Leather color processing technology

Abstract

The invention relates to the technical field of leather processing, and particularly discloses a leather color processing technology which comprises the following steps: step 1, base material transfer printing: preparing a leather base material and a transfer printing mold, coating UV glue on the transfer printing mold, placing the leather base material on the transfer printing mold, extruding through a roller to enable the UV glue to be attached to the leather base material, and transferring the UV glue on the transfer printing mold when the UV glue is transferred; attractive and changeable textures can be left on the leather base material, and the leather and the coating layer can achieve a better grafting effect. And 2, coating and coloring: putting the transferred leather base material into coating equipment, and carrying out optical coating, so as to form a plurality of layers of colored solid films on the surface of the leather base material. According to the present invention, the high wear resistance is provided, the product has the rich and colorful 2D and 3D stereo appearance texture patterns, the texture is good, the appearance is exquisite, and the optical texture color has the angle change color effect, and is not limited to the traditional printing spraying and other solid color effects.

Description

Technical Field

[0001] The invention relates to the technical field of leather processing, in particular to a leather color processing technology. Background Art

[0002] Leather is a kind of animal skin that has been denatured and is not easy to rot after physical and chemical processing such as depilation and tanning. Leather is composed of natural protein fibers tightly woven in three-dimensional space. Its surface has a special grain layer with natural grain and luster, and feels comfortable. Leather has good air permeability, superior durability, unique texture, easy maintenance, and strong plasticity. There are many types of leather. According to the source, it can be divided into animal leather and artificial leather; according to the tanning method, it can be divided into chrome tanned leather, vegetable tanned leather, oil tanned leather, etc.; according to the use, it can be divided into leather for shoes, leather for clothing, leather for furniture, etc. Leather is widely used in clothing, footwear, luggage, furniture, automotive interiors and other fields.

[0003] When coloring the leather materials of existing shoes, traditional silk screen printing ink or spraying is generally used, and a silk screen printer is used. However, this method is not environmentally friendly, has poor surface hardness and wear resistance, and the product has no 2D or 3D appearance and the optical texture is ordinary and not exquisite, which cannot meet market demand. Summary of the invention

[0004] In view of the defects of the above-mentioned prior art, the present invention provides a leather color processing technology with high wear resistance. The product has more colorful 2D and 3D stereoscopic appearance texture patterns, good texture, exquisite appearance, and optical texture color with angle-changing color effects, and is not limited to traditional solid color effects such as printing and spraying.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is:

[0006] The leather color processing technology includes the following steps:

[0007] The first step is substrate transfer. Prepare the leather substrate and transfer mold, apply UV glue on the transfer mold, place the leather substrate on the transfer mold, and squeeze the UV glue with the leather substrate through rollers. When transferring UV glue, in addition to leaving beautiful and varied textures on the leather substrate, it can also make the leather and the coating layer play a better grafting role;

[0008] The second step is coating and coloring. The transferred leather substrate is placed in the coating equipment for optical coating to form multiple layers of colored solid films on the surface of the leather substrate.

[0009] In the above description, preferably, the first step further includes surface treatment before the substrate transfer, and the surfaces of the leather substrate and the transfer mold are subjected to dust removal, oil removal, and drying treatments.

[0010] In the above description, preferably, the substrate transfer in the first step also includes a curing treatment, which is carried out in a UV drying tunnel and cured by an ultraviolet lamp. The energy of the ultraviolet lamp is set to 1800 joules, the wavelength is 365-420nm, and the irradiation time is 3-5 seconds.

[0011] In the above description, preferably, the first step of substrate transfer also includes preheating, and during preheating, the temperature is increased to 30-40°C.

[0012] In the above description, as a preferred embodiment, when the first step is to use UV transfer equipment to perform transfer work, the hardness of the UV glue is 45-55 Shore D.

[0013] In the above description, preferably, the coating equipment in the second step of coating and coloring is a thermal evaporation coating machine.

[0014] In the above description, preferably, the third step of inspection is included after the second step, in which the quality of the leather substrate after coating and coloring is inspected.

[0015] The beneficial effects of the present invention are as follows: a transfer mold and UV glue are used to perform texture transfer. When the UV glue is transferred, in addition to leaving beautiful and varied textures on the leather substrate, the leather and the coating layer can also be better grafted together. Optical coating is performed through coating equipment to form a multi-layer solid film with color on the surface of the leather substrate. The product has high wear resistance, and has more colorful 2D and 3D stereoscopic appearance texture patterns, good texture, exquisite appearance, and optical texture color with angle-changing color effects, rather than being limited to traditional solid color effects such as printing and spraying. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 : is a schematic diagram of a flow chart of an embodiment of the present invention; DETAILED DESCRIPTION

[0017] In order to more clearly explain the structural features, technical means and specific purposes and functions achieved by the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0018] Embodiment 1: Figure 1 As shown, the leather color processing process includes the following steps:

[0019] The first step is to prepare materials, substrates and transfer molds.

[0020] The second step is surface treatment, which involves dust removal, oil removal, and drying of the leather substrate and the transfer mold.

[0021] The third step is transfer printing. Prepare the leather substrate and transfer mold, apply UV glue on the transfer mold, place the leather substrate on the transfer mold, and make the UV glue fit the leather substrate through roller extrusion. Copy the texture on the transfer mold to the surface of the leather substrate to achieve texture transfer. When transferring UV glue, in addition to leaving beautiful and changeable textures on the leather substrate, it can also make the leather and the coating layer play a better grafting role. It should be noted that the temperature of the leather substrate has a great influence on the transfer effect. In low temperature seasons, the leather substrate needs to be preheated to increase its temperature to 30-40℃ to obtain better adhesion. At the same time, the hardness of UV glue is 45-55 Shao D, which solves the bending resistance, stretchability and cracking effects of the glue attached to the leather substrate, and has good surface hardness and wear resistance.

[0022] The fourth step is curing, which is carried out in a UV drying tunnel and cured by ultraviolet lamp. The energy of the ultraviolet lamp is set to 1800 joules, the wavelength is 365-420nm, and the irradiation time is 3-5 seconds;

[0023] The fifth step is coating and coloring. The transferred leather substrate is placed in the coating equipment. The coating equipment uses a thermal evaporation coating machine for optical coating. In the vacuum chamber, the raw materials to be formed into the film in the evaporation container are heated to make their atoms or molecules vaporize and escape from the surface to form a vapor flow, which is incident on the surface of the leather substrate to condense and form a solid film. By changing the material and its thickness and other characteristics, the interference of light is artificially controlled. The combined film stack film layer forms an optical color, so that a multi-layer solid film with color is formed on the surface of the leather substrate. The optical color is saturated, and the brightness is achieved by the optical film thickness required by the film layer thickness design. It has high wear resistance. The product has a more colorful 2D and 3D three-dimensional appearance texture pattern, good texture, exquisite appearance, and optical texture color with angle-changing color effect, rather than being limited to traditional printing and spraying and other solid color effects. The new process technology replaces printing and spraying ink coloring, and there is no wastewater and waste gas, which is more environmentally friendly.

[0024] The sixth step is to inspect the quality of the leather substrate after coating and coloring.

[0025] It should be noted that the samples of footwear materials in this embodiment have passed the SGS test report, including the tested 168-hour aging performance, damp heat aging at 70°C and 100% relative humidity, footwear yellowing resistance (HG / T3689-2014) method B (ultraviolet lamp method), experimental conditions 30W ultraviolet lamp for 3 hours, color fastness to migration to polymer materials (ISO15701:2015), and low-temperature flexion performance of upper materials (QB / T2224-2012).

[0026] Embodiment 2: The difference between this embodiment and embodiment 1 is that in the third step of this embodiment, the UV glue can be evenly applied to the leather substrate by coating, and then cured by UV drying.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Therefore, any modification, equivalent replacement, improvement, etc. made to the above embodiment based on the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. Leather color processing technology, characterized in that: The following steps are involved: The first step is substrate transfer. Prepare the leather substrate and transfer mold, apply UV glue on the transfer mold, place the leather substrate on the transfer mold, and squeeze it with a roller to make the UV glue fit the leather substrate. The second step is coating and coloring. The transferred leather substrate is placed in the coating equipment for optical coating to form multiple layers of colored solid films on the surface of the leather substrate.

2. The leather color processing process according to claim 1, characterized in that: Before the substrate transfer in the first step, surface treatment is also included, and the surfaces of the leather substrate and the transfer mold are dusted, degreased, and dried.

3. The leather color processing process according to claim 1, characterized in that: The substrate transfer in the first step also includes a curing process, which is carried out in a UV drying tunnel and cured by an ultraviolet lamp. The energy of the ultraviolet lamp is set to 1800 joules, the wavelength is 365-420nm, and the irradiation time is 3-5 seconds.

4. The leather color processing process according to claim 1, characterized in that: The first step of substrate transfer also includes preheating, during which the temperature is raised to 30-40°C.

5. The leather color processing process according to claim 1, characterized in that: When the first step is to use UV transfer equipment for transfer work, the hardness of the UV glue is 45-55 Shore D.

6. The leather color processing process according to claim 1, characterized in that: The coating equipment in the second step of coating and coloring is a thermal evaporation coating machine.

7. The leather color processing process according to claim 1, characterized in that: The second step is followed by a third step of inspection, which involves quality inspection of the leather substrate after coating and coloring.

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