JPH03213587A - Sheetlike material - Google Patents

Abstract

PURPOSE:To obtain a sheetlike material having high water vapor absorption, water absorption properties, etc., by adding an elastic polymer as a binder to the interior of nonwoven fabric containing >= a specific wt.% of conjugate yarn prepared by blending PVA-based polymers having different degrees of saponification in a specific weight ratio. CONSTITUTION:Spinning dope consisting of a PVA-based polymer having A mol % degree of saponification (>=98mol%) and a PVA-based polymer having B mol% degree of saponification 0.2-2.5mol% lower than the A mol% is prepared and spun to give side-by-side type or sheath-core type conjugate yarn having self crimp generating properties in a polymerization ratio of PVA-A to PVA-B of (2:8)-(8:2). The interior of mixed yarn comprising >=20wt.% of short fibers of the conjugate yarn and another synthetic yarn is provided with a polyurethane elastic material and the material is coagulated in a wet state to give a sheetlike material having excellent bulkiness, degree of slip and shape stability, high water vapor permeability, water absorption properties and moisture release properties. The sheetlike material is suitably used as leather-like sheetlike material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a sheet material having hygroscopicity, water absorption and moisture release properties.

[Conventional technology]

Conventionally, there have been many reports regarding fibrous sheet-like materials made of fiber-entangled nonwoven fabric and elastic polymers, or leather-like sheet-like materials obtained by adding a polymer film mainly composed of an elastic polymer to the fibrous sheet-like materials. proposals have been made. Most of these were concerned with improving the sensory performance of sheet-like materials, such as the texture, waist (drapeability), countermeasures against uneven elongation when pulled, and napping properties of fibers.

[Problem to be solved by the invention]

Conventional fibrous sheet-like materials are made by applying shrinkage to the entangled fibers, and becoming densified by the refractive deformation caused by the shrinkage deformation. Therefore, the obtained fibrous sheet material has a hard feel and lacks a sense of fullness and roundness. Furthermore, conventionally used synthetic fibers have low water absorption and hygroscopicity, and when conventional fibrous sheets or leather-like sheets are processed and made into shoes, for example, they have low water absorption and hygroscopicity. Moreover, due to poor moisture dissipation and water characteristics, the covering felt stuffy and uncomfortable.

2- The purpose of the present invention is to provide a fibrous sheet-like material and a leather-like sheet-like material that have high hygroscopicity, water absorption, and moisture release properties, have a solid and rounded texture, and are stable in form. be.

[Means to solve the problem]

That is, the present invention provides a composite fiber in which a polyvinyl alcohol polymer having a saponification degree of A molar and a polyvinyl alcohol polymer having a saponification degree of B molar are joined in a side-by-side type or an eccentric core-sheath type. is 0.2 to 2.5, A is 98.0 or more, and the degree of saponification is A molar ratio polyvinyl alcohol/l14! Polyvinyl alcohol-based composite fibers containing 20% by weight or more of polyvinyl alcohol-based composite fibers with a weight ratio of 2 = 8 to 8:2 of polyvinyl alcohol-based polymers with a molar ratio of coalescence and saponification degree B are This is a sheet-like product characterized by being provided with a combination.

The polyvinyl alcohol composite fiber used in the present invention is a polyvinyl alcohol polymer with a saponification degree of A molar ratio (hereinafter sometimes simply referred to as PVA-A) and a polyvinyl alcohol polymer with a saponification degree of B molar ratio. It is a composite fiber in which PVA-B (hereinafter sometimes simply referred to as PVA-B) is joined in a side-by-side type twist or an eccentric core-sheath type, but the side-by-side type is preferable in terms of the ability to develop crimp. Yes.

In the present invention, the average degree of polymerization of PVA-A is 1.400
The above is preferable, and the range of 1,500 to 13,000 is particularly preferable. The degree of saponification is required to be 98.0 molar or higher, preferably 99.8 molar or higher. PVA-B
It is preferable that the average degree of polymerization is 1,300 or more, and the range of 1,400 to 12,500 is particularly preferable. The degree of saponification must be 0.2 moltyl and 25 molt lower than that of PVA-A, preferably a saponification degree of 980 to 9.
60 inch range polymer. Here, the degree of saponification of PVA-A is set to 98.0 molar coefficient or more in order to maintain the flexibility and elasticity of the fiber and to reduce the loss by dissolution. Furthermore, if the difference in saponification degree between PVA-A and PVAB is less than 0.2 molar, there is no difference in the water swelling properties of the two joined PVAs, and sufficient crimp does not occur. If the difference in the degree of saponification exceeds 2.5 mol, the shape is good crimped W1. However, PVA0, which has a lower degree of saponification, dissolves in water, and during repeated use, the fibers stick and harden, resulting in no crimp, and a water-resistant crimped fiber cannot be obtained. More preferably, the difference in saponification degree 'ff:
This is the case when the content is within 0.5 mol% to 1 mol%.

These two types of PVA-A and B having different degrees of saponification are dissolved in a solvent, respectively, to prepare two types of polyvinyl alcohol spinning stock solutions. Furthermore, it is preferable to provide a difference of 50 to 300 in average degree of polymerization as well as saponification degree between PVA-A and PVA-B, which is favorable for self-crimping development and crimped form stability. Furthermore, for PVA-A and/or BK, 0.5 to 5% by weight of a coloring agent selected from inorganic pigments, organic pigments, or dyes of a desired color tone is added to the polymer to prepare a colored spinning stock solution. It is also preferable. Then, the prepared polyvinyl alcohol spinning stock solution is spun using, for example, a bonded composite spinneret by a wet spinning method or a single dry spinning method to obtain a polyvinyl alcohol composite fiber. The composite fibers are subjected to treatments such as imparting to obtain composite fibers having a single fiber fineness of 08 to 10 tenier. The bonding ratio (weight ratio) of PVA is PVA-A:PVA-B=2:8 to 8:2,
When the ratio of PVA-A is less than 20%, the bonded fibers are affected only by the shrinkage behavior of PVA-B and do not develop crimp; on the other hand, when the ratio of PVA-A is 80% or more, Since the shrinkage stress of B is small, it cannot shrink and crimp does not occur. Preferably, the bonding ratio of PVA is 4:6 to 6:4.
By doing so, stable crimp can be developed without peeling of the joint, and the material has good morphological stability.
A bulky composite fiber can be obtained by developing crimp.

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

The composite fiber obtained in this way develops high three-dimensional crimp through subsequent heat treatment, and O heat treatment, which can maintain the bulkiness of the product,
For example, 80-90℃ in hot water, 110-120℃ in moist heat.
Although it is possible to carry out the process at a temperature of up to about 150°C using dry heat, it is most preferable to carry out the process in hot water.

In the present invention, this polyvinyl alcohol composite fiber is mechanically crimped if necessary and cut to obtain a fiber length of 3.
The short fibers are 0 to 100NR.

Then, the fibers are used in an amount of 20% by weight or more, preferably 50% by weight or more, to make raw cotton for non-woven fabric b. If necessary, other synthetic fibers such as polyester fibers made of polyethylene terephthalate, ethylene terephthalate copolymer, polybutylene terephthalate, 6-nylon, 6-row nylon, 610-nylon, 11-nylon, 12-nylon, etc. At least one type of synthetic fiber selected from polyamide fibers, polypropylene fibers, acrylic fibers, etc., may be used as raw cotton for nonwoven fabrics. The polyvinyl alcohol composite fiber alone may be used as a non-woven fabric, but the self-crimping of the composite fiber can be easily sifted, making it a bulky non-woven fabric, as well as improving the shape stability of the non-woven fabric when the sheet-like material absorbs a large amount of water. It is generally desirable to mix in other synthetic fibers of 20 weight percent or more to maintain the weight.

A blend of polyvinyl alcohol fibers and other synthetic fibers is passed through a card or random univer to form a fibrous web, and then made into a random web, cross-wrap web, or halal web with a desired basis weight. The obtained fibrous web is processed by a needle punch method or a hydroentanglement 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 y/m''.The obtained fiber-entangled nonwoven fabric is treated in moist heat or hot water to form polyvinyl alcohol fibers. It develops self-crimping and becomes a bulky nonwoven fabric.

Next, a polymer mainly composed of an elastic polymer is applied as a binder resin to the inside of the fiber-entangled nonwoven fabric to obtain a sheet-like article of the present invention. Here, the polymer mainly composed of an elastic polymer is at least one selected from polymer diols having an average molecular weight of 500 to -3,000, such as polyester diols, polyether diols, polyester ether diols, polycarbonate diols, and polylactone diols. One type of polymer diol and an organic diisocyanate such as tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, inphorone diisocyanate, hexa Methylene diisocyanate - A chain consisting of at least one organic diisocyanate selected from aromatic, alicyclic, and aliphatic organic diisocyanates such as toner, and a low molecular compound having at least two active hydrogen atoms f. At least one type of elastic polymer selected from polyurethane obtained by reaction as an extender, polyacrylic acid ester, acrylonitrile-butadiene (styrene) copolymer, etc., and if necessary, synthetic rubber, polyester elastomer, polychloride. It is a polymer mainly composed of an elastic polymer obtained by adding vinyl or the like.

This polymer is dissolved in a solvent or dispersed in a dispersant, and if necessary, additives selected from colorants, coagulation regulators, mold release agents, plasticizers, stabilizers, antioxidants, light stabilizers, etc. A polymer composition obtained by blending 2 is impregnated into a fiber-entangled nonwoven fabric. Thereafter, the polymer is coagulated by a wet coagulation method in which the polymer is treated with a non-solvent and coagulated, a dry coagulation method in which the solvent or dispersant is removed by heating and coagulated, or a combination thereof, and if necessary, washed. It can be dried into a sheet-like product. This sheet-like material may be subjected to a coloring treatment, a softening treatment, a raised surface treatment, etc., and then made into a product.

Further, a coating layer made of a polymer mainly composed of an elastic polymer may be applied to the surface of the sheet-like material, and the sheet-like material can be prepared by calendering the surface of the sheet-like material, slicing it, or
and a porous layer or a non-porous layer of a polymer mainly composed of polyurethane or a polymer mainly composed of plasticized polyvinyl chloride. can be obtained by giving.

In addition, 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 composed of an elastic polymer on one side, and then coagulating the polymer. The obtained sheet-like material may be subjected to finishing treatments such as coloring treatment, softening treatment, surface embossing, surface gloss adjustment, etc., as necessary, to obtain a product.

In the present invention, by using a nonwoven fabric whose constituent fibers are specific self-crimping polyvinyl alcohol-based composite fibers, the bulkiness due to good self-crimping and the synergistic effect of the properties of polyvinyl alcohol make it hygroscopic. It can be used as a fibrous sheet-like material or leather-like sheet-like material that has high water absorption, good oil and drug retention properties, is not sticky, and has good drying properties.

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

〔Example〕

Next, embodiments of the present invention will be explained using specific examples, but the present invention is not limited to these examples. Note that parts and parts in the examples refer to weight unless otherwise specified.

Example 1 Polyvinyl alcohol with an average degree of polymerization of 1.800 and saponification degree of 9997 mo/L7 and 25% polyvinyl alcohol with an average degree of polymerization of 1750 and saponification of 11i97.2 moles
A spinning dope was prepared by dissolving mixed polyvinyl alcohol B1 obtained by mixing 75 parts of polyvinyl alcohol AI in a solvent [1]. Each spinning solution was side-by-side composite spun using a joint type spinneret at a polyvinyl alcohol joint ratio of 1:1 using a dry method, drawn, and crimped to produce 1i fiber.
After forming a 2 dr polyvinyl alcohol bonded composite fiber (hereinafter referred to as polyvinyl alcohol fiber), the fiber length was 5.
Staple fibers were obtained by cutting to 1+m. 70 parts of this polyvinyl alcohol fiber and 30 parts of polyethylene terephthalate fiber with a fineness of 2 dr and a fiber length of 51 mm were mixed, and the mixture was passed through a card and a random univer to make a random univers.
Laminated with cross wrapper, average basis weight 250? A fiber web of /d was obtained. This fiber web was needle-punched from both sides with a needle with a needle count of 4-40 at a total of 520 punches/d, and then treated in hot water at 95°C to develop micro-crimps in the polyvinyl alcohol fibers to increase the apparent density. A bulky nonwoven fabric having a density of 0.19 f'/CJ was obtained.

On the other hand, 13% polyurethane obtained by reacting polybutylene adipate glycol with an average molecular weight of 2000, 4.4'-diphenylmethane diisocyanate and 1.4-butanediol, 1% brown pigment, and 0.15% nonionic surfactant. %, N,N-dimethylformamide 85.
A polyurethane composition liquid consisting of 85% was prepared, impregnated into the fiber-entangled nonwoven fabric, immersed in a 30% aqueous solution of N,N'-dimethylformamide to coagulate, and washed with water.
It was dried in a hot air dryer at 135°C to obtain a sheet having a polyurethane content of about 36 inches. Puff both sides of this sheet with sandpaper to form fiber naps,
- Finished with a suede-like sheet. This S=13 needle-like sheet is dyed, softened, and brushed to create a suede product with a thickness of about 1.2 mm.

The napped fibers of this suede preparation were in a bulky napped state due to micro-crimping, and the texture was a soft sheet-like material with a rounded and bulging feel. This sheet-like material has an apparent density of 0.31? /Ctl, air permeability 4 seconds/100d, and moisture permeability 2510f/1-24hrT.

Casual shoes for men were made from this sheet-like material.

For comparison, the fiber entangled nonwoven fabric of Example 1 was used as fiber 112d.
It was made only from polyethylene terephthalate fibers with r% fiber length of 51 mm, and was finished into a sheet-like material by similarly containing polyurethane. This sheet-like material had an apparent density of 0.469A, was compact, had a boney feel, and had a thin and hard texture.

Casual shoes for men were made from this sheet-like material.

These casual shoes were given to 10 people, 7 to 7 people, one foot at a time.
Table 1 shows the results of a sensory test performed during the month of August.

4 Table 1 In other words, the shoes of the example did not easily lose their shape and were comfortable to wear, whereas the shoes of the comparative example were hard and easily lost their shape.

Example 2 Polyvinyl alcohol A2 with an average polymerization degree of 1,800 and a saponification degree of 99.98 moles, and polyvinyl alcohol with an average polymerization degree of Kashima of 600 and a saponification degree of 98.0 moles/l/total of 20 mol, polyvinyl alcohol 80 A spinning dope was prepared by dissolving the mixed polyvinyl alcohol B2 and the mixed polyvinyl alcohol B2 in a solvent. Each spinning solution uses a bonded spinneret,
Side-by-side composite spinning was carried out using a dry method with a polyvinyl alcohol bonding ratio of 1:1, drawn 4.3 times, mechanically crimped, and cut into a fiber length of 51 m to obtain staple fibers with a fineness of 2 dr. 80 parts of this stable fiber and fineness of 2.5
dr, and 20 parts of polyethylene terephthalate fiber with a fiber length of 51 MR, and an average basis weight of 350 r/
A fiber web of "ni" is made, and after being entangled by a needle punch method to obtain a fiber entangled nonwoven fabric, the web is coated with 40% fibers.
/rr1 Spray water1. ．． The polyvinyl alcohol composite fibers were treated in a hot air drying oven at 135° C. for 10 minutes to develop self-crimping. The obtained nonwoven fabric is made of polyvinyl alcohol composite fibers with beautiful micro-crimps, and has an average basis weight of 437 f/I and an apparent density of 0.17 f/I.
A bulky nonwoven fabric of m was obtained. This nonwoven fabric was impregnated with the polyurethane solution prepared in Example 1, wet coagulated, washed with water,
A sheet-like product was obtained by drying. One side of this sheet-like material is smoothed with a heated calender to make a smooth surface, and a polycarbonate-based polyurethane emulsion liquid containing a pigment is applied to that surface in an amount of about 12% polyurethane. /111' was applied and dried, then a dye-colored polyoxyethylene/polycarbonate-based polyurethane solution was applied by roll coating to a polyurethane amount of approximately 62/? was applied to form a non-porous coating layer. Next, embossing, softening treatment, and gloss adjustment were performed to obtain a silvered leather-like sheet material.

This leather-like sheet material has an apparent density of 0.33 yA.

It had a water vapor permeability of 1310 S'/rn'', was flexible with a rounded feel, and had a good appearance with almost no bones or looseness, and was suitable as an interior material or a bag material.

〔Effect of the invention〕

The nonwoven fabric made of the self-crimping polyvinyl alcohol-based composite fibers of the present invention has good fiber entanglement due to the bulkiness due to the good self-crimping of the fibers, excellent morphological stability, and Due to the synergistic effect with these properties, it has high hygroscopicity and water absorption, and also has good retention of oils and medicines, and does not have a sticky feeling. On the other hand, it is a sheet-like material that has characteristics such as good drying properties. The sheet-like material of the present invention is suitable for use in a laminated form as an agricultural layer for other sheet-like products, or as a leather-like sheet-like material.

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Claims (1)

[Claims] (1) In a composite fiber in which a polyvinyl alcohol polymer with a saponification degree of A mol % and a polyvinyl alcohol polymer with a saponification degree of B mol % are joined in a side-by-side type or an eccentric core-sheath type, (A-B) is 0.2 ~2.5 and A
is 98.0 or more, and the weight ratio of the polyvinyl alcohol polymer having a saponification degree of A mol% to the polyvinyl alcohol polymer having a saponification degree of B mol% is 2:8 to 8:2. 1. A sheet-like article characterized in that a polymer mainly composed of an elastic polymer is provided inside a nonwoven fabric containing at least % by weight.