JP3056609B2 - Nubuck-like artificial leather with excellent design appearance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an artificial leather having a nubuck tone and, more particularly, to an artificial leather having a colored metallic powder pigment coated on its surface and having an excellent appearance.

[0002]

2. Description of the Related Art Conventionally, artificial leather comprising a fibrous material and a polymer elastic material has been widely used as a substitute for leather in applications such as shoe upper materials, shoe accessory materials, clothing main materials, clothing parts materials, and bag materials. It is now an indispensable material for these applications. These artificial leathers are roughly classified into a suede type, a nubuck type, and a silvered type according to the surface morphology as well as the classification of the natural leather. Among them, the natural leather nubuck type has the fine touch and appearance, and has been treated as the most luxury item. Attempts to express these high-quality appearances on artificial leather have been repeated in the past.

In order to express the luxurious feel of these nubuck type natural leathers as artificial leather, a polymer elastic body is provided to the fiber made of ultrafine fibers, and the ultrafine fibers having a short surface are mixed with the polymer elastic body. Structures with different structures have been proposed. However, these artificial leathers, the color fastness of the fiber,
There are many technical difficulties such as dye transfer and adjustment of the fiber length of the surface, and the cost is high.

[0004] Further, as artificial leather, there has been proposed an artificial leather in which a polymer elastic body is formed into a vertical hole and a dense layer on the surface is removed to open a hole. This is technically easier than the structure in which the surface is made of a mixture of a short microfiber and a polymer elastic material, and is advantageous in terms of cost,
Since the surface has an open-pore structure made of only a polymer elastic material, it is difficult to obtain the elegance of natural nubuck in appearance.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a surface appearance which is a drawback of a nubuck tone artificial leather in which the above-mentioned elastic polymer is formed into a vertical hole and the dense layer on the surface is removed to open the hole. The object of the present invention is to provide a nubuck-like artificial leather having improved surface elegance and significantly improved surface elegance as compared with the prior art.

[0006]

According to the present invention, a colored porous polyurethane layer having a thickness of 50 μm to 400 μm is formed on one surface of a substrate made of fibrous material or fibrous material and polymer elastic material. A nubuck-like artificial leather having excellent design appearance, characterized in that the artificial leather has a surface coated with a colored metallic powder pigment.

The fibers constituting the artificial leather of the present invention are:
It is a woven fabric, a knitted fabric, a nonwoven fabric, or the like made of conventionally known natural fibers, recycled fibers, and synthetic fibers. Cotton as natural fiber,
Examples include hemp, wool, silk, and the like. Examples of the regenerated fibers include rayon and acetate. Examples of the synthetic fibers include polyester, nylon, and acrylic. For synthetic fibers, it is preferable to use ultra-fine fibers of 0.5 denier or less, preferably 0.01 denier to 0.2 denier, from the viewpoint of enhancing the texture and elegance of the artificial leather of the present invention. Incidentally, the basis weight of the fibrous, preferably ^{60g / m 2 ~500g / m 2} , more preferably ^{100g / m 2 ~350g / m 2} , the thickness preferably 0.3 mm to 3 mm, more preferably 0. 5
mm to 2.5 mm.

[0008] The polymer elastic body of the present invention is a polymer elastic body used as a conventionally known substitute for leather. For example, polyurethane, polyurea, polyurethane polyurea, styrene-butadiene rubber, acrylonitrile-butadiene rubber and the like, these are aqueous emulsion,
Or after impregnating the fiber as an organic solvent solution,
It is solidified to form a substrate composed of a fibrous material and an elastic polymer.

As the colored porous polyurethane layer formed on one surface of the base made of the fibrous material or the fibrous material and the polymer elastic body, any of the conventionally known polyurethanes can be applied. Can be applied. For example, after coating a solution of polyurethane in an organic solvent on one surface of a fibrous material or a substrate made of fibrous material and a polymer elastic material, solidification is a non-solvent of polyurethane and miscible with an organic solvent in which polyurethane is dissolved. A method of causing coagulation in a bath, or a W / O type emulsion obtained by finely dispersing water in an organic solvent solution or dispersion of polyurethane, on one side of a substrate made of fibrous material or fibrous material and polymer elastic material And then coagulating the polyurethane by selectively evaporating the organic solvent.

[0010] The thickness of the colored porous polyurethane layer of the present invention is 50 µm to 400 µm. This thickness is necessary for obtaining abrasion resistance, surface smoothness, cushioning properties, and voluminous feel. If the thickness is less than 50 μm,
A fibrous texture appears on the surface, making it difficult to obtain a smooth feeling on the surface, and at the same time, the grinding amount is limited when grinding the dense surface layer of the colored porous polyurethane layer, which is not preferable. On the other hand, when the thickness exceeds 400 μm, it is not preferable in that rubber-like artificial leather is obtained and productivity is reduced.

In the present invention, these colored porous polyurethane layers are not intended to limit the present invention since the purpose is to give a nubuck appearance, but it is preferable that the colored porous polyurethane layers have a vertical hole shape. Since the outermost surface of the colored porous polyurethane layer becomes dense in any of the conventional methods, it is necessary to grind this dense layer to open holes. Therefore, in order to facilitate the surface grindability and obtain a good nubuck appearance, a porous material having a vertical hole shape is preferable. The porosity of the colored porous polyurethane layer, that is, the apparent density, is preferably 0.35 in view of the grindability of the dense layer on the outermost surface and the ability to impart an uneven pattern.
g / cc to 0.55 g / cc, more preferably 0.3
7 g / cc to 0.45 g / cc. If the apparent density is too low, the abrasion resistance of the obtained product is hardly obtained, while if it is too high, the grindability or the imparting property of the uneven pattern described later is inferior.

[0012] The colored porous polyurethane layer is of course colored in various colors. Examples of the coloring agent include dyes and pigments, and are preferably pigments in terms of light resistance and color transfer when used as a final product. Also,
In the present invention, a pattern used for ordinary artificial leather can be applied by embossing. As the pattern of the pattern, various conventional patterns such as a pore tone, a blood tone tone, or a combination thereof are used. As a method of applying a pattern to the colored porous polyurethane layer, a method of heating the pattern roll to the softening temperature of the polyurethane and applying a pressure treatment to the colored porous polyurethane layer is generally used. A method in which the pressing pressure is increased by pressing can also be adopted. In any case, it is important to accurately transfer the pattern of the roll handle to the colored porous polyurethane layer in order to obtain a high-grade appearance. The process of applying the pattern may be before or after grinding the dense layer on the surface of the colored porous polyurethane layer.
However, it should be noted that if embossing is performed after grinding, the diameter of the opened hole becomes small and the nubuck feeling may be lost.

For the grinding of the surface dense layer of the colored porous polyurethane layer, a grinder using sandpaper is used. Although the surface condition varies somewhat depending on the number of meshes and the grinding speed of the sandpaper, the porous condition of the colored porous polyurethane layer is basically dominant. The opening diameter of the hole varies depending on the amount to be ground, and the appearance and feel of the surface may be different. Therefore, it is desirable to make the amount to be ground constant.

In the present invention, a colored metallic powder pigment is applied to the surface of the above nubuck artificial leather. As the colored metallic powder pigment, those conventionally manufactured in various types can be used. As a typical example, a colored synthetic resin film is formed on a carrier, a metal such as aluminum is vapor-deposited on the surface, the carrier is removed, and pulverized. These are mixed into a conventional surface-forming paint for artificial leather and applied as a metallic paint on the surface of nubuck-like artificial leather having holes. The amount of colored metallic pigment applied to the surface can be adjusted by adjusting the amount of colored metallic pigment by vacuum evaporation of metal such as aluminum in metallic paint. Various simplicity expressions such as stardust are possible. Since these elegant expressions are applied to the nubuck-like surface, elegance not seen in conventional artificial leather can be expressed. Although colored metallic paint of the pigment is not particularly limited, it is preferably 0.1g / m ² ~5g / m ² approximately.

In the present invention, the hue of the colored porous polyurethane layer and the hue of the colored metallic powder pigment applied to the surface thereof are differently combined, so that a deeper hue can be expressed. A similar color scheme (eg, green and blue), a complementary color scheme, or a dark color (eg, black) primary color scheme,
Various combinations are possible and each can be expressed brilliantly with a deep hue.

When a colored metallic powder pigment (hereinafter sometimes referred to as “metallic paint”) is applied to the surface of the colored porous polyurethane layer having pores and dried, the organic solvent constituting the metallic paint is used to form pores. Extreme changes in the opening diameter due to melting or the like must be avoided. If the opening diameter of the hole is too small, the nubuck feeling that is the object of the present invention cannot be obtained. Therefore, the organic solvent that constitutes the metallic paint is
Those having a small dissolving power for the colored porous polyurethane layer are preferred. Specific examples of the organic solvent include methyl ethyl ketone, toluene, isopropyl alcohol, and a mixed organic solvent of these organic solvents and dimethylformamide having a high dissolving power for polyurethane.

A specific example of a method for obtaining a nubuck-like artificial leather coated with the metallic paint of the present invention will be described. That is, after impregnating a fibrous material such as a woven fabric, a knitted fabric, or a nonwoven fabric with an organic solvent solution of a polymer elastic material such as a polyurethane and coagulating and drying, a dimethylformamide solution of a polyurethane colored with a pigment or a dye is used. After coating, water immersion coagulation, washing, and drying, an artificial leather substrate having a colored porous polyurethane layer having a thickness of 50 μm to 400 μm is prepared, and then a pattern is applied by embossing. Next, after the surface dense layer of the colored porous polyurethane layer is ground by a grinder, a metallic paint is applied and dried by a coater. By way of example, such a method produces the nubuck tone artificial leather of the present invention having an excellent design appearance.

[0018]

The present invention will now be described more specifically with reference to examples. In the Examples, “parts” and “%” are based on weight. Example 1 <Preparation of Substrate-1> Weight 300 g / m ² , thickness 1.0 m
m on a single side of an impregnated base cloth impregnated with a 13% red-colored polyurethane-dimethylformamide solution [Dilac L3440 red; used by Dainippon Ink and Chemicals, Inc.] 1
An 8% concentration of a red-colored polyurethane-dimethylformamide solution was coated with [Dilac L3440 red as a pigment; used by Dainippon Ink and Chemicals, Inc.] with a basis weight of 650 g / m ² , followed by immersion coagulation, washing with water and drying. Thus, a red base-1 was prepared. The obtained red base-1 had a fibrous layer thickness of 1.0 mm and a colored porous polyurethane layer thickness of 280 μm.

<Patterning, Surface Grinding, Application of Metallic Paint> The colored porous polyurethane layer of the red base-1 was coated with 17
After applying a handle with an embossing roll of a blood tone tone pattern heated to 0 ° C., the convex portion of the colored porous polyurethane layer is ground with a grinder in which a 200 mesh sandpaper is wound around the roll, and the red color of the polyurethane layer is obtained. And the pores were opened. A blue metallic paint-1 having the following composition was applied to the surface with a gravure coater (using a 110 mesh roll) and dried. The obtained artificial leather (referred to as artificial leather-1) has a complex surface represented by red and blue, looks purple overall, looks like glittering stardust, and has a nubuck-like appearance. Because it has the elegance and splendor that never existed in conventional artificial leather or conventional leather substitutes, it was valuable for applications such as secondary materials for shoes, secondary materials for clothing, or bags. .

(Paint-1) ELGY; BLUE # 200 2.5 parts [Silver pigment, manufactured by Oike Kogyo Co., Ltd.] Resamine NE8855-20N 90 parts [Manufactured by Dainichi Seika Kogyo Co., Ltd.] Haurac A1008 20 parts [ Dainippon Ink & Chemicals, Inc.] Isopropyl alcohol 80 parts Toluene 60 parts Dimethylformamide 10 parts

Example 2 <Preparation of Substrate-2> Weight 550 g / m ² , thickness 1.5 m
m, a 13% concentration of a blue-colored polyurethane-dimethylformamide solution in a nonwoven fabric made of ultrafine fibers that have polyester as an island component and polyethylene as a sea component [island component / sea component (weight ratio) = 50/50]. [Dailac L3480 blue as a pigment; Dainippon Ink and Chemicals, Inc.
650 g / m ^{2 of} 18% blue colored polyurethane-dimethylformamide solution [Dilac L3480 blue; used by Dainippon Ink and Chemicals, Inc.] on one surface of the impregnated base fabric impregnated with After being covered with water, solidified by water immersion, washed with water, and dried, the polyethylene constituting the sea component of the fiber is extracted with toluene, so that the fiber constituting the nonwoven fabric is ultrafine-processed to obtain a blue base-2. Created. The resulting blue base-2 was made of ultrafine fibers having an average fiber denier of 0.02 denier, the fiber layer had a thickness of 1.0 mm, and the colored porous polyurethane layer had a thickness of 280 μm. It had a soft texture.

<Patterning, Surface Grinding, Application of Metallic Paint> The colored porous polyurethane layer of the blue substrate-2 was
After applying a pattern with an embossing roll of a pore-like pattern heated to 0 ° C., the convex portion of the colored porous polyurethane layer is ground by a grinder in which a 200 mesh sandpaper is wound around the roll, and the blue color of the polyurethane layer is obtained. And the pores were opened. The blue metallic paint-1 prepared in the example was applied to the surface with a gravure coater (using a 110 mesh roll) and dried. Obtained artificial leather (artificial leather-
2) has the elegance and splendor that has never been seen with conventional artificial leather or conventional leather substitutes because its surface is like blue and glittering stardust and has a nubuck appearance. It was valuable as a secondary material for shoes or a secondary material for clothing.

Example 3 The colored porous polyurethane layer of the blue substrate-2 prepared in Example 2 was patterned with an embossing roll having a pore-like pattern heated to 170 ° C., and then a 200-mesh sandpaper. Of the colored porous polyurethane layer was ground using a grinder wound around a roll to develop a blue color in the polyurethane layer and open holes. Silver paint-2 prepared with the following composition was applied to the surface with a gravure coater (using a 110 mesh roll) and dried. The obtained artificial leather (referred to as artificial leather-3) has a bluish surface, exhibits a snow-like silver luster on the entire surface, and has a nubuck appearance. Therefore, the conventional artificial leather or the conventional leather is used. The alternative was a combination of unprecedented elegance and splendor, and was valuable as a point material for clothing and handbags.

(Paint-2) ELG; Silver # 200 10 parts [Oike Kogyo Co., Ltd., silver pigment] Resamine NE8855-20N 90 parts [Dainichi Seika Kogyo Co., Ltd.] Haulac A1008 20 parts [Dainippon Ink Chemical Industry Co., Ltd.] Isopropyl alcohol 80 parts Toluene 60 parts Dimethylformamide 10 parts

[0025]

According to the present invention, a nubuck tone artificial leather having improved surface elegance, which is a drawback of the nubuck tone artificial leather, and having much improved surface elegance as compared with the conventional one can be obtained.

──────────────────────────────────────────────────続 き Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) D06N 3/00-3/18 B32B 27/12

Claims (2)

(57) [Claims] 1. A substrate having a thickness of 50 μm to 400 μm on one surface of a substrate made of fibrous material or fibrous material and elastic polymer.
A colored porous polyurethane layer is formed, and the surface is a nubuck-like artificial leather in which holes are exposed and opened, and the surface of the artificial leather is coated with a colored metallic powder pigment. Nubuck-like artificial leather. 2. The artificial nubuck leather according to claim 1, wherein the hue of the colored porous polyurethane layer is different from the hue of the colored metallic powder pigment.