JPS6216832B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a sheet with good three-dimensional effect. More specifically, it relates to a method for producing a sheet with a good three-dimensional effect by treating the surface of a flexible sheet (hereinafter referred to as the substrate) having a polymer layer with an uneven pattern with a roll under specific conditions. be.

Sheets made of a fibrous base material and a polymer layer are often used for interior materials, shoes, bags, cases, balls, belts, etc. The appearance of the sheet, especially the color and gloss of the surface, together with the properties of the substrate, are important factors that influence the commercial value. In the past, the color and gloss of the surface of sheets were often uniform, but recently, sheets with uneven patterns and colors or glosses that have different color or gloss on the concave and convex parts of the surface are becoming more and more popular. Due to the synergistic effect with gloss, it looks more three-dimensional and has become popular because it gives a sense of luxury.

A method for obtaining a sheet having such an appearance is to spray or gravure print an ink of an arbitrary composition on the surface of a substrate having an uneven pattern so as to create a color difference or a gloss difference along the uneven pattern, and a method for printing the substrate. A commonly used method is to apply an arbitrary polymer composition having poor abrasive properties to the surface of the substrate, and then polish the polymer layer with a special stone or cloth.

Among these, the spray method is a method often used for natural leather, and is effective even if the depth of the uneven pattern on the substrate surface is relatively small, but it has poor workability and productivity and is unsuitable for mass production.

On the other hand, in the normal gravure method, a roll with ink attached to the substrate is brought into contact with a pressure above a certain level, and at the same time, the direction of rotation of the roll, the feeding direction of the substrate, and the peripheral speed of the roll and the feeding speed of the substrate are both controlled to be the same. This method transfers ink to the substrate, and is effective when the depth of the uneven pattern on the substrate surface is large, that is, when the depth of the uneven pattern is large, that is, it is effective for deeply textured products of about 200μ or more, but it is effective for products with shallow textures of less than 200 μm. In this case, the concavo-convex pattern disappears due to pressure, so ink cannot be applied selectively only to the concave portions, and it is therefore impossible to obtain a sheet with a desired three-dimensional effect.

Further, the method of polishing with an abrasive as described above is usually used manually for final products such as shoes and bags, and is hardly applied to mass production. This method also has drawbacks such as it is extremely difficult to obtain a product with a difference in color or gloss that closely follows the sheet surface with shallowly grained products, it takes time to polish, and stains are likely to occur. are doing.

Therefore, it is possible to obtain a product that does not have such operational or production defects and has a shallow uneven pattern on the sheet surface, that is, even if it is a shallowly grained product, it faithfully follows the uneven pattern and has a clear difference in color or gloss. This was a major issue for everyone involved.

As a result of extensive research into finishing agents and finishing methods, the present inventors found that there is a difference between the feeding speed of a substrate having an uneven pattern and the peripheral speed of an ink application roll (hereinafter referred to as a contact roll) to which ink is attached. By providing a speed difference, even if the depth of the uneven pattern on the surface of the substrate is shallow, ink can be selectively attached only to the concave portions of the substrate due to the force caused by the speed difference, and the color or gloss can be faithfully applied along the uneven pattern. It has been found that sheets with sharp differences can be obtained very easily.

In other words, the present invention provides a sheet with a very good three-dimensional effect regardless of the uneven pattern of the substrate by operating a specific substrate and a contact roll under specific conditions. For the first time, it became possible to produce products with a high-class feel and high commercial value with good workability and productivity.

First, the substrate in the present invention is a flexible sheet consisting of a fibrous base material and a polymer layer or only a polymer layer, and has an uneven pattern on its surface, and is a so-called silvered leather-like sheet-like material. The fibrous base material is a sheet-like material mainly composed of fibers such as nonwoven fabric, woven fabric, knitted fabric, etc., which is optionally impregnated and coagulated with a polymer as a binder. Usual fibers can be used, including cotton, linen,
In addition to individually spun fibers such as wool, rayon, acetate, nylon, polyester, polyacrylonitrile, vinylon, and polyolefin,
Any mixture thereof or composite spun fibers can be used. As the binder optionally added to the above-mentioned fibrous base material, any binder that is generally used for synthetic leather etc. can be used, for example,
Natural rubber, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, polyvinyl chloride, polyurethane, other synthetic rubbers, or mixtures thereof are used. These binders are applied in a solution, emulsion, or other form as required by an impregnation method, a coating method, or the like. The amount of adhesion is usually within 150% of the fiber.

A polymer coating layer is formed on one side of the fibrous base material. The coating layer corresponds to the grain surface of ordinary leather, and is preferably porous in view of texture, creases, physical properties, etc. Examples of polymers include polyurethane, acrylonitrile-butadiene copolymer, polyvinyl chloride,
Although polyamide and the like can be used, polyurethane elastomer is particularly preferred. The polymer may contain fillers, softeners, stabilizers, antistatic agents, pigments, dyes, blowing agents, coagulation regulators, etc. as necessary, as well as polymers with good compatibility in the solution state, such as polyester. Vinyl chloride, polyvinyl acetate, polyvinyl formal,
Polyacrylic acid resin, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, etc. can be mixed. Although a coating method is preferred as the method for applying the polymer solution to the fibrous base material, a polymer coating layer may be separately prepared and bonded. Further, as the substrate of the present invention, a porous or non-porous sheet consisting only of the same kind of polymer as the above-mentioned coating layer can also be used.

The substrate may be suitably colored or may further have a surface layer made of a polymer on its surface. The surface of the substrate needs to have a different color or gloss from the ink to be applied next. Further, in the present invention, it is an essential condition that an uneven pattern exists on the surface of the substrate. This uneven pattern can be obtained by forming the surface of the substrate on a support having an arbitrary uneven pattern, or by embossing a desired pattern.
In the conventional method, the depth of this uneven pattern is a major factor that affects the three-dimensional appearance of the product, and it was only effective for deeply grained products of about 200μ or more, but the present invention is effective only for deeply grained products. Of course, it can be used for products with shallow grains of 50μ or less without any problems, and products with shallow grains of about 10μ can also be used.

Next, the surface of the substrate is rotated at a peripheral speed different from the feed speed of the substrate, brought into contact with a contact roll on which ink has adhered, and the ink is applied only to the concave portions of the substrate and then dried. Either a regular gravure roll or a flat roll can be used as the contact roll, but
The former is particularly preferred since it is easy to adjust the amount of ink deposited.

The ink used is a polymer composition that has a different color or gloss than the surface of the substrate, and includes polymers commonly used for leather, such as polyurethane elastomer, cellulose nitrate, nylon, polyamino acid resin, and polyester. It is a solution containing vinyl chloride, polyacrylic acid resin, etc., and additives to obtain the desired product, such as coloring agents, matting agents, metallic agents, pearling agents, fluorescent agents, etc. This ink also contains additives to improve physical properties, such as anti-yellowing agents, as needed.
Antioxidants, plasticizers, etc. may be mixed.

In this ink application operation, the contact pressure and contact area between the substrate and the contact roll, and the relative speed between the substrate and the contact roll are important. The contact pressure between the substrate and the contact roll ensures that the uneven pattern on the surface of the substrate does not disappear. Moreover,
The feeding speed of the substrate and the circumferential speed of the contact roll must be different, that is, the speed must be kept within a range that does not cause any problem for the substrate to slip on the contact roll, especially for shallowly textured products. In addition, in order to completely infiltrate the ink into the concave portions of the substrate, the substrate and the contact roll should be in surface contact with a large contact area, and the speed difference between the feeding speed of the substrate and the circumferential speed of the contact roll should generally be large. . In particular, good sheets can be obtained when the peripheral speed of the contact roll is higher than the feed speed of the substrate. Generally, the speed should be adjusted so that the speed ratio between the circumferential speed of the contact roll and the feeding speed of the substrate (peripheral speed of the contact roll)/(feeding speed of the substrate) is about 1.1 to 10. It is not necessary to explain that the structure of the present invention is not achieved as the speed ratio approaches 1 when the feeding direction of the substrate and the rotational direction of the contact roll are in the same direction. If the speed ratio is less than 1, ink smearing may occur even if the purpose of selectively applying only the recessed portions is achieved. Furthermore, it is generally not industrially possible for the speed ratio to be extremely large, exceeding 10. The preferred speed ratio is about 1.5 to 5. Further, appropriate finishing treatment may be applied as necessary. The sheet obtained in the above manner had an extremely good three-dimensional effect, a luxurious feel, and a high commercial value due to the synergistic effect of the uneven pattern and the color or gloss difference.

The present invention will be specifically described below with reference to Examples. Note that all percentages in the examples are based on weight.

Example 1 Polyhexamethylene adipate glycol, ethylene glycol, diphenylmethane-4・4'-
10% polyurethane elastomer made of diisocyanate, 2% polyvinyl chloride, 1% titanium oxide
A polyester non-woven fabric was impregnated with a solution consisting of 87% dimethylformamide and 87% dimethylformamide, and the same solution was applied on top of this to a solid content of 70g/m ² , and then soaked in an aqueous solution containing 40% dimethylformamide at 40°C for 30 minutes.
After immersion for a minute, solvent removal and drying were performed. This was then coated with 5% polyurethane elastomer of the same type as above, 2% polyvinyl chloride, and Lanyl Brown.
3R (manufactured by Sumitomo Chemical KK) 1.5%, Lanyl Yellow
G (manufactured by Sumitomo Chemical KK) 1.5% dimethylformamide 26%, acetone 31% and cyclohexanone 33
% solution to a solid content of 2 g/ ^m2 , and using an embossing roll,
A base material [] was manufactured by stamping a liquid skin texture of 82 μm. In addition, 5% polyurethane elastomer of the same type as above, 2% polyvinyl chloride, Lanyl Brown
3R (manufactured by Sumitomo Chemical KK) 2%, Irgalan Blue
RLE (manufactured by CiBa-Geigy) 1%, dimethylformamide 25%, acetone 29% and cyclohexanone
A gravure roll (contact roll) having 200 meshes of 23 μ deep grooves in a lattice pattern with 15 g/ ^m2 of solution from 36% applied was rotated at a circumferential speed of 25 m/min, and the substrate [] was placed 15 cm in the length direction on this roll. The sheet (A) was produced by passing it through the sheet at a speed of 10 m/min in the same direction as the rotational direction of the contact roll while making light surface contact, and then drying it. In this product, the concave portions of the skin texture were darker in color than the convex portions, giving an extremely three-dimensional color impression and a high-class feel. On the other hand, the above-mentioned ink was applied to the substrate by the conventional gravure method instead of the contact roll method and dried to obtain a sheet (B). Like the base material, this product had almost uniform color and almost no three-dimensional color appearance.

Example 2 6% polyurethane elastomer consisting of polytetramethylene glycol, ethanolamine, diphenylmethane-4,4'-diisocyanate and a phthalocyanine blue pigment (Dainichiseika Co., Ltd. Made by Industrial KK) 2
%, dimethylacetamide 32%, dioxane 28%
and 32% methyl ethyl ketone was applied at a solid content of 60 g/m ² and dried. Next, a raised nylon woven fabric was adhered to this surface with cross-linked polyurethane, and the release paper was peeled off to obtain a substrate.
In addition, 4% cellulose nitrate, 4% dibutyl phthalate
The substrate [ ] was treated in the same manner as in Example 1 using a solution consisting of 1% fine-particle silicon oxide and 91% thinner to obtain sheet (c). In this item, only the concave portions of the rough fabric pattern were matted, giving it an extremely good three-dimensional effect and a luxurious feel. When a bag was made using this method, it had a much higher commercial value than the base made using the conventional method.

Claims (1)

[Scope of Claims] 1. Applying ink to the surface of a flexible sheet having a polymer layer provided with an uneven pattern using a roll, and selectively adhering any ink only to the concave portions of the uneven pattern. A method for producing a sheet with good three-dimensional effect, characterized in that the operation is performed so as to provide a speed difference between the feeding speed of the flexible sheet and the peripheral speed of an ink application roll (hereinafter referred to as contact roll). 2. The sheet manufacturing method according to claim 1, wherein the peripheral speed of the contact roll is higher than the feeding speed of the flexible sheet. 3. The method for producing a sheet according to claim 1 or 2, wherein the contact between the flexible sheet and the contact roll is surface contact. 4. The method for producing a sheet according to claim 1, wherein the contact roll is a gravure roll. 5. The method for producing a sheet according to claim 1, wherein the contact roll is a flat roll. 6. The method for producing a sheet according to claim 1, wherein the ink is a polymer solution containing a colorant and/or a matting agent. 7. The method for producing a sheet according to claim 1, wherein the flexible sheet is a silvered leather-like sheet consisting of a fibrous base material and a polymer layer.