embodiment, the water used to remove sulfopolyester from multicomponent fibers is at a temperature above room temperature. In other embodiments, the water used to remove the sulfopolyester is at least about 45 ° C, at least about 60 ° C, or at least about 80 ° C.

In another embodiment of the present invention, another method for producing a cut water non-dispersible polymer microfiber is provided. The above method

(A) cutting the multicomponent fiber into cut multicomponent fibers;

(B) contacting the fiber-containing feedstock comprising the cut multicomponent fibers with water to produce a fiber mixing slurry;

(C) heating the fiber mixing slurry to produce a heated fiber mixing slurry;

(D) optionally, mixing the fiber mixing slurry in a shear zone;

(E) removing at least a portion of the sulfopolyester from the cut multicomponent fiber to produce a slurry mixture comprising the sulfopolyester dispersion and water non-dispersible polymer microfibers; And

(F) separating the cut water non-dispersible polymer microfibers from the slurry mixture.

It includes.

The multicomponent fiber can be cut to any length that can be used to make a nonwoven article. In one embodiment of the invention, the multicomponent fiber can be cut to a length ranging from about 1 mm to about 50 mm. In other embodiments, the multicomponent fiber is about 1 mm to about 25 mm, about 1 mm to about 20 mm, about 1 mm to about 15 mm, about 1 mm to about 10 mm, about 1 mm to about 6 mm, It can be cut to lengths ranging from about 1 mm to about 5 mm, from about 1 mm to about 5 mm. In another embodiment, the cut multicomponent fibers are cut to a length of less than about 25 mm, less than about 20 mm, less than about 15 mm, less than about 10 mm, or less than about 5 mm. In another aspect of the invention, the multicomponent fibers can be cut into mixtures of various lengths.

The term "staple fiber" as used in the present disclosure is used to define fibers cut to lengths of greater than 25 mm to about 50 mm. The term "short-cut fiber" is used to define fibers cut to a length of about 25 mm or less.

The fiber-containing feedstock can include any other type of fiber useful for the manufacture of nonwoven articles. In one embodiment, the fiber-containing feedstock further comprises one or more fibers selected from the group consisting of cellulose fiber pulp, glass fiber, polyester fiber, nylon fiber, polyolefin fiber, rayon fiber, and cellulose ester fiber. can do.

The fiber-containing feedstock is mixed with water to produce a fiber mixing slurry. Preferably, in order to facilitate removal of the water-dispersible sulfopolyester, the water used may be soft water or deionized water. Training is defined above in the present disclosure. In one embodiment of the present invention, one or more water softeners can be used to facilitate removal of the water dispersible sulfopolyester from multicomponent fibers. Any water softener known in the art can be used. In one embodiment, the water softening agent is a chelating agent or calcium ion blocker. Applicable chelating agents or calcium ion blockers are compounds that contain a plurality of carboxylic acid groups per molecule, but the carboxylic acid groups are separated by 2 to 6 atoms in the molecular structure of the chelating agent. Tetrasodium ethylene diamine tetraacetic acid (EDTA) is an example of the most common chelating agent, which contains four carboxylic acid groups per molecular structure, separated by three atoms between adjacent carboxylic acid groups. The sodium polyacrylate salt is an example of a calcium sequestrant containing a carboxylic acid group separated by two atoms between the carboxylic acid groups. The sodium salt of maleic acid or succinic acid is an example of the most basic chelating agent compound. A further example of an applicable chelating agent is to have a plurality of carboxylic acid groups per molecular structure, but the carboxylic acid groups are separated by the required distance (2 to 6 atomic units), so that divalent or polyvalent cations (e.g. calcium) and Compounds, which cause a preferred steric interaction of the chelating agent, are preferentially bound to divalent or polyvalent cations. Such compounds include, for example, diethylenetriaminepentaacetic acid; Diethylenetriamine-N, N, N ', N', N "-pentaacetic acid; pentanoic acid; N, N-bis (2- (bis- (carboxymethyl) amino) ethyl) -glycine; diethylenetriamine Pentaacetic acid; [[(carboxymethyl) imino] bis (ethylenenitrilo)]-tetra-acetic acid; edetic acid; ethylenedinitrotetraacetic acid; EDTA, free base; EDTA, free acid; ethylenediamine-N, N, N ', N'-tetraacetic acid; hampen; versene; N, N'-1,2-ethane diylbis- (N- (carboxymethyl) glycine); ethylenediamine tetra-acetic acid; N, N -Bis (carboxymethyl) glycine; triglycolamic acid; trilon A; α, α ', α "-trimethylaminetricarboxylic acid; Tri (carboxymethyl) amine; Aminotriacetic acid; Hampshire NTA acid; Nitrilo-2,2 ', 2 "-triacetic acid; teatriplex i; nitrilotriacetic acid; and mixtures thereof.

The required amount of water softener depends on the hardness of the water used in terms of Ca ⁺⁺ and other polyvalent ions.

The fiber mixture slurry is heated to produce a heated fiber mixture slurry. The temperature is a temperature sufficient to remove a portion of the sulfopolyester from the multicomponent fiber. In one embodiment of the invention, the fiber mixing slurry is heated to a temperature in the range of about 50 to about 100 ° C. Other temperature ranges are in the range of about 70 to about 100 ° C, in the range of about 80 to about 100 ° C, and in the range of about 90 to about 100 ° C.

Optionally, the fiber mixing slurry is mixed in a shear zone. The degree of mixing is sufficient to isolate and remove the water dispersible sulfopolyester from the multicomponent fibers and separate the water non-dispersible polymer microfibers. In one embodiment of the invention, 90% of the sulfopolyester is removed. In another embodiment 95% of the sulfopolyester is removed, and in another embodiment more than 98% of the sulfopolyester is removed. The shear zone may include any type of equipment capable of providing the shearing action needed to isolate and remove water dispersible sulfopolyesters from multicomponent fibers and separate water non-dispersible polymer microfibers. Examples of such equipment include, but are not limited to, pulpers and refiners.

After contact and heating with water, the water-dispersible sulfopolyester in the multicomponent fiber is isolated and separated from the water non-dispersible polymer microfiber, resulting in a slurry mixture comprising the sulfopolyester dispersion and the water non-dispersible polymer microfiber. Produces The cut water non-dispersible polymer microfibers can then be separated from the sulfopolyester dispersion by any means known in the art. For example, the slurry mixture can be passed through separation equipment, such as screens and filters. Optionally, the water non-dispersible polymer microfibers can be washed once or multiple times to remove larger amounts of water dispersible sulfopolyester.

Removal of the water-dispersible sulfopolyester can be determined by physical observation of the slurry mixture. Water The water used to clean the non-dispersible polymer microfibers is transparent if the water-dispersible sulfopolyester is mainly removed. Also, if the water dispersible sulfopolyester is still removed, the water used to clean the water non-dispersible polymer microfibers may be milky. In addition, if the water-dispersible sulfopolyester remains on the water non-dispersible polymer microfibers, the microfibers can be somewhat tacky and adhesive.

The water-dispersible sulfopolyester can be recovered from the sulfopolyester dispersion by any method known in the art.

In another embodiment of the invention, there is provided a water non-dispersible polymer microfiber comprising one or more water non-dispersible polymers, wherein the water non-dispersible polymer microfibers have an equivalent diameter of less than 5 microns. (equivalent diameter) and a length of less than 25 mm. The water non-dispersible polymer microfibers are prepared by the microfiber manufacturing method described above. In another aspect of the invention, the water non-dispersible polymer microfibers have an equivalent diameter of less than 3 microns and a length of less than 25 mm. In another embodiment of the invention, the water non-dispersible polymer microfibers have an equivalent diameter of less than 5 microns or less than 3 microns. In other embodiments of the invention, the water non-dispersible polymer microfibers have a length of less than 21 mm, less than 10 mm, less than 6.5 mm, and less than 3.5 mm. Once separated, the domains or compartments in the multicomponent fiber produce a number of non-dispersible polymer microfibers.

The present invention also includes fibrous articles comprising the water dispersible fibers, multicomponent fibers, microdenier fibers or water non-dispersible polymer microfibers described above. The term "fiber article" is understood to mean any article having fibers or similar to fibers. Non-limiting examples of textile articles include multicomponent fibers, yarns, cords, tapes, fabrics, melt blown webs, spin bonded webs, heat bonded webs, high pressure woven webs, nonwoven webs and nonwovens, and combinations thereof; Items including one or more layers of fibers such as multi-layer nonwovens, laminates and composites from these fibers, gauze, bandages, diapers, training pants, tampons, surgical gowns and masks, sanitary napkins, and the like. In addition, textile articles can include alternative inserts for a variety of personal hygiene and cleaning articles. The fibrous articles of the present invention can be bonded, laminated, attached to or used with other materials that may or may not be water dispersible. A fibrous article, such as a nonwoven layer, can be bonded to a flexible plastic film or backing of a water non-dispersible material (eg, polyethylene). For example, such an assembly can be used as a component of a disposable diaper. Fiber articles can also be produced by overblowing fibers onto other substrates, creating a very colorful combination of engineered melt blown, spin bonded film or membrane structures.

The textile articles of the present invention include nonwovens and nonwoven webs. Nonwovens are defined as fabrics made directly from a fiber web without weaving or knitting operations. The Textile Institute defines a nonwoven as a textile structure made directly from fibers rather than yarn. The fabric is usually reinforced by a variety of techniques including, but not limited to, adhesive bonding, mechanical interlocking by needling or fluid jet entanglement, thermal bonding and stitch bonding, thereby strengthening gum web or batt. Or from continuous filaments. For example, the multicomponent fibers of the present invention can be formed into a fabric by any known fabric forming process. The resulting fabric or web can be converted to a microdenier fiber web by applying sufficient force to split the multicomponent fibers, or by contacting the web with water to remove sulfopolyester and leaving the remaining microdenier fibers. .

In another embodiment of the invention,

(A) (i) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues based on total acid residues; (ii) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues; (iii) 25% by mole or more based on total diol residues are poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer from 2 to about 500) One or more diol residues; And (iv) from 0 to about 20 mole percent of branched monomer residues having 3 or more functional groups (which are hydroxyl, carboxyl, or combinations thereof), based on total repeat units, and having a glass transition temperature of 57 ° C. or higher ( Spinning the water dispersible sulfopolyester having Tg) and at least one water non-dispersible polymer that is immiscible with the sulfopolyester into a multicomponent fiber, wherein the multicomponent fiber comprises a water non-dispersible polymer. Having a plurality of compartments, the compartments being substantially isolated from each other by a sulfopolyester intervening between the compartments;

(B) collecting the multicomponent fibers of step (A) by overlapping to produce a nonwoven web; And

(C) generating a microdenier fiber web by removing the sulfopolyester by contacting the nonwoven web with water.

It provides a method for producing a micro-denier fiber web comprising a.

In another embodiment of the present invention, the multicomponent fibers used contain less than 10% by weight pigment or filler based on the total weight of the fibers.

In another embodiment of the invention,

(A) spinning at least one water-dispersible sulfopolyester and at least one water non-dispersible polymer that is immiscible with the sulfopolyester, into a multicomponent fiber, wherein the multicomponent fiber is a water non-dispersible polymer. Having a plurality of domains comprising, the domains are substantially isolated from each other by the sulfopolyester intervening between the domains, and the water-dispersible sulfopolyester is measured at a strain rate of 1 radian / second at 240 ° C. When it exhibits a melt viscosity of less than about 12,000 poise and comprises less than about 25 mole percent of one or more sulfomonomer residues based on the total moles of diacid or diol residues;

(B) collecting the multicomponent fibers of step (A) to produce a nonwoven web; And

(C) generating a microdenier fiber web by removing the sulfopolyester by contacting the nonwoven web with water.

A method of manufacturing a microdenier fiber web comprising a.

In another embodiment of the invention, the multicomponent fiber used has a spin denier of less than about 6 denier / filament.

In another embodiment of the invention,

(A) extruding at least one water dispersible sulfopolyester and at least one water non-dispersible polymer that is immiscible with the water dispersible sulfopolyester to produce a multicomponent extrudate, wherein the multicomponent extrudate is Having a plurality of domains comprising a water non-dispersible polymer, the domains being substantially isolated from each other by the water dispersible sulfopolyester intervening between the domains;

(B) producing a multi-component fiber by melt drawing the multi-component extrudate at a speed of about 2000 m / min or more;

(C) collecting the multicomponent fibers of step (B) to produce a nonwoven web; And

(D) generating a microdenier fiber web by removing the sulfopolyester by contacting the nonwoven web with water.

A method of manufacturing a microdenier fiber web comprising a.

The method also preferably comprises the step of high pressure weaving the multicomponent fibers of the nonwoven web before step (C). In one embodiment of the present invention, the high pressure weaving step results in a loss of less than about 20%, less than 15% or less than 10% by weight of the sulfopolyester contained in the multicomponent fiber. In pursuing the goal of reducing the loss of sulfopolyester during high water pressure weaving, the water used during this process is preferably less than about 45 ° C, more preferably less than about 35 ° C, most preferably less than about 30 ° C Has a temperature of In one embodiment of the present invention, it is desirable that the water used during high pressure weaving is as close to room temperature as possible to minimize the loss of sulfopolyester from multicomponent fibers. Conversely, removal of the sulfopolyester polymer during step (C) can be preferably carried out using water having a temperature of at least about 45 ° C, more preferably at least about 60 ° C, most preferably at least about 80 ° C.

Prior to step (C) after high-pressure weaving, a thermal curing step comprising heating the nonwoven web to at least about 100 ° C, more preferably at least about 120 ° C, can be performed on the nonwoven web. The thermal curing step helps to relieve internal fiber stress and create dimensional stability fabric products. When the heat curable material is reheated to a heated temperature during the heat curing step, it is preferred that it exhibits a surface area shrinkage of less than about 5% of its original surface area. More preferably, the shrinkage is less than about 2% of the original surface area, and most preferably, the shrinkage is less than about 1%.

The sulfopolyester used in multicomponent fibers can be any of those described herein. In one embodiment, the sulfopolyester has a melt viscosity of less than about 6000 poise when measured at a strain rate of 1 radian / second at 240 ° C. and has less than about 12 moles of one or more sulfomonomer residues based on total repeat units. Includes. Sulfopolyesters of these types have already been described herein.

In addition, the method of the present invention is preferably multi-component fibers at a fiber speed of at least 2000 m / min, more preferably at least about 3000 m / min, even more preferably at least about 4000 m / min, and most preferably at least about 5000 m / min. It includes the step of drawing.

In another embodiment of the present invention, a non-woven article comprising water non-dispersible polymer microfibers can be prepared. Non-woven articles comprising water non-dispersible polymer microfibers are produced by a method selected from the group consisting of a dry-laid process and a wet-laid process. Methods and multicomponent fibers for making water non-dispersible polymer microfibers are described herein above.

In one embodiment of the present invention, at least 1% water non-dispersible polymer microfibers are contained in the nonwoven article. Other amounts of water non-dispersible polymer microfibers contained in the nonwoven article are at least 10%, at least 25% and at least 50%.

In another aspect of the invention, the nonwoven article may further include one or more other fibers. The other fibers may be any known in the art depending on the type of nonwoven article to be manufactured. In one embodiment of the present invention, the other fibers may be selected from the group consisting of cellulose fiber pulp, glass fiber, polyester fiber, nylon fiber, polyolefin fiber, rayon fiber, cellulose ester fiber and mixtures thereof. .

The nonwoven article may further include one or more additives. Additives include, but are not limited to starch, fillers and binders. Other additives are mentioned in other sections herein.

In general, methods of making this nonwoven article from water non-dispersible microfibers made from multicomponent fibers can be divided into the following groups: dry-laminated webs, wet-laminated webs, and combinations between these processes, or Combination of these processes with other non-woven processes.

Generally, dry-laminated nonwoven articles are made with staple fiber processing equipment designed to handle fibers in a dry state. This includes mechanical processes, for example carding, aerodynamics, and other air-laminated pathways. In addition, this category includes non-woven articles made of tow-shaped filaments, fabrics made of staple fibers, and stitching filaments or yards (ie stitch-bonded non-woven fabrics). Carding is a process of disentangling, washing, and intermixing of fibers to produce a web for further processing into nonwoven articles. This process mainly aligns fibers that are fixed to each other as a web by mechanical entangling and fiber-fiber friction. Cards (eg, rolled cards) are generally constructed from one or more main cylinders, rollers, or stationary tops, one or more doffers, or various combinations of these major components. A carding operation is a combination or operation of a number of non-dispersible microfibers between locations of cards on a series of interoperable card rollers. Types of cards include roller cards, wool cards, cotton cards and random cards. Garnets can also be used to align these fibers.

Multicomponent fibers cut in a dry-laid process may be water non-dispersible polymer microfibers may also be aligned by air-lamination. These fibers are sent by air current to a collector, which can be a flat conveyor or drum.

Extruded-molded webs can also be produced from the multicomponent fibers of the present invention. Examples include spin-bonded and melt-blown. Extrusion techniques are used to produce spin-bonded, melt-blown and porous-film nonwoven articles. This nonwoven article is made by machines associated with polymer extrusion methods such as melt-spinning, film casting and extrusion coating. The nonwoven article is then contacted with water to remove the water dispersible sulfopolyester, resulting in a nonwoven article comprising water non-dispersible polymer microfibers.

In the spin-bonding process, water-dispersible sulfopolyesters and water non-dispersible polymers are extruded by extruding multicomponent filaments, orienting them as a bundle or grouping, laminating them on a transport screen and interlocking them. Directly converted to fabric. The interlocking may be performed by thermal fusion, mechanical entangling, high pressure weaving, chemical binder or a combination of these processes.

Molten blown fabrics are also made directly from water dispersible sulfopolyesters and water non-dispersible polymers. The polymer is melted and extruded. When the melt passes through the extrusion orifice, it is blown into the air at high temperature. The air stream dilutes and solidifies the molten polymer. The multicomponent fiber can then be separated from the air stream as a web and compressed between heated rolls.

Combined spin-bonding and melt-bonding processes can also be used to make nonwoven articles.

The wet lamination process involves the use of papermaking techniques to produce nonwoven articles. Such nonwoven articles are made by pumping slurry (eg, hammer mills) associated with pulp fibrillation and a continuous screen designed to handle paper, for example, short fibers in a fluid.

In one embodiment of the wet lamination process, water non-dispersible polymer microfibers are suspended in water, transferred from the forming screen to a forming unit where water is drained, and the fibers are placed on the screen wire.

In another embodiment of the wet lamination process, the water non-dispersible polymer microfibers are initially 1,500 meters / minute in the hydraulic press in a dewatering module (e.g., suction box, foil, and curature). It is dehydrated on a wire mesh or sheave rotating at high speed. The sheet is dehydrated to a solids content of about 20 to 30%. The sheet can then be pressed and dried.

In another embodiment of the wet-laid process,

(A) optionally, washing the water non-dispersible polymer microfiber comprising the water non-dispersible synthetic polymer with water;

(B) adding water to the water non-dispersible polymer microfiber to form a water non-dispersible polymer microfiber slurry;

(C) optionally, adding other fibers and / or additives to the water non-dispersible polymer microfiber slurry; And

(D) moving the water non-dispersible polymer microfiber slurry into a wet-laid nonwoven zone to produce a nonwoven article.

A process comprising a is provided.

In step (A), the number of washes depends on the specific application selected for the water non-dispersible polymer microfiber. In step (B), sufficient water is added to the ribbon fibers to allow them to migrate to the wet-laid nonwoven zone.

Wet-laid nonwoven zones include any device known in the art that can produce wet-laid nonwoven articles. In one embodiment of the present invention, the wet-laid nonwoven zone comprises one or more screens, meshes, or sieves to remove water from a water non-dispersible polymer microfiber slurry.

In another embodiment of the wet-laid process,

(A) The water-dispersible polymer microfiber and water non-dispersible polymer microfiber slurry containing the water-dispersible sulfopolyester are removed by contacting the cut multicomponent fiber with water to remove a part of the water-dispersible sulfopolyester. Generating;

(B) optionally, washing the water non-dispersible polymer microfibers with water;

(C) optionally, adding other fibers and / or additives to the water-dispersible polymer slurry; And

(D) transferring the water non-dispersible polymer microfiber containing slurry to a wet-laid nonwoven zone to produce a nonwoven article.

A process comprising a is provided.

In another embodiment of the invention, the water non-dispersible microfiber slurry is mixed before moving into the wet-laid nonwoven zone.

Web-bonding processes may also be used in the manufacture of nonwoven articles. This process can be divided into chemical process and physical process. Chemical bonding refers to bonding fibers and / or fiber webs together using water-based and solvent-based polymers. The binder can be applied by saturation, impregnation, spraying, printing or application as a foam. Physical bonding processes include thermal processes such as calendering and hot-air bonding, and mechanical processes such as needling and high pressure weaving. The needling or needle-punching process interlocks the fibers by physically moving some of the fibers from an almost horizontal position to an almost vertical position. Needle-punching may be performed by a needleloom. The needle room generally includes a web-feeding machine portion, a needle beam including a needleboard holding the needle, a striper plate, a bed plate and a fabric winding machine portion.

Stitch-bonding is a mechanical bonding method that interlocks a fibrous web with or without a yarn using a knitted element. Examples of stitch-bonding machines include, but are not limited to, Maliwatt, Arachne, Maliblies, and Arabeva.

Non-woven articles include: 1) mechanical fiber binding and interlocking to a web or mat; 2) various techniques for fusing fibers, including the use of binder fibers that utilize the thermoplastic properties of certain polymers and polymer blends; 3) use of starch, casein, cellulose derivatives, or binding resins such as acrylic latex or synthetic resins such as urethane; 4) powder adhesive binders; Or 5) a combination thereof. Fibers are often deposited in a random manner, but orientation in one direction is possible and is subsequently combined using one of the methods described above.

The fibrous articles of the present invention may also include one or more layers of water dispersible fibers, multicomponent fibers, or microdenier fibers. The fibrous layer can be one or more nonwoven layers, loosely coupled superimposed fibers, or a combination thereof. In addition, textile articles may include child care articles, such as infant diapers; Children's bowel movement pants; Adult care items, such as adult diapers and adult incontinence pads; Feminine care articles, such as feminine sanitary napkins, panty liners, and tampons; wife; Fiber-containing cleaning articles; Medical and surgical care items such as medical wipes, tissues, gauze, examination bed covers, surgical masks, gowns, bandages, and wound dressings; textile; Personal care and health care articles, including but not limited to, elastomeric yarns, wipes, tapes, other protective barriers, and packaging materials. Fiber articles can be used to absorb liquids or can be pre-wet with various liquid compositions and used to impart the composition to a surface. Non-limiting examples of liquid compositions include wetting agents; detergent; Skin care articles such as cosmetics, ointments, pharmaceuticals, emollients, and fragrances. Fiber articles may also include various powders and particulates to improve absorbency or as a delivery vehicle. Examples of powders and particulates include, but are not limited to, talc, starch, various water absorbent, water dispersible, or water swellable polymers such as superabsorbent polymers, sulfopolyesters, and poly (vinyl alcohol), silica, pigments, and microcapsules. Does not work. In addition, additives may be present depending on the needs for the particular application, but are not required. Examples of additives include oxidation stabilizers, UV absorbers, colorants, pigments, opacifying agents (delustrants), light brighteners, fillers, nucleating agents, plasticizers, viscosity modifiers, surface modifiers, antibacterial agents, fungicides, low temperature fluidity inhibitors, branching agents, And catalysts.

In addition to being water dispersible, the textile articles described above may be washable. The term "washable" as used herein means that it can be discarded in a conventional toilet and introduced into a local sewage or residential purification system without causing obstruction or blockage in the toilet or sewage system.

The fibrous article may also include a water-dispersible film comprising a second water-dispersible polymer. The second water-dispersible polymer may be the same or different from the above-described water-dispersible polymer used in the fibers and fiber articles of the present invention. Thus, in one embodiment, for example, the second water-dispersible polymer can be an additional sulfopolyester comprising (A) to (D):

(A) about 50 to about 96 mole percent of one or more isophthalic acid or terephthalic acid residues, based on total acid residues;

(B) about 4 to about 30 mole percent sodiosulfoisophthalic acid residues based on total acid residues;

(C) A die wherein at least 15 mol% based on the total diol residue is a poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer ranging from 2 to about 500) At least one residue;

(D) 0 to about 20 mole percent of branched monomer residues having at least 3 functional groups, hydroxyl, carboxyl, or combinations thereof, based on total repeat units.

The additional sulfopolyester can be blended with one or more of the auxiliary polymers described above to modify the properties of the resulting textile article. The auxiliary polymer may or may not be water-dispersible depending on the application. The auxiliary polymer may be miscible or miscible with the additional sulfopolyester.

Additional sulfopolyesters may contain isophthalic acid residues at different concentrations, for example from about 60 to about 95 mole percent, and from about 75 to about 95 mole percent. Additional examples of isophthalic acid residue concentration ranges are about 70 to about 85 mole percent, about 85 to about 95 mole percent, and about 90 to about 95 mole percent. Additional sulfopolyesters may also include from about 25 to about 95 mole percent diethylene glycol residues. Additional examples of diethylene glycol residue concentration ranges include about 50 to about 95 mole percent, about 70 to about 95 mole percent, and about 75 to about 95 mole percent. Additional sulfopolyesters may also include ethylene glycol and / or 1,4-cyclohexanedimethanol residues. Typical concentration ranges for CHDM residues are about 10 to about 75 mole percent, about 25 to about 65 mole percent, and about 40 to about 60 mole percent. Typical concentration ranges for ethylene glycol residues are about 10 to about 75 mole percent, about 25 to about 65 mole percent, and about 40 to about 60 mole percent. In another embodiment, the additional sulfopolyester comprises from about 75 to about 96 mole percent isophthalic acid residues and from about 25 to about 95 mole percent diethylene glycol residues.

According to the present invention, the sulfopolyester film component of the textile article can be prepared as a single layer or multilayer film. Single-layer films can be produced by conventional casting techniques. The multilayer film can be produced by a conventional lamination method or the like. The film may be of normal thickness, but the overall thickness is usually about 2 to about 50 mils.

The film-containing fibrous article can include one or more layers of water-dispersible fibers as described above. The fibrous layer may be one or more nonwoven layers, a layer of loosely coupled superimposed fibers, or a combination thereof. In addition, film-containing fiber articles can include personal and health care articles as described herein above.

As noted above, fiber articles can also include a variety of powders and particulates to improve absorbency or as a delivery vehicle. Therefore, in one embodiment, the fibrous article of the present invention comprises a powder comprising a third water-dispersible polymer, which may be the same or different from the water-dispersible polymer component described above. Other examples of powders and particulates include talc, starch, various water absorbent, water dispersible, or water swellable polymers such as poly (acrylonitrile), sulfopolyesters, and poly (vinyl alcohol), silica, pigments, and microcapsules. Including but not limited to.

The novel fibers and textile articles of the present invention have many possible uses in addition to the above-mentioned uses. One novel application involves melt blowing a film or nonwoven into a flat, curved, or molded surface to provide a protective layer. This layer provides surface protection to durable equipment during shipment. At the destination, before using the equipment, the outer layer of sulfopolyester can be washed away. Additional embodiments of this general use concept may include personal care articles that provide a temporary barrier layer for some reusable or limited use garments or covers. For military use, activated carbon and chemical absorbents can be sprayed just before the collector onto a tapered filament pattern so that the melt blown matrix adheres to the entire exposed surface. The chemisorbent can even be changed by melt blowing on another layer in the anterior operating region when a threat arises.

The main advantage inherent in sulfopolyesters is the ease of removing or recovering the polymer from the aqueous dispersion via flocculation or precipitation by the addition of ionic moieties (such as salts). Other methods may also be used, such as pH adjustment, non-solvent addition, freezing, and the like. Thus, textile articles, such as outer abrasion protection garments, can potentially be safely handled in much less volume for acceptable procedures such as incineration, even if the polymer becomes a hazardous waste after successful use of the protective barrier.

Insoluble or dried sulfopolyesters include fluff pulp, cotton, acrylic, rayon, lyocell, PLA (polylactide), cellulose acetate, cellulose acetate propionate, poly (ethylene) Terephthalate, poly (butylene) terephthalate, poly (trimethylene) terephthalate, poly (cyclohexylene) terephthalate, copolyester, polyamide (nylon), stainless steel, aluminum, treated polyolefin, PAN (poly Acrylonitrile), and polycarbonate, and is known to form strong adhesive bonds with a wide range of substrates. Therefore, the nonwoven fabric of the present invention can be used as a laminating adhesive or binder that can be bonded by known techniques such as heat, radio wave (RF), microwave, and ultrasonic methods. The application of sulfopolyesters to enable RF activation has been disclosed in a number of recent patents. Therefore, the novel nonwoven fabric of the present invention may have bifunctional or even multifunctionality in addition to adhesive use. For example, the nonwoven fabric of the present invention can obtain disposable baby diapers that act as water-reactive adhesives as well as fluid care components of the final assembly.

In addition, the present invention,

(A) (i) one or more dicarboxylic acid residues;

(ii) from about 4 to about 40 mole percent, based on total repeating units, of a sulfomonomer residue having at least one metal sulfonate group attached to an aromatic or cycloaliphatic ring and two functional groups that are hydroxyl, carboxyl, or a combination thereof. One or more;

(iii) 20% by mole or more based on total diol residue is a die of poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer ranging from 2 to about 500) At least one residue; And

(iv) 0 to about 25 mole% of branched monomer residues having at least 3 functional groups, hydroxyl, carboxyl, or combinations thereof, based on total repeat units

And heating the water-dispersible polymer composition containing less than 10% by weight of pigment or filler based on the total weight of the polymer composition to a temperature above its pour point; And

(B) the step of melt spinning the filament

It provides a method for producing water-dispersible fibers comprising a. As described herein above, the water-dispersible polymer can optionally be blended with sulfopolyester. In addition, water non-dispersible polymers can optionally be blended with sulfopolyesters to form blends that are immiscible blends. As used herein, the term “flow point” refers to the temperature at which the viscosity of the polymer composition allows extrusion or other forms of processing through a spinneret or extrusion die. Dicarboxylic acid residues can include from about 60 to about 100 mole percent acid residues, depending on the type and concentration of sulfomonomer. Other examples of concentration ranges of dicarboxylic acid residues are from about 60 mol% to about 95 mol% and from about 70 mol% to about 95 mol%. Preferred dicarboxylic acid residues are isophthalic acid, terephthalic acid, and 1,4-cyclohexanedicarboxylic acid, or dimethyl terephthalate, dimethyl isophthalate, and dimethyl-1,4-cyclohexanedicarboxyl if diesters are used. Rate, isophthalic acid and terephthalic acid residues are particularly preferred.

The sulfomonomer may be a dicarboxylic acid containing a sulfonate group or an ester thereof, a diol containing a sulfonate group, or a hydroxy acid containing a sulfonate group. Additional examples of concentration ranges of sulfomonomer residues are about 4 to about 25 mole percent, about 4 to about 20 mole percent, about 4 to about 15 mole percent, and about 4 to about 10 mole percent, based on total repeat units. The cation of the sulfonate salt may be a metal ion such as Li ⁺ , Na ⁺ , K ⁺ , Mg ⁺⁺ , Ca ⁺⁺ , Ni ⁺⁺ , Fe ^++, and the like. Alternatively, the cation of the sulfonate salt can be non-metallic, such as a nitrogenous base as described above. Examples of sulfomonomer residues that can be used in the method of the present invention are sulfophthalic acid, sulfoterephthalic acid, metal sulfonate salts of sulfoisophthalic acid, or combinations thereof. Another example of a sulfomonomer that can be used is 5-sodiosulfoisophthalic acid or an ester thereof. When sulfomonomer residues are derived from 5-sodiosulfoisophthalic acid, typical sulfomonomer concentration ranges are from about 4 to about 35 mol%, from about 8 to about 30 mol%, and from about 10 to 25 mol, based on total acid residues. %to be.

The sulfopolyesters of the present invention include one or more diol moieties that may include aliphatic, alicyclic, and aralkyl glycols. Alicyclic diols, for example 1,3- and 1,4-cyclohexanedimethanol, may exist as their pure cis or trans isomers or as mixtures of cis and trans isomers. Non-limiting examples of low molecular weight polyethylene glycols, such as n 2 to 6, are diethylene glycol, triethylene glycol, and tetraethylene glycol. Of these low molecular weight glycols, diethylene and triethylene glycol are most preferred. The sulfopolyester can optionally include branched monomers. Examples of branched monomers are as described herein above. Additional examples of branched monomer concentration ranges are 0 to about 20 mol% and 0 to about 10 mol%. The sulfopolyester of the novel method of the present invention has a T _g of 25 ° C or higher. Additional examples of glass transition temperatures exhibited by sulfopolyesters are 30 ° C or higher, 35 ° C or higher, 40 ° C or higher, 50 ° C or higher, 60 ° C or higher, 65 ° C or higher, 80 ° C or higher, and 90 ° C or higher. Other T _g are possible, but typical glass transition temperatures of the dry sulfopolyester of the present invention are about 30 ° C, about 48 ° C, about 55 ° C, about 65 ° C, about 70 ° C, about 75 ° C, about 85 ° C, and about 90 ° C.

Water-dispersible fibers are produced by a melt blow process. The polymer is melted in an extruder and pushed through a die. The extrudate exiting the die is quickly thinned to ultrafine diameter by hot, high-speed air. Fiber orientation, cooling rate, glass transition temperature (T _g ), and crystallization rate are important because they affect the viscosity and processing properties of the polymer while the extrudate is tapered. Filaments are collected on renewable surfaces such as moving belts, cylindrical drums, rotating mandrels, and the like. Predrying of pellets (if required), extruder zone temperature, melt temperature, screw design, processing speed, air temperature, air flow (velocity), die air gap and setback, nose tip hole size, die temperature, from die Collector distance (die-to-collector; DCP), quench environment, collector speed, and post-treatment are all factors affecting article characteristics such as filament diameter, basis weight, web thickness, pore size, softness, and shrinkage. In addition, high-speed air can be used to move the filaments in a somewhat random fashion to cause a wide range of interlacing. When the transfer belt moves under the die, the nonwoven fabric can be made by a combination of overlapping laydown of filaments, mechanical cohesiveness, and thermal bonding. Overblown onto another substrate, such as a spin-bonded or backing layer, is also possible. When the filament is wound on a rotating mandrel, a cylindrical article is formed. Water-dispersible fiber lay-down can also be produced by a spin-bonding process.

Therefore, the present invention also

(A) (i) one or more dicarboxylic acid residues;

(ii) from about 4 to about 40 mole percent, based on total repeating units, of a sulfomonomer residue having at least one metal sulfonate group attached to an aromatic or cycloaliphatic ring and two functional groups that are hydroxyl, carboxyl, or a combination thereof. One or more;

(iii) 20% by mole or more based on total diol residue is a die of poly (ethylene glycol) having a structure of H- (OCH ₂ -CH ₂ ) _n -OH (where n is an integer ranging from 2 to about 500) At least one residue; And

(iv) 0 to about 25 mole% of branched monomer residues having at least 3 functional groups, hydroxyl, carboxyl, or combinations thereof, based on total repeat units

A water-dispersible polymer composition comprising: wherein the sulfopolyester has a glass transition temperature (T _g ) of 25 ° C. or higher; the polymer composition contains less than 10% by weight of a pigment or filler based on the total weight of the polymer composition) Heating to a temperature higher than its pour point;

(B) melt-spinning the filament; And

(C) forming a nonwoven fabric by overlapping and collecting the filaments of step (B).

It provides a method for producing a water-dispersible nonwoven fabric comprising a.

As described herein above, the water-dispersible polymer can optionally be blended with sulfopolyester. In addition, non-water-dispersible polymers can optionally be blended with sulfopolyesters to form blends that are immiscible blends. Dicarboxylic acids, sulfomonomers, and branched monomer residues are as described above. The sulfopolyester has a T _g of 25 ° C or higher. Additional examples of glass transition temperatures exhibited by sulfopolyesters are 30 ° C or higher, 35 ° C or higher, 40 ° C or higher, 50 ° C or higher, 60 ° C or higher, 65 ° C or higher, 80 ° C or higher, and 90 ° C or higher. Other T _g are possible, but typical glass transition temperatures of the dry sulfopolyester of the present invention are about 30 ° C, about 48 ° C, about 55 ° C, about 65 ° C, about 70 ° C, about 75 ° C, about 85 ° C, and about 90 ° C.

In certain embodiments of the present invention, a water-wet microfiber product (wet wrap) prepared after cutting, washing, and dewatering excess water of the multicomponent fiber is directly to the wet-laid nonwoven process (i.e., without additional drying process). Is used. Using the wet wrap product directly in the wet-laid nonwoven process avoids the need for complete drying of the wet wrap, thereby saving significant energy and equipment costs. If the wet wrap production facility is located away from the wet-laid nonwoven manufacturing facility, the wet wrap may be packaged and transported from the wet wrap production site to the nonwoven production site. This wet wrap composition is described in detail immediately below.

One embodiment of the present invention relates to a wet wrap composition comprising water and a plurality of synthetic fibers. Water may constitute 50, 55 or 60% by weight or more and / or 90, 85 or 80% by weight or less of the wet wrap composition. The synthetic fiber may constitute 10, 15 or 20% by weight or more and / or 50, 45 or 40% by weight or less of the wet wrap composition. The water and the synthetic fibers can be combined to make up 95, 98 or 99% by weight or more of the wet wrap composition. The synthetic fiber may have a length of 0.25, 0.5 or 1 mm or more and / or 25, 10 or 2 mm or less. The synthetic fibers may have a minimum transverse dimension of 0.1, 0.5 or 0.75 microns or more and / or 10, 5 or 2 microns or less.

As used herein, “minimum transverse dimension” is defined as the minimum dimension of a fiber measured perpendicular to the axis of extension of the fiber by an external caliper method. As used herein, "maximum transverse dimension" is defined as the maximum dimension of a fiber measured perpendicular to the axis of extension of the fiber by an external caliper method. 1A, 1B, and 1C show how these dimensions can be measured at various fiber cross sections. 1A, 1B and 1C, "TD _minimum " is the minimum transverse dimension and "TD _maximum " is the maximum transverse dimension. As used herein, the "outer caliper method" is a method for measuring the outer dimension of a fiber, wherein the measured dimension is a distance between two parallel lines on the same plane, where the fiber is located between the two parallel lines, and each parallel line is a fiber. It is generally in contact with the outer surface of the fiber on the opposite side. All fiber dimensions provided herein (eg, length, minimum transverse dimension and maximum transverse dimension) are average dimensions of fibers belonging to the specified group.

The wet wrap composition may further include a fiber finishing composition in an amount of 10, 50 or 100 ppmw or more and / or 1,000, 500, 250 ppmw or less. In one embodiment, the fiber final treatment composition can include oil, wax and / or fatty acids. In another embodiment, the fiber final treatment composition may include natural fatty acids and / or natural oils. In another embodiment, the fiber final treatment composition comprises mineral oil, stearate ester, sorbitan ester and / or foot oil. In another embodiment, the fiber finish composition comprises mineral oil.

The wet wrap composition may include 0.001, 0.01, or 0.1% by weight or more, and / or 5, 2, or 1% by weight or less of a water dispersible polymer. In one embodiment, the water-dispersible polymer can include one or more sulfopolyesters. The sulfopolyester was previously described herein.

The sulfo polyester

(A) about 50 to about 96%, based on total acid residues, of at least one residue of dicarboxylic acid comprising terephthalic acid and isophthalic acid,

(B) about 4 to about 40 mole percent, based on total acid residues, of a sulfomonomer residue having at least one sulfonate group attached to an aromatic or cycloaliphatic ring and two functional groups, hydroxyl, carboxyl, or combinations thereof. One or more, and

(C) one or more diol residues

It includes.

The sulfopolyester has a glass transition temperature (Tg) of 40 ° C. or higher or 50 ° C. or higher, and is measured at a concentration of 0.5 g of sulfopolyester in 40 ° C. and 100 ml of solvent in a 60/40 parts by weight solution of a phenol / tetrachloroethane solvent. Has an intrinsic viscosity of 0.2 dL / g or more, and may have a melt viscosity of less than about 12,000, 8,000, or 6,000 poise when measured at a strain of 1 rad / sec at 240 ° C.

The water non-dispersible synthetic polymers of the wet wrap composition are polyolefin, polyester, copolyester, polyamide, polylactide, polycaprolactone, polycarbonate, polyurethane, cellulose ester, acrylic, polyvinyl chloride and their It can be selected from the group consisting of blends. In one embodiment, the water non-dispersible synthetic polymer is selected from the group consisting of polyethylene terephthalate homopolymer, polyethylene terephthalate copolymer, polybutylene terephthalate, polypropylene terephthalate, nylon 6, nylon 66 and blends thereof. do.

The wet wrap composition can be prepared by a method comprising the following steps (A)-(D):

(A) preparing a multicomponent fiber having a spinning denier of less than 15 dpf, comprising at least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester;

(B) cutting the multicomponent fiber into cut multicomponent fibers having a length of less than 25 mm;

(C) preparing a synthetic fiber slurry in a sulfopolyester dispersion comprising water and at least a portion of the sulfopolyester by contacting the cut multicomponent fiber with water to remove the sulfopolyester; And

(D) preparing a wet wrap composition by removing at least a portion of the sulfopolyester dispersion from the slurry.

As discussed above, wet wrap compositions can be used directly in wet-laid processes to produce nonwoven articles. To use the wet wrap during the wet-laid process, the wet wrap composition is transported from the manufacturing site to the wet-laid nonwoven zone. The wet wrap composition can be mixed with additional fibers just prior to the wet-laid nonwoven zone and / or wet-laid. The additional fiber can be selected from the group consisting of cellulose fiber pulp, inorganic fiber, polyester fiber, nylon fiber, lyocell fiber, polyolefin fiber, rayon fiber, cellulose ester fiber and combinations thereof.

As part of a wet-laid process, the wet wrap composition can be mixed with dilution water upstream just prior to the wet-laid nonwoven zone and / or wet-laid nonwoven zone. The dilution water and the wet wrap may be mixed in an amount of 50, 75, 90 or 95 parts by weight or more of the diluted water per 1 part of the wet wrap.

In another embodiment of the present invention, a method for producing a microfiber product stream is provided, as shown in FIGS. 2, 3A, 3B, and 4. Multicomponent fibers are as already mentioned herein. Additional disclosures relating to multicomponent fibers are provided in the following patents and patent applications: US Patent 6,989,193; 7,635,745; 7,902,094; 7,892,993; 7,687,143; And US Patent Application 12 / 199,304; 12 / 909,574; 13 / 273,692; 13 / 273,648; 13 / 273,710; 13 / 273,720; 13 / 273,929, 13 / 273,937; 13 / 273,727, 13 / 273,737; 13 / 273,745; 13 / 273,749; 12 / 966,502; 12 / 966,507; 12 / 975,450; 12 / 975,452; 12 / 975,456; 13 / 053,615; 13 / 352,362; 13 / 433,812; 13 / 433,854; 61 / 471,259; 61 / 472,964; And 61 / 558,744. The above documents are incorporated herein by reference to the extent that they are inconsistent with the contents mentioned herein.

The terms “wet wrap” and “microfiber product stream” will be used interchangeably herein.

In one embodiment of the present invention shown in Figure 2, a method of making a microfiber product stream is provided. This way

(A) Short-cut multi-component fibers 101 having a length of less than 25 mm are contacted with the heated aqueous stream 801 in the fiber opening zone 400 to remove a portion of the water-dispersible sulfopolyester and open microfibers. The step of producing a slurry 401, wherein the short-cut multicomponent fiber comprises at least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer that is immiscible with the water dispersible sulfopolyester, The heated aqueous stream 801 is at a temperature of 40 ° C. or higher, and the open microfiber slurry 401 comprises water, microfiber and water dispersible sulfopolyester; And

(B) sending the open microfiber slurry 401 to a first solid-liquid separation zone 500 to generate a microfiber product stream 503 and a first mother liquor stream 501, wherein the first mother liquor Stream 501 comprises water and water dispersible sulfopolyester

It includes.

In this embodiment of the present invention, the fiber slurry zone 200, mixing zone 300 and fiber opening zone 400 as shown in FIG. 4 are combined in one unit operation in the opening process zone 1100. The open process zone 1100 includes a fiber open zone 400.

The treated aqueous stream 103 used in this method can be generated by sending the aqueous stream 102 to the aqueous treatment band 1000 to produce a treated aqueous stream 103. The aqueous stream contains water. In embodiments of the present invention, the monovalent metal cation in the treated aqueous stream 103 can be less than about 1000 ppm by weight, less than about 500 ppm by weight, less than about 100 ppm by weight, or less than about 50 ppm by weight. Removal of divalent and polyvalent metal cations from aqueous stream 102 is one function of aqueous treatment zone 1000. In other embodiments of the invention, the concentration of the divalent and polyvalent metal cations is less than about 50 ppm by weight, less than about 25 ppm by weight, less than about 10 ppm by weight, or less than about 5 ppm by weight. The temperature of the stream 103 may range from groundwater temperature to about 40 ° C.

Treatment of the aqueous stream 102 in the aqueous treatment zone 1000 can be accomplished by any method known in the art. In one embodiment, the aqueous treatment zone 1000 includes distillation equipment to generate and condense water vapor to produce a treated aqueous stream 103. In another embodiment, water can be sent to a reverse osmosis membrane separation zone to remove monovalent and divalent metal cations from the water to produce a treated aqueous stream 103. In another embodiment, water is sent to the ion exchange resin, producing a treated aqueous stream 103 with metal concentrations of an acceptable low concentration. In another embodiment, the water is sent to a commercial water softening device to produce a treated aqueous stream 103 with acceptable concentrations of divalent and polyvalent metal ions. It should be understood that any combination of these water treatment options is used to achieve the required treatment water characteristics.

The treated aqueous stream 103 can be sent to any required location in the process. In one embodiment, a portion of stream 103 is sent to first solid-liquid separation zone 500 to act as a wash liquor for the solids contained in cloth wash liquor and / or first solid-liquid separation zone 500. .

In one embodiment, at least a portion of the treated aqueous stream 103 is sent to a heat exchanger zone 800 to produce a heated aqueous stream. One function of the heat exchanger zone 800 is to produce a heated aqueous stream 801 at a specific controlled temperature.

In one embodiment, stream 800 that can be fed to heat exchanger zone 800 is treated aqueous stream 103 and second mother liquor stream 601. In another embodiment, stream 800 that can be fed to heat exchanger zone 800 is treated aqueous stream 103, part of first recovered water stream 703, first mother liquor stream 501 And a portion of the second mother liquor stream 601.

Devices known in the art for controlling the temperature of stream 801, for example, without limitation, any heat exchanger using a stream used to provide some of the energy required, used to provide some of the energy required Any heat exchanger using a heat transfer fluid, any heat exchanger using an electrical heating element used to provide some of the required energy, and steam condensed and condensate mixed with water supplied to the heat exchanger zone 800 Any container or tank using direct steam injection can be used. The multicomponent fiber stream 90 is sent to a fiber cutting zone 100 to produce a cut multicomponent fiber stream 101. The multicomponent fiber can have any multicomponent structure known in the art. Multicomponent fibers include water dispersible sulfopolyesters and water non-dispersible polymers, as described herein above.

The multicomponent fiber stream 90 can be cut using any device known in the art to produce a cut multicomponent fiber stream 101. In one embodiment, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 50 mm. In other embodiments, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 25 mm, less than about 20 mm, less than about 15 mm, less than about 10 mm, less than about 5 mm, or about 2.5 mm. Less than.

The cut multi-component fiber stream 101 and a portion of the heated treated aqueous stream 801 are sent to a fiber opening zone 400 to produce an open microfiber slurry 401. One function of the fiber opening zone 400 is to separate the water-dispersible polymer from the cut multi-component fibers so that at least a portion of the water non-dispersible polymer microfibers are separated from the cut multi-component fiber fibers and opened micro It is to be suspended in the fiber slurry 401. In another embodiment of the present invention, about 50 to about 100% by weight of the water non-dispersible polymer microfiber contained in the cut multicomponent fiber slurry 201 can be added to the open microfiber slurry 401. Suspended as a non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber. In other embodiments, about 75 to about 100 weight percent, about 90 to about 100 weight percent, or about 95 to about 100 weight percent of the water non-dispersible polymer microfiber contained in the cut multicomponent fiber stream 201 Is suspended in the open microfiber slurry 401 as a water non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber.

The diameter or denier of the starting cut multicomponent fibers in stream 201 affects the degree to which water-dispersible sulfopolyester is separated from the multicomponent fibers in fiber open zone 400. Typical multicomponent fiber types generally have diameters ranging from about 12 microns to about 20 microns. Useful multicomponent fibers can have a larger starting diameter of about 40 microns or larger in diameter size. The time required to separate the desired amount of water dispersible sulfopolyester from the cut multicomponent fiber increases as the diameter of the cut multicomponent fiber in stream 201 increases.

In this embodiment of the present invention, the fiber slurry zone 200, the mixing zone 300 and the fiber opening area 400 as shown in FIG. 4 are combined to be achieved in one unit operation as shown in FIG. . In this embodiment, the cut multi-component fiber stream 101 is sent directly in a single unit operation, where it is mixed with the heated aqueous stream 801 within the fiber open area 400. For example, in a single batch mixing device in which the cut multi-component fiber stream 101 and the heated aqueous stream 801 are added directly to the fiber opening region 400, opening or washing of the cut multi-component fiber stream is achieved. There is a batch mixing device. The fiber opening zone can include one or more mixing tanks. In this embodiment, the combined function of the zones 200, 300 and 400 can be achieved in the continuous stirred tank reactor shown in Figure 5b aoc Figure 5c. In this embodiment, the combined functions of the zones 200, 300, and 400 are functional of residence time, temperature, and mixed shear forces required for proper functioning of the zones 200, 300, and 400. It can be achieved in any batch or continuous mixing apparatus that can achieve the requirements.

The residence time, temperature and shear force in the fiber opening zone 400 also influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. Conditions affecting the opening process in the fiber opening zone 400 include residence time, slurry temperature and shear force, where the water temperature in the fiber opening zone 400, the range of residence time, and the degree of shear applied, are -To the extent that the dispersible polymer microfibers are separated and suspended in the continuous aqueous phase of the open microfiber slurry 401, it is governed by the need to separate the water dispersible sulfopolyester from the starting multicomponent fiber.

The residence time, temperature and shear force in the fiber opening zone 400 influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. The temperature of the fiber opening zone 400 may range from about 55 to about 100 ° C, from about 60 to about 90 ° C, or from about 65 to about 80 ° C. The residence time in the fiber opening zone 400 can range from about 5 minutes to about 10 seconds, from about 3 minutes to about 20 seconds, or from about 2 minutes to about 30 seconds. Sufficient mixing is maintained in the fiber open zone 400, so that the suspension of the cut water non-dispersible polymer microfibers is maintained such that settling of the cut microfibers is minimal. In another embodiment of the present invention, the mass per unit time of the cut water non-dispersible polymer microfibers in the fiber opening zone 400 is the mass per unit time of the water non-dispersible polymer microfibers entering the zone 400. Less than about 5%, less than about 3% of the mass per unit time of the number of non-dispersible polymer microfibers entering the zone 400, or of the number of non-dispersible polymer microfibers entering the zone 400 Less than about 1% of the mass per unit time.

Fiber opening in the fiber opening zone 400 can be achieved in any device that can allow for an acceptable residence time, temperature and mixing range. Examples of suitable devices include, but are not limited to, a stirred batch tank as shown in FIGS. 6B and 6C, a continuous stirred tank reactor, and a flow sufficient to minimize solid settling from the slurry as shown in FIG. 6A. Pipes are included. One example of a unit operation to achieve fiber opening in fiber opening zone 400 is a plug flow reactor, where heated multicomponent fiber slurry 301 is a zone 400 plug flow device, typically circular. It is sent by pipe or conduit. The residence time of the material in the plug flow device is calculated by dividing the filled volume in the device by the volume flow rate in the device. Material velocity within the device is defined as the cross-sectional area of the flow channel divided by the volumetric flow of liquid through the device.

In another embodiment of the invention, the fiber opening zone 400 may have a material flow rate in the pipe ranging from 0.1 to about 20 ft / sec, 0.2 to about 10 ft / sec, or about 0.5 to about 5 ft / sec. It may include pipes or conduits. For a flow of fluid or slurry in a pipe or conduit, the Reynolds number is a dimensionless number useful for describing the turbulence or motion of a fluid eddy current that is irregular for both direction and time. For flow in a pipe or tube, the Reynolds number is generally defined as follows:

In the above formula,

D _H Is the hydraulic diameter (L) of the pipe (in meters);

Q is the volumetric flow rate (m ³ / s),

A is the pipe cross-sectional area (m ² ),

υ is the average velocity of the object relative to the fluid (SI unit: m / s),

μ is the dynamic viscosity of the fluid (Pa · s or N · s / m ² or kg / (m · s)),

v is the dynamic viscosity (v = μ / ρ) (m ² / s),

ρ is the density of the fluid (kg / m ³ ).

For flows in pipes of diameter D , experimental observations show that for fully developed flows, laminar flow occurs when Re _D is less than 2000, and turbulent flow when Re _D is greater than 4000. . Between 2300 and 4000, layered and turbulent flows are possible ("transition" flows) depending on other factors, such as pipe roughness and flow uniformity.

The fiber open zone 400 may include pipes or conduits to facilitate the opening process, and the Reynolds number of flows through the pipes or conduits in the fiber open zone 400 ranges from about 2,100 to about 6,000, about 3,000 To about 6,000, or about 3,500 to about 6,000. In other embodiments, the fiber opening zone 400 can include a pipe or conduit to facilitate the opening process, wherein the Reynolds number of flows through the pipe or conduit is greater than 2,500, greater than about 3,500 or greater than about 4,000 to be.

The fiber opening zone 400 includes a pipe or conduit with a mixing device inserted in the pipe or conduit. The device may include an in-line mixing device. The in-line mixing device can be a static mixer without moving parts. In another embodiment, the in-line mixing device includes a movable portion. Non-limiting, such elements are mechanical devices for the purpose of imparting more mixed energy to the heated multicomponent fiber slurry 301, not achieved by flow through the pipe. The device can be inserted at the beginning of a pipe section used as a fiber opening zone, at the end of the pipe section, or at any location within the pipe flow path.

An open fiber slurry stream 401 comprising water non-dispersible polymer microfibers, water and water dispersible sulfopolyester is sent to a first solid-liquid separation zone 500, to provide a microfiber and a first mother liquor stream 501. A microfiber product stream 503 can be produced. In one embodiment, the first mother liquor stream 501 comprises water and water dispersible sulfopolyester.

The weight percent of solids in the open fiber slurry stream 401 can range from about 0.1 to about 20 weight percent, about 0.3 to about 10 weight percent, about 0.3 to about 5 weight percent, or about 0.3 to about 2.5 weight percent .

 The weight percent of solids in the microfiber product stream 503 can range from about 10 to about 65 weight percent, from about 15 to about 50 weight percent, from about 25 to about 45 weight percent, or from about 30 to about 40 weight percent.

Separating the microfiber product stream 503 from the open fiber slurry stream 401 can be accomplished by any method known in the art. In one embodiment, a wash stream 103 comprising water is sent to a first solid-liquid separation zone 500. The wash stream 103 can be used to wash the microfiber product stream in filter cloth media in the first solid-liquid separation zone 500 and / or the first solid-liquid separation zone 500 to produce a wash liquor stream 502. Fractions up to 100% by weight of the liquor stream 502 can be combined with the open fiber slurry stream 401 before entering the first solid-liquid separation zone 500. Fractions up to 100% by weight of the liquor stream 502 may be sent to a second solid-liquid separation zone 600. The liquor stream 502 may contain microfibers. In one embodiment, the g of microfiber mass passing through a filter medium having an opening of 200 microns or less in the first solid-liquid separation zone 500 ranges from about 1 to 2 g per cm ² of filter area. In other embodiments of the invention, the filter opening of the filter media in the first solid-liquid separation zone 500 may range from about 43 microns to 3000 microns, about 100 microns to 2000 microns, or about 500 microns to 2000 microns.

Separating the microfiber product stream from the microfiber slurry opened in the first solid-liquid separation zone 500 can be accomplished by one or several solid-liquid separation devices. Separation in the first solid-liquid separation zone 500 can be achieved by a batch and / or solid-liquid separation device or devices operated in a continuous manner. Suitable solid-liquid separation devices in the first solid-liquid separation zone 500 may include, but are not limited to, one of the following: perforated basket centrifuge, continuous vacuum belt filter, batch vacuum nutschfilter, batch perforated Settling tank, twin wire dewatering device, continuous horizontal belt filter with compression area, non-vibration inclined screen device with wedge wire filter media, continuous vacuum drum filter, dewatering conveyor belt, etc.

In one embodiment, the first solid-liquid separation zone 500 includes a twin wire dewatering device, wherein an open fiber slurry stream 401 is sent to the tapering gap between a pair of moving filter cloths moving in the same direction. . In the first zone of the twin wire dewatering device, water is drained due to gravity from the open fiber slurry stream 401 and from every narrow gap between the two moving filter cloths. In the downstream zone of the twin wire dewatering device, two filter cloths and a microfiber material between the two filter cloths are compressed more than once to mechanically reduce moisture in the microfiber material. In one embodiment, mechanical dewatering is accomplished by passing the two filter cloths and the contained microfiber material through a set of one or more rollers that exert a compressive force on the two filter cloths and the microfiber material between them. In another embodiment, mechanical dewatering is achieved by passing the two filter cloths and microfiber material through one or more sets of pressure rollers.

In another embodiment of the invention, the force exerted by mechanical dewatering for each set of pressure rollers ranges from about 25 to about 300 lbs per linear inch of filter media width, from about 50 to about 200 per linear inch of filter media width. in the lb range, or from about 70 to about 125 lb per linear inch of filter media width. The microfiber product stream 503 is discharged from the twin wire dewatering apparatus as the two filter cloths are separated and split in the solid discharge zone of the twin wire dewatering apparatus. The thickness of the microfiber material discharged may range from about 0.2 to about 1.5 inches, from about 0.3 to about 1.25 inches, or from about 0.4 to about 1 inch. In one embodiment, a stream of liquor comprising water is continuously applied to the filter medium. In another embodiment, a stream of liquor comprising water is periodically applied to the filter medium.

In another embodiment, the first solid-liquid separation zone 500 includes a belt filter device comprising a gravity drainage zone and a pressurized dehydration zone as illustrated in FIG. 7. The open microfiber slurry 401 is sent to a tapering gap between a pair of moving filter cloths moving in the same direction, first passing through the gravity drainage zone and then in a serpentine arrangement as shown in Figure 6B. It passes through the pressurized dehydration zone or press zone included. As the belt is fed through the rollers, water escapes from the solid. In this process, when the belt passes through the final pair of rollers, the filter cloth is separated and solid is discharged from the belt filter device.

In another embodiment of the present invention, at least a portion of the water contained in the first mother liquor stream 501 comprising water and water dispersible sulfopolyester is recovered and recycled. The first mother liquor stream 501 may be recycled to the first solid-liquid separation zone 500. Depending on the efficiency of the first solid-liquid separation zone in the removal of water non-dispersible polymer microfibers, the first mother liquor stream 501 may be a fiber open zone 400, or a heat exchanger zone before entering the zone 400. It can be recycled to (800). The first mother liquor stream 501 may contain a small amount of solids including water non-dispersible polymer microfibers due to breakthrough and cloth washing. In one embodiment, g of the water non-dispersible polymer microfiber material passing through the filter medium in the first solid separation zone having an opening of 2000 microns or less ranges from about 1 to about 2 g per cm ² of filter area. . Before sending the first mother liquor stream 501 to the first enrichment zone 700 and the heat exchange zone 800 (in these zones, a number of non-dispersible polymer microfiber solids with negative effects can be collected and accumulated). It is desirable to minimize the number of non-dispersible polymer microfibers in stream 501.

The second solid-liquid separation zone 600 removes at least a portion of the water non-dispersible polymer microfiber solids present in the first mother liquor stream 501 to thereby remove the second wet cake comprising the water non-dispersible microfibers. It can function to generate a stream 602 and a second mother liquor stream 601 comprising water and water dispersible sulfopolyester.

In one embodiment, the second mother liquor stream 601 is sent to the first enrichment zone 700 and / or heat exchanger zone 800, where the second mother liquor stream 601 is sent to the first enrichment zone 700. ) May be in the range of 0 to 100%, and the remainder of the stream is sent to the heat exchanger zone 800. The second mother liquor stream 601 can be recycled to the fiber open zone 400, or to the heat exchanger zone 800 before being sent to the zone 400. The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Any portion of the second mother liquor stream 601 sent to the first concentration zone is subjected to a separation process to produce a first recovered water stream 703 and a first polymer concentrate stream 702 rich in water dispersible sulfopolyester. Produced, wherein the weight percent of the water dispersible sulfopolyester in the first polymer concentrate stream 702 can range from about 5 to about 85 weight percent, from about 10 to about 65 weight percent, or from about 15 to about 45 weight percent. have. The first recovered water stream 703 may be recycled to the fiber open zone 400, or to the heat exchanger zone 800 before being sent to the zone 400. The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Water may be removed from the second mother liquor stream 601 in the first enrichment zone 700 by any method known in the art to produce a first polymer enrichment stream 702. In one embodiment, removal of water includes an evaporation process by boiling water in a batch or continuous evaporation apparatus. For example, one or more thin film evaporators can be used for this application. In another embodiment, the first polymer concentrate stream 702 can be produced using membrane technology comprising nanofiltration media. In another embodiment, a process comprising an extraction device can be used to extract the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. A combination of evaporation, membrane, and extraction steps can be used to separate the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. The first polymer concentrate stream 702 can then be discharged out of the process.

In one embodiment, the first polymer concentrate stream 702 is sent to a second concentration zone 900, whereby the melted polymer stream 903 comprising water-dispersible sulfopolyester, wherein the weight percent of polymer is about 95 to about 100%) and steam stream 902 comprising water. In one embodiment, the stream 903 comprises water dispersible sulfopolyester. Suitable devices for the second concentration zone 900 include any device known in the art that can supply an aqueous dispersion of a water dispersible polymer and can produce a 95% to 100% water dispersible polymer stream 903. . This embodiment includes feeding an aqueous dispersion of the water-dispersible sulfopolyester polymer to the second concentration zone 900. The temperature of the feed stream is typically below 100 ° C.

In one embodiment, the second enrichment zone 900 is one or more devices characterized by a jacketed tubular shell containing a rotating transport screw, wherein the transport screw is heated with heat transfer fluid or steam Transport and high shear mixing elements). The jacket or shell is evacuated to allow steam to be removed. The shell jacket can be banded to allow different temperature set points along the length of the device. During continuous operation, the first polymer concentrate stream 702 includes water and water dispersible sulfopolyester, and is continuously fed to the second concentration zone 900. Within the device, there are at least three distinct and different forms of material in the steady state. The material in the device is first present as an aqueous dispersion of a water-dispersible sulfopolyester polymer. As the aqueous dispersion of sulfopolyester polymer moves through the device, water evaporates due to the heat of the jacket and the inner screw. When sufficient water is evaporated, the material becomes a second form comprising a viscous plug at a temperature lower than the melting point of the sulfopolyester polymer. The aqueous dispersion cannot flow past this viscous plug and is limited to the first aqueous dispersion zone of the device. Due to the heat of the jacket, the heat of the internally heated screw, and the heat due to the mixing shear force of this high-viscosity plug material, substantially all of the water present at this location is evaporated and the temperature is maintained until the melting temperature of the sulfoester is reached. Ascending, a third final physical form of the material comprising the molten sulfopolyester polymer is produced in the device. The molten sulfopolyester polymer is then exited the device through an extrusion die, typically cooled and cut into pellets in any manner known in the art. It should be understood that the device for the second enrichment zone 900 described above can also be operated in a batch mode, where the continuous of the viscous plug material and finally the sulfopolyester melt, starting with the aqueous dispersion throughout the length of the device. Three physical forms of the material described above occur in different time zones in sequence.

In one embodiment, the vapor generated in the second concentration zone 900 can be condensed and sent to the heat exchanger zone 800 and / or disposed of and / or sent to the wash stream 103. In another embodiment, condensed vapor stream 902 comprising water vapor can be sent to heat exchanger zone 800 to provide at least a portion of the energy required to generate the temperature required for stream 801. The molten polymer stream 903 comprising a water-dispersible polymer comprising sulfopolyester in the molten phase can be cooled and chopped into pellets by any method known in the art.

Impurities may be introduced into the process, and concentrated in water that is recovered and recycled. The concentration of impurities in the second mother liquor 601 and the first recovered water stream 701 may be adjusted to an acceptable level using one or more purge streams 603 and 701. In one embodiment, a portion of the second mother liquor stream 601 can be isolated and purged from the process. In one embodiment, a portion of the first recovered water stream 701 can be isolated and purged from the process.

In another embodiment of the present invention, a method for producing a microfiber product stream as shown in FIG. 3A is provided. This way

(A) contacting the short-cut multi-component fiber 101 having a length of less than 25 mm in the fiber slurry zone 200 with the treated aqueous stream 103 to produce a short-cut multi-component fiber slurry 201 Wherein, the short-cut multicomponent fiber 101 comprises at least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer that is immiscible with the water dispersible sulfopolyester, and the treated aqueous stream Step 103 is a temperature of 40 ° C. or higher;

(B) The short-cut multi-component fiber slurry 201 and the heated aqueous stream 801 are contacted in the fiber opening zone 400 to remove a portion of the water-dispersible sulfopolyester, thereby opening the microfiber slurry 401. A step of producing, wherein the open microfiber slurry comprises water non-dispersible polymer microfibers, water dispersible sulfopolyester and water; And

(C) sending the opened microfiber slurry 401 to a first solid-liquid separation zone 500 to generate a microfiber product stream 503 and a first mother liquor stream 501, wherein the first mother liquor Stream 501 comprises water and water dispersible sulfopolyester

It includes.

In this embodiment of the present invention, the mixing zone 300 and the fiber opening area 400 as shown in FIG. 4 are combined in one unit operation in the opening process zone 1100. The open process zone 1100 includes a fiber slurry zone 200 and a fiber opening zone 400.

The processed aqueous stream 103 for use in this method can be generated by sending the aqueous stream 102 to the aqueous processing band 1000 to generate a processed aqueous stream 103. The aqueous stream contains water. In embodiments of the present invention, the monovalent metal cation in the treated aqueous stream 103 can be less than about 1000 ppm by weight, less than about 500 ppm by weight, less than about 100 ppm by weight, or less than about 50 ppm by weight. Removal of divalent and polyvalent metal cations from aqueous stream 102 is one function of aqueous treatment zone 1000. In other embodiments of the invention, the concentration of the divalent and polyvalent metal cations is less than about 50 ppm by weight, less than about 25 ppm by weight, less than about 10 ppm by weight, or less than about 5 ppm by weight. The temperature of the stream 103 may range from groundwater temperature to about 40 ° C.

Treatment of the aqueous stream 102 in the aqueous treatment zone 1000 can be accomplished by any method known in the art. In one embodiment, the aqueous treatment zone 1000 includes distillation equipment to generate and condense water vapor to produce a treated aqueous stream 103. In another embodiment, water can be sent to a reverse osmosis membrane separation zone to remove monovalent and divalent metal cations from the water to produce a treated aqueous stream 103. In another embodiment, water is sent to the ion exchange resin, producing a treated aqueous stream 103 with metal concentrations of an acceptable low concentration. In another embodiment, the water is sent to a commercial water softening device to produce a treated aqueous stream 103 with acceptable concentrations of divalent and polyvalent metal ions. It should be understood that any combination of these water treatment options is used to achieve the required treatment water characteristics.

The treated aqueous stream 103 can be sent to any required location in the process. In one embodiment, a portion of stream 103 is sent to first solid-liquid separation zone 500 to act as a wash liquor for the solids contained in cloth wash liquor and / or first solid-liquid separation zone 500. .

In one embodiment, at least a portion of the treated aqueous stream 103 is sent to a heat exchanger zone 800. In another embodiment, at least a portion of the treated aqueous stream 103 is sent to a fiber slurry zone 200. In another embodiment, at least a portion of the treated aqueous stream 103 is sent to a heat exchanger zone 800 and at least a portion of the treated aqueous stream 103 is sent to a fiber slurry zone 200. One function of the heat exchanger zone 800 is to produce a heated aqueous stream 801 at a specific controlled temperature.

In one embodiment, stream 800 that can be fed to heat exchanger zone 800 is treated aqueous stream 103 and second mother liquor stream 601. In another embodiment, stream 800 that can be fed to heat exchanger zone 800 comprises treated aqueous stream 103, first recovered water stream 703, first mother liquor stream 501, and 2 The mother liquor stream 601 is included.

Devices known in the art for controlling the temperature of stream 801, for example, without limitation, any heat exchanger using a stream used to provide some of the energy required, used to provide some of the energy required Any heat exchanger using a heat transfer fluid, any heat exchanger using an electrical heating element used to provide some of the required energy, and steam condensed and condensate mixed with water supplied to the heat exchanger zone 800 Any container or tank using direct steam injection can be used. The multicomponent fiber stream 90 is sent to a fiber cutting zone 100 to produce a cut multicomponent fiber stream 101. The multicomponent fiber can have any multicomponent structure known in the art. Multicomponent fibers include water dispersible sulfopolyesters and water non-dispersible polymers, as described herein above.

The multicomponent fiber stream 90 can be cut using any device known in the art to produce a cut multicomponent fiber stream 101. In one embodiment, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 50 mm. In other embodiments, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 25 mm, less than about 20 mm, less than about 15 mm, less than about 10 mm, less than about 5 mm, or about 2.5 mm. Less than.

A portion of the cut multi-component fiber stream 101 and a heated treated aqueous stream 801 is sent to a fiber slurry zone 200 to cut a multi-component fiber slurry 201 comprising water and cut multi-component fibers. Produces In one embodiment, the weight percent of the cut microfibers in the cut multicomponent fiber slurry 201 is from about 35 weight percent to about 1 weight percent, from about 25 weight percent to about 1 weight percent, from about 15 weight percent to about 15 weight percent 1% by weight, or from about 7% to about 1% by weight.

The temperature of the cut multicomponent fiber slurry 201 may range from about 5 to about 45 ° C, from about 10 to about 35 ° C, or from about 10 to about 25 ° C. In one embodiment, the fiber slurry zone 200 includes a tank with sufficient agitation to produce a suspension in a continuous aqueous phase of cut multicomponent fibers.

Any device known in the art to be suitable for mixing solids with water and maintaining the suspension in the resulting aqueous phase of the resulting cut multicomponent fiber can be used in the fiber slurry zone 200. The fiber slurry zone 200 can include a batch or continuous mixing device operated in a continuous or batch mode. Suitable devices for use in the fiber slurry zone 200 include, but are not limited to, a hydro-pulping machine, a continuously stirred tank reactor, and a tank with agitation operated in a batch mode.

Subsequently, the cut multicomponent fiber slurry 201 can be sent to the fiber opening zone 400. One function of the fiber opening zone 400 is to separate the water-dispersible polymer from the cut multi-component fibers so that at least a portion of the water non-dispersible polymer microfibers are separated from the cut multi-component fiber fibers and opened micro It is to be suspended in the fiber slurry 401. In another embodiment of the present invention, about 50 to about 100% by weight of the water non-dispersible polymer microfiber contained in the cut multi-component fiber slurry 201 can be added to the open microfiber slurry 401. Suspended as a non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber. In other embodiments, about 75 to about 100 weight percent, about 90 to about 100 weight percent, or about 95 to about 100 weight percent of the water non-dispersible polymer microfiber contained in the cut multicomponent fiber stream 201 Is suspended in the open microfiber slurry 401 as a water non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber.

The diameter or denier of the starting cut multicomponent fibers in stream 201 affects the degree to which water-dispersible sulfopolyester is separated from the multicomponent fibers in fiber open zone 400. Typical multicomponent fiber types generally have diameters ranging from about 12 microns to about 20 microns. Useful multicomponent fibers can have a larger starting diameter of about 40 microns or larger in diameter size. The time required to separate the desired amount of water dispersible sulfopolyester from the cut multicomponent fiber increases as the diameter of the cut multicomponent fiber in stream 201 increases.

The residence time, temperature and shear force in the fiber opening zone 400 also influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. Conditions affecting the opening process in the fiber opening zone 400 include residence time, slurry temperature and shear force, where the water temperature in the fiber opening zone 400, the range of residence time, and the degree of shear applied, are -Is dependent on the need to separate the water-dispersible sulfopolyester from the starting multicomponent fibers to a degree sufficient to allow the dispersible polymer microfibers to be separated and suspended in the continuous aqueous phase of the open microfiber slurry 401.

The residence time, temperature and shear force in the fiber opening zone 400 influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. The temperature of the fiber opening zone 400 may range from about 55 to about 100 ° C, from about 60 to about 90 ° C, or from about 65 to about 80 ° C. The residence time in the fiber opening zone 400 can range from about 5 minutes to about 10 seconds, from about 3 minutes to about 20 seconds, or from about 2 minutes to about 30 seconds. Sufficient mixing is maintained in the fiber open zone 400, so that the suspension of the cut water non-dispersible polymer microfibers is maintained such that settling of the cut microfibers is minimal. In another embodiment of the present invention, the mass per unit time of the cut water non-dispersible polymer microfibers in the fiber opening zone 400 is the mass per unit time of the water non-dispersible polymer microfibers entering the zone 400. Less than about 5%, less than about 3% of the mass per unit time of the number of non-dispersible polymer microfibers entering the zone 400, or of the number of non-dispersible polymer microfibers entering the zone 400 Less than about 1% of the mass per unit time.

Fiber opening in the fiber opening zone 400 can be achieved in any device that can allow for an acceptable residence time, temperature and mixing range. Examples of suitable devices include, but are not limited to, a stirred batch tank as shown in FIGS. 6B and 6C, a continuous stirred tank reactor, and a flow sufficient to minimize solid settling from the slurry as shown in FIG. 6A. Pipes are included. One example of a unit operation to achieve fiber opening in fiber opening zone 400 is a plug flow reactor, where heated multicomponent fiber slurry 301 is a zone 400 plug flow device, typically circular. It is sent by pipe or conduit. The residence time of the material in the plug flow device is calculated by dividing the filled volume in the device by the volume flow rate in the device. Material velocity within the device is defined as the cross-sectional area of the flow channel divided by the volumetric flow of liquid through the device.

In another embodiment of the invention, the fiber opening zone 400 may have a material flow rate in the pipe ranging from 0.1 to about 20 ft / sec, 0.2 to about 10 ft / sec, or about 0.5 to about 5 ft / sec. It may include pipes or conduits. For the flow of fluid or slurry in a pipe or conduit, the Reynolds number is a dimensionless number useful for describing the turbulence or motion of a fluid vortex that is irregular for both direction and time. For flow in a pipe or tube, the Reynolds number is generally defined as follows:

In the above formula,

D _H Is the hydraulic diameter (L) of the pipe (in meters);

Q is the volumetric flow rate (m ³ / s),

A is the pipe cross-sectional area (m ² ),

υ is the average velocity of the object relative to the fluid (SI unit: m / s),

μ is the dynamic viscosity of the fluid (Pa · s or N · s / m ² or kg / (m · s)),

v is the dynamic viscosity (v = μ / ρ) (m ² / s),

ρ is the density of the fluid (kg / m ³ ).

For flows in pipes of diameter D , experimental observations show that for fully developed flows, laminar flow occurs when Re _D is less than 2000 and turbulent flow when Re _D is greater than 4000. Between 2300 and 4000, layered and turbulent flows are possible ("transition" flows) depending on other factors, such as pipe roughness and flow uniformity.

The fiber open zone 400 may include pipes or conduits to facilitate the opening process, and the Reynolds number of flows through the pipes or conduits in the fiber open zone 400 ranges from about 2,100 to about 6,000, about 3,000 To about 6,000, or about 3,500 to about 6,000. In other embodiments, the fiber opening zone 400 can include a pipe or conduit to facilitate the opening process, wherein the Reynolds number of flows through the pipe or conduit is greater than 2,500, greater than about 3,500 or greater than about 4,000 to be.

The fiber opening zone 400 includes a pipe or conduit with a mixing device inserted in the pipe or conduit. The device may include an in-line mixing device. The in-line mixing device can be a static mixer without moving parts. In another embodiment, the in-line mixing device includes a movable portion. Non-limiting, such elements are mechanical devices for the purpose of imparting more mixed energy to the heated multicomponent fiber slurry 301, not achieved by flow through the pipe. The device can be inserted at the beginning of a pipe section used as a fiber opening zone, at the end of the pipe section, or at any location within the pipe flow path.

An open fiber slurry stream 401 comprising water non-dispersible polymer microfibers, water and water dispersible sulfopolyester is sent to a first solid-liquid separation zone 500, to provide a microfiber and a first mother liquor stream 501. A microfiber product stream 503 can be produced. In one embodiment, the first mother liquor stream 501 comprises water and water dispersible sulfopolyester.

The weight percent of solids in the open fiber slurry stream 401 can range from about 0.1 to about 20 weight percent, about 0.3 to about 10 weight percent, about 0.3 to about 5 weight percent, or about 0.3 to about 2.5 weight percent .

 The weight percent of solids in the microfiber product stream 503 can range from about 10 to about 65 weight percent, from about 15 to about 50 weight percent, from about 25 to about 45 weight percent, or from about 30 to about 40 weight percent.

Separating the microfiber product stream 503 from the open fiber slurry stream 401 can be accomplished by any method known in the art. In one embodiment, a wash stream 103 comprising water is sent to a first solid-liquid separation zone 500. The wash stream 103 can be used to wash the microfiber product stream in filter cloth media in the first solid-liquid separation zone 500 and / or the first solid-liquid separation zone 500 to produce a wash liquor stream 502. Fractions up to 100% by weight of the liquor stream 502 can be combined with the open fiber slurry stream 401 before entering the first solid-liquid separation zone 500. Fractions up to 100% by weight of the liquor stream 502 may be sent to a second solid-liquid separation zone 600. The liquor stream 502 may contain microfibers. In one embodiment, the g of microfiber mass passing through a filter medium having an opening of 200 microns or less in the first solid-liquid separation zone 500 ranges from about 1 to 2 g per cm ² of filter area. In other embodiments of the invention, the filter opening of the filter media in the first solid-liquid separation zone 500 may range from about 43 microns to 3000 microns, about 100 microns to 2000 microns, or about 500 microns to 2000 microns.

Separating the microfiber product stream from the microfiber slurry opened in the first solid-liquid separation zone 500 can be accomplished by one or several solid-liquid separation devices. Separation in the first solid-liquid separation zone 500 can be achieved by a batch and / or solid-liquid separation device or devices operated in a continuous manner. Suitable solid-liquid separation devices in the first solid-liquid separation zone 500 may include, but are not limited to, one of the following: perforated basket centrifuge, continuous vacuum belt filter, batch vacuum nutschfilter, batch perforated Settling tank, twin wire dewatering device, continuous horizontal belt filter with compression area, non-vibration inclined screen device with wedge wire filter media, continuous vacuum drum filter, dewatering conveyor belt, etc.

In one embodiment, the first solid-liquid separation zone 500 includes a twin wire dewatering device, wherein an open fiber slurry stream 401 is sent to the tapering gap between a pair of moving filter cloths moving in the same direction. . In the first zone of the twin wire dewatering device, water is drained due to gravity from the open fiber slurry stream 401 and from every narrow gap between the two moving filter cloths. In the downstream zone of the twin wire dewatering device, two filter cloths and a microfiber material between the two filter cloths are compressed more than once to mechanically reduce moisture in the microfiber material. In one embodiment, mechanical dewatering is accomplished by passing the two filter cloths and the contained microfiber material through a set of one or more rollers that exert a compressive force on the two filter cloths and the microfiber material between them. In another embodiment, mechanical dewatering is achieved by passing the two filter cloths and microfiber material through one or more sets of pressure rollers.

In another embodiment of the invention, the force exerted by mechanical dewatering for each set of pressure rollers ranges from about 25 to about 300 lbs per linear inch of filter media width, from about 50 to about 200 per linear inch of filter media width. in the lb range, or from about 70 to about 125 lb per linear inch of filter media width. The microfiber product stream 503 is discharged from the twin wire dewatering apparatus as the two filter cloths are separated and split in the solid discharge zone of the twin wire dewatering apparatus. The thickness of the microfiber material discharged may range from about 0.2 to about 1.5 inches, from about 0.3 to about 1.25 inches, or from about 0.4 to about 1 inch. In one embodiment, a stream of liquor comprising water is continuously applied to the filter medium. In another embodiment, a stream of liquor comprising water is periodically applied to the filter medium.

In another embodiment, the first solid-liquid separation zone 500 includes a belt filter device comprising a gravity drainage zone and a pressurized dehydration zone as illustrated in FIG. 7. The open microfiber slurry 401 is sent to a tapering gap between a pair of moving filter cloths moving in the same direction, first passing through the gravity drainage zone and then in a serpentine arrangement as shown in Figure 6B. It passes through the pressurized dehydration zone or press zone included. As the belt is fed through the rollers, water escapes from the solid. In this process, when the belt passes through the final pair of rollers, the filter cloth is separated and solid is discharged from the belt filter device.

In another embodiment of the present invention, at least a portion of the water contained in the first mother liquor stream 501 comprising water and water dispersible sulfopolyester is recovered and recycled. The first mother liquor stream 501 may be recycled to the first solid-liquid separation zone 500. Depending on the efficiency of the first solid-liquid separation zone in the removal of water non-dispersible polymer microfibers, the first mother liquor stream 501 may be a fiber open zone 400, or a heat exchanger zone before entering the zone 400. It can be recycled to (800). The first mother liquor stream 501 may contain a small amount of solids comprising water non-dispersible polymer microfibers due to penetration and cloth washing. In one embodiment, g of the water non-dispersible polymer microfiber material passing through the filter medium in the first solid separation zone having an opening of 2000 microns or less ranges from about 1 to about 2 g per cm ² of filter area. . Before sending the first mother liquor stream 501 to the first enrichment zone 700 and the heat exchange zone 800 (in these zones, a number of non-dispersible polymer microfiber solids with negative effects can be collected and accumulated). It is desirable to minimize the number of non-dispersible polymer microfibers in stream 501.

The second solid-liquid separation zone 600 removes at least a portion of the water non-dispersible polymer microfiber solids present in the first mother liquor stream 501 to thereby remove the second wet cake comprising the water non-dispersible microfibers. It can function to generate a stream 602 and a second mother liquor stream 601 comprising water and water dispersible sulfopolyester.

In one embodiment, the second mother liquor stream 601 is sent to the first enrichment zone 700 and / or heat exchanger zone 800, where the second mother liquor stream 601 is sent to the first enrichment zone 700. ) May be in the range of 0 to 100%, and the remainder of the stream is sent to the heat exchanger zone 800. The second mother liquor stream 601 can be recycled to the fiber open zone 400, or to the heat exchanger zone 800 before being sent to the zone 400. The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Any portion of the second mother liquor stream 601 sent to the first concentration zone is subjected to a separation process to produce a first recovered water stream 703 and a first polymer concentrate stream 702 rich in water dispersible sulfopolyester. Produced, wherein the weight percent of the water dispersible sulfopolyester in the first polymer concentrate stream 702 can range from about 5 to about 85 weight percent, from about 10 to about 65 weight percent, or from about 15 to about 45 weight percent. have. The first recovered water stream 703 can be recycled to the fiber slurry zone 200, the fiber opening zone 400, or the heat exchanger zone 800 before being sent to the zones 200 and / or 400. have. The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Water may be removed from the second mother liquor stream 601 in the first enrichment zone 700 by any method known in the art to produce a first polymer enrichment stream 702. In one embodiment, removal of water includes an evaporation process by boiling water in a batch or continuous evaporation apparatus. For example, one or more thin film evaporators can be used for this application.

In another embodiment, the first polymer concentrate stream 702 can be produced using membrane technology comprising nanofiltration media. In another embodiment, a process comprising an extraction device can be used to extract the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. A combination of evaporation, membrane, and extraction steps can be used to separate the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. The first polymer concentrate stream 702 can then be discharged out of the process.

In one embodiment, the first polymer concentrate stream 702 is sent to a second concentration zone 900, whereby the melted polymer stream 903 comprising water-dispersible sulfopolyester, wherein the weight percent of polymer is about 95 to about 100%) and steam stream 902 comprising water. In one embodiment, the stream 903 comprises water dispersible sulfopolyester. Suitable devices for the second concentration zone 900 include any device known in the art that can supply an aqueous dispersion of a water dispersible polymer and can produce a 95% to 100% water dispersible polymer stream 903. . This embodiment includes feeding an aqueous dispersion of the water-dispersible sulfopolyester polymer to the second concentration zone 900. The temperature of the feed stream is typically below 100 ° C.

In one embodiment, the second enrichment zone 900 is one or more devices characterized by a jacketed tubular shell containing a rotating transport screw, wherein the transport screw is heated with heat transfer fluid or steam Transport and high shear mixing elements). The jacket or shell is evacuated to allow steam to be removed. The shell jacket can be banded to allow different temperature set points along the length of the device. During continuous operation, the first polymer concentrate stream 702 includes water and water dispersible sulfopolyester, and is continuously fed to the second concentration zone 900. Within the device, there are at least three distinct and different forms of material in the steady state. The material in the device is first present as an aqueous dispersion of a water-dispersible sulfopolyester polymer. As the aqueous dispersion of sulfopolyester polymer moves through the device, water evaporates due to the heat of the jacket and the inner screw. When sufficient water is evaporated, the material becomes a second form comprising a viscous plug at a temperature lower than the melting point of the sulfopolyester polymer. The aqueous dispersion cannot flow past this viscous plug and is limited to the first aqueous dispersion zone of the device. Due to the heat of the jacket, the heat of the internally heated screw, and the heat due to the mixing shear force of this high-viscosity plug material, substantially all of the water present at this location is evaporated and the temperature is maintained until the melting temperature of the sulfoester is reached. Ascending, a third final physical form of the material comprising the molten sulfopolyester polymer is produced in the device. The molten sulfopolyester polymer is then exited the device through an extrusion die, typically cooled and cut into pellets in any manner known in the art. It should be understood that the device for the second enrichment zone 900 described above can also be operated in a batch mode, where the continuous of the viscous plug material and finally the sulfopolyester melt, starting with the aqueous dispersion throughout the length of the device. Three physical forms of the material described above occur in different time zones in sequence.

In one embodiment, the vapor generated in the second concentration zone 900 can be condensed and sent to the heat exchanger zone 800 and / or disposed of and / or sent to the wash stream 103. In another embodiment, condensed vapor stream 902 comprising water vapor can be sent to heat exchanger zone 800 to provide at least a portion of the energy required to generate the temperature required for stream 801. The molten polymer stream 903 comprising a water-dispersible polymer comprising sulfopolyester in the molten phase can be cooled and chopped into pellets by any method known in the art.

Impurities may be introduced into the process, and concentrated in water that is recovered and recycled. The concentration of impurities in the second mother liquor 601 and the first recovered water stream 701 may be adjusted to an acceptable level using one or more purge streams 603 and 701. In one embodiment, a portion of the second mother liquor stream 601 can be isolated and purged from the process. In one embodiment, a portion of the first recovered water stream 701 can be isolated and purged from the process.

In another embodiment of the present invention, a method for producing a microfiber product stream as shown in FIG. 3B is provided. This way

(A) contacting the short-cut multi-component fiber 101 having a length of less than 25 mm in a mixing zone with a heated aqueous stream 801 to produce a short-cut multi-component fiber slurry 301, wherein the The short-cut multicomponent fiber 101 comprises at least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester, wherein the heated aqueous stream is at least 40 ° C. Temperature, step;

(B) the short-cut multicomponent fiber slurry 301, and optionally, a heated aqueous stream 801 is sent to the fiber open zone 400 to remove a portion of the water dispersible sulfopolyester and thereby open microfibers Generating a slurry 401, wherein the open microfiber slurry 401 comprises water non-dispersible polymer microfibers, water dispersible sulfopolyester and water; And

(C) sending the opened microfiber slurry 401 to a first solid-liquid separation zone 500 to generate a microfiber product stream 503 and a first mother liquor stream 501, wherein the first mother liquor Stream 501 comprises water and water dispersible sulfopolyester

It includes.

In this embodiment of the present invention as shown in Figure 3B, the fiber slurry zone 200 and the fiber mixing zone 300 are combined in one unit operation in the open process zone 1100. The open process zone 1100 includes a mixing zone 200 and a fiber opening zone 400.

The processed aqueous stream 103 for use in this method can be generated by sending the aqueous stream 102 to the aqueous processing band 1000 to generate a processed aqueous stream 103. The aqueous stream contains water. In embodiments of the present invention, the monovalent metal cation in the treated aqueous stream 103 can be less than about 1000 ppm by weight, less than about 500 ppm by weight, less than about 100 ppm by weight, or less than about 50 ppm by weight. Removal of divalent and polyvalent metal cations from aqueous stream 102 is one function of aqueous treatment zone 1000. In other embodiments of the invention, the concentration of the divalent and polyvalent metal cations is less than about 50 ppm by weight, less than about 25 ppm by weight, less than about 10 ppm by weight, or less than about 5 ppm by weight. The temperature of the stream 103 may range from groundwater temperature to about 40 ° C.

Treatment of the aqueous stream 102 in the aqueous treatment zone 1000 can be accomplished by any method known in the art. In one embodiment, the aqueous treatment zone 1000 includes distillation equipment to generate and condense water vapor to produce a treated aqueous stream 103. In another embodiment, water can be sent to a reverse osmosis membrane separation zone to remove monovalent and divalent metal cations from the water to produce a treated aqueous stream 103. In another embodiment, water is sent to the ion exchange resin, producing a treated aqueous stream 103 with metal concentrations of an acceptable low concentration. In another embodiment, the water is sent to a commercial water softening device to produce a treated aqueous stream 103 with acceptable concentrations of divalent and polyvalent metal ions. It should be understood that any combination of these water treatment options is used to achieve the required treatment water characteristics.

The treated aqueous stream 103 can be sent to any required location in the process. In one embodiment, a portion of stream 103 is sent to first solid-liquid separation zone 500 to act as a wash liquor for the solids contained in cloth wash liquor and / or first solid-liquid separation zone 500. .

In one embodiment, at least a portion of the treated aqueous stream 103 is sent to a heat exchanger zone 800. In another embodiment, at least a portion of the treated aqueous stream 103 is sent to a mixing zone 300. In another embodiment, at least a portion of the treated aqueous stream 103 is sent to a heat exchanger zone 800 and at least a portion of the treated aqueous stream 103 is sent to a mixing zone 300. One function of the heat exchanger zone 800 is to produce a heated aqueous stream 801 at a specific controlled temperature.

In one embodiment, the streams that can be fed to the heat exchanger zone 800 are treated aqueous stream 103 and second mother liquor stream 601. In another embodiment, stream 800 that can be fed to heat exchanger zone 800 comprises treated aqueous stream 103, first recovered water stream 703, first mother liquor stream 501, and 2 The mother liquor stream 601 is included.

Any device known in the art for controlling the temperature of stream 801, such as, but not limited to, any heat exchanger using a stream used to provide some of the energy required, to provide some of the energy required Any heat exchanger using the heat transfer fluid used, any heat exchanger using an electrical heating element used to provide some of the required energy, and water condensed and the condensate supplied to the heat exchanger zone 800. Any container or tank that uses direct steam injection to be mixed can be used. The multicomponent fiber stream 90 is sent to a fiber cutting zone 100 to produce a cut multicomponent fiber stream 101. The multicomponent fiber can have any multicomponent structure known in the art. Multicomponent fibers include water dispersible sulfopolyesters and water non-dispersible polymers, as described herein above.

The multicomponent fiber stream 90 can be cut using any device known in the art to produce a cut multicomponent fiber stream 101. In one embodiment, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 50 mm. In other embodiments, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 25 mm, less than about 20 mm, less than about 15 mm, less than about 10 mm, less than about 5 mm, or about 2.5 mm. Less than.

A portion of the cut multi-component fiber stream 101 and a heated treated aqueous stream 801 is sent to a mixing zone 300 to produce a heated multi-component fiber slurry 301 comprising water and cut multi-component fibers. To create.

The temperature of the heated multicomponent fiber slurry 301 is to separate the number non-dispersible polymer portion of the cut multicomponent fiber from the number non-dispersible polymer portion of the cut multicomponent fiber in the fiber open region 400. affect. In other embodiments of the invention, the temperature of the heated multicomponent fiber slurry 301 may range from about 55 to about 100 ° C, from about 60 to about 90 ° C, or from about 65 to about 80 ° C.

The weight percentage of the cut microfibers in the heated multicomponent fiber slurry 301 can be controlled. In other embodiments, the weight percent of the cut microfibers in the heated multicomponent fiber slurry 301 is from about 10 weight percent to about 0.1 weight percent, from about 5 weight percent to about 0.2 weight percent, from about 3 weight percent to about 0.3 weight percent %, Or about 2% to about 0.4% by weight.

Any device known in the art that can mix the heated aqueous stream 801 with the cut multicomponent fiber 101 can be used in the mixing zone 300. Suitable devices include both continuous and batch mixing devices. In one embodiment, a mixing device suitable for mixing zone 300 includes a tank and a stirrer. In another embodiment, suitable mixing devices include pipes or conduits.

In another embodiment, a mixing device suitable for mixing zone 300 is a pipe or conduit having a diameter such that the velocity in the conduit is sufficient to mix the cut multicomponent fiber slurry 201 and the heated aqueous stream 801. In this case, less than about 2% by weight, less than about 1% by weight, or less than about 0.5% by weight of the cut multi-component material introduced per minute into the conduit is precipitated and accumulated in the conduit.

Subsequently, the heated multicomponent fiber slurry 301 can be sent to the fiber open zone 400. One function of the fiber opening zone 400 is to separate the water-dispersible polymer from the cut multi-component fibers so that at least a portion of the water non-dispersible polymer microfibers are separated from the cut multi-component fiber fibers and opened micro It is to be suspended in the fiber slurry 401. In another embodiment of the present invention, about 50 to about 100% by weight of the water non-dispersible polymer microfiber contained in the cut multi-component fiber slurry 201 can be added to the open microfiber slurry 401. Suspended as a non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber. In other embodiments, about 75 to about 100 weight percent, about 90 to about 100 weight percent, or about 95 to about 100 weight percent of the water non-dispersible polymer microfiber contained in the cut multicomponent fiber stream 201 Is suspended in the open microfiber slurry 401 as a water non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber.

The diameter or denier of the starting cut multicomponent fibers in stream 201 affects the degree to which water-dispersible sulfopolyester is separated from the multicomponent fibers in fiber open zone 400. Typical multicomponent fiber types generally have diameters ranging from about 12 microns to about 20 microns. Useful multicomponent fibers can have a larger starting diameter of about 40 microns or larger in diameter size. The time required to separate the desired amount of water dispersible sulfopolyester from the cut multicomponent fiber increases as the diameter of the cut multicomponent fiber in stream 201 increases.

The residence time, temperature and shear force in the fiber opening zone 400 also influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. Conditions affecting the opening process in the fiber opening zone 400 include residence time, temperature, and shear force, where the water temperature in the fiber opening zone 400, the range of residence time, and the degree of shear applied, are non- It is governed by the need to separate the water-dispersible sulfopolyester from the starting multicomponent fibers to a degree sufficient to allow the dispersible polymer microfibers to be separated and suspended in the continuous aqueous phase of the open microfiber slurry 401.

The residence time, temperature and shear force in the fiber opening zone 400 influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. The temperature of the fiber opening zone 400 may range from about 55 to about 100 ° C, from about 60 to about 90 ° C, or from about 65 to about 80 ° C. The residence time in the fiber opening zone 400 can range from about 5 minutes to about 10 seconds, from about 3 minutes to about 20 seconds, or from about 2 minutes to about 30 seconds. Sufficient mixing is maintained in the fiber open zone 400, so that the suspension of the cut water non-dispersible polymer microfibers is maintained such that settling of the cut microfibers is minimal. In another embodiment of the present invention, the mass per unit time of the cut water non-dispersible polymer microfibers in the fiber opening zone 400 is the mass per unit time of the water non-dispersible polymer microfibers entering the zone 400. Less than about 5%, less than about 3% of the mass per unit time of the number of non-dispersible polymer microfibers entering the zone 400, or of the number of non-dispersible polymer microfibers entering the zone 400 Less than about 1% of the mass per unit time.

Fiber opening in the fiber opening zone 400 can be achieved in any device that can allow for an acceptable residence time, temperature and mixing range. Examples of suitable devices include, but are not limited to, a stirred batch tank as shown in FIGS. 6B and 6C, a continuous stirred tank reactor, and a flow sufficient to minimize solid settling from the slurry as shown in FIG. 6A. Pipes are included. One example of a unit operation to achieve fiber opening in fiber opening zone 400 is a plug flow reactor, where heated multicomponent fiber slurry 301 is a zone 400 plug flow device, typically circular. It is sent by pipe or conduit. The residence time of the material in the plug flow device is calculated by dividing the filled volume in the device by the volume flow rate in the device. Material velocity within the device is defined as the cross-sectional area of the flow channel divided by the volumetric flow of liquid through the device.

In another embodiment of the invention, the fiber opening zone 400 may have a material flow rate in the pipe ranging from 0.1 to about 20 ft / sec, 0.2 to about 10 ft / sec, or about 0.5 to about 5 ft / sec. It may include pipes or conduits. For the flow of fluid or slurry in a pipe or conduit, the Reynolds number is a dimensionless number useful for describing the turbulence or motion of a fluid vortex that is irregular for both direction and time. For flow in a pipe or tube, the Reynolds number is generally defined as follows:

In the above formula,

D _H Is the hydraulic diameter (L) of the pipe (in meters);

Q is the volumetric flow rate (m ³ / s),

A is the pipe cross-sectional area (m ² ),

υ is the average velocity of the object relative to the fluid (SI unit: m / s),

μ is the dynamic viscosity of the fluid (Pa · s or N · s / m ² or kg / (m · s)),

v is the dynamic viscosity (v = μ / ρ) (m ² / s),

ρ is the density of the fluid (kg / m ³ ).

For flows in pipes of diameter D , experimental observations show that for fully developed flows, laminar flow occurs when Re _D is less than 2000 and turbulent flow when Re _D is greater than 4000. Between 2300 and 4000, layered and turbulent flows are possible ("transition" flows) depending on other factors, such as pipe roughness and flow uniformity.

The fiber open zone 400 may include pipes or conduits to facilitate the opening process, and the Reynolds number of flows through the pipes or conduits in the fiber open zone 400 ranges from about 2,100 to about 6,000, about 3,000 To about 6,000, or about 3,500 to about 6,000. In other embodiments, the fiber opening zone 400 can include a pipe or conduit to facilitate the opening process, wherein the Reynolds number of flows through the pipe or conduit is greater than 2,500, greater than about 3,500 or greater than about 4,000 to be.

The fiber opening zone 400 includes a pipe or conduit with a mixing device inserted in the pipe or conduit. The device may include an in-line mixing device. The in-line mixing device can be a static mixer without moving parts. In another embodiment, the in-line mixing device includes a movable portion. Non-limiting, such elements are mechanical devices for the purpose of imparting more mixed energy to the heated multicomponent fiber slurry 301, not achieved by flow through the pipe. The device can be inserted at the beginning of a pipe section used as a fiber opening zone, at the end of the pipe section, or at any location within the pipe flow path.

An open fiber slurry stream 401 comprising water non-dispersible polymer microfibers, water and water dispersible sulfopolyester is sent to a first solid-liquid separation zone 500, to provide a microfiber and a first mother liquor stream 501. A microfiber product stream 503 can be produced. In one embodiment, the first mother liquor stream 501 comprises water and water dispersible sulfopolyester.

The weight percent of solids in the open fiber slurry stream 401 can range from about 0.1 to about 20 weight percent, about 0.3 to about 10 weight percent, about 0.3 to about 5 weight percent, or about 0.3 to about 2.5 weight percent .

 The weight percent of solids in the microfiber product stream 503 can range from about 10 to about 65 weight percent, from about 15 to about 50 weight percent, from about 25 to about 45 weight percent, or from about 30 to about 40 weight percent.

Separating the microfiber product stream 503 from the open fiber slurry stream 401 can be accomplished by any method known in the art. In one embodiment, a wash stream 103 comprising water is sent to a first solid-liquid separation zone 500. The wash stream 103 can be used to wash the microfiber product stream in filter cloth media in the first solid-liquid separation zone 500 and / or the first solid-liquid separation zone 500 to produce a wash liquor stream 502. Fractions up to 100% by weight of the liquor stream 502 can be combined with the open fiber slurry stream 401 before entering the first solid-liquid separation zone 500. Fractions up to 100% by weight of the liquor stream 502 may be sent to a second solid-liquid separation zone 600. The liquor stream 502 may contain microfibers. In one embodiment, the g of microfiber mass passing through a filter medium having an opening of 200 microns or less in the first solid-liquid separation zone 500 ranges from about 1 to 2 g per cm ² of filter area. In other embodiments of the invention, the filter opening of the filter media in the first solid-liquid separation zone 500 may range from about 43 microns to 3000 microns, about 100 microns to 2000 microns, or about 500 microns to 2000 microns.

Separating the microfiber product stream from the microfiber slurry opened in the first solid-liquid separation zone 500 can be accomplished by one or several solid-liquid separation devices. Separation in the first solid-liquid separation zone 500 can be achieved by a batch and / or solid-liquid separation device or devices operated in a continuous manner. Suitable solid-liquid separation devices in the first solid-liquid separation zone 500 may include, but are not limited to, one of the following: perforated basket centrifuge, continuous vacuum belt filter, batch vacuum nutschfilter, batch perforated Settling tank, twin wire dewatering device, continuous horizontal belt filter with compression area, non-vibration inclined screen device with wedge wire filter media, continuous vacuum drum filter, dewatering conveyor belt, etc.

In one embodiment, the first solid-liquid separation zone 500 includes a twin wire dewatering device, wherein an open fiber slurry stream 401 is sent to the tapering gap between a pair of moving filter cloths moving in the same direction. . In the first zone of the twin wire dewatering device, water is drained due to gravity from the open fiber slurry stream 401 and from every narrow gap between the two moving filter cloths. In the downstream zone of the twin wire dewatering device, two filter cloths and a microfiber material between the two filter cloths are compressed more than once to mechanically reduce moisture in the microfiber material. In one embodiment, mechanical dewatering is accomplished by passing the two filter cloths and the contained microfiber material through a set of one or more rollers that exert a compressive force on the two filter cloths and the microfiber material between them. In another embodiment, mechanical dewatering is accomplished by passing the two filter cloths and microfiber materials through one or more sets of pressure rollers and a fixed surface.

In another embodiment of the invention, the force exerted by mechanical dehydration ranges from about 25 to about 300 lb per linear inch of filter media width, from about 50 to about 200 lb per linear inch of filter media width, or filter media It may range from about 70 to about 125 lbs per linear inch of width. The microfiber product stream 503 is discharged from the twin wire dewatering apparatus as the two filter cloths are separated and split in the solid discharge zone of the twin wire dewatering apparatus. The thickness of the microfiber material discharged may range from about 0.2 to about 1.5 inches, from about 0.3 to about 1.25 inches, or from about 0.4 to about 1 inch. In one embodiment, a stream of liquor comprising water is continuously applied to the filter medium. In another embodiment, a stream of liquor comprising water is periodically applied to the filter medium.

In another embodiment, the first solid-liquid separation zone 500 includes a belt filter device comprising a gravity drainage zone and a pressurized dehydration zone as illustrated in FIG. 7. The open microfiber slurry 401 is sent to a tapering gap between a pair of moving filter cloths moving in the same direction, which first passes through the gravity drainage zone and then in a serpentine arrangement as shown in Figure 6B. It passes through the pressurized dehydration zone or press zone included. As the belt is fed through the rollers, water escapes from the solid. In this process, when the belt passes through the final pair of rollers, the filter cloth is separated and solid is discharged from the belt filter device.

In another embodiment of the present invention, at least a portion of the water contained in the first mother liquor stream 501 comprising water and water dispersible sulfopolyester is recovered and recycled. The first mother liquor stream 501 may be recycled to the first solid-liquid separation zone 500. Depending on the efficiency of the first solid-liquid separation zone in the removal of water non-dispersible polymer microfibers, the first mother liquor stream 501 comprises a fiber slurry zone 200, a mixing zone 300, and a fiber opening zone 400. Alternatively, it may be recycled to the heat exchanger zone 800 before entering the zones 200, 300 and / or 400. The first mother liquor stream 501 may contain a small amount of solids comprising water non-dispersible polymer microfibers due to penetration and cloth washing. In one embodiment, g of the water non-dispersible polymer microfiber material passing through the filter medium in the first solid separation zone having an opening of 2000 microns or less ranges from about 1 to about 2 g per cm ² of filter area. . Before sending the first mother liquor stream 501 to the first enrichment zone 700 and the heat exchange zone 800 (in these zones, a number of non-dispersible polymer microfiber solids with negative effects can be collected and accumulated). It is desirable to minimize the number of non-dispersible polymer microfibers in stream 501.

The second solid-liquid separation zone 600 removes at least a portion of the water non-dispersible polymer microfiber solids present in the first mother liquor stream 501 to thereby remove the second wet cake comprising the water non-dispersible microfibers. It can function to generate a stream 602 and a second mother liquor stream 601 comprising water and water dispersible sulfopolyester.

In one embodiment, the second mother liquor stream 601 is sent to the first enrichment zone 700 and / or heat exchanger zone 800, where the second mother liquor stream 601 is sent to the first enrichment zone 700. ) May be in the range of 0 to 100%, and the remainder of the stream is sent to the heat exchanger zone 800. The second mother liquor stream 601 is a heat exchanger before entering the fiber slurry zone 200, the mixing zone 300, the fiber opening zone 400, or the zones 200, 300 and / or 400. It can be recycled to the band 800. The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Any portion of the second mother liquor stream 601 sent to the first concentration zone is subjected to a separation process to produce a first recovered water stream 703 and a first polymer concentrate stream 702 rich in water dispersible sulfopolyester. Produced, wherein the weight percent of the water dispersible sulfopolyester in the first polymer concentrate stream 702 can range from about 5 to about 85 weight percent, from about 10 to about 65 weight percent, or from about 15 to about 45 weight percent. have. The first recovered water stream 703 is before entering the fiber slurry zone 200, the mixing zone 300, the fiber opening zone 400, or the zones 200, 300 and / or 400. It can be recycled to the heat exchanger zone (800). The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Water may be removed from the second mother liquor stream 601 in the first enrichment zone 700 by any method known in the art to produce a first polymer enrichment stream 702. In one embodiment, removal of water includes an evaporation process by boiling water in a batch or continuous evaporation apparatus. For example, one or more thin film evaporators can be used for this application. In another embodiment, the first polymer concentrate stream 702 can be produced using membrane technology comprising nanofiltration media. In another embodiment, a process comprising an extraction device can be used to extract the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. A combination of evaporation, membrane, and extraction steps can be used to separate the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. The first polymer concentrate stream 702 can then be discharged out of the process.

In one embodiment, the first polymer concentrate stream 702 is sent to a second concentration zone 900, whereby the melted polymer stream 903 comprising water-dispersible sulfopolyester, wherein the weight percent of polymer is about 95 to about 100%) and steam stream 902 comprising water. In one embodiment, the stream 903 comprises water dispersible sulfopolyester. Suitable devices for the second concentration zone 900 include any device known in the art that can supply an aqueous dispersion of a water dispersible polymer and can produce a 95% to 100% water dispersible polymer stream 903. . This embodiment includes feeding an aqueous dispersion of the water-dispersible sulfopolyester polymer to the second concentration zone 900. The temperature of the feed stream is typically below 100 ° C.

In one embodiment, the second enrichment zone 900 is one or more devices characterized by a jacketed tubular shell containing a rotating transport screw, wherein the transport screw is heated with heat transfer fluid or steam Transport and high shear mixing elements). The jacket or shell is evacuated to allow steam to be removed. The shell jacket can be banded to allow different temperature set points along the length of the device. During continuous operation, the first polymer concentrate stream 702 includes water and water dispersible sulfopolyester, and is continuously fed to the second concentration zone 900. Within the device, there are at least three distinct and different forms of material in the steady state. The material in the device is first present as an aqueous dispersion of a water-dispersible sulfopolyester polymer. As the aqueous dispersion of sulfopolyester polymer moves through the device, water evaporates due to the heat of the jacket and the inner screw. When sufficient water is evaporated, the material becomes a second form comprising a viscous plug at a temperature lower than the melting point of the sulfopolyester polymer. The aqueous dispersion cannot flow past this viscous plug and is limited to the first aqueous dispersion zone of the device. Due to the heat of the jacket, the heat of the internally heated screw, and the heat due to the mixing shear force of this high-viscosity plug material, substantially all of the water present at this location is evaporated and the temperature is maintained until the melting temperature of the sulfoester is reached. Ascending, a third final physical form of the material comprising the molten sulfopolyester polymer is produced in the device. The molten sulfopolyester polymer is then exited the device through an extrusion die, typically cooled and cut into pellets in any manner known in the art. It should be understood that the device for the second enrichment zone 900 described above can also be operated in a batch mode, where the continuous of the viscous plug material and finally the sulfopolyester melt, starting with the aqueous dispersion throughout the length of the device. Three physical forms of the material described above occur in different time zones in sequence.

In one embodiment, the vapor generated in the second concentration zone 900 can be condensed and sent to the heat exchanger zone 800 and / or disposed of and / or sent to the wash stream 103. In another embodiment, condensed vapor stream 902 comprising water vapor can be sent to heat exchanger zone 800 to provide at least a portion of the energy required to generate the temperature required for stream 801. The molten polymer stream 903 comprising a water-dispersible polymer comprising sulfopolyester in the molten phase can be cooled and chopped into pellets by any method known in the art.

Impurities may be introduced into the process, and concentrated in water that is recovered and recycled. The concentration of impurities in the second mother liquor 601 and the first recovered water stream 701 may be adjusted to an acceptable level using one or more purge streams 603 and 701. In one embodiment, a portion of the second mother liquor stream 601 can be isolated and purged from the process. In one embodiment, a portion of the first recovered water stream 701 can be isolated and purged from the process.

In another embodiment of the present invention, another method of producing a microfiber product stream is provided, as shown in FIG. 4. This way

(A) contacting the short-cut multi-component fiber 101 having a length of less than 25 mm with the aqueous stream 103 treated in the fiber slurry zone 200 to produce a short-cut multi-component fiber slurry 201. Wherein, the short-cut multicomponent fiber 101 comprises at least one water dispersible sulfopolyester and at least one water non-dispersible synthetic polymer that is immiscible with the water dispersible sulfopolyester, and the treated aqueous stream Is a temperature of 40 ° C. or higher;

(B) contacting the short-cut multi-component fiber slurry 201 with a heated aqueous stream 801 in a mixing zone 300 to produce a heated multi-component fiber slurry 301;

(C) sending the heated multi-component fiber slurry 301 to the fiber opening zone 400 to remove a portion of the water-dispersible sulfopolyester to produce an open microfiber slurry 401; And

(D) sending the open microfiber slurry 401 to a first solid-liquid separation zone 500 to generate a microfiber product stream 503 and a first mother liquor stream 501, wherein the first mother liquor Stream 501 comprises water and water dispersible sulfopolyester

It includes.

In this embodiment of the present invention as shown in Figure 4, the open process zone 1100 includes a fiber slurry zone 200, a mixing zone 300 and a fiber opening zone 400.

The processed aqueous stream 103 for use in this method can be generated by sending the aqueous stream 102 to the aqueous processing band 1000 to generate a processed aqueous stream 103. The aqueous stream contains water. In embodiments of the present invention, the monovalent metal cation in the treated aqueous stream 103 can be less than about 1000 ppm by weight, less than about 500 ppm by weight, less than about 100 ppm by weight, or less than about 50 ppm by weight. Removal of divalent and polyvalent metal cations from aqueous stream 102 is one function of aqueous treatment zone 1000. In other embodiments of the invention, the concentration of the divalent and polyvalent metal cations is less than about 50 ppm by weight, less than about 25 ppm by weight, less than about 10 ppm by weight, or less than about 5 ppm by weight. The temperature of the stream 103 may range from groundwater temperature to about 40 ° C.

Treatment of the aqueous stream 102 in the aqueous treatment zone 1000 can be accomplished by any method known in the art. In one embodiment, the aqueous treatment zone 1000 includes distillation equipment to generate and condense water vapor to produce a treated aqueous stream 103. In another embodiment, water can be sent to a reverse osmosis membrane separation zone to remove monovalent and divalent metal cations from the water to produce a treated aqueous stream 103. In another embodiment, water is sent to the ion exchange resin, producing a treated aqueous stream 103 with metal concentrations of an acceptable low concentration. In another embodiment, the water is sent to a commercial water softening device to produce a treated aqueous stream 103 with acceptable concentrations of divalent and polyvalent metal ions. It should be understood that any combination of these water treatment options is used to achieve the required treatment water characteristics.

The treated aqueous stream 103 can be sent to any required location in the process. In one embodiment, a portion of stream 103 is sent to first solid-liquid separation zone 500 to act as a wash liquor for the solids contained in cloth wash liquor and / or first solid-liquid separation zone 500. .

In one embodiment, at least a portion of the treated aqueous stream 103 is sent to a heat exchanger zone 800. In another embodiment, at least a portion of the treated aqueous stream 103 is sent to a fiber slurry zone 200. In another embodiment, at least a portion of the treated aqueous stream 103 is sent to a heat exchanger zone 800 and at least a portion of the treated aqueous stream 103 is sent to a fiber slurry zone 200. One function of the heat exchanger zone 800 is to produce a heated aqueous stream 801 at a specific controlled temperature.

In one embodiment, the streams that can be fed to the heat exchanger zone 800 are treated aqueous stream 103 and second mother liquor stream 601. In another embodiment, the streams that can be fed to the heat exchanger zone 800 are treated aqueous stream 103, first recovered water stream 703, first mother liquor stream 501 and second mother liquor stream 601.

Any device known in the art for controlling the temperature of stream 801, such as, but not limited to, any heat exchanger using a stream used to provide some of the energy required, to provide some of the energy required Any heat exchanger using the heat transfer fluid used, any heat exchanger using an electrical heating element used to provide some of the required energy, and water condensed and the condensate supplied to the heat exchanger zone 800. Any container or tank that uses direct steam injection to be mixed can be used.

The multicomponent fiber stream 90 is sent to a fiber cutting zone 100 to produce a cut multicomponent fiber stream 101. The multicomponent fiber can have any multicomponent structure known in the art. Multicomponent fibers include water dispersible sulfopolyesters and water non-dispersible polymers, as described herein above.

The multicomponent fiber stream 90 can be cut using any device known in the art to produce a cut multicomponent fiber stream 101. In one embodiment, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 50 mm. In other embodiments, the length of the cut fibers in the cut multicomponent fiber stream 101 is less than about 25 mm, less than about 20 mm, less than about 15 mm, less than about 10 mm, less than about 5 mm, or about 2.5 mm. Less than.

A portion of the cut multi-component fiber stream 101 and a heated treated aqueous stream 801 is sent to a fiber slurry zone 200 to cut a multi-component fiber slurry 201 comprising water and cut multi-component fibers. Produces In one embodiment, the weight percent of the cut microfibers in the cut multicomponent fiber slurry 201 is from about 35 weight percent to about 1 weight percent, from about 25 weight percent to about 1 weight percent, from about 15 weight percent to about 15 weight percent 1% by weight, or from about 7% to about 1% by weight.

The temperature of the cut multicomponent fiber slurry 201 may range from about 5 to about 45 ° C, from about 10 to about 35 ° C, or from about 10 to about 25 ° C. In one embodiment, the fiber slurry zone 200 includes a tank with sufficient agitation to produce a suspension in a continuous aqueous phase of cut multicomponent fibers.

Any device known in the art to be suitable for mixing solids with water and maintaining the suspension in the resulting aqueous phase of the resulting cut multicomponent fiber can be used in the fiber slurry zone 200. The fiber slurry zone 200 can include a batch or continuous mixing device operated in a continuous or batch mode. Suitable devices for use in the fiber slurry zone 200 include, but are not limited to, a hydro-pulping machine, a continuously stirred tank reactor, and a tank with agitation operated in a batch mode.

The cut multi-component fiber slurry 201 and heated aqueous stream 801 are then sent to a mixing zone 300 to combine to produce a heated multi-component fiber slurry 301. The temperature of the heated multicomponent fiber slurry 301 is to separate the number non-dispersible polymer portion of the cut multicomponent fiber from the number non-dispersible polymer portion of the cut multicomponent fiber in the fiber open region 400. affect. In other embodiments of the invention, the temperature of the heated multicomponent fiber slurry 301 may range from about 55 to about 100 ° C, from about 60 to about 90 ° C, or from about 65 to about 80 ° C.

The weight percentage of the cut microfibers in the heated multicomponent fiber slurry 301 can be controlled. In other embodiments, the weight percent of the cut microfibers in the heated multicomponent fiber slurry 301 is from about 10 weight percent to about 0.1 weight percent, from about 5 weight percent to about 0.2 weight percent, from about 3 weight percent to about 0.3 weight percent %, Or about 2% to about 0.4% by weight.

Any device known in the art that can mix the heated aqueous stream 801 with the cut multi-component fiber slurry 201 can be used in the mixing zone 300. Suitable devices include both continuous and batch mixing devices. In one embodiment, a mixing device suitable for mixing zone 300 includes a tank and a stirrer. In another embodiment, suitable mixing devices include pipes or conduits.

In another embodiment, a mixing device suitable for mixing zone 300 is a pipe or conduit having a diameter such that the velocity in the conduit is sufficient to mix the cut multicomponent fiber slurry 201 and the heated aqueous stream 801. In this case, less than about 2% by weight, less than about 1% by weight, or less than about 0.5% by weight of the cut multi-component material introduced per minute into the conduit is precipitated and accumulated in the conduit.

Subsequently, the heated multicomponent fiber slurry 301 can be sent to the fiber open zone 400. One function of the fiber opening zone 400 is to separate the water-dispersible polymer from the cut multi-component fibers so that at least a portion of the water non-dispersible polymer microfibers are separated from the cut multi-component fiber fibers and opened micro It is to be suspended in the fiber slurry 401. In another embodiment of the present invention, about 50 to about 100% by weight of the water non-dispersible polymer microfiber contained in the cut multi-component fiber slurry 201 can be added to the open microfiber slurry 401. Suspended as a non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber. In other embodiments, about 75 to about 100 weight percent, about 90 to about 100 weight percent, or about 95 to about 100 weight percent of the water non-dispersible polymer microfiber contained in the cut multicomponent fiber stream 201 Is suspended in the open microfiber slurry 401 as a water non-dispersible polymer microfiber and is no longer part of the cut multicomponent fiber.

The diameter or denier of the starting cut multicomponent fibers in stream 201 affects the degree to which water-dispersible sulfopolyester is separated from the multicomponent fibers in fiber open zone 400. Typical multicomponent fiber types generally have diameters ranging from about 12 microns to about 20 microns. Useful multicomponent fibers can have a larger starting diameter of about 40 microns or larger in diameter size. The time required to separate the desired amount of water dispersible sulfopolyester from the cut multicomponent fiber increases as the diameter of the cut multicomponent fiber in stream 201 increases.

The residence time, temperature and shear force in the fiber opening zone 400 also influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. Conditions affecting the opening process in the fiber opening zone 400 include residence time, slurry temperature and shear force, where the water temperature in the fiber opening zone 400, the range of residence time, and the degree of shear applied, are -To the extent that the dispersible polymer microfibers are separated and suspended in the continuous aqueous phase of the open microfiber slurry 401, it is governed by the need to separate the water dispersible sulfopolyester from the starting multicomponent fiber.

The residence time, temperature and shear force in the fiber opening zone 400 influence the degree of separation of the water dispersible sulfopolyester from the cut multicomponent fibers. The temperature of the fiber opening zone 400 may range from about 55 to about 100 ° C, from about 60 to about 90 ° C, or from about 65 to about 80 ° C. The residence time in the fiber opening zone 400 can range from about 5 minutes to about 10 seconds, from about 3 minutes to about 20 seconds, or from about 2 minutes to about 30 seconds. Sufficient mixing is maintained in the fiber open zone 400, so that the suspension of the cut water non-dispersible polymer microfibers is maintained such that settling of the cut microfibers is minimal. In another embodiment of the present invention, the mass per unit time of the cut water non-dispersible polymer microfibers in the fiber opening zone 400 is the mass per unit time of the water non-dispersible polymer microfibers entering the zone 400. Less than about 5%, less than about 3% of the mass per unit time of the number of non-dispersible polymer microfibers entering the zone 400, or of the number of non-dispersible polymer microfibers entering the zone 400 Less than about 1% of the mass per unit time.

Fiber opening in the fiber opening zone 400 can be achieved in any device that can allow for an acceptable residence time, temperature and mixing range. Examples of suitable devices include, but are not limited to, a stirred batch tank as shown in FIGS. 6B and 6C, a continuous stirred tank reactor, and a flow sufficient to minimize solid settling from the slurry as shown in FIG. 6A. Pipes are included. One example of a unit operation to achieve fiber opening in fiber opening zone 400 is a plug flow reactor, where heated multicomponent fiber slurry 301 is a zone 400 plug flow device, typically circular. It is sent by pipe or conduit. The residence time of the material in the plug flow device is calculated by dividing the filled volume in the device by the volume flow rate in the device. Material velocity in the device is defined as the cross-sectional area of the flow channel divided by the volumetric flow of liquid through the device.

In another embodiment of the invention, the fiber opening zone 400 may have a material flow rate in the pipe ranging from 0.1 to about 20 ft / sec, 0.2 to about 10 ft / sec, or about 0.5 to about 5 ft / sec. It may include pipes or conduits. For the flow of fluid or slurry in a pipe or conduit, the Reynolds number is a dimensionless number useful for describing the turbulence or motion of a fluid vortex that is irregular for both direction and time. For flow in a pipe or tube, the Reynolds number is generally defined as follows:

In the above formula,

D _H Is the hydraulic diameter (L) of the pipe (in meters);

Q is the volumetric flow rate (m ³ / s),

A is the pipe cross-sectional area (m ² ),

υ is the average velocity of the object relative to the fluid (SI unit: m / s),

μ is the dynamic viscosity of the fluid (Pa · s or N · s / m ² or kg / (m · s)),

v is the dynamic viscosity (v = μ / ρ) (m ² / s),

ρ is the density of the fluid (kg / m ³ ).

For flows in pipes of diameter D , experimental observations show that for fully developed flows, laminar flow occurs when Re _D is less than 2000 and turbulent flow when Re _D is greater than 4000. Between 2300 and 4000, layered and turbulent flows are possible ("transition" flows) depending on other factors, such as pipe roughness and flow uniformity.

The fiber open zone 400 may include pipes or conduits to facilitate the opening process, and the Reynolds number of flows through the pipes or conduits in the fiber open zone 400 ranges from about 2,100 to about 6,000, about 3,000 To about 6,000, or about 3,500 to about 6,000. In other embodiments, the fiber opening zone 400 can include a pipe or conduit to facilitate the opening process, wherein the Reynolds number of flows through the pipe or conduit is greater than 2,500, greater than about 3,500 or greater than about 4,000 to be.

The fiber opening zone 400 includes a pipe or conduit with a mixing device inserted in the pipe or conduit. The device may include an in-line mixing device. The in-line mixing device can be a static mixer without moving parts. In another embodiment, the in-line mixing device includes a movable portion. Non-limiting, such elements are mechanical devices for the purpose of imparting more mixed energy to the heated multicomponent fiber slurry 301, not achieved by flow through the pipe. The device can be inserted at the beginning of a pipe section used as a fiber opening zone, at the end of the pipe section, or at any location within the pipe flow path.

An open fiber slurry stream 401 comprising water non-dispersible polymer microfibers, water and water dispersible sulfopolyester is sent to a first solid-liquid separation zone 500, to provide a microfiber and a first mother liquor stream 501. A microfiber product stream 503 can be produced. In one embodiment, the first mother liquor stream 501 comprises water and water dispersible sulfopolyester.

The weight percent of solids in the open fiber slurry stream 401 can range from about 0.1 to about 20 weight percent, about 0.3 to about 10 weight percent, about 0.3 to about 5 weight percent, or about 0.3 to about 2.5 weight percent .

 The weight percent of solids in the microfiber product stream 503 can range from about 10 to about 65 weight percent, from about 15 to about 50 weight percent, from about 25 to about 45 weight percent, or from about 30 to about 40 weight percent.

Separating the microfiber product stream 503 from the open fiber slurry stream 401 can be accomplished by any method known in the art. In one embodiment, a wash stream 103 comprising water is sent to a first solid-liquid separation zone 500. The wash stream 103 can be used to wash the microfiber product stream in filter cloth media in the first solid-liquid separation zone 500 and / or the first solid-liquid separation zone 500 to produce a wash liquor stream 502. Fractions up to 100% by weight of the liquor stream 502 can be combined with the open fiber slurry stream 401 before entering the first solid-liquid separation zone 500. Fractions up to 100% by weight of the liquor stream 502 may be sent to a second solid-liquid separation zone 600. The liquor stream 502 may contain microfibers. In one embodiment, the g of microfiber mass passing through a filter medium having an opening of 200 microns or less in the first solid-liquid separation zone 500 ranges from about 1 to 2 g per cm ² of filter area. In other embodiments of the invention, the filter opening of the filter media in the first solid-liquid separation zone 500 may range from about 43 microns to 3000 microns, about 100 microns to 2000 microns, or about 500 microns to 2000 microns.

Separating the microfiber product stream from the microfiber slurry opened in the first solid-liquid separation zone 500 can be accomplished by one or several solid-liquid separation devices. Separation in the first solid-liquid separation zone 500 can be achieved by a batch and / or solid-liquid separation device or devices operated in a continuous manner. Suitable solid-liquid separation devices in the first solid-liquid separation zone 500 may include, but are not limited to, one of the following: perforated basket centrifuge, continuous vacuum belt filter, batch vacuum nutschfilter, batch perforated Settling tank, twin wire dewatering device, continuous horizontal belt filter with compression area, non-vibration inclined screen device with wedge wire filter media, continuous vacuum drum filter, dewatering conveyor belt, etc.

In one embodiment, the first solid-liquid separation zone 500 includes a twin wire dewatering device, wherein an open fiber slurry stream 401 is sent to the tapering gap between a pair of moving filter cloths moving in the same direction. . In the first zone of the twin wire dewatering device, water is drained due to gravity from the open fiber slurry stream 401 and from every narrow gap between the two moving filter cloths. In the downstream zone of the twin wire dewatering device, two filter cloths and a microfiber material between the two filter cloths are compressed more than once to mechanically reduce moisture in the microfiber material. In one embodiment, mechanical dewatering is accomplished by passing the two filter cloths and the contained microfiber material through a set of one or more rollers that exert a compressive force on the two filter cloths and the microfiber material between them. In another embodiment, mechanical dewatering is achieved by passing the two filter cloths and microfiber material through one or more sets of pressure rollers.

In another embodiment of the invention, the force exerted by mechanical dewatering for each set of pressure rollers ranges from about 25 to about 300 lbs per linear inch of filter media width, from about 50 to about 200 per linear inch of filter media width. in the lb range, or from about 70 to about 125 lb per linear inch of filter media width. The microfiber product stream 503 is discharged from the twin wire dewatering apparatus as the two filter cloths are separated and split in the solid discharge zone of the twin wire dewatering apparatus. The thickness of the microfiber material discharged may range from about 0.2 to about 1.5 inches, from about 0.3 to about 1.25 inches, or from about 0.4 to about 1 inch. In one embodiment, a stream of liquor comprising water is continuously applied to the filter medium. In another embodiment, a stream of liquor comprising water is periodically applied to the filter medium.

In another embodiment, the first solid-liquid separation zone 500 includes a belt filter device comprising a gravity drainage zone and a pressurized dehydration zone as illustrated in FIG. 7. The open microfiber slurry 401 is sent to a tapering gap between a pair of moving filter cloths moving in the same direction, which first passes through the gravity drainage zone and then in a serpentine arrangement as shown in Figure 6B. It passes through the pressurized dehydration zone or press zone included. As the belt is fed through the rollers, water escapes from the solid. In this process, when the belt passes through the final pair of rollers, the filter cloth is separated and solid is discharged from the belt filter device.

In another embodiment of the present invention, at least a portion of the water contained in the first mother liquor stream 501 comprising water and water dispersible sulfopolyester is recovered and recycled. The first mother liquor stream 501 may be recycled to the first solid-liquid separation zone 500. Depending on the efficiency of the first solid-liquid separation zone in the removal of water non-dispersible polymer microfibers, the first mother liquor stream 501 comprises a fiber slurry zone 200, a mixing zone 300, and a fiber opening zone 400. Alternatively, it may be recycled to the heat exchanger zone 800 before entering the zones 200, 300 and / or 400. The first mother liquor stream 501 may contain a small amount of solids comprising water non-dispersible polymer microfibers due to penetration and cloth washing. In one embodiment, g of the water non-dispersible polymer microfiber material passing through the filter medium in the first solid separation zone having an opening of 2000 microns or less ranges from about 1 to about 2 g per cm ² of filter area. . Before sending the first mother liquor stream 501 to the first enrichment zone 700 and the heat exchange zone 800 (in these zones, a number of non-dispersible polymer microfiber solids with negative effects can be collected and accumulated). It is desirable to minimize the number of non-dispersible polymer microfibers in stream 501.

The second solid-liquid separation zone 600 removes at least a portion of the water non-dispersible polymer microfiber solids present in the first mother liquor stream 501 to thereby remove the second wet cake comprising the water non-dispersible microfibers. It can function to generate a stream 602 and a second mother liquor stream 601 comprising water and water dispersible sulfopolyester.

In one embodiment, the second mother liquor stream 601 is sent to the first enrichment zone 700 and / or heat exchanger zone 800, where the second mother liquor stream 601 is sent to the first enrichment zone 700. ) May be in the range of 0 to 100%, and the remainder of the stream is sent to the heat exchanger zone 800. The second mother liquor stream 601 is a fiber slurry zone 200, a mixing zone 300, a fiber opening zone 400, or a heat exchanger zone before entering the zones 200, 300 and / or 400 It can be recycled to (800). The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Any portion of the second mother liquor stream 601 sent to the first concentration zone is subjected to a separation process to produce a first recovered water stream 703 and a first polymer concentrate stream 702 rich in water dispersible sulfopolyester. Produced, wherein the weight percent of the water dispersible sulfopolyester in the first polymer concentrate stream 702 can range from about 5 to about 85 weight percent, from about 10 to about 65 weight percent, or from about 15 to about 45 weight percent. have. The first recovered water stream 703 is heat exchange before entering the fiber slurry zone 200, the mixing zone 300, the fiber opening zone 400, or the zones 200, 300 and / or 400 It can be recycled to the base band 800. The amount of water-dispersible sulfopolyester in the second mother liquor stream sent to the fiber open zone 400 is about 0.01 to about 7 wt%, or about 0.1 to about 7 wt%, about 0.2 to about 5 weight percent, or about 0.3 to about 3 weight percent.

Water may be removed from the second mother liquor stream 601 in the first enrichment zone 700 by any method known in the art to produce a first polymer enrichment stream 702. In one embodiment, removal of water includes an evaporation process by boiling water in a batch or continuous evaporation apparatus. For example, one or more thin film evaporators can be used for this application. In another embodiment, the first polymer concentrate stream 702 can be produced using membrane technology comprising nanofiltration media. In another embodiment, a process comprising an extraction device can be used to extract the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. A combination of evaporation, membrane, and extraction steps can be used to separate the water-dispersible polymer from the second mother liquor stream 601 and produce a first polymer concentrate stream 702. The first polymer concentrate stream 702 can then be discharged out of the process.

In one embodiment, the first polymer concentrate stream 702 is sent to a second concentration zone 900, whereby the melted polymer stream 903 comprising water-dispersible sulfopolyester, wherein the weight percent of polymer is about 95 to about 100%) and steam stream 902 comprising water. In one embodiment, the stream 903 comprises water dispersible sulfopolyester. Suitable devices for the second concentration zone 900 include any device known in the art that can supply an aqueous dispersion of a water dispersible polymer and can produce a 95% to 100% water dispersible polymer stream 903. . This embodiment includes feeding an aqueous dispersion of the water-dispersible sulfopolyester polymer to the second concentration zone 900. The temperature of the feed stream is typically below 100 ° C.

In one embodiment, the second enrichment zone 900 is one or more devices characterized by a jacketed tubular shell containing a rotating transport screw, wherein the transport screw is heated with heat transfer fluid or steam Transport and high shear mixing elements). The jacket or shell is evacuated to allow steam to be removed. The shell jacket can be banded to allow different temperature set points along the length of the device. During continuous operation, the first polymer concentrate stream 702 includes water and water dispersible sulfopolyester, and is continuously fed to the second concentration zone 900. Within the device, there are at least three distinct and different forms of material in the steady state. The material in the device is first present as an aqueous dispersion of a water-dispersible sulfopolyester polymer. As the aqueous dispersion of sulfopolyester polymer moves through the device, water evaporates due to the heat of the jacket and the inner screw. When sufficient water is evaporated, the material becomes a second form comprising a viscous plug at a temperature lower than the melting point of the sulfopolyester polymer. The aqueous dispersion cannot flow past this viscous plug and is limited to the first aqueous dispersion zone of the device. Due to the heat of the jacket, the heat of the internally heated screw, and the heat due to the mixing shear force of this high-viscosity plug material, substantially all of the water present at this location is evaporated and the temperature is maintained until the melting temperature of the sulfoester is reached. Ascending, a third final physical form of the material comprising the molten sulfopolyester polymer is produced in the device. The molten sulfopolyester polymer is then exited the device through an extrusion die, typically cooled and cut into pellets in any manner known in the art. It should be understood that the device for the second enrichment zone 900 described above can also be operated in a batch mode, where the continuous of the viscous plug material and finally the sulfopolyester melt, starting with the aqueous dispersion throughout the length of the device. Three physical forms of the material described above occur in different time zones in sequence.

In one embodiment, the vapor generated in the second concentration zone 900 can be condensed and sent to the heat exchanger zone 800 and / or disposed of and / or sent to the wash stream 103. In another embodiment, condensed vapor stream 902 comprising water vapor can be sent to heat exchanger zone 800 to provide at least a portion of the energy required to generate the temperature required for stream 801. The molten polymer stream 903 comprising a water-dispersible polymer comprising sulfopolyester in the molten phase can be cooled and chopped into pellets by any method known in the art.

Impurities may be introduced into the process, and concentrated in water that is recovered and recycled. The concentration of impurities in the second mother liquor 601 and the first recovered water stream 701 may be adjusted to an acceptable level using one or more purge streams 603 and 701. In one embodiment, a portion of the second mother liquor stream 601 can be isolated and purged from the process. In one embodiment, a portion of the first recovered water stream 701 can be isolated and purged from the process.

The invention is further illustrated by the following examples.

[Example]

All pellet samples were pre-dried at room temperature under vacuum for at least 12 hours. The dispersion times listed in Table 3 are for complete dispersion or dissolution of the nonwoven sample. The abbreviation “CE” used in Tables 2 and 3 means “Comparative Example”.

Example  One

Ih.V of 0.29, containing 76 mol% of isophthalic acid, 24 mol% of sodiosulfoisophthalic acid, 76 mol% of diethylene glycol and 24 mol% of 1,4-cyclohexanedimethanol. And melt-blowing the sulfopolyester having a Tg of 48 ° C. onto a cylindrical collector through a nominal 6-inch die (30 holes / inch in the sample piece) using the conditions described in Table 1. Ordered. No interleafing paper was needed. A flexible, easy-to-handle flexible web was obtained that did not block during the roll winding operation. Physical properties are provided in Table 2. Small pieces of nonwoven (1 "× 3") were readily dispersed in both room temperature (RT) and 50 ° C water with slight shaking as shown by the data in Table 3.

[Table 1] Melting blow conditions

[Table 2] Physical properties of non-woven fabric

[Table 3] Dispersibility of nonwoven fabric

Example  2

Ih.V of 0.4 containing 89 mol% isophthalic acid, 11 mol% sodiosulfoisophthalic acid, 72 mol% diethylene glycol and 28 mol% ethylene glycol. And a sulfopolyester having a Tg of 35 ° C. was melt blown through a 6-inch die using conditions similar to those in Table 1. A flexible, easy-to-handle flexible web was obtained that did not block during the roll winding operation. Physical properties are provided in Table 2. Small pieces (1 "× 2") of the non-woven fabric were easily and completely dispersed at 50 ° C and 80 ° C, and at room temperature (23 ° C), a longer time was required for the textile to be completely dispersed as shown by the data in Table 3. .

It has been found that the compositions of Examples 1 and 2 can be blown top onto other nonwoven substrates. It can also be condensed and wrapped in a molded or contoured form that is used in place of a conventional web collector. Thus, a circular "roving" or plug form of the web can be obtained.

Comparative example ( CE ) 1 to 3

Ih.V of 0.4 containing 89 mol% isophthalic acid, 11 mol% sodiosulfoisophthalic acid, 72 mol% diethylene glycol and 28 mol% ethylene glycol. And pellets of sulfopolyester having a Tg of 35 ° C. were combined with polypropylene [Basell PF 008] pellets in the following two-component ratios (by weight percent):

75 PP: 25 sulfopolyester (Example 3)

50 PP: 50 sulfo polyester (Example 4)

25 PP: 75 sulfopolyester (Example 5)

PP had an MFR (melt flow rate) of 800. A melt blow operation was performed on a line equipped with a 24-inch wide die to obtain an easy-to-handle flexible flexible non-blocking web having the physical properties provided in Table 2. Small pieces (1 "× 4") of the nonwoven were easily dismantled as reported in Table 3. However, none of the fibers were completely water-dispersible due to the insoluble polypropylene component.

Example  3

A circular piece (4 "diameter) of the nonwoven fabric prepared in Example 2 was used as an adhesive layer between two cotton fabric sheets by applying a pressure of 35 psig at 200 DEG C for 30 seconds using a Hannifin melt press. The two sheets of cotton fabric were fused together The resulting assembly exhibited very strong bond strength The cotton substrate was finely divided before adhesion or bond breakage Similar results were obtained with other cellulose and PET polyester substrates. Strong bonds were also produced by the technique.

Comparative example  4

PP (Exxon 3356G) with an MFR of 1200 was melt blown using a 24 "die to obtain a flexible nonwoven that was unblocked and easily released from the roll. Small pieces (1" x4 ") There was no reaction when immersed in water at RT or 50 ° C. for 15 minutes (i.e., no dissolution or loss of basis weight).

Example  4

Monocomponent fiber of sulfopolyester containing 82 mol% isophthalic acid, 18 mol% sodiosulfoisophthalic acid, 54 mol% diethylene glycol and 46 mol% 1,4-cyclohexanedimethanol and having a Tg of 55 ° C Was melt spun at a melt temperature of 245 ° C (473 ° F) in a lab staple spinning line. The spinning denier was about 8 d / f. There was some blocking in the take-up tube, but the 10-filament strand readily dissolved within 10 to 19 seconds in 82 ° C. and unshaken demineralized water at pH 5-6.

Example  5

Sulfopolyester and isophthalic acid containing 82 mol% isophthalic acid, 18 mol% sodiosulfoisophthalic acid, 54 mol% diethylene glycol and 46 mol% 1,4-cyclohexanedimethanol (Tg at 55 ° C) Blend of sulfopolyesters containing 75% by mole of mol%, 9 mol% of sodiosulfoisophthalic acid, 25 mol% of diethylene glycol and 1,4-cyclohexanedimethanol (Tg at 65 ° C) (75:25) The monocomponent fibers obtained from each were melt spun in a wrap staple spinning line. The blend has a Tg of 57 ° C as calculated by taking a weighted average of the Tg of the component sulfopolyester. The 10-filament strand showed no blocking on the take-up tube, and readily dissolved in 20 to 43 seconds in 82 ° C and pH 5 to 6, unsalted demineralized water.

Example  6

The blend described in Example 5 was co-spun with PET to yield bicomponent island-in-the-sea fibers. A shape was obtained wherein the sulfopolyester “sea” was 20% by weight of fibers containing 80% by weight of PET “island”. The spinning yarn elongation was 190% immediately after spinning. No blocking was observed because the yarn was satisfactorily released from the bobbin and processed one week after spinning. In subsequent work, the “sea” was dissolved by passing the yarn through a 88 ° C. soft water bath, leaving only fine PET filaments.

Example  7

This putative example illustrates the possible use of the multicomponent and microdenier fibers of the present invention for the production of specialty paper. The blend described in Example 5 was co-spun with PET to obtain bicomponent island-in-the-sea fibers. The fiber contains about 35% by weight of sulfopolyester "sea" component and about 65% by weight of PET "island". Uncrimped fibers are cut to a length of 1/8 inch. In simulated papermaking, these short cut bicomponent fibers are added to the regeneration operation. The microdenier PET fibers are released into the mix by removing the sulfopolyester "sea" from the agitated aqueous slurry. At comparable weight, microdenier PET fibers ("islands") are more effective at increasing paper tensile strength than the addition of coarse PET fibers.

Comparative example  8

108 islands in the sea structure in a spin-bonding line using a 24 "wide bicomponent spinneret die from Hills Inc. of Melbourne, Florida, with a die hole of total multicomponent fiber counts on the die plate. Two extruders were connected to the melt pump, and the melt pump was again connected to the inlets for the two components of the fiber spinning die The main extruder (A) was designed to flow the Eastman F61HC PET polyester. Weighed and connected to the inlet creating an island domain in the fiber cross-section structure The extrusion zone was set to melt PET entering the die at 285 ° C. The auxiliary extruder (B) had an intrinsic viscosity of about 0.35 and a rheometric dynamic analyzer (Rheometric Dynamic Analyzer) RDAII [Rheometrics Inc., Piscataway, NJ] 240 ° C in flowmeter Eastman from Eastman Chemical Company, Kingsport, Tennessee, with a melt viscosity of about 15,000 poise when measured at a shear rate of 1 radian / sec, and 9,700 poise when measured at a shear rate of 240 ° C. and 100 radians / sec. AQ 55S sulfopolyester was processed.Before performing melt viscosity measurements, samples were dried for 2 days in a vacuum oven at 60 ° C. Viscosity tests were performed using a 25 mm diameter parallel plate configuration set at 1 mm intervals. The frequency sweep was performed in a strain rate range of 1 to 400 radians / second and a 10% strain width, and then the viscosity was measured at 240 ° C. and a strain rate of 1 radian / second. The viscosity of the ester material was determined: the auxiliary extruder melted the AQ 55S polymer and fed it to the spinneret die at a melt temperature of 255 ° C. Two polymers were produced as a two-component extrudate by extruding at a processing rate of 0.6 g / hole / minute The volume ratio of PET to AQ 55S in the two-component extrudate produced 60/40 and 70/30 ratios. Was adjusted.

The bicomponent extrudate was melt drawn using an inhaler device to produce bicomponent fibers. The fibers created by the air flow through the inhaler chamber were pulled down. The amount of air flowing downward through the inhaler assembly was adjusted by the pressure of the air entering the inhaler. In this example, the maximum pressure of air used in the inhaler to melt draw the bicomponent extrudate was 25 psi. Above this value, airflow through the inhaler destroyed the extrudate during this melt draw spinning process, because the rate of melt drawn on the bicomponent extrudate is greater than the inherent durability of the bicomponent extrudate. The bicomponent fibers were laid down with a nonwoven web having a fabric weight of 95 g / m ² (gsm). The evaluation of the bicomponent fibers in this nonwoven web by optical microscopy shows that PET is present as an island in the center of the fiber structure, but the PET islands around the outer periphery of the bicomponent fibers are cohesively cohesively resulting in almost no PEE polymer circumference around the fiber It has been shown to form a continuous ring (which is undesirable). Microscopy revealed that the diameter of the bicomponent fibers in the nonwoven web is generally 15 to 19 microns, corresponding to an average fiber spinning denier of about 2.5 denier / filament (dpf). This provides a melt drawn fiber speed of about 2160 m / min. Spinning denier is defined as the denier of a fiber (weight (g) of 9000 meters in length) obtained by melt extrusion and melt drawing. Changes in the diameter of the bicomponent fibers showed non-uniformity in spinning-drawing of the fibers.

Nonwoven web samples were conditioned in a forced-air oven at 120 ° C. for 5 minutes. The heat treated web showed a significant shrinkage rate, and the area of the nonwoven web was reduced to about 12% of the initial area of the web before heating. Without wishing to be bound by any particular theory, due to the high molecular weight and melt viscosity of the AQ 55S sulfopolyester used in the fibers, the bicomponent extrudates are melt drawn to the extent necessary to cause deformation-induced crystallization of the PET compartment within the fibers. Could not be. As a result, AQ 55S sulfopolyester with this specific intrinsic viscosity and melt viscosity was unacceptable because the bicomponent extrudate could not be uniformly melt drawn to the desired fine denier.

Example  8

A sulfopolyester polymer having the same chemical composition as the commercially available Eastman AQ55S polymer was produced, but the molecular weight was adjusted to a lower value characterized by an intrinsic viscosity of about 0.25. The melt viscosity of this polymer was 3300 poise when measured at 240 ° C. and a shear rate of 1 radian / second.

Example  9

Two-component compression with a 16-compartment divided pie structure using a two-component spinneret die, a Hills Inc. (Melbourne, FL) article with a total of 2222 die holes on a 24-inch wide die plate on a spin bonding facility. Water was prepared. Two polymers were melted using two extruders and fed to this spinneret die. The main extruder (A) was fed to the Eastman F61HC PET polyester melt and connected to the inlet to form a domain or compartment slice in a divided pie cross-section structure. The extrusion zone was set to melt PET entering the spinneret die at 285 ° C. The auxiliary extruder (B) melted and fed the sulfopolyester polymer of Example 8. The auxiliary extruder was set up to extrude the sulfopolyester polymer into the spinneret die at a melt temperature of 225 ° C. The procedure used in this example was the same as in Comparative Example 8, except for the melt viscosity of the spinneret die and sulfopolyester polymer used. The melt throughput per hole was 0.6 gm / min. The volume ratio of PET to sulfopolyester in the bicomponent extrudate was set to 70/30, representing a weight ratio of about 70/30.

The bicomponent extrudate was melt drawn using the same inhaler as used in Comparative Example 8 to produce bicomponent fibers. First, the inlet air to the inhaler was set to 25 psi, the fibers had a spin denier of about 2.0, and the bicomponent fibers exhibited a uniform diameter profile of about 14 to 15 microns. The air to the inhaler was increased to a maximum available pressure of 45 psi without breaking the melt extrudate during melt drawing. Using 45 psi of air, the bicomponent extrudate was melt drawn down to a fiber spinning denier of about 1.2, and the bicomponent fibers showed a diameter of 11 to 12 microns when viewed under a microscope. The speed during the melt drawing process was calculated to be about 4500 m / min. Without wishing to be bound by any particular theory, it is believed that at the melt draw rate approaching this rate, deformation-induced crystallization of PET during the melt draw process begins to occur. As indicated above, it is desirable to form some oriented crystallinity in the PET fiber compartment during the fiber melt drawing process so that the nonwoven web is more dimensionally stable during subsequent processing.

The bicomponent fibers were laminated to a nonwoven web having a weight of 140 g / m ² (gsm) using an inhaler air pressure of 45 psi. The shrinkage of the nonwoven web was measured by conditioning the material in a forced-air oven at 120 ° C. for 5 minutes. This example shows a significant reduction in shrinkage compared to the fibers and fabrics of Comparative Example 8.

This nonwoven web having a 140 gsm fabric weight was immersed in a static deionized water bath at various temperatures for 5 minutes. The immersed nonwoven web was dried, and the weight loss% due to immersion in deionized water at various temperatures was measured and the results are shown in Table 4 below.

[Table 4]

The sulfopolyester dissipated very easily in deionized water at about 25 ° C. The removal of sulfopolyester from bicomponent fibers of the nonwoven web is indicated by% weight loss. Above 33 ° C, extensive or complete removal of sulfopolyester from bicomponent fibers was observed. When high pressure weaving is used to create the nonwoven webs of these bicomponent fibers comprising the present sulfopolyester of Example 8, the sulfopolyester polymer is widely or extensively by high water pressure woven jet water if the water temperature is higher than the ambient temperature. It is expected to be completely eliminated. If it is desired that little sulfopolyester polymer is removed from these bicomponent fibers during the high pressure weaving step, a low water temperature of less than about 25 ° C should be used.

Example  10

Sulfopolyester polymers were prepared with the following diacid and diol compositions: diacid compositions (71 mol% of terephthalic acid, 20 mol% of isophthalic acid and 9 mol% of 5- (sodiosulfo) isophthalic acid) and diol compositions (ethylene glycol 60 Mol% and diethylene glycol 40 mol%). Sulfopolyester was prepared by high temperature polyesterification under vacuum. The esterification conditions were adjusted to produce sulfopolyester with an intrinsic viscosity of about 0.31. The melt viscosity of this sulfopolyester was measured to be about 3000 to 4000 poises at 240 ° C. and a shear rate of 1 radian / second.

Example  11

The sulfopolyester polymer of Example 10 was spun into bicomponent divided pie fibers and nonwoven webs following the same procedure as described in Example 9. The main extruder (A) fed the Eastman F61HC PET polyester melt to form a larger compartment slice of a divided pie structure. The extrusion zone was set to melt PET entering the spinneret die at 285 ° C. The auxiliary extruder (B) processed the sulfopolyester polymer of Example 10 fed to a spinneret die at a melt temperature of 255 ° C. The rate of melt treatment per hole was 0.6 gm / min. The volume ratio of PET to sulfopolyester in the bicomponent extrudate was set to 70/30, which represents a weight ratio of about 70/30. The cross-section of the bicomponent extrudate had a wedge-shaped domain of PET and a sulfopolyester polymer separating these domains.

The bicomponent extrudate was melt drawn using the same inhaler assembly used in Comparative Example 8 to produce bicomponent fibers. The maximum air pressure that could be used as an inhaler without breaking bicomponent fibers during drawing was 45 psi. Using 45 psi of air, the bicomponent extrudate was melt drawn down to produce a bicomponent fiber with a spin denier of about 1.2, which exhibits a diameter of about 11 to 12 microns when viewed under a microscope. Did. The speed during the melt drawing process was calculated to be about 4500 m / min.

Bicomponent fibers were laminated with a nonwoven web having a weight of 140gsm and 110gsm. The shrinkage of the web was measured by conditioning the material for 5 minutes at 120 ° C. in a forced-air oven. The area of the nonwoven web after shrinkage was about 29% of the starting area of the web.

Microscopic examination of the cross-sections of the fibers drawn from the melt drawn fibers and the nonwoven web showed that the individual sections were clearly defined and exhibited very good divided pie structures exhibiting similar sizes and shapes. The PET compartments were completely separated from each other, and after removing the sulfopolyester from the bicomponent fibers, eight separate PET monocomponent fibers having a pi-slice shape were produced.

A nonwoven web having a fabric weight of 110 gsm was immersed in a static deionized water bath at various temperatures for 8 minutes. The immersed nonwoven web was dried, and the weight loss% due to immersion in deionized water at various temperatures was measured and the results are shown in Table 5 below.

[Table 5]

The sulfopolyester polymer was readily dissipated in deionized water at a temperature higher than about 46 ° C, and the removal of the sulfopolyester polymer from the fibers was very broad or complete at temperatures higher than 51 ° C as seen by weight loss. A weight loss of about 30% indicated that the sulfopolyester was completely removed from the bicomponent fibers of the nonwoven web. When processing this nonwoven web of bicomponent fibers comprising this sulfopolyester using high water pressure weaving, it is expected that the polymer will not be extensively removed by high water pressure weaving spray water below 40 ° C.

Example  12

The nonwoven web of Example 11 with basis weights of 140 gsm and 110 gsm was woven high pressure using a high water pressure weaving device manufactured by Fleisner, GmbH (Egelsbach, Germany). The machine has a total of five high-pressure weaving stations, where three sets of jets contact the top of the nonwoven web and two sets of jets contact the opposite side of the nonwoven web. The water jet contained a series of micropores of about 100 microns in diameter engineered into a 2 foot wide jet strip. The spray water pressure was set to 60 bar (jet strip # 1), 190 bar (jet strip # 2 and 3) and 230 bar (jet strip # 4 and 5). During the high-pressure weaving process, the spray water temperature was found to be about 40-45 ° C. The nonwovens present in the high pressure weaving machine were tightly bonded together. The continuous fibers were entangled together, resulting in a high pressure woven nonwoven fabric with high tear resistance when stretched in both directions.

The high pressure woven nonwoven was then secured on a tenter frame comprising a rigid rectangular frame with a series of pins around it. The fabric was pinned to limit the shrinkage of the fabric when it was heated. The frame equipped with the fabric sample was placed in a forced-air oven at 130 ° C. for 3 minutes to heat cure the fabric for a limited period. After heat curing, the conditioned fabric was cut into specimens of the measured size, and the specimens were conditioned at 130 ° C. without limitation by the tenter frame. After this conditioning, the dimensions of the high-pressure woven nonwoven were measured, and only minimal shrinkage (diameter reduction of less than 0.5%) was observed. It was evident that the thermal curing of the high pressure woven nonwoven is sufficient to produce a dimensionally stable nonwoven.

After heat curing as described above, the high pressure woven nonwoven was washed in deionized water at 90 ° C. to remove the sulfopolyester polymer and left a PET monocomponent fiber compartment on the high pressure woven fabric. After repeated washing, the dried fabric exhibited a weight loss of about 26%. Washing the non-woven fabric before high-pressure weaving showed a weight loss of 31.3%. Thus, the high-pressure weaving process partially removed the sulfopolyester from the nonwoven web, but this amount was relatively small. In order to reduce the amount of sulfopolyester removed during high water pressure weaving, the high water pressure weaving spray water temperature must be lowered below 40 ° C.

It has been found that the sulfopolyester of Example 10 provides split pie fibers with good compartment distribution (water non-dispersible polymer compartments yield individual fibers of similar size and shape after removal of the sulfopolyester polymer). . The rheology of the sulfopolyester was suitable to achieve a bicomponent fiber of fine denier with a low spin denier of about 1.0 by melt drawing a bicomponent extrudate at high speed. These bicomponent fibers could be layered into a nonwoven web, and these nonwoven webs were highly hydraulic woven without significant loss of sulfopolyester polymer to produce nonwovens. The nonwoven fabric produced by the high pressure weaving of the nonwoven web exhibited high strength and was heat cured at a temperature of about 120 ° C. or higher to produce a nonwoven fabric having excellent dimensional stability. The sulfopolyester polymer was removed from the high pressure woven nonwoven in the washing step. The result was a strong nonwoven article with lighter fabric weight and much greater flexibility and soft feel. The monocomponent PET fibers of this nonwoven article had a wedge shape and exhibited an average denier of about 0.1.

Example  13

Sulfopolyester polymers were prepared with the following diacid and diol compositions: diacid compositions (69 mol% of terephthalic acid, 22.5 mol% of isophthalic acid and 8.5 mol% of 5- (sodiosulfo) isophthalic acid) and diol composition (65 mol%) Ethylene glycol and 35 mol% diethylene glycol). Sulfopolyester was prepared by high temperature polyesterification under vacuum. The esterification conditions were adjusted to produce sulfopolyester with an intrinsic viscosity of about 0.33. The melt viscosity of this sulfopolyester was measured to be in the range of about 3000 to 4000 poise at 240 ° C. and a shear rate of 1 radian / second.

Example  14

The sulfopolyester polymer of Example 13 was spun into a bicomponent island-in-the-sea (having 16 islands) cross-sectional shape in a spinning bonding line. The main extruder (A) fed the Eastman F61HC PET polyester melt to create islands of the island's structure. The extrusion zone was set to melt the PET entering the spinneret at about 290 ° C. The auxiliary extruder (B) processed the sulfopolyester polymer of Example 13 fed to the spinneret die at a melt temperature of about 260 ° C. The volume ratio of PET to sulfopolyester in the bicomponent extrudate was set to 70/30, representing a weight ratio of about 70/30. The rate of melt treatment through spinneret was 0.6 g / hole / min. The cross-section of the bicomponent extrudate had a rounded PET island domain separated by a sulfopolyester polymer.

The bicomponent extrudate was melt drawn using an inhaler assembly. The maximum pressure of air available to the inhaler without breaking the bicomponent fibers during melt drawing was 50 psi. Using 50 psi of air, the bicomponent extrudate was melt drawn down to obtain a bicomponent fiber with a spin denier of about 1.4, which exhibited a diameter of about 12 microns when viewed under a microscope. The speed during the drawing process was calculated to be about 3900 m / min.

Example 15

The sulfopolyester polymer of Example 13 was spun into bicomponent island-in-the-sea fibers with 64 island fibers using a bicomponent extrusion line. The primary extruder formed an island in the fiber cross-section structure even by feeding the Eastman F61HC polyester melt. The secondary extruder formed a sea in bicomponent fibers even by feeding a sulfopolyester polymer melt. The inherent viscosity of the polyester was 0.61 dL / g and the melt viscosity of the dry sulfopolyester was about 7000 poise as measured at 240 ° C. and 1 rad / sec strain using the melt viscosity measurement procedure described above. The island-in-sea bicomponent fiber was made using a spinneret having 198 holes and a throughput rate of 0.85 gm / min / hole. The polymer ratio between "island" polyester and "sea" sulfopolyester was 65% to 35%. The bicomponent fiber was spun using an extrusion temperature of 280 ° C for the polyester component and an extrusion temperature of 260 ° C for the sulfopolyester component. The bicomponent fiber contained a number of filaments (198 filaments) and melt spun at a rate of about 530 meters / minute to form a filament with a nominal d / f of about 14. A 24% by weight finish solution of PT 769 finish from Goulston Technologies was applied to bicomponent fibers using a kiss roll applicator. Thereafter, the filaments of the bicomponent fibers were stretched in line using a set of two godet rolls heated to 90 ° C and 130 ° C, respectively, and then stretched to a final stretching roll operated at a speed of about 1750 meters / minute, to about A filament draw ratio of 3.3X was provided to form stretched island-in-sea bicomponent filaments having a nominal d / f of about 4.5 or an average diameter of about 25 microns. The filament consisted of polyester microdenier fiber "islands" having an average diameter of about 2.5 microns.

Example 16

The stretched island-in-sea bicomponent fibers of Example 15 were cut into short length fibers of 3.2 millimeters and 6.4 millimeters cut length, thereby producing short-length bicomponent fibers with 64 island-in-sea cross-sectional structures. The short-cut bicomponent fibers consisted of "islands" of polyester and "sea" of water-dispersible sulfopolyester polymers. The cross-sectional distributions of the island and the sea were essentially consistent along the length of these short-cut bicomponent fibers.

Example 17

The stretched island-in-sea bicomponent fibers of Example 15 were immersed in soft water for about 24 hours and then cut into short length fibers of 3.2 mm and 6.4 mm cut lengths. The water-dispersible sulfopolyester was emulsified at least partially before being cut into short length fibers. Thus, partial separation of the islands from the sea component was achieved, thereby producing bicomponent fibers even with partially emulsified short lengths.

Example 18

The short-cut length of the island-in-the-sea bicomponent fiber of Example 16 was washed with soft water at 80 ° C. to remove the water-dispersible sulfopolyester “sea” component, whereby the polyester micro which was the “island” component of the bicomponent fiber. The fibers were released. The washed polyester microfibers were washed with soft water at 25 ° C. to essentially remove most of the “sea” components. The optical microscopic observation of the washed polyester microfibers showed an average diameter of about 2.5 microns and lengths of 3.2 and 6.4 millimeters.

Example 19

The partially emulsified island-in-the-sea fiber of Example 17 was washed with soft water at 80 ° C. to remove the water-dispersible sulfopolyester “sea” component, whereby the polyester that was the “island” component of the fiber. The microfiber was released. The washed polyester microfibers were washed with soft water at 25 ° C. to essentially remove most of the “sea” components. The optical microscopic observation of the washed polyester microfibers showed polyester microfibers with an average diameter of 2.5 microns and lengths of 3.2 and 6.4 millimeters.

Comparative Example 20

Wet-laminated hand sheets were prepared using the following procedure. 7.5 gm of Alba Southern Southern Bleached Softwood Kraft (SBSK) and 188 gm of room temperature water from International Paper, Memphis, Tennessee, USA were placed in a 1000 ml pulp mill and placed for 30 seconds. A pulped mixture was prepared by pulping at 7000 rpm. This pulped mixture was transferred to an 8 liter metal beaker with 7312 gm of room temperature water to make about 0.1% consistency (7500 gm water and 7.5 gm fibrous material) to prepare a pulp slurry. This pulp slurry was shaken for 60 seconds using a high speed impeller mixer. The procedure for manufacturing a hand sheet from this pulp slurry is as follows. The pulp slurry was poured into a 25 cm x 30 cm hand sheet mold with continued stirring. The drop valve was pulled, and the pulp fibers flowed onto the screen to form a hand seat. A 750 g / m ² (gsm) blotter paper was placed on top of the formed hand sheet, and the blotter paper was flattened onto the hand sheet. The screen frame was raised and turned over on a transparent release paper and placed for 10 minutes. The screen was lifted vertically from the formed hand sheet. Two 750gsm blotter papers were placed on top of the formed hand sheet. The hand sheet was dried with a blotter paper of 3 sheets using a Norwood Dryer at about 88 ° C. for 15 minutes. One blotter paper was removed to leave one blotter paper on each side of the hand sheet. The hand sheet was dried at 65 ° C. for 15 minutes using a Williams Dryer. The hand sheet was then also dried using a 40 kg dry press for 12 to 24 hours. The blotter paper was removed to obtain a dry hand sheet sample. The hand sheet was trimmed to 21.6 cm × 27.9 cm dimensions for testing.

Comparative Example 21

Wet-laminated hand sheets were prepared using the following procedure. Albacel Southern Bleached Softwood Craft (SBSK) made from 7.5 gm of International Paper of Memphis, Tennessee, USA, 0.3 gm of pre-gelatinized quaternary cationic made from Avebe of Foxhall, The Netherlands A pulped mixture was prepared by placing potato starch, Solvitose N, and 188 gm of room temperature water in a 1000 ml pulp maker and pulping for 30 seconds at 7000 rpm. This pulped mixture was transferred to an 8 liter metal beaker with 7312 gm of room temperature water to make a concentration of about 0.1% (7500 gm water and 7.5 gm fibrous material) to prepare a pulp slurry. This pulp slurry was shaken for 60 seconds using a high speed impeller mixer. The rest of the procedure for making a hand sheet from this pulp slurry is the same as in Example 20.

Example 22

Wet-laminated hand sheets were prepared using the following procedure. Albacel Southern Bleached Softwood Craft (SBSK), manufactured from International Paper, Memphis, Tennessee, 6.0gm, Pre-gelatinized quaternary cationic potato starch, made from Abbe, Foxhall, The Netherlands, 0.3gm Solvitose N, 1.5 gm of Example 16 3.2 millimeter cut length fiber of Example 16, and 188 gm of room temperature water were placed in a 1000 ml pulp maker and pulped at 7000 rpm for 30 seconds to prepare a fiber mixture slurry. The fiber mixture slurry was emulsified by heating to 82 ° C. for 10 seconds to remove the water-dispersible sulfopolyester component in the fibers, thereby releasing polyester microfibers. The fiber mixture slurry was then modified to prepare a sulfopolyester dispersion comprising a sulfopolyester and a microfiber-containing mixture comprising pulp fibers and polyester microfibers. The microfiber-containing mixture was also washed with 500 gm of room temperature water to also remove the water dispersible sulfopolyester from the microfiber-containing mixture. This microfiber-containing mixture was transferred to an 8 liter metal beaker with 7312 gm of room temperature water to make a concentration of about 0.1% (7500 gm water and 7.5 gm fibrous material) to prepare a microfiber-containing slurry. This microfiber-containing slurry was shaken for 60 seconds using a high speed impeller mixer. The rest of the procedure for making a hand sheet from this microfiber-containing slurry is the same as in Example 20.

Comparative Example 23

Wet-laminated hand sheets were prepared using the following procedure. 7.5 gm of MicroStrand 475-106 micro glass fiber available from Johns Manville, Denver, Colorado, USA, 0.3 gm of pre-gelatinized quaternary cation made from Abbe, Foxhole, The Netherlands. A glass fiber mixture was prepared by placing sex potato starch, Solvitose N, and 188 gm of room temperature water in a 1000 ml pulp maker and pulping at 7000 rpm for 30 seconds. The glass fiber mixture was transferred to an 8 liter metal beaker with 7312 gm of room temperature water to make a concentration of about 0.1% (7500 gm water and 7.5 gm fibrous material) to prepare a glass fiber slurry. The glass fiber slurry was shaken for 60 seconds using a high speed impeller mixer. The rest of the procedure for making a hand sheet from this glass fiber slurry is the same as in Example 20.

Example 24

Wet-laminated hand sheets were prepared using the following procedure. MicroStrand 475-106 micro glass fiber available from Jones Manville, Denver, Colorado, 3.8 gm, 3.2 millimeter cut length fiber of Example 16, 3.8 gm, from Abbe, Foxhole, Netherlands, 0.3 gm The prepared pre-gelatinized quaternary cationic potato starch, Solvitose N, and 188 gm of room temperature water were placed in a 1000 ml pulp maker and pulped at 7000 rpm for 30 seconds to prepare a fiber mixture slurry. Even if the fiber mixture slurry was emulsified by heating at 82 ° C. for 10 seconds, the water-dispersible sulfopolyester component in the bicomponent fiber was removed to release polyester microfibers. The fiber mixture slurry was then modified to produce a sulfopolyester dispersion comprising a sulfopolyester and a microfiber-containing mixture comprising glass microfibers and polyester microfibers. The microfiber-containing mixture was also washed with 500 gm of room temperature water to also remove the sulfopolyester from the microfiber-containing mixture. The microfiber-containing mixture was transferred to an 8 liter metal beaker with 7312 gm of room temperature water to make a concentration of about 0.1% (7500 gm water and 7.5 gm fibrous material) to prepare a microfiber-containing slurry. This microfiber-containing slurry was shaken for 60 seconds using a high speed impeller mixer. The rest of the procedure for making a hand sheet from this microfiber-containing slurry is the same as in Example 20.

Example 25

Wet-laminated hand sheets were prepared using the following procedure. Solventos N, a pre-gelatinized quaternary cationic potato starch made from Abebe, Foxhole, The Netherlands, of 0.3 gm of 3.2 millimeter cut length fiber of Example 16 of 7.5 gm, and 1000 ml of room temperature water of 188 gm of pulp A fiber mixture slurry was prepared by placing it in a machine and pulping at 7000 rpm for 30 seconds. The fiber mixture slurry was emulsified by heating to 82 ° C. for 10 seconds to remove the water-dispersible sulfopolyester component in the fibers, thereby releasing polyester microfibers. Thereafter, the fiber mixture slurry was modified to prepare a sulfopolyester dispersion and polyester microfibers. The sulfopolyester dispersion consisted of water-dispersible sulfopolyester. The sulfopolyester was also removed from the polyester microfiber by washing the polyester microfiber with 500 gm of room temperature water. The polyester microfiber was transferred to an 8 liter metal beaker with 7312 gm of room temperature water to a concentration of about 0.1% (7500 gm water and 7.5 gm fibrous material) to prepare a microfiber slurry. This microfiber slurry was shaken for 60 seconds using a high speed impeller mixer. The rest of the procedure for making a hand sheet from this microfiber slurry is the same as in Example 20.

The hand sheet samples of Examples 20-25 were tested and the properties are provided in Table 6 below.

[Table 6]

The hand sheet basis weight is determined by weighing the hand sheet and calculating it in grams weight per square meter (gsm). Hand sheet thickness was measured using an Ono Sokki EG-233 thickness gauge and reported in millimeter thickness. Density was calculated as gram weight per cubic centimeter. Porosity was measured using a Greiner porosity manometer with a 1.9x1.9 cm square opening head and 100 cc capacity. The porosity of 100 cc was measured using the Instron Model TM for six 30 mm × 105 mm test strips. The average of the six measurements was reported for each example. From the above test data, it can be observed that by adding the polyester microfiber of the present invention, a significant improvement in tensile properties of the wet-laid fibrous structure is obtained.

Example 26

The sulfopolyester polymer of Example 13 was spun into bicomponent island-in-the-sea fibers with 37 island fibers using a bicomponent extrusion line. The primary extruder formed "islands" in the cross-sectional structure even if Eastman F61HC polyester was supplied. The secondary extruder formed "sea" in bicomponent fibers even by supplying a water-dispersible sulfopolyester polymer. The intrinsic viscosity of the polyester was 0.61 dL / g, and the melt viscosity of the dry sulfopolyester was about 7000 poise when measured at 240 ° C. and 1 rad / sec strain using the aforementioned melt viscosity measurement procedure. This island-in-sea bicomponent fiber was prepared using a spinneret with 72 holes and a throughput rate of 1.15 gm / min / hole. The polymer ratio between “island” polyester and “sea” sulfopolyester was 2 to 1. This bicomponent fiber was spun using an extrusion temperature of 280 ° C for the polyester component and an extrusion temperature of 255 ° C for the water-dispersible sulfopolyester component. This bicomponent fiber contained a number of filaments (198 filaments) and melt spun at a rate of about 530 meters / minute to form a filament with a nominal d / f of 19.5. A 24% by weight finish solution of PT 769 finish from Goulston Technologies was applied to bicomponent fibers using a kiss roll applicator. Thereafter, the filaments of the bicomponent fibers were stretched in one row using a set of two Godet rolls heated to 95 ° C and 130 ° C, respectively, and then stretched to a final stretching roll operated at a rate of about 1750 meters / minute, to about 3.3X. The filament elongation ratio was provided to form stretched island-in-sea bicomponent filaments having a nominal d / f of about 5.9 or an average diameter of about 29 microns. The filament consisted of polyester microfiber "islands" having an average diameter of about 3.9 microns.

Example 27

The stretched island-in-sea bicomponent fibers of Example 26 were cut into short-length bicomponent fibers of 3.2 mm and 6.4 mm cut lengths, thereby producing short-length fibers with 37 islands of island-in-sea cross-sectional structure. The fibers consisted of "islands" of polyester and "sea" of water-dispersible sulfopolyester polymers. The cross-sectional distributions of “islands” and “seas” were essentially consistent along the length of the bicomponent fibers.

Example 28

The short-cut length island-in-the-sea fiber of Example 27 was washed with soft water at 80 ° C. to remove the water-dispersible sulfopolyester “sea” component, whereby the polyester microfiber that was the “island” component of the bicomponent fiber was removed. Released. The washed polyester microfibers were washed with soft water at 25 ° C. to essentially remove most of the “sea” components. The washed polyester microfibers were observed with an optical microscope to have an average diameter of about 3.9 microns and lengths of 3.2 and 6.4 millimeters.

Example 29

The sulfopolyester polymer of Example 13 was spun into bicomponent island-in-the-sea fibers with 37 island fibers using a bicomponent extrusion line. The primary extruder formed "islands" in the fiber cross-sectional structure even when polyester was supplied. The secondary extruder formed "sea" in bicomponent fibers even by supplying a water-dispersible sulfopolyester polymer. The intrinsic viscosity of the polyester was 0.52 dL / g, and the melt viscosity of the dry water-dispersible sulfopolyester was about 3500 poise as measured at 240 ° C. and 1 rad / sec strain using the aforementioned melt viscosity measurement procedure. The island-in-sea bicomponent fibers were prepared using two spinnerets each having 175 holes and a throughput rate of 1.0 gm / min / hole. The polymer ratio between “island” polyester and “sea” sulfopolyester was 70% to 30%. This bicomponent fiber was spun using an extrusion temperature of 280 ° C for the polyester component and an extrusion temperature of 255 ° C for the sulfopolyester component. This bicomponent fiber contained a large number of filaments (350 filaments) and was melt spun at a rate of about 1000 meters / minute using a winding roll heated to 100 ° C. to give a nominal d / f of about 9 and an average of about 36 microns. A filament having a fiber diameter was formed. A solution of 24% by weight of the PT 769 finish was applied to the bicomponent fibers using a kiss roll applicator. After the filaments of the bicomponent fiber are combined, stretched at a stretch roll speed of 100 m / min and at a temperature of 38 ° C. to 3.0 × on a stretch line to a stretched chart isomer having an average diameter of about 3 and an average diameter of about 20 microns. Minute filaments were formed. The stretched island-in-sea bicomponent fibers were cut into short length fibers of about 6.4 millimeters in length. The short length, even bicomponent fiber consisted of a polyester microfiber "island" with an average diameter of about 2.8 microns.

Example 30

The short-cut length of the even-cut fiber of Example 29 was washed with soft water at 80 ° C. to remove the water-dispersible sulfopolyester “sea” component, whereby the polyester microfiber that was the “island” component of the fiber was removed. Released. The washed polyester microfibers were washed with soft water at 25 ° C. to essentially remove most of the “sea” components. The washed fibers were observed with an optical microscope to show polyester microfibers with an average diameter of about 2.8 microns and a length of about 6.4 millimeters.

Example 31

A wet-laid microfiber raw hand sheet was prepared using the following procedure. Even with the 3.2 millimeter cut length of Example 16 of 56.3 gm, bicomponent fibers, 2.3 gm of pre-gelatinized quaternary cationic potato starch, Solvitose N, manufactured by Abbe, Foxhole, The Netherlands, and room temperature water of 1410 gm. A fiber slurry was prepared by placing it in a 2 liter beaker. The fiber slurry was stirred. About 352 ml, an amount of 1/4 of this fiber slurry, was placed in a 1000 ml pulp maker and pulped for 30 seconds at 7000 rpm. Even if the fiber slurry was emulsified by heating to 82 ° C. for 10 seconds, the water-dispersible sulfopolyester component in the bicomponent fiber was removed and the polyester microfiber was released. Subsequently, the fiber slurry was modified to prepare a sulfopolyester dispersion and polyester microfibers. The polyester microfiber was also washed with 500 gm of room temperature water to remove sulfopolyester from the polyester microfiber. Sufficient room temperature water was added to prepare 352 ml of microfiber slurry. This microfiber slurry was repulped for 30 seconds at 7000 rpm. The microfiber was transferred to an 8 liter metal beaker. The remaining three quarters of the fiber slurry were similarly pulped, washed, washed and repulped and transferred to an 8 liter metal beaker. Thereafter, 6090 gm of room temperature water was added to make a concentration of about 0.49% (7500 gm water and 36.6 gm polyester microfiber) to prepare a microfiber slurry. This microfiber slurry was shaken for 60 seconds using a high speed impeller mixer. The rest of the procedure for making a hand sheet from this microfiber slurry is the same as in Example 20. The microfiber stock hand sheet with a basis weight of about 490 gsm was made of polyester microfibers with an average diameter of about 2.5 microns and an average length of about 3.2 millimeters.

Example 32

Wet-laminated hand sheets were prepared using the following procedure. 7.5 gm of the polyester microfiber raw material hand sheet of Example 31, 0.3 gm of pre-gelatinized quaternary cationic potato starch Solvitose N made from Abbe, Foxhole, The Netherlands, and 1000 ml of room temperature water of 188 gm It was placed in a pulp maker and pulped at 7000 rpm for 30 seconds. The microfiber slurry was prepared by transferring the microfiber to an 8 liter metal beaker with 7312 gm of room temperature water to make a concentration of about 0.1% (7500 gm water and 7.5 gm fibrous material). This microfiber slurry was shaken for 60 seconds using a high speed impeller mixer. The rest of the procedure for making a hand sheet from this slurry is the same as in Example 20. A 100 gsm wet-laid hand sheet of polyester microfibers having an average diameter of about 2.5 microns was obtained.

Example 33

Even if the 6.4 millimeter cut length of Example 29 was used, the bicomponent fiber was washed with soft water at 80 ° C. to remove the water-dispersible sulfopolyester “sea” component, whereby the polyester micro which was the “island” component of the bicomponent fiber. The fibers were released. The washed polyester microfibers were washed with soft water at 25 ° C. to essentially remove most of the “sea” components. The washed polyester microfibers were observed with an optical microscope to show an average diameter of about 2.5 microns and a length of 6.4 millimeters.

Example 34

About 1% by weight of the short-cut island-in-the-sea bicomponent fibers of Examples 16, 27 and 29 are ethylene diamine tetra acetic acid from Sigma-Aldrich Company, Atlanta, Georgia, USA Tetra sodium salt (Na ₄ EDTA) is washed separately at 80 ° C. using soft water containing about 1% by weight based on the weight of the bicomponent fiber to remove the water dispersible sulfopolyester “sea” component, whereby the bicomponent fiber Polyester microfiber, which was the "island" component of the polymer, was released. Adding one or more water softening agents such as Na ₄ EDTA aids in the removal of the water dispersible sulfopolyester polymer from the bicomponent fibers. The washed polyester microfibers were washed with soft water at 25 ° C. to essentially remove most of the “sea” components. The washed polyester microfibers were observed with an optical microscope to show excellent release and separation of the polyester microfibers. The use of a water softening agent such as Na ₄ EDTA in water prevents Ca ⁺⁺ ion exchange of the sulfopolyester, which can adversely affect the water dispersibility of the sulfopolyester. Typical soft water can contain a Ca ⁺⁺ ion concentration of 15 ppm or less. The soft water used in the process described herein has an essentially zero concentration of Ca ⁺⁺ and other polyvalent ions, or alternatively uses a sufficient amount of water softening agent such as Na ₄ EDTA that binds this Ca ++ ion and other polyvalent ions. It is desirable to do. This polyester microfiber can be used to make wet-laminated sheets using the procedures of the above-described examples.

Example 35

The short-cut length island-in-sea bicomponent fibers of Examples 16 and 27 were treated separately using the following procedure. 17 grams of pre-gelatinized quaternary cationic potato starch, Solvitose N, manufactured by Abbe, Foxhall, The Netherlands, was added to the distilled water. After starch was completely dissolved or hydrolyzed, a fiber slurry was prepared by slowly adding bi-component fibers of 429 grams of short-cut length to the distilled water. The Williams Rotary Continuous Feed Refiner (5 inch diameter) was turned on to purify or mix the fiber slurry to provide sufficient shearing action for the water-dispersible sulfopolyester to separate from the polyester microfibers. The contents of the raw chest were poured into a 24-liter stainless steel container, and the lid was tightly closed. A stainless steel container was placed on a propane cooker and heated until the fiber slurry began to boil at about 97 ° C. to remove the sulfopolyester component in the fiber, and release the polyester microfibers. After the fiber slurry reached the boiling point, it was shaken with a manual shaking paddle. The contents of the stainless steel container were poured into a 27in x 15in x 6in deep Falls Bottom Knuche with a 30 mesh screen to prepare sulfopolyester dispersions and polyester microfibers. The sulfopolyester dispersion consisted of water and water dispersible sulfopolyester. The polyester microfibers were washed in Knuche for 15 seconds with 10 liters of soft water at 17 ° C. and squeezed to remove excess water.

20 grams of polyester microfiber (based on dry fiber) was added to 2000 ml of water at 70 ° C. and using a 2 liter 3000 rpm 3/4 hp hydropulper manufactured by Herman Manufacturing Company It was shaken for 3 minutes (9,000 revolutions) to prepare a 1% concentration microfiber slurry. A handsheet was prepared using the procedure described above in Example 20.

The handsheet was observed with an optical microscope and a scanning electron microscope to show excellent separation and formation of polyester microfibers.

Example 36

This example was a bicomponent extruded in a manner to form 4.5 denier / filament fibers (each filament having a sea fraction comprising 37 PET islands containing Eastman F-61HC polyester and Eastman sulfopolyester polymer). It relates to the opening of sea-island (INS) fibers. The ratio of polyester component to sulfopolyester sea component was 70PET / 30 sulfopolyester. The fibers were made using a bicomponent spin pack, manufactured by Hills Inc. (Melbourne, Florida). Extrusion and stretching conditions were adjusted to achieve a nominal 22 micron total starting fiber targeting individual islands with an average diameter of 2.0 microns. Stretched yarn was prepared and cut into 1.5 mm long staple fibers. The bicomponent fiber was cut to a total length of 1.5 mm to produce a cut bicomponent fiber, which was used in the evaluation to produce an open microfiber comprising individual 3.0 micron individual PET islands after the opening process.

Bicomponent fibers comprising 37 INS filaments cut to 1.5 mm long were opened by a batch opening process to remove the sulfopolyester sea component, a binder that holds the 37 PET islands together in the cut bicomponent fibers. In the opening process of Example 36, a 20 kg load of deionized water was added to a 10 gallon laboratory hydropulping machine (Adirondack Machinery Co.), and low pressure steam was added while stirring at a 30% speed setpoint. Heated to ° C. When the deionized water reached 79 ° C, 400 g of 37 INS chopped bicomponent fibers were quickly added to the stirred water, and all of the chopped bicomponent fibers were added, and then the timer was started. After 10 seconds of stirring, a sample of 400 cc of open microfiber slurry is recovered and immediately screened using a collander to contain the sulfopolyester polymer (which is removed during a 10 second contact in 79 ° C. water). The microfiber product was quickly separated from the first mother liquor. The microfiber product sample was pressed against the screen to dehydrate the microfiber product to a moisture content of about 20-25%. After 20 seconds mixing time, 60 seconds mixing time, and 120 seconds mixing time, samples were recovered from the hydropulping machine, and each sample was similarly screened to recover the first mother liquor separated from the microfiber product.

The degree of removal of the sulfopolyester sea component was evaluated by measuring the solids content of the first mother liquor recovered from each of the four test samples. In this process, the percent solid level of the final sample taken after a long 120 second contact time represents the condition in which the largest amount of sulfopolyester is removed from the starting cut bicomponent fiber with almost quantitative removal. The solids content of each sample was determined by measuring the weight (+/- 0.001 g) of a 3 inch x 5 inch aluminum pan and then adding 100.0 g of a first mother liquor sample containing the removed sulfopolyester. Water was boiled off using a hot plate at medium speed to prevent the liquid from bumping out of the pan. After removing almost all the water on the hot plate, a sample pan containing the polymer residue is added to a uniform moisture content by placing the pan in a forced air oven at 180 ° C. for 5 minutes to adjust the residue to a uniform moisture content. And dried. The pan was weighed again (+/- 0.001 g), and the weight of the residue was calculated by subtracting the starting pan weight. The solids content was calculated by dividing the residue weight by the starting sample weight.

The change in solids in the first mother liquor recovered from the opening process of Example 36 is shown in FIG. 8.

After quantitatively removing the sulfopolyester polymer from the cut multicomponent fiber, the solid residue in the first mother liquor will not increase. The test results showed that the solid content of the recovered first mother liquor was minimal after the first 10 second sample was recovered. The difference in solid level of the samples recovered at 20 seconds, 60 seconds, and 120 seconds is within the test error range. The removal efficiency after contacting only 10 seconds in 79 ° C. water was 95% or within 5% of the quantitatively considered removal level. In Example 36, the sulfopolyester sea component was effectively removed from 4.5 dpf of 37 INS cut bicomponent fibers using a contact time of 15 seconds or less in water stirred at 79 ° C.

Example 37

The process of Example 36 was repeated by increasing the speed setting of the Adirondack hydropulping machine from 30% to 80% to improve mixing of 37 INS cut bicomponent fibers in deionized water heated to 79 ° C. . A sulfopolyester removal profile similar to FIG. 1 was observed, where the solid% value of the initial 10 second sample was within the test accuracy of the later solid value, indicating a quantitative sulfopolyester removal rate after a 10 second contact time at 79 ° C.

Example 38

The 37 INS bicomponent fiber opening process was changed in the same manner as in Example 36 by changing the temperature of the deionized water contacting the cut bicomponent fiber to a temperature of 74 ° C. or 5 ° C. lower than the temperature used in Example 36. Was carried out.

The results are shown in FIG. 9.

Samples recovered at 20 seconds, 60 seconds, and 120 seconds showed solid content consistent with quantitative removal of sulfopolyester from the cut bicomponent fibers. Even when contacted in water at 74 ° C for 10 seconds, sulfopolyester removal was within 5% of quantitative removal, indicating that sea component was quickly removed from the cut bicomponent fiber at 74 ° C.

Example 39

The cut bicomponent fiber of Example 36 with 37 INS configuration and 4.5 dpf fineness was opened in a similar manner as described in Example 36, with agitation of the hydropulping machine set to 50% setpoint and opening step The temperature of deionized water used in was reduced to 68 ° C. Samples were recovered after processing the bicomponent fibers cut at a stirred 68 ° C. temperature for 15 seconds, 30 seconds, 60 seconds, and 120 seconds. For the first mother liquor recovered from each sample, the sulfopolyester content was analyzed by measuring the solids content using the method described in Example 36. The sulfopolyester content in the first mother liquor is shown in Figure 10 as a function of treatment time. The time required for the solid level to reach the asymptote (the sulfopolyester removal approaches the quantitative level) is an indicator of the speed of the open phase.

At 68 ° C., quantitative removal of the sulfopolyester sea component was achieved after 60 seconds or more contact time in 68 ° C. water, but removal after a short time (15 seconds) was far from quantitative removal, and only 30 seconds later, quantitative removal was approached. Did. By comparison, Examples 36-38 showed nearly quantitative sulfopolyester sea component removal in samples taken after a contact time of 10 seconds (at this time, the water temperature in these samples was higher than in Example 39). Example 39 shows that when a longer fiber / hot water contact time of 60 seconds or more at 68 ° C. is applied, the bicomponent fiber opening process is more effective but sea components are incompletely removed at shorter treatment times.

Comparative Example 40

The bicomponent fiber opening process was performed in the same manner as in Example 36, but the temperature of deionized water used during the opening process was further reduced to 63 ° C. Samples were recovered after 15 seconds, 30 seconds, 60 seconds, and 120 seconds, and the amount and open efficiency of the sulfopolyester removed were determined by analyzing the solid components of the first mother liquor recovered from each sample. The rate of sulfopolyester removal is shown in FIG. 11. The results in FIG. 11 show the slower removal behavior of the sulfopolyester sea component.

About 2/3 of the sulfopolyester sea component was removed from the cut bicomponent fiber after 15 seconds contact time, and about 85% after 30 seconds contact. The removal level at the 60 second contact time was high but not quantitative. At 63 ° C., an open time of more than 2 minutes was required to remove sea components from the cut bicomponent fibers to a quantitatively considered removal level. The main effect of the open process is to remove the sea component to a level that is considered quantitative, and in this regard, the slow removal rate measured in Comparative Example 40, on a commercial scale, is cut with sulfopolyester as a removable component. It showed that it is a slower opening condition in opening the bicomponent fiber. In Comparative Example 40, the agitation setpoint was 30%, a higher agitation or turbulence level during the opening process could reduce the time required to perform quantitative opening, and a reduction in mixing energy could slow the opening process and sulfopolyester Much longer time may be required to completely remove the ingredients.

The removal rates described in this example and all previous examples are based on cut bicomponent fibers comprising sulfopolyester as a removable component. If the removable component is replaced with a polymer type that can be more easily or more difficult to remove (dissolve or emulsify) into the water phase, the open temperature will vary depending on the nature of the removable polymer. These examples have been provided to demonstrate the removal properties of bicomponent fibers containing certain types of removable sulfopolyester polymers, but they are, in terms of open conditions suitable for bicomponent fibers comprising other types of removable polymers. It does not mean that it is limited.

Comparative Example 41

In Comparative Example 41, the same process as described in Example 36 was used, but sufficient CaCl ₂ was added to the deionized water load, Ca ^{+ 2} cations were added to the water phase at a level of 20 ppm by weight, and the temperature of the open process was 77 ° C. The sulfopolyester removal profile for fiber opening under these conditions is shown in FIG. 12.

When compared to Examples 36 and 37 performed using deionized water at similar open temperatures, the sulfopolyester removal rate in Comparative Example 41 was much slower. In the previous two examples, almost quantitative sulfopolyester removal was recorded after a contact time of about 10 seconds in deionized water at 79 ° C. In Comparative Example 41, removal of only about 90% was achieved after 30 seconds with a similar agitation level.

Compared to the removal properties in Examples 36, 37 and 38, the sulfopolyester removal properties in Comparative Example 41 were slower, whereas in Comparative Example 41 only about 90% of removal was measured after 30 seconds, whereas the previous practice In examples, almost quantitative removal was measured after 10-15 seconds. The removal properties of Comparative Example 41 were similar to those measured for Comparative Example 40 (FIG. 11) using deionized water, which was carried out at a lower opening temperature of 14 ° C. but did not have light cations. Comparative Example 41, the water hardness used for the opening process, been provided to illustrate dropped below a significant effect on contact time and temperature required to open the two-component fiber comprising a water-dispersible sulfopolyester component of 20ppm Ca ^{+ 2} Hardness is the boundary and higher levels may make full fiber opening slower or impossible.

Example 42

continuity Binary  Fiber opening process

The previous Examples 36-39 illustrate the use of a batch type open process to remove water-dispersible polymer fractions from bicomponent fibers. In commercial manufacturing, continuous type processes are generally used because continuous operation provides higher efficiency. The major improvement in efficiency is due to the batch loading of the entire batch cycle and omission of the batch ejection step (which eliminates significant process time during the batch cycle and also allows the same production to be achieved using smaller machine sizes).

There are two main types of continuous operations applicable to the open process of bicomponent fibers consisting of removing or extracting the water dispersible polymer from the water non-dispersible polymer fiber material to the aqueous phase. The first type of process removes the open microfiber slurry from the stirred tank at the same mass flow rate while adding water and cut multi-component fibers to the stirred tank at a constant rate and constant feed rate in the stirred tank. It is a continuous stirred tank reactor (CSTR) capable of maintaining a constant level of the cut multi-component fiber slurry.

The disadvantage of CSTR is the residence time distribution of the cut multicomponent fibers inside the stirred tank during the process. In a batch type process, all products are processed for a nominal equal amount of time during the batch cycle between the end of the load phase and the start of the discharge phase. In CSTR, the chopped multi-component fibers applied to the stirred tank are mixed with the material treated for various lengths of time in the tank, and the material discharged from the tank contains microfibers treated inside the tank for various lengths of time. The amount of time the microfibers stay inside the tank during the CSTR opening process is defined by the statistical average, and the central point of the statistical average is the average time that the microfiber material stays inside the tank. This statistical average residence time (RT) in which the microfibers stay inside the stirred tank is defined by the equation RT = V _t / Q, where V _t is the total volume of liquid contained in the stirred tank, and Q is continuous This is the volume of liquid that leaves the tank during operation.

The problem with the CSTR for continuous operation is that, based on this statistical distribution, a portion of the cut multicomponent fibers applied to the tank stays inside only for a short period of time (which may be insufficient for full fiber opening), and this distribution At the other end of the cut, a portion of the cut multicomponent fiber is placed in the tank for much longer than the target average RT (during this time microfibers of small diameter can be mechanically damaged by excessive mixing over a long period inside the tank). Is to stay.

For this reason, another method for the continuous fiber opening process is the plug flow process commonly used for chemical treatment. In this type of process, a fluid is applied to a process vessel at a constant rate, and each element of the fluid applied to the vessel moves through the vessel at a nominally constant rate such that all elements of the fluid are inside the vessel for a nominally equal amount of time. It should be contained in. Compared to CSTR, the plug flow opening process has problems associated with cut multicomponent fiber parts that stay inside the process vessel for an insufficient time to fully open, and fiber parts that stay in the tank for an excessive amount of time causing mechanical damage to the microfibers. Can be omitted.

In one embodiment of the plug flow opening process for bicomponent fibers, the plug flow vessel can be a long pipe section, where a hot aqueous multicomponent fiber slurry is applied at one end of the pipe section at a constant volumetric flow rate and multicomponent After the fiber slurry passes the pipe at a nominal constant flow rate and the residence time inside the pipe (defined as the total volume contained within the process pipe divided by the volume flow rate of the multicomponent fiber slurry entering the process pipe) The multicomponent fiber slurry exits the other end of the process pipe.

Typical plug flow Binary  Fiber opening process

Several examples of a continuous plug flow process for opening a cut multi-component fiber comprising a water-dispersible sulfopolyester phase (which is removed from the cut multi-component fiber during the opening process) are provided. Certain process steps in the overall plug flow operation can fall into the following categories:

1) A process for preparing a concentrated cold cut multicomponent fiber slurry from cut multicomponent fibers,

2) the process of preparing a hot treated aqueous stream for mixing with a cold cut multicomponent fiber slurry,

3) Combination process of streams (1) and (2) to produce a hot multi-component fiber slurry,

4) a process for producing an open microfiber slurry by opening the fiber as the hot multicomponent fiber slurry 3 flows through the process pipe as a plug flow, and

5) The process of separating the microfiber product stream from the open microfiber slurry containing the sulfopolyester polymer removed using a screen filtration device.

A more detailed description of each of these specific process steps is provided below.

1) Preparation of cold cut multicomponent fiber slurry from cut multicomponent fibers

Tap water containing a nominal 25 ppm light cation was passed through a water softener to reduce the concentration of the light cation to less than 1 ppm. Soft water at about 18 ° C. was metered continuously into a stirred tank containing 10 gallons of fluid level, at a target flow rate to maintain a constant fluid level in the stirred tank. The cut multi-component fibers of Example 36 were continuously added to the well-stirred mixture tank at a constant rate and rate relative to the flow of the stream to produce a cold cut multi-component fiber slurry containing the cut multi-component fibers at a target concentration. . To pump the cold cut multi-component fiber slurry of the cut multi-component fibers out of the cold slurry mixture tank, using a variable speed centrifugal pump to pump the cold cut multi-component fiber slurry, The pump was pumped at the same rate as the ingredients were fed into the mixture tank to maintain a constant level at.

The principle of operation of the cold slurry process step is to ensure that the agitation provided is sufficient to prevent the chopped multicomponent fibers from settling in the mixture tank while keeping the chopped multicomponent fibers suspended. It is to disperse the cut multi-component fiber into cold water containing low concentration. Both water temperature and residence time in the cold slurry tank of the cut multicomponent fiber are designed to prevent significant sulfopolyester removal in the cold slurry tank and minimize mechanical damage to the fibers in the tank.

2) Preparation of a hot treated aqueous stream for the fiber opening process

Deionized water was metered into the injector of a steam heated tubular heat exchanger using a micro-adjustable flow controller to maintain a constant hot water flow at the target rate. Steam was applied to the heat exchanger to heat the deionized water stream to the outlet temperature of 96-98 ° C at the target flow rate. The hot deionized water from the heat exchanger was sent to a mixing tee to combine with the cold cut multicomponent fiber slurry stream described above.

3) Combination of hot water stream and cold fiber slurry stream

The hot water stream (2) and the cold cut multi-component fiber slurry stream (1) are continuously combined using only turbulent flow to homogeneously mix the two streams and the combined stream is opened to the fiber outside the mixing tee (1 1/2 The two streams were combined in a 1 1/2 inch pipe tee by continuously flowing on an inch schedule consisting of 40 CPVC pipes. The ratio of hot water (98 ° C.) to cold cut multi-component fiber slurry (18 ° C.), because the temperature of the combined stream causes rapid opening or removal of the sulfopolyester polymer from the cut multi-component fiber. It was chosen to be high enough. The target temperature for the combined stream was in the nominal 70-80 ° C. range, allowing the sulfopolyester to flow rapidly through a 1 1/2 inch pipe opening.

4) Fiber opening in plug flow through 1 1/2 inch pipe arrangement

The opening device consisted of five 10-foot sections of a 1 1 / 2-inch CPVC pipe, with a total length of 55 feet from the inlet to the outlet. An internal pipe volume of 0.78 ft ³ was calculated. The typical flow rate of the combined fiber slurry stream is about 1.1 ft ³ / min, which is the combined fiber slurry flowing through the plug flow opening device, corresponding to a nominal residence time of 40 seconds.

An example is provided where the length of the plug flow pipe section is extended to a total length of 110 feet to obtain a total residence time of 80 seconds during the fiber opening step.

5) Open microfiber recovery

Baskets 18 inches in diameter and 12 inches high were made of perforated steel sheet metal with 3/16 inch perforations. The pores are small enough so that the microfiber product leaving the open stage does not pass and the process water is drained. The effluent from the 1 1/2 inch pipe opening device is sent directly to the basket, allowing the first mother liquor containing sulfopolyester to be drained and to recover the wet cake comprising the open PET microfibers.

By applying the general plug flow bicomponent fiber opening process described above to the cut bicomponent fiber of Example 36, continuous opening of the 37 degree bicomponent fiber was performed. In this example, the crude tap water at 18 ° C. is passed through a soft water unit to remove light cations to less than 1 ppm and the soft water is about 2.3 gallons in a stirred tank holding pre-treated water at a nominal 12 gallon liquid level. Cold cut bicomponent fiber slurries were produced by metering in at min / gpm or nominal 9 kg / min. When cold water was applied to the tank, a variable-speed centrifugal pump with a 4-inch impeller was used to pump from the base of the tank to the mixing tee and open-stage plug flow pipe section, in order to maintain a constant tank level. The speed of the pump was adjusted so that liquid was pumped out of the tank at a nominal 2.3 gpm rate as when added.

When water is added to the tank, the 37 INS cut bicomponent fibers of Example 36 are continuously added to the liquid in the mixing tank through a port at the top of the tank at a rate of 325 g / min while sufficient stirring of the bicomponent fiber slurry in the tank. It was applied so that the starting cut bicomponent fibers were kept in suspension inside the tank and sedimentation was prevented. The concentration of the cut multicomponent fibers in the cold multicomponent fiber slurry during continuous operation reached a steady state slurry concentration of about 3.5% by weight fiber in water.

The hot water stream for the process of Example 42 was created using a Pic heater device, where it was dewatered at a nominal rate of 6 gpm or 22 kg / min to the inlet of a steam-heated heat exchanger via a micro-adjustable flow control device. Ionized water was introduced. The outlet temperature of the deionized water leaving the heat exchanger was adjusted to 97 ° C by a temperature controller that regulates the steam pressure against the jacket of the heat exchanger to control the outlet temperature.

The hot water stream exiting the Pic heater flows into the inlet of the mixing tee where it merges with the flow stream from the cold bicomponent fiber slurry tank and then passes through a plug flow contactor. The combined total flow of the hot water stream and the cold bicomponent fiber slurry stream was 8.3 gpm or 31 kg / min. The hot water stream accounted for about 71% by weight of the combined stream. The temperature of the combined stream exiting the mixing tee was measured at 75 ° C., and the outlet temperature was controlled by the individual temperature of each stream and the relative proportion of streams combined in the mixing tee. Likewise, the concentration of cut bicomponent fibers in the combined stream was reduced from 3.5% in the cold slurry to 1.0% in the combined stream, based on the proportion of each individual stream before mixing.

The combined fiber slurry stream containing 1.0% by weight of cut bicomponent fibers at a temperature of 75 ° C. was sent to the inlet of a plug flow opening device. The plug flow opening device consisted of five compartments of 1 1/2 inch schedule 40 CPVC pipe with a total flow length of 55 feet. The average plug flow rate through which the cut bicomponent fiber slurry passed through the pipe section was calculated to be 1.2 ft / sec, and the average residence time of the cut bicomponent fiber slurry in the plug flow section was 45 under the flow conditions applied in Example 42. It was calculated to be seconds. Calculation of the Reynolds number for the pipe flow under these conditions means that the mixed energy obtained by the turbulence flows in a turbulent manner to help the sulfopolyester polymer be removed from the cut bicomponent fiber to create an open microfiber slurry. It was determined if it exists. The process requirement of this example was essentially quantitatively removing sulfopolyester from the bicomponent precursor fibers within a 45 second contact time inside the pipe zone.

The microfiber was filtered from the open microfiber slurry exiting the plug flow contact zone using a basket filter with 3/16 inch perforation (40% of surface area). Compared to the microfibers of Examples 36-38, the microfibers of Example 42 filtered less effectively in terms of fine fibers passing through the filter and slower permeation rates. This result was attributed to the less entanglement of the microfibers while flowing in the plug flow zone of Example 42. Turbulent mixing in Example 42 can cause the microfibers to deform and entangle to a lesser degree than vigorous agitation in the previous example, and the microfibers of Example 42 may require a dewatering screen with smaller openings.

The texture of the microfibers of Example 42 changed dramatically in the texture of the starting 1.5 mm cut bicomponent fiber. The texture of the starting wet cut bicomponent fiber was very rough and sandy. The texture of the filtered microfiber of Example 42 was smooth to the extent that it was sticky, indicating that the fiber properties were dramatically changed.

The microfibers of Example 42 were redispersed in additional water and slightly diluted to apply to microscope slides for characterization. Microscopic examination confirmed that the microfibers of Example 42 were very fine fibers with a nominal fiber diameter of about 3 microns (which corresponds to the starting diameter of the starting PET island domain in the 37-island cut bicomponent fiber).

Microscopic examination confirmed the evidence that there were few residual sea materials binding the 3 micron island fibers together in the resulting fibers. Incompletely open fibers comprising several island fibrils bound together by residual sea material that were incompletely removed during the process of Example 42 showed only a small fraction.

The microfibers of Example 42 were re-dispersed in water to the filtered microfiber product to a solid fiber concentration of 0.02% in water and converted to this diluted fiber solution into a paper hand sheet sample using a standard 6.25 inch diameter TAPPI sheet forming apparatus. Was evaluated. Comparative tests were performed using microfibers opened with the batch opening process described in Examples 36-38. The microfibers of Example 42 were converted to paper-like products by high dilution formation techniques using conventional 6.25 inch diameter TAPPI sheet forming apparatus and process properties when redispersed into low water solid slurry and redispersed. Both in terms of sheet properties when preformed were found to be qualitatively equivalent to the fibers opened by the batch process.

Example 43

In Example 43, the process of Example 42 was performed, but the rate of addition of chopped bicomponent fibers to the cold slurry tank was increased from 325 g / min to 475 g / min, which increased the solids level in the cold slurry stream to 3.5. Corresponds to an increase from 5.0% by weight. The nominal concentration of the cut bicomponent fibers in the hot slurry entering the plug flow pipe section was 1.5% by weight. The increased cut bicomponent fiber levels in both the cold slurry zone and the combined hot slurry zone did not cause any noticeable process difficulties compared to the process of Example 42.

The microfibers of Example 43 were subjected to characterization in the same manner as described in Example 42, and when redispersed with a dilute fiber slurry and converted to sheet samples by conventional high-dilution paper formation techniques, the degree of openness. And functionally equivalent in terms of subsequent behavior.

Example 44

In Example 44, the process of Example 42 was performed, but the flow of cold water for the cold slurry tank was reduced from 2.3 gpm to about 2.0 gpm, and the flow of 97 ° C. water from the Pic heater to the mixing tee from 6.0 gpm to 7.2 gpm. Increased. By providing a change in the ratio of the hot water stream to the cold water stream, the temperature of the combined stream was increased from 75 ° C in Example 42 to 80 ° C in Example 44. The chopped bicomponent fibers were added to a cold slurry tank at about 320 g / min, which corresponded to 4.0 wt% of the chopped bicomponent fiber concentration in the cold bicomponent fiber slurry stream. After the merging process, the concentration of cut bicomponent fibers in the combined stream exiting the mixed tee was 0.90% by weight.

The microfibers of Example 44 compared to the microfibers of Examples 42 and 43, due to the higher degree of entanglement in the flow through the 1 1/2 inch pipe at the higher temperature of Example 44 compared to Examples 42 and 43, Filtered better. Microscopic examination of the microfibers of Example 44 showed that the microfibers consisted of microfibrils with a nominal 3 micron diameter (which corresponds to the starting diameter of the island domains in the truncated bicomponent fiber).

The microfibers of Example 44 were redispersed in water at high dilution in the manner described in Example 42 and converted to sheet samples. The properties of the microfibers of Example 44 were found to be qualitatively equivalent to those of the microfibers of Example 42 opened at a lower temperature with the same plug flow opening process.

Example 45

The process of Example 44 was repeated but the length of the 1 1/2 inch plug flow pipe section used for contacting the cut bicomponent fiber with hot water was increased to 110 feet. In the process of Example 45, the effective residence time of the combined bicomponent fiber slurry at 80 ° C was doubled to about 90 seconds. Filtration of the microfibers was very effective and similar to the behavior identified in Example 44. Microscopic examination of the microfibers of Example 45 showed that these microfibers were essentially completely open and consisted of individual microfibrils with a nominal 3 micron diameter. The results of the high magnification dilution sheet formation test of the product of Example 45 in the same manner as in Example 44 did not show any characteristic difference in behavior.

In Example 45, increasing the residence time in the plug flow pipe section of the devices used in Examples 42-45 did not show a significant improvement over the less residence times used in Examples 42-44. The residence time of 45 seconds in these examples was sufficient to remove the sulfopolyester sea polymer to a degree sufficient to cause opening of the cut bicomponent fibers because of the high temperature used during the opening process of Examples 42-44. The use of longer plug flow contact times as practiced in Example 45, provided that process advantages are implemented to perform the open process at the lowest possible temperature required to effectively remove the water dispersible sulfopolyester polymer from the cut bicomponent fibers, these It can provide a greater advantage than shown in the examples.

Claims (20)

(A) contacting the cut multi-component fibers having a length of less than 25 mm in a fiber slurry zone with a treated aqueous stream to produce a cut multi-component fiber slurry, wherein the cut multi-component fibers have one or more water dispersibility A sulfopolyester and at least one water non-dispersible synthetic polymer immiscible with the water dispersible sulfopolyester, wherein the treated aqueous stream is at a temperature of 40 ° C. or lower;
(B) contacting the cut multicomponent fiber slurry with a heated aqueous stream in a mixing zone to produce a heated multicomponent fiber slurry;
(C) sending the heated multi-component fiber slurry to the fiber open zone to produce a microfiber slurry opened at a temperature in the range of 55 ° C to 100 ° C by mixing sufficient to remove a portion of the water dispersible sulfopolyester. As a step, the weight percent of solids in the open microfiber slurry ranges from 0.1% to 20% by weight, the water non-dispersible polymer microfibers having a minimum transverse dimension of less than 10 microns;
(D) sending the open microfiber slurry to a first solid-liquid separation zone to produce a microfiber product stream and a first mother liquor stream, wherein the first mother liquor stream comprises water and a water dispersible sulfopolyester. , step; And
(E) sending at least a portion of the first mother liquor stream to a second solid-liquid separation zone to produce a second wet cake stream and a second mother liquor stream, wherein the second mother liquor stream contains water and water-dispersible sulfopolyester. And wherein the second wet cake stream comprises microfibers
A method of producing a microfiber product stream comprising a. delete According to claim 1,
The method, wherein the cut multicomponent fiber has a length of less than 5 mm. According to claim 1,
The heated aqueous stream comprises a treated aqueous stream generated by sending an untreated aqueous stream to an aqueous treatment zone,
The treated aqueous stream contains less than 50 ppm divalent and polyvalent cations,
And sending the treated aqueous stream to a heat exchanger zone to produce a heated aqueous stream. According to claim 1,
In the fiber slurry zone, the method, wherein the weight percent of the cut multicomponent fibers in the cut multicomponent fiber slurry ranges from 35% to 1% by weight. According to claim 1,
The fiber slurry zone comprises one or more pieces of equipment selected from the group consisting of a hydro-pulper, a continuously stirred tank reactor, and an agitated batch tank, Way. According to claim 1,
The mixing zone comprises a continuous stirred tank reactor, a stirred batch tank and one or more equipment selected from the group consisting of pipes. According to claim 1,
The method in which the heated multicomponent fiber slurry in the mixing zone has chopped multicomponent fibers in the range of 10% to 1% by weight. According to claim 1,
Wherein the fiber opening zone comprises one or more equipment selected from the group consisting of a mixing tank, a stirred batch tank, a plug flow reactor, a pipe, and a continuously stirred tank reactor. According to claim 1,
The method, wherein the temperature of the open microfiber slurry in the fiber opening zone ranges from 55 ° C to 100 ° C. delete According to claim 1,
The first solid-liquid separation zone, perforated basket centrifuge, continuous vacuum belt filter, batch vacuum nutschfilter, batch perforated sedimentation tank, twin wire dewatering device, continuous horizontal with compression area A method comprising one or more equipment selected from the group consisting of a belt filter, a non-vibration inclined screen device equipped with a wedge wire filter medium, a continuous vacuum drum filter, and a dewatering conveyor belt. According to claim 1,
The method, wherein the weight percent of solids in the microfiber product stream ranges from 10% to 65% by weight. According to claim 1,
At least a portion of the first mother liquor stream
(a) the fiber slurry zone,
(b) the mixing zone,
(c) the fiber open band,
(d) a heat exchange zone to produce the heated aqueous stream, wherein at least a portion of the heated aqueous stream is sent to the fiber open zone and / or the mixing zone, and / or
(e) the first solid-liquid separation zone
How to include additional sending.
delete According to claim 1,
And further comprising sending at least a portion of the second mother liquor stream to a first concentration zone to produce a first polymer concentrate stream and a first recovered water stream. According to claim 1,
At least a portion of the second mother liquor stream
(a) the fiber slurry zone,
(b) the mixing zone,
(c) the fiber open band,
(d) a heat exchange zone to produce the heated aqueous stream, wherein at least a portion of the heated aqueous stream is sent to the fiber open zone and / or the mixing zone, and / or
(e) as a washing stream, said first solid-liquid separation zone
How to include additional sending. The method of claim 16,
And further comprising purging the first mother liquor stream, the second mother liquor stream and / or the first recovered water stream from the method for reuse or to a waste water treatment system. The method of claim 16,
The first recovered water stream
(a) the fiber slurry zone,
(b) the mixing zone,
(c) the fiber open band,
(d) a heat exchange zone to produce the heated aqueous stream, wherein at least a portion of the heated aqueous stream is sent to the fiber open zone and / or the mixing zone, and / or
(e) as a washing stream, said first solid-liquid separation zone
How to include additional sending. The method of claim 16,
And further comprising sending at least a portion of the first polymer concentrate stream to a second concentration zone to produce a vapor stream and a molten polymer stream.

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