BRPI0715552B1 - CUT-RESISTANT SLEEVE AND PROCESS FOR PRODUCING CUT-RESISTANT SLEEVE - Google Patents

Description

Field of the Invention The present invention relates to cut-resistant gloves with improved masking ability and methods of producing them.

Background of the Invention US Patent 5,925,149 to Pacific, et al., Discloses a fabric produced with dyed nylon fibers that have been treated with a stain blocker woven into a fabric with untreated nylon fibers followed by dyeing. of untreated nylon fibers in a second dyeing operation.

[003] US Patent Application Publication 2004/0235383 to Perry et al. Describes a yarn or fabric useful in protective clothing designed for activities where exposure to splashes of molten substances, radiant heat, or fire is likely to occur. The yarn or fabric is made from fire resistant fibers and fire resistant micro denier fibers. The weight ratio of fire resistant fibers to fire resistant micro denier fibers is in the range of 4-9: 2-6.

Publication of US Patent Application 2002/0106956 to Howland describes fabrics formed from intimate blends of high tenacity fibers and low tenacity fibers where low tenacity fibers are provided with a filament denier substantially below that of high tenacity fibers.

US Patent Application Publication US 2004/0025486 for Takiue describes a reinforcing composite yarn comprising a plurality of continuous filaments and in parallel with at least one substantially unwoven staple fiber yarn comprising a plurality of staple fibers. The staple fibers are preferably selected from nylon 6 staple fibers, nylon 66 staple fibers, meta-aromatic polyamide staple fibers, and p-aromatic polyamide staple fibers.

[006] Gloves made from p-aramid fibers have excellent cutting performance and have a high market price; however, p-aramid fibers naturally have a bright gold color that easily shows stains, giving an undesirable appearance after just one or a few uses. This affects the overall value of gloves in some cut resistance applications because they require more washing; In some cases the articles appear to be beyond their useful life when in fact they can still provide good shear strength shear strength. Any enhancement, therefore, in stain masking is desired especially if such enhancement can be combined with other enhancements that provide better comfort, durability, and / or a reduction in the amount of aramid fiber required for a particular level of cut resistance. .

Brief Description of the Invention The invention relates to a stain-resistant cut-off glove comprising (a) at least one aramid fiber, and (b) at least one fiber selected from the group consisting of polyamide fiber. aliphatic, polyolefin fiber, polyester fiber, acrylic fiber, and mixtures thereof; wherein up to and including 15 parts by weight of the total amount of fibers in the glove is provided with a dye or pigment such that they have a different color from the rest of the fibers; The dye or pigment is selected so that the colored fibers have a measured “L” value that is lower than the measured “L” value for the remaining fibers.

[008] The invention further relates to a process for producing a stain masking resistant glove comprising: a) mixing (i) at least one aramid fiber and (ii) at least one fiber selected from the group consisting of aliphatic polyamide fiber, polyolefin fiber, polyethylene fiber, acrylic fiber, and mixtures thereof; wherein up to and including 15 parts by weight of the total amount of fibers in the mixture are provided with a dye or pigment such that they have a different color from the rest of the fibers; the dye or pigment selected so that the colored fibers have a measured "L" value that is lower than the measured "L" value for the remaining fibers; (b) forming a spun yarn from the fiber blend; and (c) knit the glove from the spun strand.

Brief Description of the Figures Figure 1 is a representation of a possible knitted fabric of the type used in the glove of the present invention.

Figure 2 is a representation of a possible woven glove of the present invention.

Figure 3 is a representation of a section of staple fiber yarn comprising a possible intimate blend of fibers. Figure 4 is an illustration of a possible cross section of a staple beam useful in the gloves of the present invention. invention.

[0013] Figure 5 is an illustration of another possible cross section of a staple bundle useful in the gloves of the present invention.

[0014] Figure 6 is an illustration of another possible cross section of a staple wire bundle useful in the gloves of the present invention.

Fig. 7 is a cross-sectional illustration of a bundle of prior art discontinuous yarns commonly using 1.5 denier p-aramid fiber per filament (1.7 dtex per filament).

[0016] Figure 8 is an illustration of another possible cross section of a staple bundle useful in the gloves of the present invention.

Figure 9 is an illustration of a possible twisted yarn made from two single yarns.

[0018] Figure 10 is an illustration of a possible cross section of a twisted yarn made from two different single yarns.

[0019] Figure 11 is an illustration of a possible cross section of a twisted yarn made from two different single yarns.

[0020] Figure 12 is an illustration of a possible twisted yarn made from three different single yarns.

DETAILED DESCRIPTION OF THE INVENTION The p-aramid fiber, such as the Kevlar® brand p-aramid fiber offered by EI du Pont de Nemours and Company, Wilmington, DE, is desired in fabrics and articles including gloves by its superior. cut protection and many users look for the gold color of p-aramid yarn as evidence that the articles are cut resistant fiber. However, this gold color also easily shows stains giving the articles an undesirable appearance. Surprisingly, it has been observed that the addition of only a small amount of dyed or pigmented fiber can mask the appearance of blemishes and still allow some of the aramid fiber's natural gold color to appear.

In some embodiments the gloves of the present invention have even more benefits, including being provided with shear strength equivalent to or greater than the glove produced with commonly used 100% 1-p-aramid fiber yarns. 0.5 denier per filament (1.7 dtex per filament). In other words, in some embodiments the shear strength of a 100% p-aramid fiber fabric may be doubled by a fabric having smaller amounts of p-aramid fiber. In said embodiments, it is believed that a combination of different types of fibers, i.e., lubricating fiber, higher filament denier aramid fiber, lower filament denier aramid fiber, and colored fiber work together to provide not only masking of fibers. stains and cut resistance, but also improved abrasion resistance and fabric flexibility, which translates into improved durability and wearing comfort.

As used herein, the word "fabric" is intended to include any woven, knitted, or nonwoven layer structure or the like using yarn. By "yarn" is meant an assembly of spun or twisted fibers together to form a continuous filament. As used herein, a yarn generally refers to what is known in the art as a single yarn, which is a simpler filament of a suitable textile material for such operations as weaving and knitting. A spun staple yarn may be formed from staple staple fibers; A continuous multifilament yarn may be formed with or without twisting. When torsion is present, it all occurs in the same direction. As used herein the phrases "twisted yarn" and "bent yarn" may be used interchangeably and refer to two or more yarns, i.e. single yarns twisted or folded together. "Fabric" is intended to include any fabric produced by weaving; that is, interlacing or braiding of at least two wires typically at right angles. Generally said fabrics are produced by interweaving a yarn set, called warp yarns, with another yarn set, called weft or filler yarns. The woven fabric may be provided with essentially any interlacing such as simple interlacing, short fiber interlacing, basket interlacing, satin interlacing, twill interlacing, unbalanced interlacing, and the like. Simple interlacing is the most common. "Knitted" is intended to include a structure capable of being interlocked by a series of loops of one or more yarns by means of needles or yarns, such as warp knitting (e.g., knitting, Milanese, or Raschel) and weft knitting (eg circular or flat). "Nonwoven" is intended to include a fiber web forming a flexible sheet material capable of being produced without weaving or knitting and held together or by (i) mechanical interlocking of at least some of the fibers, (ii) fusion of at least some parts of some of the fibers, or (iii) bond at least some of the fibers using a bonding material. Nonwoven fabrics using yarns include mainly unidirectional fabrics, however other structures are possible.

In some preferred embodiments, the gloves of the present invention comprise a knitted fabric using any appropriate knitting pattern and conventional knitting machines. Figure 1 is a representation of a knitted fabric. Cut resistance and comfort are affected by the firmness of the knitting and said firmness can be adjusted to meet any specific need. A very effective combination of cut resistance and comfort has been observed, for example, in simple jersey knit and fuzz knit patterns. In some embodiments, the gloves of the present invention are provided with a weight base in the range of 3 to 30 oz / yd2 (100 to 1000 g / m2), preferably 5 to 25 oz / yd2 (170 to 850 g / m2), fabrics at the upper end of the weight base range providing more cut protection.

The gloves of the present invention may be used on articles to provide cut protection. Figure 2 is a representation of one of said gloves (1) having a detail (2) illustrating the knitted construction of the glove.

[0026] In one embodiment, the present invention relates to a stain masking resistant glove comprising at least one aramid fiber and at least one fiber selected from the group consisting of aliphatic polyamide fiber, polyolefin fiber, polyester fiber, acrylic fiber and mixtures thereof; wherein up to and including 15 parts by weight of the total amount of fibers in the glove is provided with a dye or pigment such that they are provided with a different color from the rest of the fibers; the dye or pigment selected so that the colored fibers are provided with a measured “L” value that is lower than the measured “L” value for the remaining fibers.

In some preferred embodiments, the gloves of the present invention comprise a stain masking resistant fabric comprising a yarn comprising an intimate blend of staple fibers, the blend comprising 20 to 50 parts by weight of the lubricating fiber, 20 to 40 parts by weight of a first aramid fiber having a linear density of 3.3 to 6 denier per filament (3.7 to 6.7 dtex per filament), 20 to 40 parts by weight of a second aramid fiber having a a linear density of 0.50 to 4.5 denier per filament (0.56 to 5.0 dtex per filament), and 2 to 15 parts by weight of a third aramid fiber having a linear density of 0.5 to 2.25 denier per filament (0.56 to 2.5 dtex per filament) based on the total weight of the first, second and third aramid lubricant fibers. The difference in linear filament density from the first aramid fiber to the second aramid fiber is 1 denier per filament (1.1 dtex per filament) or larger, and the third aramid fiber is provided with a different color from that of first or second aramid fibers. In some preferred embodiments, the lubricating fiber and the first and second aramid fibers are each individually present in amounts ranging from 26 to 40 parts by weight, based on 100 parts by weight of said fibers. In some preferred embodiments, the third aramid fiber is present in an amount of 3 to 12 parts by weight.

In some embodiments of the present invention, the difference in the linear filament density of the highest denier aramid fiber per filament and the lowest denier aramid fiber per filament is 1 denier per filament (1.1 dtex per filament) or bigger. In some preferred embodiments, the difference in linear filament density is 1.5 denier per filament (1.7 dtex per filament) or greater. The lubricating fiber is believed to reduce friction between fibers in the staple bundle, allowing the smaller filament denier aramid fiber and the larger filament denier aramid fiber to move more easily into the woven bundles of yarn. Figure 3 is a representation of a section of the staple fiber yarn (3) comprising a possible intimate blend of fibers.

Fig. 4 is a possible cross-sectional embodiment AA 'of the staple fiber yarn bundle of Fig. 3. Staple fiber yarn (4) contains a first aramid fiber (5) having a linear density at from 3.3 to 6 denier per filament (3.7 to 6.7 dtex per filament), and a second aramid fiber (6) having a linear density from 0.50 to 4.5 denier per filament (0.56 to 5.0 dtex per filament) and a third aramid fiber (7) provided with color and having a linear density of 0.5 to 2.25 denier per filament (0.56 to 2.5 dtex by filament). Lubricating fiber (8) has a linear density in the same range as the second aramid fiber (6). The lubricating fiber is evenly distributed in the yarn bundle and in many cases acts to separate the first and second aramid fibers. This is known to help prevent substantial interlocking of any aramid fibrils (not shown) that may be present or generated from wear on the surface of aramid fibers and also provide a lubricating effect on the yarn bundle filaments by providing fabric produced from said yarns having a greater characteristic of textile fiber and better aesthetic or "hand" feel.

Figure 5 illustrates another possible embodiment of a cross section AA 'of the staple fiber yarn bundle of Figure 3. Yarn bundle (11) is provided with the same first and second aramid fibers (5) and (6). 4, however, the third colored aramid fiber (9) has the same denier as the second aramid fiber and the lubricating fiber (10) has the same linear density in the same range as the first aramid fiber (5). ). Fig. 6 illustrates another possible embodiment of a cross section AA 'of the staple fiber yarn bundle of Fig. 3. The yarn bundle (12) is provided with the same first, second and third aramid fibers (5), (6) and (9) as Figure 5, however the lubricating fiber (14) is provided with the same linear density in the same range as the second aramid fiber (6). In comparison, Figure (7) is a cross-sectional illustration of the wire bundle of a commonly used prior art 1.5 denier per filament (1.7 dtex per filament) discontinuous p-aramid yarn (15) with 1.5 denier fibers per filament (1.7 dtex per filament) (16).

Figure 8 illustrates a possible embodiment of a cross section AA 'of the staple fiber yarn bundle of Figure 3. The yarn bundle (17) is provided with the same first and second aramid fibers (5) and ( 6) and fiber (10) selected from the group consisting of aliphatic polyamide fiber, polyolefin fiber, polyester fiber, acrylic fiber and mixtures thereof which is endowed with the same denier as the first aramid fiber (5) as However, present in this bundle of yarn is the colored fiber (18), which in said illustration is provided with the same linear density in the same range as either the first aramid fiber (5) or the fiber (10). The colored fiber 18 is provided with a dye or pigment and may be an aramid fiber, however, in some applications a dyed or pigmented lubricating fiber could be used. In some embodiments the dyed or pigmented fibers are provided with a lower filament denier than any of the dyed aramid fibers or other fibers. For simplicity of the figures, where the lubricating fiber is said to be basically of the same denier as an aramid type fiber, it is provided with the same diameter as that aramid type fiber. Actual fiber diameters may be relatively different depending on differences in polymer densities. Although in all said figures the individual fibers are represented as having a round cross-section, and that many of the fibers useful in said bundles preferably may have a round, oval or bean cross-sectional shape, it is understood that the fibers provided with other cross sections may be used in said bundles.

Although in the figures said fiber bundles represent single yarns, it is understood that said multi denier single yarns may be folded with one or more other single yarns to produce folded yarns. For example, Figure 9 is an illustration of one embodiment of a bent or bent yarn (19) produced from bending of two single wires together. Fig. 10 is a possible embodiment of a cross section BB 'of the bent yarn bundle of Fig. 9 containing two single yarns (20) made from an intimate blend of multi denier staple fibers as described above. 6 and a single wire (21) produced from only one type of filament (22).

Fig. 11 is another possible embodiment of a cross-section BB 'of the twisted yarn bundle of Fig. 9 containing two single yarns, with a single yarn (23) produced from an intimate blend of multi denier staple fibers as described previously in Figure 6, however without any colored fiber, and a single yarn (24) made from another fiber (25) and the colored fiber (26). As should be apparent from said figures, the small percentage of colored fiber in a bent yarn could be on any or all of the single yarns that make up the bent yarn.

Although two different single ones are shown in said figures, this is not restrictive and it should be understood that the bent yarn may contain more than two bent-twisted yarns together. For example, Figure 12 is an illustration of three single bent-twisted wires together. It should also be understood that the bent yarn can be made from two or more single yarns made from an intimate blend of multi denier staple fibers as described above, or the bent yarn can be made from at least one of the single yarns produced from an intimate blend of multi denier staple fibers and at least one yarn having any desired composition, including, for example, a yarn comprising continuous filament.

The color of fabrics and gloves can be measured using a spectrophotometer also called a colorimeter, which provides three value ranges "L", "a", and "b" that represent various color characteristics of the measured items. On the color scale, lower "L" values generally indicate a dark color, with white at about 100 and black at about 0. New or clean natural p-aramid fiber The dyed or non-dyed color is another bright color which when measured using a colorimeter has a value of "L" in the range of 80 to 90. In one embodiment, it has been observed that if up to and including 15 parts by weight of fibers in the glove are replaced with pigmented or dyed fibers so that the glove fabric has an “L” value of approximately 50 to 70 the glove is perceived to be less dirty and masks stains and still retains some hue of the golden aramid fiber. , indicating that the glove contains the desired cut resistant fiber. As fewer fibers are used or as the hue of the fibers is changed so that the glove fabric “L” value approximates that of the glove fabric containing only dyed or unpigmented fibers, the ability to Masking spots is reduced. Additionally, excessively dark shades with an “L” value of less than 50 are less desirable because the gloves completely lose their golden “signature” indicating the presence of aramid fibers.

In some embodiments, the cut-resistant gloves of the present invention comprise a yarn comprising an intimate blend of staple fibers. By intimate mixing is meant that the various staple fibers are homogeneously distributed in the staple fiber bundle. The staple fibers used in some embodiments of the present invention have a length of 2 to 20 cm. Staple fibers may be spun into yarns using short staple or cotton based yarns, long staple systems or wool based yarns, or expansion-break yarn systems. In some embodiments the cut length of staple fiber is preferably 3.5 to 6 cm, especially for staples to be used in cotton based spinning systems. In some other embodiments the cut length of staple fiber is preferably 3.5 to 16 cm, especially for staples to be used in long staple and wool based spinning systems. The staple fibers used in many embodiments of the present invention have a diameter of 5 to 30 pm and a linear density in the range of about 0.5 to 6.5 denier per filament (0.56 to 7.2 dtex per filament). ), preferably in the range 1.0 to 5.0 denier per filament (1.1 to 5.6 dtex per filament).

"Lubricating fiber" as used herein is intended to include any fiber which, when used with multi denier aramid fiber in the proportions designated herein to produce a yarn, increases the flexibility of fabrics or articles (including gloves) produced from said wire. The desired effect provided by the lubricating fiber is believed to be associated with the non-fibrillating and frictional properties of a polymer fiber. Therefore, in some preferred embodiments the lubricating fiber is a non-fibrillating or "fibril free" fiber. In some embodiments the lubricating fiber has a dynamic friction coefficient wire-to-wire when measured per se of less than 0.55, and in some embodiments the dynamic friction coefficient is less than 0.40 as measured by the ASTM Method. D3412 with capstan method at 50 grams load, 170 degrees winding angle, and 30 cm / sec relative movement. For example, when measured in this way, polyester polyester fiber has a measured dynamic friction coefficient of 0.50 and nylon nylon fiber has a measured dynamic friction coefficient of 0.36. The lubricating fiber need not be provided with any special surface finish or chemical treatment to provide lubricating behavior. Depending on the desired aesthetics of the final fabric and article, the lubricating fiber may be provided with a linear filament density equal to the linear filament density of one of the aramid-like fibers in the yarn or may be provided with a different linear filament density than the density. of linear filament of aramid fibers in the yarn.

In some preferred embodiments of the present invention, the lubricating fiber is selected from the group of aliphatic polyamide fiber, polyolefin fiber, polyester fiber, acrylic fiber and mixtures thereof. In some embodiments the lubricating fiber is a thermoplastic fiber. "Thermoplastic" is intended to have its definition of traditional polymer; that is, said materials flow in the manner of a viscous liquid when heated and solidify when cooled and thus occur reversibly from time to time in subsequent heating and cooling. In some more preferred embodiments the lubricating fiber is a melt-spun or gel-spun thermoplastic fiber.

In some preferred embodiments aliphatic polyamide fiber refers to any type of nylon polymer or copolymer-containing fiber. Nylons are long chain synthetic polyamides having recurrent amide groups (-NH-CO-) as an integral part of the polymer chain, and two common examples of nylon are nylon 66, which is polyhexamethylenediamine adipamide, and nylon 6, which is polycaprolactam. Other nylon may include nylon (11), which is produced from 11-amino undecanoic acid; and nylon 610, which is made from the condensation product of hexamethylenediamine and sebacic acid.

In some embodiments, polyolefin fiber refers to fiber produced from polypropylene or polyethylene fiber. Polypropylene is produced from propylene polymers or copolymers. A polypropylene fiber is commercially offered under the registered name of Phillips Fibers Marvess®. Polyethylene fiber is produced from ethylene polymers or copolymers of at least 50 mol% ethylene based on 100 mol% polymer and may be spun from a melt; however in some preferred embodiments the fibers are spun from a gel. Useful polyethylene fibers may be made from either high molecular weight polyethylene fiber or ultra high molecular weight polyethylene fiber. High molecular weight polyethylene fiber is generally provided with an average molecular weight basis greater than 40,000. A high molecular weight fused spun polyethylene fiber is commercially offered by Fibervisions®; Polyolefin fiber may also include a biocompatible fiber provided with various side-by-side or core sheath polyethylene and / or polypropylene fiber constructions. Commercially offered ultra-high molecular weight polyethylene fiber is generally provided with an average molecular weight basis of about one million or greater. An ultra-high molecular weight polyethylene or extended chain polyethylene fiber may generally be prepared as discussed in US 4,457,985. This type of gel-spun fiber is commercially offered under the registered names of Dyneema® offered by Toyobo and Spectra® offered by Honeywell.

In some embodiments, polyester fiber refers to any type of synthetic polymer or copolymer composed of at least 85% by weight of a dihydric alcohol ester and terephthalic acid. The polymer may be produced by the reaction of ethylene glycol and terephthalic acid or derivatives thereof. In some embodiments the preferred polyester is polyethylene terephthalate (PET) fiber. Polyester formulations may include a variety of comonomers, including diethylene glycol, cyclohexanedimethanol, poly (ethylene glycol), glutaric acid, azelaic acid, sebacic acid, isophthalic acid, and the like. In addition to said comonomers, branching agents such as trimesic acid, pyromellitic acid, trimethylolpropane and trimethylolethane, and pentaerythritol may be used. PET may be obtained by known polymerization techniques from either terephthalic acid or its lower alkyl esters (e.g. dimethyl terephthalate) and ethylene glycol or combinations or mixtures thereof. Useful polyesters may also include polyethylene naphthalate (PEN). PEN can be obtained by known polymerization techniques from 2,6-naphthalene dicarboxylic acid and ethylene glycol.

In some other embodiments the preferred polyesters are aromatic polyesters that exhibit thermotropic melting behavior. These include liquid crystalline or anisotropic fusion polyesters such as those offered under the registered name of Vectran® offered by Celanese. In some other embodiments aromatic fusion-processable liquid crystalline polyester polymers having low melting points are preferred, such as those described in US 5,525,700.

In some embodiments, acrylic fiber refers to fiber provided with at least 85% by weight of acrylonitrile units, an acrylonitrile unit being - (CH2-CHCN) -. The acrylic fiber may be made from acrylic polymers having 85 wt% or more of acrylonitrile of 15 wt% or less of an acrylonitrile copolymerizable ethylene monomer and mixtures of two or more of said acrylic polymers. Examples of the acylonitrile copolymerizable ethylene monomer include acylic acid, methacrylic acid and esters thereof (methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, etc.), vinyl acetate, vinyl chloride, vinylidene chloride, acrylamide, methacrylamide, methacrylonitrile, allylsulfonic acid, methanesulfonic acid and styrenesulfonic acid. Acrylic fibers of various types are commercially offered by Sterling Fibers, and an illustrative production method of acrylic polymers and fibers is described in US Patent 3,047,455.

In some embodiments of the present invention, the staple lubricating fibers have a shear index of at least 0.8 and preferably a shear index of 1.2 or greater. In some embodiments preferred staple lubricating fibers have a shear index of 1.5 or greater. The cut rate is the cut performance of a 475 grams / square meter (14 ounces / square yard) 100% woven or knitted fabric of a fiber to be tested which is then measured by ASTM F1790-97 (measured in grams , also known as Cut Protection Performance (CPP)) divided by the area density (in grams per square meter) of the tissue being cut.

In some embodiments of the present invention, preferred staple aramid fibers are p-aramid fibers. By p-aramid fibers is meant fibers made from p-aramid polymers; Poly (p-phenylene terephthalamide) (PPD-T) is the preferred p-aramid polymer. By PPD-T is meant the homopolymer resulting from the polymerization of p-phenylene diamine and terephthalyl chloride, and the resulting copolymers from the incorporation of small amounts of other diamines with p-phenylene diamine and p-phenylene diamine. small amounts of other diacid chlorides with terephthalyl chloride. As a general rule, other diamines and other diacid chlorides may be used in amounts up to about 10%% of a p-phenylene diamine or terephthaloyl chloride, or perhaps relatively larger, provided that only the other diamines and diacid chlorides have no groups. which interfere with the polymerization reaction. PPD-T also means copolymers resulting from the incorporation of other aromatic diamines and other aromatic diacid chlorides, such as, for example, 2,6-naphthaloyl chloride or chloro- or dichloroterephthaloyl chloride; provided that only if the other aromatic diamines and aromatic diacid chlorides are present in amounts which do not adversely affect the properties of p-aramid.

Additives may be used with p-aramid in the fibers and it has been observed that as much as 10% by weight of other polymeric material may be mixed with aramid or that copolymers may be used with as much as 10% of other polymeric material. diamine substituted by the diamine of one aramid or as much as 10% of another diacid chloride substituted by the aramid diacid chloride.

P-Aramid fibers are generally spun by extruding a solution of a p-aramid through a capillary into a coagulation bath. In the case of poly (p-phenylene terephthalamide), the solvent for the solution is generally concentrated sulfuric acid and the extrusion is generally through an air gap in a cold, aqueous coagulation bath. Said processes are well known and are generally described in US Patents 3,063,966; 3,767,756; 3,869,429, and 3,869,430. P-Aramid fibers are commercially offered as Kevlar® brand fibers, which are offered by E. I. du Pont de Nemours and Company, and Twaron® brand fibers, which are offered by Teijin, Ltd.

Any of the fibers discussed herein or other fibers that are useful in the present invention may be provided with color using conventional techniques well known in the art which are used to dye or dye said fibers. Alternatively, many colored fibers can be obtained commercially from various vendors. A representative method of producing colored aramid fibers is described in US Patents 5,114,652 and US 4,994,323.

In some embodiments, the present invention relates to processes for producing a cut resistant and stain masking glove comprising the steps of blending at least one aramid fiber and at least one fiber selected from the group consisting of aliphatic polyamide fiber, polyolefin fiber, polyester fiber, acrylic fiber, and mixtures thereof, where up to and including 15 parts by weight of the total amount of fiber in the mixture is provided with a dye or pigment such that they are endowed with a different color from the rest of the fibers, the dye or pigment is selected so that the colored fibers have a measured “L” value which is lower than the measured “L” value for the remaining fibers; forming a discontinuous spun yarn from the fiber blend; and knit the glove from the spun strand.

In some preferred embodiments, the intimate staple fiber blend is produced by first mixing together staple fibers obtained from open bales, together with any other staple fibers, if desired for additional functionality. The fiber blend is then formed into a belt using a carding machine. A carding machine is commonly used in the fiber industry to separate, align, and send fibers in a continuous filament of loosely assembled fibers without substantial twisting, commonly known as a carded belt. The carded belt is processed into a stretched belt, typically by, but not limited to, a two-step stretching process.

Spun discontinuous strands are then formed from the stretched belt using conventional techniques. Said techniques include conventional cotton system short-discontinuous spinning processes, such as, for example, open end spinning, ring spinning, or higher airspeed spinning, techniques such as Murata air jet spinning where air is used for twisting the staple fibers in a wire. The formation of the spun yarns useful in the gloves of the present invention may also be achieved by the use of conventional wool system, stretch-break and long-discontinuous spinning processes such as, for example, ring spinning of woolen fabric or wool semi-fabric. Irrespective of the processing system, ring spinning is the generally preferred method for producing cut resistant staple yarns.

Blending staple fibers prior to carding is a preferred method for producing well-blended, homogeneous, intimate blend spun yarns used in the present invention, however, other processes are possible. For example, the intimate fiber blend may be produced by blend cutting processes; that is, the various stretched fibers or continuous filament form may be blended together during or prior to crimping or discontinuous cutting. This method may be useful when aramid staple fiber is obtained from multi-denier spun stretch or multi-denier continuous multifilament yarn. For example, a continuous multifilament aramid yarn may be spun from the solution through a spinner specially prepared to create a yarn where the individual aramid filaments are provided with two or more different linear densities; The yarn can then be cut into discontinuous sections to produce a mixture of multi denier aramid discontinuous sections. The lubricating and colored fibers may be combined with said multi denier discontinuous aramid mixture either by combining the lubricating and colored fibers with the aramid fiber and cutting them together, or by mixing the colored and lubricating discontinuous fibers with the aramid fiber. discontinuous aramid after cutting. Another method of blending the fibers is by carding and / or stretching belt mixing; that is, to produce individual straps of various staple fibers in the blend, or combinations of various staple fibers in the blend, and to provide said individual cardboards and / or stranded strands for strand and / or staple spinning devices designed to blend the fibers. strap while spinning the staple wire. All of these methods are not intended to be limited and other methods of blending staple fibers and yarn production are possible. All such discontinuous yarns may contain other fibers as long as the desired fabric attributes are not dramatically compromised.

The spun yarn of an intimate blend of fibers is then preferably fed to a knitting device to produce a knitted glove. Said knitting devices include a range of knitting machines from standard to very thin gauges, such as the Sheima Seiki glove knitting machine used in the following examples. If desired, multiple ends or yarns may be provided for the knitting machine; that is, a bundle of yarn or a bundle of folded yarn can be co-fed in the knitting machine and knitted in a glove using conventional techniques. In some embodiments, it is desirable to add functionality to the gloves by co-feeding one or more other staple or continuous filament yarns with one or more spun yarn provided with the intimate blend of fibers. Knitting grip can be adjusted to meet any specific needs. A very effective combination of cut resistance and comfort has been observed, for example, in simple jersey knitting and Terry knitting patterns. Test Methods [0054] Color Measurement. The system used for color measurement is the 1976 CIELAB color scale (L-a-b system developed by the Commission Internationale de l'Eclairage). In the CIE "L-a-b" system, color is seen as a three-dimensional point in space. The value “L” is the brightness coordinate with high values being the brightest, the value “a” is the red / green coordinate with "+ a" indicating the red color and "-a" indicating the green color and the value "b" is the yellow / blue coordinate with "+ b" indicating the yellow tint and "-b" indicating the blue tint. Spectrophotometers were used to measure color for glove fabrics produced from sample yarn items. The GretagMacbeth Color-Eye 3100 spectrophotometer was used to measure some of the glove tissues produced from the sample yarn items in Table 2. The Hunter Lab UltraScan® PRO spectrophotometer was used to measure some of the glove tissues produced from the glove items. sample wire and gloves used and washed in Tables 2 and 4. The Datacolor 400TM spectrophotometer was used to measure some of the glove tissues produced from the wire sample items in Table 3. All three spectrophotometers used the industry standard. 10-degree observer and D65 illuminant.

Examples In the following examples, the gloves were knitted using staple fiber-based ring spun yarns. Staple fiber blend compositions were prepared by mixing various staple fibers of a type shown in Table 1 in proportions as shown in Table 2. In all cases aramid fiber was produced from poly (paraphenylene terephthalamide) (PPD). -T). This type of fiber is known by the Kevlar® trademark and was manufactured by E.l. du Pont de Nemours and Company and is endowed with L / a / b color values of approximately 85 / -5.9 / 45. The lubricant fiber component was semi-opaque nylon 66 fiber sold by Invista under the Type 420 designation and has L / a / b color values of approximately 91 / -0.65 / 0.42. Aramid colored fibers were produced colored using spun pigments. Royal Blue colored Kevlai® brand fiber has L / a / b color values of approximately 25 / -5.2 / -18. The producer of black colored acrylic fiber was manufactured by GYDSA; said black fiber had a color similar to the Kevlar® brand colored black fiber, which has L / a / b color values of 19 / -1.9 / -27. Table 1_______________________________________________ [0056] The yarns used to produce knitted glove fabrics were produced as follows. For control wire A, approximately seven pounds of a single type of PPD-T staple fiber was fed directly into a carding machine to produce the carded strap. Two to nine kilograms of each staple fiber blend composition for strands 1 to 5 and comparison strands B to D as shown in Table 2 were then produced. Said staple fiber blends were produced by first hand blending the fibers and then feeding the blend twice through a harvester to produce uniform fiber blends. Yarn 6 was produced by combining three types of continuous aramid filaments in amounts adequate to produce about 700 kilograms of one of coiled cord. The crimped handle was then cut into staple fibers about 4.8 inches long to form an intimate blend of three types of aramid fibers. Two gears by weight of the intimate blend of three aramid staple fibers were then mixed staple with a nylon 66 fiber portion to form a final staple fiber blend. Each fiber blend for strands 1 through 6 and A through D was then fed through a standard carding machine to produce the carded belt.

The carded strap was then stretched using two-pass stretch (tear / finish stretch) on a stretched strap and processed into a wick frame. 6560 dtex strands (0.9 count) were produced for each of items 1 to 5 and A to D. A 7380 dtex strands (0.8 skew) were produced for item 6. Yarns were then Yarn was produced by double-ended ring spinning of each wick for compositions 1 to 5 and A to D. Yarn was produced by one-end ring spinning of each wick for composition 6. Counting cotton yarn 10/1 s were produced with a 3.10 twisting multiplier for items 1 to 5 and A to D. A 16.5s count cotton yarn was produced with a 3.10 twisting multiplier for item 6. Each The final yarns 1 through 5 and A through D were produced by bending a pair of 10 / 1s yarns together with an equilibrium reverse twist to produce 10 / 2s yarns. The final yarn item 6 was produced by bending a pair of 16.5 / ls yarns together with an inverse equilibrium twist to produce 16.5 / 2s yarns.

The 10 / 2s cc and 16.5 / 2s cc yarns were knitted in glove fabric samples using the standard 7 gauge Sheima Seiki glove knitting machine. The knitting machine time has been adjusted to produce glove bodies about one meter long to provide fabric samples suitable for subsequent cut testing. Fabric samples for items 1 through 5 and A to D were produced by feeding 3 / 10s of 2 / 2s to the glove knitting machine to produce glove fabric samples with a weight basis of about 20 oz / yd 2 (680 g / m2). The glove fabric for item 6 was produced by feeding 4 ends of 16.5 / 2s to the knitting machine to produce fabric samples of about 16 oz / yd2 (542 g / m2). Standard size gloves were then produced from each of the threads having the same nominal weight basis as the fabrics. The tissues were subjected to color testing and the results are presented below in Table 3.

A random sample of 10 washed 100% aramid fiber gloves that were worn by industrial workers who manipulated sheet metal and were designated "AA" through "BB" were tested for color and the results are presented. These gloves were darker than the new 100% aramid fiber glove (designated "A" in the table) and had varying degrees of stains that were not removed by washing.

By comparing the color test results of the washed and dyed gloves AA to BB in Table 4 with the color test results of items 1 to 6 of Table 3, it is evident that by adding a small amount of fiber colored, the visual difference between a new glove and a used glove is considerably reduced. Gloves produced from the compositions of B to D of Table 3 are less desired because they are even darker in color and do not allow much of the golden yellow base to appear. ___________________________Table 4___________________________ Claims

Claims (11)

1. Spot-masking CUT-RESISTANT GLOVE (1), characterized in that it comprises: (a) at least one dyed or pigmented aramid fiber (7, 9, 18}, (b) at least one aramid fiber (5) natural or dyed color, and (c) at least one fiber (8, 10, 14) selected from the group consisting of aliphatic polyamide fiber, polyolefin fiber, polyester fiber, acrylic fiber and blends wherein up to and including 15 parts by weight of the total amount of fibers in the glove are provided with a dye or pigment such that they have a different color from the rest of the fibers, the dye or pigment is selected such that Colored fibers have a measured “L” value that is lower than the measured “L” value for the remaining fibers. GLOVE according to claim 1, characterized in that it has an L value of 50 to 70 units. GLOVE according to claim 1, characterized in that it has an L value of 52 to 68 units. GLOVE according to claim 1, characterized in that the colored fibers and the remaining fibers are present as an intimate mixture of discontinuous fibers. GLOVE according to claim 1, characterized in that the colored fibers are present in the first yarn and the remaining fibers are present in one or more additional yarns. GLOVE according to claim 1, characterized in that the aramid fiber is poly (paraphenylene terephthalamide) fiber. A process for producing a spot-masking-resistant glove (1) as defined in claim 1, comprising: (a) mixing (i) at least one dyed or pigmented aramid fiber (7) , 9, 18), (ii) at least one natural or dyed aramid fiber (5), and (iii) at least one fiber (8,10,14) selected from the group consisting of aliphatic polyamide, polyolefin fiber, polyester fiber, acrylic fiber and mixtures thereof; wherein up to and including 15 parts by weight of the total amount of fibers in the mixture are provided with a dye or pigment such that they have a different color from the rest of the fibers; the dye or pigment selected so that the colored fibers have a measured “L” value that is lower than the measured “L” value for the remaining fibers; (b) forming a spun batch (3, 4, 11, 12, 17) from the fiber blend; and (c) knitting the glove (1) from the spun strand (3, 4, 11,12, 17). Process according to claim 7, characterized in that the blending is implemented at least in part by blending the fibers together and carding the fibers to form a belt containing an intimate blend of discontinuous fiber. Process according to Claim 7, characterized in that the mixing is implemented immediately before or during the formation of a spun batch (3, 4, 11, 12, 17) by providing one or more straps each. one of which substantially contains only a fiber of (i) or (ii) a staple wire spinning device. Process according to Claim 7, characterized in that the spun discontinuous yarn (3, 4, 11, 12, 17) is formed using ring spinning. Process according to Claim 7, characterized in that the first, second or third aramid fibers comprise poly (paraphenylene terephthalamide).