CN115162020A

CN115162020A - Preparation method of artificial leather with stretchability, artificial leather and automotive interior

Info

Publication number: CN115162020A
Application number: CN202210268925.9A
Authority: CN
Inventors: 江玉峰; 刘建红; 祁海涛; 仇冬旭
Original assignee: Canadian General Tower Changshu Co Ltd
Current assignee: Canadian General Tower Changshu Co Ltd
Priority date: 2022-03-18
Filing date: 2022-03-18
Publication date: 2022-10-11

Abstract

The invention relates to a preparation method of artificial leather with stretchability, the artificial leather and automotive interior, wherein the preparation method adopts a coating mode to prepare an artificial leather finished product, adopts cloth with stretchability on four sides as base cloth, forms patterns in a non-extrusion vacuum pattern absorption mode, and forms coating quality of a glue layer and a mass ratio of PVC powder to a plasticizer in a surface layer and a foaming layer. The tensile property of the finished artificial leather product finally obtained is improved, when an operator utilizes the finished artificial leather product to coat the product, the required strength of the operator for stretching the artificial leather product is reduced, the fatigue of the operator is reduced, and the coating effect and the yield of the product are improved.

Description

Preparation method of artificial leather with stretchability, artificial leather and automotive interior

Technical Field

The invention relates to the technical field of artificial leather, in particular to a preparation method of artificial leather with stretchability, artificial leather and automotive interior.

Background

The artificial leather is a plastic product with hand feeling and appearance similar to leather and can replace the artificial leather for use, and is widely applied to cases and automotive interiors.

With the development of the automobile industry, in order to meet the requirements of the end market, the number of special-shaped pieces on the automobile is increased, and some special-shaped pieces have slender sharp corners, so that when the special-shaped pieces are wrapped, an operator needs to apply a stretching force to the artificial leather to stretch the artificial leather, and effective wrapping can be achieved. The existing artificial leather products do not have high tensile property. In order to achieve a better coating effect, an operator needs to apply a larger force to the artificial leather to stretch the artificial leather to a required state, so that the fatigue of the operator is increased, the final coating effect is influenced, and the yield of products is reduced.

In addition, most of the existing artificial leathers adopt a calendering method to prepare the artificial leather, and a foaming layer and a surface layer are stretched in the calendering process, so that the finally obtained artificial leather actually loses certain stretching property; and after calendering, the intermediate product of synthetic leather (i.e. the intermediate product which is not foamed after calendering) still needs to be foamed at high temperature, in the process, the intermediate product of synthetic leather always receives a certain pulling force, and the intermediate product is further stretched, so that the stretching performance of the formed synthetic leather product is further reduced.

Disclosure of Invention

In view of the above, the present invention provides a method for preparing artificial leather having stretchability, artificial leather and automotive interior trim, which utilize a coating method, and use cloth having stretchability on four sides as a base fabric, and form patterns by non-extrusion vacuum pattern-absorbing, coating quality of a glue layer, and a mass ratio of PVC powder to plasticizer in a skin layer and a foam layer, thereby improving stretchability of the finally obtained artificial leather, facilitating stretching of the artificial leather by an operator to coat automotive interior trim products, making it easier for the operator to stretch the artificial leather, reducing fatigue of the operator during stretching, reducing pressure on the products after coating the products, ensuring coating effect of the products, and improving yield of coating the products.

The technical scheme adopted by the invention is as follows:

a method for preparing artificial leather having stretchability, the method comprising the steps of:

s100, taking release paper as a carrier, sequentially coating the release paper to form a skin layer and a foaming middle layer, and coating a glue layer on the foaming middle layer according to the mass of 70-75g per square meter; the foaming interlayer is of a layer structure of the foaming layer before foaming, the mass ratio of PVC powder to a plasticizer in the skin layer and the foaming interlayer is 0.842-1.333, and the foaming interlayer also comprises a foaming agent; the glue comprises bonding powder and a plasticizer, the bonding powder comprises PVC powder and/or chloroethylene-vinyl acetate copolymer PVC powder, and the mass ratio of the bonding powder to the plasticizer is 0.737-1.333;

s200, taking cloth with tensile property on four sides as base cloth, covering the base cloth on the glue layer, sending the base cloth into a foaming oven for foaming and plasticizing, so that a foaming middle layer is foamed to form a foaming layer, and simultaneously, glue and the base cloth form a glue base cloth layer together and are bonded with the foaming layer;

the longitudinal static stretching rate of the fabric is not less than 115%, the transverse static stretching rate of the fabric is not less than 180%, the longitudinal tearing force is not more than 15N, the transverse tearing force is not more than 15N, the pulling force required for longitudinally breaking the fabric with the width of each centimeter is 34-38N, and the pulling force required for transversely breaking the fabric with the width of each centimeter is 30-34N;

s300, removing release paper, printing a surface treatment agent on the outer side of the surface layer, and drying to form a surface treatment agent layer to obtain a semi-finished artificial leather product;

s400, heating the artificial leather semi-finished product; and then carrying out non-extrusion vacuum grain absorption on the outer surface of the semi-finished artificial leather by using a vacuum grain absorption machine to obtain the finished artificial leather, wherein the depth of the patterns of the vacuum grain absorption machine is less than or equal to the sum of the thicknesses of the surface treating agent layer, the surface layer and the foaming layer.

Preferably, in the raw materials of the skin layer and the foamed intermediate layer: 80-100 parts of PVC powder and 75-95 parts of plasticizer; the sum of the thicknesses of the skin layer and the foaming layer is 0.5-0.7mm.

Preferably, the glue comprises the following raw materials: 60-100 parts of PVC powder, 10-20 parts of polyethylene-vinyl acetate copolymer PVC powder and 75-95 parts of plasticizer; the thickness of the base cloth is 0.35-0.45mm, and the thickness of the glue between the base cloth layer and the foaming layer is less than or equal to 10 mu m.

Preferably, the mass ratio of the vinyl acetate in the chloroethylene-vinyl acetate copolymerized PVC powder is 3% -5%.

Preferably, the four-side cloth with the tensile property is 80-90g per square meter of mass and is woven by 60-90D polyester fibers.

Preferably, in the step S400, the pattern depth of the vacuum embosser is less than or equal to the sum of the thicknesses of the surface treatment agent layer and the skin layer; the vacuum degree of the vacuum line suction is 0.03-0.06Mpa, and the time of the vacuum line suction is 20-30s.

Preferably, the skin layer is a layer of a polymer,

when the mass ratio of the PVC powder to the plasticizer is more than or equal to 0.842 and less than 1.006, the vacuum degree during vacuum grain absorption is more than or equal to 0.03MPa and less than or equal to 0.04MPa;

when the mass ratio of the PVC powder to the plasticizer is more than or equal to 1.006 and less than 1.17, the vacuum degree during vacuum grain absorption is more than 0.04Mpa and less than 0.05Mpa;

when the mass ratio of the PVC powder to the plasticizer is more than or equal to 1.17 and less than or equal to 1.333, the vacuum degree during vacuum grain absorption is more than or equal to 0.05Mpa and less than or equal to 0.06Mpa.

Preferably, the skin layer has a thickness of 0.2 to 0.3mm, and the surface treatment agent layer has a thickness of 4 to 16 μm;

in the step S400, the pattern depth of the vacuum grain suction machine is 10-50 μm.

Preferably, in the step S400, the artificial leather semi-finished product is firstly heated in the infrared mode until the temperature of the outer surface reaches 140-180 ℃, and then a vacuum grain sucking machine is used for non-extrusion vacuum grain sucking on the outer surface of the artificial leather.

The invention relates to artificial leather with stretchability, which comprises a glue base cloth layer, a coating-formed foaming layer, a coating-formed surface layer and a surface treating agent layer which are sequentially laminated, wherein,

the glue base cloth layer comprises base cloth and glue, and the base cloth is cloth with tensile properties on four sides; the glue base cloth layer is bonded with the foaming layer, and the glue base cloth layer and the foaming layer are not embedded into each other;

forming patterns on the layer structure from the surface treating agent layer to the foaming layer in a non-extrusion vacuum pattern absorption mode;

wherein, under a static tensile test, the longitudinal static tensile rate of the artificial leather is 46-58%, and the transverse static tensile rate is 70-90%;

under a circular modulus test, the force required by the artificial leather for stretching 5% in the longitudinal direction is 12-18N, and the force required by stretching 5% in the transverse direction is 13-19N;

the force required for longitudinally breaking the artificial leather per centimeter of width is 60-65N, the force required for transversely breaking the artificial leather per centimeter of width is 38-45N, the longitudinal elongation at break of the artificial leather is 76-85%, and the transverse elongation at break of the artificial leather is 230-255%.

Preferably, the mass of each square meter of the cloth is 80-90g, and the cloth is woven by 60-90D polyester fibers;

the longitudinal static stretching rate of the fabric is not less than 115%, the transverse static stretching rate of the fabric is not less than 180%, the longitudinal tearing force is not more than 15N, the transverse tearing force is not more than 15N, the pulling force required for longitudinally breaking the fabric per centimeter in width is 34-38N, and the pulling force required for transversely breaking the fabric per centimeter in width is 30-34N.

Preferably, in the raw materials of the skin layer and the foaming layer: 80-100 parts of PVC powder and 75-95 parts of plasticizer; the sum of the thicknesses of the skin layer and the foamed layer is 0.5-0.7mm.

Preferably, the glue comprises the following raw materials: 60-100 parts of PVC powder, 10-20 parts of polyethylene-vinyl acetate copolymer PVC powder and 75-95 parts of plasticizer; the thickness of the base cloth is 0.35-0.45mm, and the thickness of the glue between the glue base cloth layer and the foaming layer is less than or equal to 10 mu m.

Preferably, the skin layer has a thickness of 0.2 to 0.3mm, and the surface treatment agent layer has a thickness of 4 to 16 μm; the depth of the patterns is 10-50 μm.

The invention also relates to an automobile interior trim which comprises the artificial leather with stretchability.

Preferably, the automotive trim is a door trim, a door center panel trim, a door armrest trim, an instrument panel trim, and/or a center armrest trim.

The invention has the beneficial effects that:

according to the invention, the release paper is used as a carrier, and the semi-finished artificial leather product is formed on the release paper, and in the process of preparing the finished artificial leather product, each layer in the finished artificial leather product is always free from outward tension, so that each layer structure is not stretched in the preparation process, and the stretching performance of the finished artificial leather product is improved; meanwhile, the surface layer and the foaming middle layer are also coated to form the surface layer and the foaming middle layer, so that the surface layer and the foaming middle layer are not pressed and expanded, the tensile property of the surface layer and the foaming layer in the finished artificial leather product is not lost, and the tensile property of the finished artificial leather product is ensured; secondly, the invention abandons the conventional cloth as the base cloth, and adopts the cloth with tensile property on four sides as the base cloth, because the longitudinal static stretching rate of the cloth is not less than 115 percent, the transverse static stretching rate is not less than 180 percent, the longitudinal tearing force is not more than 15N, the transverse tearing force is not more than 15N, the pulling force required for longitudinally breaking the cloth per centimeter in width is 34-38N, and the pulling force required for transversely breaking the cloth per centimeter in width is 30-34N, the base cloth has higher tensile property, thereby reducing the limit of the base cloth on the tensile property of the finished artificial leather product and improving the tensile property of the finished artificial leather product; the mass ratio of the PVC powder to the plasticizer in the skin layer and the foaming intermediate layer is 0.842-1.333, so that the skin layer and the foaming layer in the finished artificial leather product have high tensile property, and the tensile property of the finished artificial leather product is enhanced; the mass ratio of the bonding powder to the plasticizer in the glue is 0.737-1.333, so that the viscosity of the glue can reach 4500-5000cps, the glue is coated on the foaming intermediate layer according to the mass of 70-75g per square meter, the base cloth and the foaming layer can be effectively bonded, the use amount of the glue is reduced, the influence of the glue on the tensile property of an artificial leather finished product is reduced, the glue can permeate into meshes of the base cloth, an independent glue layer cannot be formed between the base cloth and the foaming layer, and the influence of a thicker glue layer on the tensile property of the artificial leather finished product is reduced; moreover, the patterns are formed in a non-extrusion vacuum pattern absorption mode, so that the glue base cloth layer and the foaming layer are not embedded into each other in the pattern forming process, and the influence of the pattern forming process on the tensile property of the finished artificial leather is prevented; in addition, the pattern depth is less than or equal to the sum of the thicknesses of the surface treatment agent layer, the surface layer and the foaming layer, so that the pattern does not influence the glue base fabric layer, the glue base fabric layer and the foaming layer are not embedded with each other, and the tensile property of the artificial leather finished product is ensured; thus, the surface layer, the foaming layer and the glue base fabric layer retain the self-stretching performance, and the self-stretching performance of the layer structures is higher, so that the formed artificial leather product can have higher stretching performance. Therefore, when the finished artificial leather product of the invention is used for coating, the force required by an operator for stretching the artificial leather product can be reduced, the fatigue of the operator can be reduced, and the coating effect and the yield of the product can be improved.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention with reference to the accompanying drawings, in which:

FIG. 1 is a flow chart of a method for manufacturing artificial leather having high stretchability;

FIG. 2 is a schematic diagram of a preferred embodiment of an artificial leather production system;

fig. 3 is a schematic sectional view of a finished artificial leather product.

In the figure: 1. unwinding a release paper roll; 2. a first coating head; 3. a first oven; 4. a second coating head; 5. a second oven; 6. a third coating head; 7. a base cloth winding roller; 8. a foaming oven; 9. an artificial leather wind-up roll; 10. a release paper wind-up roll; 11. a glue base cloth layer; 12. a foamed layer; 13. a skin layer; 14. a base coat layer; 15. and (4) top coating.

Detailed Description

The present invention will be described below based on examples, but the present invention is not limited to only these examples. In the following detailed description of the present invention, certain specific details are set forth in order to avoid obscuring the nature of the present invention, and well-known methods, procedures, and components have not been described in detail.

Further, those of ordinary skill in the art will appreciate that the drawings provided herein are for illustrative purposes and are not necessarily drawn to scale.

Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is, what is meant is "including, but not limited to".

In the description of the present invention, it is to be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

Referring to fig. 1 and 2, the present invention relates to a method for preparing artificial leather having stretchability, characterized in that the method comprises the steps of:

s100, taking release paper as a carrier, sequentially coating the release paper to form a skin layer and a foamed middle layer, and coating a glue layer on the foamed middle layer according to the mass of 70-75g per square meter; the foaming middle layer is of a layer structure of the foaming layer before foaming, the mass ratio of PVC powder to a plasticizer in the skin layer and the foaming middle layer is 0.842-1.333, and the foaming middle layer further comprises a foaming agent; the glue comprises bonding powder and a plasticizer, wherein the bonding powder comprises PVC powder and/or vinyl chloride-vinyl acetate copolymer PVC powder, and the mass ratio of the bonding powder to the plasticizer is 0.737-1.333;

Referring to fig. 2, in step S100, "sequentially coating the release paper to form the skin layer and the foamed intermediate layer" means that the skin layer raw material is coated on the release paper, and then the skin layer raw material and the release paper are sent to the first oven 3 by dragging the release paper, and the skin layer raw material is heated, so that the skin layer raw material is plasticized to form the skin layer; and then coating foaming layer raw materials on the surface layer (the side of the surface layer far away from the release paper, namely the inner side of the surface layer), continuously sending the surface layer and the foaming layer raw materials into a second drying oven 5 in a release paper dragging mode, and heating the foaming layer raw materials by the second drying oven 5 to plasticize the foaming layer raw materials to form a foaming interlayer. In the above process, each layer is attached to the release paper (the foaming middle layer is indirectly attached to the release paper), the forward force acts on the release paper due to the fact that the release paper is dragged, the epidermis layer (epidermis layer raw material) and the foaming middle layer (foaming layer raw material) are not directly stressed, and therefore the epidermis layer and the foaming middle layer cannot be stretched and deformed in the forming process of the epidermis layer and the foaming middle layer.

Similarly, the glue is coated on the foaming interlayer (the side of the foaming interlayer far from the surface layer) to form a glue layer, and the glue layer is indirectly attached to the release paper, so that in the process of foaming and plasticizing in the foaming oven 8 in step S200, the glue layer is also realized by dragging the release paper, and the glue layer is ensured not to be stretched and deformed (not to be calendered and deformed), so that compared with the existing calendering method, the stretching performance of the surface layer, the foaming layer and the glue base cloth layer (formed by plasticizing the glue layer and the base cloth, described in detail below) in the finally prepared artificial leather finished product is not influenced, and the finally obtained artificial leather finished product has better stretching performance compared with the artificial leather finished product obtained by the calendering method.

And, in the above process of preparing the finished artificial leather, because of adopting the coating method, the epidermal layer, the foaming layer and the glue base cloth layer are directly or indirectly carried on the release paper, and the position is transferred by dragging the release paper, in the process of dragging the release paper, because the release paper can not deform, the epidermal layer, the foaming layer and the glue base cloth layer on the release paper can not deform, thereby ensuring that the finally obtained finished artificial leather has better tensile property compared with the finished artificial leather prepared by the calendering method.

In step S100, "the mass ratio of the PVC powder to the plasticizer in the skin layer and the foamed intermediate layer is 0.842 to 1.333", and the mass ratio is, for example, 0.842, 0.878, 0.925, 0.974, 1.026, 1.114, 1.278, or 1.333. As mentioned above, the skin layer is formed by plasticizing the skin layer raw material, the foaming layer is formed by plasticizing and foaming the foaming layer raw material (see below in detail), the stretching properties of the skin layer and the foaming layer are mainly affected by the ratio of the PVC powder to the plasticizer, within a certain range, the higher the ratio of the plasticizer to the PVC powder is, the better the stretching properties of the skin layer and the foaming layer are, in the invention, the mass ratio of the PVC powder to the plasticizer in the skin layer and the foaming layer is as low as 0.842, so as to maximally improve the ratio of the plasticizer, improve the stretching properties of the skin layer and the foaming layer, and finally improve the stretching properties of the finished artificial leather.

Specifically, the skin layer (skin layer raw material) includes, in parts by mass: 80-100 parts of PVC powder, such as 80 parts, 85 parts, 90 parts, 93 parts, 97 parts or 100 parts and the like; 75-95 parts of plasticizer, such as 75 parts, 80 parts, 90 parts or 95 parts, etc.; 5-8 parts of inorganic filler, such as 5 parts, 6 parts, 7 parts or 8 parts; 2-5 parts of stabilizer, such as 2 parts, 3 parts, 4 parts or 5 parts, etc.; 3-10 parts of color paste, for example, 3 parts, 5 parts, 7 parts, 9 parts or 10 parts.

The preparation method of the epidermal layer raw material comprises the following steps:

adding the plasticizer at a stirring speed of 400-700rpm, such as 400rpm, 500rpm, 600rpm or 700 rpm;

adding PVC powder, inorganic filler and stabilizer, and stirring at 1000-1400rpm for 30-40min to obtain primary skin material; wherein, the stirring speed is 1000rpm, 1100rpm, 1200rpm, 1300rpm or 1400rpm, etc., and the stirring time is 30min, 32min, 35min, 37min or 40min, etc.;

adding the color paste into the primary epidermis raw material, stirring and defoaming at the stirring speed of 500-800rpm for 30-40min to obtain the epidermis raw material; the stirring speed is, for example, 500rpm, 600rpm, 700rpm, 800rpm, or the like, and the stirring and defoaming time period is, for example, 30min, 32min, 35min, 37min, or 40 min.

The foaming layer (foaming middle layer or foaming layer raw material) comprises the following components in parts by mass: 80-100 parts of PVC powder, such as 80 parts, 85 parts, 90 parts, 93 parts, 97 parts or 100 parts and the like; 75-95 parts of plasticizer, such as 75 parts, 80 parts, 90 parts or 95 parts; 5-8 parts of inorganic filler, such as 5 parts, 6 parts, 7 parts or 8 parts; 2-5 parts of stabilizer, such as 2 parts, 3 parts, 4 parts or 5 parts; 1 to 2 parts of a blowing agent, for example, 1 part or 2 parts.

The preparation method of the foaming layer raw material comprises the following steps:

adding PVC powder, inorganic filler, stabilizer and foaming agent, and stirring at the stirring speed of 1000-1400rpm for 20-50min to obtain the foaming layer raw material; the stirring speed is, for example, 1000rpm, 1100rpm, 1200rpm, 1300rpm, 1400rpm or the like, and the stirring time is, for example, 20min, 30min, 35min, 40min, 45min, 50min or the like.

In step S100, the glue comprises a bonding powder and a plasticizer, wherein the bonding powder comprises PVC powder and/or vinyl chloride-vinyl acetate copolymer PVC powder, in the finished artificial leather product, the glue functions to bond the base cloth and the foaming layer together, the substance playing a role in viscosity in the glue is the bonding powder, that is, the higher the mass ratio of the bonding powder to the plasticizer is, the higher the viscosity of the glue is, but the viscosity of the glue affects the process of glue coating to form a glue layer, and the glue is too high, which causes the glue to be difficult to extract and uniformly coat on the foaming interlayer, the viscosity of the glue is within the range of 4500-1.333 by controlling the mass ratio of the bonding powder to the plasticizer to be, for example, 0.737, 0.8, 0.85, 0.92, 1.05, 1.15, 1.23, 1.3 or 1.333, the viscosity of the glue is 4500-cps, the viscosity of the glue is, for example, 4500cps, 4600cps, 4700cps, 4900 or 5000cps, or the like, so that the larger the viscosity of the glue layer can also meet the requirement of the higher the viscosity of the finished artificial leather when the finished artificial leather is coated with the normal adhesive layer coated with the foaming layer, the glue, the adhesive has a square g of the glue, and the finished artificial leather, the adhesive can be separated by using 70g of the glue, and the glue, thus the glue layer can be maximized, the glue can be 70g of the finished artificial leather, the glue is not only by using 70-75g of the normal adhesive layer, and the glue, the glue is achieved by using 70g of the normal adhesive layer, and the glue layer, and the normal adhesive of the glue layer of the glue is not only by using 70g of the glue.

The viscosity of the existing glue is in the range of 3000-4300cps, so that the coating mass of the glue per square meter on the foaming middle layer is 85-90g.

In the glue, the bonding powder comprises PVC powder and/or chloroethylene-vinyl acetate copolymer PVC powder, preferably, the bonding powder comprises PVC powder and chloroethylene-vinyl acetate copolymer PVC powder, the viscosity of the glue can be further enhanced by adding the chloroethylene-vinyl acetate copolymer PVC powder, but in practical application, the price of the chloroethylene-vinyl acetate copolymer PVC powder is higher than that of the PVC powder, so that the mass of the chloroethylene-vinyl acetate copolymer PVC powder accounts for 11-25% of the total mass of the bonding powder, and the accounting ratio is 11%, 13%, 16%, 19%, 21%, 23% or 25%, and the like, thereby meeting the requirements of cost and glue viscosity and finally controlling the viscosity of the glue within the range of 4500-5000 cps.

Specifically, the glue comprises the following components in parts by mass: 60-100 parts of PVC powder, such as 60 parts, 70 parts, 80 parts, 90 parts or 100 parts; 10-20 parts of vinyl chloride-vinyl acetate copolymer PVC powder, such as 10 parts, 12 parts, 15 parts, 18 parts or 20 parts; 75-95 parts of plasticizer, such as 75 parts, 80 parts, 85 parts, 90 parts or 95 parts; the inorganic filler is 5 to 8 parts, for example, 5 parts, 6 parts, 7 parts or 8 parts.

The preparation method of the glue comprises the following steps:

adding PVC powder, polyethylene-vinyl acetate copolymer PVC powder and inorganic filler, and stirring at a stirring speed of 1000-1400rpm for 30-40min to obtain glue; the stirring speed is, for example, 1000rpm, 1100rpm, 1200rpm, 1300rpm, 1400rpm, or the like, and the stirring time is, for example, 30min, 32min, 35min, 37min, or 40 min.

According to the invention, the mass ratio of the bonding powder to the plasticizer and the mass ratio of the PVC powder to the vinyl chloride-vinyl acetate copolymer PVC powder are controlled to ensure that the viscosity of the glue can reach 4500-5000cps, so that the bonding of the glue base cloth layer and the foaming layer can be realized only by coating 70-75g of glue per square meter, the bonding firmness between the glue base cloth layer and the foaming layer is ensured, the quality of the glue is reduced to the maximum extent, and the tensile property of the finished artificial leather is improved to the maximum extent.

In step S200, four sides of the fabric with stretch ability are selected as the base fabric, and since the stretch ability of the four sides of the fabric with stretch ability is significantly higher than that of the conventional fabric, the test shows that the four sides of the fabric with stretch ability have a longitudinal static stretch ratio of not less than 115%, such as 115%, 120%, 123%, 125% or 130%, and a lateral static stretch ratio of not less than 180%, such as 180%, 185%, 190%, 195%, 198%, 202% or 205%, and the like, a longitudinal tear force of not more than 15N, such as 10N, 12N, 13N or 15N, a lateral tear force of not more than 15N, such as 10N, 12N, 13N or 15N, and the like, a tensile force required for longitudinally breaking the fabric per cm width is 34 to 38N, such as 34N, 35N, 36N, 37N or 38N, and the like, and a tensile force required for laterally breaking the fabric per cm width is 30 to 34N, such as 30N, 31N, 32N, 33N or 34N, and the like; the thickness of the conventional fabric is 0.6-0.7mm, the longitudinal static stretching rate of the conventional fabric is not more than 80%, the transverse static stretching rate of the conventional fabric is not more than 100%, the longitudinal tearing force of the conventional fabric is 25-30N, the transverse tearing force of the conventional fabric is 22-26N, the pulling force required for longitudinally breaking the conventional fabric with the width of each centimeter is 57-63N, and the pulling force required for transversely breaking the conventional fabric with the width of each centimeter is 54-58N.

The test results of static tension, tear strength, and force required to break the fabric per cm width were obtained for the four-sided stretch fabric and the conventional fabric, respectively, as shown in the following table.

Watch 1

In the first table, MD is the longitudinal direction of the fabric and CD is the transverse direction of the fabric.

Static stretch is to cut the fabric into 80 x 250mm samples and then measure the stretch of the samples by hanging a 10kg weight for 10 min.

Tear strength refers to the force required to cut an opening in a fabric and tear the fabric along the opening.

The "fabric having a width per cm" in the case of the force to stretch and cut the fabric having a width per cm is 1cm in the width perpendicular to the stretching direction, for example, 36N in the case of a force to stretch and cut the fabric having a stretching ability per cm on four sides in the MD direction, and 36N in the case of a force to stretch and cut the fabric in the MD direction when the width in the CD direction of the fabric having a stretching ability on four sides is 1 cm.

As can be seen from table one, the four-sided fabric with stretching properties has better stretching properties, that is, the four-sided fabric with stretching properties and the conventional fabric with the same specification (same length and width) are respectively stretched, and when the same stretching ratio is achieved, the stretching force required by the four-sided fabric with stretching properties is much smaller than that required by the conventional fabric, so that the four-sided fabric with stretching properties is more easily stretched; and further, the artificial leather finished product prepared by taking the cloth with tensile property on four sides as the raw material has better tensile property.

In the finished artificial leather product, the tensile property of the finished artificial leather product is influenced by the tensile property of each layer of the finished artificial leather product, and the tensile property of the glue base cloth layer is influenced by the coating amount of the glue and the characteristics of the base cloth, so that the finished artificial leather product obtained by the method has better tensile property; further, as shown in table one, since the conventional base fabric has a static stretch ratio in the MD of 76% and a static stretch ratio in the CD of 90%, in a finished artificial product made of a conventional fabric as a raw material (hereinafter referred to as a "comparative finished artificial leather product" for convenience of description), the static stretch ratio in the MD and the static stretch ratio in the CD of the comparative finished artificial leather are affected by the conventional fabric, so that the static stretch ratio in the MD of the comparative finished artificial leather is approximately 22% to 35%, and the static stretch ratio in the CD is approximately 42% to 53%. The static stretching rate of the fabric with stretching properties on four sides in the MD direction is up to 123%, the static stretching rate of the fabric in the CD direction is up to 198%, so that the static stretching rate of the finished artificial leather in the MD direction can reach 46% -58%, and the static stretching rate of the finished artificial leather in the CD direction can reach 70% -90% in a finished artificial leather product prepared by taking the fabric with stretching properties on four sides as a raw material, so that the static stretching rate of the finished artificial leather product is far higher than that of a contrast finished artificial leather product, and the finished artificial leather product obtained by the invention is easier to stretch, namely the finished artificial leather product obtained by the invention has better stretching properties.

The tensile property is determined by applying a fixed tensile force to a measured object (the measured object can be a cloth or an artificial leather finished product) on the premise of setting the dimension specification, and testing the elongation of the measured object under the tensile force. The higher the elongation, the better the tensile properties are considered.

In step S200, after the base cloth is covered on the glue layer, since the glue belongs to a fluid, the glue can penetrate into the meshes (the meshes are holes and pores between the woven fibers) of the base cloth after the base cloth is covered on the glue layer; in addition, because the mass of the glue per square meter is only 70-75g, the glue can almost completely permeate into the meshes of the base cloth, so that the base cloth is directly attached to the foaming middle layer, an independent glue layer is prevented from being formed between the base cloth and the foaming layer, the tensile property of an artificial leather finished product is reduced, the glue completely permeates into the meshes of the base cloth, and the influence of the glue on the tensile property of the base cloth can be maximally reduced while the base cloth is ensured to be bonded with the foaming layer; then, the surface layer, the foaming interlayer, the glue layer and the base fabric are sent into a foaming oven 8 in a mode of dragging release paper, foaming agent in the foaming interlayer is foamed in the foaming oven 8, so that the foaming interlayer forms a foaming layer, the glue is plasticized and forms a glue base fabric layer with the base fabric, and the glue base fabric layer is bonded with the inner side of the foaming layer, so that the primary finished product of the artificial leather is obtained. In a similar way, due to the adoption of the mode of dragging the release paper, the glue base cloth layer is not directly stressed, so that the finally obtained artificial leather finished product has higher tensile property.

Referring to fig. 2, steps S100 and S200 can be realized by a set of artificial leather production system, and include release paper unwinding roll 1, first coating head 2, first oven 3, second coating head 4, second oven 5, third coating head 6, base fabric winding roll 7, foaming oven 8 and winding roll group in sequence from upstream to downstream, wherein the winding roll group includes release paper winding roll 10 and artificial leather winding roll 9. Specifically, the release paper is released by the release paper unwinding roller 1, the release paper sequentially passes through the first coating head 2, the first oven 3, the second coating head 4, the second oven 5, the third coating head 6, the base fabric winding roller 7 and the foaming oven 8 and is finally rotatably accommodated by the release paper winding roller 10, during work, the release paper winding roller 10 actively rotates to drag the release paper to move in the system, so that the raw material of the skin layer is coated on the release paper at the first coating head 2 and then dragged into the first oven 3 to be plasticized to form the skin layer, then the raw material of the foaming layer is coated on the skin layer through the second coating head 4 and then dragged into the second oven 5 to be plasticized to form the foaming middle layer, then the foaming middle layer is dragged to the third coating head 6 at the downstream, the glue is coated on the third coating head 6, the base fabric is released by the base fabric winding roller 7 at the downstream to cover the glue and then is dragged into the foaming oven 8, finally the primary finished artificial leather on the release paper is accommodated by the release roller 9, and the release paper is wound on the release roller 10.

In the above process, only drag from type paper through from type paper wind-up roll 10, therefore all layers on type paper can not receive the drag power yet to ensured that the primary finished product's of synthetic leather that finally obtains tensile properties does not receive the loss.

In the above process, the temperature in the first oven 3 is 160 to 180 ℃, for example, 160 ℃, 165 ℃, 168 ℃, 170 ℃, 172 ℃, 175 ℃, 178 ℃, 180 ℃, and the duration in the first oven 3 is 60 to 120 seconds, for example, 60 seconds, 70 seconds, 90 seconds, 100 seconds, 120 seconds, thereby plasticizing the skin layer raw material to form the skin layer. Preferably, the length of the first oven 3 is 30-40m, for example, 30m, 34 m, 37m or 40m, etc., and the raw skin layer material on the release paper is fed into the first oven 3 from one end of the first oven 3 by dragging the release paper (e.g., the release paper take-up roll 10 is rotated), moves in the first oven 3, and finally comes out from the other end of the first oven 3, so that the duration of the raw skin layer material in the first oven 3 can be ensured by controlling the moving speed of the release paper. In other embodiments, the first oven 3 is an open-close type oven, when the skin layer raw material is plasticized, the first oven 3 is opened, the release paper bearing the skin layer raw material is wholly transferred into the first oven 3, and then the first oven 3 is opened at a temperature of 160-180 ℃ for 60-120 seconds to obtain the skin layer; the way of plasticizing to form the skin layer is not limited to the use of an oven, and any way of ensuring that a heating time of 60 to 120 seconds, a temperature of 160 to 180 ℃ can be provided, such as infrared heating, etc., is possible.

The foaming layer raw material is plasticized by the second oven 5 to form a foaming middle layer, the temperature range and the duration range of the second oven 5 are the same as those of the first oven 3, and the length range of the second oven 5 can be the same as or different from that of the first oven 3. The method for plasticizing the raw material of the foamed layer to form the foamed intermediate layer is not limited to the method of using an oven, and any method can be used as long as the heating time lasting for 60 to 120 seconds and the temperature of 160 to 180 ℃, for example, infrared heating and the like can be provided.

In the step S200, the base cloth, the glue layer, the foaming intermediate layer and the skin layer are sent to a foaming oven 8 for foaming and plasticizing, and the temperature in the foaming oven 8 is 190-210 ℃, for example 190 ℃, 195 ℃, 200 ℃, 205 ℃ or 210 ℃; the foaming plasticizing time is 120 to 180 seconds, for example 120 seconds, 130 seconds, 140 seconds, 150 seconds, 160 seconds, 170 seconds or 180 seconds. And foaming the foaming agent in the foaming intermediate layer in the foaming oven 8 at the temperature of 190-210 ℃ so as to change the foaming intermediate layer into a foaming layer, plasticizing the glue in the foaming oven 8 and forming a glue base cloth layer together with the base cloth, and simultaneously bonding the glue base cloth layer with the foaming layer in the plasticizing process. At this time, the laminated glue base cloth layer, the foaming layer and the surface layer can be obtained, and all the layers are plasticized.

In step S300, the surface treatment agent layer includes a base coat layer and a top coat layer, and the corresponding surface treatment agent includes a base coat material and a top coat material.

Specifically, the primer coating raw materials comprise the following components in percentage by mass: 100 parts of acrylic surface treating agent and 5-8 parts of cross-linking agent, wherein the cross-linking agent is 5 parts, 6 parts, 7 parts or 8 parts.

The top coating raw material comprises the following components in percentage by mass: 80-100 parts of polyurethane-forming treating agent, such as 80 parts, 85 parts, 90 parts, 95 parts or 100 parts; 3-8 parts of hand feeling agent, such as 3 parts, 5 parts, 7 parts or 8 parts; 0.2 to 0.5 parts of defoaming agent, for example, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts and the like; 1-4 parts of cross-linking agent, such as 1 part, 2 parts, 3 parts or 4 parts; 1-2 parts of leveling agent, such as 1 part or 2 parts; 30-50 parts of deionized water, such as 30 parts, 35 parts, 40 parts, 45 parts or 50 parts and the like.

The preparation method of the base coat raw material comprises the following steps: the acrylic type surface treatment agent and the crosslinking agent are mixed and stirred at a stirring speed of 400 to 800rpm, for example, 400rpm, 500rpm, 600rpm, 700rpm, 800rpm, or the like, to form the undercoating material.

The preparation method of the top coating raw material comprises the following steps: and mixing and stirring the polyurethane type treating agent, the hand feeling agent, the defoaming agent, the crosslinking agent, the leveling agent and the deionized water at a stirring speed of 400-1200rpm for 10-40min to obtain the top coating raw material. Wherein the stirring speed is, for example, 400rpm, 600rpm, 800rpm, 1000rpm, 1200rpm, or the like; the mixing and stirring time is 10min, 20min, 30min or 40 min.

In one embodiment, step S300 includes the steps of:

and S310, printing the base coating raw material on the surface (the outer side of the surface layer) of the surface layer far away from the foaming layer through a hexagonal wheel or a mesh wheel, and drying to form the base coating. Wherein the drying temperature is 100-120 deg.C, such as 100 deg.C, 105 deg.C, 110 deg.C, 115 deg.C or 120 deg.C, and the drying time is 120-180 seconds, such as 120 seconds, 130 seconds, 140 seconds, 150 seconds, 160 seconds, 170 seconds or 180 seconds.

And S320, printing the top coating raw material on the surface (the outer side of the base coating) of the base coating far away from the surface layer through a line wheel, and drying to form the top coating. Wherein the drying temperature is 100-120 deg.C, such as 100 deg.C, 105 deg.C, 110 deg.C, 115 deg.C or 120 deg.C, and the drying time is 120-180 seconds, such as 120 seconds, 130 seconds, 140 seconds, 150 seconds, 160 seconds, 170 seconds or 180 seconds.

In step S310, the "drying" may be performed by using an oven with a temperature of 100-120 ℃, or other heating methods, such as infrared heating, etc., may be used, as long as the drying temperature of 100-120 ℃ is ensured.

Similarly, the "drying" in step S320 is the same as the "drying" in step S310.

The number of the "hexagonal wheel or the mesh wheel" in the step S310 is preferably 100 to 120 meshes, for example, 100 meshes, 110 meshes, 120 meshes, or the like; the 'wire wheel' in the step S320 is a 133MF wire wheel, and can also be replaced by an 80-mesh wheel or an 80-mesh hexagonal wheel.

In step S400, the term "non-squeezing vacuum pattern suction" means that the outer side of the semi-finished artificial leather (the side away from the glue base fabric layer) is attached to the adsorption part of the vacuum pattern suction machine, a negative pressure is formed on the adsorption part, and the adsorption part has a concave-convex pattern, only the outer side of the semi-finished artificial leather is attached to the adsorption part, and the inner side of the semi-finished artificial leather is not in contact with any object, so that only the outer side of the semi-finished artificial leather is subjected to the adsorption force of the vacuum pattern suction machine except the self-gravity of the semi-finished artificial leather, so that the outer side of the semi-finished artificial leather forms a pattern matching the pattern on the adsorption part. At non-extrusion vacuum line absorption in-process, the synthetic leather semi-manufactured goods can not receive the extrusion force to make glue base cloth layer and foaming layer can not imbed each other, thereby ensure that the off-the-shelf tensile properties of synthetic leather that finally obtains can not reduce because of preparing the decorative pattern, ensure that the synthetic leather finished product has high tensile properties. The term "embedded in" means that some of the foamed layer enters the meshes of the base fabric.

Mode that the mode that forms the decorative pattern on the current synthetic leather finished product is mostly steel roller knurling's mode, "steel roller knurling" does, heat synthetic leather semi-manufactured goods earlier, use through a steel roller and a rubber roller cooperation, wherein the steel roller take on concave-convex decorative pattern on the surface, form the extrusion mouth between rubber roller and the steel roller, the width (the thickness direction that corresponds synthetic leather semi-manufactured goods) of this extrusion mouth is less than synthetic leather semi-manufactured goods's thickness, synthetic leather semi-manufactured goods passes the extrusion mouth, through the extrusion between rubber roller and the steel roller, make and form the decorative pattern on synthetic leather semi-manufactured goods's the surface. However, due to the extrusion of the rubber roller and the steel roller, the glue base fabric layer and the foaming layer are embedded into each other (on the cross-sectional view of the finished artificial leather product, the boundary line between the glue base fabric layer and the foaming layer is a wavy line or a zigzag line). Specifically, there are numerous meshs on the base cloth, when forming the glue base cloth layer, the meshs are filled by glue, and after the heating of synthetic leather semi-manufactured goods, glue and foaming layer all can become soft, and under the external extrusion (the extrusion of rubber roller and steel roller), the foaming layer can be crowded into the meshs of base cloth to the phenomenon of glue base cloth layer and the mutual embedding of foaming layer appears, finally leads to the off-the-shelf tensile properties's of synthetic leather reduction.

Certainly, the prior art also has a vacuum grain sucking mode by using a vacuum grain sucking machine, but the prior vacuum grain sucking machine is provided with a transfer roller and a rubber roller (such as Chinese publication No. CN 205387639U), the transfer roller and the rubber roller can extrude the semi-finished artificial leather, so that the phenomenon that a glue base cloth layer and a foaming layer are embedded into each other can also occur, and the tensile property of the finished artificial leather is finally reduced.

In addition, the depth of pattern is less than or equal to surface treatment agent layer the epidermal layer and the thickness sum of foaming layer, promptly, inhale the in-process of line at non-extrusion vacuum and can not cause the influence to the glue base cloth layer, ensure that glue base cloth layer and foaming layer can not imbed each other, ensure the tensile properties of synthetic leather finished product.

As described above, in the raw material for the skin layer (the raw material for the skin layer) and the raw material for the foamed intermediate layer (the raw material for the foamed layer), the smaller the ratio of PVC powder to the plasticizer, the better the stretch properties of the skin layer and the foamed layer, and the finished artificial leather according to the present invention is substantially PVC artificial leather, and therefore PVC powder is one of the main components for producing the finished artificial leather, and the present invention maximally increases the amount of the plasticizer to enhance the stretch properties of the skin layer and the foamed layer while ensuring the formation of the finished artificial leather, thereby finally improving the stretch properties of the finished artificial leather.

Specifically, the thickness of the skin layer is 0.2 to 0.3mm, for example, 0.2mm, 0.25mm, 0.3mm or the like; the thickness of the foamed layer is 0.3 to 0.4mm, for example, 0.3mm, 0.35mm, 0.4mm, or the like. The thinner the thickness of the skin layer and the thickness of the foamed layer, the better the tensile properties of the skin layer and the foamed layer. Preferably, the skin layer has a thickness of 0.2mm and the foam layer has a thickness of 0.3mm.

As mentioned above, the invention can obtain glue with the viscosity of 4500-5000cps by controlling the proportion between bonding powder (PVC powder and polyethylene-vinyl acetate copolymer PVC powder) and plasticizer and the proportion between PVC powder and polyethylene-vinyl acetate copolymer PVC powder, so that the bonding purpose can be realized by only coating 70-75g of glue per square meter, thereby reducing the use amount of glue and improving the tensile property of finished artificial leather products.

The four-sided fabric having tensile properties has a thickness of 0.35 to 0.45mm, such as 0.35mm, 0.37mm, 0.40mm, 0.43mm, or 0.45mm, etc., such that the glue base layer has a thickness of 0.35 to 0.45mm, such as 0.35mm, 0.37mm, 0.40mm, 0.43mm, or 0.45mm, etc. The mass of the glue per square meter is 70-75g, so when the base cloth is covered on the glue, the glue can be absorbed by the base cloth, namely the glue is blended into the base cloth, so that the glue and the base cloth are integrated, the thickness of the finally obtained glue base cloth layer is approximately equal to that of the base cloth layer, in the cross-sectional view of the artificial leather finished product, discontinuous glue (the glue is plasticized) exists between the base cloth and the foaming layer, but the glue thickness is not more than 10 mu m at the position where the glue exists.

Preferably, the mass of the vinyl acetate in the vinyl chloride-vinyl acetate copolymer PVC powder is 3-5% of the total mass of the vinyl chloride-vinyl acetate copolymer PVC powder, and the higher the proportion of the vinyl acetate in the vinyl chloride-vinyl acetate copolymer PVC powder, the higher the viscosity of the glue, and preferably, the mass of the vinyl acetate in the vinyl chloride-vinyl acetate copolymer PVC powder is 5% of the total mass of the vinyl chloride-vinyl acetate copolymer PVC powder, so that when a glue with a specific viscosity is obtained (for example, the viscosity of the glue is 5000 cps), the dosage of the vinyl chloride-vinyl acetate copolymer PVC powder is maximally reduced and the dosage of the PVC powder is increased.

The invention selects cloth with tensile property on four sides as base cloth, the cloth is terylene cloth, which is specifically woven by 60-90D terylene fiber, and the mass of the cloth per square meter is controlled to be 80-90g, such as 80g, 82g, 85g, 87g or 90g, etc. Compared with fabrics made of other materials, the terylene fabric has better tensile property, is woven by 60-90D terylene fibers, such as 60D, 65D, 70D, 75D, 80D, 85D or 90D, so that the fabric has lighter weight and sparser fibers, and has longitudinal static tensile rate not less than 115%, transverse static tensile rate not less than 180%, longitudinal tearing force not more than 15N, transverse tearing force not more than 15N, tensile force required for longitudinally breaking the fabric per centimeter in width of 34-38N, and tensile force required for transversely breaking the fabric per centimeter in width of 30-34N, thereby ensuring the tensile property of the finished artificial leather.

Preferably, in step S400, the pattern depth of the vacuum embosser is less than or equal to the sum of the thicknesses of the surface treatment agent layer and the skin layer; the vacuum degree of the vacuum embossing is 0.03-0.06MPa, such as 0.03MPa, 0.04MPa, 0.05MPa or 0.06MPa, and the duration of the vacuum embossing is 20-30s, such as 20s, 22s, 25s, 27s or 30s. According to the invention, by controlling the vacuum degree, the semi-finished artificial leather can be fully attached to the patterns on the vacuum pattern suction machine during pattern suction, sufficient suction force is provided and the vacuum pattern suction time is matched to enable the patterns to be formed on the semi-finished artificial leather, in the process of forming the patterns, the glue base cloth layer and even the foaming layer can not be changed in any shape, and the glue base cloth layer or the base cloth can not form bulges to one side of the foaming layer along with the bulges of the patterns.

Preferably, the skin layer is a layer of a polymer,

Because the depth of the patterns of the vacuum grain absorbing machine is less than or equal to the thickness of the surface treating agent layer and the surface skin layer, when the non-extrusion vacuum grain absorbing is carried out, the vacuum grain absorbing machine only affects the surface treating agent layer and the surface skin layer at most, and does not affect the foaming layer. Because the difference of PVC powder and plasticizer ratio in the epidermal layer raw materials leads to the epidermal layer hardness also to produce the change, specifically, the quality ratio of PVC powder and plasticizer is big more, then the epidermal layer is harder, tensile properties is lower, otherwise, the epidermal layer is soft more, tensile properties is better, and when the line is inhaled in the vacuum, if vacuum numerical value is too high, and the epidermal layer is soft again, can make the epidermal layer adhesion inhale the line machine in the vacuum to influence the off-the-shelf yields of synthetic leather. According to the invention, the vacuum degree during vacuum grain suction is determined according to the numerical value of the mass ratio of the PVC powder to the plasticizer in the surface layer, so that patterns can be formed on the semi-finished artificial leather, the phenomenon that the surface layer is not adhered to a vacuum grain suction machine is avoided, and the yield of finished artificial leather is improved.

Preferably, the thickness of the skin layer is 0.2 to 0.3mm, and the thickness of the surface treatment agent layer is 4 to 16 μm, for example, 4 μm, 8 μm, 12 μm, 14 μm, 16 μm, or the like;

in the step S400, the pattern depth of the vacuum embosser is 10 to 50 μm, for example, 10 μm, 20 μm, 30 μm, 40 μm, or 50 μm.

The thickness of the base coat is 2-8 μm and the thickness of the top coat is 2-8 μm. Thus, the pattern on the finished artificial leather is completely formed by the top coat, the base coat and part of the skin layer.

Preferably, in the step S400, the artificial leather semi-finished product is first heated by infrared rays until the temperature of the outer surface reaches 140 to 180 ℃, for example, 140 ℃, 150 ℃,160 ℃, 170 ℃ or 180 ℃, and then a vacuum embossing machine is used to perform non-extrusion vacuum embossing on the outer surface of the artificial leather. The outer surface refers to a plane on which one side of the semi-finished artificial leather far away from the glue base cloth layer is located, when the temperature of the outer surface reaches 140-180 ℃, the outer surface of the semi-finished artificial leather becomes soft, so that non-extrusion vacuum grain suction is conveniently carried out on the outer surface of the semi-finished artificial leather through a vacuum grain suction machine in the follow-up process.

The finished artificial leather obtained by the method is tested, the force required for longitudinally breaking the finished artificial leather with the width of each centimeter is 60-65N, the force required for transversely breaking the finished artificial leather with the width of each centimeter is 38-45N, the longitudinal elongation at break is 76-85%, the transverse elongation at break is 230-255%, the longitudinal static elongation can reach 46-58%, and the transverse static elongation can reach 70-90%.

In practical application, when an operator stretches a finished artificial leather product for coating, the finished artificial leather product is usually stretched by 5% -10%, taking 5% stretching as an example, the force required by 5% longitudinal stretching of the finished artificial leather product of the invention is 12-18N, and the force required by 5% transverse stretching of the finished artificial leather product is 13-19N. The force required by the prior artificial leather for stretching 5 percent in the longitudinal direction is 25-38N, and the force required by the prior artificial leather for stretching 5 percent in the transverse direction is 25-38N. Obviously, the finished artificial leather product of the invention is easier to stretch. Therefore, the fatigue of operators can be reduced, and the coating efficiency of the operators is improved.

The stabilizer can be calcium zinc stabilizer, the plasticizer can be phthalate, the inorganic filler can be calcium carbonate, and the polymerization degree of the PVC powder is preferably between 1000 and 1300.

Specific examples of the method for producing artificial leather having stretchability are given below:

example one

S100, taking release paper as a carrier, sequentially coating the release paper to form a skin layer and a foaming middle layer, and coating a glue layer on the foaming middle layer according to the mass of 70-75g per square meter.

The skin layer comprises 100 parts of PVC powder, 75 parts of plasticizer, 5 parts of inorganic filler, 2 parts of stabilizer and 4 parts of color paste.

The foaming interlayer comprises 100 parts of PVC powder, 75 parts of plasticizer, 5 parts of inorganic filler, 2 parts of stabilizer and 1 part of foaming agent.

The glue comprises 80 parts of PVC powder, 20 parts of vinyl chloride-vinyl acetate copolymer PVC powder, 75 parts of plasticizer and 5 parts of inorganic filler.

S200, taking cloth with tensile property on four sides as base cloth, covering the base cloth on the glue layer, sending the base cloth into a foaming oven for foaming and plasticizing, so that a foaming agent in the foaming middle layer forms a foaming layer after foaming, and the base cloth and the glue form a glue base cloth layer and are bonded with the foaming layer.

S300, removing the release paper, printing a surface treating agent on the outer side of the surface layer, and drying to form a surface treating agent layer to obtain the artificial leather semi-finished product.

The surface treating agent comprises a bottom coating raw material and a top coating raw material.

The base coat comprises the following raw materials in parts by mass: 100 parts of acrylic surface treating agent and 8 parts of cross-linking agent.

The top coating raw material comprises the following components in parts by mass: 90 parts of polyurethane type treating agent, 5 parts of hand feeling agent, 0.2 part of defoaming agent, 3 parts of crosslinking agent, 1.5 parts of flatting agent and 30 parts of deionized water.

S400, carrying out infrared heating on the semi-finished artificial leather product, and then carrying out non-extrusion vacuum grain suction on the outer surface of the artificial leather by using a vacuum grain suction machine to obtain a finished artificial leather product I.

Example two

The two embodiments differ from the first embodiment in that:

85 parts of plasticizer, 8 parts of inorganic filler and 3 parts of stabilizer in the surface layer; 85 parts of plasticizer and 8 parts of inorganic filler in the foaming intermediate layer; 5 parts of hand feeling agent, 1.5 parts of flatting agent and 3 parts of cross-linking agent in the top coating raw material.

In example two, finished artificial leather product two was obtained.

EXAMPLE III

Example three phases differ from example one in that:

95 parts of plasticizer, 8 parts of inorganic filler and 3 parts of stabilizer in the raw material of the surface layer; 95 parts of plasticizer and 8 parts of inorganic filler in the foaming raw material; 5 parts of hand feeling agent, 1.5 parts of flatting agent and 3 parts of cross-linking agent in the top coating raw material.

In the third example, a third finished artificial leather product was obtained.

Comparative example 1

The difference between the first comparative example and the third example is that:

the base cloth is conventional base cloth, and the mass of the conventional base cloth per square meter is 120-130g.

Comparative example one a comparative finished artificial leather product one was obtained.

Comparative example No. two

The difference between the comparative example two and the example three is that:

the non-extrusion vacuum embossing is replaced by an iron roller embossing mode.

Comparative finished artificial leather product two obtained in comparative example two.

Comparative example No. three

The difference between the third comparative example and the third example is that:

the base cloth is conventional base cloth, and the mass of the conventional base cloth per square meter is 120-130g; the non-extrusion vacuum suction pattern is replaced by an iron roller embossing mode.

Comparative finished artificial leather third obtained in comparative example two.

Comparative example four (finished artificial leather manufactured by calendering)

The same glue, skin layer material and foaming layer material were used in the examples.

Coating the glue on the low-gram-weight base cloth by using a pasting machine to obtain an intermediate product I;

rolling the foaming layer raw material into a foaming material with the thickness of 0.2-0.3mm, and attaching the foaming material and the intermediate product I to obtain an intermediate product II;

rolling the skin layer raw material into a skin material with the thickness of 0.2-0.3mm, bonding the skin material with the intermediate product II, and then sending the skin material into a high-temperature foaming furnace for high-temperature foaming to obtain a rolled semi-finished product;

and printing a bottom coating and a top coating on the calendered semi-finished product in the same way as the three phases of the embodiment, and forming patterns on the calendered semi-finished product in a non-extrusion vacuum pattern absorption way to obtain a fourth contrast artificial leather product.

Respectively testing the static tensile rate, the 5% circular modulus, the tensile strength and the elongation at break of the first finished artificial leather product, the second finished artificial leather product, the third finished artificial leather product, the first comparative artificial leather product, the second comparative artificial leather product, the third comparative artificial leather product and the fourth comparative artificial leather product, wherein the test results are shown in the following table 2:

TABLE 2

In table 2, MD is the longitudinal direction of the test article and CD is the transverse direction of the test article.

The static tensile test was performed by cutting the test object into a sample of 80 × 250mm, and then measuring the tensile of the sample by hanging a 10kg weight for 10 min. And when measuring the MD tensile rate of the sample, the longitudinal length of the sample is 250mm, and the transverse length of the sample is 80mm; the CD stretch of the sample was measured, and the sample had a transverse length of 250mm and a longitudinal length of 80mm.

The test of 5% circular modulus cuts the measured object into the circular sample of diameter 300mm, test on the stretcher, the longitudinal or horizontal both ends of sample are cliied respectively to two anchor clamps of stretcher, the width of two anchor clamps is 25.4mm, and make and keep 200 mm's interval between two anchor clamps, the anchor clamps outside (keep away from the central zone of sample) stretch 10mm, record the pulling force that the stretcher was exerted, under this test artificial leather finished product longitudinal stretching 5% required strength is 12-18N, transverse stretching 5% required strength is 13-19N, the longitudinal stretching 5% required strength of contrast synthetic leather finished product is 25-38N, transverse stretching 5% required strength is 25-38N.

In table 2, the first finished artificial leather product has a lower stretch property than that of the second finished artificial leather product, and the second finished artificial leather product has a lower stretch property than that of the third finished artificial leather product, and it can be seen that, in a certain range, the higher the ratio of the plasticizer to the PVC powder is, the better the stretch properties of the skin layer and the foamed layer are, so that the corresponding finished artificial leather product has a better stretch property. In addition, from the test results of the finished artificial leather product and the comparative finished artificial leather product, the finished artificial leather product obtained by adopting the method for preparing the artificial leather, namely the coating method, the cloth with low gram weight as the base cloth and the non-extrusion vacuum pattern absorption has better tensile property.

The finished artificial leather prepared by the artificial leather preparation method has the advantages that the longitudinal static stretching rate is 46-58%, the transverse static stretching rate is 70-90%, the force required by the longitudinal stretching of 5% is 12-18N, the force required by the transverse stretching of 5% is 13-19N, the force required by the longitudinal stretch breaking of the finished artificial leather per centimeter in width is 60-65N (the transverse width of the finished artificial leather is 1cm, the force required by the longitudinal stretch breaking of the finished artificial leather is 60-65N), the force required by the transverse stretch breaking of the finished artificial leather per centimeter in width is 38-45N (the longitudinal width of the finished artificial leather is 1cm, the transverse stretch breaking of the finished artificial leather is 60-65N), the longitudinal breaking elongation is 76-85%, and the transverse breaking elongation is 230-255%.

Referring to fig. 3, the present invention also provides an artificial leather having stretchability, comprising a glue base layer 11, a coating-formed foam layer 12, a coating-formed skin layer 13, and a surface treatment agent layer, which are sequentially laminated, wherein,

the glue base cloth layer 11 comprises base cloth and glue, and the base cloth is cloth with tensile properties on four sides; the glue base cloth layer 11 is bonded with the foaming layer 12, and the glue base cloth layer 11 and the foaming layer 12 are not embedded into each other;

forming a pattern on the layer structure from the surface treating agent layer to the foaming layer 12 in a non-extrusion vacuum pattern absorption mode;

under a static tensile test, the longitudinal static tensile rate of the artificial leather is 46-58%, and the transverse static tensile rate is 70-90%;

under a circular modulus test, the force required by the artificial leather for stretching 5 percent in the longitudinal direction is 12-18N, and the force required by stretching 5 percent in the transverse direction is 13-19N;

The artificial leather has high tensile property, and when the artificial leather is applied, an operator can stretch the artificial leather more laborsavingly for coating, so that the working strength of the operator is reduced, the working efficiency is improved, and the coating yield is improved.

the longitudinal static stretching rate of the fabric is not less than 115%, the transverse static stretching rate is not less than 180%, the longitudinal tearing force is not more than 15N, the transverse tearing force is not more than 15N, the pulling force required for longitudinally breaking the fabric with the width of each centimeter is 34-38N, and the pulling force required for transversely breaking the fabric with the width of each centimeter is 30-34N.

Preferably, in the raw materials of the skin layer and the foaming layer: 80-100 parts of PVC powder and 75-95 parts of plasticizer; the sum of the thicknesses of the skin layer and the foaming layer is 0.5-0.7mm. The stretching performance of the surface layer and the foaming layer is mainly influenced by the proportion of the PVC powder and the plasticizer, the higher the ratio of the plasticizer to the PVC powder is in a certain range, the better the stretching performance of the surface layer and the foaming layer is, and the mass ratio of the PVC powder to the plasticizer in the surface layer and the foaming layer is as low as 0.842, so that the ratio of the plasticizer is maximally improved, the stretching performance of the surface layer and the foaming layer is improved, and the stretching performance of the artificial leather is finally improved.

Preferably, the glue comprises the following raw materials: 60-100 parts of PVC powder, 10-20 parts of polyethylene-vinyl acetate copolymer PVC powder and 75-95 parts of plasticizer; the thickness of the base cloth is 0.35-0.45mm, and the thickness of the glue between the base cloth layer and the foaming layer is less than or equal to 10 micrometers. The proportion of the glue enables the viscosity of the glue to reach 4500-5000cps, the using amount of the glue per square meter can be as low as 70-75g, the thickness of the glue base cloth layer is basically equal to that of the base cloth, meanwhile, the thickness of the glue base cloth layer and the foaming layer support is controlled within 10 microns (most of the glue is not present between the glue base cloth layer and the foaming layer support, and the thickness of the part where the glue is present is also within 10 microns), and therefore the tensile property of the artificial leather is ensured.

The invention also provides an automobile interior, which comprises the artificial leather with stretchability. The artificial leather has high tensile properties, and is thus particularly suitable for use as automotive interiors.

Preferably, the automotive interior is a door trim, a door center panel trim, a door armrest trim, a dashboard trim, and/or a center console trim. Because of its high stretch properties, artificial leather is particularly suitable for covering shaped articles with elongated sharp corners on automobiles, such as for covering door tops, door center panels, door armrests, instrument panels, and center control armrests. Operating personnel only need exert less strength to artificial leather, alright stretch the synthetic leather to the convenience is wrapped the interior trim that needs the cladding, reduces operating personnel's tired sense, improves the cladding effect, increases the yields.

It will be understood that the embodiments described above are illustrative only and not restrictive, and that various obvious and equivalent modifications and substitutions for details described herein may be made by those skilled in the art without departing from the basic principles of the invention.

Claims

1. A method for preparing artificial leather having stretchability, characterized by comprising the steps of:

s200, taking cloth with tensile properties on four sides as base cloth, covering the base cloth on the glue layer, sending the base cloth into a foaming oven for foaming and plasticizing to enable the foaming middle layer to be foamed to form a foaming layer, and simultaneously forming a glue base cloth layer by the glue and the base cloth and bonding the glue base cloth layer with the foaming layer;

the longitudinal static stretching rate of the fabric is not less than 115%, the transverse static stretching rate of the fabric is not less than 180%, the longitudinal tearing force is not more than 15N, the transverse tearing force is not more than 15N, the pulling force required for longitudinally breaking the fabric per centimeter in width is 34-38N, and the pulling force required for transversely breaking the fabric per centimeter in width is 30-34N;

s400, heating the artificial leather semi-finished product; and then, carrying out non-extrusion vacuum grain absorption on the outer surface of the semi-finished artificial leather by using a vacuum grain absorption machine to obtain the finished artificial leather, wherein the depth of the pattern of the vacuum grain absorption machine is less than or equal to the sum of the thicknesses of the surface treating agent layer, the surface layer and the foaming layer.

2. The production method according to claim 1, wherein, in the raw materials of the skin layer and the foamed intermediate layer: 80-100 parts of PVC powder and 75-95 parts of plasticizer; the sum of the thicknesses of the skin layer and the foaming layer is 0.5-0.7mm.

3. The preparation method of claim 1, wherein the glue comprises the following raw materials: 60-100 parts of PVC powder, 10-20 parts of polyethylene-vinyl acetate copolymer PVC powder and 75-95 parts of plasticizer; the thickness of the base cloth is 0.35-0.45mm, and the thickness of the glue between the base cloth layer and the foaming layer is less than or equal to 10 mu m.

4. The preparation method of claim 1, wherein the mass ratio of the vinyl acetate in the vinyl chloride-vinyl acetate copolymer PVC powder is 3-5%.

5. The manufacturing method according to any one of claims 1 to 4, wherein the four-sided fabric having tensile properties has a mass per square meter of 80 to 90g, and is woven using 60 to 90D polyester fibers.

6. The production method according to any one of claims 1 to 5, wherein in step S400, the pattern depth of the vacuum embosser is less than or equal to the sum of the thicknesses of the surface treatment agent layer and the skin layer; the vacuum degree of the vacuum line suction is 0.03-0.06Mpa, and the time of the vacuum line suction is 20-30s.

7. The production method according to claim 6, wherein in the skin layer,

8. The production method according to claim 6, wherein the skin layer has a thickness of 0.2 to 0.3mm, and the surface treatment agent layer has a thickness of 4 to 16 μm;

9. The preparation method according to claim 6, wherein in the step S400, the semi-finished product of the artificial leather is heated in infrared until the temperature of the outer surface reaches 140-180 ℃, and then a vacuum grain sucking machine is used for non-extrusion vacuum grain sucking on the outer surface of the artificial leather.

10. An artificial leather having stretchability, comprising a glue base layer, a coating-molded foam layer, a coating-molded skin layer and a surface treatment agent layer, which are laminated in this order,

11. The artificial leather according to claim 10, wherein the mass per square meter of the cloth is 80-90g, and the cloth is woven by using 60-90D polyester fibers;

12. Artificial leather according to claim 10, wherein of the raw materials of said skin layer and said foamed layer: 80-100 parts of PVC powder and 75-95 parts of plasticizer; the sum of the thicknesses of the skin layer and the foaming layer is 0.5-0.7mm.

13. The artificial leather of claim 10, wherein the glue comprises, in the raw materials: 60-100 parts of PVC powder, 10-20 parts of polyethylene-vinyl acetate copolymer PVC powder and 75-95 parts of plasticizer; the thickness of the base cloth is 0.35-0.45mm, and the thickness of the glue between the glue base cloth layer and the foaming layer is less than or equal to 10 mu m.

14. The artificial leather according to claim 12, wherein the thickness of the skin layer is 0.2-0.3mm, and the thickness of the surface treatment agent layer is 4-16 μm; the depth of the patterns is 10-50 μm.

15. An automotive interior characterized by comprising the artificial leather having stretchability of any one of claims 10 to 14.

16. The automotive interior of claim 15, wherein the automotive interior is a door trim, a door center panel trim, a door armrest trim, a dashboard trim, and/or a center armrest trim.