JP2003286663A - Artificial leather - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a raised artificial leather having soft touch feeling, particularly excellent in lighting effect. <P>SOLUTION: This artificial leather is composed of a fiber entangling body containing an ultrafine fiber containing single fiber with &le;1.1 dtex fineness and a polymer elastomer and has a raised surface. In the artificial leather, the ultrafine fiber is a latent crimp-developing polyester conjugate fiber obtained by mutually conjugating two kinds of polytrimethylene terephthalates having 0.05-0.40 (dl/g) difference of intrinsic viscosity in side-by-side type. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brushed artificial leather having a soft feel and, in particular, an excellent lighting effect. 2. Description of the Related Art The present applicant has previously described Japanese Patent Application Laid-Open No. 11-222.
No. 780 proposes that by using polytrimethylene terephthalate ultrafine fibers for the non-woven fabric constituting the artificial leather, it is possible to obtain a brushed artificial leather having a soft texture and excellent surface brushing quality such as a lighting effect. However, there is a further need for brushed artificial leather whose lighting effect is very similar to natural suede. [0003] The present invention is to provide an artificial leather having a soft texture and, in particular, a lighting effect very similar to a natural suede. Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, the present invention has been achieved by using a specific fiber as an ultrafine fiber constituting a fiber entangled body. And completed the present invention. That is, the present invention is constituted by a fiber entangled body containing ultrafine fibers having a single fiber fineness of 1.1 dtex or less and a polymer elastic body,
In addition, the surface is artificial leather whose surface is raised, and the ultrafine fibers are composed of two types of polytrimethylene terephthalate having an intrinsic viscosity difference of 0.05 to 0.40 (dl / g) in a side-by-side type. An artificial leather characterized by a latent crimp developing polyester composite fiber. [0005] According to the present invention, a brushed artificial leather having a soft texture and particularly excellent in lighting effect can be obtained. Latent crimp-expressing polyester composite fiber of the present invention,
A crimp is developed by the heat treatment. The composite ratio of the two types of polytrimethylene terephthalate used in the composite fiber is expressed in mass%, preferably 70/30 to 30/7.
0, more preferably in the range of 60/40 to 40/60, and the joint surface shape (there is a straight or curved shape) of the two components in the fiber cross section is not limited. The difference in intrinsic viscosity between the two types of polytrimethylene terephthalate constituting the latently crimp-expressing polyester fiber of the present invention must be 0.05 to 0.40 (dl / g), preferably 0. .10 to 0.35 (dl /
g), more preferably 0.15 to 0.35 (dl / g)
It is. For example, the intrinsic viscosity on the high viscosity side is set to 0.70 to 1.
When it is selected from 30 (dl / g), the intrinsic viscosity on the low viscosity side is preferably selected from 0.50 to 1.10 (dl / g). The intrinsic viscosity on the low viscosity side is 0.80 (dl /
g) or more is preferable, and 0.85 to 1.00 (dl / g)
Is more preferable, and 0.90 to 1.00 (dl / g) is most preferable. If the intrinsic viscosity difference is less than 0.05, the object of the present invention cannot be achieved, and if it exceeds 0.40 (dl / g),
It becomes inferior in melt spinnability. The intrinsic viscosity of the composite fiber itself, that is,
The average intrinsic viscosity is preferably 0.70 to 1.20 (dl / g), more preferably 0.80 to 1.20 (dl / g), and most preferably 0.85 to 1.15 (dl / g). Preferably
0.90 to 1.10 (dl / g) is more preferable. In addition, the value of the intrinsic viscosity referred to in the present invention is not the polymer used but the viscosity of the spun yarn. The reason for this is
The disadvantages of polytrimethylene terephthalate are that it tends to be thermally decomposed compared to polyethylene terephthalate, etc., and even if a polymer with a high intrinsic viscosity is used, the intrinsic viscosity is significantly reduced by thermal decomposition. This is because it is difficult to maintain a large difference in viscosity. [0008] Polytrimethylene terephthalate is a polyester having trimethylene terephthalate unit as a main repeating unit. The trimethylene terephthalate unit contains at least 50 mol%, preferably at least 70 mol%, more preferably at least 80 mol%, most preferably. Is 90 mol%
Including the above. Therefore, as the third component, the total amount of the other acid component and / or glycol component is 50 mol% or less, preferably 30 mol% or less, more preferably 20 mol% or less, and most preferably 10 mol% or less. Polytrimethylene terephthalate contained. [0009] Polytrimethylene terephthalate is synthesized by combining terephthalic acid or a functional derivative thereof with trimethylene glycol or a functional derivative thereof in the presence of a catalyst under appropriate reaction conditions. In this synthesis process, one or more suitable third components may be added to form a copolymerized polyester, or a polyester other than polytrimethylene terephthalate such as polyethylene terephthalate and polybutylene terephthalate, or a polyester such as nylon, After separately synthesizing methylene terephthalate, both may be blended. When blended, the ratio of polytrimethylene terephthalate is preferably 70/30 to 30/70, more preferably 60/40 to 40/60 by mass%. The third components to be added include aliphatic dicarboxylic acids (oxalic acid, adipic acid, etc.), alicyclic dicarboxylic acids (cyclohexane dicarboxylic acid, etc.), aromatic dicarboxylic acids (isophthalic acid, sodium sulfoisophthalic acid, etc.). ), Aliphatic glycols (ethylene glycol, 1,2
-Propylene glycol, tetramethylene glycol, etc.), alicyclic glycol (cyclohexane dimethanol, etc.), aliphatic glycol containing aromatics (1,4-bis (β-hydroxyethoxy) benzene, etc.), polyether glycol (polyethylene glycol) , Polypropylene glycol and the like), aliphatic oxycarboxylic acids (ω-oxycaproic acid and the like), aromatic oxycarboxylic acids (P-oxybenzoic acid and the like) and the like. Compounds having one or more ester-forming functional groups (such as benzoic acid or glycerin) can also be used as long as the polymer is substantially linear. Further, matting agents such as titanium dioxide, stabilizers such as phosphoric acid, ultraviolet absorbers such as hydroxybenzophenone derivatives, crystallization nucleating agents such as talc, lubricating agents such as aerosil, and antioxidants such as hindered phenol derivatives. Agents, flame retardants, antistatic agents, pigments, optical brighteners, infrared absorbers, defoamers, and the like. The shape of the fiber may be uniform in the length direction or thick and thin, and the cross-sectional shape is round, triangular, L-shaped, T-shaped, Y-shaped, W-shaped, Yatsuha-shaped, flat (flatness). 1.3 to 4 types, including W type, I type, Boomerang type, corrugated type, skewered dumpling type, cocoon type, rectangular solid type, etc.), polygon type such as dog bone type, etc., and multi-leaf type It may be a hollow type or an irregular type. The monofilament fineness of the latently crimp-expressing polyester fiber used in the present invention is 1.1 dtex or less, preferably 0.01 to 0.6 dtex, more preferably 0.0 dtex.
It is 1 to 0.4 dtex, and if it exceeds 1.1 dtex, the object of the present invention is not achieved. In the present invention,
Most preferably, the fiber entangled body is formed using 100% of such ultrafine fibers, but if necessary, 50% by mass may be used.
Or less, preferably 30% by mass or less, more preferably 10% by mass or less.
Within the range of mass% or less, other fibers such as natural fibers and synthetic fibers, for example, natural fibers such as cotton, wool, hemp, silk, cupra rayon, viscose rayon, polynosic rayon, purified cellulose fiber, acetate fiber, Polyester fibers such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate,
Various man-made fibers such as nylon (aliphatic nylon such as nylon 6 and 66) fibers, acrylic fibers, polyolefin (polyethylene and polypropylene etc.) fibers, polyurethane fibers, and fibers made of copolymers thereof, and homo- or hetero-polymers A fiber entangled body may be formed by mixing conjugate fibers (side-by-side type, eccentric sheath-core type, etc.) using the same. In order to form a fiber entangled body, an ultrafine web is formed by carding or papermaking according to a conventional method, or the ultrafine web obtained by direct spinning is subjected to needle punching, water jetting, or the like. A fiber entangled body is formed by a punch or a combination thereof. More preferably, after forming an ultrafine web using a card method or a papermaking method, laminating on a woven or knitted fabric, or laminating an ultrafine web obtained by a direct spinning method on a woven or knitted fabric, needle punching, water jet punching Alternatively, a structure in which the fibers constituting the ultrafine web and the woven or knitted fabric are entangled and integrated by a combination thereof is preferable. At this time, there is a method of laminating and knitting the woven or knitted material on both sides or one side of the ultrafine web, a method of stacking a plurality of the tangled and entangled again, slicing in a later step, and taking two pieces. . In order to cause the latently crimp-expressing polyester fiber to exhibit crimp, it is necessary to perform a heat treatment.
The heat treatment is preferably performed after web preparation or after forming the fiber entangled body. In particular, by performing heat treatment in a state where the thickness is regulated, a dense fiber entangled body having a desired density can be obtained. The heat treatment can be performed using a heat treatment device such as a hot air circulation dryer, a hot air once-through dryer, a suction drum dryer, a heat roll such as a flat calender roll, and an emboss roll. In the present invention, when the fibers constituting the ultrafine web and the woven / knitted fabric are entangled and integrated, the fiber material used for the woven / knitted fabric is not limited, and any natural fiber, chemical fiber,
Synthetic fibers and the like are used. Examples of such fibers include natural fibers such as cotton, wool, hemp, and silk, cupra rayon, viscose rayon, polynosic rayon, purified cellulose fiber, acetate fiber, polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, and the like. Various man-made fibers such as polyester fiber, nylon (aliphatic nylon such as nylon 6 or 66) fiber, acrylic fiber, polyolefin (polyethylene or polypropylene) fiber, polyurethane fiber and the like, and fibers made of these copolymers and the like. Known synthetic fibers such as composite fibers using different polymers (side-by-side type, eccentric sheath-core type, etc.) can be used. Particularly, latent crimp-expressing polyester fibers containing at least polytrimethylene terephthalate as one component are preferable. preferable. The latently-crimpable polyester fiber containing at least polytrimethylene terephthalate as one component used in the woven or knitted fabric is composed of at least two kinds of polyester components (specifically, a side-by-side type or an eccentric core-sheath type). And at least one component thereof is polytrimethylene terephthalate, which develops crimp by heat treatment. When composed of two types of polyester components, the composite ratio of the two components (generally, in many cases in the range of 70/30 to 30/70 by mass%), the joint surface shape of the two components in the fiber cross section (There is a straight or curved shape) is not limited. The total fineness of the latent crimp developing polyester fiber used for the woven or knitted fabric is preferably 20 to 300 dtex, and the single yarn fineness is preferably 0.5 to 20 dtex, but is not limited thereto. Specifically, Japanese Patent Application Laid-Open No. 2001-2001
Japanese Patent Application Laid-Open No.-40537 discloses a method using polytrimethylene terephthalate as one component. That is, it is a conjugate fiber in which two kinds of polyester polymers are joined in a side-by-side type or an eccentric core-sheath type. In the case of a side-by-side type, the melt viscosity ratio of the two polyesters is preferably 1.00 to 2.00, and in the case of an eccentric core-sheath type,
It is preferable that the sheath polymer is faster than the sheath polymer by 3 times or more in the alkali weight loss rate ratio between the sheath polymer and the core polymer. Specific combinations of polymers include polytrimethylene terephthalate and polyethylene terephthalate (a polyester having terephthalic acid as a main dicarboxylic acid and ethylene glycol as a main glycol component, glycols such as butanediol, isophthalic acid, and 2.6). A dicarboxylic acid such as naphthalenedicarboxylic acid, etc., and may contain additives such as other polymers, matting agents, flame retardants, antistatic agents, pigments, etc.) and poly. Trimethylene terephthalate and polybutylene terephthalate (where terephthalic acid is the main dicarboxylic acid and
It is a polyester containing 4-butanediol as a main glycol component, and may be copolymerized with glycols such as ethylene glycol or dicarboxylic acids such as isophthalic acid and 2.6-naphthalenedicarboxylic acid. It may contain additives such as other polymers, matting agents, flame retardants, antistatic agents, pigments and the like. ) Is preferable, and in particular, one in which polytrimethylene terephthalate is arranged inside the crimp is preferable. In addition to the above-mentioned JP-A-2001-40537, JP-B-43-19108, JP-A-11-1
JP-A-89923, JP-A-2000-239927, JP-A-2000-256918, JP-A-2000
JP-A-328382 and JP-A-2001-81640 disclose that the first component is polytrimethylene terephthalate, and the second component is different from the first component, such as polytrimethylene terephthalate, polyethylene terephthalate, and polybutylene terephthalate. Side-by-side type or eccentric sheath-core type composite fibers in which polyesters are arranged in parallel or eccentrically. In particular, a combination of polytrimethylene terephthalate and copolymerized polytrimethylene terephthalate and a combination of two kinds of polytrimethylene terephthalate having different intrinsic viscosities are preferable. In the woven or knitted fabric, a latent crimp-expressing polyester composite fiber and another fiber such as natural fiber, synthetic fiber or the like, for example, cotton, wool, hemp, silk, etc., usually in an amount of 50% by mass or less. Natural fiber, cupra rayon, viscose rayon, polynosic rayon, purified cellulose fiber, acetate fiber, polyester fiber such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, and nylon (aliphatic nylon such as nylon 6 and 66) Various artificial fibers such as fibers, acrylic fibers, polyolefin (polyethylene and polypropylene) fibers, polyurethane fibers, and the like, fibers composed of these copolymers, and composite fibers using the same or different polymers (side-by-side type, eccentric sheath core) Knitted fabric) The fiber material constituting the woven or knitted fabric is preferably made to have a twist coefficient (K) represented by the following formula, preferably from 3000 to 3200.
When twisted so as to be 0, more preferably 7000 to 25000, and most preferably 7000 to 23000, the effect of imparting stretchability to artificial leather is more effective. Twist coefficient (K) = T × D ^0.5 (where T: twist number (T / m), D: fiber fineness (dte
x)) In producing a knitted woven fabric using a latently crimp-expressing polyester fiber, for example, in the case of a woven fabric, it is preferable to use both a warp and a weft because excellent stretchability can be obtained in both the weft and the weft, but if necessary, You may use it for either a warp or a weft. In that case, excellent stretchability can be obtained only in the used direction. As the woven structure, taffeta, twill, satin and its modified structure can be used.
７０70 / 2.54 cm is preferred. The knitted structure may be a weft knit (round knit, flat knit) or warp knit (tricot, Russell), and the gauge is preferably 22 to 36 gauge. The entangled form of the fiber entangled body of the present invention may be such that the knitted fabric and the ultrafine fibers may be intertwined with each other three-dimensionally, or the fiber bundles in which the ultrafine fibers are gathered may be intertwined with each other three-dimensionally. The fibers and the fiber bundles may be mixed and intertwined. The artificial leather of the present invention is manufactured by impregnating the inside of the above-mentioned fiber entangled body with a polymer elastic body and then raising the fiber. Prior to applying the polymer elastic body, shrinkage heat treatment, heat press, wet press, etc. are performed to increase the density of the base fabric for artificial leather (also serves as heat treatment for the appearance of crimp of latently crimp-expressing polyester fiber). Or a step of fixing the form with a paste such as polyvinyl alcohol. As the polymer elastic body, a polyurethane elastic body, an acrylonitrile-butadiene elastic body, a styrene-butadiene elastic body, a synthetic rubber such as polybutadiene or neoprene, a polyacrylate, or the like is used.
If necessary, additives such as a coloring agent such as carbon black, an antioxidant, an antistatic agent, a dispersant, a softener, and a coagulation regulator may be blended into the elastic polymer. The preferred impregnation rate of the polymer elastic body to the fiber entangled body is 20 to 75% by mass, and in the case of the fiber entangled body with the knitted fabric, it is preferably 3 to 20% by mass, and 4 to 20% by mass. More preferably, it is most preferably 5 to 15% by mass. As an example of a method of impregnating a polymer elastic body, a polyurethane elastic body is exemplified. A method of impregnating a fiber-entangled body with an emulsion of a water-dispersed polyurethane elastic body and drying the same, and a solution-type polyurethane elastic body dissolved in a solvent such as DMF. Impregnated,
There are methods such as solidification by a dry method and a wet method. Next, if necessary, before dyeing, the fibers are reduced in alkali by about 3 to 30% by mass, and post-processing such as dyeing and anti-static water-repellent treatment is performed to obtain artificial leather. Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. The measurement method and evaluation method used in the present invention are as follows. (1) Intrinsic viscosity Intrinsic viscosity [η] (dl / g) is a value obtained based on the definition of the following equation. In the definition, ηr is obtained by dividing the viscosity at 35 ° C. of a diluted solution of a polytrimethylene terephthalate yarn or a polyethylene terephthalate yarn dissolved in an o-chlorophenol solvent having a purity of 98% or more by the viscosity of the solvent measured at the same temperature. And is defined as the relative viscosity. C
Is the polymer concentration in g / 100 ml. In the case of composite multifilaments using polymers having different intrinsic viscosities, it is difficult to measure the respective intrinsic viscosities of the multifilaments.
Each type of polymer is spun alone, and the intrinsic viscosity measured using the obtained yarn is defined as the intrinsic viscosity of the composite multifilament. (2) Evaluation of Lighting Effect The natural deerskin suede is evaluated as 10 and evaluated according to a 10-step method. Those having a lighting effect comparable to natural deerskin suede were evaluated as 10, and those having no lighting effect were evaluated as 0. In this example, the evaluation was made by 10 processing engineers. Average is 9 or more; ◎ Average is 7 to 8; ○ Average is 4 to 6; △ Average is 3 or less; × (3) The stretchable artificial leather is pulled, and the elongation recovery rate of the artificial leather is 90%.
The elongation is evaluated as described above. 15% or more in both directions of process; ○ 10% or more in both directions of process; Δ Less than 10% in both directions of process; × [Example 1] Two kinds of polytrimethylene terephthalates having different intrinsic viscosities were used in a mass ratio. Extruded from a spinneret for spinning side-by-side conjugate fiber at a ratio of 1: 1 and a spinning temperature of 26.
An undrawn yarn was obtained at 5 ° C. and a spinning speed of 1300 m / min. Next, the film is stretched at a stretch ratio of 2.5 times to obtain 39 dtex / 350.
As a result, a side-by-side type composite multifilament (f) was obtained. The intrinsic viscosity of the obtained composite multifilament was 0.90 on the high viscosity side and 0.70 on the low viscosity side. On the other hand, in the same manner as described above, 56 dtex /
A side-by-side composite multifilament of 12f was obtained. The intrinsic viscosity of the obtained composite multifilament is
The high viscosity side was 0.88 and the low viscosity side was 0.70. A twist (800 T / m) of this composite filament is used for warp and weft, and the density is 55 / 2.5
A 4 cm taffeta with a basis weight of 80 g / m ² was prepared. After cutting the previously manufactured 39 dtex / 350f side-by-side type composite multifilament (extremely fine fiber) to a length of 5 mm, it was dispersed in water to prepare a papermaking slurry for the surface layer and the back layer. The basis weight of the surface layer was 100 g / m ² , and the basis weight of the back layer was 50.
g / m ² , the above-mentioned taffeta was inserted to form a laminated fiber sheet, and then the fibers constituting the papermaking sheet were three-dimensionally entangled by high-speed water jet to obtain a nonwoven fabric. The high-speed water flow was measured at 3920 kPa from the surface layer and 294 kPa from the back layer using a straight flow jet nozzle with a hole diameter of 0.15 mmΦ.
After jetting at a pressure of 0 kPa and performing the confounding process, a wire mesh of 60 mesh is inserted between the sheet and the nozzle, and the water pressure is 245.
After jetting a water stream at 0 kPa, dry with a pin tenter,
A nonwoven sheet having a basis weight of 200 g / m ² and a thickness of 0.8 mm was produced. After the surface of the sheet was brushed with # 400 emery paper, a 7% concentration of Evaphanol (registered trademark) AP-12 (manufactured by Nika Chemical Co., Ltd., without forced emulsification type nonionic polyether) was used. To an emulsion of a yellowing type polyurethane elastic body), sodium sulfate was added as a heat-sensitive coagulant to prepare an impregnating liquid. The impregnating liquid was impregnated with a nonwoven sheet material, and squeezed with a mangle so that the impregnation rate was 160%. Subsequently, it was dried at 130 ° C. for 3 minutes with a pin tenter to produce a raw material for artificial leather, which was dyed with a jet dyeing machine. The writing effect of the obtained brushed artificial leather was ◎, and the stretchability was ○. COMPARATIVE EXAMPLE 1 A composite filament having an intrinsic viscosity of 1.40 on the high-viscosity side and 0.72 on the low-viscosity side was prepared as the ultrafine fiber of Example 1. In this case, yarn bending was remarkable, and yarn breakage occurred frequently, so that stable production was not possible. COMPARATIVE EXAMPLE 2 The ultrafine fiber of Example 1 had an intrinsic viscosity of 0.7
A brushed artificial leather was produced in the same manner as in Example 1 except that the polytrimethylene terephthalate filament of one component of Example 6 was used. The lighting effect of this brushed artificial leather is ○,
The stretchability was ○, and the lighting effect was inferior to that of Example 1. Comparative Example 3 A microfilament of Example 1 was used as a polyethylene terephthalate-based composite filament (a composite filament obtained by extruding two types of polyethylene terephthalates having different intrinsic viscosities in a side-by-side type at a mass ratio of 1: 1.
The intrinsic viscosity is 0.66 on the high viscosity side and 0.50 on the low viscosity side.
Except that the modified artificial leather was used in the same manner as in Example 1. The artificial hair leather thus produced had a writing effect of Δ and a stretchability of ○, and the writing effect was inferior to that of Example 1. Comparative Example 4 The single fiber fineness of the ultrafine fiber of Example 1 was 1.5
A brushed artificial leather was produced in the same manner as in Example 1 except that dtex was changed to dtex. The writing effect of this brushed artificial leather was Δ, and the stretchability was ○, and the writing effect was inferior to that of Example 1. Example 2 An artificial leather was produced in the same manner as in Example 1 except that the ultrafine fibers of Example 1 were changed to composite filaments having a high viscosity side of 0.88 and a low viscosity side of 0.70. did. The lighting effect of the obtained brushed artificial leather was ◎, and the stretchability was ○. As in Example 1, the lighting effect was excellent. Example 3 In Example 1, the fiber constituting the taffeta was a polyethylene terephthalate-based composite filament (a composite filament obtained by extruding two types of polyethylene terephthalate having different intrinsic viscosities in a side-by-side type at a ratio of 1: 1. , The intrinsic viscosity is 0.66 on the high viscosity side,
A brushed artificial leather was produced in the same manner as in Example 1 except that the low viscosity side was changed to 0.50). The resulting brushed artificial leather had a writing effect of ◎ and a stretch property of △. According to the present invention, brushed artificial leather having a soft texture and particularly excellent in lighting effect can be obtained.

Claims (1)

Claims: 1. An artificial leather comprising a fiber entangled body containing ultrafine fibers having a single fiber fineness of 1.1 dtex or less and a polymer elastic body and having a brushed surface, The fiber is
Artificial leather characterized by a latent crimp-expressing polyester composite fiber in which two types of polytrimethylene terephthalate having an intrinsic viscosity difference of 0.05 to 0.40 (dl / g) are composited with each other in a side-by-side type. .