JP2008200424A - Manufacturing method of ultrafine nonwoven fabric for wiping cloth and ultrafine nonwoven fabric for wiping cloth - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for improving fiber fineness and a segmentation rate, and an ultrafine nonwoven fabric for wiping clothes, which has an excellent wiping property, in a manufacturing method of the ultrafine nonwoven fabric for wiping clothes by segmenting the segmenting, splittable composite fiber consisting of two components of polyamide and polyester. <P>SOLUTION: This manufacturing method of the ultrafine nonwoven fabric for wiping clothes for segmenting the segmenting, splittable composite fiber consisting of polyamide based polymer and polyester based polymer and having a single yarn fineness of 0.01-0.30 dtex, contains polyalkylene glycol of 0.3-3.0 wt.% and organic metal salt expressed by R-SO<SB>3</SB>M of 0.5-3.0 wt.% at least in either one of the polymers, forming it into a nonwoven fabric, segmenting it under the presence of water and providing the ultrafine nonwoven fabric for wiping clothes, which has micro fineness and a high segmentation rate and consisting of polyamide and polyester. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrafine nonwoven fabric for wiping cloth, in which a release split composite fiber composed of a polyamide polymer and a polyester polymer is a nonwoven fabric, and the release split composite fiber is split.

  Conventionally, ultrafine fiber nonwoven fabrics have been used in various fields such as life-related materials and clothing, and many types have been proposed.

In wiping cloth, which is one of the applications of ultrafine fiber nonwoven fabrics, the surface area of the fibers that make it up is expanded to achieve higher wiping performance, that is, higher wiping efficiency and more wiping performance of fine dirt and dust. There is a need for improvement. As a means of increasing the surface area, the thinner the fiber, the larger the specific surface area per single yarn fineness in inverse proportion to the half power of the single yarn fineness. A fiber nonwoven fabric is preferred. As a method for reducing the fineness, there have been proposed a method for obtaining a fineness by direct spinning and drawing, a method for generating ultrafine fibers by dividing and solvent-treating fibers capable of generating ultrafine fibers in a subsequent process, and the like.
However, in the direct spinning drawing method, the fineness of the single yarn is limited to about 0.3 dtex, and it is technically difficult to produce a fine fiber finer than this.

As another method, a sea component of a sea-island type composite fiber composed of a plurality of types of polymer is eluted and removed, and the island component is made ultrafine, or a two-component alternating laminating and separating split type composite fiber (hereinafter referred to as “component”). There is a method of producing a nonwoven fabric by applying a mechanical external force to the separated split type composite fiber) and dividing it into ultrafine fibers.
In particular, the method of making ultra-fine fibers from a long-fiber nonwoven fabric obtained by combining exfoliated split-type composite fibers with the spunbond method without eluting one polymer component is also excellent in terms of energy costs and environmental considerations. It is a method.

The present inventors have proposed a wiping cloth excellent in wiping property obtained by dividing and thinning a separation-dividing composite long-fiber nonwoven fabric composed of two components of polyamide and polyester in Japanese Patent Application Laid-Open No. 2004-8501. Although it is useful to take advantage of the water absorption and flexibility properties of polyamide and the strength properties of polyester, the wiping property is not sufficient. In order to improve the wiping property, it is necessary to further reduce the fineness and the division rate. At present, there is a problem that the division rate decreases if the fineness is reduced, and a method for further improving the division property has been demanded. .
JP 2004-8501 A

  The present invention has been made against the background of the above-described prior art, and the object thereof is a method for improving the division ratio in the fineness of an ultrafine fiber nonwoven fabric composed of two components of polyamide and polyester, and an ultrafine wiping cloth excellent in wiping performance. It is to provide a non-woven fabric.

As a result of intensive studies to solve the above-mentioned problems, the present inventors, as a result, have a separation split type in which the single yarn fineness after split consisting of a polyamide polymer and a polyester polymer is 0.01 to 0.30 dtex. Composed of a composite fiber nonwoven fabric, and at least one polymer, 0.3 to 3.0% by weight of a polyalkylene glycol and 0.5 to 3.0% by weight of an organometallic salt represented by RSO ₃ M It was made to contain, and after making it into a nonwoven fabric, it was subjected to a division treatment in the presence of water, thereby obtaining an ultrafine nonwoven fabric for wiping cloth made of polyamide and polyester having a high division ratio.

According to the present invention, when the exfoliated split type composite fiber nonwoven fabric composed of a polyamide polymer and a polyester polymer is divided and made fine, at least one component of the fiber component is represented by RSO ₃ M together with polyalkylene glycols. By containing a specific amount of an organic metal salt, the water swelling of polyalkylene glycol is synergistically promoted in the presence of water, and the single yarn fineness after separation is divided into fine fineness of 0.01 to 0.30 dtex. Improves. As a result, it is possible to obtain an ultrafine nonwoven fabric for wiping cloth having a fineness and a high division ratio and good wiping property.

Hereinafter, embodiments of the present invention will be described in detail.
The ultra-fine nonwoven fabric for wiping cloth of the present invention is obtained by forming a separation-dividing composite fiber as a nonwoven fabric and then performing a division treatment.

  There are two methods for making a nonwoven fabric: a card after stripping the split split composite fiber, a method of needle punching to make a nonwoven fabric, and a method of making the split split composite fiber a spunbond nonwoven fabric and a long fiber nonwoven fabric. This method is also possible, but from the viewpoint of productivity, a method using a long-fiber nonwoven fabric is preferred.

  The release-dividing composite fiber in the present invention is not particularly limited as long as it is composed of a fiber-forming polyester polymer and a fiber-forming polyamide-based polymer and can be separated into each component by mechanical treatment or the like. Examples of the polyamide polymer preferably used include nylon-6, nylon-66, nylon-610, nylon-11, nylon-12 and the like. On the other hand, examples of the polyester-based polymer include polyethylene terephthalate, polytriethylene terephthalate, polybutylene terephthalate, and copolymer polyesters containing these as main components. Among these, a combination of nylon-6 / polyethylene terephthalate is preferable from the viewpoints of production stability and cost.

  As the composite form of the peelable split type composite fiber, at least a part of the joint interface between the polyester polymer and the polyamide polymer has reached the circumference of the fiber cross section and can be peeled and split into each component by mechanical treatment or the like It is necessary to become. In addition, it is desirable from the viewpoint of the separation property that one component is divided into a predetermined number by the other component. Among these, a cross-sectional shape in which one component is arranged radially between other components is preferable. Such a composite form can be obtained by, for example, composite spinning a polyester polymer and a polyamide polymer using a composite spinneret described in JP-A-54-38914.

  In the present invention, the ratio of the arc length (A) of the polyamide polymer to the arc length (B) of the polyester polymer occupying the fiber cross-section circumference (hereinafter referred to as polymer component arc length ratio (A / B)). It is desirable to arrange the two components so that is in the range of 0.1 to 2.0, more preferably in the range of 0.2 to 1.5.

  When the polymer component arc length ratio (A / B) exceeds 2.0, the opening property is significantly lowered, and the nonwoven fabric weight and the strength are reduced. It is presumed that the polyamide-based polymer has a relatively low glass transition point, is slow to solidify, easily adsorbs moisture, and the fibers tend to adhere to each other, resulting in poor opening. On the other hand, when the polymer component arc length ratio (A / B) is less than 0.1, the external stress is not sufficiently applied to the two-component bonding interface during the separation process, and the separation process becomes difficult.

  The arc length of each polymer component can be arbitrarily set by changing the method of joining the polymer components in the composite spinneret, the weight ratio, or the viscosity ratio at the confluence portion in the die. In particular, by setting the melt temperature (hereinafter referred to as the conduit polymer temperature) immediately before the melt-extruded polymer flows into the spin block, the melt viscosity of each polymer is changed, and the polymer component arc length is changed. A method of setting the ratio (A / B) is simple and preferable.

  The number of divisions of the exfoliated and divided composite fibers arranged in this way can be arbitrarily set by a method in which the two components are melted and merged in the spinneret. Considering the single yarn fineness of the composite fiber that can be stably spun, it is desirable to set the number of divisions to 4 to 48, more preferably 8 to 24.

  In addition, if the composite ratio with respect to the whole of one component of the peelable split type composite fiber is in the range of 30 to 70% by weight, particularly in the range of 40 to 60% by weight, the spinning process becomes more stable and the cross section of the cross section is stabilized. Type composite fiber is suitable. When outside this range, it is difficult to adjust the viscosity balance of both polymers, section defects during spinning are likely to occur, and the separation efficiency is liable to decrease.

  The cross-sectional shape of the whole peelable conjugate fiber is arbitrary, such as a round cross-sectional shape, a multi-leaf cross-sectional shape, and a polygonal shape, and may have a hollow portion. In the case of a cross-sectional shape having a hollow part, the length of the two-component bonding interface is shortened, so that the separation of separation is further improved.

  Furthermore, in the present invention, at least one component of the two-component polymer contains 0.3 to 3.0% by weight, preferably 0.5 to 2.0% by weight of polyalkylene glycols. The organic metal salt must be contained in an amount of 0.5 to less than 3.0% by weight.

By blending polyalkylene glycols with at least one polymer, significant static electricity generated during thinning and fiber collection, especially in the spunbond long fiber process, can be greatly suppressed and evenly opened. The fibers can be collected in a web shape in a fine state. However, the addition of polyalkylene glycols is not sufficient for the effect of suppressing static electricity, and in the present invention, it has been found that static electricity is remarkably suppressed by adding together an organometallic salt represented by R-SO ₃ M. . The organometallic salt represented by R—SO ₃ M is known to have an antistatic effect, and it is within the expectation that the addition of this can prevent the non-woven fabric from being charged. It is an effect beyond expectation that the splitting property is greatly improved together with the antistatic property by coexisting the organic metal salt represented by R-SO ₃ M with the alkenyl group. By using polyalkylene glycols, the interfacial delamination between the polyamide and the polyester component is improved to some extent, but further, interfacial delamination is facilitated synergistically by coexisting an organometallic salt represented by R-SO ₃ M, The improvement of the splitting property is manifested. In particular, when a mechanical stress is applied in the presence of water, good splitting properties are exhibited. The reason for this is not clear, but not only the affinity between the fiber polymer polymer and water due to the organic metal salt represented by the highly polar R—SO ₃ M is improved, but also polyalkylene glycols in the polymer. It is believed that the dispersibility of the polyalkylene glycols that facilitate interfacial peeling at the polyester / nylon interface increases and the probability of splitting increases greatly.

  When the amount of polyalkylene glycol added is less than 0.3% by weight, the static electricity suppressing effect cannot be obtained, the component peeling effect is reduced, and the separation of the two components becomes difficult. When the addition amount of polyalkylene glycol exceeds 3.0% by weight, or when the addition amount of the organometallic salt exceeds 3.0% by weight, the viscosity of the polymer to be added decreases, and spinning becomes difficult. Problems such as deterioration of the physical properties of the non-woven fabric due to fibrillation occur.

  Examples of the polyalkylene glycols used in the present invention include polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, ethylene oxide / propylene oxide block, and random copolymer. These may be blocked with an alkyl group, an aryl group, an acyl group or the like, or may be a block polyether ester or a block polyether amide obtained by reacting various glycol components, amine components, and acid components. Among these, those whose ends are blocked with an alkyl group are more preferable because light resistance is improved.

  Polyalkylene glycols having an average molecular weight of 2000 to 600000 can be used. Those having an average molecular weight of 4,000 to 100,000, particularly 5,000 to 50,000 are easily available, and are preferable because they have good spinning stability.

As the organic metal salt, a sulfonic acid metal salt represented by R—SO ₃ M is preferably used. Here, R is an alkyl group having 8 to 15 carbon atoms, M is an alkali metal or an alkaline earth metal, and among these, Na is preferable. Examples include dodecyl benzene sulfonic acid, tridecyl benzene sulfonic acid, nonyl benzene sulfonic acid, dibutyl naphthalene sulfonic acid, hexadecyl sulfonic acid, and dodecyl sulfonic acid, and other alkali metal salts of phosphate esters such as sodium distearyl phosphate. Etc. are also preferably used. The organometallic salt may be used alone or in combination of two or more. The blending amount is preferably in the range of 0.5 to 3% by weight.

  Polyalkylene glycols and organometallic salts are added to each fiber-forming polymer by a method of adding them in the polymerization step of the component-forming polymer, and when the composite fiber is melt-spun, the fiber-forming polymer and the polyalkylene glycol are added. Any method may be employed, such as a method of melt-kneading the mixture and the organometallic salt, and a method of kneading the melted fiber-forming polymer, the polyalkylene glycol and the organometallic salt before melt spinning. be able to. Among them, from the viewpoint of heat resistance of polyalkylene glycols and organometallic salts, and easy melt spinning, etc., a method of melt spinning after mixing the component-forming polymer chip and polyalkylene glycols. Is desirable.

  Next, the peelable split type composite fiber discharged from the spinneret is indexed and refined at a speed of 1500 to 8000 m / min, more preferably 2000 to 6000 m / min, by a high-speed traction fluid such as an ejector or air soccer, and opened. The fiber is collected on the porous collecting surface while being finely wound, and wound into a web-like sheet to form a nonwoven fabric. At that time, if treatment such as corona discharge or contact charging is performed, the spreadability is further improved.

  The nonwoven fabric of the composite fiber obtained in this manner is laminated as needed, or alone, thermally bonded as necessary, once wound up, or continuously after needle punching, etc. The entanglement process is applied to the separation separation process.

  The separation method is not particularly limited as long as the separation and separation of components can be reliably performed, and a plurality of methods may be combined. For example, examples of the mechanical separation and division method include a method of applying pressure between rollers, an ultrasonic treatment method, an impact applying method, and a stagnation treatment method.

  In the present invention, prior to the split ultrafine fiber processing of the split split composite fiber, it is important to preliminarily apply water to the long fiber nonwoven fabric and perform split processing in the presence of water. Here, the water to be applied may be mixed with a chemical that swells at least one component of the separation-divided fiber, and the application method may be a conventionally known method such as immersion in water. Good. However, in the case of aiming at densification or the like, it is preferable to perform shrinkage heat treatment subsequent to the division treatment, so it is preferable to avoid a division treatment method in which heat is applied before fiber division is performed. The dividing method using a high-pressure water stream is preferably used because the dividing process can be performed simultaneously with the confounding. Moreover, when the thing with a thin weight is required, it can also produce efficiently by slicing the thing with the high weight obtained according to the use of wiping.

  The single yarn fineness after the separation treatment is suitably in the range of 0.01 to 0.30 dtex in order to impart high wiping properties as a wiping cloth. Those having a thickness of less than 0.01 dtex tend to be difficult to separate by peeling, or the fibers after the separation and separation are so thin that sticking occurs between the fibers. On the other hand, if it exceeds 0.30 dtex, the wiping property is lowered and the fiber is too thick, making it difficult to obtain a uniform and fine nonwoven fabric.

  Such fine fineness after separation by separation is determined from the single yarn fineness and the number of component divisions of the separation-division type composite fiber. The single yarn fineness before splitting of the peelable split composite fiber is preferably 1 to 10 dtex. If the single yarn fineness before splitting of the peelable split composite fiber is less than 1 dtex, yarn breakage is likely to occur during spinning. If the single yarn fineness before separation of the peelable split composite fiber is greater than 10 dtex, it becomes difficult to make the fineness after the peel splitting finer.

Hereinafter, the present invention will be described more specifically with reference to examples.
In addition, each item in an Example was measured with the following method.
(1) Detachment division ratio A cross section of the nonwoven fabric was photographed at 200 times with an electron microscope, the cross-sectional area of 50 fibers was measured, and the entire area and undivided (not completely separated by separation, for example, 2 pieces And the difference in the cross-sectional area of the fibers (including those separated and separated into about 3 pieces) was obtained by dividing by the total area.
(2) Single yarn fineness after separation after separation The composite fiber immediately after being spun from the base and pulled at high speed by the air flow is sampled, and the length is measured using a fineness measuring instrument (SERCH CO. LTD, model DC-21). The measurement was performed at 2.5 cm and a load of 0.3 g, and the composite fiber fineness was determined from the 10 average single yarn finenesses.
Single yarn fineness after separation after separation = average single yarn fineness of composite fiber / number of divisions / (exfoliation division ratio / 100)
(3) Antistatic property After the non-woven fabric was rubbed with the glass plate, the surface static electricity amount of the non-woven fabric was measured with an electrostatic potential measuring device (STATIRON DZ3, manufactured by Sisid Electric Co., Ltd.).
(4) Wiping property A colored liquid (Suminol Fast Blue 4GL: 0.2%, water: 20.0%, ethylene glycol (degree of polymerization 300): 79.8%) is placed on an acrylic plate having a size of 30 cm × 20 cm. After uniformly applying on the screen printing stage, an 8 cm × 6 cm sample having a load of 200 g was slid at 2000 mm / min on the acrylic plate, and the ratio of the colored liquid remaining on the acrylic plate was determined. Measurements were taken after taking photographs, and the results were shown as follows.
○: The residual liquid on the acrylic plate is less than 20% of the coating amount. X: The residual liquid on the acrylic plate is 20% or more of the coating amount.

[Example 1]
Polyethylene glycol having a molecular weight of 20000 (manufactured by Nippon Oil & Fats Co., Ltd.) and 2.0% by weight of sodium dodecylbenzenesulfonate with respect to nylon-6 (intrinsic viscosity 1.2 in m-cresol) dried at 120 ° C. A 1% by weight blended mixture was fed to an extruder and melted. Separately dried polyethylene terephthalate (at an intrinsic viscosity of 0.64 in o-chlorophenol) at 160 ° C. was melted with an extruder separate from the foregoing.

  Subsequently, the polyethylene glycol / organometallic salt / nylon-6 mixture melt flow was introduced into a spin block maintained at 275 ° C. at a conduit polymer temperature of 245 ° C. and a polyethylene terephthalate melt flow at 300 ° C. No. 38914 and a rectangular spinneret having 3200 round cross-section discharge holes in a grid arrangement in a range of 100 cm × 20 cm in width, the both polymer melt flows at a flow rate ratio of 50 / 50 g of air and a 120 cm wide slit with air pressure of 230 kPa (spinning speed converted from the discharge rate and composite fiber fineness, about 2700 m / min) Towed at high speed.

The pulled fineness of the composite fiber is 3.7 dtex, and the net is a web made of a split split type composite fiber having a 16-layer multi-layer laminated cross section as shown in FIG. The fiber was opened and collected with a width of 1 m on the conveyor. Subsequently, the obtained web was continuously lightly bonded with an embossing calendar at 100 ° C. up and down, and then supplied onto a mesh screen moving at a speed of 50 m / min. After applying from a nozzle provided with a water supply nozzle at intervals of 20 mm across the direction, a division treatment was performed by a high-pressure (7.5 MPa) water flow. At that time, the hole diameter of the outlet of the high-pressure water flow was 0.1 mm, the number of holes was 601, the hole pitch was 1 mm, and the injection hole group row was 6 rows, and the treatment was performed once on the front and back of the web. Then, the moisture was squeezed with a mangle roll, and it processed with the drying and heat processing apparatus maintained at 98 degreeC atmosphere, and obtained the nonwoven fabric of 80 g / m < ² > of fabric weights. The evaluation results of the obtained wiping cloth are shown in Table 1.

[Example 2]
A blend of 0.7% by weight of polytrimethylene glycol having a molecular weight of 25000 and 0.5% by weight of sodium dodecylbenzenesulfonate to nylon-6 (intrinsic viscosity 1.2 in m-cresol) dried at 120 ° C. The resulting mixture was fed to an extruder and melted. Separately dried polyethylene terephthalate (1602 intrinsic viscosity in o-chlorophenol) was melted with an extruder separate from the above.
Thereafter, discharging, high-speed traction, collection, thermal bonding, entanglement treatment, and exfoliation division treatment were performed under the same conditions and methods as in Example 1 to obtain an ultrafine fiber nonwoven fabric having a basis weight of 80 g / m ² . The evaluation results obtained in this example are shown in Table 1.

[Example 3]
The same procedure as in Example 1 was performed except that the fineness before division was 2.5 dtex and the number of divisions was 48. The obtained evaluation results are shown in Table 1. Even with a fineness of 0.05 dtex, the division ratio was good and the wiping property was also good.

[Comparative Examples 1-4]
An ultrafine fiber nonwoven fabric for wiping cloth was obtained in the same manner as in Example 1 except that the addition amounts of polyethylene glycol and organic metal salt were changed. The evaluation results obtained in this example are shown in Table 1.

  As shown in Table 1, the wiping cloths obtained in Examples 1 and 2 within the scope of the present invention showed good antistatic properties and wiping properties, whereas the addition amounts of polyethylene glycol and organometallic salt were the same. In Comparative Examples 1 to 4 that deviate from the scope of the invention, although Comparative Example 1 is excellent in antistatic and wiping properties, there are many single yarn breaks in the spinning process, and stable production is not possible. In Comparative Examples 2 to 4, The splitting property was not sufficient and the wiping property was poor. In particular, in Comparative Example 2 in which the amount of the organic metal salt added was small, the amount of static electricity generated was large and could not be sufficiently removed when wiping dust.

  The ultrafine fiber nonwoven fabric of the present invention comprises a polyamide polymer and a polyester polymer, and has good antistatic properties and wiping properties, so that it is useful for wiping cloths for household use, electricity use, and electronic use.

The schematic diagram which showed the fiber cross section of the peeling division | segmentation type | mold composite fiber of this invention.

Explanation of symbols

1: Polyamide polymer component 2: Polyester polymer component

Claims (2)

A wiping cloth that is composed of two components of a polyamide polymer and a polyester polymer, and is obtained by splitting and thinning a nonwoven fabric made of a split split composite fiber having a split single yarn fineness of 0.01 to 0.30 dtex. In the method for producing an ultrafine nonwoven fabric, 0.3 to 3.0% by weight of polyalkylene glycols and 0.5 to 3.0% of an organometallic salt represented by R—SO ₃ M are contained in at least one polymer. A method for producing an ultrafine nonwoven fabric for wiping cloth, characterized in that it is made into a split split-type composite fiber containing% by weight, and after being made into a nonwoven fabric, it is split in the presence of water.
(Here, R is an alkyl group having 8 to 15 carbon atoms, and M is an alkali metal or alkaline earth metal.) A wiping cloth that is composed of two components of a polyamide polymer and a polyester polymer, and is obtained by splitting and thinning a nonwoven fabric made of a split split composite fiber having a split single yarn fineness of 0.01 to 0.30 dtex. An ultrafine nonwoven fabric for use, wherein at least one polymer of the release-partitioned composite fiber contains 0.3 to 3.0% by weight of a polyalkylene glycol and an organometallic salt represented by R—SO ₃ M in an amount of 0. An ultrafine nonwoven fabric for wiping cloth, comprising 5 to 3.0% by weight.
(Here, R is an alkyl group having 8 to 15 carbon atoms, and M is an alkali metal or alkaline earth metal.)

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