JPH0931859A - Wet type preparation of synthetic leather and its intermediate product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain artificial leather which has excellent visual appearance, touch feeling, air-permeability and mechanical properties, and is of close resemblance to genuine leather by using a wet-type method for production. SOLUTION: This method for producing artificial leather comprises pretreating a base material 5 to have peel strength of 10-30g/cm, forming a wet-type silver layer 7 on the base material 5, peeling the base material 5 after post-treatment, thus producing a wet-type silver layer product, and bonding an base cloth 18 to the surface of the wet-type silver-layer product 17 from which the base material 5 has been peeled by coating the surface with an adhesive or otherwise the base cloth 18 with an adhesive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing wet synthetic leather, in particular, a wet silver produced by appropriately pretreating a substrate, coating a polyurethane wet resin solution, and then peeling the substrate. The present invention relates to a method for producing wet synthetic leather improved by adhering a base fabric to a layer product and an intermediate product thereof.

The term "wet silver layer" as used herein means a known surfactant, filler, DMF (Dimethyl f) for a polyurethane wet resin solution using a solvent which is easily dissolved in water.
It refers to a fine porous structure layer obtained by coating a compounding solution containing ormamide).

[0003]

2. Description of the Related Art Synthetic leather is a concept to be compared with natural leather, and its manufacturing method is well known as a dry method or a wet method.

The dry method is a method of producing synthetic leather by coating a base fabric with a polyurethane resin solution, which is mainly a coating film of synthetic leather, and then heat-drying to evaporate the solvent in the polyurethane resin solution. As shown in FIG. 7, the release layer 1 on which the required irregularities (patterns) are engraved is coated with a polyurethane one-pack type resin to complete the coating layer 2 and then the polyurethane layer 2 which is the adhesive 3 is applied. After the liquid type resin is applied, the woven fabric 4 is bonded thereto by a roller pressure bonding means, and the release paper 1 is peeled off to complete the process.

On the contrary, in the wet method, after coating the polyurethane resin solution on the base fabric, it is put in water,
Then, the solvent in the polyurethane resin solution is extracted in water to produce synthetic leather. As shown in FIG. 8, the polyurethane wet resin solution is directly coated on the woven fabric 4, put in water, and when the solvent is extracted, it is taken out and washed with water, dried and the like. Can be completed by solidifying to obtain the wet silver layer 7 having a large number of fine pores 13.

Generally, such a wet method can be coated thicker than a dry method, but the solvent-removed fine pores 13 are formed innumerably in the wet silver layer 7 and have good air permeability. It has the advantage of becoming a soft sponge and giving it a very soft touch.

However, the feel of the artificial leather by the above-mentioned dry method gives a soft and firm feeling, and since the release paper has to be used, the delicate real pattern (that is, the real pattern by the release paper) is reproduced. However, when manufacturing synthetic leather by the wet method, it is necessary to impregnate the base fabric in water during the manufacturing process. In some cases it may not be possible to do so, or as split fabric split leather
When r) is used, the split leather is directly coated with the polyurethane wet resin solution and then taken into water, so that the split leather is bubbled.
It may stand up, and if you apply water-repellent treatment to prevent foaming and then coat it, not only is it difficult to form the wet silver layer itself, such as the decrease in adhesive strength, but the split leather is soaked in water and then dried. If you do it
This is because the outer shape is deformed and becomes awkward. That is, there is a drawback in that the value of the product is rather lowered by the wet processing.

Further, in the conventional dry method and wet method, since a wet silver layer is formed on the upper surface of a specific base fabric after selecting a specific base fabric, there is a drawback that a product cannot be produced unless the base fabric is defined. there were.

[0009]

In contrast to such a conventional technique, the inventor of the present invention pretreats the substrate 5 as shown in FIG. 3 and FIG. A substrate which is processed to have strength and has a first step of forming a wet silver layer 7 on the upper surface thereof by a normal wet method, and a wet silver layer product 7a produced in the first step, which is sequentially transferred. Adhesive is coated on the opposite silver layer surface where 5 is not adhered by a coater 19 and semi-dried in a hot air drying chamber 20, and a split leather provided from a discharge roller 21 is pressed onto the wet silver layer product 7a. , Aging room 2
Inventing the method of post-processing after the base material 5 is peeled from the wet silver layer 7 after being cross-linked in 3 (disclosed in Korean Patent Publication No. 90-7191), the above problems have been partially solved.

However, even in the above-mentioned wet synthetic leather manufacturing method, the split leather is adhered to the smooth wet silver layer surface on which the base material is not contacted, and the surface from which the base material is peeled off is post-treated. This caused the following inconveniences.

(1) Since the split leather 18 is adhered to the smooth surface of the wet silver layer 7 on which the substrate 5 is not adhered, the adhesion between the two is not good, and (2) the wet silver coated with an adhesive. Post-processing is not easy by post-processing the layer surface, and the quality of the product is inferior because the pattern and hue are not beautiful or delicate even if post-processing is performed. Since the volume of the intermediate product is increased due to peeling, not only is it difficult to transfer the intermediate product, but also the work efficiency is reduced and the manufacturing cost is increased.
(4) Since the synthetic leather is continuously manufactured, there is a disadvantage that only the wet silver layer as an intermediate product is separated and difficult to sell or store.

[0012]

Means for solving the above-mentioned problems are as follows.

(1) 10 g / cm to 3 by pretreating a substrate
It has a peel strength of 00 g / cm, a wet silver layer is formed on the upper surface thereof by a usual method, and after the post-processing treatment, the substrate is peeled to produce a wet silver layer product, and then the wet silver is produced. A method for producing wet synthetic leather, characterized in that the base material of the layered product is coated with an adhesive or the base fabric is coated with an adhesive to bond the above-mentioned base fabric.

(2) In the above item (1), the base fabric is selected from the group consisting of split leather, non-woven fabric, woven fabric, knitted fabric, polyester film, nylon film, wet synthetic leather and dry synthetic leather. A method for producing wet synthetic leather, characterized in that it comprises different kinds of substances.

(3) In the above item (1), the base material is a polyethylene terephthalate film, polyester oxpod, nylon film, nylon taffeta, polyester fabric, nylon oxpod, T / C and cotton fabric. 1. A method for producing wet synthetic leather, which is one kind of substance selected from the above.

(4) A method for producing wet synthetic leather according to the above item (1), wherein the pretreatment step can be carried out by water treatment, release agent treatment, or binder treatment.

(5) The method for producing wet synthetic leather according to the above item (1), wherein the coating step is performed by a gravure coater, a knife coater or a reverse roll coater.

(6) The substrate is pretreated to be 10 g / cm to
An intermediate product comprising a wet silver layer product obtained by imparting a peel strength of 300 g / cm, forming a wet silver layer on the wet silver layer by a usual method, post-treating and then peeling the base material. .

As a result, wet synthetic leather most similar to natural leather which could not be produced by the conventional method can be produced.

[0020]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the accompanying drawings.

The method for producing wet synthetic leather according to the present invention comprises the first step of forming a wet silver layer and the second step of peeling the wet silver layer from the substrate to obtain a wet silver layer product, the wet silver layer product. And a third step of making synthetic leather using the base fabric.

In the first step of producing the wet silver layer, the substrate 5 is pretreated in a water tank 8, a coater 8a and a drying chamber 9 as shown in FIG. 4 to give a peel strength of 10 to 300 g / cm. It is a step of forming a wet silver layer thereon by a usual method.

The substrate 5 used in the first step of the present invention must be strong enough to withstand the tensile force of the machine during the whole process of the present invention, and is peeled from the silver layer during the operation. The carrier which has been removed after the post-processing work while continuing to support the silver layer.
r), so nylon film, 21
0T Nylon Taffeta,
190T nylon taffeta, 152T / C, 168T /
C, polyethylene terephthalate film, polyethylene terephthalate 3-5 denier filament 80-
It is preferable to use a polyester oxpod (hereinafter referred to as polyester oxpod), a polyester (polyester) woven fabric, a nylon oxpod, a cotton woven fabric or the like woven as a plain weave by twisting with 450 denier.

In the present invention, it is carried out before the wet silver layer 7 is formed. The above-mentioned pretreatment steps include water treatment, mold release agent treatment and adhesive treatment (binder treatment), which are selectively combined. You can also do it.

In the above water treatment, if nylon taffeta or oxpod is used as the base material 5 as it is, the wet coating liquid penetrates to the back surface of the base material, and the base material cannot be separated from the wet silver layer to be used. Because there is
Just before the coating liquid penetrates to the back side,
This is a method of immersing the back surface in water in the water tank 8 to solidify it, or rather, slightly moistening the base material from the beginning.

The above-mentioned release agent treatment is a method in which a silicone water repellent or a fluorine water repellent is dissolved in water and used.
A method in which a 0.1 to 20% aqueous solution is prepared in order to perform a water repellent treatment within a range in which the adhesive force with the base material is not unduly reduced, the base material is impregnated with the solution, and then dried and cured in a drying chamber 9. Is.

The above adhesive treatment is carried out by adding a crosslinking agent and a solvent to a polyurethane one-pack type resin or a polyurethane two-pack type resin, and a knife coater (Knife coater) is applied at a coating amount of about 5 to 300 g / m ^2. , A gravure coater or a reverse roll coater 8a. In the case of a fabric such as nylon taffeta, Oxpod, T / C, etc., the fabric may be calendered before the coating in order to prevent the coating solution from permeating evenly.

As described above, in the present invention, the reason why the pretreatment step which is not used in the usual wet silver layer manufacturing method is performed is that the wet silver layer product itself is not a finished product (independently used product). This is because it can be sold as an intermediate product by adhering it to a base fabric, etc. Another reason is that after the process of forming the silver layer or considering the texture of the surface and the visual point, post-processing such as buffing with sandpaper. This is because it must not be peeled off in the process, and has a peeling strength suitable for peeling off from the substrate as well as possible after post-processing.

Illustrative Drawing FIG. 5 is an enlarged cross-sectional view of the first stage process product in which the wet silver layer 7 and the substrate 5 are formed.

Illustrative Drawing FIG. 6 is an enlarged cross-sectional view of a product obtained by post-processing the wet silver layer 7.

FIG. 6 is an enlarged cross-sectional view of the state where the wet silver layer is post-processed. The dry process described above is performed again (FIG. 6 (a)), or a pattern and a hue are added by surface treatment so that the physical properties of the surface are improved. , Whether the appearance and feel are good (Fig. 6 (b)), or the pattern is engraved by a heated embossing roller (Fig. 6).
(C)), or polishing with sandpaper (Buffing)
It is also possible to make suede (FIG. 6D), and two or more kinds of the above methods can be used.

Illustrative Drawing FIG. 7 is an enlarged cross-sectional view of the second step of peeling the substrate 5 from the wet silver layer product 17 formed in the first step.

According to the present invention, the third step of producing the synthetic leather is the wet silver layer product 1 produced in the above second step.
7 is a step of adhering the base cloth 18 to the base cloth 18 to produce wet synthetic leather as shown in FIG.

In the third step of the present invention, as shown in FIG. 8, an adhesive coater is used to apply an adhesive to the wet silver layer surface from which the base material 5 has been peeled off while sequentially transferring the wet silver layer product 17 described above. By coating with 19 and semi-drying in the hot air drying chamber 20, the wet silver layer product 17 and the base fabric 18 provided from the discharge roller 21 are pressed by the press roller 22 and crosslinked in the aging chamber 23. A wet synthetic leather product of the present invention was obtained. On the other hand, the adhesive is the base fabric 1
8 can also be coated.

In this case, the above-mentioned base fabric 18 can be made of split leather, non-woven fabric, woven fabric, knitted fabric, polyester film, nylon film, etc., and wet synthetic leather or dry synthetic leather can be used as the base fabric. It is also possible to form the layers in duplicate. Moreover, the above-mentioned adhesives include polyurethane two-component resin, polyurethane cross-linking agent, cross-linking accelerator, and MEK (Methyl Ethyl Keto).
ne) solution, which is coated at a coating amount of about 80 to 250 g / m ² using a coater 8 a, and left in the aging chamber 23 at about 60 ° C. for about 24 hours to make the polyurethane adhesive 18 Is cross-linked.

The present invention, which is constituted as such a process, prevents any problems in working that occur when the base material is directly wet-coated, for example, formation of foam, deterioration of adhesive strength and deterioration of quality. Not only that, by cross-linking a wet silver layer with excellent physical properties and various base fabrics, the appearance, feel, breathability, and breathability of conventional wet synthetic leather or dry synthetic leather whose base material is split leather are improved. We came to manufacture wet synthetic leather products with excellent mechanical properties and the like.

Further, when the wet synthetic leather manufacturing method of the present invention is used, the base material of the wet silver layer product 17 is not adhered and is smooth as compared with the conventional technique in which the base material is peeled in the final step. Since the surface can be post-processed, the post-process is facilitated, and various surface treatments can be applied to obtain not only beautiful and delicate patterns and hues, but also the substrate 5
Since the intermediate product is peeled off in the middle of the process, the intermediate product can be easily transferred and processed, the working efficiency is improved, and the wet silver layer itself which is the intermediate product can be sold. Further, the base material 5 has the advantage that the adhesion between the two is improved by adhering the base fabric 18 to the adhering surface of the peeled wet silver layer product 17.

Examples of the present invention will be described below. The first stage (Example 1-5), the second stage (Example 6) and the third stage (Examples 7-8) will be specifically described below. Is like.

Example 1 A point of 10,000 cp was applied to the upper surface of 210T nylon taffeta.
Polyurethane wet resin of s (20 ° C) (solid content 100 parts 30%) Anionic surfactant 1 part Nonionic surfactant 1 part DMF 50 parts Direct coating with a knife coater for 1.0 mm 20 seconds later Fabric Moisten the back side evenly with water. 40 ° C
It was solidified in water for 10 minutes, washed with water at 60 ° C. for 30 minutes (completely extracting DMF) and then dried at 120 ° C. for 10 minutes to obtain a wet silver layer having an appropriate peel strength.

At this time, as the coater, a gravure coater or a reverse roll coater can be used outside the knife coater.

Example 2 After impregnating 210T nylon taffeta with water and passing it through a drying roller to semi-dry the water content to about 70%, the solution of Example 1 was coated and coagulated as in Example 1. It was washed with water and dried to obtain a wet silver layer having an appropriate peel strength.

(Example 3) One 210T nylon taffeta
% Silicon-based water repellent solution and then dried at 120 ° C. for 1 minute and aged at 180 ° C. for 3 minutes, and then the solution of Example 1 is coated, coagulated, washed with water as in Example 1.
It was dried to obtain a wet silver layer having an appropriate peel strength.

(Example 4) Polyester oxpod (polyethylene terephthalate 3-5 denier filament is continuously woven with 80-450 denier and woven into a plain weave) is impregnated with a 1% fluorine-based water repellent aqueous solution. After 150 ℃
After passing through a drying roller of about 80% and semi-drying, the solution of Example 1 was coated, coagulated, washed with water and dried in the same manner as in Example 1 to obtain a wet silver layer having an appropriate peel strength.

(Example 5) Polyethylene terephthalate film having a thickness of 0.05 to 0.20 mm Polyurethane one-pack resin 100 parts (solid content 30%) Toluene 30 parts MEK (Methyl Ethyl Ketone) 30 parts The solution of Example 1 was coated with a knife coater, a gravure coater or a reverse roll coater at 20 to 50 g / m ^{2 and} dried for 1 minute, and then the solution of Example 1 was coated, coagulated, washed with water and dried as in Example 1 to obtain a suitable solution. A wet silver layer having various peel strength was obtained. On the other hand, the substrate is a nylon film instead of a polyethylene terephthalate film,
The same effect was obtained by replacing with polyester fabric, nylon oxpod, T / C or cotton fabric.

(Embodiment 6) The wet silver layer having the base material adhered thereon produced in the above-mentioned Embodiments 1 to 5 was subjected to surface treatment by a gravure coating roll as a post-processing and was heated with an embossing roller. After the pattern was imprinted or the surface was sanded with sandpaper, the substrate was peeled off to obtain a wet silver layer product.

Example 7 Polyurethane two-component resin 100 parts (solid content 60%) Polyurethane cross-linking agent (solid content 75%) to the backside after processing of the wet silver layer prepared in Example 6 10 parts Cross-linking accelerator 1 part MEK (Methyl Ethyl Ketone) 20 parts solution was coated with a gravure coater at 80 to 250 g / m ² and further dried for 1 minute and half in a hot air drying room at 60 ° C. then split leather was applied to the upper surface. It was pressed by a press roller. The wet synthetic leather of the present invention was obtained by leaving it in a aging room at 60 ° C. for 24 hours and then pulling it out.

Example 8 A wet synthetic leather of the present invention was obtained in the same manner as in Example 7, except that a nonwoven fabric was used instead of split leather.

[0048]

As described above, according to the present invention, the substrate is appropriately pretreated without directly applying the wet coating to the base fabric, the wet silver layer is formed, and then the desired post-treatment is performed. After the treatment, the base material is peeled off, and the base fabric is bonded to the surface of the wet silver layer product from which the base material is peeled off, whereby a wet synthetic leather that is very similar to natural leather that has not been obtained in the past can be provided.

Further, since the base material is peeled off in the middle of the process, it is easy to transfer and process the intermediate product, the work efficiency is increased, and the wet silver layer itself which is the intermediate product can be sold. There is.

[Brief description of drawings]

FIG. 1 is an exemplary view of a process of forming a wet silver layer on a substrate surface according to the present invention.

FIG. 2 is an enlarged sectional view of a wet silver layer product according to the first step of the present invention.

3 (a), (b), (c) and (d) are enlarged sectional views of a wet silver layer product obtained by post-processing the wet silver layer according to the present invention.

FIG. 4 is an enlarged cross-sectional view of a process of peeling a wet silver layer product and a substrate according to the present invention.

FIG. 5 is an exemplary diagram of a process of bonding a wet silver layer product and a base fabric according to the present invention.

FIG. 6 is an enlarged sectional view of wet synthetic leather according to the present invention.

FIG. 7 is an enlarged cross-sectional view of conventional synthetic leather using a woven fabric as a base fabric by a dry method.

FIG. 8 is an enlarged cross-sectional view of conventional synthetic leather using a woven fabric as a base fabric by a wet method.

FIG. 9 is a process diagram showing a conventional method for producing wet synthetic leather.

[Explanation of symbols]

 1 Release Paper 2 Dry Coating Layer 3 Adhesive Layer 4 Fabric 5 Base Material (or Support) 6 Pretreatment Layer 7 Wet Silver Layer 7a Wet Silver Layer Product Combined with Base Material 8 Water Tank 8a Coater 9 Dry Chamber 10 Wet resin coating 11 Coagulation 12 Washing with water 13 Micropores 14 Surface treatment surface 15 Embossing surface 16 Suede leather surface 17 Wet silver layer product 18 Base fabric 19 Adhesive coater 20 Hot air drying chamber 21 Release roller 22 Press roller 23 Aging Muro 24 Wet synthetic leather

Claims (6)

[Claims] 1. A substrate is pretreated to have a content of 10 g / cm to 300 g.
It has a peel strength of g / cm, a wet silver layer is formed on the upper surface by a usual method, and after the post-treatment, the base material is peeled to produce a wet silver layer product, and then the wet silver layer is prepared. A method for producing wet synthetic leather, characterized in that the base material of the layered product is coated with an adhesive or the base fabric is coated with an adhesive to bond the above-mentioned base fabric. 2. The method according to claim 1, wherein the base fabric is selected from the group consisting of split leather, non-woven fabric, woven fabric, knitted fabric, polyester film, nylon film, wet synthetic leather and dry synthetic leather. A method for producing wet synthetic leather, characterized by comprising a substance. 3. The substrate according to claim 1, wherein the substrate is a polyethylene terephthalate film, a polyester oxpod, a nylon film, a nylon taffeta, a polyester woven fabric, a nylon oxpod, a T / C and a cotton woven fabric. A method for producing wet synthetic leather, which is one selected substance. 4. The method for producing wet synthetic leather according to claim 1, wherein the pretreatment step can be performed by moisture treatment, release agent treatment, or binder treatment. 5. The method for producing wet synthetic leather according to claim 1, wherein the coating step is performed by a gravure coater, a knife coater, or a reverse roll coater. 6. A substrate is pretreated to have a concentration of 10 g / cm to 30.
An intermediate product consisting of a wet silver layer product obtained by peeling the substrate after having a peel strength of 0 g / cm, forming a wet silver layer on the wet silver layer by a usual method, post-treating the same. .