HK1164389B - An article comprising garment comprising a knit - Google Patents

Description

Article comprising a garment comprising a knitted fabric

Background of the invention.

Technical Field

Included are multicomponent elastic fibers comprising a polyurethaneurea and a polyurethane composition prepared by a solution spinning process, such as a spandex (spandex) spinning process, the cross-section of the fiber comprising at least two separate regions having definable boundaries, wherein at least one region defined by the boundaries of the cross-section comprises a polyurethaneurea or a polyurethane composition. One region of the fiber includes a fusibility improvement additive that enhances adhesion to itself or to a substrate.

Background

Polyurethane or polyurethane urea (PU or PUU) elastomeric yarns can provide high stretchability (stretch), good recovery from stretch (extension), and good fit (fit) to articles made from them such as weft knit (weft knit), warp knit (warp knit), woven, non-woven, and other textiles. However, for articles containing PU or PUU elastic yarns, repeated stretching, scratching, or cutting often causes problems with longitudinal raveling, running, and crimping. These problems include: ladder-like cracks and gaps are created, the elastomeric yarn can slip (slip out), the open path (grin) or the yarn displacement (fray) at the cut edge and cause fabric hemming, which impairs the uniformity and appearance of the article. During cutting and sewing, under repeated stretching, the PU or PUU elastic yarn will easily come out of the seam (seam) and cause a loss of fabric stretchability, so called "slip" or seam failure. Although such effects occur on elastic yarns other than PU or PUU yarns, these effects are particularly significant for PU or PUU elastic yarns due to their high stretch ability. Furthermore, for some articles, high steam or heat setting efficiency is required, especially for hosiery (hosiery) applications.

Considerable efforts have been made to develop heat-fusible and steam-settable PU or PUU elastic yarns. US patent application publications nos. 2006/0030229a1 and 2008/0032580a1 disclose a type of highly fusible polyurethane elastic filament obtained by melt spinning a polymer synthesized by reacting an isocyanate terminated prepolymer prepared by the reaction of a polyol and a diisocyanate with a hydroxyl terminated prepolymer prepared by the reaction of a polyol, a diisocyanate and a low molecular weight diol. The fusible PU filaments have a melting point of 180 ℃ or less. A dry heat treatment at 100% elongation at 150 ℃ for 45 seconds will cause the PU filaments to fuse to each other or to other elastic or inelastic filaments at the crossing points. However, the low melting point of the PU filaments results in unsatisfactory heat resistance, such that creep occurs in normal consumer applications, resulting in garment arching (bagging).

There is a need for improved spandex yarns that provide meltability, steam-set ability, and provide excellent stretch resilience during garment manufacturing to overcome one or more of the deficiencies of existing fibers.

Summary of The Invention

The present invention relates to products and processes for producing multicomponent spandex fibers with enhanced functionality. Included are solvent spun polyurethanes or polyurethaneureas that provide higher stretch/recovery characteristics and thermal resilience, which can be prepared by a two-component spinning process, include excellent fusibility additives and result in fusible yarns suitable for fusing applications such as machine direction raveling of yarns, prevention of slippage, and enhanced adhesion.

In some embodiments, an elastic, multicomponent, solution-spun fiber comprises a cross-section, wherein at least a first region of the cross-section comprises an elastomeric polyurethane or polyurethaneurea or a mixture thereof; and the second region comprises an elastomeric polyurethane or polyurethane urea or mixtures thereof and at least one fusibility improvement additive.

The fiber may have one or more filaments, such as a single filament, double filament (two filaments), three filaments, and so forth. When the fiber has more than one filament, each filament can comprise a multi-component cross-section having two or more regions.

In another embodiment, the fabric comprises an elastic, multi-component, solution-spun fiber comprising a cross-section, wherein at least a first region of the cross-section comprises at least one elastomeric polyurethane, a polyurethaneurea composition, or mixtures thereof; and the second region comprises at least one elastomeric polyurethane, polyurethaneurea composition, or mixtures thereof and at least one fusibility improvement additive.

Also included is a process for preparing a fusible, elastic, multicomponent, solution-spun fiber, the process comprising:

(a) providing first and second polymer solutions;

(b) combining the solutions through distribution plates (distribution plates) and orifices to form filaments having a cross-section;

(c) extruding the filaments through a common capillary; and

(d) removing the solvent from the filaments;

wherein the cross-section includes a boundary between the polymer solutions;

wherein each of the first and second polymer solutions independently comprises an elastomeric polyurethane, a polyurethaneurea, or a mixture thereof; and

wherein the second polymer solution comprises a fusibility improvement additive;

wherein the fusible, elastic, multicomponent, solution-spun fiber comprises a plurality of region cross-sections, wherein a first polymer solution corresponds to a first region of the cross-section and a second polymer solution corresponds to a second region of the cross-section.

In a further embodiment, the fiber comprises an elastic, multi-component, solution-spun fiber comprising a cross-section, wherein at least a first region of the cross-section comprises an elastomeric polyurethane, or a polyurethaneurea, or a mixture thereof; and a second region comprising an elastomeric polyurethane, or a polyurethaneurea, or a mixture thereof, and at least one fusibility improvement additive comprising at least one low temperature melting polyurethane having a melting point of about 100 ℃ to about 180 ℃; and

wherein the first region comprises an elastomeric polyurethane having a high melting point of about 190 ℃ to about 250 ℃.

Drawings

Fig. 1 shows an example of a fiber cross-section that can be achieved in some embodiments.

Fig. 2 is a schematic of a cross-section of a spinneret plate according to some embodiments.

Fig. 3 is a schematic of a cross-section of a spinneret plate according to some embodiments.

Fig. 4 is a schematic of a cross-section of a spinneret plate according to some embodiments.

FIG. 5 is a depiction of differential scanning calorimetry results for the fiber of example 1.

The scan was from-100 ℃ to 350 ℃ at a rate of 10 ℃/min.

Fig. 6 is an SEM micrograph of a fused yarn of some embodiments.

Fig. 7 shows some embodiments of plain stitch (stitch) knitted structures.

Figure 8 illustrates an alternate course (alternate course) knit structure according to some embodiments.

FIG. 9 shows an alternate course knit structure with drop stitches (misled stich) that can be used with some embodiments.

FIG. 10 shows an alternate course knit structure with tuck stitch (tuck switch) that may be used with some embodiments.

Detailed Description

Definition of

The term "multicomponent fiber" as used herein refers to a fiber having at least two separate and distinct regions of different composition (with discernible boundaries), i.e., two or more regions of different composition that are contiguous along the length of the fiber. This is different from polyurethane or polyurethaneurea mixtures where more than one composition is blended to form a fiber with no clear and continuous boundaries along the length of the fiber. The terms "multicomponent fiber" and "multicomponent fiber" are synonymous and are used interchangeably herein.

The term "compositionally different" is defined to include two or more compositions of different polymers, copolymers or blends or two or more compositions with one or more different additives, wherein the polymers included in the compositions may be the same or different. Two comparative compositions are also "compositionally different" when they include different polymers and different additives.

The terms "boundary", "(a plurality of) boundary" and "boundary region" are used to describe the point of contact between different regions of a cross-section of a multicomponent fiber. The contact point is "well defined" with minimal or no overlap between the components of the two regions. When there is an overlap between the two regions, the boundary region will comprise a mixture of the two regions. This blended region may be a separate, uniformly blended portion (section) with a separate boundary between the blended boundary region and each of the other two regions. In addition, the boundary region may include a gradient: the composition of a first region of higher concentration contiguous with the first region to a second region of higher concentration contiguous with the second region.

As used herein, "solvent" refers to organic solvents such as Dimethylacetamide (DMAC), Dimethylformamide (DMF) and N-methylpyrrolidone.

The term "solution spinning" as used herein includes processes for preparing fibers from solution, which can be wet spinning or dry spinning processes, both of which are common techniques for fiber production.

Low melting Polyurethane (PU) compositions (Tm <180 ℃) that provide good steam-set ability and excellent adhesive properties typically result in poor creep resistance, low strength, and poor tensile resilience. Furthermore, this low melting PU composition is not suitable for fiber forming processes and high temperature textile processing requirements. Some embodiments of the present invention combine superior stretch and recovery properties in a multicomponent fiber structure, such as a bicomponent fiber structure, based on a solution spun polyurethane/polyurethaneurea composition having a low melting binder formulation. This includes the case where the low melting polyurethane composition is bonded to a region of the fiber, such as a sheath, where the fiber is fused to other fibers, such as other bicomponent fibers.

The performance of polyurethane block copolymers depends on the phase separation of the urethane and polyol segments, such that hard urethane domains (domains) act as crosslinking points (crosslinks) in the matrix of the soft segments. The urethane domains are controlled by the amount and quality of the chain extender selected. Commercially important diol chain extenders include, without limitation, ethylene glycol, 1, 3-Propanediol (PDO), 1, 4-butanediol (1,4-BDO or BDO), and 1, 6-Hexanediol (HDO). All of these glycol chain extenders form polyurethanes that phase separate well and form well defined hard segment domains and are all suitable for thermoplastic polyurethanes, with the exception of ethylene glycol. Since the urethane formed is disadvantageously degraded at high hard segment levels. Table 1 lists typical hard segment melting point ranges for polyurethanes formed from some common chain extenders. Processing temperatures above 200 ℃ are disadvantageous for conventional TPU compositions due to thermal degradation and the concomitant loss of properties during processing. In addition, PUs formed from compositions having high hard segment melting points have traditionally yielded improved elasticity and thermal resilience and are more desirable for textile processing. Polyurethane fibers with high hard segment melting points can be produced solely from conventional solution spinning processes to achieve excellent stretch/recovery properties.

Various different polyurethane or polyurethaneurea compositions can be used in accordance with the invention in either or both of the first region and the second region. Additional regions may also be included. Useful polyurethane/polyurethaneurea compositions are described below.

One embodiment provides a thermally fusible and steam-settable spandex elastic yarn obtained from solution spinning (dry spinning or wet spinning). The fibers comprise a monofilament structure or a multifilament structure. Each filament of the fiber (or the fiber itself for a monofilament) is a bicomponent fiber having a discernible region along the cross-section of the fiber, such as a sheath-core or side-by-side configuration. The core is a first region and the sheath is a second region. Additional regions may be included to provide different cross-sections, such as a combination of a side-by-side configuration with a sheath-core configuration, or a combination of a sheath-core configuration with additional sheath regions.

For fusible fibres, a particularly useful composition for the second region (which may be a sheath) may include:

A. a polymer mixture wherein the first component comprises at least one polyurethane having a high melting point, polyurethanes having a melting point of about 190 ℃ to about 250 ℃, and those polyurethanes having a melting point of about 200 ℃ or higher and a fusibility improvement additive such as a low temperature melt polyurethane. Useful low melting point polyurethanes include those having a melting point of about 50 ℃ to about 150 ℃, particularly those having a melting point below 120 ℃; or

B. A mixture wherein the first component comprises at least one polyurethane having a high melting point, such as a polyurethane having a melting point of about 190 ℃ to about 250 ℃, as well as those polyurethanes having a melting point of about 200 ℃ or higher and at least one binder material or fusibility improver for subsequent bonding of substrates, wherein the binder material is a fusibility improver; or

C. A mixture of at least one polyurethane and at least one viscosity fusibility improvement agent.

Combinations and permutations of A, B and C are also envisaged. Additional additives may also be included.

For fusible fibres, particularly useful compositions of the first region (which may be the core) may include:

1) at least one polyurethane having a high melting point, such as polyurethanes having a melting point of about 190 ℃ to about 250 ℃, and those polyurethanes having a melting point of about 200 ℃ or higher; or

2) A mixture of a polyurethane having a high melting point of 200 to 250 ℃ and a polyurethane having a low melting point of less than 180 ℃, or,

3) a mixture of at least one polyurethane and at least one polyurethaneurea; or

4) Polyurethaneureas, including those having a melting point greater than 240 ℃.

The bicomponent fibers of some embodiments can include a variety of ratios of the first region to the second region. The second region (which can also be a sheath in a sheath-core structure) can be present in an amount of about 1% to about 60% based on the weight of the fiber, including about 1% to about 50% by weight of the fiber, about 10% to about 35% by weight of the fiber, and about 5% to about 30% by weight of the fiber.

The fusible fibers of some embodiments can have a steam setting efficiency of greater than 50%. The fibers can also have a fusion strength greater than 0.15 cN/dtex.

Some embodiments are multicomponent or bicomponent fibers comprising a solution-spun polymeric composition comprising a polyurethane, a polyurethaneurea, or a mixture thereof. The composition of the different regions of the multicomponent fiber comprises different polymer compositions: the polymers are different, the additives are different, or both the polymers and the additives are different. Multicomponent fibers having a solution spun portion and a melt spun portion are also included.

Polyurethane urea and polyurethane composition

A polyurethaneurea composition for making fibers or long chain synthetic polymers comprising at least 85% by weight of a segmented polyurethane. Typically, these include polymeric diols which are reacted with diisocyanates to form NCO-terminated prepolymers ("capped diols") which are then dissolved in a suitable solvent such as dimethylacetamide, dimethylformamide or N-methylpyrrolidone and then (secondarily) reacted with difunctional chain extenders. When the chain extender is a diol, the polyurethane is formed in a second step (and prepared without a solvent). When the chain extender is a diamine, polyurethaneureas, a subclass of polyurethanes, are formed. In the preparation of polyurethane urea polymers capable of being spun into spandex, the diol is chain extended by the subsequent reaction of the hydroxyl end groups with a diisocyanate and one or more diamines. In each case, the diol must be chain extended to obtain a polymer having the desired properties, including viscosity. If desired, dibutyl tin dilaurate, stannous octoate, mineral acids, tertiary amines such as triethylamine, N, N' -dimethylpiperazine, and the like, and other known catalysts can be used to assist in the capping step.

Suitable polymeric diol components include polyether diols, polycarbonate diols, and polyester diols having number average molecular weights of about 600 to about 3,500. Mixtures of two or more polymeric glycols or copolymers can be included.

Examples of polyether diols which can be used include those having two or more hydroxyl groups obtained from the ring-opening polymerization and/or copolymerization of ethylene oxide, propylene oxide, oxetane, tetrahydrofuran and 3-methyltetrahydrofuran, or from the polycondensation of polyols having less than 12 carbon atoms in each molecule (e.g., diols or diol mixtures) such as ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 2-dimethyl-1, 3-propanediol, 3-methyl-1, 5-pentanediol, 1, 7-heptanediol, 1, 8-octanediol, 1, 9-nonanediol, 1, 10-decanediol and 1, 12-dodecanediol. Linear difunctional polyether polyols are preferred, and poly (tetramethylene ether) glycols having a molecular weight of from about 1,700 to about 2,100, such as Terathane 1800(INVISTA of Wichita, KS) having a functionality of 2, are one example of particularly suitable glycols. The copolymer can include poly (tetramethylene-co-ethyleneether) glycol.

Examples of the polyester polyol that can be used include those having two or more hydroxyl groups produced by the polycondensation reaction of an aliphatic polycarboxylic acid with a low-molecular-weight polyol having not more than 12 carbon atoms in each molecule or a mixture thereof. Examples of suitable polycarboxylic acids are malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, and dodecanedicarboxylic acid. Examples of suitable polyols for the preparation of the polyester polyols are ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, neopentyl glycol, 3-methyl-1, 5-pentanediol, 1, 7-heptanediol, 1, 8-octanediol, 1, 9-nonanediol, 1, 10-decanediol and 1, 12-dodecanediol. Linear difunctional polyester polyols having a melting temperature of from about 5 ℃ to about 50 ℃ are examples of specific polyester polyols.

Examples of polycarbonate polyols which can be used include those polycarbonate diols having two or more hydroxyl groups which are produced by polycondensation of phosgene, chloroformates, dialkyl or diallyl carbonates and low molecular weight aliphatic polyols having not more than 12 carbon atoms in each molecule or mixtures thereof. Examples of suitable polyols for the preparation of the polycarbonate polyols are diethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, neopentyl glycol, 3-methyl-1, 5-pentanediol, 1, 7-heptanediol, 1, 8-octanediol, 1, 9-nonanediol, 1, 10-decanediol and 1, 12-dodecanediol. Linear difunctional polycarbonate polyols having a melting temperature of from about 5 ℃ to about 50 ℃ are examples of specific polycarbonate polyols.

The diisocyanate component can also include a single diisocyanate or a mixture of different diisocyanates including diphenylmethane diisocyanate (MDI) isomer mixtures containing 4,4 '-methylene bis (phenyl isocyanate) and 2, 4' -methylene bis (phenyl isocyanate). Any suitable aromatic or aliphatic diisocyanate can be included. Examples of diisocyanates that can be used include, but are not limited to, 4,4 ' -methylenebis (phenyl isocyanate), 2,4 ' -methylenebis (phenyl isocyanate), 4,4 ' -methylenebis (cyclohexyl isocyanate), 1, 3-diisocyanato-4-methyl-benzene, 2,2 ' -toluene diisocyanate, 2,4 ' -toluene diisocyanate, and mixtures thereof. Examples of specific polyisocyanate components include Mondur ML (Bayer), Lupranate MI (BASF), and Isonate 50O, P' (Dow Chemical), and combinations thereof.

For polyurethaneureas, the chain extender may be water or a diamine chain extender. Combinations of different chain extenders may be included depending on the desired properties of the polyurethaneurea and the resulting fiber. Examples of suitable diamine chain extenders include: hydrazine; 1, 2-ethylenediamine; 1, 4-butanediamine; 1, 2-butanediamine; 1, 3-butanediamine; 1, 3-diamino-2, 2-dimethylbutane; 1, 6-hexanediamine; 1, 12-dodecanediamine; 1, 2-propanediamine; 1, 3-propanediamine; 2-methyl-1, 5-pentanediamine; 1-amino-3, 3, 5-trimethyl-5-aminomethylcyclohexane; 2, 4-diamino-1-methylcyclohexane; n-methylamino-bis (3-propylamine); 1, 2-cyclohexanediamine; 1, 4-cyclohexanediamine; 4, 4' -methylenebis (cyclohexylamine); isophorone diamine; 2, 2-dimethyl-1, 3-propanediamine; m-tetramethylxylylenediamine; 1, 3-diamino-4-methylcyclohexane; 1, 3-cyclohexane-diamine; 1, 1-methylene-bis (4, 4' -diaminohexane); 3-aminomethyl-3, 5, 5-trimethylcyclohexane; 1, 3-pentanediamine (1, 3-diaminopentane); m-xylylenediamine; and Jeffamine @ (Texaco).

When a polyurethane is desired, the chain extender is a diol. Examples of diols that may be used include, but are not limited to, ethylene glycol, 1, 3-propanediol, 1, 2-propanediol, 3-methyl-1, 5-pentanediol, 2, 2-dimethyl-1, 3-propanediol, 2,2, 4-trimethyl-1, 5-pentanediol, 2-methyl-2-ethyl-1, 3-propanediol, 1, 4-bis (hydroxyethoxy) benzene, and 1, 4-butanediol, hexanediol and mixtures thereof.

Monofunctional alcohols or primary/secondary monofunctional amines may optionally be included to control the molecular weight of the polymer. Mixtures of one or more monofunctional alcohols with one or more monofunctional amines may also be included.

Examples of the monofunctional alcohol which can be used in the present invention include at least one member selected from the following: aliphatic and cycloaliphatic primary and secondary alcohols having from 1 to 18 carbon atoms, phenols, substituted phenols, ethoxylated alkyl phenols and ethoxylated fatty alcohols having a molecular weight of less than about 750 (including molecular weights of less than 500), hydroxylamines, hydroxymethyl and hydroxyethyl substituted tertiary amines, hydroxymethyl and hydroxyethyl substituted heterocyclic compounds, and combinations thereof, including furfuryl alcohol, tetrahydrofurfuryl alcohol, N- (2-hydroxyethyl) succinimide, 4- (2-hydroxyethyl) morpholine, methanol, ethanol, butanol, neopentyl alcohol, hexanol, cyclohexanol, cyclohexanemethanol, benzyl alcohol, octanol, octadecanol, N, N-diethylhydroxylamine, 2- (diethylamino) ethanol, 2-dimethylaminoethanol, and 4-piperidineethanol, and combinations thereof.

Examples of suitable monofunctional dialkylamine blocking agents include: n, N-diethylamine, N-ethyl-N-propylamine, N-diisopropylamine, N-tert-butyl-N-methylamine, N-tert-butyl-N-benzylamine, N-dicyclohexylamine, N-ethyl-N-isopropylamine, N-tert-butyl-N-isopropylamine, N-isopropyl-N-cyclohexylamine, N-ethyl-N-cyclohexylamine, N-diethanolamine, and 2,2,6, 6-tetramethylpiperidine.

Other polymers

Other polymers that may be used in the multicomponent and/or bicomponent fibers of the present invention include other polymers that are soluble or have limited solubility, or the other polymers can be included in particulate form (e.g., fine particles). The polymer may be dispersed or dissolved in a polyurethane or polyurethaneurea solution, or coextruded with a solution spun polyurethane or polyurethaneurea composition. The result of the coextrusion can be bi-or multicomponent fibers having side-by-side, concentric sheath-core, or eccentric sheath-core cross-sections, where one component is a polyurethaneurea solution and the other component contains additional polymer. Examples of other polymers include, inter alia, low melting polyurethanes (as described above), polyamides, acrylics, polyaramides, and polyolefins. In some embodiments, the non-polyurethane polymer can be a fusibility improver, particularly when the polymer has a melting point below about 150 ℃.

Other polymers included in the multicomponent fiber include nylon 6, nylon 6/6, nylon 10, nylon 12, nylon 6/10, and nylon 6/12. PolyolefinsIncluding from C₂－C₂₀A polyolefin prepared from monomers. This includes copolymers and terpolymers, such as ethylene-propylene copolymers. Examples of useful polyolefin copolymers are disclosed in U.S. Pat. No. 6,867,260 to Datta et al, which is incorporated herein by reference.

Fiber cross-sectional structure

Various different cross-sections may be used in some embodiments of the invention. These include bicomponent or multicomponent concentric or eccentric sheath-core configurations and bicomponent or multicomponent side-by-side configurations. A unique cross-section is contemplated as long as the cross-section includes at least two separate regions. Alternative cross-sections may be orange-peel (pie-slice configuration) or similar eccentric sheath-core configurations, where the sheath only partially surrounds the core. In other words, the second region of the cross-section may partially or completely surround the first region. Examples of different suitable cross-sections are shown in fig. 1.

The meltable polymer may be included as a major or sole component of the sheath or side-by-side or alternative structure, without a separate fusibility improver (where the meltable polymer has the desired melting point).

The overall fiber cross-section shown in fig. 1 has a first region and a second region of different composition. 44 dtex/3 filament yarn is shown in FIGS. 1A and 1B, while 44 dtex/4 filament yarn is shown in FIGS. 1C and 1D. The first region includes pigment and the second region does not include pigment in each filament yarn. FIGS. 1A and 1B include 50/50 sheath-core cross-sections; FIG. 1C includes an 17/83 sheath-core cross-section; and FIG. 1D includes 50/50 side-by-side cross-sections.

Each of the sheath-core and side-by-side cross-sections includes a boundary region between at least two compositionally different polyurethaneurea compositions. These regions appear to have well-defined boundaries in each of these figures, but the boundaries may include blended regions. When the boundary comprises a blended region, the boundary itself is a distinct region that is a mixture of the composition of the first and second (or third, fourth, etc.) regions. This mixture may be a homogenous mixture or may include a concentration gradient from the first region to the second region.

Additive agent

The types of additives optionally included in the polyurethaneurea composition are listed below. Including exemplary and non-limiting lists. However, additional additives are well known in the art. Examples of additives include: antioxidants, uv stabilizers, colorants, pigments, crosslinkers, phase change materials (paraffin), antimicrobial agents, minerals (i.e., copper), microencapsulated additives (i.e., aloe vera, vitamin E gel, aloe vera, seaweed, nicotine, caffeine, flavorants or aromas), nanoparticles (i.e., silica or carbon), calcium carbonate, flame retardants, detackifiers, chlorine degradation resistant agents, vitamins, drugs, fragrances, conductive additives, dyeability additives and/or dyeing aids (e.g., quaternary ammonium salts). Other additives that may be added to the polyurethaneurea composition include adhesion promoters and fusibility improvers, antistatic agents, creep resistance agents, optical brighteners, coagulants, electrical conducting agents, luminescent agents, lubricants, organic and inorganic fillers, preservatives, texturing agents, thermochromic additives, insect repellents, as well as wetting agents, stabilizers (hindered phenols, zinc oxides, hindered amines), slip agents (silicone oils) and combinations thereof.

The additives may provide one or more beneficial properties, including: dyeability, hydrophobicity (i.e., Polytetrafluoroethylene (PTFE)), hydrophilicity (i.e., cellulose), friction control, chlorine resistance, degradation resistance (i.e., antioxidants), adhesion and/or fusibility (i.e., binders and adhesion promoters), flame retardancy, antimicrobial properties (silver, copper, ammonium salts), barrier properties, electrical conductivity (carbon black), tensile properties, color, fluorescence, recyclability, biodegradability, fragrance, tack control (i.e., metal stearate), tactile properties, setting ability, thermal regulating properties (i.e., phase change materials), nutriceuticals, matting agents such as titanium dioxide, stabilizers such as hydrotalcite, mixtures of huntite and hydromagnesite, UV screeners, and combinations thereof.

The additives can be included in any amount suitable to achieve the desired effect.

Several additives may be used as the fusibility improvement agent having a low melting point, including in some embodiments. These additives include moisture curing, thermal bonding and reactive hot melt grade (hot-melt grades) linear aromatic thermoplastic polyurethanes based on polyethers, polyesters, polycarbonates and polycaprolactones or mixtures thereof. Examples of specific commercially available products include, inter alia, Mor-Melt (R-5022) (Rohm and Haas), Pellathane 2103C (Dow), Desmopan 5377, Desmopan 9375A, Texin DP7-1197 (Bayer Material Science), Pearlond 104, 106,122,123 (Merquinsa Mercados Qu i Microos, S.L), and TPUA-252A (TPUCO, Taiwan). The fusibility improver can be included in any suitable amount necessary to achieve the desired fusibility of the fiber. The fusibility improvement additive may be included in the sheath or the second region of the fiber in an amount of from about 10% to about 90% by weight of the sheath or the second region, including an amount of from about 30% to about 60% by weight of the sheath or the second region. The weight percent of the fusibility improvement additive based on the total weight of the multicomponent or bicomponent fiber will depend on the weight ratio of the core or first region to the sheath or second region of the fiber. In some cases, the second dermatome may itself be a fusible polymer with or without an additional fusibility enhancer.

Device for measuring the position of a moving object

Bicomponent fibers are typically prepared by a melt spinning process. The devices used in these processes may be adapted for use in solution spinning processes. Dry spinning and wet spinning are well known solution spinning processes.

Suitable references (incorporated herein by reference) relating to fibers and filaments, including those of man-made bicomponent fibers, are for example:

a. Fundamentals of Fibre Formation--The Science of Fibre Spinning and Drawing, Adrezij Ziabicki, John Wiley and Sons, London/New York, 1976；

b. Bicomponent Fibres, R Jeffries, Merrow Publishing Co. Ltd, 1971；

c. Handbook of Fiber Science and Technology, T. F. Cooke, CRC Press, 1993；

similar references include U.S. Pat. Nos. 5,162,074 and 5,256,050 (incorporated herein by reference) which describe methods and apparatus for bicomponent fiber production.

Extrusion of the polymer through a die to form fibers is carried out using conventional equipment, such as extruders, gear pumps, and the like. It is preferred to supply the polymer solution to the die using a separate gear pump. When mixing the additives required for functionality, the polymer mixture is preferably mixed in a static mixer, for example, upstream of a gear pump, to obtain a more uniform dispersion of the components. Prior to extrusion, each spandex solution can be heated separately by means of a jacketed vessel of controlled temperature and filtered to improve spinning yield.

In the illustrated embodiment of the invention, two different polymer solutions are introduced into a segmented, jacketed heat exchanger operating at 40-90 ℃. The extrusion dies and plates are arranged according to the desired fiber configuration and are illustrated in a sheath-core configuration in fig. 2, an eccentric sheath-core configuration in fig. 3, and a side-by-side configuration in fig. 4. In all cases, the component streams were combined just above the capillary. The preheated solution is guided from the supply ports (2) and (5) through a screen (7) to the distribution plate (4) and onto a spinning plate (9) which is positioned by spacers (8) and supported by nuts (6).

The extrusion dies and plates described in figures 2, 3 and 4 can be used with a conventional spandex spin cell as described in U.S. patent No. 6,248,273, incorporated herein by reference.

The bicomponent spandex fiber can also be prepared through separate capillaries to form separate filaments that are subsequently coagulated to form individual fibers.

The features and advantages of the present invention will be more fully shown by the following examples, which are provided for purposes of illustration and are not to be construed as limiting the invention in any way.

Method for producing fibers

The fibers of some embodiments are produced by spinning (wet or dry) a polyurethane or polyurethane-urea polymer from a solution containing a common urethane polymer solvent (e.g., DMAc). The polyurethane or polyurethaneurea polymer solution may include any of the compositions or additives described above. The polyurethaneureas are prepared by reacting an organic diisocyanate with a suitable diol in a diisocyanate to diol molar ratio in the range of 1.6 to 2.3, preferably in the range of 1.8 to 2.0, to produce a "capped diol". The capped glycol is then reacted with a mixture of diamine chain extenders. In the formed polymer, the soft segment is the polyether/urethane portion of the polymer chain. These soft segments exhibit a melting point of less than 60 ℃. The hard segment is the polyurethane/urea portion of the polymer chain; these have a melting point above 200 ℃. The hard segments represent from 5.5 to 12%, preferably from 6 to 10%, of the total weight of the polymer. The polyurethane polymer is prepared by reacting an organic diisocyanate with a suitable diol in a diisocyanate to diol molar ratio in the range of 2.2 to 3.3, preferably in the range of 2.5 to 2.95, to produce a "capped diol". The capped glycol is then reacted with a mixture of glycol chain extenders. The hard segment is a polyurethane segment of a polymer chain; these have a melting point range of 150-. The hard segments can represent from 10 to 20%, preferably from 13 to 7.5%, of the total weight of the polymer.

In one embodiment of making fibers, a polymer solution containing 30-40% polymer solids is metered through a distribution plate and desired arrangement of orifices to form filaments. The distribution plates are arranged to combine the polymer streams in one of a concentric sheath-core, eccentric sheath-core, and side-by-side arrangement and then extruded through a common capillary tube. The extruded filaments are dried by the introduction of hot inert gas at 300 ℃ to 400 ℃ and according to a gas to polymer mass ratio of at least 10:1 and are drawn at a speed of at least 400 m/min (preferably at least 600m/min) and then taken up at a speed of at least 500 m/min (preferably at least 750 m/min). All examples given below were carried out at an extrusion temperature of 80 ℃ in a hot inert gas atmosphere at a take-up speed of 762 m/min. Standard process conditions are well known in the art.

Yarns formed from elastic fibers according to the present invention generally have a tenacity at break of at least 0.6 cN/dtex, an elongation at break of at least 400%, and a modulus at no load at 300% elongation of at least 27 mg/dtex.

The yarns and fabrics can be prepared from the elastic multicomponent fibers described herein by any conventional means. The elastic yarn can be covered with a second yarn such as a hard yarn. Suitable hard yarns include, inter alia, nylon, acrylic, cotton, polyester and mixtures thereof. Covered (covered) yarns can include single covered (single covered), double covered (double covered), air covered, core spun and core twisted yarns.

The elastic yarns of some embodiments can be included in a variety of structures such as knitted fabrics (warp and weft), woven fabrics, and non-woven fabrics. These may be used in hosiery, socks, shirts, underwear, swimwear, lower body garments (bottoms) and non-woven fabric hygiene structures.

In some embodiments, various knit structures are useful. The knitted fabric can comprise plain knit stitches as shown in fig. 7, wherein some embodiments of multicomponent spandex 14 can be used in each course, covered with a hard yarn such as nylon (plated), or covered with nylon. The knit fabric can also include an alternating course knit in which the multicomponent spandex 14 is used in covered or uncovered (bare) form and every other course having hard yarns 16 covered by hard yarns, such as nylon. A drop stitch fig. 9 construction or tuck stitch fig. 10 construction may also be used where the multicomponent spandex 14 is used in each course and contacts the multicomponent spandex 14A of the other course.

When fusing or bonding of the yarns is desired, this can be achieved by exposure to heat and/or at a static pressure of up to 3.5 bar (depending on the composition of the fusibility improver). The heating can be applied as steam or dry heat. Suitable fusing conditions for hosiery can include exposure to temperatures of from about 90 ℃ to about 140 ℃, including from about 105 ℃ to about 135 ℃ for from about 3 seconds to about 60 seconds when steam heat is used, and from 165 ℃ to about 195 ℃ for from about 3 seconds to about 60 seconds when dry heat is used. Suitable fusing conditions can vary depending on a number of factors, including the selected fusibility improvement additive, polymer chemistry, linear density of the yarn, and fabric construction (i.e., knitting, weaving, etc.), among others.

For hosiery, the fabric is exposed to various process conditions, including exposure to heat and/or pressure. Thus, a separate heat-setting/fusing process is not required, as heat-setting of the fabric will also result in fusing of the yarns containing the fusibility improvement agent or other binder.

The strength and elastic properties of the spandex fibers in the examples were measured according to the general method of ASTM D2731-72. Three filaments, 2-inch (5-cm) measurement length and 0-300% elongation cycle were used in each measurement. These samples were cycled five times at a constant elongation rate of 50 cm/min. Load power (M200) -the stress applied to spandex fiber during initial elongation-was measured at 200% elongation for the first cycle and reported as gram-force for a given denier. The unloaded power (U200) is the stress at 200% elongation for the fifth unloaded cycle and is also reported in grams-force. Percent elongation at break and strength were measured in the sixth elongation cycle. Percent set (percent set) was also measured for samples that underwent five 0-300% elongation/relaxation cycles. The percent set,% S, is calculated as

%S = 100(Lf – Lo)/Lo

Where Lo and Lf are the filament (yarn) lengths when straightened without tension before and after 5 elongation/relaxation cycles, respectively.

To determine steam set (which simulates hosiery processing and setting operations), a sample of selected length having Yo (suitably 10 cm) under straight, tensionless conditions is stretched to 3 times its original length for about 2 minutes, and then relaxed. This simulates a coating operation in which spandex is drawn while being coated with a common yarn. The spandex test specimen thus stretched and relaxed is then placed in a boiling water bath for 30 minutes. Exposure to boiling water simulates the staining procedure. The sample was then removed from the boiling water bath, dried, and stretched to twice its post-bath relaxation length. While under this stretching condition, the sample was exposed to a steam atmosphere at 121 ℃ for 30 seconds. The steam treatment simulates the setting of hosiery. After removal from the steam atmosphere, the sample was allowed to dry and its straight tensionless length Yf was measured. The steam set fraction (SS,%) is then calculated according to the following formula:

%SS = 100 (Yf-Yo)/Yo

yarn fusibility was measured by placing a 15cm long sample on a triangular adjustable frame, where the vertex (vertex) is centered on the frame and the triangle has two equal side lengths of 7.5 cm. A second filament of the same length is placed on the frame from the opposite side so that the two yarns intersect and cross at a single point of contact.

The fiber was relaxed to 5cm and then exposed to a bath for one hour, rinsed, air dried, and then exposed to a dye bath for 30 minutes, rinsed, and air dried.

The fibrous frame was adjusted from 5cm length to 30cm length and then exposed to steam at 121 ℃ for 30 seconds, cooled for 3 minutes and then relaxed. The yarns are removed from the frame and transferred to a tensile testing machine where each yarn is clamped at one end with the point of contact between the clamps. The yarn was elongated at 100%/minute and the force to break the contact point (gram-force) was recorded as the weld strength.

The features and advantages of the present invention will be more fully shown by the following examples, which are for purposes of illustration and are not to be construed as limiting the invention in any way.

Examples

For examples 1-3 below, fibers were produced by dry spinning a high melting polyurethane elastomeric polymer from a solution of N, N-dimethylacetamide (DMAc) CAS No 127-19-50. In order to provide sufficient thermal stability to the final fiber, a high melting point polyurethane polymer is prepared as follows and used as the basis for the core and sheath composition. By heating a mixture of MDI ((benzene, 1, 1-methylenebis [ isocyanato- ] CAS No [26447-40-5]) and PTMEG (poly (oxy-1, 4-butanediyl), alpha-hydro-omega-hydroxy, CAS No 25190-06-1) of 2000 number average molecular weight to 75 ℃ for 2 hours, this prepolymer solution is then chain extended by the addition of sufficient ethylene glycol (CAS No 107-21-1) to increase the 40 ℃ falling ball solution viscosity to 4000 poise. The polymerization was terminated by the addition of a monofunctional alcohol (1-butanol (CAS No 71-36-3)).

The polymer solution containing 35-40% polymer solids is metered through the desired arrangement of distribution plates and orifices to form filaments. The distributor plates are arranged to combine the polymer streams in a concentric sheath-core arrangement and then extruded through a common capillary. The extruded filaments are dried by the introduction of hot inert gas at 320 ℃ to 440 ℃ and according to a gas to polymer mass ratio of at least 10:1 and are drawn at a speed of at least 400 m/min (preferably at least 600m/min) and then taken up at a speed of at least 500 m/min (preferably at least 750 m/min). Yarns formed from these elastic fibers generally have a tenacity at break of at least 1 cN/dtex, an elongation at break of at least 400%, and an M200 of at least 0.2 cN/dtex.

Example 1:

the linear polycaprolactone polyurethane supplied by merquisa Mercados quiimicos, s.l (Pearlbond 122) was dissolved and mixed at 30% by weight with the high melting PU polymer prepared (as described above) to form a 35% DMAc solution and extruded as a skin component. The core solution consisted of a high temperature PU polymer in DMAc and was mixed with the sheath solution in a 4:1 ratio to form 22 dtex twin filament yarn. The product was collected at 700 m/min and wound up on a roll at 850 m/min after coating with silicone oil. The product properties including meltability, steam setting efficiency, and tensile properties are listed in table 2. Differential scanning calorimeter trace (fig. 5) illustrates a low melting transition at about 56 ℃ for the fusible additive.

Example 2:

the thermoplastic polyurethane elastomer (ester/ether) supplied by Bayer Material Science, USA (Desmopan 5377A) was dissolved and mixed with the prepared high melting PU polymer (as described above) at 60% by weight to form a 36% DMAc solution and extruded as a sheath component. The core solution consisted of a high melting point PU polymer in DMAc and was mixed with the sheath solution in a 4:1 ratio to form 22 dtex twin filament yarn. The product was collected at 700 m/min and wound up on a roll at 850 m/min after application of the silicone oil. Product properties including meltability, steam setting efficiency, and tensile properties are listed in table 2.

Example 3 (comparative):

the prepared high temperature PU polymer (described above) was extruded as a 39% DMAc solution, without modification, as a sheath and core component in a 4:1 ratio to form 22 dtex twin filament yarn. The product was collected at 700 m/min (drain away) and wound up on a package at 850 m/min after application of a finishing oil of the silicone type. The product properties including meltability, steam setting efficiency, and tensile properties are listed in table 2.

The example yarns (examples 1-3) were covered with 11dtex/7 straight polyamide 66 straight yarn (flat 11dtex/7 filament flat polyamide 66 yarn) on a commercially available Menegatto or ICBT covering machine. The draw down ratio of the elastic yarn was 2.8x and the cover factor (cover factor) was 1500 tpm. The knitted sock sample was knitted on a commercially available knitting machine such as a Lonati 400 circular hosiery knitting machine. The covered yarn is knitted in a course, warp knit construction that allows for fusing of the elastic yarn at each contact point. Sufficient fusing may also be achieved when fusible yarn is included in alternating courses.

After standard operation of the autoclave and apparatus, the garments are set at 110 ℃ and 130 ℃ for 10-60 seconds on standard setting equipment in a steam chamber. Sufficient meltability was tested by placing the garment on a developed panel, which would result in typical stretching during wear. The puncture is formed by causing the elastic yarn to break with a knife or scissors. The hole does not increase in size if the force of the elastic yarn on the form (form) caused by elongation is lower than the force resulting from the fusion of the elastic yarn. If the force of the elastic yarn is higher, the fusion point will not remain intact and the knitted structure will unravel (so-called run-off or machine direction run-off). The longitudinal ravel characteristics of the garment were visually observed and are indicated in table 2. SEM analysis results of bond formation and fusion quality of the knitted hosiery (example 1) are shown in fig. 6, in which the bi-filament component 22 dtex yarn 10 has a fusion point 11 and is surrounded by smaller filaments of the nylon covered yarn 12.

Example 4-meltable skins:

a hot melt crystalline thermoplastic polyurethane binder (Pearlbond 122 available from Merquinsa Mercados Qu i simiios) was prepared as a 35% solution in DMAc as an 50/50 mixture with a conventional segmented polyurethaneurea and then spun into a sheath with a conventional spandex core of the segmented polyurethaneurea to make 44 dtex/3 filament yarn. The total sheath content is 20% based on the weight of the fibre to produce a yarn which is meltable when heated above 80 ℃.

This advantage is that the fibers have excellent fusing characteristics combined with excellent stretch/recovery characteristics. The results of the physical tests (including steam set ratio and fusion strength) are shown in Table 3.

EXAMPLE 5 knitted sock Fabric

Eight fabrics were prepared by using polyamide yarns (nylon) in combination with selected from LYCRA T162 fibers (20 denier) and the fusible bicomponent fibers of example 1 (20 denier). Comparative fabrics A, B, E and F were prepared using LYCRA T162 and inventive fabrics C, D, G and H were prepared using the elastic fibers of example 1.

Knit sock structures were prepared as shown in table 4. The fabric was knitted using a Lonati 400 hosiery knitter using a standard four feed system to produce the structure. Each of fabrics A-H was knitted at 450 rpm. The fabric is designated as an every course plain knit (every court jersey) including plain stitches shown in fig. 7, in which there are elastic yarns 14 in every course. The fabric is designated as an alternating Course Jersey (alternating Course Jersey) comprising an alternating Course structure as shown in fig. 8, in which the elastic yarns 14 are present in every other Course, alternating with hard yarns 16, which in this case are textured polyamide (nylon). The remaining fabric (G and H) comprises a drop-stitch construction as shown in fig. 9, in which hard yarn 16 (textured polyamide) is included with the elastomeric yarn present in every other course, and this elastomeric yarn contacts the elastomeric yarn in the other course. The spandex was either used as bare spandex, indicating that the bare spandex was covered or covered (single layer wrap) with 10 denier/7 filament polyamide straight filament yarn.

Each fabric was then dyed using acid dyes in black and beige/brown colors using standard industry procedures for nylon knit socks. The knit sock is shaped using a commercially available first co. The chamber is then opened and the knitted sock leg is rotated into the drying oven zone. These examples were set with a steam pressure of 2 atmospheres for 20 seconds and then dried in a convection oven chamber set to 200 ° f.

The resistance to laddering (the ability of the fabric to resist laddering or machine direction unraveling after perforation) was tested and the results are also shown in table 4. Fabrics comprising fusible yarns (C, D, G and H) were found to have excellent results.

While there has been described what are presently considered to be the preferred embodiments of the present invention, those skilled in the art will recognize that various changes and modifications may be made thereto without departing from the spirit of the invention, and it is intended to include all such changes and modifications as fall within the true scope of the invention.

Claims (14)

1. An article comprising a garment comprising a knitted fabric;

wherein the knit fabric comprises a fusible, elastic, solution-spun multi-component fiber, wherein the multi-component fiber has two or more regions of different composition that are continuous along the length of the fiber and comprises a cross-section, wherein at least a first region of the cross-section comprises an elastomeric polyurethane, polyurethaneurea, or mixture thereof, the cross-section comprises a second region comprising an elastomeric polyurethane, polyurethaneurea, or mixture thereof, and at least one fusibility improvement agent.

2. The article of claim 1, wherein the garment comprises a circular knit.

3. The article of claim 2, wherein the multicomponent fiber is present in each course, in alternating courses, or in a combination thereof.

4. The article of claim 2, wherein the multicomponent fibers are present in each course and comprise a jersey stitch construction.

5. The article of claim 2, wherein the multicomponent fibers are present in alternating courses and comprise a drop stitch or tuck stitch construction.

6. The article of claim 3 or 4, wherein the multicomponent fibers of different courses are in contact.

7. The article of claim 1, wherein the multicomponent fibers comprise uncoated fibers or coated fibers.

8. The article of claim 7, wherein the multicomponent fiber is coated with polyamide (nylon), cotton, polyester, or combinations thereof.

9. The article of claim 1 wherein the garment comprises a body underwear or hosiery.

10. The article of claim 1, wherein the fusibility improvement additive comprises at least one low temperature melting polyurethane.

11. The article of claim 10, wherein the low temperature melt polyurethane fusibility improvement agent has a melting point of 50 ℃ to 150 ℃.

12. The article of claim 10, wherein the low temperature melt polyurethane fusibility improvement agent has a melting point of less than 120 ℃.

13. The article of claim 1, wherein the second region is adjacent to or at least partially surrounds the first region, or wherein the first region is a core and the second region is a sheath.

14. The article of claim 1, wherein the first region comprises a polymer selected from the group consisting of (a) elastomeric polyurethanes having a high melting point of 190 ℃ to 250 ℃; (b) polyurethaneureas having a melting point greater than 240 ℃, and mixtures thereof.