KR100348096B1 - Method for forming polyurethane layer on a leather - Google Patents

Abstract

The present invention relates to a method of forming a polyurethane film on the surface of the leather fabric so as to smooth the texture of the leather surface and protect the surface, and to apply a release agent on a polyester film and to dry at 75 ℃ to form a release agent layer step; Applying a mixture of a polyurethane resin and a solvent using a roller on the release agent layer, and then drying at 100 ° C. for 20 to 30 seconds to form a polyurethane film layer; Applying a polyurethane two-component adhesive on the polyurethane film layer and drying at 20 to 30 ° C. for 2 minutes to form an adhesive layer; Coating a leather fabric on the adhesive layer; And detaching the polyester film, and thus, when the film is formed and printed and adhered to the leather fabric with a polyurethane resin as a main component, the leather does not penetrate the drug, thereby maintaining the leather form and being soft and cotton. This smoothness is not only possible to print a variety of patterns, but also to increase the productivity can reduce the production cost of the fabric.

Description

Method for forming polyurethane layer on leather fabric {Method for forming polyurethane layer on a leather}

The present invention relates to a method of forming a polyurethane film on the surface of the leather fabric, and more particularly, to a method of forming a polyurethane film on the surface of the leather fabric to smooth the texture of the leather surface and protect the surface.

In general, leather is widely used in a wide range, such as clothing, shoes or bags.

One of the problems with the practical application of leather to products is their weakness in water. If expensive leather products were exposed to rain, water stains would remain as stains even after being dried, and users had to use bitumen to seal the stains.

In addition, it is easy to be contaminated by other materials and when the surface of the leather texture is in contact with other objects, the damage caused by the pulling of the surface texture occurs, there was also a disadvantage that can not maintain the original texture.

Thus, while maintaining the texture of natural leather, efforts to improve the maintenance of color and waterproofness, breathability, feel and the elasticity of the material, and improve the durability of the leather.

Currently, leather fabrics and leather products are processed by direct chemical treatment on leather, roll coating, padding, printing or other printing methods. At this time, the drug has been mainly used a lot of water-soluble binder, or enamel coating method.

However, when the chemicals are directly processed on the leather in this way, the leather penetrates the chemicals and deforms the shape of the leather, or the leather becomes hard as time passes, and when pulled, cracks appear and the waterproof is not waterproof. There was a problem that the weight of the leather is heavier. In addition, there was a problem that mold or spew occurs during storage. For this reason, even if a product is exported, it is frequently returned.

On the other hand, the infiltration adhesive foam layer is formed on the upper surface layer of the natural leather, and the adhesive foam layer and the microporous surface layer are formed thereon, and the surface of the adhesive foam layer is scratched and polished by brush type buffing method. An example of manufacturing a natural leather treated with a surface of a metal is disclosed in Korean Patent Publication No. 1995-9564.

In the patent, a first step of adding a silica-based blowing agent to the thermoplastic polyurethane to dilute the toluene solvent and the pigment, and then foaming it on a release paper showing the surface and texture of the leather and completely drying it; Silica-based stabilizer is added to the low moldability and high-solid thermosetting two-component polyurethane with excellent flexibility and foamability on the dried foam coating surface of the first process to stabilize silica foam and structure, and the solid content is 75%. After adding a crosslinking agent and an anionic promoter, which is about a degree, the toluene solvent is diluted, applied, coated to a thickness of 0.03 mm, foamed and laminated with natural leather, and a release paper desorption chamber having an internal temperature of 70 to 80 ° C. for 48 hours. Polyurethane is coated and impregnated by removing the release paper by applying heat and then polishing the surface of the adhesive foam layer with brush type buffing to form a refined and smooth microporous surface layer like the surface texture of natural leather. Natural leather was produced.

However, such natural leather is formed to form a polyurethane layer by foam molding to be suitable for shoes or bags, and its appearance or texture is not suitable to apply to clothing, and it takes a long time to produce and a lot of space in the workplace. In addition, its high price and high price weakened its competitiveness for exports, making it unacceptable to audiences.

Therefore, the inventors formed a polyurethane film on a polyester film and indirectly bonded the surface of natural leather with a two-component polyurethane adhesive to smooth the surface of the leather fabric and maintain the softness as well as excellent waterproofing and preservation effect, deformation and It has been found that there is no alteration to complete the present invention.

Accordingly, an object of the present invention is to provide a method of forming a polyurethane film on a leather fabric which smoothes the leather surface and keeps the softness continuously, which is excellent in waterproofing and retaining effects and does not deteriorate and solves color contamination problems during operation. There is.

Method for forming a polyurethane film on the leather fabric of the present invention for achieving the above object comprises the steps of applying a release agent on a polyester film and drying at 75 ℃ to form a release agent layer; Applying a mixture of a polyurethane resin and methyl ethyl ketone using a roller on the release agent layer and then rapidly drying at 100 ° C. for 20 to 30 seconds to form a polyurethane film layer; Applying a polyurethane two-component adhesive on the polyurethane film layer and drying at 20 to 30 ° C. for 2 minutes to form an adhesive layer; Coating a leather fabric on the adhesive layer; And detaching the polyester film, wherein the leather fabric coated with the polyester film detachment is wound with a separate roller.

The present invention will be described in more detail as follows.

According to the present invention, a film is formed by using a polyurethane resin as a main component, and the adhesive is printed and then adhered to the leather work process so that the leather form is maintained, soft and smooth, and various patterns can also be printed and dried by properties. Productivity is improved compared to other methods and relates to a polyurethane film forming method that can be supplied at a low price.

Looking at the leather coating printing adhesive method in the present invention in detail.

In the present invention, in order to solve the problems caused by the leather surface treated with polyurethane in the conventional chemical treatment formula is applied on a separate film and laminated to it by an indirect coating method to form a polyurethane film.

To this end, a polyurethane film is first applied to a polyester film, and then a release agent is first applied onto the polyester film in order to form a polyurethane film on a leather fabric and then detach the polyester film in the course of winding with a roller.

Here, the preferred release agents are those selected from the group consisting of RC 200 consisting of 50 g of natural wax and 45 g of plasticizer and thermosetting resin.

The content of the release agent is preferably 12 μm thick with respect to the polyester film.

The release agent is applied onto a polyester film and then dried at 75 ° C. for 15 to 20 seconds by a dry drying method to form a release agent layer.

Then, to form a polyurethane film on the release agent layer, the polyurethane resin and the solvent are blended and applied to the release agent layer using a roller to form a film. Preferred solubilizers here are methylethylketone.

It is preferable that the polyurethane film is formed to have a thickness of 12 to 20 µm in view of workability and dry shortening.

A mixture of a polyurethane resin and a solvent is applied onto a release agent layer using a roller and then dried at 100 ° C. for 25 to 30 seconds by a dry drying method to form a polyurethane film layer.

Next, in order to bond the polyurethane film and the leather fabric, a two-component polyurethane adhesive is applied on the polyurethane film layer to form an adhesive layer. At this time, it is dried for 2 minutes at 20 ~ 35 ℃ to evaporate all chemicals, moisture and then duct to maintain 20 to 35 ℃.

Then, when the leather and the adhesive layer formed with the polyurethane film is passed through the hydraulic press roller, the polyurethane film is coated and adhered to the leather fabric to complete the product. At this time, the polyester film layer is detached and wound up through a separate roller while winding up the leather fabric coated with the polyurethane film.

In more detail, when the polyester film formed with a polyurethane film passes through a hydraulic heat roller together with leather, the upper portion of the polyester film passes through the polyester film and the lower portion of the polyester film passes through the leather. At this time, the adhesive is completely hardened by heat and adhered to the leather so that a polyurethane film is formed on the leather and falls to the lower portion to produce a finished product of the leather.

Hereinafter, the present invention will be described in detail with reference to the following Examples, but the present invention is not limited by the Examples.

Example 1

50 g of a release agent (RC-200, manufactured by Jumbo Tech Co., Ltd.) was mixed with 30 g of methyl ethyl ketone, 10 g of methyl cellosolve, and 10 g of toluene, and applied to a polyester film (SK Co., Ltd.), followed by a dry dryer (75 ° C). , 25 seconds), 80 g of polyurethane resin (SUP-240, 30 ± 1% solids, molecular weight 50,000, Samsung Chemicals) and 20 g of methyl ethyl ketone were mixed to form a film by roller printing on the release layer surface. It was formed and passed through a dry drying method for 30 seconds at 100 ℃. In this case, colors may be injected as necessary to represent various colors.

Then, 100 g of a two-component polyurethane adhesive (PD-2000, 60 ± 1% solids, 80,000 mass, Dream Trading Co.) 100g, a curing agent (PD-1366, 70 ± 1% solids, molecular weight 1,500) to the polyurethane film layer Was mixed with 100 g of methyl ethyl ketone and roller-printed, then passed through a dry dryer for 2 minutes, and then coated on a natural leather fabric.

Then, the polyester film was removed by passing through a hydraulic heat roller, and at the same time, the leather fabric on which the polyurethane film was formed was wound up.

Cracks, abrasion, adhesive strength and elasticity were measured for the leather fabric thus manufactured. Specifically, the elasticity was twice as large as the actual size as measured by the strap (10cm × 10cm).

No cracking phenomenon was observed, and the adhesive strength of the same part was tested more than 10 times with the strong adhesive tape, and the polyurethane film was intact. The abrasion test was proved as a good result by rubbing the rubber eraser 10 times or more.

As described in detail above, in the case of printing and bonding by forming a film with a polyurethane resin as a main component on the leather fabric as in the present invention, since the chemicals do not penetrate the leather during adhesion, the leather form can be maintained semi-permanently and softly. As it is smooth and smooth, it is possible to print various patterns as well as shorten the working time to reduce production cost and contribute to the competitiveness of the international market by arranging new penis in the leather market, a domestic and overseas specification industry.

Claims (3)

Applying a release agent on a polyester film and drying at 75 ° C. to form a release agent layer; Applying a mixture of a polyurethane resin and methyl ethyl ketone using a roller on the release agent layer and then rapidly drying at 100 ° C. for 20 to 30 seconds to form a polyurethane film layer; Applying a polyurethane two-component adhesive on the polyurethane film layer and drying at 20 to 30 ° C. for 2 minutes to form an adhesive layer; Coating a leather fabric on the adhesive layer; And Desorbing the polyester film, A method of forming a polyurethane film on a leather fabric, characterized in that the leather fabric coated with the polyester film detachment is performed to be wound by a separate roller. delete delete