KR101341293B1 - Flame resistant fiber blends, fire and heat barrier fabrics and related processes - Google Patents

Abstract

A flame resistant (FR) fiber blend comprises amorphous silica fibers; and at least one fiber selected from the group consisting of FR fibers, binder fibers and mixtures thereof. A barrier fabric, manufactured from a blend of fibers comprises amorphous silica fibers; and at least one fiber selected from the group consisting of flame resistant (FR) fibers, binder fibers and mixtures thereof. A flame resistant fabric, manufactured from a blend of fibers comprises amorphous silica fibers; and at least one fiber selected from the group consisting of flame resistant (FR) fibers, binder fibers and mixtures thereof. A process for protecting materials in a product from fire and heat comprises assembling a flame resistant fabric adjacent to at least one component that comprises a material susceptible to damage due to exposure to fire and heat, occasioned by exposure to open flames.

Description

Flame Retardant Fiber Blends, Fire and Heat Barrier Fabrics and Related Processes {FLAME RESISTANT FIBER BLENDS, FIRE AND HEAT BARRIER FABRICS AND RELATED PROCESSES}

Cross Reference to Related Applications

This application is a continuation-in-part of U.S. Application No. 11 / 001,539, filed Jan. 30, 2004, and the benefit of the provisional application of U.S. Application No. 60 / 660,620, filed March 11, 2005. Insist.

The present invention relates in particular to flame retardant fiber blends useful for making fabrics having flame resistance, including non-woven flame retardant materials such as barrier fabrics. The present invention also relates to single layer nonwovens useful for protecting items from fire and related heat, and to processes for protecting adjacent materials in assemblies using fire and heat barrier fabrics.

Flame retardant (FR) materials are employed in many textile applications. For example, the FR material is useful as a barrier layer between furniture, thick comforters, pillows, and the outer fabric and inner stuffing of mattresses. Such materials may be woven, non-waven, woven or laminated with other materials.

Flame resistance is defined in ASTM as "the property of a material in which burning combustion is prevented, terminated, or inhibited depending on the application of an ignition source that is burning or not burning with or without subsequent removal of the ignition source." The material that is flame resistant can be a polymer, a fiber or a fabric. Flame retadant is defined by ASTM as "chemical product giving flame resistance."

Flame-resistant, heat-resistant and flame retardant fabrics are generally employed as protective barriers for other materials in assemblies. Recent examples of increasing demand for protective barriers include mattresses, bedding sets, upholstered furniture, and bedding; All regulations were largely driven by the efforts of California, particularly California's Bureau of Home Furnishings and Thermal Insulation of the Department of Consumer Affairs. In an attempt to reduce the number of lives lost in fire by suppressing the amount of energy released when an item is exposed to open flames, it has led to a drive to regulate these materials.

In the case of mattresses and mattress sets, the proposed legislation was enacted in California on January 1, 2005, and similar national legislation is expected in 2007. Based on market history established over time, its value is limited to the end consumer. Mattress makers have demonstrated the need for low-cost, high-performance barrier fabrics because significant high prices that meet newly-imposed standards cannot be passed.

The flame resistance of these FR materials is typically California TB117 and TB 133 for the furniture industry; NEPA701 for curtains and packages; It is determined according to various standard methods such as California Test Blue Tin 129 of October 1992 for flammability testing procedures for mattresses in public buildings, and California Test Blue Tin 603 for residential mattresses. Preferably, the FR material does not melt or grind into flames, but forms a char that prevents materials surrounded by the fabric and helps control combustion.

The protection required for flame and heat barrier fabrics is related to the other components used in the final assembly of the required product. For example, a mattress usually includes layers of foam and fiber bets for cushioning and teaking of a durable cover. Most cushioning materials consist of foam and fibers that burn when exposed to an open flame. Efforts to comply with most regulations do not involve a sense of stability or aesthetics of the mattress and are directed to defending the inner cushioning layer from ignition due to open flames or heat from open flames.

Other desirable properties of FR barrier fabrics include white or other neutral colors for changing the appearance of the composite article without contaminating the manufacturing equipment; The ability to remain unaffected by UV light so that the appearance of the upholstery fabric or light colored mattress teak does not yellow or change; Soft to the touch, thus imparting the feeling required by the consumer; And cost effectiveness.

Some fibers, such as halogen-containing, phosphorus-containing, and antimony-containing materials, are known to have FR properties. These materials, however, are heavier than types similar to non-FR materials, and they reduce wear life.

In the industry of making nonwoven barrier fabrics, it is still required to be able to pass strict flammability test guidelines. In addition, there is a need in the industry to produce nonwoven products from materials that are relatively inexpensive and have a light bat weight. Additionally, other industries will benefit from the availability of flame retardant fabrics made from fibers having flame retardant properties used instead of fabrics having no flame retardant properties.

For example, baghouse filters are used to control certain pollutants in many industries, such as food processing, cement, minerals, and assembly processes, metal processing, power generation, and the production of various chemicals. This type of filter fabric is ideally suitable for (1) sufficient mechanical strength to withstand the pressures generated during use and multiple cycles of bending, (2) resistance to harsh chemicals for extended periods of time, and (3) 482 ° C (900 ° F). Ability to be unaffected by continuous process temperatures as high as: (4) resistance to hot sparks, (5) shrinkage of less than about 1% at service temperature, (6) high filtration efficiency, and (7) Has resistance to attack

There remains a need for low cost flame and heat barrier fabrics that protect other components of the assembly of products that are required for the assembly to meet all consumer and regulatory requirements.

A brief summary of the invention

In general, the present invention relates to amorphous silica fibers; And at least one fiber selected from the group consisting of FR fibers, binder fibers, and mixtures thereof.

The present invention further provides amorphous silica fibers; And a fiber blend comprising at least one fiber selected from the group consisting of FR fibers, binder fibers, and mixtures thereof.

In addition, the present invention is amorphous silica fiber; And a fiber blend comprising at least one fiber selected from the group consisting of FR fibers, binder fibers and mixtures thereof.

The process of protecting the materials in the product from fire and heat includes assembling a flame resistant fabric adjacent to at least one component comprising a material that is easily damaged due to exposure to fire and heat upon exposure to an open flame.

Advantageously, it has been found that when a fiber blend comprising amorphous silica is formed of a nonwoven, it shows an improved wet strength as compared to a nonwoven comprising no amorphous silica. The wet strength to weight ratio of nonwovens comprising amorphous silica was also improved when compared to nonwovens comprising other fibers commonly used to improve wet strength, such as para-aramid fibers and melamine fibers.

DETAILED DESCRIPTION OF THE INVENTION

The practice of the present invention includes two types of fiber blends: the first comprises amorphous silica and at least one type of FR fiber, and the second comprises amorphous silica fiber and at least one type of binder fiber. As will be described in more detail herein, fiber blends can then be used to formulate fabrics of various uses, ie both nonwovens and wovens.

In general, certain amorphous silica fibers may be used that enhance the char strength when added to the fiber blend. The term "silica" refers to silicon dioxide which occurs naturally in various crystalline and amorphous forms. Silica is considered crystalline if the basic structure of the molecule (a silicon tetrahedron with each oxygen atom arranged in common on two tetrahedrons) is repeated and symmetric. If the molecule lacks the crystal structure, the silica is considered amorphous. SiO ₂ molecules are randomly linked and do not form a repeating pattern. Crystalline silica is not required because of the associated health effect of the brittle crystal structure of crystalline silica being broken into pieces of inhalable size.

Amorphous silica fibers are high-content silica fibers having a silica (SiO ₂ ) content of at least about 90 weight percent based on the total weight of the high silica fibers. In one or more embodiments, the high silica fibers have a silica content of at least 95 weight percent, and in other embodiments the high silica fibers have a silica content of at least 98 weight percent. For example, the high silica fiber may comprise about 98 weight percent silica with a balance comprising primarily alumina. In certain embodiments, the amount of halogen in the high silica fiber is below the minimum acceptable level, i.e., at least 120 parts per million by weight.

As mentioned above, the silica fibers are substantially amorphous. Although the fiber contains some crystalline material, no substantial amount of crystal is required. Suitable silica fibers are readily available commercially, for example Belarus from Polotsk-steklovokno.

In one embodiment, the starting material composition for high silica fibers comprises: based on the total weight of the composition, all percentages are by weight, from about 72 to about 77% SiO ₂ , from about 2.5 to about 3.5% Al ₂ O ₃ , From about 20 to about 25% Na ₂ O, from about 0.01 to about 1.0% CoO and from about 0.01 to about 0.5% SO ₃ . The composition may melt at about 1480 ± 10 ° C. to form continuous fibers. These fibers can then be leached with hot sulfuric acid at a concentration of 2N at a temperature of about 98 ± 2 ° C. with a downtime of about 60 minutes. The fiber can then be rinsed with tap water until the pH is about 3-5. In this embodiment, the resulting fiber has a SiO ₂ content of about 95 to about 99 ± 1 weight percent, with the remainder mainly Al ₂ O ₃ .

Processes for making high silica glass compositions and high silica fibers are described in Russian Patent 2,165,393 (the '393 patent), which is a reference of the present invention. In the '393 patent, high silica fibers are described as having a low coefficient of change in strength of the base filament, which gives the possibility of stabilizing the resulting fiber's strength properties, especially at high temperatures. The following description of high silica fibers is taken from the '393 patent for illustrative purposes and should not be construed as limiting the invention.

In one or more embodiments, the precursor organic composition may comprise SiO ₂ , Al ₂ O ₃ , and Na ₂ O as well as CoO and SO ₃ in the following proportions (mass percent).

Al ₂ O ₃ : 2.5-3.5

Na ₂ O: 20-25

CoO: 0.01-1.0

SO ₃ : 0.01-1.0

SiO ₂ : rest

The glass may further comprise at least one oxide from the following amounts of CaO, MgO, ZrO ₂ , TiO ₂ , Fe ₂ O ₃ , group.

CaO: 0.01-0.5

MgO: 0.01-0.5

TiO ₂ : 0.01-0.1

Fe ₂ O ₃ : 0.01-0.5

ZrO ₂ : 0.01-0.5

The resulting, high temperature silica fiber from the glass composition comprises SiO ₂ and Al ₂ O ₃ in the following proportions (mass percent) and may also include Na ₂ O, CoO and SO ₃ .

SiO ₂ : 94-96

Al ₂ O ₃ : 3-4

Na ₂ O: 0.01-1.0

CoO: 0.01-1.0

SO ₃ : 0.01-1.0

The silica fibers may also comprise at least one oxide from the CaO, MgO, TiO ₂ , Fe ₂ O ₃ , ZrO ₂ groups in the following amounts (mass percent).

CaO: 0.01-0.5

MgO: 0.01-0.5

TiO ₂ : 0.01-0.1

Fe ₂ O ₃ : 0.01-0.5

ZrO ₂ : 0.01-0.5

In one embodiment, the silica fibers have substantially no metal oxide coating.

The diameter of the silica fibers may range from about 5.6 microns to about 12.6 micros, and in one embodiment, the diameter is about 8 microns. The length of the silica fibers may range from about 50 millimeters to about 125 millimeters, in one embodiment the length is about 75 millimeters. (Shorter or longer fibers are available by adjusting the length cut of the fiber, but cannot be used for needlepunch applications.)

One method of the preparation of silica fibers according to the aforementioned Russian patent 2,165,393, according to Example 1, can be carried out as follows: In order to produce continuous filament glass fibers of the proposed composition, SiO ₂ : 72.39, A container containing A1 ₂ O ₃ : 2.5, Na ₂ O: 25, CoO: 0.01, SO ₃ : 0.1 may be prepared. The vessel is loaded into a furnace and the composition is dissolved at a temperature of about 1480 ± 10 ° C. From the molten glass mass, continuous glass fibers can be formed with a diameter of 6-9 microns at a temperature of about 1260 ± 50 ° C. using a 400-hole glass-forming aggregate. The resulting fiber was found to have a strength of about 1030 Mpa and a surface tension of about 0.318 H / m.

Subsequent leaching of the glass fibers can be performed using a hot sulfuric acid solution at a concentration of about 2N (about 10%) at a temperature of about 98 ± 2 ° C. The contact time of the fibers in the solution is 60 minutes. The leaching solution, the reaction product, and the residue sorted by size are then washed from the leached fibers with tap water until the pH is about 3-5. Final washing of the fibers is carried out simultaneously with dehydrogenation with deionized water.

Preparation of the glass compositions of Examples 2 and 3 below, their processes and ching are similar to those of Example 1 above, but only in the amount of starting material. Table 1 shows the amount of material of the resulting silica composition as well as the starting amount of the glass. Table 2 shows the properties of the molten product, the properties of the process, and the properties of the glass and silica fibers. Table 3 provides the strength properties of silica materials after exposure to 1000 ° C.

Table 1-3 also shows that the introduction of cobalt and SO ₃ into the glass composition increases the heterogeneity of the glass mass, lowers its surface tension, reduces the brittleness of the fiber during the process, and based on this fiber Data are provided to confirm that it also increases the stability of the technical properties of the fibers and the resulting materials.

Tables 4 and 5 show various glass fiber compositions showing that the silica fibers according to Russian Patent 2,165,393 differ from all other glass fiber types in which trace amounts of CoO and SO ₃ are present.

So far, the amorphous silica component of the present invention has been discussed, and additional fibers will now be discussed. As mentioned above, the present invention encompasses two embodiments, one employing flame retardant (FR) fibers and the other employing binder fibers. As discussed below, the use of the term “silica fiber” should be understood to mean fibers comprising amorphous silica (as opposed to crystals).

In the first type of additional fibers, i.e., FR fibers, the amount of silica fibers in the fiber blend varies depending on the other fibers used. In one embodiment, the amount of silica fibers in the blend is about 5 to about 65 weight percent based on the total weight of the blend. In another embodiment, the amount of silica fiber in the blend is from 15 to about 50 weight percent. In another embodiment, the amount of silica fiber in the blend is 20 to about 30 weight percent. The remaining fibers in the blend include non-amorphous fibers, ie FR fibers in the amount necessary to fill 100 weight percent.

Various FR fibers are known in the art. FR fibers employed in the fabrics of the present invention may be native flame retardant fibers or (natural or synthetic) fibers coated with FR resin. Intrinsic flame retardant fibers are not coated, but have FR components incorporated within the structural chemistry of the fiber. The term FR fiber as used herein includes not only inherent flame retardant fibers but also fibers coated with FR resin, although not inherently flame resistant. Thus, for example, polypropylene fibers coated with FR resin are FR propylene fibers.

Suitable inherent flame retardant fibers include polymeric fibers having phosphorus-containing groups, amines, modified aluminosilicates, or halogen containing groups. Examples of inherent flame retardant fibers include melamine, meta-aramid, para-aramid, polybenzimidazole, polyimide, polyamideimide, partially oxidized polyacrylonitrile, novoloids, poly (p-phenylene Benzobisoxazole), poly (p-phenylenebenzothiazole), polyphenylene sulfide, flame retardant viscose rayon; (Eg, viscose rayon based on fiber comprising 30% aluminosilicate modified with silica, SiO ₂ + Al ₂ O ₃ ), polyetheretherketone, polyketone, polyetherimide, and combinations thereof.

Melamines include those sold under the trade name Basofil by McKinnon-Land_Moran LLC. Meta-aramids include poly (m-phenylene isophthalamide) sold under the trade names NOMEX ^® at EI Du Pont de Nemours and Co., TEIJINCONEX ^® and CONEX ^® at Teijin Limited, and FENYLENE ^® at Russian State Complex. . Para-aramids are, for example, poly (p-phenylene terephthalamide) sold under the name KEVLAR ^{® by} EI Du Pont de Nemours and Co., and TECHNORA ^{® by} Teijin Limited, and TWARON ^® and FENYLENE ST ^® (Acordis). Poly (diphenylether para-aramid) sold under the trade name of Russian State Complex).

Polybenzimidazole is sold under the trade name of PBI by Hoechst Celanese Acetate LLC. Include those from poly-imide Inspec Fibers P-84 ^®, and Du Pont de Nemours and Co. sold EI in the trade name of KAPTON ^®. It includes polyamide Rhone-Poulenc. Polyimide sold under the trade name KERMEL ^®. For example, in part by the polyacrylic nitrile oxide by example, FORTAFIL OPF ^®, AVOX of Textron Inc. ^® from Fortafil Fibers Inc., PYRON ^® from Zoltek Corp., PANOX ^® from SGL Technik, THORNEL ^® from American Fibers and Fabrics, and Toho Rayon Corp. include those sold under the trade names in the PYROMEX ^®.

Novoloids include, for example, phenol-formaldehyde novolac sold under the trade name KYNOL ^® in Gun Ei Chemical Industry Go. Poly (p- phenylene-benzo-bis-oxazol) (PBO) are sold under the trade name of ZYLON ^® from Toyobo Co.. Poly (p-phenylene benzothiazole) is also known as PBT. Poly phenylene sulfide (PPS) include those sold under the trade name of PROCON ^® from RYTON ^®, FORTRON ^®, and from Toyobo Co. ^® TORAY PPS, Kureha Chemical Industry Co. from Toray Industries Inc. in the American Fibers and Fabrics.

Flame-resistant viscose rayon, for example, include those in LENZING FR ^®, and Sateri Oy Finland from Lenzing AG sold under the trade name of VISIL ^®. Polyether ether ketone (PEEK) is, for example, Zyex Ltd. Included are sold under the trade name ZYEX ^{® in} the The polyketones (PEK), for example, include those under the trade name of the selling ULTRAPEK ^® from BASF. Polyetherimides (PEI) include those sold under the trade name ULTEM ^® by General Electric Co.

Modacrylic fibers are made from copolymers of acrylonitrile and other materials such as vinyl chloride, vinylidene chloride or vinyl bromide. Flame retardants such as antimony oxide may be added to further enhance the flame retardant properties. The modacrylic fibers used in the present invention are manufactured by Kaneka under the trade names KANECARON PBX, and PROTEX-M, PROTEX-G, PROTEX-S and PROTEX-PBX. The latter products comprise at least 75% acrylonitrile-vinylidene chloride copolymer. Solutia's SEF PLUS is not only a modacrylic fiber but also a flame retardant.

Additional examples of inherent FR fibers suitable for use in the blends of the present invention include polyesters with phosphalane, such as sold under the trade name TREVIRA CS ^® fiber, or AVORA ^® PLUS FIBER, in KoSa.

Also in ^{Rhovyl SA THERMOVYL ® L9S & ZCS,} FIRBRAVYL ® L9F, RETRACTYL ® L9R, ISOVYL ® MPS, in Thueringische PIVIACID ^®, Kureha Chemical Industry Co. in VICLON ^®, TEVIRON ^® from Teijin Ltd., ENVILON from Toyo Chemical Co. ^® , in ^{Pittsfield Weaving VICRON ®, SARAN ®,} Kureha Chemical Industry Co. those sold under the trade name of OMNI-SARAN ^® in KREHALON ^®, Fibrasomni, SA de CV in, and are useful, those of the chloro-polymeric fibers, such as the combination . Polytetrafluoroethylene (PTFE), poly (ethylene-chlorotrifluoroethylene) (E-CTFE), polyvinylidene fluoride (PVDF), polyperfluoroalkoxy (PFA), and polyfluorinated ethylene- Fluoropolymer fibers such as propylene (FEP) and combinations thereof are also useful.

Natural or synthetic fibers coated with FR resins are also useful for the fiber blends of the present invention. Suitable fibers coated with FR resins include one or more phosphorus, phosphorus compounds, red phosphorus, esters of phosphorus, and phosphorus complexes; Resins comprising an amine compound, boric acid, bromide, urea-formaldehyde compound, phosphate-urea compound, ammonium sulfate, or halogen-based compound. Non-resin coatings such as metal coatings are not generally employed in the present invention because they tend to fall off after successive use of the product. Suitable FR resins which are readily available commercially are sold under the trade names GUARDEX FR ^® , and FER ^® by Glotex Chemical in Spartangburg, SC.

The method in which the resin is coated on the fiber is not particularly limited. In one embodiment, the FR resin is a liquid product that can be applied by spraying. In another embodiment, the FR resin is a solid that can be applied to the fiber as a hot melt product or can be applied as a solid powder to melt into the fiber. In one embodiment, the FR resin is applied in an amount of about 6 to about 25 weight percent based on the total weight of the coated fiber.

The amount of FR fibers coated in the blend can vary, but is about 35 to about 95 weight percent based on the total weight of the blend. In one embodiment the amount of coated FR fibers in the blend is about 40 to about 90 weight percent. In another embodiment the amount of FR fibers coated in the blend is about 45 to about 85 weight percent.

The denier of the FR fibers is about 1.5 to about 15 dpf (denier per filament). The FR fibers listed above should not be construed as limiting the invention, but are intended to illustrate the fact that any known FR fiber can be employed with amorphous silica fibers and can be used in the practice of the present invention. Therefore, the types of fibers typically include fibrillated yarns made from slit films or tapes, as well as multiple filaments and single filament yarns with various cross-sectional areas and shapes.

The fiber blends of the present invention may further comprise one or more non-FR fibers. Non-FR fibers may be synthetic or natural fibers. Suitable non-FR synthetic fibers include polyesters such as polyethylene terephthalate (PET); Celluloses such as rayon and / or lyocells; nylon; Polyolefins such as polypropylene fibers; Acrylic fibers; Melamine and combinations thereof. Lyocell fibers are a comprehensive class of solvent-spun cellulose fibers. These fibers are commercially available under the name TENCEL ^® . Natural fibers include flax, kenaf, hemp, cotton, and wool. In one embodiment, non-FR fibers may be employed to enhance properties such as loft, resilience or springiness, tensile strength and thermal retention.

Fiber blends include amorphous silica fibers and at least one kind of FR fibers. Therefore, the present invention is employed in fiber blends comprising amorphous silica fibers, FR fibers, optionally additional FR fibers, and optionally one or more non-FR fibers. In one embodiment, the fiber blend comprises modacrylic fibers; Cellulose fibers, lyocells, and amorphous silica fibers.

In another embodiment, the fiber blend further comprises one or more types of FR fibers. In another embodiment, the fiber blends include amorphous silica fibers, modacrylic fibers, and VISIL. In another embodiment the fiber blend includes modacrylic fibers, FR rayon fibers, and amorphous silica fibers.

In another embodiment the fiber blend includes modacrylic fibers, VISIL (FR viscose rayon) fibers, amorphous silica fibers, and FR polypropylene fibers. The amount of each component can vary, but the advantageous char strength is about 40 weight percent modacrylic, about 40 weight percent VISIL, about 15 weight percent amorphous silica, and about 5 weight percent of the needle punched fabric. When produced from a blend comprising FR polypropylene fibers.

The fibers of the present invention can be used to make fabrics where FR properties are desired or useful. Essentially non-woven; Woven, open weave, and closed weave; All kinds of fabrics made from fibers such as knitted fabrics and various laminates can be made using the fibers of the present invention. The manufacture of such fabrics is not limited to any particular method or device. In woven fabrics, it is possible to replace amorphous silica fibers with one or more FR fibers and employ them in the machine direction or in the cross machine direction. Optionally, the fibers can be replaced in the machine direction, interwoven with amorphous or FR fibers in the cross machine direction. As a percentage, the woven fabric according to the present invention comprises the aforementioned composition for blending amorphous and FR fibers.

Nonwoven fabrics according to the present invention can be produced by mechanically interlocking a web of fibers. Mechanical engagement can be achieved through a needle punch process. Needle punch methods for making nonwovens are known in the art. In one embodiment, a nonwoven fabric, sometimes called a batt, may be constructed as follows: Weigh the fiber blend, dry lay / air laid on a moving conveyor belt. The speed of the conveyor belt can be adjusted to provide the required bat weight. Multiple layers of batt are provided past the needle room where barbed needles are driven through the layer to provide entanglement.

Various other methods are known for producing nonwoven fabrics including hydroentanglement (spunlace), thermal bonding (through calendaring and / or air), latex bonding or adhesive bonding processes. The spunlace method is similar to a needlepunch except that a waterjet is used instead of the needle to entangle the fibers. Thermal bonding requires a powder that acts as a type or binder if it is a thermoplastic fiber. All types of nonwovens can be made with the FR fiber blends of the present invention to make barrier fibers with FR properties. Thus, all forms of manufacture are a reference to the nonwovens herein.

Suitable nonwovens of the present invention may comprise about 2.25 oz./sq.yd. has a bat weight greater than (osy). In one embodiment, the bat weight is in the range of about 2.25 osy to about 20 osy. In another embodiment, the bat weight is about 3.5 osy. In one embodiment, the fibers are carded. The conveyor belt then moves to an area where spray-on material can optionally be applied to the nonwoven bat. For example, the FR resin can be sprayed onto the nonwoven bat as a latex. In one embodiment, the conveyor belt is foraminous, and excess latex spray material may fall through the belt and be collected for later reuse. After any spray, the fiber blend is shipped to a dryer or oven. The fibers can be transported by the conveyor belt to a needlepunch room where the fibers of the bat are mechanically arranged and interlocked to form a nonwoven.

Non-woven FR fabrics are useful as barrier fabrics for bedding materials and bedding. Fabrics are also useful for applications in upholstery and wrapping that require flame resistance. In addition, other fabrics besides nonwovens, where FR fabrics are required, may also be made from the fibers of the present invention.

The figure in the figure is an exploded perspective view showing the assembly of a tuft button test apparatus.

General experiment

In order to demonstrate the effect of various fiber blends as FR materials, many samples were prepared and tested as follows. The examples demonstrate the practice of the invention, but should not be construed as limiting the invention or its application.

Examples 4-15

Samples were prepared on miniature carding machines and needle rooms. The fibers were first hand-opened and laminated onto carding machine infusion aprons. The carded samples were reversed twice through a carding machine to ensure initial blending of the fibers. The carded web stacked near the wind-up roll was cut horizontally and removed from the carding machine. It was then injected into a needle punch line for needling. A second pass was performed to achieve the needling of the opposite side.

The standard tensile strength tester was modified to measure the wet strength of the barrier fabric of the present invention. More specifically, the stiffness test of fabrics in which pocket coil materials are typically used was modified to measure the amount of force required to push the fabric sample through the hole into the plunger, measured and reported in pounds. . In order to force the material to break, the template was fabricated so that the fabric could be sandwiched between the template and the existing test plate.

Specimens of barrier fabrics were cut and weighed into 4 "x 8" (10 x 16 cm) samples. Samples were placed in charring frames and burned using Bunsen burners. The frame was then installed on a modified stiffness tester and the shock strength of the sample was measured. Table 6 summarizes the results of Examples 4-15. As a reference, modacrylic selected the 40% blend and comprising a sweeping of 60% (Example 4) was used for the following types of fibers: Basofil ^® (an abbreviation Bas); Modacrylic fiber KANECARON PBX; VISIL ^® (abbreviated Vis); Polyethylene terephthalate (abbreviated PET); And amorphous silica (abbreviated Sil). Examples 5-11 and 13-14 are comparative fibers made from various fiber blends as pointed out. Examples 5 and 6 included 10% Basofil fibers as equivalent replacements for modacrylic or non-silicone fibers; Examples 7 and 8 comprise 10% and 20% of PET fibers as equivalent replacements of the non-ferrous fibers; Example 9 comprises 10% Basofil fibers together with PET fibers, modacrylic fibers and amorphous fibers; Examples 10 and 11 include 10% and 15% of PET fibers as substitutes for various amounts of modacrylic and amorphous fibers; Examples 13 and 14 include 10% Basofil fibers as substitutes for various amounts of modacrylic and amorphous fibers; Examples 12 and 15 were prepared from fiber blends comprising amorphous silica fibers, according to the present invention.

When the wet strength of the fabric is related to the weight of the sample, it can be seen that the fabrics formed from the fiber blend comprising amorphous silica (Examples 12 and 15) show an strength to weight ratio of 0.08 to about 0.10.

Example  16-45

As summarized in Table 7, Examples 16-45 were prepared and tested as in Examples 4-15, except that different fiber blends were used. The strength of each fabric is expressed in pounds as discussed above. Fabrics were reported in six groups of four blends and two groups of three blends. Examples 19, 23, 27, 31, 34, 38, 41, and 45 report base fabrics and report the addition of various types of FR fibers. Shock strength was measured in pounds and the results were reported as reduced values for each group.

For example, FR rayon and modacrylic fibers were used to prepare Example 19, indicated as FR rayon / modacrylic base fabric. Examples 16-18 are variations of this base fabric, in each case adding different types of FR fibers: According to the invention, para-aramid fibers were added to Example 16, and melamine fibers were added to Example 17. Was added and amorphous silica fiber was added to Example 18.

Similarly, Example 23 was made from rayon fibers and represented as FR rayon base fabrics, and Examples 20-22 are variations of this base fabric: Para-aramid fibers were added to Example 20 according to the present invention, Melamine fibers were added to Example 21 and amorphous silica fibers were added to Example 22.

In addition, in the present invention, Example 27 is a rayon / modacrylic base fabric and Examples 24-26 are variations of this base fabric: melamine fibers were added to Example 24 and para-aramid fibers were added to Example 25 Was added and amorphous silica fiber was added to Example 26.

Example 31 is a lyocell / modacrylic base fiber and Examples 28-30 are variations of this base fabric: para-aramid fiber was added to Example 28, melamine fiber was added to Example 29, amorphous silica Fiber was added to Example 30.

In the next series, Example 34 is a non-silicone / modacrylic base fabric and Examples 32, 33 and 35 are variations of this base fabric: In accordance with the present invention, para-aramid fibers were added to Example 32, amorphous silica Fiber was added to Example 33; Melamine fibers were added to Example 35.

Example 38 is an amorphous base fabric and Examples 36-37 are variations of this base fabric: In accordance with the present invention, melamine fibers were added to Example 36 and amorphous silica was added to Example 37.

In the present invention, Example 41 is a rayon base fabric, Example 39 comprises rayon and melamine, and Example 40 comprises rayon and amorphous silica.

In the present invention, Example 45 is a lyocell base fabric, Example 42 comprises paraaramid, Example 43 comprises lyocell and melamine, and Example 44 comprises lyocell and amorphous silica.

 It can be seen from the data in Table 7 that a fabric comprising 10% by weight amorphous silica shows improved shear strength as compared to the same base fabric without amorphous silica, ie Example 18 compared to Example 19. It is generally noted that the use of other FR materials, namely para-aramid and melamine with base fabrics, provides stronger strength than blends comprising amorphous silica, but these two materials are much more expensive than silica. In addition, aramids have a golden yellow color on the fabric and melamines have an off-white color. Amorphous silica is not so that the resulting fabric is white without the addition of dyes. Finally, the wet strength of fabrics comprising amorphous silica is more than necessary for utility in bedding, apparel, upholstery, packaging, and related purposes.

Example  46-53

Examples 46-53 were made using a needle punch line comprising a 12 inch carding machine, a cross wrapper, and a 24 inch dilo OD-1 needle room. Example 46 is a base blend (8osy) comprising 40% modacrylic and 60% amorphous, and in the following examples various materials or FR fibers were employed. Example 47 includes a blend of base blend (79%) and Leno woven carpet backing, 2.1 osy, (21%). Example 48 includes a blend of base blend (89%) and coned scrim 1 osy (11%). Coned is a very lightweight polypropylene material of "welded" "warp" and "fill" monofilaments that are "welded" together at the apex to provide a "leno type" appearance. Example 49 includes a blend of base blend (85%) and Basofil (melamine, 15%). Example 50 includes a blend of base blend (85%) and Conex (Conex 15%). Conex is meta-aramid. Example 51 includes a blend of base blend (85%) and amorphous silica (15%). Example 52 includes a blend of base blend (85%) and Kynol (phenol-formaldehyde novolac, 15%). Example 53 includes a blend of amorphous silica (15%), modacrylic fiber (40%), and amorphous fiber (45%). Example 53 shows a fabric of the present invention.

The tuft button simulation is designed to expose the burned fiber to the stresses found in the actual mattress seats and to guide the pass / fail for fabric strength. Small test rigs were dried on wood. The components were assembled as shown in the figure to form a tuft button test device 10. 4 inch foam (12), two 1 inch super-soft foams (14), (16), barrier fabric (18), 0.5 ounce per square foot (osf), PET fiber filler (20), and PET teaking fabric ( Mattress components comprising 22) were combined as described below and then burned under tension.

The components were assembled at the top of the upper plate 24. The foam components 12, 14, and 16 were compressed to pack the barrier fabric 18, the fiber peel 20, and the ticking 22 around all sides of the top plate 24. The lower plate 26 was positioned to sandwich the fabrics 18, 20, 22 between the upper plate 24 and the lower plate 26. The tuft button simulator 28 is coupled to the threaded rod 30, the rods 30 passing through all the mattress components, and the holes 32 arranged in the upper and lower plates 24, 26, Pushed through 34. The wing nut 36 applied tension to the assembly and fixed the rod 30 by pulling the tuft button simulator 28 towards the foam.

The TB 603 upper burner 28 was placed in the center of the tuft button simulator 10, ignited and burned for 70 seconds. The results are summarized in Table 8.

In some advanced full-mattress burns of various structures, an 8 osy needlepunch fabric of 60% amorphous / 40% modacrylic successfully passed the criteria of California Test Bulletin 603. The fabric was only unsuccessful when this barrier was in a tensioned structure after charring. As adjusted, 8 osy fabrics were used (Ex No. 46) to show that these full scale tests performed in accordance with the known fabric performance dl bench test. The sample cracked the area around the tuft button within 30 seconds and the entire assembly burned out completely within 40 seconds. This was the required performance because it accurately describes the performance at full-scaling burns. Example 47 used an 8 osy fabric in composite with a 2.1 osy lenosecondary carpet backing fabric. As before, it cracked within 20 seconds and was recovered as a possible solution. Similarly Example 48 used a polypropylene scrim, which is a very light weight (about 1 osy) giving it a "lenostatic appearance". Although it is not a woven fabric, the tops of the best "wrap" and "fill" monofilaments have been fused together. This sample also cracked within 1 minute.

The remaining samples prepared were not composites, but the needled fiber blend was performed on a pilot line carding machine / cross wrapper / needle room assembly. These samples can also be produced at low weight, providing an economic advantage. Example 49, the first fabric evaluated, was a 6 osy fabric consisting of 15% melamine, and a "base blend" of 85% 60/40 bead / modacrylic. These fabrics cracked within 30 seconds and burned out of control. It was removed from candidates of this application. The 6 osy fabric, consisting of 15% meta aramid of Example 50 and 85% of “base blend” of 60/40 bead / modacry, also cracked and uncontrolled burned within 25 seconds. The 6osy fabric of Example 51, 15% amorphous silica, and 85% "base blend" of 60/40 amorphous / modacrylic was not cracked and the complete assembly was fully self-extinguishing within 8 minutes of ignition. Similarly, the 6 osy fabric, consisting of Example 52, 15% of novoroids, and 85% of "base blend" of 60/40 non-silicone / modacrylic, was not cracked and self-digested within 11.5 minutes. Many other fibers were considered for this demonstration, but some expensive fibers were excluded for economic reasons. In accordance with this attempt, a 5 osy fabric consisting of the fabric according to the invention, 15% of the amorphous silica of Example 53, and 40% of modacrylic, 45% of the material, was assembled in the tuft button simulator rig, which also did not crack. In fact, it self-digested in about 13 minutes.

The use of amorphous silica fibers with FR fibers proved to be very effective in providing FR fabrics, a second embodiment will be discussed next.

As mentioned above, the present invention is directed to a single layer nonwoven fabric useful for protecting items from fire and associated heat; And a process for protecting adjacent materials in the assembly using fire and heat barrier fabrics. The nonwoven barrier is at least about 0.45 ounces of amorphous silica fiber per square yard and at least about 0.45 ounces of binder fiber per square yard: single layer nonwoven having a basis weight of at least about 3.0 per square yard. By weight of the nonwoven fabric, the fiber blend comprises from about 15 to about 80 weight percent of amorphous silica fibers, from about 15 to about 85 weight percent of binder fibers, with a total of 100 reductions with the other two fibers without dropping below the minimum amount. It may include up to about 70 weight percent of complementary fibers to be in weight percent, which is not necessary.

As discussed above, amorphous silica fibers are always present in the nonwoven composition and comprise at least about 15 weight percent and less than about 80 percent of the fiber blend. In one embodiment, the amorphous silica fiber comprises the fiber blend in about 35 to about 50 weight percent. As the weight blend percentage of silica fibers decreases, the effect of single layer nonwovens blocking open flames and heat is reduced. Although individual amorphous silica fibers are resistant to burning and melting at levels of less than about 15 weight percent of the nonwoven, at least this level is maintained to provide proper structure and integrity in the nonwoven structure during and after exposure to open flames. Should be. At least about 15 percent by weight of amorphous fibers are required in the nonwoven to maintain some acceptable level of warp strength.

The blend weight percentage of amorphous silica is limited to no more than about 80 weight percent of the weight of the described nonwovens to maintain the functional properties required for fire and thermal barrier fabrics. The fiber-to-fiber adhesion of amorphous silica requires at least about 20 weight percent more cohesive fibers for sufficient fiber web strength and fiber entanglement in the nonwoven. What makes this single layer nonwoven unique is this entanglement combined with thermal bonding. The combination of mechanical and thermal bonds results in a nonwoven structure that enables at least one of the following without limiting the function of preventing flame and heat in at least one embodiment, and in other embodiments, defining a function of preventing flame and heat. Without the majority of the following are possible nonwoven structures, and in another embodiment, the following are all possible nonwoven structures without limiting the ability to prevent flames and heat.

i) capable of retaining the stitches stitched in the sewn assembly without the support of an additional layer of fabric, as is required for the support and the thermally bonded nonwovens conventional for reinforcement

ii) It is possible to maintain thermal stitches in the ultrasonically bonded assembly without the support of additional fabric layers, as required by the support and conventional thermally bonded nonwovens for reinforcement.

iii) It is possible to maintain thermal stitches in thermally bonded assemblies without the support of additional fabric layers, as required by the support and conventional thermally bonded nonwovens for reinforcement.

iv) maintains the integrity of the nonwoven structure as the surface layer of the assembly, especially without excessive polishing between exposed surfaces, compared to materials with FR surface coatings.

v) Colors can be blended to avoid aesthetically unpleasant contrasts in different material and aggregates of colors, as in many conventional flame retardant materials. (Natural color is white and blending hue is the color of binder fibers or other additional fibers. Can be achieved by heating

vi) the use of a moving and / or contacted assembly is possible without excessive noise associated with its nonwoven structure.

vii) In order to provide a satisfactory quilted seam depth for aesthetic enjoyment in the sewing-sewn assembly, it is possible to loft sufficiently, lower density and larger thickness. (Not the usual needle punch structure)

viii) sufficiently lofted, lower density and larger thickness are possible to provide a satisfactory quilted seam depth for aesthetic enjoyment in an ultrasonically bonded assembly. (Not the usual needle punch structure)

ix) sufficiently lofted, lower density and larger thickness are possible to provide a satisfactory quilted seam depth for aesthetic enjoyment in heat bonded assemblies. (Not a normal needle punch structure)

x) It is possible to maintain flame and heat protection efficiency even after exposure to moisture (no performance system aqueous solution that can be washed).

xi) Provides sufficient stiffness of the hand to prevent wrinkles, gathering and / or gathering around the cross section, which is generally an issue with softer structures.

In addition to amorphous silica fibers, binder fibers are always present in the nonwoven composition and are included at least 15 weight percent in the fiber blend. In one embodiment, the amorphous silica fibers comprise 50 to 65 percent by weight fiber blend. While binder fibers are essential for the thermal bonds required for nonwoven barrier fabrics, multi-component binder fibers also provide a mechanical and thermal role in the nonwoven structure. Mechanically, at least one fiber must provide sufficient fiber-fiber adhesion to maintain entanglement of the fibers between the amorphous silica fibers to maintain sufficient structure and integrity of the fibrous web after thermal bonding. Such sticky fibers may be components of binder fibers (in the case of multi-component binder fibers) that remain intact after thermal bonding, or may be fibers or fibers added to the amorphous silica and binder fibers in the blend.

The binder fiber may be a single component, low melting point fiber that acts strictly as a binder for the thermal bonding necessary in nonwovens. Representative single component fibers include low melting polyethylene terephthalate, polypropylene, polyethylene, low density polyethylene, linear low density polyethylene, polylactic acid, polytrimethylene terephthalate, polycyclohexanediol terephthalate, polyethylene terephthalate glycol, nylon 6 , Nylon 6,6, nylon 11, nylon 12, polymethyl pentene and other thermoplastic polymers having sufficiently low melting points, inherent or modified. "Low enough" means that the thermoplastic fiber has the lowest melting point of all the component fibers present. Some polymers inherently have the lowest melting point, while others, such as polyester, may need to be modified with suitable additives to have a lower melting point than inherently processed by an unmodified polymer.

Single-component binder fibers comprise at least 15 weight percent of the fiber blend of the nonwoven. In connection with this invention, when single-component binder fibers are used, it is required to add at least 15 weight percent of the highly tacky fibers for mechanical fiber engagement after thermal bonding. Single-component binder fibers should have a melting point of less than 107 ° C., but the melting point should not exceed 10 ° C. above the lowest melting point of any other structure of fibers in the nonwoven fiber blend.

The maximum melting point of the single-component binder fibers allows the binder fibers to melt or flow so that these fibers remain at a temperature below their melting point, thereby forming a binding matrix along and between the structural fibers. The minimum temperature is varied by the end-use application of the nonwoven fire / heat barrier and is based on temperatures higher than the maximum temperature of the nonwoven barrier exposure to subsequent assembly processes and routine process usage and environments. The optimum melting point of single-component binder fibers is minimized within the range of reducing energy and time for thermally bonding the nonwoven barrier fabric.

The diameter of the single-component binder fibers ranges from about 20 microns to about 60 microns, and in one embodiment it is about 31 microns. In needle punch applications the length of single-component fibers ranges from about 50 millimeters to about 125 millimeters, and in one embodiment is about 75 millimeters. Single-component binder fibers should not serve as an auxiliary fuel source for open flames.

The binder fiber may be a multicomponent, low melting point fiber that acts strictly as a binder for thermal bonding, which is essential in nonwovens. Representative multicomponent fibers include fibers of a coextruded polymer of a combination comprising at least two of the following polymers: polyethylene terephthalate, polypropylene, polyethylene, low-density polyethylene, linear low-density polyethylene, polylactic acid, polytrimethylene Terephthalate, polycyclohexanediol terephthalate, polyethylene terephthalate glycol, nylon 6, nylon 6,6, nylon 11, nylon 12, polymethyl pentene, and other thermoplastic polymers having sufficiently low melting points, inherent or modified. The term "sufficiently low" has the same meaning as in the above mono-component fibers. Similar to single-component fibers, multi-component fibers provide two polymers that melt to provide thermal bonding.

Such multi-component thermally bonded fibers comprise at least about 15 weight percent of the nonwoven fiber blend. In the present invention, when only the multi-component binder fiber acts as a thermal binder, it requires the addition of at least about 15% by weight of highly tacky fibers for mechanical fiber engagement after thermal bonding, but not more than 70% by weight. Such multi-component thermally bonded fibers should have a melting point lower than 107 ° C., but the melting point should not exceed 10 ° C. above the lowest melting point of other structural fibers in the nonwoven fiber blend.

The maximum melting point of the multi-component thermally bonded fibers causes the binder fibers to melt and flow, making it possible for these fibers to remain at temperatures below their melting point, thereby forming a binding matrix along or between the structural fibers. The minimum temperature is varied by the end-use application of the nonwoven fire / heat barrier, which is based on temperatures higher than the maximum temperature exposure of the nonwoven barrier in subsequent assembly processes and routine process use and environments. The optimum melting point of the multi-component bonding fibers is minimized within the range of reducing the time and energy required to thermally bond the nonwoven barrier fabric.

The diameter of the multi-fiber binder fibers ranges from about 20 microns to about 60 microns, and in one embodiment about 31 microns. For needleshift applications, the length of single-component fibers ranges from about 50 micrometers to about 125 micrometers, and in one embodiment is 75 micrometers. Multi-component binder fibers should not act as an auxiliary fuel source of open flames.

The binder fiber is a multi-component multi-bonding (mechanical and thermal bonding function) low melting point fiber which acts as a mechanical activator with sufficient adhesion to maintain the entanglement in the nonwoven fiber matrix, and as a binder for the thermal bonding required in the nonwoven. Can be. Representative multicomponent, multi-bond component fibers include fibers of a coextruded polymer of a combination comprising at least two of the following polymers: polyethylene terephthalate, polypropylene, polyethylene, low-density polyethylene, linear low-density polyethylene, poly Lactic acid, polytrimethylene terephthalate, polycyclohexanediol terephthalate, polyethylene terephthalate glycol, nylon 6, nylon 6,6, nylon 11, nylon 12, polymethyl pentene and others with sufficiently low melting points, inherent or modified Thermoplastic polymers. The term "sufficiently low" is synonymous with the preceding single-component fibers. Similar to single-component fibers, multi-component, multi-bond fibers provide thermal bonding and provide a soluble polymer; However, the second polymer does not melt and provides a mechanical function for fiber entanglement. This latter difference is the distinction between multi-component fibers and multi-component, multi-bond fibers.

In other words, the multi-component multi-bond fibers should comprise at least one component comprising a low-melting binder and a high melting point component that remains intact after heat exposure in the thermal bonding step. This final difference is the distinction between multi-component fibers and multi-component, multi-bond fibers.

Multi-component multi-bond fibers are included in at least 15 weight percent of the nonwoven fiber blend. In the present invention, when multi-component multi-bond fibers are used, it does not require the addition of other highly sticky fibers for mechanical fiber engagement after thermal bonding to meet all the depicted criteria.

The diameter of the multi-component multi-bond fibers ranges from about 20 microns to about 60 microns, in one embodiment 31 microns. The length of single-component fibers for needle punch applications ranges from about 50 millimeters to about 125 millimeters, and in one embodiment is about 75 millimeters. Multi-component multi-bonded fibers should not serve as an auxiliary fuel source for open flames and should be virtually flame resistant.

Multi-component, multi-bond fibers may have a variety of different fiber structures (e.g., sheath / core, eccentric sheath / core, side-by-side, bilateral). , Pie wedge, hollow pie wedge, iceland-in-the-sea or matrix structure), but it may be close to its original length after thermal bonding. Must have core fibers This remaining core fiber should not act as an auxiliary fuel source in the open flame and should have strength sufficient to maintain mechanical entanglement under stress. In one embodiment, at least about 10 percent, but not more than about 90 percent by weight, individual fibers should act as a thermal binder and have a melting point of at least about 107 ° C. and up to about 150 ° C. In another embodiment the melting point is about 110 ° C. The core fibers described above comprise at least about 10 weight percent, up to 90 weight percent of individual fibers, which must have a melting point of at least about 115 ° C.

Useful binder fibers are a core / cis bi-component structure comprising a polyethylene terephthalate (PET) core and a low melting PET sheath, the sheath of the individual fibers being about 60 weight percent and the remaining 40 percent being the core. The sheath acts as a thermal binder forming the outer surface of the binder fiber and has a melting point of about 110 ° C. and the core having a melting point of about 130 ° C. Such core / cis bi-component binder fibers are available from Huvis Corporation, Korea. In one embodiment, the core / cis bi-component binder fibers comprise from 50 to 65 weight percent of the fiber blend at the nonwoven barrier.

Other multi-component multi-bond fibers that may also be employed are fibers of a coextruded polymer of a combination comprising at least two of the following polymers: polyethylene terephthalate, polypropylene, polyethylene, low-density polyethylene, linear low-density polyethylene, Polylactic acid, polytrimethylene terephthalate, polycyclohexanediol terephthalate, polyethylene terephthalate glycol, nylon 6, nylon 6,6, nylon 11, nylon 12, polymethyl pentene, and sufficiently low melting points, inherent or modified Or other natural cellulose fibers (cotton, flax, ramie, jute, hemp, hemp, etc.) or protein fibers (wool, cashmere, camel hair, Mohair, hair of other animals, silk, etc.).

Such multi-component multi-bond fibers comprise one or more components comprising a low melting point binder and a high melting point component that remains intact after heat exposure in the thermal bonding step, similar to the multi-component, multi-bond fibers mentioned above. must do it. The binder may be a synthetic fiber having a melting point within the aforementioned range that serves as an auxiliary fuel source for open flames. The remaining core portion may be any synthetic or natural fiber having a melting point above 115 ° C., which does not act as an auxiliary fuel source for open flames and is sufficient to trap entanglement between fibers and maintain fiber web integrity after needling. Has fiber adhesion.

For the purposes of the present invention, the minimum Limiting Oxygen Index (LOI) of the fiber should be at least about 21 to be considered as a non-auxiliary fuel source. The LOI is a relative measure of flammability, determined by igniting the sample in an oxygen / nitrogen atmosphere and then adjusting the minimum amount of oxygen content required to maintain steady combustion. The higher the value, the less combustible the material is considered. The limit oxygen index (LOI), also called the critical oxygen index (COI) or oxygen index (OI), is defined as follows:

Where [O ₂ (concentration)] and [N ₂ ] are the concentrations of at least oxygen in the inlet gas and the nitrogen concentration in the inlet gas, respectively, required to pass the "minimum combustion length" criterion. If the injection gas is maintained at a constant pressure, the denominator of the equation is constant, and the decrease in the partial pressure (concentration) of oxygen will be balanced by the increase in the partial pressure (concentration) of the corresponding nitrogen. The marginal oxygen index is usually reported in percentage rather than fraction.

 Since air contains about 20.95% by volume of oxygen, any material with a lower limit oxygen index will burn easily in air. In contrast, the combustion behavior and propensity for flame propagation of polymers with a marginal oxygen index greater than 20.95 to be reduced or zero after removal of the ignition source. If LOI> 100, self-sustaining combustion is not possible, and that value is physically meaningless. Examples of values of LOI of various compounds are shown in Table 9 below.

Some examples of binder fibers commercially feasible in the practice of the present invention include the following special monopolymer fibers, all of which are readily available from Fiber Innovations Technology (FIT) of Tennessee, Johnson City, each product code Are shown in parentheses: for PETG binder fibers (unstretched, T-135), PETG binder fibers (stretched) (T-137), PCT (T-180), FR (inner flame) PET (T-190) and for spinning FR PET (T-191). Other examples of binder fibers include the following concentric sheath / core bi-component fibers, which are also available from FIT, with product codes indicated in parentheses: 110 ° C. “melt” CoPET / PET (T-201), 185 ° C melted CoPET / PET (T-202), down-gray version of T-201 (T-203), black version of T-202 (T-204), 13O ° C melted CoPET / PET (T-207), 15O ℃ Melt High Crystalline CoPET / PET (T-215), Black Version of T-215 (T-225), PCT / PP (T-230), PCT / PET (T-231), PETG / PET (T- 235), 185 ° C, High Tg coPET / PET (T-236), HDPE / PET (T-250), HDPE / PP (FDA Food Contact) (T-251), LLDPE / PET (T-252), PP / PET (T-260), nylon 6 / nylon 6,6 (T-270), and the black version of T-270 (T-271). Polyethylene terephthalate (PET) is particularly useful in the practice of the present invention, but there is a wide range of different binder fiber types.

Still other binder fibers available from FIT are PET (polyester), coPET, Tm = 110 ° C, coPET, Tm = 125 ° C, coPET, Tm = 18O ° C, coPET, Tm = 200 ° C, PLA (polylactic acid), Tm = 130 ° C, PLA, Tm = 150 ° C, PLA, Tm = 17O ° C, PTT (polytrimethylene terephthalate), PCT (polycyclohexanediol terephthalate), PETG (PET glycol), available under the trade names Corterra ^TM , HDPE (high density polyethylene), LLDPE linear low density polyethylene, PP (polypropylene), PE / PP copolymer, PMP (polymethyl pentene), nylon 6, nylon 6,6, nylon 11 and nylon 12.

In addition to those above, polyester binder fibers can be used in some cases. Examples of polyester binder fibers include those available from Wellman, Inc. of Fort Mill, South Carolina, under various types of names such as 209, H1305, H1295, H1432, M1440, M1429, M1427, M1425, M1428, and M1431. do.

In addition to the required amorphous silica fibers and the required binder fibers, the nonwoven composition may include up to 70 weight percent of other fibers that are considered as non-auxiliary fuel sources, namely complementary fibers. In the present invention, embodiments consisting of simple-thermal binder fibers, such as single component binder fibers comprising low melting polymers, require the addition of at least 15 weight percent of high tacky fibers to provide mechanical fiber engagement after thermal bonding. do. One embodiment of the present invention is a supplement such as about 35-50 weight percent amorphous silica, 50-65 weight percent binder fibers, and a solution dyed (colored) PET fibers for color in single layer nonwoven fire and thermal barrier fabrics. 5 to 10 weight percent of the fiber, wherein the binder fiber is a core / cis bi-component structure comprising a polyethylene terephthalate (PET) core and a low melting PET sheath.

Up to about 15 weight percent, in one embodiment up to about 10 weight percent, and in other embodiments up to about 15 weight percent supplemental fiber that is not considered a "non-assisted" fuel source (as defined above), that is, having a LOI of less than 21 It is possible to include up to 5 weight percent. However, such fibers employed would be limited in their application to the production of flame retardant fabrics or fire and heat resistant fabrics.

The present invention also allows to reduce the physical property direction bias, maintain the fuller length of the individual fibers, encapsulate and include the individual fibers, through some mechanical entanglement and additional thermal bonding of the web of fibers, A method of making a single layer nonwoven that can reduce the density per area of a nonwoven without significant loss of fabric integrity.

Nonwoven fabrics can be produced as follows. Combinations of the various fibers that can be employed in the present invention can be weighed and formed into a fibrous web, either dry or wet. The web can be formed in one of several different ways.

 1. Web formed by dry lamination, carding method

The bales of each fiber type are injected in a process that separates (opens) the clumps and bundles of fibers. Open fibers of each type are weighed in the process and injected together into a blended web laydown calculated as percent of total fiber type weight. This web laydown is then injected into a carding machine using a rotating cylinder and fine teeth to align the fibers in parallel alignment directions. This carded web can then be transferred directly to the bonding process or moved at the correct angle to allow the stacking of the carded web to be increased in web width, web weight, and / or diagonal strength before moving onto the bonding process. Overlaid on the conveyor.

2. Web formed by air laying method

A bale of each fiber is injected in the process of separating (opening) the clumps and bundles of the fiber. Each type of open fibers is weighed in the process and injected together into a blended web laydown calculated by the total fiber type weight percentage. This web laydown is formed by keeping the fibers in the air and then collecting them as a bat on a screen that separates the fibers from the air. Such webs are then placed cross-overlaid on conveyors moving at the correct angle allowing the stacking of faceted webs to increase the width and / or web weight of the webs before being transferred directly to the bonding process or transferred to the bonding process. .

In the present invention, a method useful for web formation is a dry laminated carding process.

Useful fabric formation is mechanical fiber entanglement by needlepunching the web and thermally bonding it by applying heat at temperatures below the melting point of the binder or below the melting point of the structural fibers mechanically bonded the fabric through the entanglement.

Although waterjets tend to be more damaging to amorphous silica fibers, which are more sophisticated than needlepunching, it is also possible to hydroentangle the fibers using high pressure waterjets.

Although one embodiment is a nonwoven with mechanically entangled and then thermally bonded fibers, it is also possible to blend the fibers into a woven structure and then thermally bond them. In woven fabrics, it is possible to employ amorphous silica fibers in the machine direction or in the cross machine direction in exchange for one or more FR or binder fibers. Optionally, the fibers can be replaced in the machine direction to be woven with amorphous or FR or binder fibers in the cross machine direction. In percent, the woven fabric according to the present invention may comprise the aforementioned compositions for blending amorphous silica and FR fibers as well as amorphous silica and binder fibers. In particular the interwoven structure of the open weave fabric is not a limitation of the present invention and therefore encompasses the full range of end counts in the machine and transverse machine directions.

Blends in woven fabrics are possible through various yarn structures ("type" = fiber type for the blend):

One) cinnabar :

a) Blending various types of short fibers before spinning them with successive yarns.

b) Blending multiple types of continuous filaments before engaging or twisting them with continuous yarns.

2) Fold / Carding Yarn:

a) Twisting two or more different types of single yarn together into a resultant ply yarn.

b) Combining two or more different types of twisted yarn into resultant cotton yarn.

3) core-spoon / Wrapped  four:

a) The core of a different type of fiber wrapped around it, or the core of a combustible continuous yarn or filament, resulting in one fiber type as a core and another type of continuous yarn forming an outer layer.

Woven blends are possible through the woven structure of yarns of different fiber types.

1) Wefts may be of some type and warps may be of different types.

2) Yarns of different fiber types can be combined into wefts at regular intervals.

3) Yarns of different fiber types can be joined to warp at regular intervals.

4) Yarns of different fiber types can be combined in both weft and warp directions.

The present invention provides a fabric useful for protecting an item or product, such as a mattress, from fire and associated heat; A method of making a fabric; And processes for protecting materials in products using fire and heat barrier fabrics. Such a process for protecting materials in products using fire and thermal barriers is to ultrasonically bond or ultrasonically bond the barrier fabric directly to at least one component also present in the product. Components containing materials susceptible to damage due to fire and heat when exposed to open flames require barrier protection. Ultrasonic coupling is well known in the art, but the ability to incorporate it directly into the fire and heat barriers as quasi-assemblies is novel. Ultrasonic bonding uses ultrasonic energy to connect layers of thermoplastic materials. High speed ultrasonic vibrations result in bonding between thermoplastic materials that fuse the materials together. Such fusion, or bonding, requires similar thermoplastic materials to form the bond.

For example, many traditional mattress structures have a high-loft fiber batt between the outer layer of the ticking fabric and the inner layer of the lightweight fabric (typically spunbond) to maintain the stitching of the needle-and-thread quilted assembly. Surface is covered by the assembly. The quilted assembly forms a soft and visually appealing surface because of the lofty quilted pattern. Since high-loft fiber batts are typically PET, it is also possible for both outer teaking layers and inner structural layers to use PET or main-blend PET such as these and similar assemblies or products, for example , Furniture, transport seats and surfaces, bedding and the like are sometimes quilted by ultrasonic coupling means, rather than by traditional needle-and-sewn quilting.

The use of ultrasonic bonding for the production of quilted assemblies has advantages over traditional sewing methods, which allow for high throughput rates, low raw materials required (no threads), and low mechanical wear (spinning of needles). No load; fewer moving parts), and also using ultrasonic coupling can form a better interlayer bond that is comparable to the stitched seams of traditional quilting or better.

Many of the materials and material blends that can form a suitable flame and thermal barrier are not thermoplastic and differ significantly from the other thermoplastic components used in the final product. Therefore, as the demand for products meeting new open flame needs increases, there is no possibility of using ultrasonic coupling for quilting.

As a result of the present invention the blend of fabrics permits ultrasonically coupled quilting of assemblies comprising flame and thermal barriers. Within the depicted range of the blend, blends comprising at least 40 weight percent PET or other suitable thermoplastics are suitable for ultrasonic coupling of the same or similar thermoplastics to other materials comprising at least 40 percent. In one embodiment the flame and heat barrier fabric comprises at least 50 weight percent PET and the other layers of the assembly comprise at least 50 weight percent PET or similar thermoplastic.

The mattress structural assembly can be made of any number of the following structures (inner layers are not necessary).

1. The flame and thermal barrier fabric can be ultrasonically bonded to the outer ticking layer along the length of the assembly and across the entire width.

2. The flame and thermal barrier fabric can only be ultrasonically combined with the outer ticking layer in position along the edge of the assembly.

3. For the added softness and depth of the quilted pattern along a flat surface called "pop" in the mattress industry, the layer (s) of the high-loft batt are flamed prior to bonding as mentioned in 1 above. And between thermal barrier fibers and ticking.

4. For additional softness along the flat surface, a layer (s) of high-loft batt can be added between the flame and thermal barrier fabric and teaking prior to bonding as described in 2 above.

5. The structure outlined in items 2 and 4 above allows for improved flame and thermal protection, since the body of the barrier fabric does not contain a bond point. The nature of the ultrasonic coupling requires pressure between the horn and the anvil. This causes compression of the layers at each point of attachment, and these compressed points typically cause a lot of thermal transfer through the materials and cause a weakened wet strength of the materials when exposed to an open flame. If a smooth surface result from assembly structures 2 and 4 is not required, then the high-loft batt or other loft fabric may be applied to 1 and 3 before the flame and thermal barrier fabric is continuously ultrasonically bonded at points along the assembly edge as an inner layer. It is shown that it can be ultrasonically coupled directly to the outer ticking layer in the depicted manner.

6. Modifications of structure 3 that provide the same or similar effect are possible by laminating the flame and thermal barrier fabric directly to the teaking layer, and the high-loft batt laminated inside before being ultrasonically bonded as described in 1 above. do.

7. Modifications of structure 4 that provide the same or similar effect are possible by directly laminating the flame and thermal barrier fabrics into the teaking layer, and the high-loft batt is laminated internally prior to ultrasonic bonding as depicted in 2 above. do.

Other products used to make mattresses are border fabrics or side fabric materials. For example, satisfactory border assemblies for mattresses and / or box springs may be made of any of the above structures using full width roll-excellent materials of approximately 120-inch or less in width (ultrasound horns and anvils). Theoretically there is no limit to the width because it can be arranged in a format, but in practice, the width is limited by the width of the roll-excellent ticking and high-loft batts currently available as well as the support equipment currently available). The body quilt pattern is ultrasonically coupled using a series of wide horns applied across the width of the patterned cylinder anvil. Typical widths for the border assembly range from about 9 inches to about 14 inches (or more). These individual widths may be edges sealed with a stitch pattern (or other pattern) by ultrasound using an in-line or off-line series of ultrasonic slits and ultrasonic horns and slitter / sealing anvils.

The fabric of the present invention is particularly useful as a mattress border because the mattress, underneath the top of the panel, does not require a comfort that is incorporated into the bets to provide softness and loft to the panel. Thus, in the border, the FR fabric is easily bonded to the teak by ultrasonic bonding to form a finished product, a product that can be thought of as a subassembly of a mattress.

The process setup for ultrasonic closure can employ a 1.1 kW power supply in a series of 9-inch horns across the width of the patterned cylinder anvil with the quilting design required for the body of the assembly. After the layers have been injected and unwound at this location in the process, additional layers are used (if necessary) with a 1.1 kW power supply for each horn, one inch diameter placed at the required width of the slit and sealed border assembly at the same time. Before flowing through a series of horns, it can be introduced if desired. Process variables such as pressure, speed, size, power booster and loading differ based on the type and mass of the material used.

In order to demonstrate the utility of the fabric according to the invention, many fabric samples were subjected to open flame tests to determine their relative resistance to fire and its associated heat, which in turn is the ability to provide protection to the item. It should be noted that testing of protected items is often time specific to the end-use application of the protected item, and that the test includes the item as a whole rather than a test for each of the components that make up the item. Testing of fabrics as a component to predict or correlate results in the final item usually differs between the manufacturers of the item. Preliminary tests were performed on a variety of barrier fabrics covering a range of amorphous silica to binder fiber ratios. As a result of this screening, it was determined that for use for the mattress, a 40 percent amorphous silica content that is well balanced with the required cost for barrier protection is useful. Nevertheless, higher or lower amounts of amorphous silica can be used in other environments (products) where the barrier property requirements may be different so that the cost allowed to produce the fabric is acceptable. Such other uses are discussed below.

Proprietary tests were conducted to establish baselines of performance and track progress against the baselines for the development of the fire and thermal barrier fabrics of the present invention for use in the mattress industry. Although the specificity of the test is reliable by independent laboratories, it may be revealed that the test is based on open flames in contact with the fabric surface for a defined period of time. After the open flame is removed, the fabric is allowed to continue burning until it is completely extinguished. The maximum temperature is measured on the opposite side of the flame over the length of the test. The mass of the sample is measured before and after exposure to the flame to calculate the mass loss. The strength of the fabric at the point of exposure was tested to determine the retention or wet strength. (Depending on the application, this may be tension, sting, cracking or other things). The test results are reported in Table 10 below:

Although the nature of the test is proprietary, its shared results demonstrate the performance of the present invention, amorphous silica blends over other flames and thermal barriers when exposed to open flames, "mass per unit area," "maximum temperature. "," Percent Mass Loss "values are the average of six specimens tested for each blend or product. Tests conducted in an independent hap have generally established a baseline of performance for products in use as flame and thermal barrier fabrics in the mattress industry (“Incumbent Market Product”, Examples 54-56). Although these results are not directly related to the performance of the tested bedding set according to the above mentioned TB603 California Open Flame Criteria, nevertheless, the results are exposed to open flames without excessive thermal transfer and excessive mass loss through the fabric. Indicates the ability of the component fabric to prevent.

While "excess" may vary between mattress manufacturers, this kind of test allows a direct comparison of candidate fabrics to the standing component fabrics tested over a wide range in the final bedding set. The fabrics tested included ten example (54-63) fabrics other than the present invention followed by eleven example (64-74) fabrics according to the present invention. Referring to the data in Table 10, it is shown that the use of barrier fabrics comprising 40 percent of amorphous silica provides acceptable protection compared to current products. While Examples 66 and 67 show a high percentage of mass loss, it should be noted that this is due to the lower mass per unit area (4.9 and 4.7) compared to other fabrics. Example 73 also shows greater maximum temperature and mass loss, which is a supplementary fiber, 8 percent PP fiber, that is a fuel source, ie, not a "non-contributing" fuel source, applied to provide colored or dyed fabrics. Because of its existence.

In view of the foregoing disclosure, it can be appreciated that the FR fabrics of the present invention can be finally used in a variety of items, including the following.

1. Bedding—a barrier exposed under the ticking or on the top and / or bottom of the bottom of a mattress or box spring. Borders, as discussed above, are also products that can benefit from the presence of barriers.

2. Furniture-Barriers exposed to the underside or other invisible face of the furniture or under the decoration of the furniture.

3. Carriage-barriers exposed behind the ornaments of the seat or on the top or other invisible face of the seat, behind the wall covering the material or attached in or behind the curtain or pavement layer. Lining for the bay or cotton of the engine and luggage that needs to be protected from extreme heat.

4. Bedding-laminated in blankets, thick comforters, pillows, etc.

5. Clothing-Laminated in personal protective clothing to protect against flames and heat. Uses include items such as coats, pants, gloves and boots, including firefighters, soldiers, astronauts, industrial forces, and experimenters.

6. Automotive—Inner lines of engine bays, pipe sheaths, in-seat, and barriers behind carpeting, and decorated surfaces.

7. Construction / House / Industrial-house warp, interior wall protection, fire blankets, lining of storage areas for flammables, junction packaging, landfills and lining where potentially flammable gases may be released, hot gas Filtration, scatter rugs and lining materials for carpets, pot holders and gloves in the kitchen.

The present invention therefore encompasses all of the above products made by the process of the present invention.

Therefore, there is evidence that the use of amorphous silica fibers is very effective in providing FR blends and fabrics. The present invention may be practiced in combination with amorphous silica fibers in combination with at least one other flame retardant fiber or binder fiber which is essentially limited thereto. If one or more selected can be combined with amorphous silica, implementation is not limited to the selection of a particular FR fiber or binder fiber. The fiber blends of the present invention can be used to make flame retardant fibers for a variety of purposes, including but not limited to barrier fabrics for decorative, bedding, and bedding applications. In addition, the fabric is not limited to the nonwoven type.

Based on the foregoing, it is now clear that the use of the fiber blends described herein is novel and will provide barrier fabrics and flame resistant fabrics as described herein. Therefore, it is to be understood that obvious variations are within the scope of the claimed invention, and therefore, the choice of particular component elements may be determined without departing from the spirit of the invention mentioned and described herein. Therefore, the scope of the present invention shall include all modifications and variations that fall within the scope of the appended claims.

Claims (92)

Amorphous silica fibers; And One or more fibers selected from the group consisting of flame retardant (FR) fibers, binder fibers, and mixtures thereof Flame retardant (FR) fiber mixture comprising a. The method of claim 1, wherein the FR fibers are modacrylic, polyester with phosphalane, melamine, meta-aramid, para-aramid, polybenzimidazole, polyimide, polyamideimide, partially oxidized poly Acrylonitrile, novoloids, poly (p-phenylene benzobisoxazole), poly (p-phenylenebenzothiazole), polyphenylene sulfide, flame retardant viscose rayon, aluminosilicate-modified silica A fiber mixture selected from the group consisting of viscose rayon, cellulose compounds, polyetheretherketones, polyketones, polyetherimides, natural or synthetic fibers coated with FR resin, and mixtures thereof. The fiber mixture of claim 1, wherein the fiber mixture comprises at least 5% by weight of amorphous silica fibers based on the total weight of fibers in the fiber mixture. The fiber mixture of claim 3, wherein the fiber mixture comprises 5 to 65 wt% amorphous silica fibers, and 35 to 95 wt% FR fibers. The fiber mixture of claim 2 comprising amorphous silica fibers, modacrylic fibers, and FR rayon fibers. The fiber mixture of claim 2 comprising amorphous silica fibers, modacrylic fibers, and viscose rayon fibers. The fiber mixture of claim 2 comprising amorphous silica fibers, modacrylic fibers, and cellulose fibers. The fiber mixture of claim 2 comprising amorphous silica fibers, and FR rayon fibers. The fiber mixture of claim 2 comprising amorphous silica fibers, modacrylic fibers, viscose rayon fibers and FR polypropylene fibers. The method of claim 1, wherein the binder fibers are selected from the group consisting of single-component fibers, multi-component fibers, multi-component, multi-bond fibers and complementary fibers, the fibers having a melting point of at least 107 ° C. Fiber mixture. 11. The method of claim 10 wherein the single-component fiber, multi-component fiber, and multi-component, multi-bond fiber exhibit thermal bonding properties, wherein the multi-component, multi-bond fiber and the supplemental fiber additionally Fiber mixtures that provide strength properties. The fiber mixture of claim 10, wherein the fiber mixture comprises at least 15% by weight of amorphous silica fibers based on the total weight of fibers in the fiber mixture. The method of claim 12 wherein the fiber mixture is 15 to 80% by weight of amorphous silica fiber, 15 to 85% by weight of binder fibers, and Up to 70% by weight of supplemental fiber to add up to 100% by weight in total Fiber mixture comprising a. The method of claim 13 wherein the fiber mixture is 15 to 80% by weight of amorphous silica fiber, 15 to 85% by weight of the single-component binder fiber, and 15% or more by weight supplement fiber Fiber mixture comprising a. 12. The method of claim 11 wherein the single component binder fibers are low melting polyethylene terephthalate, polypropylene, polyethylene, low density polyethylene, linear low density polyethylene, polylactic acid, polytrimethylene terephthalate, polycyclohexanediol terephthalate, polyethylene terephthalate glycol , Nylon 6, nylon 6,6, nylon 11, nylon 12, and polymethyl pentene. The method of claim 11 wherein the multicomponent binder fibers are polyethylene terephthalate, polypropylene, polyethylene, low-density polyethylene, linear low-density polyethylene, polylactic acid, polytrimethylene terephthalate, polycyclohexanediol terephthalate, polyethylene tere A fiber mixture comprising fibers of a coextruded polymer of a combination comprising at least two polymers selected from the group consisting of phthalate glycol, nylon 6, nylon 6,6, nylon 11, nylon 12, and polymethyl pentene. 12. The method of claim 11, wherein the multi-component, multi-bond binder fibers are concentric sheath / core, eccentric sheath / core, side-by-side with core fibers that do not change in length after thermal bonding; side-by-side bilateral, pie wedges, hollow pie wedges, Iceland-in-the-sea or matrix structures and these Fiber mixture is selected from the group consisting of. 18. The method of claim 17, wherein the multi-component, multi-bond binder fibers are polyethylene terephthalate, polypropylene, polyethylene, low-density polyethylene, linear low-density polyethylene, polylactic acid, polytrimethylene terephthalate, polycyclohexanediol Terephthalate, polyethylene terephthalate glycol, nylon 6, nylon 6,6, nylon 11, nylon 12, and polymethyl pentene, comprising fibers of a coextruded polymer of a combination comprising two or more polymers selected from the group consisting of With fiber mixture; Wherein said multi-component, multi-bond fiber comprises at least one component comprising a low melting polymer and a high melting polymer that remains intact after being exposed to sufficient heat to melt. 19. The core / sheath bi-component structure of claim 18, wherein the multi-component, multi-bond binder fibers are a core / cis bi-component structure comprising a polyethylene terephthalate (PET) core and a low melting PET sheath, wherein the sheath is based on the weight of the individual fibers. 60% and the core is the remaining 40%. The method of claim 11, wherein the supplementary fiber is polyethylene terephthalate, polypropylene, polyethylene, low-density polyethylene, linear low-density polyethylene, polyacetic acid, polytrimethylene terephthalate, polycyclohexanediol terephthalate, polyethylene terephthalate Coated with fibers of the coextruded polymer of a combination comprising two or more polymers selected from the group consisting of glycol, nylon 6, nylon 6,6, nylon 11, nylon 12, and polymethyl pentene, and any of the aforementioned polymers Natural cellulosic fibers and protein fibers, or joined together, wherein the multicomponent, multi-bond fibers comprise a low melting polymer and a high melting polymer that remains intact after exposure to sufficient heat to melt the low melting polymer A fiber mixture comprising at least one component. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

Images