JPH0430892B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to interior materials such as vehicles, walls, etc., shoes, bags, and other items that have an excellent suede feel and design with fine fluff on the surface. The present invention relates to a method for producing a suede-like plastic sheet useful as a material for miscellaneous goods.

[Conventional technology]

Conventionally, as a method for manufacturing suede-like plastic sheets, methods of electrostatic flocking on plastic sheets have been widely used in a wide variety of ways. Another known method is to press a thermoplastic resin sheet in a heated molten state onto a roll having pores, press it into the pores of the roll, and then peel it off while stretching the surface layer through the pores. There is.

However, the former method has drawbacks such as coloring of the flocked short fibers and adhesion of the short fibers to the plastic sheet, and also has insufficient light fastness, heat resistance, and discoloration properties due to dyes. Furthermore, as a means to solve this problem, it is possible to color the short fibers with pigments that have excellent light and heat resistance, but it is impossible to dye with pigments, and short fibers manufactured by kneading pigments in advance cannot be used. Due to the complicated manufacturing process, it is difficult to freely obtain and use a variety of desired colors. On the other hand, emulsion-type adhesives have come to be commonly used to bond short fibers from the viewpoint of environmental hygiene during work and fire prevention, but products using such adhesives It has poor moisture and heat resistance and water resistance, and depending on the usage conditions, the short fibers that are joined may fall off, which not only spoils the appearance of the product, but also
The manufacturing process also has various drawbacks such as complication.
On the other hand, as a method for manufacturing suede-like plastic sheets using the latter roll,
No. 2234, etc., but with this method, it is not only extremely difficult to produce rolls with micropores, but also because the sheet is stretched in a heated molten state and peeled off from the roll during production, so the shape of the individual fluffs is difficult to produce. The fluff becomes irregular, and the fineness and density of the fluff becomes insufficient, making it difficult to obtain a suede-like feel.Furthermore, the valleys between the fluffs become glossy, which may cause problems in appearance depending on the application. It has various drawbacks such as:

[Problems to be solved by the present invention]

As mentioned above, the present invention has no drawbacks in the fluff colorability, light resistance, heat discoloration resistance, heat and humidity resistance, water resistance, bondability, etc. caused by the short fibers used, and also has environmental sanitation during production. To manufacture a suede-like plastic sheet that can be easily and continuously manufactured without causing problems such as surface area, fire, etc., has an excellent color tone design, and has an excellent suede feel with dense and fine fluff. The present invention provides a method.

[Means for solving problems]

The present invention consists of a first step and a second step.
As a process, a material with a surface consisting of a large number of dense napped short fibers is used as a prototype, and an uncured curable silicone rubber that is fluid at room temperature is applied to this surface so that the napped fibers of the material are buried. Then, after curing the silicone rubber, the material is removed to produce a cured silicone rubber mold, and then a second
As a process, a plastic material that is fluid at room temperature is coated on the cured silicone rubber mold, and after solidification, the plastic material is peeled off to produce a suede-like plastic sheet.

[Effect]

Hereinafter, the first step and the second step will be sequentially explained.

First step The cured silicone rubber mold of the present invention is made of a material having a large number of dense napped short fibers on the surface of a knitted fabric such as a short fiber electrostatic flocked body, a pile-cut interwoven fabric, or a short fiber raised fabric. Select and use as appropriate. In this case, if the above-mentioned prototype material is an electrostatic flocking body and a raised fabric, and the other parts are knitted fabrics or piled fabrics, the paint will be applied to the front and back of the material during the uncured silicone rubber application process in the next operation. If the so-called bleed-through phenomenon occurs due to the passage of the material, a film, sheet, or plate-like material may be attached to the back surface of the material, or a filler paint may be applied to the back surface of the material.

The fiber length of the many dense napped short fibers of the original material,
The thickness and thickness are in the range of 0.1 to 20 denier and 0.2 to 5 mm, respectively, considering the suede feel of the suede-like plastic sheet to be finally obtained and the ease of peeling of the plastic material from the mold in the second step described below. It is better to select and use the appropriate one.

Next, uncured silicone rubber, which is cured by heating at room temperature or low temperature, is applied onto the master material. In this case, it is best to apply the coating at a thickness that is at least greater than the short fiber length of the original shape, so that the short fibers are buried.This prevents the formation of undesirable through holes in the coated silicone rubber layer. I can do it.

When applying the uncured silicone rubber to the master material, it is necessary to avoid the inclusion of air bubbles. Normally, air bubbles that enter during application disappear by the time it cures after application, but air bubbles are already mixed in the uncured silicone rubber itself. If the rubber is difficult to defoam due to its high viscosity or the structure of the original mold, the rubber may be defoamed under vacuum.

Next, the applied uncured silicone rubber is left at room temperature or heated at low temperature (50 to 150°C) to harden and solidify, and then the prototype material is removed to obtain a silicone rubber mold. It is important not to damage the mold, as any damage to the mold will result in a loss of the suede feel of the final sheet product. If the short nap fiber length of the material is short, a silicone rubber mold can be created by simply peeling it off, but if the fiber length is long and the silicone rubber mold is easily damaged during peeling, the original material should be decomposed or dissolved with a solvent. It is preferable to remove it by For this decomposition or dissolution, it is sufficient to select and use known solvents as appropriate depending on the material of the prototype material, and if the prototype material is made of multiple materials, apply solvents for each material in turn. Just apply it. When using the agent, it is preferable to select in advance one that is easy to decompose or dissolve the material. In any of the above cases, materials that cause extreme deterioration of silicone rubber should be avoided. A cured silicone rubber mold can thus be produced. Cured silicone rubber molds are not only made of silicone rubber, but also woven fabrics, knitted fabrics, negative woven fabrics, films, sheets, plate-like materials, etc. are laminated as reinforcing materials, and they can also be used in belt-like, roll-like, and other shapes. It can also be used repeatedly.

The electrostatic flocking material used in the above-mentioned prototype of the present invention can be made of woven fabrics, knitted fabrics, non-woven fabrics, various synthetic resin films, sheets, and plates, in which short fibers having various fiber lengths and thicknesses are statically applied. The raised fabric used is a raised fabric made by raising woven fabrics, knitted fabrics, and non-woven fabrics made of various fibers to the same length and thickness as described above. Examples of pile-cut piled fabrics include velvets such as cotton velvet and double velvet having the same fiber length and thickness as described above, horizontal pile brush, and kohl fabric.

The silicone rubber used above is a room temperature curing type (RTV) or low temperature heat curing type (LTV) silicone rubber that is liquid when applied to the mold material but hardens after coating, and is suitable for mold making. for,
Commercially available 2-3 liquid (hardening type) for potting electrical and electronic equipment can be used, but
In either case, it is necessary to have mold releasability, heat resistance, and chemical resistance after curing.

In addition, the solvents that decompose or dissolve and remove the original mold material mean those that decompose or dissolve the original mold material into a gaseous or liquid state, and there are many solvents for each material, but the following are commonly used. Things are exemplified.

(a) For cotton and rayon Sulfuric acid, copper ammonia solution.

(b) For polyamides Hydrochloric acid, sulfuric acid, nitric acid, formic acid, glacial acetic acid, calcium chloride methanol solution, phenol, m-cresol, butyrolactone, caprolactam, dimethyl sulfoxide, benzyl alcohol, aniline, etc.

(c) For polyacrylonitrile-based substances Sulfuric acid, nitric acid, dimethylformamide, butyrolactone, caprolactam, dimethyl sulfoxide, etc.

(d) For acetate Hydrochloric acid, sulfuric acid, nitric acid, formic acid, glacial acetic acid, acetone, cyclohexanone, phenol, m-cresol, dimethylformamide, butyrolactone, tetrahydrofuran, dioxane, methylene chloride, methylene chloride-alcohol, chloroform, nitromethane, nitrobenzene, Ethylenediamine hydrate, caprolactam, dimethyl sulfoxide, benzyl alcohol, aniline, pyridine, morpholine, etc.

Second Step: A plastic material that is fluid at room temperature is applied to the cured silicone rubber mold produced in the first step. As a coating method, a conventional method for coating plastic materials, such as a knife coater, a bar coater or a roll coater, is used. In this case, the plastic penetrates into the micropores of the cured silicone rubber mold, forming the part that will become the fluff after manufacture, and also forms on its outer surface a uniform sheet-like part that serves as a base for supporting the fluff part. .

As mentioned above, since the plastic material needs to fully penetrate into the micropores of the cured silicone rubber mold, it is preferable to have a low viscosity, for example, a viscosity of 50 to 50,000 cps at room temperature and fluidity. In addition, the plastic material must be able to fully penetrate into every corner of the micropores of the cured silicone rubber mold and faithfully reproduce the shape of the micropores. must be of good quality. Therefore, the plastic material of the present invention can be prepared by dissolving various types of plastic in an organic solvent or by using it as a low-viscosity paste coating.

The plastic material applied to the cured silicone rubber mold as described above is heated or dried to solidify. For such a method, conventional equipment used for drying plastic paints can be used;
far infrared heater, infrastein heater,
A hot air drying oven or the like is a recommended device in terms of uniform drying and ease of operation.

Once solidified, the plastic material is peeled off from the cured silicone rubber mold to obtain a sheet. In this case, in order to extract the fluff part of the sheet-like material from the fine holes of the cured silicone rubber mold without cutting it, the fluff part needs to have enough strength to withstand the extraction operation, and for this reason, it is recommended to cool it appropriately beforehand. good.

Although the sheet-like product of the present invention can be used as a single plastic material, other materials (paper, flame-retardant paper, woven fabric, knitted fabric, non-woven fabric, glass cloth, plastic sheet, or two or more of these) may be used as appropriate. It can also be used by using an adhesive or by bonding after heat treatment.

Further, by subjecting the surface of the sheet-like material to secondary processing such as embossed patterns, printed patterns, and in some cases, valley print patterns, it is possible to impart a more three-dimensional and versatile design. In this case, the embossed pattern may be formed either before or after the printed pattern is formed.

Further, by sequentially applying two or more plastic materials having different color tones onto a cured silicone rubber mold in the form of a pattern, it is possible to obtain a sheet-like product having various designs having arbitrary patterns.

As the resin used in the present invention, any plastic material with low viscosity may be used, but polyvinyl chloride, polyurethane, polyamide, etc. are suitable, and as the paste coating, polyvinyl chloride paste is used from the above point of view and It is optimal from the point of view of processability. Also, the material is uncolored,
It can be used in any case of coloring, but in the case of coloring, by using pigments, it is possible to obtain a product with less heat resistance and weather resistance deterioration and excellent durable discoloration. The thus obtained product of the present invention has an excellent suede feel and can be used as a highly decorative sheet material for interior materials such as automobiles, wall covering materials, furniture, shoes, bags, etc.
It is also useful as a material for other daily necessities.

Next, the present invention will be explained by examples, but the present invention is not limited thereby. Note that the numbers in the examples are parts by weight.

Example 1 First step The raw material was a dense rayon woven fabric flocked with nylon pile with a thickness of 3 denier and a fiber length of 1 mm, and uncured silicone rubber for molding (manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to this material. Mixture of two-component RTV rubber for mold making, KE-113, 100 parts, Cat-RM 0.5 parts)
was applied to a thickness of about 3 mm and left at room temperature for 24 hours to harden. Next, when this was immersed in 90% formic acid at room temperature, the rayon woven fabric separated and was removed and left immersed in the solution for an additional 24 hours to dissolve the nylon pile and remove the material. Thereafter, the silicone rubber was taken out, washed with water to remove adhering formic acid, and dried at 120°C for 1 hour to obtain a cured silicone rubber mold. When the cured silicone rubber mold was examined under a microscope, it was found that the short nylon fibers had been completely removed and it had many dense, fine pores.

2nd step: Apply a polyvinyl chloride paste paint having the composition below to a thickness of about 0.5 mm on the cured silicone rubber mold, heat it at 170°C for 7 minutes, gel it, cool it, and remove it from the silicone rubber mold. When the solidified polyvinyl chloride sheet was peeled off, a suede-like polyvinyl chloride sheet having many dense and fine fluffs on the surface and an excellent suede feel was obtained.

Composition of polyvinyl chloride paste Polyvinyl chloride resin (paste resin G135J manufactured by Nippon Zeon Co., Ltd.) 100 parts Plasticizer (DOP) 70〃 Epoxidized soybean oil 3〃 Stabilizer 2〃 Pigment (ivory color) 8〃 Above composition When the viscosity of the substance was measured, it was found that it was approximately
It was 5000cps (25℃).

Example 2 The cured silicone rubber mold described in Example 1 was used to prepare ivory paste paints having the same composition as in Example 1 and blue paste paints differing only in the pigment. First, the blue paste paint was applied to the cured silicone rubber mold in a pattern using a screen printing method, and then the ivory paste paint was applied over the entire surface using a bar coater. Thereafter, it was processed in the same manner as in Example 1 to obtain a suede-like polyvinyl chloride sheet having a pattern and an excellent suede feel.

Example 3 First step Cotton velvet was used as a prototype, and uncured silicone rubber for potting (2-component RTV rubber KE- for electrical and electronic transparent potting manufactured by Shin-Etsu Chemical Co., Ltd.) was used as a prototype.
106 and 10 parts of CatRG) was applied to a thickness of approximately 5 mm and subsequently cured by heating at 150° C. for 1 hour. After cooling, take out the cured silicone rubber.
Immersed in copper ammonia solution, washed with water, and then heated at 120℃ for 1
After drying for a while, a cured silicone rubber mold was obtained. When the cured silicone rubber mold was observed under a microscope, it was confirmed that the cotton velvet had been completely removed and that it had many dense, fine pores.

2nd step: Apply polyvinyl chloride paste paint with the composition below to a thickness of approximately 0.7 mm on the cured silicone rubber mold.
The mixture was heated at 200°C for 3 minutes to form a gel. Next, when this was cooled and the solidified polyvinyl chloride sheet was peeled off from the cured silicone rubber mold, a suede-like polyvinyl chloride sheet having an excellent suede feel on the surface was obtained.

Polyvinyl chloride paste composition Polyvinyl chloride resin (paste resin Zeon 121
Nippon Zeon Co., Ltd.) 100 parts Plasticizer (DOP) 60〃 Diluent (mineral spirits) 13〃 Epoxidized soybean oil 3〃 Stabilizer 2〃 Pigment (blue color) 6〃 Viscosity reducing agent (PEG-400 Sanyo (manufactured by Kagaku Kogyo Co., Ltd.) 1 The above composition had a nonvolatile content of about 93%, and its viscosity was measured to be about 500 cps (25°C).

Example 4 Using the same cured silicone rubber mold as in Example 1, 0.7 mm of a beige-colored polyurethane resin solution having the following composition was applied to the cured silicone rubber mold.
The coating was applied to a thickness of 100 mL and heated and solidified at 130°C for 5 minutes.
Next, after cooling it, apply adhesive to its surface,
After bonding a double-sided knitted base fabric made of 30 count rayon yarn, the laminate was peeled off from the cured silicone rubber mold. Next, a pale pink cloud pattern was applied to this surface using a gravure printing machine, and then a striped pattern was formed on the surface using an embossing group, resulting in an excellent suede feel. A suede-like urethane leather with a variety of designs and high added value was obtained.

Polyurethane resin solution composition Polyurethane resin (Crispon 3454 manufactured by Dainippon Ink & Chemicals Co., Ltd.) 20 parts Mixed solvent of IPA, toluene, and methyl cellosolve
80 parts Pigment (beige color) 8

Claims (1)

[Claims] 1 A material whose surface consists of a large number of dense napped short fibers is used as a prototype, and an uncured curable silicone rubber that is fluid at room temperature is applied to this surface so that the napped short fibers of the material are buried. Then, after curing the silicone rubber, a first step of manufacturing a cured silicone rubber mold by removing the material, and placing a plastic that is fluid at room temperature on the cured silicone rubber mold obtained in the first step. 1. A method for manufacturing a suede-like plastic sheet, which comprises a second step of applying a material, filling it into the micropores of a cured silicone rubber mold, and peeling off the plastic material after solidification.