JPH0791783B2 - Sheet material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a sheet-like material having high hygroscopicity, water absorption and moisture release.

[Conventional technology]

Conventionally, there are many fibrous sheet-like materials composed of a fiber-entangled non-woven fabric and an elastic polymer or a leather-like sheet-like material obtained by applying a polymer film mainly composed of an elastic polymer to the fibrous sheet-like material and finishing. Has been made. Most of them were related to the modification of sensory performances such as the texture of the sheet-like material, the waist (drapeability), measures against uneven stretch when stretched, and the napping property of the fiber.

[Problems to be Solved by the Invention]

The conventional fibrous sheet material is obtained by shrinking a entangled fiber and densifying it by refraction deformation caused by the shrinking deformation. Therefore, the obtained fibrous sheet-like material has a hard texture and is poor in fullness and roundness. Furthermore, the conventionally used synthetic fibers have low water absorption and hygroscopicity, and when a conventional fibrous sheet or leather-like sheet is processed into shoes, for example, they have low water absorption and hygroscopicity. In addition, it had an unpleasant covering with a dull feeling due to poor moisture release and water characteristics.

An object of the present invention is to provide a fibrous sheet-like material and a leather-like sheet-like material which have high hygroscopicity, water absorption and moisture release, a texture with a fullness and roundness, and a stable morphology.

[Means for Solving the Problems]

That is, the present invention provides a composite fiber in which a polyvinyl alcohol-based polymer having a saponification degree of A mol% and a polyvinyl alcohol-based polymer having a saponification degree of B mol% are bonded in a side-by-side type or an eccentric core-sheath type (AB). Is 0.2 to 2.5,
A polyvinyl alcohol composite fiber having a weight ratio of a polyvinyl alcohol polymer having a saponification degree of A mol% to a polyvinyl alcohol polymer having a saponification degree of B mol% and a polyvinyl alcohol polymer having a saponification degree of B mol% is 2: 8 to 8: 2 is used. A sheet-shaped article, characterized in that a non-woven fabric containing at least wt% is provided with a polymer mainly composed of an elastic polymer.

The polyvinyl alcohol-based composite fiber used in the present invention includes a polyvinyl alcohol-based polymer having a saponification degree of A mol% (hereinafter also simply referred to as PVA-A) and a polyvinyl alcohol-based polymer having a saponification degree of B mol%. The combined fiber (hereinafter sometimes simply referred to as PVA-B) is a composite fiber joined in a side-by-side type or an eccentric core-sheath type, but the side-by-side type is preferable in terms of crimp development ability.

In the present invention, the average degree of polymerization of PVA-A is preferably 1,400 or more, and particularly preferably in the range of 1,500 to 13,000. The degree of saponification is required to be 98.0 mol% or more, preferably 99.8 mol% or more. The average degree of polymerization of PVA-B is preferably 1,300 or more, and particularly preferably in the range of 1,400 to 12,500. The degree of saponification is 0.2 mol% to 2.5 mol% compared to PVA-A.
It must be low and preferably has a saponification degree of 98.0-9.
It is a polymer in the range of 6.0%. Here, the saponification degree of PVA-A is set to 98.0 mol% or more in order to maintain the flexibility and stretchability of the fiber and reduce the dissolution weight loss. The difference in saponification degree between PVA-A and PVA-B is 0.2
If it is less than mol%, there is no difference in water swelling property between the two types of PVA joined together, and sufficient crimping is not expressed. When the difference in the degree of saponification exceeds 2.5 mol%, crimped fibers having a good morphology are obtained, but PVA with a lower degree of saponification dissolves in water and the fibers stick and cure during repeated use. However, the crimped fiber is lost, and the crimped fiber does not have water resistance. More preferably, the difference in the degree of saponification is within 0.5 mol% to 1 mol%.

Two kinds of PVA-A and B having different saponification degrees are respectively dissolved in a solvent to prepare two kinds of polyvinyl alcohol spinning stock solutions. Also, preferably between PVA-A, B together with the degree of saponification,
It is also preferable for the average degree of polymerization to have a difference of 50 to 300 in terms of self-crimp expression and crimp morphology stability. Furthermore, PVA-
For A and / or B, a colorant selected from an inorganic pigment, an organic pigment or a dye having a desired color tone is added to the polymer.
It is also preferable to add 0.5 to 5% by weight to prepare a spinning dope that is colored. Then, the adjusted polyvinyl alcohol spinning dope is spun by a wet spinning method or a dry spinning method by using, for example, a joining type composite spinneret to obtain a polyvinyl alcohol-based composite fiber, and the polyvinyl alcohol-based composite fiber is stretched and imparted with an oil agent. Etc. to obtain a composite fiber having a single fiber fineness of 0.8 to 10 denier. The bonding ratio (weight ratio) of PVA is PVA-A: PVA-B = 2: 8 to 8: 2.
When the ratio of A-A is less than 20%, the fibers bonded by being influenced only by the shrinkage behavior of PVA-B do not develop crimp, and conversely, when it is 80% or more, the ratio of PVA-B The shrinkage stress is so small that it cannot shrink and no crimping occurs. Preferably, the bonding ratio of PVA is 4: 6 to 6: 4, whereby a stable crimp can be expressed without peeling of the bonded portion, good morphological stability, and crimp A bulky composite fiber is obtained by expression.

The crimped fiber may have any cross-sectional shape such as circular, flat, triangular, T-shaped or Y-shaped.

The composite fiber thus obtained is capable of exhibiting a high degree of three-dimensional crimp by the subsequent heat treatment, thereby maintaining the bulkiness of the product. The heat treatment can be performed, for example, in hot water at a temperature of 80 to 90 ° C., wet heat at 110 to 120 ° C., and dry heat up to about 150 ° C., but it is most preferable to perform the heat treatment in hot water. Is.

In the present invention, the polyvinyl alcohol-based composite fiber is mechanically crimped if necessary and cut to give a fiber length of 30.
Use short fibers of ~ 100 mm.

20% by weight or more of the fiber, preferably 50% by weight
The above is used as raw cotton for non-woven fabric. If necessary, other synthetic fibers such as polyethylene terephthalate, ethylene terephthalate copolymer, polyester fiber made of polybutylene terephthalate, 6-nylon,
At least one kind of synthetic fiber selected from polyamide fiber such as 66-nylon, 610-nylo, 11-nylon and 12-nylon, polypropylene fiber, acrylic fiber and the like may be mixed to form the raw cotton for the non-woven fabric. Although the polyvinyl alcohol-based conjugate fiber may be used as the nonwoven fabric alone, it facilitates the self-crimping of the conjugate fiber to form a bulky nonwoven fabric and retains the morphological stability of the nonwoven fabric when the sheet material absorbs a large amount of water. Therefore, it is generally desirable to mix 20% by weight or more of other synthetic fibers.

A mixture of polyvinyl alcohol fibers and other synthetic fibers is used to form a fiber web through a card or a random web bar, and a random web, cross-lap web or parallel web having a desired basis weight is formed. The obtained fiber web is treated by a needle punching method or a hydroentangling method alone or in combination to obtain a fiber-entangled nonwoven fabric. The basis weight of the fiber-entangled nonwoven fabric is determined depending on the desired product, but is generally in the range of 50 to 1500 g / m ² . The obtained fiber-entangled nonwoven fabric is treated in moist heat or hot water to cause polyvinyl alcohol fibers to self-crimp, thereby forming a bulky nonwoven fabric.

Then, a polymer mainly composed of an elastic polymer is applied as a binder resin inside the fiber-entangled nonwoven fabric to obtain the sheet-like material of the present invention. Here, the polymer mainly composed of an elastic polymer is a polymer diol having an average molecular weight of 500 to 3,000, for example, at least one kind selected from polyester diol, polyether diol, polyester ether diol, polycarbonate diol and polylactone diol. Polymer diols and aromatic diisocyanates such as tolylene diisocyanate, xylene diisocyanate, phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate. ,
Polyurethane and polyacrylate obtained by reacting at least one organic diisocyanate selected from alicyclic and aliphatic organic diisocyanates with a low molecular weight compound having at least two active hydrogen atoms as a chain extender , At least one elastic polymer selected from acrylonitrile-butadiene (styrene) copolymer and the like, and further an elastic polymer obtained by adding synthetic rubber, polyester elastomer, polyvinyl chloride, etc., if necessary. Is a polymer.

This polymer is dissolved in a solvent or dispersed in a dispersant, and if necessary, an additive selected from a colorant, a coagulation regulator, a release agent, a plasticizer, a stabilizer, an antioxidant, a light resistance stabilizer and the like. The fiber-entangled nonwoven fabric is impregnated with the polymer composition obtained by blending. After that, the polymer is treated with a non-solvent to solidify it by a wet coagulation method, the solvent is removed by heating to remove the solvent or the dispersant to coagulate it by a solidification method or a combination thereof, which is washed if necessary and dried. It can be made into a sheet. This sheet-like material may be subjected to coloring treatment, softening treatment, nap treatment on the surface and the like to obtain a product.

Further, a coating layer made of a polymer mainly composed of an elastic polymer may be provided on the surface of the sheet-like material, and the sheet-like material may be calendered, sliced and / or buffed on the surface of the sheet-like material. Obtained by smoothing by treatment, etc., and providing the smoothed cotton with a porous layer and / or a non-porous layer of a polymer mainly composed of polyurethane or a polymer mainly composed of plasticized polyvinyl chloride. You can Further, in the production of a sheet-like product, it can also be obtained by impregnating a fiber-entangled nonwoven fabric with a polymer liquid, further applying a polymer liquid mainly containing an elastic polymer on one surface, and then solidifying the polymer. it can. The obtained sheet material is subjected to coloring treatment, softening treatment, surface embossing,
Finishing treatment such as surface gloss adjustment may be performed to obtain the product.

In the present invention, by using a non-woven fabric having a specific self-crimping polyvinyl alcohol-based composite fiber as a constituent fiber, it is possible to obtain bulkiness by good self-crimping and a synergistic effect of the characteristics of polyvinyl alcohol. A fibrous sheet-like material or leather-like sheet-like material having high hygroscopicity and water-absorbing property, good oil and drug retention, non-greasy feeling and good drying property can be obtained.

The sheet-like material of the present invention is suitable for use as a leather-like sheet material in the field of shoes, bags, bags, interiors, backing sheet materials, and the like.

〔Example〕

Next, embodiments of the present invention will be described with reference to specific examples, but the present invention is not limited to these examples.
The parts and% in the examples relate to the weight unless otherwise specified.

Example 1 Polyvinyl alcohol A ₁ having an average polymerization degree of 1,800 and a saponification degree of 99.97 mol%, 25% of polyvinyl alcohol having an average polymerization degree of 1750 and a saponification degree of 97.2 mol%, and polyvinyl alcohol A ₁ of 75
% Mixed mixed polyvinyl alcohol B ₁ was dissolved in a solvent to prepare a spinning dope. Each spinning solution uses a joining type spinneret, and a side-by-side type composite fiber is spun at a polyvinyl alcohol joining ratio of 1: 1 by a dry method, drawn, crimped, and a polyvinyl alcohol joining type composite fiber having a fineness of 2dr (hereinafter referred to as polyvinyl alcohol fiber and After calling)
A staple fiber was obtained by cutting into a fiber length of 51 mm. 70 parts of this polyvinyl alcohol fiber, fineness 2dr, and 30 parts of polyethylene terephthalate fiber having a fiber length of 51 mm are mixed and mixed into a card, a random web through a random web, and laminated with a cross-lapper to obtain a fiber web having an average basis weight of 250 g / m ^2. It was Density The fibrous web perform needle punching needle count # 40 Total 520 punches / cm ² from both sides in the needle, then, apparently to express micro crimp polyvinyl alcohol fibers are treated with hot water at 95 ° C. A bulky nonwoven fabric of 0.19 g / cm ³ was obtained.

On the other hand, 13% of polyurethane obtained by reacting polybutylene adipate glycol having an average molecular weight of 2000, 4,4'-diphenylmethane diisocyanate and 1,4-butanediol, 1% of brown pigment, 0.15 of nonionic surfactant.
%, N, N′-dimethylformamide 85.85% polyurethane composition liquid was prepared, impregnated into the above fiber entangled nonwoven fabric, immersed in 30% N, N′-dimethylformamide aqueous solution to coagulate, and then washed with water. After drying in a hot air drier at 135 ° C., a sheet having a polyurethane content of about 36% was obtained. Both sides of this sheet material were buffed with sandpaper to form fiber naps, and one side was finished as a suede-like sheet. This suede-like sheet was dyed, softened, and brushed to make a suede-like product with a thickness of 1.2 mm.

The napped fibers of this suede-prepared product were in a bulky napped state due to micro-crimping, and were a soft sheet-like material having a round texture and a bulging feeling. This sheet material has an apparent density of 0.31g / cm ² , air permeability of 4 seconds / 100ml, and water vapor transmission rate of 2510g / m ² · 24h.
It was r. This sheet was used to make a boy's casual squeeze.

For comparison, the fiber-entangled non-woven fabric of Example 1 has a fineness of 2dr,
It was made only of polyethylene terephthalate fiber having a fiber length of 51 mm, and was similarly made to contain polyurethane and finished into a sheet. The sheet-like material was tightened with an apparent density of 0.46 g / cm ^3, and the whole had a feeling of boneness and had a thin and hard texture. This sheet was used to make a boy's casual squeeze.

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Table 1 shows the results of the sensory test conducted by wearing for a month.

That is, the shoes of the examples were hard to lose their shape and were comfortable to wear, whereas the shoes of the comparative example were hard and easy to lose their shape.

Example 2 Polyvinyl alcohol A ₂ having an average degree of polymerization of 1,800 and a saponification degree of 99.98 mol%, 20% of polyvinyl alcohol having an average degree of polymerization of 1,600 and a saponification degree of 98.0 mol%, and polyvinyl alcohol A ₂
A spinning stock solution obtained by dissolving 80% mixed polyvinyl alcohol B ₂ and a mixed polyvinyl alcohol B ₂ was prepared. Each spinning solution uses a joining type spinneret, and side-by-side composite spinning is performed with a polyvinyl alcohol joining ratio of 1: 1 by a dry method, drawn to 4.3 times, mechanically crimped and cut into a fiber length of 51 mm, and a fineness of 2 dr. A staple fiber was obtained. 80 parts of this staple fiber and fineness
2.5dr, polyethylene terephthalate fiber with fiber length 51mm 2
After mixing with 0 part, a fiber web having an average basis weight of 350 g / m ² is produced by a dry method, entangled by a needle punching method to obtain a fiber entangled nonwoven fabric, and then 40 g / m ³ water is sprayed on the web. , 135
The polyvinyl alcohol-based composite fiber was self-crimped by being treated in a hot air drying oven at ℃ for 10 minutes. The resulting non-woven fabric was one in which polyvinyl alcohol-based composite fibers developed a beautiful micro crimp, with an average basis weight of 437 g / m ² , and an apparent density.
A bulky nonwoven fabric of 0.17 g / cm ² was obtained. The nonwoven fabric was impregnated with the polyurethane solution prepared in Example 1, wet-coagulated, washed with water and dried to obtain a sheet-like material. One surface of this sheet-like material is smoothed with a heating calendar to form a smooth surface,
About 12 g / m ² of a polycarbonate-based polyurethane emulsion liquid containing a pigment on the surface is applied as a polyurethane amount, and after drying, a dye-colored polyoxyethylene / polycarbonate-based polyurethane solution is applied by a roll coating method to give a polyurethane amount of about 6 g / m ^2. m ² was applied to form a non-porous coating layer. Then, embossing, softening treatment and gloss adjustment were performed to obtain a leather-like sheet with silver.

This leather-like sheet has an apparent density of 0.33 g / cm ³ and a moisture permeability of 1
It was 310g / m ² and had a rounded flexibility and good appearance with almost no bones and fishing, and was suitable as a material for interiors and bags.

〔The invention's effect〕

The non-woven fabric comprising the self-crimping polyvinyl alcohol-based conjugate fiber of the present invention as the constituent fiber has good entangleability of the fiber due to the bulkiness of the fiber due to good self-crimping, and excellent morphological stability,
Due to the synergistic effect with the properties of polyvinyl alcohol, it has high hygroscopicity and water absorbency, good oil and drug retention, and no sticky feeling. On the other hand, it is a sheet-like material having features such as good dryability. The sheet material of the present invention is suitable for being laminated and used as a backing material for another sheet material or used as a leather-like sheet material.

Claims (1)

[Claims] 1. A composite fiber in which a polyvinyl alcohol-based polymer having a saponification degree of A mol% and a polyvinyl alcohol-based polymer having a saponification degree of B mol% are bonded in a side-by-side type or an eccentric core-sheath type. Polyvinyl which is 0.2 to 2.5, A is 98.0 or more, and the weight ratio of the polyvinyl alcohol polymer having a saponification degree of A mol% and the polyvinyl alcohol polymer having a saponification degree of B mol% is 2: 8 to 8: 2. A sheet-shaped article, characterized in that a non-woven fabric containing 20% by weight or more of an alcohol-based composite fiber is provided with a polymer mainly composed of an elastic polymer.