Method for manufacturing artificial leather

Abstract

The present invention addresses the problem of providing a method for manufacturing an artificial leather at a practically usable level without using any organic solvent and without requiring any crosslinking step with the use of a crosslinking agent. Provided is a method for manufacturing an artificial leather, said artificial leather comprising a layer of a cured product of a moisture-curable urethane hot melt resin composition, characterized in that: the moisture-curable urethane hot melt resin composition comprises an isocyanate group-containing urethane prepolymer but is free from any crosslinking agent having a hydroxyl group and / or an amino group; and the cured product layer is formed by applying the moisture-curable urethane hot melt resin composition at a rate of 0.03-0.5 kg / m2 relative to a base material.

Description

technical field

[0001] The present invention relates to a method for producing synthetic leather. Background technique

[0002] Synthetic leather made of urethane resin is widely used in the manufacture of vehicle interior materials, furniture, and moisture-permeable waterproof clothing. As the above-mentioned urethane resin, N,N-dimethylformamide (hereinafter, abbreviated as "DMF") solution of polyurethane is generally used. However, the regulation of the use of DMF in Europe or mainland China has been formalized, and the reduction of its use or the shift to solvent-free has become urgent.

[0003] In addition, synthetic leather is usually formed as a laminate consisting of a base fabric, a middle layer, and a skin layer as essential layers. The manufacturing method generally involves making a skin layer on a release paper, forming a middle layer on it, and passing an adhesive In the process of laminating the intermediate layer to the base fabric, it should be noted that ...

Examples

Embodiment

[0038] Hereinafter, the present invention will be described in more detail using examples.

Synthetic example 1

[0039] [Synthesis Example 1] Synthesis of Urethane Prepolymer (A-1)

[0040] In the reaction vessel equipped with thermometer, stirrer, inert gas inlet and reflux cooler, add the polyoxytetramethylene glycol (number average molecular weight; 1000) of 250 mass parts, the polyester polyol of 250 mass parts ( The reaction product of 1,6-hexanediol and adipic acid, number average molecular weight; 2000) was dehydrated under reduced pressure until the moisture content became 0.05% by mass or less.

[0041] Next, 133 parts by mass of 4,4'-diphenylmethane diisocyanate was added, the temperature was raised to 110° C., and the reaction was carried out for about 2 hours until the content rate of isocyanate groups became constant to obtain a urethane prepolymer ( A-1).

Embodiment 1

[0043] After the urethane prepolymer (A-1) was melted at 110°C, it was placed on the release paper of the roll coater at 0.2kg / m 2 After the amount of coating is applied, it is bonded with a non-woven fabric impregnated with urethane resin (hereinafter referred to as "impregnated non-woven fabric") in a viscous state. Stand for 2 days to obtain synthetic leather.

technical field

[0001] The present invention relates to a method for producing synthetic leather. Background technique

[0002] Synthetic leather made of urethane resin is widely used in the manufacture of vehicle interior materials, furniture, and moisture-permeable waterproof clothing. As the above-mentioned urethane resin, N,N-dimethylformamide (hereinafter, abbreviated as "DMF") solution of polyurethane is generally used. However, the regulation of the use of DMF in Europe or mainland China has been formalized, and the reduction of its use or the shift to solvent-free has become urgent.

[0003] In addition, synthetic leather is usually formed as a laminate consisting of a base fabric, a middle layer, and a skin layer as essential layers. The manufacturing method generally involves making a skin layer on a release paper, forming a middle layer on it, and passing an adhesive In the process of laminating the intermediate layer to the base fabric, it should be noted that ...

Examples

Embodiment

[0038] Hereinafter, the present invention will be described in more detail using examples.

Synthetic example 1

[0039] [Synthesis Example 1] Synthesis of Urethane Prepolymer (A-1)

[0040] In the reaction vessel equipped with thermometer, stirrer, inert gas inlet and reflux cooler, add the polyoxytetramethylene glycol (number average molecular weight; 1000) of 250 mass parts, the polyester polyol of 250 mass parts ( The reaction product of 1,6-hexanediol and adipic acid, number average molecular weight; 2000) was dehydrated under reduced pressure until the moisture content became 0.05% by mass or less.

[0041] Next, 133 parts by mass of 4,4'-diphenylmethane diisocyanate was added, the temperature was raised to 110° C., and the reaction was carried out for about 2 hours until the content rate of isocyanate groups became constant to obtain a urethane prepolymer ( A-1).

Embodiment 1

[0043] After the urethane prepolymer (A-1) was melted at 110°C, it was placed on the release paper of the roll coater at 0.2kg / m 2 After the amount of coating is applied, it is bonded with a non-woven fabric impregnated with urethane resin (hereinafter referred to as "impregnated non-woven fabric") in a viscous state. Stand for 2 days to obtain synthetic leather.

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