Field

[0001 ] The invention relates to a process for treatment of fabrics and in particular a process for treatment of fabrics including multifiber yarn which improves the resistance of the fabric to abrasion induced defects such as fuzzing, pilling and fiber loss. The invention further relates to a modified multifiber yarn fabric having improved resistance to abrasion damage.

Background

[0002] The surface appearance of fabrics is very important to consumers.

Resistance to abrasion damage such as fuzzing, pilling, snags, thinning and hole formation is therefore of primary importance to yarn and fabric manufacturers as well as retailers of fabrics and clothing. There is also a growing awareness of the potential for release of synthetic fibers into the waterways after laundering of abrasion damaged fabric.

[0003] Damage caused by abrasion such as the fabric rubbing against itself, other fabric such as during laundering or even with skin during use, can cause fiber migration from the yarn to the fabric surface producing fuzzing and pilling which refers to the formation of visible bunches or balls of tangled fibers associated with the fabric surface.

[0004] Most fabrics exhibit some degree of fuzzing and pilling with wear but the problem is most apparent in fabrics constructed from multifiber yarn and in particular mutifiber yarns which contain synthetic fibers such as polyester and polyamide. Yarn spun from staple fibers and blends of staple fibers and synthetic filaments exhibit the most significant problem due to the tendency of staple fibers and damaged synthetic fibers to produce pills attached more firmly to the fabric by relatively strong synthetic fibers.

[0005] Furthermore abrasion damage such as pilling becomes more pronounced when constituent fibers of a multifiber yarn have a finer denier such as 1 .5dpf or finer. [0006] The problem of abrasion damage has been addressed primarily through modification of the process of yarn manufacture or through modifying the structure of yarn or fabrics. Process steps such as the use of heat setting or singeing of fibers are used to improve resistance to abrasion induced damage. Modification of the yarn structural features such as fiber blend composition, fiber denier, the twist factor of yarn comprising staple fibers or the yarn count or combination of these factors can be used to reduce pilling.

[0007] Topical treatment compositions and film forming emulsionbinders such as polyurethanes, carboxylate latex, styrene butadiene latex, have been used as fabric coatings and generally cure to form a cross-linked matrix on yarn to encase the yarn bundle. Adhesives have also been used to laminate sheets or layers of fabric or provide a resinous backing to tufted fabric such as carpets. Such coatings generally reduce abrasion induced damage such as pilling but are accompanied by adverse effects on the mechanical or tactile properties of the fabric reducing consumer appeal.

[0008] There is an ongoing need for processes and fabric treatments which improve the resistance of fabrics constructed from multifiber yarn to abrasion damage.

Summary

[0009] We have now found that the resistance to abrasion damage of fabric which includes a multifiber yarn can be significantly improved without unduly compromising fabric mechanical or tactile properties by contacting the fabric with a dilute aqueous particulate dispersion of an adhesive polymer so that the particles provide discrete, spaced apart sites of adhesion between fibers of the yarn.

[0010] There is provided a process for improving the resistance to abrasion damage of a fabric including a multifiber yarn, the process comprising contacting the fabric with an aqueous dispersion of particulate adhesive having a concentration in the dispersion of no more than 30% (preferably no more than 10%) by weight of the dispersion to provide take-up of particles of adhesive in the fabric of from 0.0001 % to 5% (preferably 0.0001 to 2%) by weight of the dry weight of the fabric. [001 1 ] The adhesive is typically heat activated at a temperature of from 50°C to 160°C (preferably 60°C to 130°C) and the process further comprises heating the fabric following contact with the dispersion at a temperature to heat activate the adhesive. Preferably the adhesive is a hot melt adhesive and the fabric is heated to provide a temperature above the melting point of the adhesive.

[0012] The fabric is preferably subject to padding in the presence of the dispersion as this enhances contact between the adhesive dispersion and the multifiber yarn and aids in penetration of the dispersion medium into the interstitial spaces between fibers within the yarn.

[0013] Fine particles of adhesive may be urged into the interstitial spaces between fibers of the yarn to provide discrete, spaced apart sites of adhesion between fibers within the multifiber yarn. The presence of the discrete, spaced apart sites of adhesion between fibers within the multifiber yarn significantly improves the resistance to abrasion damage. This is generally evident in reduced incidence of fuzzing and pilling. Despite the presence of adhesive the discrete, spaced apart feature of the adhesion can be controlled to result in little or no detrimental effect on the feel of the fabric.

[0014] In one set of embodiments the yarn comprises fibers of dimension of at least 5 microns and the aqueous dispersion comprises fine particles of maximum dimensions sufficiently small preferably no more than 1 micron, more preferably from 1 nm to 500 nm, most preferably 20 nm to 200 nm, to penetrate the multifiber yarn and provide discrete, spaced apart sites of adhesion in the interstitial spaces between fibers of the yarn.

[0015] In a further set of embodiments the aqueous dispersion of particles include microfibers which on melting adhere to the outside of the yarn to bind fibers within the yarn at discrete, spaced apart sites of adhesion between fibers. Once again the discrete, spaced apart feature of the adhesion results in little or no detrimental effect on the feel and comfort of the fabric. The use of the aqueous dispersion of fine particles, microfibers or both treatments can be controlled to provide excellent resistance to abrasion induced damage with little or no effect on fabric feel. [0016] The fabric may be treated with an aqueous dispersion of fine particles and an aqueous dispersion of microfibers in sequential treatment or alternatively in a preferred set of embodiments the aqueous dispersion comprises both fine particles and microfibers. Thus the dispersion may comprise both (a) particles of maximum dimensions sufficiently small preferably no more than 1 micron, more preferably from 1 nm to 500 nm, most preferably 20 nm to 200 nm, to penetrate the multifiber yarn and provide discrete, spaced apart sites of adhesion in the interstitial spaces between fibers of the yarn and (b) microfibers having a length to diameter aspect ratio of at least 5 (preferably at least 10 such as from 5 to 5000 or from 10 to 500) which provide discrete and spaced apart sites of adhesion on the outside of the yarn. The use of this combination provides two mechanisms for inhibiting abrasion induced damage which together enable the resistance to be optimised while maintaining fabric feel.

[0017] In a further set of embodiments there is provided an abrasion resistant fabric including a multifiber yarn comprising discrete and spaced apart sites of adhesion between constituent fibers of the multifiber yarn wherein the adhesion is provided by at least one of (a) particles of adhesive within the interstitial spaces between fibers within the yarn providing discrete sites of adhesion between the fibers and (b) microfibers of adhesive providing discrete and spaced apart sites of adhesion on the outer surface of the yarn.

Detailed Description

[0018] The term "fiber" as used herein includes fibers of extreme or indefinite length (i.e., filaments) and fibers of short length (i.e. staple). The term "yarn" as used herein means a continuous strand of fibers.

[0019] The term "fabric" as used herein includes a textile structure composed of mechanically interlocked fibers. The structure can be a nonwoven, woven, knitted, crocheted, knotted or felted fabric. The fabric in this invention is generally a woven, knitted, crocheted, knotted or felted fabric and typically woven, knitted or crocheted.

[0020] The term "multifiber yarn" as used herein means a yarn comprised of a plurality of individual fibers or strands, typically at least 20 such as at least 50 or 50 to 150 fibers. The multifiber yarn which is most significantly improved by the invention contains staple fibers such as a blend of natural staple fibers and synthetic fibers. [0021 ] As used herein, the terms "polymer" and "polymeric material" generally include homopolymers, copolymers, such as for example, block, graft, random and alternating copolymers, terpolymers, etc. and blends and modifications thereof.

Furthermore, unless otherwise specifically limited, the term "polymer" shall include all possible geometrical configurations of the molecule. These configurations include, but are not limited to isotactic, syndiotactic and random symmetries.

[0022] The term "adhesive" is employed to designate a formulation which is capable of bonding other substances together by surface attachment. The adhesive may be a pressure sensitive adhesive or heat activated adhesive such as a hot melt adhesive.

[0023] The term "dispersion" encompasses any form of solid (solid referring to solid at room temperature of about 20 ^Q C) dispersed in a liquid medium including, for example, latexes, emulsions, colloidal suspensions, and the like.

[0024] The term "aqueous dispersion" refers to a dispersion carrier that is primarily water. However, incidental organic solvents, such as those present in additives and commercially available components, may be present. Thus, the aqueous dispersion of adhesive is at least substantially free of organic solvents. Preferably, however, "aqueous dispersion" refers to an at least 80%w/w water carrier preferably at least 90% such as at least 95% or about 100% water of the carrier component of the aqueous dispersion composition.

[0025] The term "heat-activated adhesive" as used in the present invention refers to an adhesive which exhibits adhesiveness as a result of heating. The heating is carried out, for example, at about 50°C to 160°C (preferably 60°C to 130°C).

Examples of the heat-activated adhesive include (1 ) hot-melt adhesives that exhibit adhesiveness with solidifying by cooling after melting by heating, and (2)

thermosetting adhesives that exhibit adhesiveness through curing by heating. Among them, hot-melt adhesives are preferred.

[0026] The term "hot melt adhesive" or "hot melt adhesive composition", as used hereinafter, means an adhesive or adhesive composition which is used for adhesion which is effected by melting an adhesive or adhesive composition by heating. Generally in the present invention the hot melt adhesive is heated to melting following incorporation in the fabric.

[0027] The term "(meth)acrylic acid" is shorthand notation for methacrylic acid and/or acrylic acid. Likewise, the term "(meth)acrylate" is shorthand notation for methacrylate and/or acrylate.

[0028] Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other features, integers, steps or components, or group thereof.

[0029] The term pill in the context of the present application refers to a small visible ball of fibers that forms on a piece of fabric. Pill (or pilling) may also be used as a verb for the formation of such balls.

[0030] The term "Staple" refers to fiber of discrete length and may be of any composition. A continuous fiber such as natural silk or polyester is referred to as "filament" rather than staple fiber.

[0031 ] The process comprises contacting the fabric with an aqueous dispersion comprising adhesive having a concentration in the dispersion of no more than 30 %. The adhesive concentration generally may be no more than 20% and typically no more than 10% w/w of the aqueous dispersion composition. The concentration of the adhesive is generally at least 0.01 % w/w particularly at least 0.1 % w/w of the composition such as 0.01 %w/w to 30% w/w, 0.05% to 20% w/w, 0.05% w/w to 10% w/w, 0.1 % w/w to 5% w/w 0.5% w/w to 20% w/w, 0.5% w/w to 10% w/w, 0.5% w/w to 5%w/w. Conveniently the concentration is in the range of 1 % w/w to 30% w/w such as 1 % w/w to 20% w/w, 1 % w/w to to 10% w/w or 1 % w/w to 5% w/w.

[0032] The fabric is treated with the composition to provide a content of the particles of adhesive in the fabric is from 0.0001 % to 5 % by weight of the dry weight of the fabric. Typically the treated fabric will comprise from 0.0001 % w/w to 2% w/w and typically 0.0001 % w/w to 1 .5 % w/w adhesive based on the dry weight of the treated fabric such as 0.001 %w/w to 2% w/w, 0.001 %w/w to 1 .5% w/w, 0.01 % w/w to 2% w/w, 0.01 % w/w to 1 .5% w/w or 0.01 % w/w to 1 % w/w of the dry weight of the fabric.

[0033] The take up of the particulate adhesive from the aqueous dispersion of adhesive will depend on the concentration of the particulate adhesive in the aqueous dispersion, contact time and conditions, the particle size and compatibility of the adhesive with the fibers present in the multifilament yarn. The use of adhesive of similar polarity to at least a proportion of fibers present in the yarn may assist in uptake resulting in a higher proportion of particulate adhesive in the fabric than would otherwise be the case. In this respect it is often desirable to use adhesive comprising a polymer of amphiphilic nature including non-polar and polar groups.

[0034] The process may utilise an aqueous dispersion of adhesive particles of a heat activated adhesive having a melting point of from 50°C to 1 60°C, preferably 60°C to 1 30°C and the process may comprise heating the fabric following contact with the dispersion at a temperature above the melting point of the adhesive whereby the particles provide discrete and spaced apart sites of adhesion between the fibers of the yarn.

[0035] The specific chemical nature of the adhesive is not narrowly critical and a person of skill in the art will readily be able to select adhesive for use in the process of the invention having regard to the formulation requirements, nature of the fibers present in the yarn and required durability. Specific examples of chemical classes of adhesive include ethylene-vinyl acetate (EVA) copolymers; ethylene-(meth)acrylate copolymers including copolymers of ethylene and (Ci to C ₄ alkyl) (meth)acrylate such as ethylene-butyl (meth)acrylate, ethylene-ethyl (meth)acrylate, and ethylene-methyl (meth)acrylate copolymers (ethylene n-butyl acrylate (EnBA) is a preferred

copolymer); ethylene-(meth)acrylic acid (EAA) and ethylene-ethyl acetate (EEA); polyolefins (PO) (polyethylene (usually LDPE but also HDPE (HDPE has higher melting point and better temperature resistance), atactic polypropylene (PP or APP); polybutene-1 , oxidized polyethylene, amorphous polyolefin (APO/APAO) polymers; polyamides, polyesters; thermoplastic polyurethane (TPU); polyurethanes (PUR), or reactive urethanes; styrene block copolymers (SBC), also called styrene copolymer adhesives and rubber-based adhesives. adhesives may in addition to the primary polymer contain tackifiers, waxes, mixtures of two or more types of adhesive and mixtures of one or more adhesives with other additives to modify the melting point and/or the bonding properties of the adhesive. In general the preferred class of adhesives are the ethylene (meth)acrylate copolymers and in particular copolymers of ethylene and acrylic and/or methacrylic acid and ionomers of such copolymers.

[0036] The adhesive in one set of embodiments is a copolymer of ethylene and at least one of an acrylate and methacrylate monomer which may, for example be acrylic acid, methacrylic acid, (Ci to C ₄ alkyl) acrylate, (Ci to C ₄ alkyl) methacrylate. The polymer acid groups may be at least partly neutralised by ammonia or an amine, particularly a tertiary amine such as NN, dimethylethanolamine. The total content of acrylate and methacrylate monomers is typically from 5% to 40% by weight of the copolymer.

[0037] The more preferred adhesives are copolymers of ethylene and acrylic acid optionally at least partly neutralised with a nitrogen base such as ammonia or amines, particularly tertiary amines including N,N-di(Ci to C ₄ alkyl) Ci to C ₄ alkanolamines such as Ν,Ν-dimethylethanolamine. These adhesives are preferred due to the melting profile which may be provided and the resilience and effective bonding provided by the incorporation of particles of this adhesive from an aqueous

dispersion. Suitable example of such copolymers are commercially available under a range of trade names including NUCREL ^® (DuPont Packaging & Industrial Polymers), PRIMACOR ^® (Dow Chemical or SK Global Chemical Co., LTD) LUGALVAN ^® DC and CARBOSET ^® 560. Copolymers of ethylene and acrylic acid often referred to as Poly(ethylene-co-acrylic acid) or PEAA which may be in the form of ionomers are typically synthesized via the high pressure, free radical copolymerization of ethylene and acrylic acid. This process results in a highly branched polymer with random placement of the constituent monomers along the backbone. For example, one particularly useful adhesive is an ethylene acrylic acid copolymer having an acrylic acid content of from 5% to 40% w/w of the copolymer, preferably from 5%w/w to 30% w/w of the polymer such as from 5% to 25% w/w of the copolymer. We have found that a content of about 20% w/w of the ethylene acrylic acid is particularly useful in the present invention. For 5 weight percent PEAA copolymers, the melting

temperature is about 100°C. Increasing the acid content to 20 wt% decreases the melting temperature to about 75 ^Q C to about 80°C. [0038] Polymers of ethylene and acrylic acid may be in the form of ionomers formed with a nitrogen base such as ammonia or an amine, particularly a tertiary amine such as Ν,Ν-dimethylethanolamine. The presence of the nitrogen base provides a self-dispersing polymer which avoids the use of additives to form or stabilise the dispersion in an aqueous medium. LUGALVAN ^® DC and CARBOSET ^® 560 products are examples of such dispersions

[0039] The aqueous dispersion of the particulate adhesive may be applied to the fabric by various industrial fabric treatment methods, such as immersing the fabric in the aqueous dispersion or spraying the dispersion onto the fabric, at a temperature lower than the melting point of the adhesive.

[0040] The process may include a step in which the fabric is subject to padding in the presence of the dispersion to enhance contact between the adhesive dispersion and the multifiber yarn. The padding may be carried out using padders of type known in the industry for the application of chemicals such as sizing. The dispersion may be applied to the fabric by spray application or by dipping the fabric in the aqueous dispersion which may, for example, be contained in a trough. Typically, the padder includes a pair of squeeze rolls which may be described as a mangle. In one embodiment the fabric is submerged in the aqueous dispersion, for example by passing beneath a roll in a trough of aqueous dispersion, and then through squeeze rolls. The process may comprise double dipping of the fabric if desired, with squeeze rolls positioned before and after the second dipping. There are a number of factors which control the amount of dispersion remaining in the fabric including the squeeze pressure of the rolls, fabric construction and the absorptive nature of the fabric.

Adjustment in the pickup of dispersion and hence the particulate uptake into the fabric can be controlled by the pressure applied by the padding process, the concentration of the adhesive in the dispersion and the contact time. The padding process also assists in providing an even distribution of the particles of adhesive within the fabric and in particular within the structure of the multifiber yarn.

[0041 ] The use of particles of size sufficiently small compared with the fibers of the yarn results in a significant proportion of adhesive particles in the interstitial spaces between fibers of the yarn to provide discrete and spaced apart sites of adhesion between fibers within the multifiber yarn. [0042] For example, the yarn typically comprises fibers of dimension of at least 5 microns and the dispersion comprises particles of maximum dimensions sufficiently small, (preferably no more than 1 micron, more preferably from 1 nm to 500 nm, most preferably 20 nm to 200 nm), may penetrate the multifiber yarn and provide discrete and speced apart sites of adhesion in the interstitial spaces between fibers of the yarn.

[0043] In one set of embodiments the aqueous dispersion particles of adhesive includes microfibers of adhesive which on melting adhere preferentially to the outside of the yarn to bind fibers within the yarn. The microfibers generally have a length of at least 5 microns such as in the range of from 1 to 5000 microns (preferably 5 to 5000 microns or 5 to 1000 microns) average length and from 0.01 to 5 microns average thickness. In a preferred embodiment, the microfibers are 5 to 300 microns average length and 0.01 to 3 microns average thickness. In one set of embodiments the aspect ratio (length/thickness) of the microfibers is at least 5:1 such as at least 10:1 or at least 50:1 . Examples of the process for preparation of microfibers which may be used to prepare microfibers of a suitable adhesive are described in International Publication WO2013/056312.

[0044] The adhesion of microfibers between two or more fibers, generally on the outside of the fabric yarn, significantly improves the resistance to fuzzing, pilling, and abrasion-related damage by reinforcing the exterior of the yarn bundle of fibers.

[0045] In one set of embodiments the process further comprises treating the fabric with a further treatment, preferably selected from the group consisting of , binder treatments (such as polyurethane binder coatings), water repellency treatments, fabric softening treatments and further anti-pilling treatments. The further treatment may be applied before during or after treatment of the fabric with the aqueous dispersion of adhesive. In some embodiments the further treatment may be present in the aqueous dispersion composition and form a further dispersed phase. The present invention provides discrete, spaced apart, sites of adhesion between the fibers of the yarn and therefore allows other treatment to contact the fibers on the outside of the yarn and/or the inside of the yarn bundle where treatments penetrate the yarn bundle. This combination is difficult to achieve for conventional treatments which provide a homogeneous coating film on the fibers because the coating film will in many instances counteract or inhibit activity arising from the further treatment. For instance, deposition of polyurethane film-forming binders on the surface of a textile, together with durable water repellency treatments would interfere in the process and tend to homogenise, with loss of repellency performance. In general water repellency treatments are much less effective if the film formed by the treatment is contaminated with other components.

[0046] In one set of embodiments the aqueous dispersion is used in a process which further comprises applying a water repellent treatment. In one set of

embodiments the water repellent treatment is selected from the group consisting of fluorocarbon resins such as C8, C6 and C4 fluorocarbon compositions, water repellent hyperbranched polymers, polysiloxanes, micro- and nano-textured coatings and waxes and paraffin,

[0047] The microfibers, in one set of embodiments, have an aspect ratio of at least 5 (such as from 5 to 5000 or from 10 to 1000).

[0048] In one set of embodiments the dispersion comprises both (a) particles of maximum dimension sufficiently small (preferably no more than 1 micron, more preferably from 1 nm to 500 nm, most preferably 20 nm to 200 nm) to penetrate the multifiber yarn and provide discrete and spaced apart sites of adhesion in the interstitial spaces between fibers of the yarn and (b) microfibers having an aspect ratio of at least 5 (preferably at least 10 such as from 5 to 5000 or from 10 to 1000) which on melting preferentially adhere to the outside of the yarn to bind fibers within the yarn.

[0049] In embodiments where both (a) and (b) are used the weight ratio of (a) : (b) is generally from 1 :100 to 100:1 (preferably 1 : 10 to 10:1 ).

[0050] In one set of embodiments the yarn is a staple yarn comprising fibers of discrete length. The process of the invention is particularly useful in this embodiment as it assists in binding the fibers together to inhibit fibers from untwisting from the yarn or the fiber ends becoming detached and prone to fuzzing and pilling.

[0051 ] In one set of embodiments the multifiber yarn comprises a mixture of continuous filaments and fibers of discrete length. The yarn may be a staple yarn comprising continuous filaments of at least one synthetic polymer (preferably selected from polyesters, polyurethanes and polyacrylics) and at least one natural fiber of discrete length (preferably selected from cotton, cashmere and wool). As mentioned above such yarns are prone to fuzzing and pilling and the process inhibits the rupture of fibers and retains the fiber bundle so as to improve the resistance to defects from abrasion without a significant effect on fiber or fabric handling, feel and comfort. The process can be used to treat fabric which would otherwise fuzz and pill and

consequently be considered to be of low quality by the consumer. Such fabric may have a tendency to fuzz and pill due the factors such as a fine denier, the content of strong synthetic fibers (which tend to result in fiber ends which retain fuzz and pills), yarns of low twist, hairy yarns or open ended spun yarns with a loose construction or a combination of these factors. The process is also advantageous in allowing the fabric, which may otherwise fuzz or pill and be considered of poor quality, to be treated to reduce these problems and hence be perceived by the purchaser as of higher quality than would otherwise be the case in absence of the treatment.

[0052] The fabric is formed of a multifiber yarn. While a multifiber yarn contains at least 3 fibers the multifiber yarn typically comprises a bundle of at least 20 fibers (preferably at least 50 fibers such as 50 to 300 fibers or about 50 to about 150 fibers).

[0053] The fabric treated in accordance with the invention generally exhibits a reduction in fuzzing and pilling. The extent of the reduction in the pilling of the fabric may be measured using testing standard methods such as ISO 12945-2: fuzzing and pilling (Martindale). The textile treated in accordance with the invention preferably has a reduction in pilling score [Martindale (SUM) ISO 12945-2] of at least 10%.

[0054] In instances where the fabric is a woven yarn it is common practice to apply a size to the yarn, particularly the warp yarn to improve weaving efficiency. Unprotected yarn will generally not withstand the mechanical stresses caused by weaving. The weaving process and the yarn quality are improved by the presence of size and lubricant during weaving. Size is used as a coating in a significant amount and is a major residue impurity that needs to be removed following weaving. The size is generally a water soluble polymer such as starches and water soluble synthetic polymers such as water soluble polyesters and water soluble acrylic polymers

Following weaving the size is removed from the fabric in a desizing operation using a water bath and in some cases additional chemicals to strip the size from the fabric yarn. In general, where the process of the present invention is conducted with woven fabric the fabric is treated following desizing. In cases where the fabric is knitted a sizing step is not required and in most cases the fabric may be treated by the process following knitting.

[0055] Examples of the fibers which may be present in the multifiber yarn include polyester, Kevlar, modacryl, nomex, nylon, spandex, rayon, acetate, polypropylene, polyamide, polyurethane, acrylic, or vinylon, semi-synthetic fiber such as acetate or rayon, regenerated fiber such as viscose rayon or copper ammonia rayon, natural fiber such as cotton, hemp, flax, sisal, wool, silk, cashmere, alpaca, llama, mohair and fiber in which any of these is blended and combination of these fibers. In one set of embodiments the yarn comprises one or more fiber types selected from the group consisting of wool, cotton, polyester, polyamide and polyacrylic.

[0056] The process of the invention is particularly advantageous for fabrics of spun yarns made from staple fibers and blends. Although soft and flexible feel is provided by staple fiber yarns they are inherently fragile to abrasion as a result of processing and wear leading to abrasion-related damage such as fuzzing and pilling. In one set of embodiments the yarn comprises blends of synthetic fiber, which may be present as continuous filaments and staple yarn of natural fiber such as cotton, wool, cashmere or the like.

[0057] In a further set of embodiments the invention provides an abrasion- damage resistant fabric including a multifiber yarn comprising discrete and spaced apart sites of adhesion between constituent fibers of the multifiber yarn wherein the adhesion is provided by at least one of (a) particles of adhesive within the interstitial spaces between fibers within the yarn and (b) microfibers of adhesive positioned on the outer surface of the yarn.

[0058] In one embodiment the fabric includes a staple yarn comprising fibers of discrete length. The multifiber yarn may comprise a mixture of continuous filaments and fibers of discrete length, such as a staple yarn comprising continuous filaments of at least one synthetic polymer and at least one natural fiber of discrete length. Brief Description of Drawings

[0059] In the drawings:

[0060] Figure 1 is a flow diagram showing one embodiment of the invention;

[0061 ] Figure 2 is a schematic drawing of a cross section of a multifiber spun yarn from a fabric treated with a conventional film-forming binder to inhibit abrasion damage;

[0062] Figure 3 is a schematic drawing of a cross section of a multifiber spun yarn from a fabric treated with a conventional treatment with silicic acid particles to inhibit abrasion damage.

[0063] Figure 4 is a schematic drawing of a cross section of a multifiber spun yarn from a fabric treated in a accordance with the invention process using a fine particle adhesive aqueous dispersion providing penetration of particles into the spun yarn bundle of fibers

[0064] Figure 5 is a schematic drawing of a cross section of a multifiber spun yarn from a fabric treated in a accordance with the invention process using an aqueous dispersion of a microfiber adhesive providing adhesive bonding of fibers on the outside of the yarn bundle.

[0065] Figure 6 is a schematic drawing of a cross section of a multifiber spun yarn from a fabric treated in a accordance with the invention process using a fine particle adhesive aqueous dispersion in combination with a conventional polyurethane binder treatment providing penetration of adhesive particles of the dispersion into the spun yarn bundle of fibers and a film of polyurethane binder throughout the yarn.

[0066] Figure 7 is a schematic drawing of a cross section of a multifiber spun yarn from a fabric treated in a accordance with the invention process using a fine particle adhesive aqueous dispersion in combination with a conventional silicic acid particle treatment providing penetration of adhesive particles of the dispersion into the spun yarn bundle of fibers and a composition selected from particles of modified colloidal polysilicic acid with water soluble silicon oil and aqueous solution of colloidal silica with water soluble silicon oil the particles of silicic acid or silica providing friction between fibers on the outside of the yarn bundle.

[0067] With reference to Figure 1 an embodiment of the process for treating fabric for reducing susceptibility to abrasion damage is shown. The fabric (10) of knitted or woven spun staple yarn is soaked (20) in an aqueous dispersion of 0.0001 % w/w to 5% w/w particulate of ethylene co-acrylic acid copolymer adhesive comprising at least one of (a) particles of maximum dimension sufficiently small (preferably no more than 1 micron, more preferably from 1 nm to 500 nm, most preferably 20 nm to 200 nm) to penetrate the multifiber yarn and provide discrete and spaced apart sites of adhesion in the interstitial spaces between fibers of the yarn and (b) microfibers having an aspect ratio of at least 5 (preferably at least 10 such as from 5 to 5000 or from 10 to 1000). The soaked fabric is passed through a padding mangle (30) which enhances contact between the fibers of the yarn and dispersion and removes excess dispersion from the fabric. The drained fabric is heat treated (40) for example in a drying oven to a temperature sufficient to melt the adhesive and in the range of 50 ^Q C to 160 ^Q C (preferably 60 ^Q C to 130 ^Q C) and the heat treated fabric is allowed to cool (50) to provide a abrasion resistant fabric (60) in which the fibers of the mutifiber yarn are bonded by discrete and spaced apart sites of adhesion. The process may be part of the finishing process in fabric manufacture.

[0068] When the process is used in part of a process of woven fabric manufacture the process will generally be conducted after the sizing and removal of sizing from the woven fabric. The aqueous dispersion may be applied in sequence and in

combination with other finishing treatments such as fabric softeners. Fabric softeners are recognised as generally exacerbating the problem of abrasion induced damage and a combination of the process of the invention and fabric softening will significantly improve the resistance to abrasion induced damage. Examples of softeners sometimes used in treating fabric during finishing include silicones and quats. In an alternative embodiment the process is used in treatment of fabric following the normal finishing process. The aqueous dispersion may also be used in a manner that is compatible with functional treatments such as water repellency to provide increased abrasion resistance without negatively impacting the repellency functionality, which would otherwise be difficult for conventional film-based binder treatments. [0069] With reference to Figure 2 there is shown a yarn (100) comprising a multiplicity of staple fibers (1 10) and optionally including synthetic fibers where the yarn has been treated with a film coating composition of polyurethane producing a homogeneous film matrix (1 20) of binder extending throughout the yarn (100) bundle. While such treatment reduces abrasion induced damage there is a significant reduction in the feel of the fabric so as to be less attractive to consumers than the fabric without the binder treatment.

[0070] With reference to Figure 3 there is shown a yarn (100) comprising a multiplicity of staple fibers (1 10) and optionally including synthetic fibers where the yarn has been treated with a coating composition selected from modified colloidal polysilicic acid with water soluble silicon oil and aqueous solution of colloidal silica with water soluble silicon oil. The silicic acid or silica particles (130) are deposited on the outside of the yarn fiber bundle (100) to provide adhesion between fibers (1 10) by increased friction which tends to be detrimental to fiber mechanical strength in the long term, and generally has a negative impact on mechanical handle and comfort.

[0071 ] With reference to Figure 4 there is shown a yarn (100) comprising a multiplicity of staple fibers (1 10) and optionally including synthetic fibers (1 10) where the yarn (100) treated with an aqueous dispersion of adhesive particles of size about 0.2 micrometers to provide a yarn bundle in which adhesive particles (140) at discrete and spaced apart sites within interstitial spaces between fibers (1 10) of the yarn (100).

[0072] With reference to Figure 5 there is shown a yarn (100) comprising a multiplicity of staple fibers (1 10) and optionally including synthetic fibers where the yarn treated with an aqueous dispersion of microfibers (150) having an aspect ratio of at least 5 which adhere to the outside of the yarn (100) to bind fibers (1 10) within the yarn (100).

[0073] With reference to Figure 6 there is shown a yarn (100) comprising a multiplicity of staple fibers (1 10) and optionally including synthetic fibers where the yarn (100) treated with an aqueous dispersion of adhesive particles of size about 0.2 micrometers to provide a yarn bundle (100) in which adhesive particles (140) at discrete and spaced apart sites within interstitial spaces between fibers (1 10) of the yarn (100) and a film coating composition of polyurethane producing a homogeneous film matrix (120) of binder extending throughout the yarn bundle (100).

[0074] With reference to Figure 7 there is shown a yarn (100) comprising a multiplicity of staple fibers (1 10) and optionally including synthetic fibers where the yarn (100) treated with an aqueous dispersion of adhesive particles of size about 0.2 micrometers to provide a yarn bundle (100) in which adhesive particles (140) at discrete and spaced apart sites within interstitial spaces between fibers (1 10) of the yarn (100). The yarn (100) is also treated with a coating composition selected from modified colloidal polysilicic acid with water soluble silicon oil and aqueous solution of colloidal silica with water soluble silicon oil. The silicic acid or silica particles (130) are deposited on the outside of the yarn fiber bundle (100) to provide adhesion between fibers (1 10) by increased friction

[0075] The following examples illustrate the invention in further detail but the examples should not be construed as limiting the scope of the invention as described herein.

[0076] Examples

[0077] Examples 1 to 15 - Summary

[0078] The Examples detailed below describe treatments in accordance with the invention in which a range of fabrics are treated with dispersions of particulate adhesive. Details of the composition components, process used and testing regime are summarised in Table 1 with further explanation in specific Examples. Detailed results for the Examples are listed in Table 3.

Table 1

Column heading Description

Fabric Composition of the fabric. WO = wool; CO = cotton; PES

= polyester; PA = polyamide, PAN = polyacrylic

Structure Woven (W) or knit (K) construction

Note Mechanical pilling/abrasion test method. 1 = ISO 12945-2:

fuzzing and pilling (Martindale); 2 = ISO 12947 abrasion resistance (Martindale).

Treatment Composition (% wof) Fabric treatment prepared with laboratory padding method followed by drying in a lab stenter/dryer. Composition prepared as an aqueous mixture of different components (selected from those listed Table 2). The amounts of components of the composition are provided on the basis of % weight of fabric (% wof). Fabrics that were tested without treatment for reference comparison are denoted as V for untreated.

Laundry (40°C) Number of home laundry cycles (ISO 6330) at 40°C prior to testing

Pilling score /5 (# Martindale The visual pill appearance score (scale of 5, averaged) for cycles) various number of Martindale turn cycles (appearance graded at 125, 500, 1000, 2000 and 5000 with some samples evaluated through 7000 cycles). The 'SUM' column is the cumulative total of the scores for the various cycles with a higher sum indicating better pilling/abrasion resistance.

[0079] The acronyms used in the Examples for components are listed in Table 2.

Table 2

Preparation of Poly(ethylene-co-acrylic acid) (PEAA) Fibers

[0080] A 20%wt/vol solution of poly(ethylene-co-acrylic acid) (PEAA)

(DowChemical, Primacor® 59901 ) was prepared in diluted ammonia (9% ammonia in water), stirring overnight at 95 ^° C. This solution was then diluted with pH 12 aqueous ammonia, to prepare solutions of varying polymer concentration. 1 -butanol was chosen as the dispersing solvent (250 ml). A high speed mixer (T50 UltraTurrax - IKA) equipped with high shear impeller was used in the procedure. The stirring head was inserted in a beaker of similar diameter. The dispersing solvent was first introduced in the beaker, the stirring was started and 3 ml of the polymer solution were then quickly injected in the gap between the mixer's head and the wall of the beaker by using a 3ml_ syringe with a 27G needle, injection speed: 20mL/min. Stirring was maintained for a certain time then stopped. The fibers thus obtained are dispersed in an aqueous medium to form an aqueous dispersion of the microfibers.

[0081 ] Example 1

[0082] A wool/polyester blend knit fabric was treated with different melt adhesive components. One sample was treated with 3% DP68-1 (melt adhesive fiber dispersion) or 1 % DP68-2 (melt adhesive particle dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). Both fabrics show an increased resistance to pill formation compared to an untreated reference fabric.

[0083] Example 2

[0084] A cotton/linen blend woven fabric was treated with 2.7% DP68-2 (melt adhesive particle dispersion). The fabric was characterized for abrasion resistance with the Martindale method (ISO 12947). The treated fabric shows increased resistance to visible abrasion pill formation compared to an untreated reference fabric.

[0085] Example 3

[0086] A polyacrylic knit fabric was treated with various loadings (2%, 2.5% and 3% wof) of DP68-2 (melt adhesive particle dispersion). The fabric was characterized for abrasion resistance with the Martindale method (ISO 12947). The treated fabrics at the various loadings show increased resistance to visible abrasion pill formation compared to an untreated reference fabric. [0087] Example 4

[0088] A cashmere knit fabric was treated with different melt adhesive

components in combination with a conventional silicone softener. One treatment was based on 2% silicone softener with 3% DP68-2 (melt adhesive particle dispersion) while a second treatment was based on 2% silicone softener with 7% DP68-1 (melt adhesive fiber dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). Both treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric with the DP68-1 treatment showing a higher level of robustness over 2000 turn cycles.

[0089] Example 5

[0090] A wool knit fabric was treated with different melt adhesive components in combination with a conventional silicone softener. One treatment was based on 2% silicone softener with 3% DP68-2 (melt adhesive particle dispersion) while a second treatment was based on 2% silicone softener with 7% DP68-1 (melt adhesive fiber dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). Both treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric over 2000 turn cycles.

[0091 ] Example 6

[0092] A wool knit fabric was treated with 2% silicone softener with 3% DP68-2 (melt adhesive particle dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). The treated fabric shows an increased resistance to pill formation compared to an untreated reference fabric over 2000 turn cycles.

[0093] Example 7

[0094] A wool knit fabric was treated with different melt adhesive components in combination with a conventional silicone softener. One treatment was based on 2% silicone softener with 3% DP68-2 (melt adhesive particle dispersion) while a second treatment was based on 2% silicone softener with 7% DP68-1 (melt adhesive fiber dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). Both treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric over 2000 turn cycles. [0095] Example 8

[0096] A polyester/polyamide knit fabric was treated with two conventional treatments in comparison to the melt adhesive particle dispersion (DP68-2). One conventional treatment was based on 1 % of a silicic acid (SA) product in combination with 3.5% of a polyacrylate acid ester (PAA) product. A second conventional treatment was based on 6% of a polyurethane (PU) product. A third treatment was based on 3.5% DP68-2 (melt adhesive particle dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). The fabrics were characterized both initially and after 20x laundry cycles. All treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric. After laundry all treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric over 1000 turn cycles.

[0097] Example 9

[0098] A cotton knit fabric was treated with two conventional treatments in comparison to the melt adhesive particle dispersion (DP68-2). One conventional treatment was based on 1 % of a silicic acid (SA) product in combination with 3.5% of a polyacrylate acid ester (PAA) product. A second conventional treatment was based on 6% of a polyurethane (PU) product. A third treatment was based on 3.5% DP68-2 (melt adhesive particle dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). The fabrics were characterized both initially and after 20x laundry cycles. All treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric both before and after laundry.

[0099] Example 10

[0100] A cotton/polyester blend knit fabric was treated with two conventional treatments in comparison to the melt adhesive particle dispersion (DP68-2). One conventional treatment was based on 1 % of a silicic acid (SA) product in combination with 3.5% of a polyacrylate acid ester (PAA) product. A second conventional treatment was based on 6% of a polyurethane (PU) product. A third treatment was based on 3.5% DP68-2 (melt adhesive particle dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). The fabrics were characterized both initially and after 20x laundry cycles. All treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric both before and after laundry.

[0101 ] Example 11

[0102] A cotton knit fabric was treated with two conventional treatments in comparison to the melt adhesive particle dispersion (DP68-2). One conventional treatment was based on 0.7% of a silicic acid (SA) product in combination with 2.5% of a polyacrylate acid ester (PAA) product. A second conventional treatment was based on 4% of a polyurethane (PU) product. A third treatment was based on 2.5% DP68-2 (melt adhesive particle dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). All treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric.

[0103] Example 12

[0104] A cotton knit fabric was treated with two conventional treatments in comparison to the melt adhesive particle dispersion (DP68-2). One conventional treatment was based on 0.7% of a silicic acid (SA) product in combination with 2.5% of a polyacrylate acid ester (PAA) product. A second conventional treatment was based on 4% of a polyurethane (PU). A third treatment was based on 2.5% DP68-2 (melt adhesive particle dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 1 2945-2). All treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric.

[0105] Example 13

[0106] A cashmere knit fabric was treated with 1 .5% silicone softener with 5% DP68-1 (melt adhesive fiber dispersion). The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). The treated fabric shows an increased resistance to pill formation compared to an untreated reference fabric over 2000 turn cycles.

[0107] Example 14

[0108] A polyester knit fabric was treated with various combinations of a conventional polyurethane (PU) product, a conventional ethoxylated carboxylic acid (ECA) softener, a melt adhesive fiber dispersion (DP68-1 ), and a melt adhesive particle dispersion (DP68-2). The PU treatment was applied at both 4% and 8% wof. The ECA softener was applied by itself at 3% wof and also at 1 .5% in combination with 4% PU. The melt adhesive particle dispersion (DP68-2) was applied by itself at 3% wof and also at 1 .5% in a combination with 4% PU. The melt adhesive fiber dispersion (DP68-1 ) was applied by itself at 15% and 25% wof and also at 12.5% in a combination with 4% PU. The samples were characterized for pilling tendency with a modified Martindale method (ISO 12945-2). All treated fabrics show an increased resistance to pill formation compared to an untreated reference fabric. Treatments based on combinations of 4% conventional PU with melt adhesive dispersions (DP68- 1 or DP68-2) generally show an increased performance compared to the components used individually.

[0109] Example 15

[01 10] A polyester knit fabric was treated with various combinations of a

conventional polyurethane (PU) product, a conventional ethoxylated carboxylic acid (ECA) softener, a melt adhesive fiber dispersion (DP68-1 ), and a melt adhesive particle dispersion (DP68-2). The PU treatment was applied at both 4% and 8% wof. The ECA softener was applied by itself at 3% wof and also at 1 .5% in combination with 4% PU. The melt adhesive particle dispersion (DP68-2) was applied by itself at 3% wof and also at 1 .5% in a combination with 4% PU. The melt adhesive fiber dispersion (DP68-1 ) was applied by itself at 15% and 25% wof and also at 12.5% in a combination with 4% PU. The fabric was characterized for abrasion resistance with the Martindale method (ISO 12947). Treatments based on combinations of 4% conventional PU with melt adhesive dispersions (DP68-1 or DP68-2) generally show an increased performance compared to the untreated reference fabric and fabrics treated with the individually components.

[01 1 1 ] The results of the Examples and testing are shown in Table 3, parts (a), (b) and (c). Table 3 (a)

Table 3 (b)

Table 3 (c)