HK1072084B

HK1072084B - Nonwoven highloft flame barrier

Info

Publication number: HK1072084B
Application number: HK05104946.2A
Authority: HK
Inventors: D．L．马特; A．C．翰得曼恩
Original assignee: 巴索菲尔纤维有限责任公司
Priority date: 2001-09-12
Filing date: 2002-09-11
Publication date: 2009-05-15

Description

Nonwoven high loft flame barrier

Technical Field

The present invention relates to a nonwoven high loft flame barrier well suited for use in mattress, upholstered furniture, fiber-filled bed coverings and transportation seating applications or any end use application where a high loft nonwoven material is desired for flame barrier purposes. Preferred nonwoven high loft flame barriers of the present invention comprise a blend of: fibers comprising "class 1" fibers that are inherently flame resistant and resistant to shrinkage by direct flame, melamine fibers, preferably alone or in combination with: other inherently flame resistant "category 1" fibers, "category 2" fibers prepared from polymers prepared with halogenated monomers, and preferably additional fibers such as low melt binder fibers, which are thermally activated in a high loft manufacturing process to provide low bulk density, resilience, and thermal insulation properties in the end use application. Polymers prepared with halogenated monomers produce oxygen-depleted gases when exposed to flame temperatures. These oxygen-depleted gases help prevent spontaneous ignition of decomposition products from, for example, the lower layers of polyurethane foam, and they also help to extinguish residual flames that may emanate from overlying clothing cover fabrics and the like. The oxygen-depleted gas from the polymer prepared with the halogenated monomer also covers and protects the carbon-containing char formed during the decomposition of the inherently flame-retardant fibers, thereby providing significantly longer time before the char breaks when exposed to air at open flame temperatures. These synergistic blends can then withstand extended periods of time with minimal shrinkage of the char shield, thereby preventing flames from "breaking through" the char shield and igniting the underlying material. Other component fibers such as: natural fibers to improve product economics in end-use applications. The high loft shield of the present invention may also be used to make open flame resistant composite articles while also allowing for continued use of conventional non-flame resistant garment cover fabrics, conventional non-flame resistant fibrous fillers, conventional non-flame resistant polyurethane foams, and the like.

Background of the related art

It is known in the textile industry to produce fire resistant products for use in upholstery furniture, mattresses, pillows, bedspreads, duvets, quilts, mattress pads, automobile seating, public transportation seating, aircraft seating, and the like, using woven, needle punched or spunlaced (spunlace) nonwoven fabrics or braids formed from natural or synthetic fibers and then treating these fabrics with fire retardant chemicals. Conventional Flame Retardant (FR) chemicals include halogen-based, phosphorus-based, and/or antimony-based chemicals. Unfortunately, the fabrics so treated are heavier than similar types of non-flame resistant fabrics and have a reduced wear life. Although FR chemically treated fabrics self-extinguish and exhibit limited melting behavior when the flame is removed, they do not perform well as flame barriers even in a short period of time when they are subjected to a large direct flame attack. Typically after a short exposure to direct flame, FR chemically treated fabrics form brittle char, shrink and crack. This exposes the underlying material (e.g., polyester fiber filler and/or polyurethane foam) in the composite article to an open flame. The cracking and shrinking behavior of this fabric can cause ignition of the underlying material. When these fabrics prepared with FR treated cotton, FR polyester and other FR treated fabrics are used in composite articles such as upholstered furniture and mattresses, these composite articles are considered unsuitable for passing more stringent open flame tests such as: california Test Bulletin 133(1 month 1991) (Cal TB133), California Test Bulletin 129 "method for flammability testing of mattresses in public buildings" (10 months 1992) (Cal TB129) and British Standard 5852-Crib5 (8 months 1982) (BS 5852).

Some currently used flame barrier fabrics that are targeted to pass more stringent open flame tests, such as Cal TB129 and Cal TB133, include:

1) woven polymer coated 100% glass fiber flame barrier: (Fabric，Sandel International Inc.)

2) Woven or braided core spun yarn-based flame barriers in which natural and/or synthetic fibers are wrapped around a multifilament fiberglass core and then optionally treated with a coating of FR chemicals, and/or thermoplastic polyvinyl halide compositions, such as polyvinyl chloride: (Seat cushion shield, Intek;card products, Chiquola Fabrics, LLC)

3) Nonwoven hydroentangled spunlaced flame barrier (thermalblock) consisting of 100% para-aramid^TMZ-11，DuPont Company)。

4) Woven or braided core-spun yarn-based flame barriers in which natural and/or synthetic fibers are wrapped around multifilament and/or spun para-aramid core yarns and then optionally treated with FR chemicals, and/or coatings of thermoplastic polyvinyl halide compositions, such as polyvinyl chloride (R) ((R))Seat cushion shield, Intek;brand product, chiquola fabrics, LLC).

Drawbacks of the above-described flame barrier solutions for more severe open flame applications in mattresses, upholstered furniture and other fiber-filled applications include:

a) woven flame barriers, particularly when coated with FR materials, impart a stiff "hand" to the composite article, which negatively impacts the feel of the final product.

b) During manufacture, prior art woven, non-woven and braided flame shields must be laminated to decorative fabrics or double-sided decoration. This increases the number and complexity of the clothing cover fabric, thereby increasing manufacturing costs.

c) 100% fiberglass flame shields have poor durability due to glass-to-glass abrasion.

d) Woven and braided flame shields made by winding core spun yarn with natural fibers must be constructed in a high weight configuration (i.e., -10 opsy or 336 g/m)²) Are manufactured as effective flame barriers and may negatively affect the feel of the composite article.

e) Natural fiber wrapped core spun yarn fabrics require additional FR chemical treatment and/or coating of thermoplastic polyvinyl halide compositions, such as polyvinyl chloride, to effectively pass the more stringent open flame test. This negatively impacts the workplace by having to handle these chemicals, and this increases the exposure of the chemicals to the consumer using the composite article.

f) Hydroentangled nonwoven spunlace flame barriers comprising significant amounts of para-aramid fibers impart a yellow color to the flame barrier and negatively impact the appearance of the composite article, particularly when used directly under white or light colored decorative upholstery and/or bedding cover fabrics.

g) Woven and braided flame shields add significant cost to the composite article since they require a yarn formation step, which is eliminated in the formation of the nonwoven flame shields of the present invention.

Summary of The Invention

To overcome or significantly improve the disadvantages of the related art, it is an object of the present invention to provide a nonwoven high loft flame barrier that is capable of passing stringent open flame testing. In its preferred usage in this application, the term "flame barrier" means a product incorporated into a composite article such that when tested using composite type testing methods, such as california test publication 129(Cal TB129) for mattresses and california test publication 133(CalTB133) for upholstered furniture, the flame barrier allows the continued use of conventional materials such as clothing apparel fabrics, fiber fillers and polyurethane foams while still passing these stringent large open flame tests. It will be appreciated by those skilled in the art that the flame barrier of the present invention comprised of the fiber blend, even at overall lower basis weights, can still pass less stringent open flame tests, such as the small open flame test.

In its preferred usage in this application, the term "high loft" refers to (i) a lofty, relatively low density nonwoven fibrous structure, preferably having a greater volume of air than the fibers; (ii) the purpose is to create a nonwoven material that is produced with bulk or thickness without added weight; and/or (iii) nonwoven fibrous products that are not compacted or purposefully compressed within a significant portion of the product during the manufacturing process. Hair brushThe basis weight of the high loft nonwoven material is preferably 75 to 600g/m²More preferably 150-450g/m²And even more preferably, for many intended uses, 300-375g/m². The high loft nonwoven material of the present invention also preferably has a thickness of 6mm to 75mm, and a thickness range of 7 to 51mm is believed to be well suited for many uses of the present invention. Since having too low a basis weight for a given thickness at the higher end of the above thicknesses may in some cases degrade the shielding effect, it may be desirable for some applications to use the lower end basis weight value in combination with the lower end thickness range, while the higher end basis weight is generally not considered as such. Therefore, 75g/m²The basis weight of (a) and a bulk or thickness range of 6mm to 13mm, or 150g/m²The basis weight of (a) and a bulk or thickness range of 6mm to 25mm, or 300g/m²The basis weight of (a) and a bulk or thickness range of 10mm to 50mm, or 450g/m²The basis weight of (a) and a bulk or thickness range of 20mm to 60mm, or 600g/m²Combined with a bulk or caliper range of 19mm to 75mm, represents a preferred basis weight/caliper under the present invention. Further preferred combinations include, for example, a basis weight of 150g/m²(with a preferred thickness or loft range of 7mm-25 mm) -450g/m²(with a preferred thickness or loft range of 25mm to 51 mm). Further preferred combinations considered well suited for many of the intended uses of the present application, including flame barriers for bedding related products, include 300g/m²(with preferred thickness or bulk range of 20mm-35 mm) -375g/m²(with a preferred thickness or loft range of 25mm-50 mm) weight/thickness. Depending on the required flame barrier requirements and the desired use, the above thickness ranges show preferred ranges relative to the basis weight which is well suited for the typical intended use of the invention, but thickness levels above and below the ranges are also possible relative to the basis weight and vice versa.

Thus, according to the invention, 5Kg/m³-50Kg/m³Or more preferably 6Kg/m³-21Kg/m³And even more preferably 7.5Kg/m³-15Kg/m³Is well suited for the flame barrier purposes of the present invention.

The preferred denier of the fibers used in the nonwoven fiber blends of the present invention is preferably from 0.8 to 200 dtex, with ranges of 0.9 to 50 dtex and 1 to 28 dtex being well suited for many applications of the present invention, such as in conjunction with mattresses.

It is a further object of the present invention to provide composite articles such as mattresses and/or upholstered furniture products made with a nonwoven high loft flame barrier that passes more stringent open flame tests such as Cal TB133 and Cal TB129 versus mattresses alone (no substrate such as box spring).

The nonwoven high loft flame barrier of the present invention forms a thick, flexible char when directly exposed to flame and high heat, while having essentially no shrinkage in the x-y plane (e.g., "BASOFIL" melamine materials themselves comprise a shrinkage rate of less than 1% for 1 hour at 200 ℃). Such char is formed to prevent cracking of the flame barrier, for example, to prevent exposure of the underlying layers of fiber-filled batting and/or foam in the composite article to direct flame and high heat. The thick flexible char also helps to block the flow of oxygen and volatile decomposition gases while slowing heat transfer by creating an effective thermal barrier. The char formation behavior of the preferred fiber blends in the nonwoven high loft flame barrier considerably extends the time for the underlying material to decompose and ignite by generating oxygen-depleting gases that do not allow the volatile decomposition vapors of, for example, polyurethane to self-ignite and also aid in the self-extinguishment of the "surface" flame present.

According to a preferred embodiment of the present invention, a thermally bonded nonwoven high loft flame barrier, e.g., for mattress, upholstered furniture, fiber-filled bed coverings, and transportation seating applications, is produced by preparing an intimate staple fiber blend from categories 1 and 2, optionally incorporating fibers of any or all of categories 3, 4, and 5. Optional addition of a class 6 binder resin is also possible, such as in place of or in addition to the class 3 material.

Class 1: inherently flame retardant fibers such as: melamine, meta-aramid, para-aramid, polybenzimidazole, polyimide, polyamideimide, partially oxidized polyacrylonitrile, novoloid, poly (p-phenylene benzobisoxazole), poly (p-phenylene benzothiazole), polyphenylene sulfide, flame retardant viscose rayon (e.g., silica containing 30% aluminosilicate modification, SiO, etc.)₂+Al₂O₃Viscose rayon-based fibers), polyetheretherketone, polyketone, polyetherimide, and combinations thereof.

The melamine described above is an example of a class 1 fiber that is inherently flame retardant and exhibits substantially no shrinkage in the X-Y plane when subjected to an open flame. Melamine fibers are sold, for example, under the trade name BASOFIL (BASF A.G). Melamine resin fibres for use in connection with the present invention may be prepared, for example, by the methods described in the following documents: EP-A-93965, DE-A-2364091, EP-A-221330 or EP-A-408947, which are incorporated herein by reference. For example, a preferred melamine resin fiber comprises as monomeric building block (a) a 90 to 100 mol% mixture consisting essentially of: 30 to 100 mol%, preferably 50 to 99 mol%, particularly preferably 85 to 95 mol%, in particular 88 to 93 mol%, of melamine and 0 to 70 mol%, preferably 1 to 50 mol%, particularly preferably 5 to 15 mol%, in particular 7 to 12 mol%, of substituted melamine I or of a mixture of substituted melamines I.

As further monomeric building blocks (B), particularly preferred melamine resin fibers comprise from 0 to 10 mol%, preferably from 0.1 to 9.5 mol%, in particular from 1 to 5 mol%, of phenol or phenol mixtures, based on the total number of moles of monomeric building blocks (A) and (B).

Particularly preferred melamine resin fibres can generally be obtained by reacting components (A) and (B) with formaldehyde or a formaldehyde donating compound in a molar ratio of melamine to formaldehyde of from 1: 1.15 to 1: 4.5, preferably from 1: 1.8 to 1: 3.0, followed by spinning.

Suitable substituted melamines of the formula I

Is, wherein x¹，x²And x³Are each selected from-NH₂、-NHR¹and-NR¹R²But x¹，x²And x³Must not all be-NH₂And R¹And R²Each selected from hydroxy-C₂-C₁₀-alkyl, hydroxy-C₂-C₄-alkyl- (oxa-C)₂-C₄-alkyl groups)_nWherein n is 1-5, and amino-C₂-C₁₂-an alkyl group.

hydroxy-C₂-C₁₀The alkyl group is preferably hydroxy-C₂-C₆Alkyl radicals, such as the 2-hydroxyethyl, 3-hydroxy-n-propyl, 2-hydroxyisopropyl, 4-hydroxy-n-butyl, 5-hydroxy-n-pentyl, 6-hydroxy-n-hexyl, 3-hydroxy-2, 2-dimethylpropyl radical, preferably the hydroxy-C radical₂-C₄Alkyl radicals, such as the 2-hydroxyethyl, 3-hydroxy-n-propyl, 2-hydroxyisopropyl and 4-hydroxy-n-butyl radical, particularly preferably the 2-hydroxyethyl or 2-hydroxyisopropyl radical.

hydroxy-C₂-C₄-alkyl- (oxa-C)₂-C₄-alkyl groups)_nPreferably, n is 1 to 4, particularly preferably n ═ 1 or 2, such as 5-hydroxy-3-oxapentyl, 5-hydroxy-3-oxa-2, 5-dimethylpentyl, 5-hydroxy-3-oxa-1, 4-dimethylpentyl, 5-hydroxy-3-oxa-1, 2, 3, 4, 5-tetramethylpentyl, 8-hydroxy-3, 6-dioxaoctyl.

amino-C₂-C₁₂The alkyl group is preferably amino-C₂-C₈Alkyl radicals, such as 2-aminoethyl, 3-aminopropyl, 4-aminobutyl, 5-aminopentyl, 6-aminohexyl, 7-aminoheptyl, and also 8-aminooctyl, particularly preferably 2-aminoethyl and 6-aminohexyl, very particularly preferably 6-aminohexyl.

Substituted melamines particularly suitable for the present invention include the following compounds:

2-hydroxyethylamino-substituted melamines such as

2- (2-hydroxyethylamino) -4, 6-diamino-1, 3, 5-triazine,

2, 4-bis (2-hydroxyethylamino) -6-amino-1, 3, 5-triazine,

2, 4, 6-tris (2-hydroxyethylamino) -1, 3, 5-triazine,

2-hydroxyisopropylamino-substituted melamines, e.g. melamine

2- (2-hydroxyisopropylamino) -4, 6-diamino-1, 3, 5-triazine,

2, 4-bis (2-hydroxyisopropylamino) -6-amino-1, 3, 5-triazine,

2, 4, 6-tris (2-hydroxyisopropylamino) -1, 3, 5-triazine,

5-hydroxy-3-oxapentylamino-substituted melamines such as

2- (5-hydroxy-3-oxapentylamino) -4, 6-diamino-1, 3, 5-triazine,

2, 4, 6-tris (5-hydroxy-3-oxapentylamino) -1, 3, 5-triazine,

2, 4-bis (5-hydroxy-3-oxapentylamino) -6-amino-1, 3, 5-triazine and

also 6-aminohexylamino-substituted melamines, e.g.

2- (6-aminohexylamino) -4, 6-diamino-1, 3, 5-triazine,

2, 4-bis (6-aminohexylamino) -6-amino-1, 3, 5-triazine,

2, 4, 6-tris (6-aminohexylamino) -1, 3, 5-triazine or mixtures of these compounds, for example mixtures of the following: 10 mol% 2- (5-hydroxy-3-oxapentylamino) -4, 6-diamino-1, 3, 5-triazine, 50 mol% 2, 4-bis (5-hydroxy-3-oxapentylamino) -6-amino-1, 3, 5-triazine and 40 mol% 2, 4, 6-tris (5-hydroxy-3-oxapentylamino) -1, 3, 5-triazine.

Suitable phenols (B) are phenols containing one or two hydroxyl groups, e.g. unsubstituted phenols, selected from C₁-C₉Phenols substituted by alkyl and hydroxy groups, and also C substituted by two or three phenol groups₁-C₄-alkanes, bis (hydroxyphenyl) sulfones or mixtures thereof.

Preferred phenols include phenol, 4-methylphenol, 4-tert-butylphenol, 4-n-octylphenol, 4-n-nonylphenol, pyrocatechol, resorcinol, hydroquinone, 2-bis (4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, with phenol, resorcinol and 2, 2-bis (4-hydroxyphenyl) propane being particularly preferred.

Formaldehyde is generally used in the form of an aqueous solution having a concentration of, for example, 40 to 50% by weight, or in the form of a compound which provides formaldehyde during the reaction with (a) and (B), for example in the form of oligomeric or polymeric formaldehyde in solid form, such as paraformaldehyde, 1, 3, 5-trioxane or 1, 3, 5, 7-tetraoxane.

Particularly preferred melamine resin fibres are usually produced by polycondensing melamine, optionally substituted melamine and optionally phenol, together with formaldehyde or a formaldehyde donating compound. All the components may be present from the beginning or they may be reacted in small amounts and gradually at the time, while the polycondensate obtained is subsequently mixed with further melamine, substituted melamine or phenol.

Polycondensation is generally carried out in the conventional manner (cf. EP-A-355760, Houben-Weyl, volume 14/2, page 357 and the following pages).

The reaction temperature used is generally from 20 to 150 ℃ and preferably from 40 to 140 ℃.

The reaction pressure is generally not critical. The reaction is generally carried out in the range of 100-500kPa, preferably at atmospheric pressure.

The reaction may be carried out with or without a solvent. If an aqueous formaldehyde solution is used, typically no solvent is added. If formaldehyde is used in solid form, water is generally used as solvent, the amount used generally being from 5 to 40% by weight, preferably from 15 to 20% by weight, based on the total amount of monomers used.

In addition, the polycondensation is generally carried out in a pH range of greater than 7. A pH range of 7.5 to 10.0, particularly preferably 8 to 9, is preferred.

In addition, the reaction mixture may comprise small amounts of customary additives such as alkali metal sulfites, for example sodium metabisulfite and sodium sulfite, alkali metal formates, for example sodium formate, alkali metal citrates, for example sodium citrate, phosphates, polyphosphates, urea, dicyandiamide or cyanamide. They can be added as pure individual compounds or as a mixture with one another, without solvent or as an aqueous solution, before, during or after the condensation reaction.

Other modifiers are amines and aminoalcohols, such as diethylamine, ethanolamine, diethanolamine or 2-diethylaminoethanol.

Examples of suitable fillers include fibrous or pulverulent inorganic reinforcing agents or fillers, such as glass fibers, metal powders, metal salts, or silicates, for example kaolin, talc, barytes, quartz or chalk, and also pigments and dyes. The emulsifiers used are generally customary nonionic, anionic or cationic organic compounds having long-chain alkyl groups.

The polycondensation can be carried out batchwise or continuously, for example in an extruder (cf. EP-A-355760), in ｃA conventional manner.

The fibers are generally produced by: the melamine resins of the invention are generally spun in a conventional manner, for example at room temperature in a rotary spinning apparatus after addition of a hardener, usually an acid such as formic acid, sulfuric acid or ammonium chloride, and subsequently the curing of the crude fibers is completed in a heated atmosphere, spinning in a heated atmosphere while evaporating off the water used as solvent and curing the concentrate. Such a process is described in detail in DE-A-2364091.

If desired, the melamine resin fibres may contain up to 25% by weight, preferably up to 10% by weight, of conventional fillers added to them, in particular those based on silicates, such as mica, dyes, pigments, metal powders and matting agents.

Other class 1 fibers include: meta-aromatic polyamides such as poly (m-phenylene isophthalamide), for example those sold under the trade name NOMEX by e.i. du Pont de Nemours and co, those sold under the trade name TEIJINCONEX by Teijin Limited, and those sold under the trade name fennelene by Russian State complete; para-aramids such as poly (p-phenylene terephthalamide), for example those sold under the trade name KEVLAR by e.i. dupont de Nemours and co, poly (diphenyl ether para-aramids), for example those sold under the trade name techinra by Teijin Limited, and those sold under the trade name TWARON by Acordis, and FENYLENE ST (Russian StateComplex); polybenzimidazoles such as those sold under the trade name PBI by Hoechst Celanese AcetateLLC; polyimides, such as those sold under the trade name P-84 by Inspec Fibers and those sold under the trade name KAPTON by E.I. Du Pont de Nemours and Co; polyamideimides such as those sold under the tradename KERMEL by Rhone-Poulenc; partially oxidized polyacrylonitriles such as those sold under the trade name FORTAFIL OPF by FORTAFIL Fibers inc, AVOX by Textron inc, PYRON by Zoltek corp, PANOX by SGL Technik, throx by american Fibers and Fabrics and PYROMEX by Toho rayon corp; novoloid, such as phenol-formaldehyde novolacs, such as those sold under the tradename KYNOL by Gun Ei Chemical Industry co.; poly (p-Phenylene Benzobisoxazole) (PBO), such as those sold under the trade name ZYLON by Toyobo co; poly (p-Phenylene Benzothiazole) (PBT); polyphenylene Sulfides (PPS) such as those sold under the tradenames RYTON by American Fibers and Fabrics, TORAYPPS by Toray Industries Inc., FORTRON by Kureha Chemical Industry Co., andthose sold under the trade name PROCON by Toyobo co; flame-retardant viscose rayon, such as those sold under the trade name LENZING FR by LENZING a.g. and VISIL by LENZINGOy, those sold in finland; polyether ether ketones (PEEK), such as those sold under the trade name ZYEX by ZYEX ltd; polyketones (PEKs), such as those sold by BASF under the trade name ULTRAPEK; polyetherimides (PEI), such as those sold under the trade name ULTEM by General Electric co; and combinations thereof.

The most preferred category 1 fibers are also those that are white, off-white, transparent or translucent in color, particularly when used directly under white or light colored decorative upholstery and/or mattress ticking fabrics, as any other color in the nonwoven high loft flame barrier can negatively impact the appearance of the composite article. Thus, when considering this case, on an achromatic scale, white paper has a reflectance value of 80% or greater and black has a reflectance value of about 10%, with the preferred white or off-white fiber color falling closer to the 80% reflectance end of the range (e.g., +/-20). Melamine fibers are particularly well suited for use in this aspect of the invention. Melamine fibers also have outstanding barrier properties, exhibiting a thermal resistance of 0.10 Watts/meter-Kelvin, and they also provide an endothermic cooling effect, absorbing 5 Watts of energy per gram of fiber when thermally decomposed between 370 ℃ and 550 ℃.

Further inherently flame retardant fibres suitable for use in the present invention and preferably in combination with the melamine (heat absorbing) fibres described above are cellulosic fibres, such as viscose rayon based fibres having a high silica content, for example built into the fibre, to provide an insulating barrier in the fibre. A suitable fiber having this characteristic is a Silica (SiO) modified with 33% aluminosilicate₂+Al₂O₃) Viscose rayon-based fiber of Finland, ValkeakokskiAnd (4) manufacturing. The fibers are commonly known and have the trade nameA fiber. It is believed that this material thermally decomposes upon exposure to a flame into a lattice structure having openings that provide passages for volatile liquids (e.g., decomposed polyurethane volatile liquids) that may ignite on opposite sides of the lattice structure. Thus, it is further believed that the use of sufficient class 1 fibers, such as melamine fibers, provides for filling the grid structure with char material, such as carbon char produced from melamine fibers.

Class 2: fibers produced (e.g., extruded) from polymers prepared from halogenated monomers produce an oxygen-depleted gas that helps prevent spontaneous ignition of volatile decomposition vapors of materials below or adjacent thereto, such as polyurethanes, helps to extend the life of class 1 materials (mixed or non-mixed) when subjected to an open flame, and also helps to self-extinguish existing "surface" flames. These fiber types include:

chlorine polymer fibers such as those comprising polyvinyl chloride or polyvinylidene homopolymers and copolymers, for example those sold under the tradenames thermovayl L9S & ZCS, fibrvyl L9F, RETRACTYLL9R, ISOVYL MPS by Rhovyl s.a.; PIVIACID, marketed by Thueringische; those sold under the trade name VICLON by Kureha Chemical Industry co; those sold under the trade name tevirron by Teijin ltd; those sold under the trade name envelon by Toyo Chemical co, and VICRON manufactured in korea; those sold by Pittsfield bathing under the trade name SARAN; those sold under the trade name KREHALON by Kureha Chemical Industry co; those sold by fibriscomni, s.a.de c.v. under the trade name OMNI-SARAN; and modacrylic fibers which are vinyl chloride or vinylidene chloride copolymer variants of acrylonitrile fiber, such as those sold under the trade name PROTEX by Kaneka and those sold under the trade name SEF by Solutia; and combinations thereof.

Fluoropolymer fibers such as Polytetrafluoroethylene (PTFE), for example those sold under the tradenames TEFLON TFE by e.i. du Pont de Nemours and co., those sold under the tradename LENZING PTFE by LENZING a.g., those sold under the tradename RASTEX by w.r. GORE and communications, those sold under the tradename GORE-TEX by w.r. GORE and communications, those sold under the tradename PROFILEN by LENZING a.g., and those sold under the tradename TOYOFLON PTFE by Toray Industries inc, poly (ethylene-chlorotrifluoroethylene) (E-CTFE), for example those sold under the tradename HALAR by albayinternational corporation and those sold under the tradename TOYOFLON E-TFE by Toray Industries, polyvinylidene fluoride (PVDF), for example those sold under the tradenames albayron International corporation and those sold under the tradenames TOYOFLON E-TFE, and those sold under the tradenames perfluoropfa PFA, such as perfluoropfa PFA, those sold under the tradenames berne PFA by tora inc, and those sold under the tradenames of toyof. Fluorinated ethylene-propylene (FEP), such as those sold under the trade name TEFLON FEP by e.i. du Pont de nemours and co; and combinations thereof.

Class 3: low melt binder fibers such as:

low-melt bicomponent polyesters, e.g. sold by Kosa

Polypropylene, such as T-151 sold by Fiber Innovation Technology or by american fibers and Yarns co.

Class 3 fiber combinations

Low-melt fibers are generally those fibers having a melting point lower than the melting point or degradation temperature of the other fibers in the blend. Typical "low melt" fibers used in the industry (polyesters and polyolefins) have a melting point of 110 ℃ to 210 ℃. Regular filled polyesters (high crystallinity) melt at about 260 ℃. Most thermal bonding ovens are limited to operating temperatures below 230 ℃ due to fire and conveyor degradation issues.

Class 4: natural fibers such as:

cotton, wool, silk, mohair, cashmere

Class 4 fiber combinations

Class 5: non-flame retardant fibers, such as:

nylons, polyesters, polyolefins, rayon, acrylics, cellulose acetates and polylactides, such as those available from Cargill Dow Polymers

Class 5 fiber combinations

Category 6: halogenated binder resins such as those based on vinyl chloride and ethylene vinyl chloride.

The fiber blend level concentrations (in wt%) in the nonwoven high loft flame barrier were as follows:

class 1: 10-85%, more preferably 20-70% and even more preferably 30-60%.

Class 2: 10-85%, more preferably 20-70% and even more preferably 30-60%.

Class 3: 0-30%, more preferably 5-25% and even more preferably 10-20%.

Class 4: 0-40%, more preferably 5-30% and even more preferably 10-20%.

Class 5: 0-40%, more preferably 5-30% and even more preferably 10-20%.

Category 6: if used, from 0 to 40%, more preferably from 5 to 30% and even more preferably from 10 to 20%.

While the preferred embodiment of the present invention is a thermally bonded nonwoven high loft, the fibers mentioned in categories 1, 2, 4 and 5 and the binder material of category 6 may also be employed to prepare suitable resin bonded high loft flame shields of the present invention. The thermal bonding blend can also be coated (e.g., on one or both sides) with a light sprayed class 6 resin coating to "lock" the surface fibers in place. This prevents the surface fibers from percolating or migrating through the coverstock after undergoing use. The fiber percolation imparts an undesirable hazy appearance to the upholstery cover material.

The oxygen-depleted gas produced by the class 2 fibers is beneficial in combination with the class 1 material. That is, in addition to helping to prevent spontaneous ignition of decomposition products from underlying layers, such as polyurethane foam and the like, and helping to extinguish residual flames emanating from overlying materials, such as clothing cover fabrics, the oxygen-depleting gases from polymers prepared with halogenated monomers also cover and protect the carbon-containing char formed during the decomposition of the inherently flame resistant fibers. In this way, when exposed to air at open flame temperatures, significantly more time is provided before the char disintegrates. This synergistic blending under the present invention is thus able to withstand extended periods of time with minimal shrinkage of the char shield, thereby preventing the flame from "breaking through" the char shield and igniting the material beneath it. For this reason, a combination of a certain number of category 1 and 2 fibers is preferred, for example, over relying only on category 1 fibers (e.g., in combination with a low density, high loft shield in a number in the middle to the higher end of the above range) and without the contribution of category 2 material.

Other component fibers may optionally be included, preferably in relatively low concentrations, such as: natural fibers to improve product economics in end-use applications.

The above percentage ranges for each category refer to the weight percentage of a single layer of material (e.g., a flame barrier formed from a common blend of fibers throughout the thickness, or to one layer of a multi-layer flame barrier, with the other layers also being provided for flame barrier purposes or not). In addition, the above weight percentages may also be considered to apply to the weight percentages of the sum of the individual layers of the multilayer flame barrier. For example, the present invention is intended to include within its scope a multi-layer flame barrier combination having the same or different percentages of class 1 and/or 2 materials in two or more layers thereof (including zero percent of one of class 1 and 2 materials in one layer, the other layers making up the difference). For example, a multi-layer flame barrier may include one layer designed to provide or emphasize a class 1 material, and a second layer designed to provide or emphasize a desired percentage of a class 2 material. While certain combinations of materials, particularly class 1 and 2 materials, may provide highly advantageous flame barrier functions, as will become more apparent below, the present invention provides a high degree of versatility in forming flame barriers, as can be seen from the several embodiments described immediately above, and additional embodiments described hereafter. Also, a single or non-multilayer flame barrier (based, for example, on an input fiber mixture blend "recipe" based on the above possible combination of classes into a computer processor that controls the high loft nonwoven product manufacturing process) having a common blend composition throughout its thickness is preferred for many applications, for example, from the standpoint of reducing manufacturing complexity and cost.

The high loft flame barrier of the present invention may also be used in the manufacture of open flame resistant composite articles while also allowing the continued use of conventional non-flame resistant apparel cover fabrics, conventional non-flame resistant fiber fillers, conventional non-flame resistant polyurethane foams, and the like.

According to another aspect of the invention, by employing additional composite article components such as: conventional non-flame resistant garment cover fabrics, conventional non-flame resistant fibrous fillers, and conventional non-flame resistant polyurethane foams incorporate flame barriers, the high loft flame barriers described herein can be used in the manufacture of open flame resistant end use composite articles, and such additional composite article components have been used, for example, in the manufacture of upholstered furniture, mattresses, pillows, bedsheets, duvets, mattress pads, automobile seating, transportation seating, and aircraft seating. Because laminating resins tend to stiffen the "feel" of the decorative fabric, the high loft flame barrier of the present invention can be used without laminating to the garment shell fabric, which is an advantage over some forms of currently available flame barriers. The high loft flame barrier product may also be used as a substitute for conventional non-FR high loft batting. Such high loft shields may also be advantageously laminated to the polyurethane foam layer, such as by adhesive coating, as is currently practiced in most upholstered furniture industries. This reduces the number of raw material units that must be handled in the furniture manufacturing process. Thus, the present invention also provides for the continued use of conventional non-flame retardant materials in, for example, the formation of upholstered furniture and mattresses, without altering or interrupting conventional composite article manufacturing processes, except that it is possible to make the process simpler by reducing one or more steps in the existing processes, such as the step of removing the FR material applied to the article. With the flexibility in sizing in the high loft flame barrier described above, a similarly sized high loft flame barrier substitute (alone or as a laminate with some other material, such as smaller amounts of existing conventional materials) may also be used in place of an existing component (such as a fiber batting) without interrupting the overall composite manufacturing technique.

The composite article produced, and thus the flame barrier itself and each additional component of the composite article, may advantageously be free of any fire resistant coatings and chemicals and still pass the stringent open flame test described above.

Detailed description of the preferred embodiments of the invention

The present invention is directed to providing a nonwoven high loft flame barrier, and in particular a flame barrier that, when tested in composite articles using composite testing methods, such as california test bulletin 129(Cal TB129) for mattresses and california test bulletin 133(Cal TB133) for upholstered furniture, allows for continued use of conventional garment shell fabrics, fiber fillers, polyurethane foams, and the like, while still passing these stringent large open flame tests. It is understood by those skilled in the art that the flame barrier of the present invention comprised of the fiber blend can be made to pass the less stringent small open flame test even at an overall lower basis weight.

The term "high loft" is used in a generic sense to refer to lofty, relatively low density nonwoven fibrous structures. These materials typically have a larger volume of air than the fibers. The term is also used to describe nonwoven materials that are produced with the aim of building bulk or thickness without adding weight. High loft, as used herein, also refers to a product that is not compacted or purposely compressed during the manufacturing process. Representative examples of basis weight, caliper and other blend and forming characteristics of the high loft materials of the present invention are further provided below.

The nonwoven high loft flame barrier of the present invention is particularly well suited for use as a component material in the manufacture of furniture, bedding articles, bed coverings and the like, such that the coating of an added protective layer, such as an FR material, on, for example, an exterior decorative covering, need not be used to make the composite article resistant to open flames. The present invention is therefore designed to be incorporated into the manufacturing process of many composite articles without interrupting their current process, and therefore provides an uninterrupted manufacturing alternative to: materials or articles currently used by manufacturers such as padding, cushioning, layers of stitching, etc.

Composite articles made with the nonwoven high loft flame barrier have the appearance, feel, and surface characteristics of the same products made without the inventive subject matter while providing flame barrier properties. For example, one standard test for measuring open flame resistance of a mattress is the california test bulletin 129. According to this test, a full size mattress was exposed to a 3 minute flame burner, held level from 1 inch from the bottom/center on the side edges of the mattress. The mattress of the present invention may employ the above-described non-woven high loft flame barrier, for example, by sewing the barrier directly under the mattress ticking fabric and over a layer of standard polyester high loft batting or standard non-FR polyurethane foam. When such a shield is incorporated, additional severe open flame tests that the composite articles of the present invention or composite models representing such articles are intended to pass include: california test bulletin 133, recommended Customer Product Safety Commission (CPSC) flammability test, composite british standard 5852-Crib5, british standard 7176, and british standard 7177.

The forming process of the present invention preferably includes a chemical, thermal or non-adhesive forming process of the nonwoven high loft flame barrier. These techniques are preferred over techniques such as mechanical bonding techniques. Mechanical bonding techniques rely on entanglement of the fibers to add sufficient strength to resist damage caused by normal processing and intended use. Conventional mechanical bonding techniques used are typically based on hydroentanglement, needle punching and/or stitch bonding, or any other technique that uses mechanical measures to physically entangle the fibers after carding. The use of mechanical bonding techniques in the present invention is less preferred than chemical, thermal or non-bonding forming techniques, since the mechanical means of bonding significantly reduces the loft or thickness of the material, since the physical orientation of the fibers relative to each other is adjusted, resulting in a reduction in loft or loft for a given weight, and a corresponding increase in density.

The non-mechanical high loft bond used in the present invention helps provide barrier properties that enable the present invention to achieve the high open flame resistance described above. While thermal and/or spray resin bonding is preferred to maintain the desired high loft properties, a combination of mechanical, thermal and/or chemical bonding techniques may be relied upon, such as the above-described surface resin spray onto the thermally bonded nonwoven shield. As another example of a combination of techniques that maintain the desired high loft properties, a mechanical bonding apparatus may be used in combination with other non-mechanical bonding techniques to provide various finished product properties. For example, mechanical techniques may be used to compact or densify one side (and the top or bottom) of the material while the other side remains fluffy. This produces various air flow properties and produces differences in hand or surface feel. It is therefore considered that the bulk values provided herein represent values for non-mechanically bonded portions or regions of high loft material. If mechanical bonding is used in combination with the non-mechanical bonding techniques described above, it is preferred to use only a small percentage (e.g., less than 10%) such as to affect only the overall portion (volume or area) of the flame barrier in fewer situations. Likewise, if mechanical bonding techniques are employed over a larger material area, it is preferred that the initial bulk and density values be substantially maintained by a lesser degree of bonding by mechanical means (e.g., the bulk or caliper values obtained are within 20% of the values where no mechanical bonding supplementation of the finished product is achieved at all).

In chemical bonding, a resin or adhesive, typically in the form of a latex, is sprayed onto a carded web and then dried and/or cured, thereby bonding the fibers together in their existing orientation. The sprayed substance acts as a "glue" that holds the fibers together and creates a bond point at the intersection or point where two or more fibers meet. Saturated bonding is similar except that the web is immersed in a resin bath without spray application of resin. Given the flammable nature of most chemical binders, the impregnation method is less preferred. FR additives can be added to the resin, but these are expensive and also add to the cost of the process, and as noted above, do not need to be used in the preferred arrangement of the present invention. Chemical adhesive methods have environmental problems that are also responsible for the fact that saturation methods are not the preferred bonding method for many applications.

The thermal bonding uses binder fibers. Binder fibers are typically composed of a polymer having a melting point lower than the melting point of the "filler" fibers or other fibers in the blend. The binder fibers are then melted in the presence of heat in a subsequent processing step. The binder, in molten form in the presence of heat, flows to the intersecting portions of the fibers and re-hardens and forms bonds upon cooling. These bonds allow the fibers to remain in their existing orientation. The binder fibers may be solid, single polymer fibers having a melting point significantly lower than the filler fibers in the blend. The binder may also be a sheath/core fiber, with the sheath component being a low melting polymer and the core being a relatively higher melting polymer.

These thermal/adhesive bonding techniques produce finished materials with significantly higher loft or caliper for the same basis weight than mechanical bonding measures. The thickness and loftiness of the product in the preferred use of the invention is beneficial in that it provides good cushioning properties, the aesthetics of the finished quilt panel, and ease of access for general use in a proposed article (e.g., no change in the article in which the shield is used to house the shield). The invention can also be produced and incorporated into articles without any bonding. Non-bonded nonwovens are commonly referred to in the art as "textiles (softgoods)". Even without bonding, the material will remain in a high loft configuration. Textiles are used, for example, in certain composite articles such as furniture and are sufficient to maintain their assembly through natural entanglement (i.e., non-mechanical entanglement) that occurs in high loft manufacturing web formation processes, i.e., carding, garnetting, air laying. In some cases, a thin strip of laminate material or other transport/processing facilitating tool is added to one surface of the textile body.

The high loft nonwoven shield material of the present invention can be made in a variety of ways, some of which are described in the following documents: Kirk-Othmer "encyclopedia of chemical technology" 3 rd edition, volume 16, pages 72-124, "nonwoven textile fabrics", which is incorporated herein by reference. A preferred manufacturing process for forming the shield of the present invention includes transferring the fibrous material supplied from the pressed bale through a feed device, such as a feed conveyor or a roller, to an opener designed to separate the fibrous material, thus initiating fiber opening and separation, transferring the opened fibrous material to a continuous or intermittent weighing device designed to weigh the opened fibrous material, and blending a weighed amount of the opened fibrous material in a blender to achieve a desired amount of a uniform blend of opened fibrous material. The manufacturing process further includes conveying the opened, weighed, and blended fiber material to a nonwoven forming apparatus, such as a carding apparatus, to form a web of nonwoven material. Preferably the method comprises cross-laying or layering the webs in a cross-laying apparatus or the like until a desired thickness of the nonwoven high loft material of predetermined basis weight is obtained.

Each of the above slave phases is preferably controlled and regulated by use of a central processor in communication with the respective "devices in the overall system". This allows, for example, the operator to input a desired blend formulation having the desired weight percent amounts of the desired class of materials to be used, and to control the basis weight of the blended fibers and the thickness of the desired nonwoven high loft flame barrier layer (e.g., the number of cross-plied webs). Opening and blending of the fibers is preferably performed using high quality fiber openers and blenders designed to produce a uniform blend of the fibers accurately. Suitable opening and blending equipment includes bale openers and fine openers manufactured by Fiber Controls, Gastonia, north carolina, and blended Fiber stock chutes manufactured by DiloGroup, Bremen, germany. Opening is preferably performed by using multiple opening stages, with each subsequent stage representing finer opening and more fiber separation to help achieve a more uniform and accurate final blend. After multiple opening stages, all opened fiber components used in the desired final blend are preferably weighed prior to blending to ensure an accurate percentage of the blend. This blending step may be accomplished without weighing, but poor blending may negatively impact the final flame retardant properties of the flame barrier of the present invention by allowing for relatively low concentrations of key components in the material region.

Blending involves mixing the weighed fibers by layering the weighed components and feeding through a blend roll beater (which may use a pin or saw tooth wire configuration) that rotates at a high speed ratio relative to the weighed component speed and is conveyed into a pipe-fed or stock Feed hopper, such as the "Direct Feed" brand hopper sold by Dilogroup, Bremen, Germany. Further blending may be accomplished by processing the pre-blended components through a stock blending mixing chamber such as a type 99 stock chamber sold by Fiber Controls, inc.

The opened and blended fibers are then processed through a high quality nonwoven carding unit (such as a high loft nonwoven carding unit of the type 1866 sold by Dilo Group, Bremen, germany), and the resulting web is cross-plied or layered (such as through a CL-4000 series cross-plier sold by Autefa, germany) to form a high loft web. In a typical carding process, a series of wire-winding rollers are employed that rotate at various speeds (depending on the application and the product to be carded), which can be controlled by a control processor. Most carding units consist of a carding section with a large main roll and smaller diameter rolls around the main roll arc. The second large main roller is provided with a small cylinder between the main roller of the briseur and itself. A series of smaller rollers are disposed around the second main roller. The carded web is removed from the carding apparatus in two small rolls, which are located on top of each other in a vertical arrangement. A variety of configurations of the carding apparatus are available. The speed of the rolls is generally adjustable in a given carding machine to allow a wide range of fibers and deniers to be processed. In carding machines, the fibres are carded or combed by moving the toothed wire against the fibre mat fed through the machine. This same process is accomplished by garnetting and other various web forming machines such as air laid webs. The web exiting the carding unit or web former may be used directly or may be cross-plied vertically or horizontally to build product loft or thickness and weight. The cross-plied or stacked continuous carded web allows the nonwoven to be formed to various desired thicknesses and weights. In one embodiment of the invention, the web incorporating the bonding fibers is carried through a forced air, gas fired continuous oven at a temperature of up to 500 ° F so that bonding of the web occurs. The bonding temperature depends on the adhesive component in the blend. The material is then subjected to final processing such as rolling and slitting the material on a roll to the width of each application. Depending on the particular application, the material may also be cut into panel-sized pieces.

The preferred "equipment set-up" described above enables the production of a weight of 40g/m²(and a thickness range of 5mm-10 mm) to 1800g/m²Or higher (with caliper or bulk ranges of 150mm to 250mm and higher).

The basis weight of the high loft nonwoven material of the present invention is preferably 75 to 600g/m²More preferably 150-450g/m²And even more preferably 300-375g/m for many intended uses². The thickness of the high loft nonwoven material of the present invention is also preferably 6mm to 75mm, with a thickness range of 7 to 51mm being well suited for many uses of the present invention. Since at the high end of the above basis weight range there is too low a basis weight for a given thickness, it may be the case thatLower degradation shielding, it is desirable for some applications to use a lower end basis weight value in conjunction with a lower end thickness range, which is generally not considered for higher end basis weights. Therefore, 75g/m²To a basis weight level (with a preferred bulk or thickness range of 6mm-13 mm) of 450g/m²The basis weight level (versus the preferred bulk or thickness range of 25mm to 51 mm) represents some preferred ranges for the present application. A further preferred combination, well suited for many of the intended uses of the present application, includes a flame barrier for bedding related products, including 300g/m²(with preferred thickness or bulk range of 20mm-35 mm) -375g/m²(with a preferred thickness or loft range of 25mm-50 mm) weight/thickness.

The "high loft" form described above is the preferred form of the flame barrier of the present invention as it provides, among other qualities, increased thermal insulation qualities. This insulating effect helps prevent spontaneous ignition of components such as polyurethane foam, although the flame does not actually damage the shield to expose the foam. Higher or lower bulk, weight and density are possible, but the above ranges are well suited for preferred use as follows: providing "seamless" open flame barrier assemblies in articles such as those described above, while avoiding, for example, degrading aesthetics, feel, comfort, and other desired qualities in such articles and without introducing undesirable manufacturing complexity and costs. Also, too low a basis weight for too high a thickness may result in there being areas in the shield through which flames may pass. The values stated above are relative to the preassembly configured with the composite article. The post-assembly thickness and hence density values may vary depending on the assembly technique, but thickness losses of no more than 50% of the original height are generally achieved. As an example, a 10% -25% loft loss may be achieved in quilted panels for mattress construction. This typically occurs as a result of: the fibers are quilted and sewn into ticking and are kept at a lower loft due to the mattress manufacturing process. The thickness and basis weight values of the pre-assembly configuration are established to contribute to the level of flame shielding required to function with the final assembly in the desired composite article.

The following non-limiting "composite article" test examples I and II are presented to demonstrate the effectiveness of mattresses made with the flame barrier of the present invention through the severe open flame test (TB Cal 129), while the comparative composite article examples provide comparative test samples. Following these examples is additional "composite article" test example III, characterized by a combined mixture of different class 1 fiber types. Each of these test examples was conducted only on the mattress itself (i.e., no substrate or spring mattress).

Composite article example I

A commercial dual mattress constructed using the following materials:

a mattress quilt panel sewn with non-FR quilting stitches, consisting of:

commercial mattress cover fabric class A from Blumenhal Mills Inc. (aristoctra "22" T-VBS 701)

-a layer 1 under the quilt cover consisting of:

-a nonwoven thermally bonded high loft flame barrier consisting of a fiber blend of:

-55% melamine/30% polyester (100% PET (polyethylene terephthalate), melting temperature of 260 ℃)/15% binder fiber "PET/PET" binder fiber 50%/50% sheath/core, wherein the sheath has a melting temperature of 100 ℃ and the core has a melting temperature of 260 ℃.

-153 g/m in the uncompressed state²And an average batt basis weight range of 25 mm.

-a layer 2 under the quilt wadding consisting of:

-a nonwoven thermally bonded high loft flame barrier comprised of a blend of fibers, the blend comprising:

20% Melamine/60% modacrylic fiber (PROTEX-M available from Kaneka, Japan)/20% binder fiber

-229 g/m in the uncompressed state²And an average batt basis weight range of 25 mm.

-a 3 rd layer under the quilt cover consisting of:

nonwoven thermal bonded high loft 100% "brushed" polyester batting available from Western Nonwovens, inc

-in the uncompressed state has 305g/m²And an average batt basis weight of 25 mm.

-a 4 th layer under the quilt wadding consisting of:

1 "layer of non-flame-retardant (FR) polyurethane foam (R17S type) from Carpenter Co

Layer 5 of 1 opsy nonwoven spunbond polyester scrim from Hanes Converting co.

A mattress edge panel sewn with non-FR quilting stitches, comprising:

-a layer 1 under the quilt cover consisting of:

55% melamine/30% polyester/15% binder fiber

-153 g/m in the uncompressed state²And an average batt basis weight of 25 mm.

-a layer 2 under the quilt wadding consisting of:

20% Melamine/60% modacrylic fiber/20% binder fiber

-229 g/m in the uncompressed state²And an average batt basis weight of 25 mm.

Layer 3 of a 0.5 opsy nonwoven spunbond polyester scrim from Hanes Converting co.

The mattress is composed of the following materials:

layer 1 over the innerspring of a 100% polyester netting

Layer 2 over the innerspring (type L32S) of 0.375 "non-FR polyurethane foam from Carpenter Co

Layer 3 over the innerspring (type S17S) of 1.75 "non-FR polyurethane foam from Carpenter Co

The mattress quilt panel was sewn to the mattress edge panel with a 1.25 "wide Firegard mattress narrow fabric (style 4368). The Firegard line and all mattress corners are protected by standard loose cotton padding.

The dual mattress of the above construction was tested on Omega Point Laboratories (Elmendorf, TX) according to the california test bulletin 129. All flames stopped after 5 minutes 26 seconds on the mattress and all smoldering of the mattress stopped after 6 minutes 0 seconds. The peak rate of heat release was 19.69KW (maximum allowable rate of heat release was 100KW), the total heat release was 2.53MJ (maximum allowable value in the first 10 minutes was 25MJ) and the weight loss in the first 10 minutes was 0.5 pounds (maximum allowable value in the first 10 minutes was 3 pounds). This test was deemed to pass CAL TB129 significantly.

Composite article example II

A commercial dual mattress constructed using the following materials:

a mattress quilt panel sewn with non-FR quilting stitches, consisting of:

-a layer 1 under the quilt cover consisting of:

38% melamine/47% modacrylic/20% binder fiber

-in the uncompressed state has a density of 381g/m²And an average batt basis weight of 32 mm.

-a layer 2 under the quilt wadding consisting of:

Layer 3 of 1 opsy nonwoven spunbond polyester scrim from Hanes Converting co.

A mattress edge panel sewn with non-FR quilting stitches, the panel consisting of:

-a layer 1 under the quilt cover consisting of:

38% melamine/47% modacrylic/20% binder fiber

Layer 2 of 0.5 opsy nonwoven spunbond polyester scrim from Hanes Converting co.

The mattress is composed of the following materials:

layer 1 of cotton "plush pad" over the innerspring

-0.375 "layer 2 of non FR polyurethane foam over the innerspring (type L32S)

The mattress quilt panel was sewn to the mattress edge panel from a 1.25 "standard polyester mattress sheer fabric and a Tex-45 Kevlar thread.

The dual mattress of the above construction was tested on Omega Point Laboratories (Elmendorf, TX) according to the california test bulletin 129. All flames stopped on the mattress after 6 minutes 10 seconds. The peak rate of heat release was 27.36KW (maximum allowable rate of heat release was 100KW), the total heat release after 10 minutes was 5.37MJ (maximum allowable value in the first 10 minutes was 25MJ) and the weight loss in the first 10 minutes was 0.0 pounds (maximum allowable value in the first 10 minutes was 3 pounds). This test was deemed to pass CAL TB129 significantly.

Comparative composite article examples

A commercial dual mattress constructed using the following materials:

a mattress quilt panel sewn with non-FR quilting stitches, consisting of:

-a layer 1 under the quilt cover consisting of:

55% melamine/30% polyester/15% binder fiber

-in the uncompressed state has 305g/m²And an average batt basis weight range of 25 mm.

-a layer 2 under the quilt wadding consisting of:

nonwoven thermal bonded high loft 100% polyester batting available from Western nowvens, inc

-a 3 rd layer under the quilt cover consisting of:

Layer 4 of 1 opsy nonwoven spunbond polyester scrim from Hanes Converting co.

A mattress edge panel sewn with non-FR quilting stitches, comprising:

-a layer 1 under the quilt cover consisting of:

55% melamine/30% polyester/15% binder fiber

Layer 2 of 0.5 opsy nonwoven spunbond polyester scrim from Hanes Converting co.

The mattress is composed of the following materials:

layer 1 over the innerspring of a 100% polyester netting

The dual mattress of the above construction was tested on Omega Point Laboratories (Elmendorf, TX) according to the california test bulletin 129. The mattress failed the maximum heat release rate standard test at 5 minutes 48 seconds and terminated at 8 minutes 6 seconds.

A maximum peak rate of heat release of 379.46KW was obtained at 8 minutes and 6 seconds (maximum allowable rate of heat release was 100KW), the total heat release during the first 8 minutes and 6 seconds was 44.76MJ (maximum allowable value over the first 10 minutes was 25MJ) and the weight loss in the first 8 minutes and 6 seconds was 2.2 pounds (maximum allowable value over the first 10 minutes was 3 pounds). This test was not considered to pass the stringent CAL TB129 test due to the maximum peak rate of heat release exceeding 100KW and exceeding the total heat release rate.

In the present inventionIn an alternative embodiment, the blend is characterized by a mixture of different class 1 inherently flame resistant fibers, such as a blend of melamine fibers (an example of an endothermic thermally degraded fiber) and inherently flame resistant cellulosic fibers (an example of an exothermic degraded fiber). By way of example, an alternative embodiment of the invention is preferably characterized by a significant amount (e.g., greater than 20%) of cellulosic fibers, such as tacky rayon-based fibers with a thermal insulation layer of silica, such as fibers comprising 33% aluminosilicate modified silica, SiO₂+Al₂O₃The tacky rayon-based fiber of (1). Suitable variants of this type of fiber in raw form are prepared by the method of Valkeakoske, FinlandOy. The fiber is commonly referred to by its trade nameA fiber. It is preferable thatThe fibers are Visil 33 AP obtained at a decitex value of 1.7-8.0, Visil 33 AP (decitex of 5.0) being a preferred type which is within the stated range and is also considered suitable for use in accordance with the present invention.

In one embodiment of the invention, the blend comprises a class 1 combination of fibers such as melamine fibers (e.g., 10-50% melamine fibers) and a significant amount (e.g., 10-50%) of viscose-based rayon fibers. Preferably the melamine and viscose based rayon percentage values are from ± 15% to 25% of each other (i.e. the endothermic melamine fibers are more by weight with respect to the viscose based rayon (e.g. exothermic fibers) and vice versa or are equal by weight). As an example of a suitable blend of a class 1 conjugate, blend with 30% (+ -10)Melamine fibers together, in an amount of 30% (+ -10) providing a fiber containing the above aluminosilicate modified silicaFibers and either a class 1 conjugate is blended or otherwise utilized with a class 2 halogenated monomer fiber, such as the modacrylic fibers referred to in the present examples in this application. For example, for class 2 materials, an amount of 10-40% (e.g., 20%) is well suited for the above-described mixture combinations of class 1. The above mixture further preferably includes a 4-denier thermal adhesive in an amount such as 20% (± 5).

Pilot lab scale testing using CAL TB129 burners revealed that this new blend was effective against burn-through. This introduces the potential to use lighter weights for the same relative performance criteria, thus providing the potential to reduce the overall cost of manufacturing the article. Composite article embodiments employing the above class 1 blend features are provided below with respect to mattresses (without a substrate) tested according to california test publication 129.

Composite article example III

A commercial dual mattress constructed using the following materials:

a mattress quilt panel sewn with non-FR quilting stitches, the panel consisting of:

polyester/cotton bedding cover fabric for residential use

-a layer 1 under the quilt cover consisting of:

25% Melamine/33% Visil/20% modacrylic fiber/22% binder fiber

-153 g/m in the uncompressed state²And an average batt basis weight of 15 mm.

-a layer 2 under the quilt wadding consisting of:

1' layer of non-flame-retardant (FR) polyurethane foam

-layer 3 of 1 opsy nonwoven spunbond polyester scrim.

polyester/cotton bedding cover fabric for residential use

-a layer 1 under the quilt cover consisting of:

25% Melamine/33% Visil/20% modacrylic fiber/22% binder fiber

-153 g/m in the uncompressed state²And an average batt basis weight of 15 mm.

-layer 2 of 0.5 opsy nonwoven spunbond polyester scrim.

The mattress is composed of the following materials:

100% compacted polyester high loft layer 1 above the innerspring

-1 "layer 2 of non-FR polyurethane foam over innerspring

The mattress quilt panel was sewn to the mattress edge panel with a decorative polyester mattress sheer fabric and Kevlar thread.

The dual mattress of the above construction was tested on Omega Point Laboratories (Elmendorf, TX) according to california test bulletin 129. All flames stopped on the mattress after 53 minutes 06 seconds. The peak rate of heat release was 36.7KW (maximum allowable rate of heat release was 100KW), the total heat release after 10 minutes was 7.8MJ (maximum allowable value in the first 10 minutes was 25MJ) and the weight loss in the first 10 minutes was 0.7 pounds (maximum allowable value in the first 10 minutes was 3 pounds). This test was deemed to pass CAL TB129 significantly.

While the invention has been described in detail with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made, and equivalents employed, without departing from the scope of the appended claims.

Claims

1. A nonwoven high loft flame barrier comprising a blend of:

a)20 to 70 weight percent of inherently flame resistant fibers selected from the group consisting of melamine, meta-aramid, para-aramid, polybenzimidazole, polyimide, polyamideimide, partially oxidized polyacrylonitrile, novoloid, poly (p-phenylene benzobisoxazole), poly (p-phenylene benzothizole), polyphenylene sulfide, flame retardant viscose rayon, polyetheretherketone, polyketone, polyetherimide and combinations thereof;

b)20-70 wt% modacrylic fiber;

c) up to 30 wt% low melt binder fiber; and is

The fibers are blended and processed by non-mechanical bonding such that the resulting fibers have a volume of air greater than the volume of the fibers and a bulk density of from 5 to 50kg/m³The blend of (1).

2. The flame barrier of claim 1, wherein the flame barrier is used in mattresses, upholstered furniture, fiber-filled bed coverings, transportation vehicle seating.

3. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise melamine fibers in admixture with: at least one additional type of inherently flame resistant fiber having different heat resistant characteristics.

4. The flame barrier of claim 1, wherein said flame barrier is formed by a thermal bonding process.

5. The flame barrier of claim 1, wherein the flame barrier is comprised of a plurality of flame barrier layers.

6. The flame barrier of claim 5 wherein a first of said layers comprises said inherently flame retardant fibers and modacrylic fibers and a second of said layers comprises inherently flame retardant fibers and is free of modacrylic fibers.

7. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise endothermic thermally decomposing inherently flame retardant fibers.

8. The flame barrier of claim 7 wherein the inherently flame retardant fibers further comprise exothermic thermally decomposing inherently flame retardant fibers.

9. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a mixture of melamine fibers and flame retardant viscose rayon fibers.

10. The flame barrier of claim 9 wherein the weight percent of each of said inherently flame retardant fibers is 30 ± 15% relative to the total flame barrier weight.

11. The flame barrier of claim 1 further comprising non-flame retardant fibers and wherein the non-flame retardant fibers are present in an amount of 1 to 60 weight percent.

12. The flame barrier of claim 11 wherein said non-flame retardant fibers are non-natural fibers selected from the group consisting of: nylon, polyester, polyolefin, acrylic, cellulose, acetate, polylactide, and combinations thereof, and is present in an amount of 1-30% by weight of the flame barrier.

13. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise flame retardant viscose rayon fibers.

14. The flame barrier of claim 1 wherein a majority of the inherently flame retardant fibers are melamine derived.

15. The flame barrier of claim 1, further comprising natural fibers.

16. The flame barrier of claim 15 wherein said natural fibers are selected from the group consisting of cotton, wool, silk, mohair, cashmere, and combinations thereof.

17. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

18. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of meta-aramid fibers and flame retardant viscose rayon fibers.

19. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of meta-aramid fibers and flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

20. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of para-aramid fibers and flame retardant viscose rayon fibers.

21. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of para-aramid fibers and flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

22. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of polyamideimide fibers and flame retardant viscose rayon fibers.

23. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of polyamideimide fibers and flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

24. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of polyphenylene sulfide fibers and flame retardant viscose rayon fibers.

25. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of polyphenylene sulfide fibers and flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

26. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of novoloid fibers and flame retardant viscose rayon fibers.

27. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of novoloid fibers and flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

28. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of polyimide fibers and flame retardant viscose rayon fibers.

29. The flame barrier of claim 1 wherein said inherently flame retardant fibers comprise a combination of polyimide fibers and flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

30. The flame barrier of claim 1, wherein said inherently flame retardant fibers comprise a combination of polyetherimide fibers and flame retardant viscose rayon fibers.

31. The flame barrier of claim 1, wherein said inherently flame retardant fibers comprise a combination of polyetherimide fibers and flame retardant viscose rayon fibers comprising silica or aluminosilicate modified silica.

32. The flame barrier of claim 1 further comprising up to 40% non-flame retardant fibers.

33. The flame barrier of claim 1 wherein the bulk density is 6 to 21kg/m³。

34. A nonwoven high loft flame barrier comprising a blend of:

b)20-70 wt% modacrylic fiber;

c) a halogenated binder resin; and is

35. The flame barrier of claim 34, wherein the flame barrier is used in mattresses, upholstered furniture, fiber-filled bed coverings, transportation vehicle seating.

36. The flame barrier of claim 34, further comprising 1-60 wt% non-flame retardant fibers.

37. The flame barrier of claim 36, wherein the non-flame retardant fibers are non-natural fibers selected from the group consisting of: nylon, polyester, polyolefin, acrylic, cellulose acetate, polylactide, and combinations thereof and comprise 1-30 wt% of the flame barrier.

38. A nonwoven high loft flame barrier comprising a blend of:

b)20-70 wt% modacrylic fiber;

c) up to 40 wt% natural fibers; and

d) up to 40 wt% non-flame retardant polymer fibers; and is

The inherent flame-retardant fiber and the modified polyacrylonitrile fiber are blended to obtain the fiber with the volume of air larger than that of the fiber and the bulk density of 5-50kg/m³The blend of (1).

39. The flame barrier of claim 38, wherein the flame barrier is used in mattresses, upholstered furniture, fiber-filled bed coverings, transportation vehicle seating.

40. The flame barrier of claim 38 wherein said inherently flame retardant fibers comprise 30 to 60 weight percent of said fiber blend and the modified polyacrylonitrile fibers provide 30 to 60 weight percent of the fiber blend.

41. The flame barrier of claim 38, wherein it further comprises low melt binder fibers comprising up to 30 wt% of the fiber blend.

42. The flame barrier of claim 38, wherein said inherently flame retardant fibers comprise a mixture of exothermic and endothermic inherently flame retardant fibers.

43. The flame barrier of claim 38 wherein said blend further comprises cellulosic fibers.

44. The flame barrier of claim 38 wherein said blend further comprises viscose rayon fiber with silica.

45. The flame barrier of claim 44 wherein said viscose rayon fiber comprises aluminosilicate modified silica.

46. A product decorated or manufactured with the nonwoven high loft flame barrier of claim 1.

47. The product of claim 46, wherein the product is a composite article comprising a flame barrier and at least one other article component.

48. The product of claim 47, wherein the product is capable of passing at least one of the following stringent open flame test protocols: california test bulletin 133, california test bulletin 129, and british standard 5852 using crib5 flame sources.

49. The product of claim 47 wherein the at least one other article component comprises a foam layer.

50. The product of claim 47, wherein the product is a mattress component.

51. The product of claim 47 wherein the at least one other article component is in contact with the flame barrier and is less flame resistant or flame retardant than the flame barrier.

52. The product of claim 47 wherein the other article comprises a fabric covering.

53. The product of claim 47, wherein the product is free of a refractory coating in use.

54. The product of claim 46, wherein the product is capable of passing at least one of the following stringent open flame test protocols: california test bulletin 133, california test bulletin 129, and british standard 5852 using crib5 flame sources.

55. The product of claim 46, wherein the flame barrier is multilayered.

56. The product of claim 55 wherein both of the layers comprise different weight percentages of inherently flame resistant fibers and modacrylic fibers.

57. The product of claim 46, wherein the product comprises an outer covering fabric layer that is free of a fire resistant coating and is disposed in contact with said flame barrier.