JPH0367148B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for rapidly and uniformly dispensing a solution of an elastomeric polymer (hereinafter sometimes simply referred to as elastomeric polymer) containing polyurethane as a main component into the voids of a fibrous base material containing ultrafine fibers. The present invention relates to a method for manufacturing a leather-like sheet material to be filled.

Natural leather has excellent mechanical properties, durability, flexibility, and excellent workability, so it is used for shoes, bags, etc.
It has been widely used for bags and clothing. However, since natural leather is expensive and has a limited production volume, artificial leather has been developed as an alternative material, but it has not been possible to obtain a material with texture and physical properties that closely resemble natural leather. Recently, by using a fibrous base material containing ultrafine fibers, it has become possible to obtain artificial leather that has a texture and physical properties that closely resemble natural leather.

However, this method using a fibrous base material containing ultrafine fibers does not allow the fibrous base material to be quickly and uniformly impregnated with an elastomeric polymer solution. The quality was also not favorable.

That is, when a fibrous base material containing ultrafine fibers is impregnated with an elastic polymer solution by a normal method, a large number of air bubbles are present in the impregnated resin solution.
The result is a product that is far from natural leather in both texture and physical properties. In order to improve this drawback, it is necessary to compress a fibrous base material containing ultrafine fibers in an elastomeric polymer solution and remove the air inherent in the fibrous base material. Because it contains fibers, the air contained therein cannot be removed smoothly, and the process of compressing the fibrous base material in the elastomeric solution must be repeated many times by using many impregnating baths with the elastomeric polymer solution. It was something that should not have happened.

The present invention improves the shortcomings of these conventional methods and eliminates the need to repeatedly immerse and compress a fibrous base material containing ultrafine fibers in an elastomer solution in a large number of elastomer solution impregnation baths. Also, quickly and
It is an object of the present invention to provide a method for producing a leather-like sheet-like material by uniformly impregnating a fibrous base material containing ultrafine fibers with an elastic polymer solution and wet-coagulating the elastic polymer solution.

That is, the method for producing a leather-like sheet material of the present invention involves impregnating a fibrous base material containing ultrafine fibers with a water-miscible organic solvent solution of an elastic polymer mainly composed of polyurethane, and then impregnating the elastic polymer with a water-miscible organic solvent solution. In a method for producing a leather-like sheet material by removing a water-miscible organic solvent in a non-solvent mainly composed of water, polyethylene glycol lauryl ether is applied to a fibrous base material containing ultrafine fibers in advance. 0.01 to 3.0% of the material should be adhered.

The ultrafine fiber used in the present invention has a fineness of
1.5 denier or less, preferably polyester fibers such as polyethylene terephthalate, polybutylene terephthalate, and polybutylene naphthalate, or polyester dicarboxylic acid components containing an appropriate amount of copolymerized components such as isophthalic acid, benzoic acid, and sulfoisophthalic acid. Copolymerized polyester fibers made of copolymerized polyesters, mixed spun fibers containing 50% by weight or more of these polyesters, composite fibers, or polyamide fibers such as 6-nylon, 6,6-nylon, etc. can be used.

Further, the fibrous base material containing ultrafine fibers used in the present invention may be in any form such as nonwoven fabric, woven fabric, or knitted fabric, as long as the above-mentioned ultrafine fibers are used.

The elastic polymer used in the present invention is mainly composed of polyurethane elastomer, and more specifically, polyethylene glycol with a molecular weight of 500 to 5000,
Consisting of polyalkylene ether glycols such as polyethylene propylene ether glycol and polytetramethylene ether glycol, polyester diols such as polyethylene adipate and polycabrolactone, alone or in mixtures, and diisocyanates such as diphenylmethane diisocyanate, tolylene diisocyanate, and xylylene diisocyanate. Products whose main component is polyurethane, which is obtained by subjecting a prepolymer to chain extension reaction with a chain extension agent such as ethylene glycol, 1.4-butanediol, xylene, propylene diamine, hexamethylene diamine, hydrazine, dicarboxylic acid hydrazide, or aminocarboxylic acid hydrazide, can be used. .

As the water-miscible organic solvent used to dissolve the elastic polymer, N,N-dimethylformamide, dioxane, tetrahydrofuran, acetone, etc. can be used.

The polyethylene glycol lauryl ether used in the present invention is an addition polymer in which ethylene oxide is added to lauryl alcohol,
HLB (an indicator that shows the balance between hydrophilicity and lipophilicity,
Those with an HLB of 8 to 14 (indicated by a numerical value of 0 to 20) are preferable, and those with an HLB of 9 to 11 are particularly preferable.

In order to attach polyethylene glycol lauryl ether to fibrous substrates containing ultrafine fibers,
It is preferable to use an organic solvent solution or aqueous solution such as toluene, xylene, methyl alcohol, isopropyl alcohol, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, acetone, cyclohexane, cyclohexanone, dioxane, dimethyl formamide, etc., and the attachment can be done by dipping. It can be carried out by various methods such as , gravure method, spray method, etc., but it is necessary to uniformly adhere it to the fibrous base material containing ultrafine fibers. Note that after applying the organic solvent solution or aqueous solution of polyethylene glycol lauryl ether, it is necessary to remove the solvent or water by drying or the like.

The adhesion amount of polyethylene glycol lauryl ether to fibrous base materials including ultrafine fibers is 0.01 to 3.0
%, preferably 0.03 to 1.0%. If the amount of polyethylene glycol lauryl ether attached is less than 0.01% of the weight of the fibrous base material, the rate of penetration of the elastomer solution into the fibrous base material will not be promoted, and if it exceeds 30%, the rate of penetration of the elastomer solution into the fibrous base material will be reduced. The rate of penetration into the fibrous base material is almost at equilibrium, and no effect is observed when using a large amount. Rather, polyethylene glycol lauryl ether is eluted into the non-solvent in the coagulation bath during wet coagulation of the elastomeric polymer solution, resulting in bubbling of the non-solvent in the coagulation bath and non-volatile release during recovery of the organic solvent eluted in the coagulation bath. This is not preferable since the amount of residue increases, and is also economically disadvantageous.

It is particularly effective to attach polyethylene glycol lauryl ether to fibrous substrates containing ultrafine fibers of 1.0 denier or less.

The present invention involves attaching polyethylene glycol lauryl ether to a fibrous base material containing ultrafine fibers in an amount of 0.01 to 3.0% by weight of the fibrous base material, and then applying a water-miscible organic solvent solution of an elastomeric polymer containing polyurethane as a main component to this. Since the elastomeric polymer solution is impregnated quickly and uniformly into the fibrous base material containing ultrafine fibers, unlike conventional methods, the fibrous base material containing ultrafine fibers is impregnated with the elastomeric polymer solution. It is preferable in terms of equipment and process, since it is not necessary to use many tanks and repeat the process of compressing the elastic polymer solution many times.

In addition, the leather-like sheet material obtained by the method of the present invention has no coarse pores in the elastic polymer mainly composed of polyurethane, and therefore has an extremely smooth surface, which is preferable. Ta. This is thought to be because the fibrous base material containing ultrafine fibers is rapidly and uniformly impregnated with the elastomeric polymer solution containing polyurethane as a main component, so that no air inherent in the base material remains.

Examples of the present invention are listed below, but the present invention is not limited to these Examples.

Example Made of 30% polyethylene terephthalate fiber of 1.5 denier with a length of 35 mm and 70% of polyethylene terephthalate fiber of 0.8 denier with a length of 51 mm, exchanged by needle punching at 250 g/m ²
A fibrous base material with a thickness of 1.2 mm was obtained.

This fibrous base material is immersed in a 1.0% aqueous solution of polyethylene glycol lauryl ether (HLB: 9.8) and then squeezed with a mangle, so that 70% by weight of the polyethylene glycol lauryl ether aqueous solution is attached to the fibrous base material, This was dried at a temperature of 120°C. The obtained fibrous base material had attached polyethylene glycol lauryl ether corresponding to 0.7% of the weight of the fibrous base material.

When this fibrous base material with polyethylene glycol lauryl ether attached was immersed in a dimethyl formamide solution (solid content 12%) of Crysbon 8166 (manufactured by Dainippon Ink & Chemicals Co., Ltd.: polyurethane resin solution), it instantly Impregnated with polyurethane resin solution. The liquid was then squeezed using a drive roll with a gap of 110 mm, then introduced into a 20°C water bath to solidify and desolvent, and then immersed in a 60°C hot water bath to completely remove the solvent. After dehydration, it was dried at 130°C. A leather-like sheet material was obtained. The polyurethane resin layer of the resulting leather-like sheet was extremely uniform with no coarse pores, and had excellent surface smoothness.

Comparative Example The same fibrous base material used in Example 1 was immersed in a 1.0% aqueous solution of sodium dioctyl sulfosuccinate, which is conventionally considered to be the most effective penetrant, and then squeezed with a mangle. An aqueous sodium solution was applied to the fibrous base material in an amount of 70% by weight, and this was dried at a temperature of 120° C. to obtain a fibrous base material to which 0.7% by weight of sodium dioctyl sulfuccinate was adhered.

This fibrous base material was immersed in a polyurethane resin solution in the same manner as in Example 1, but even after being left in the polyurethane resin solution for 30 minutes, the polyurethane resin solution did not completely impregnate the fibrous base material.

A leather-like sheet was obtained by leaving it in a polyurethane resin solution for 30 minutes, removing the solvent and drying it under the same conditions as in Example 1. It was obvious that there were many coarse pores, and the polyurethane resin solution was not uniformly impregnated into the fibrous base material.

In addition, this leather-like sheet material had a large number of coarse pores, so the surface was uneven and lacked smoothness.

Claims (1)

[Claims] 1. A fibrous base material containing ultrafine fibers is impregnated with a water-miscible organic solvent solution of an elastomeric polymer mainly composed of polyurethane, and then the water-miscible organic solvent of the elastomeric polymer is mixed with a non-solvent mainly composed of water. A method for producing a leather-like sheet material by removing the polyethylene glycol lauryl ether in a fibrous base material made of ultrafine fibers in an amount of 0.01 to 3.0% of the weight of the base material in advance. A method for producing a leather-like sheet material.