Crease-free synthetic leather and preparation method thereof

Abstract

The present invention provides a kind of crease-free synthetic leather and preparation method thereof, the crease-free synthetic leather comprises a base fabric and a wet base fabric composed of a foaming slurry coated on the base fabric, the surface of the wet base fabric is treated with an organosilicon treatment agent to form a hand-feel layer; the base fabric is a mercerized velvet; by mass, the raw materials for preparing the foaming slurry include 48 to 52 parts of low modulus super soft polyurethane resin, 5 to 8 parts of soft polyvinyl chloride, 60 to 64 parts of N, N-dimethylformamide, 45 to 48N-methylpyrrolidone, 0.8 to 1.2 parts of water-based color paste, 0.5 to 0.8 parts of antioxidant, 28 to 32 parts of filler; the filler is composed of organic montmorillonite powder, potassium tartrate powder, and magnesium silicide powder. The present invention ensures that the synthetic leather has good anti-folding performance while also ensuring that it has good hand feel and warmth retention.

Description

Technical Field

[0001] The invention belongs to the technical field of polyurethane synthetic leather manufacturing, and particularly relates to crease-free synthetic leather and a preparation method thereof. Background Art

[0002] The invention patent with the authorization announcement number CN 104674564 B provides a method for producing crease-free synthetic leather, comprising the following steps: S1: preparing a first material component, which comprises 80 to 100 parts of a polyamide resin, 1 to 10 parts of an organic montmorillonite, and 0.2 to 0.8 parts of an antioxidant, by weight; S2: blending and granulating the first material component to form a modified polyamide resin; S3: preparing a second material component, which comprises a polyamide resin and a modified polyamide resin formed in step S2, by weight, the modified polyamide resin is 100 parts and the polyamide resin is 25 to 35 parts; S4: processing the second material component into a base fabric; S5: preparing the base fabric formed in step S4, and impregnating the base fabric in polyvinyl alcohol; S6: preparing a third material component, which comprises 100 parts of a polyester polyurethane having a solid content of 40%, by weight. , 100-120 parts of dimethylformamide, 10-15 parts of porogen, 1-4 parts of surfactant, 5-10 parts of solvent colorant, 2-5 parts of fluorine polymer; S7: take out the base fabric impregnated in step S5, and immerse it in a solution containing a third material component; S8: take out the base fabric impregnated in step S7, and wash it with water; S9: dry and shape the base fabric washed in step S8; S10: attach a pattern layer to the base fabric treated in step S9 through an adhesive layer; the adhesive layer is formed by evaporating solutes from a first solution, and the first solution, by weight, contains 25-45 parts of polyether polyurethane with a solid content of 40% and 55-75 parts of thermoplastic polyester with a solid content of 60%; the pattern layer is formed by evaporating solutes from a second solution, and the second solution is a polyurethane solution with a solid content greater than 65%.

[0003] In general, the invention patent No. CN 104674564 B uses organic montmorillonite to modify polyamide resin, so that the polyamide has a higher modulus, higher impact resistance and tensile elongation, thereby solving the problem that traditional synthetic leather is prone to creases after multiple bending. However, the synthetic leather prepared according to the method disclosed in the invention patent specification also has certain defects, mainly that the hand feel is not soft enough and the warmth retention is not ideal. Summary of the invention

[0004] The purpose of the present invention is to ensure that the synthetic leather has good anti-bending performance while effectively overcoming the technical defects of the above-mentioned prior art that the hand feel is not soft enough and the warmth retention is not ideal. This purpose is achieved through the following technical solutions:

[0005] A crease-free synthetic leather comprises a wet-fabric base composed of a base fabric and a foaming slurry coated on the base fabric, wherein the surface of the wet-fabric base is treated with an organic silicon treatment agent to form a hand-feeling layer; the base fabric is mercerized velvet; the raw materials for preparing the foaming slurry comprise, by weight, 48 to 52 parts of low modulus super-soft polyurethane resin, 5 to 8 parts of soft polyvinyl chloride, 60 to 64 parts of N,N-dimethylformamide, 45 to 48 parts of N-methylpyrrolidone, 0.8 to 1.2 parts of water-based color paste, 0.5 to 0.8 parts of antioxidant, and 28 to 32 parts of filler; the filler consists of organic montmorillonite powder, potassium tartrate powder, and magnesium silicide powder.

[0006] On the basis of the above technical solution, the present invention can add the following technical means:

[0007] The thickness of the base fabric is 0.7 mm.

[0008] In the filler, the mass ratio of organic montmorillonite powder, potassium tartrate powder and magnesium silicide powder is 3:2:1.

[0009] The present invention also provides a method for preparing the crease-free synthetic leather, comprising the following steps:

[0010] Step 1, selection and cleaning of base fabric: mercerized velvet is selected as the base fabric, clean water is added to the water tank, the base fabric is put into the water tank through the cloth guide rack, and cleaned at room temperature at a line speed of 19m / min;

[0011] Step 2, preparation of foaming slurry: under stirring, add 60-64 parts of N,N-dimethylformamide, 45-48 parts of N-methylpyrrolidone, 48-52 parts of low modulus super soft polyurethane resin, 5-8 parts of soft polyvinyl chloride, 0.8-1.2 parts of water-based color paste, 0.5-0.8 parts of antioxidant, 28-32 parts of filler into the reaction kettle, evacuate for 90 minutes to make the viscosity reach 500-530 CPS / 25°C, and then filter with a 60-80 mesh screen to obtain a foaming slurry;

[0012] Step 3, coating: After washing with water, the base fabric is ironed flat once with a high-pressure ironing wheel, and some of the water is dried. The gap between the coating stations is adjusted, and the foaming slurry is transported to the coating tank and coated on the surface of the base fabric through the gap. The coating thickness is 0.18 mm and the line speed is 8 m / min.

[0013] Step 4, preparation of wet-fabric base fabric: the coated base fabric is solidified in a solidification tank with a sugar content of 14-16%, and then washed, ironed, dried, and the back surface is ground to obtain wet-fabric base fabric;

[0014] Step 5, preparation of semi-finished veneer leather: coating a layer of 0.15 mm colored soft polyurethane coating on the flat release paper, drying and coating a layer of low modulus resin again, baking at a temperature of 100-120° C. until semi-dry, laminating with the back of wet fabric base, passing through 12 rounds of ironing wheels and drying, peeling off to obtain the semi-finished veneer leather;

[0015] Step 6, formation of the pattern layer: using a flower suction machine to treat the surface of the semi-finished veneer leather at a high temperature of 150-160° C. to form a pattern layer;

[0016] Step 7, formation of a hand-feel layer: a layer of organic silicone water-based skin-feel treatment agent is coated on the pattern layer by a mesh wheel of a roller coater, and dried at a temperature of 120-130° C. to form a hand-feel layer.

[0017] Furthermore, when executing step 1, the thickness of the selected base fabric is 0.7 mm.

[0018] The main beneficial effects of the present invention are as follows:

[0019] By rationally selecting various raw materials for preparing synthetic leather, including rationally selecting base fabric, the synthetic leather of the present invention has the remarkable advantages of thick texture, soft hand feeling, soft gloss, wear resistance and durability, good warmth retention, elasticity, strong anti-bending performance, and not easy to wrinkle. In short, the present invention ensures that the synthetic leather has good anti-bending performance while also ensuring that it has good hand feeling and warmth retention. DETAILED DESCRIPTION

[0020] In order to more fully describe the technical solution of the present invention, an embodiment of the present invention is introduced below.

[0021] A crease-free synthetic leather comprises a base fabric and a wet-fabricated base fabric composed of a foaming slurry coated on the base fabric, wherein the surface of the wet-fabricated base fabric is treated with an organic silicon treatment agent to form a hand-feeling layer; the base fabric is a mercerized velvet; the raw materials for preparing the foaming slurry include 48 to 52 parts of low modulus super-soft polyurethane resin, 5 to 8 parts of soft polyvinyl chloride, 60 to 64 parts of N, N-dimethylformamide, 45 to 48 parts of N-methylpyrrolidone, 0.8 to 1.2 parts of water-based color paste, 0.5 to 0.8 parts of antioxidant, and 28 to 32 parts of filler by mass; the filler is composed of organic montmorillonite powder, potassium tartrate powder, and magnesium silicide powder. The main functions of potassium tartrate powder and magnesium silicide powder are to improve the anti-bending performance of the synthetic leather, while the main function of the organic montmorillonite powder is to improve the hand feel of the synthetic leather.

[0022] In this embodiment, the base fabric is mercerized velvet with a thickness of 0.7 mm. In the filler, the mass ratio of organic montmorillonite powder, potassium tartrate powder and magnesium silicide powder is 3:2:1.

[0023] The method for preparing the crease-free synthetic leather comprises the following steps:

[0024] Step 1, selection and cleaning of base fabric: select mercerized velvet with a thickness of 0.7 mm as the base fabric, add clean water to the water tank, put the base fabric into the water tank through the cloth guide rack, and clean it at room temperature at a line speed of 19 m / min;

[0025] Step 2, preparation of foaming slurry: under stirring, add 60-64 parts of N,N-dimethylformamide, 45-48 parts of N-methylpyrrolidone, 48-52 parts of low modulus super soft polyurethane resin, 5-8 parts of soft polyvinyl chloride, 0.8-1.2 parts of water-based color paste, 0.5-0.8 parts of antioxidant, 28-32 parts of filler into the reaction kettle, evacuate for 90 minutes to make the viscosity reach 500-530 CPS / 25°C, and then filter with a 60-80 mesh screen to obtain a foaming slurry;

[0026] Step 3, coating: After washing with water, the base fabric is ironed flat once with a high-pressure ironing wheel, and some of the water is dried. The gap between the coating stations is adjusted, and the foaming slurry is transported to the coating tank and coated on the surface of the base fabric through the gap. The coating thickness is 0.18 mm and the line speed is 8 m / min.

[0027] Step 4, preparation of wet-fabric base fabric: the coated base fabric is solidified in a solidification tank with a sugar content of 14-16%, and then washed, ironed, dried, and the back surface is ground to obtain wet-fabric base fabric;

[0028] Step 5, preparation of semi-finished veneer leather: coating a layer of 0.15 mm colored soft polyurethane coating on the flat release paper, drying and coating a layer of low modulus resin again, baking at a temperature of 100-120° C. until semi-dry, laminating with the back of wet fabric base, passing through 12 rounds of ironing wheels and drying, peeling off to obtain the semi-finished veneer leather;

[0029] Step 6, formation of the pattern layer: using a flower suction machine to treat the surface of the semi-finished veneer leather at a high temperature of 150-160° C. to form a pattern layer;

[0030] Step 7, formation of a hand-feel layer: a layer of organic silicone water-based skin-feel treatment agent is coated on the pattern layer by a mesh wheel of a roller coater, and dried at a temperature of 120-130° C. to form a hand-feel layer.

Claims

1. A crease-free synthetic leather, comprising a base fabric and a wet-fabricated base fabric composed of a foaming slurry coated on the base fabric, characterized in that: The surface of the wet-fabric base is treated with an organic silicon treatment agent to form a hand-feeling layer; the base fabric is mercerized velvet; in terms of mass, the raw materials for preparing the foaming slurry include 48 to 52 parts of low modulus super-soft polyurethane resin, 5 to 8 parts of soft polyvinyl chloride, 60 to 64 parts of N,N-dimethylformamide, 45 to 48 parts of N-methylpyrrolidone, 0.8 to 1.2 parts of water-based color paste, 0.5 to 0.8 parts of antioxidant, and 28 to 32 parts of filler; the filler is composed of organic montmorillonite powder, potassium tartrate powder, and magnesium silicide powder. The main functions of potassium tartrate powder and magnesium silicide powder are to improve the flexural resistance of synthetic leather, and the main function of organic montmorillonite powder is to improve the hand feel of synthetic leather; in the filler, the mass ratio of organic montmorillonite powder, potassium tartrate powder, and magnesium silicide powder is 3:2:

1.

2. The crease-free synthetic leather according to claim 1, characterized in that: The thickness of the base fabric is 0.7 mm.