JPH0825223B2 - Method for manufacturing rubber product with gold pattern - Google Patents

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 a rubber product which has a vivid gold color pattern which is not easily erased by repeated contact with other objects. Here, the pattern is used in a broad concept including numbers and letters.

[0002]

2. Description of the Related Art For the purpose of imparting a commercial value to a rubber product, for example, a method of forming a gold pattern on the surface is practiced.

Conventionally, as a method of forming a golden pattern on the surface of a rubber product, natural rubber, emulsion-polymerized styrene / butadiene copolymer rubber, polybutadiene rubber, polyisoprene rubber and the like are compounded with appropriate parts by weight of a predetermined rubber compounding agent. The kneaded product was sheeted, a gold foil of an appropriate size was placed on the surface, and the gold foil was transferred by pressing with a mold having a convex pattern, and the mold was pressed so that the transfer surface was slightly recessed. The method of sulfurization was adopted.

[0004]

In the above-mentioned manufacturing method, a gold foil of an appropriate size is placed on the surface of the sheeted rubber molding, and the gold foil is transferred by pressing with a mold having a convex pattern, and then transferred. When the mold is pressed so that the surface is concave, the green strength of the unvulcanized rubber is small and the adhesiveness is large, so when the mold is pulled up and the mold itself is removed, its shape retention property is Due to the small size and the fact that the material adheres to the bottom surface of the mold, the outer peripheral edge of the recessed pattern collapses, and the appearance of the rubber product is impaired.

An object of the present invention is to overcome such drawbacks and to obtain a rubber product having a golden pattern having an excellent appearance.

[0006]

According to the present invention, a kneaded product comprising 100 parts by weight of a rubber having a small green strength, 20 to 40 parts by weight of a rubber having a large green strength, and other appropriate parts by weight of a compounding agent for a rubber is sheeted. ,
Place a gold foil of an appropriate size on the surface, press with a mold having a convex pattern, transfer only the gold foil on the lower surface of the convex pattern, and further press with the mold so that the transfer pattern surface is concave A method for producing a rubber product having a gold pattern is characterized in that the mold is removed and then vulcanized.

As the rubber having a small green strength, natural rubber, emulsion-polymerized styrene / butadiene copolymer rubber, polybutadiene rubber, polyisoprene rubber or the like is used as described above, and as the rubber having a large green strength, a thermoplastic rubber or a partial rubber is used. Crosslinked natural rubber and partially crosslinked styrene / butadiene copolymer rubber are used.

The thermoplastic rubber is so-called solution styrene / butadiene copolymer (bonded styrene content 18) which is block copolymerized in a hydrocarbon using an organic lithium catalyst.
The partially crosslinked natural rubber is, for example, a so-called SP smoked sheet obtained by mixing 80% by weight of raw latex with 20% by weight of vulcanized latex and coagulating and drying the mixture.
SP crepe, SP air dry sheet, etc. or these SP
PA-80, PA-57 and the like in a rubber-concentrated form are used, and the partially crosslinked styrene / butadiene copolymer rubber is, for example, a special styrene / butadiene copolymer copolymerized with divinylbenzene and having a bound styrene content of 23.5%. Rubber is used.

Rubber with a large green strength is 2
If it is less than 0 parts by weight, the green strength of the unvulcanized rubber kneaded product is insufficient and the shape retention is small, and the tackiness is large, and the outer peripheral edge of the recessed pattern collapses after embossing, which is the intended purpose of the present invention. On the other hand, when it exceeds 40 parts by weight, the plasticity of the unvulcanized rubber kneaded product becomes small, the surface of the sheeted molded product is roughened, and smoothness is not obtained, so that only a product having a poor commercial value can be obtained.

[0010]

【Example】

The sample Nos. In the above formulation table were sequentially kneaded, aged at room temperature for one day, and then sheeted to a thickness of 1.0 mm. A gold foil (Shine foil SH65 # 1 manufactured by Nakai Kogyo Co., Ltd.) with a size of 20 mm × 70 mm was placed on the surface and TH
Press with a mold having convex letters of OMMCAN (temperature 80 ° C., air pressure 2 kg / cm ² , time 1 second), and fill the gold foil and sheet to the same level with the gold foil, The gold foil on the part was removed and only the gold letters were transferred. Subsequently, with the same mold as above (under the same conditions as above), the press metal letters were recessed by 0.25 mm.

[0012] Then, indirect vulcanization (temperature 130 ° C., time 6
0 minutes, air pressure 2 kg / cm ² ) was applied. The product of the trial number inventions 1 and 2 obtained by the above-mentioned manufacturing method was particularly suitable for the lower edge tape for shoes.

[0013]

EFFECTS OF THE INVENTION It was possible to continuously and smoothly obtain a rubber product in which the outer periphery of the gold pattern is clear and the other surface is smooth.

Claims (1)

[Claims] 1. A rubber 10 having a small green strength.
0 parts by weight, rubber with large green strength 20-4
The kneaded product consisting of 0 parts by weight and other required parts by weight of the rubber compounding agent is appropriately weighted, and a gold foil of an appropriate size is placed on the surface of the sheet and pressed by a mold having a convex pattern to form a lower surface of the convex pattern. The method for producing a rubber product having a gold-colored pattern, characterized in that only the gold foil is transferred, and further, the transfer pattern surface is depressed by the mold so that the mold is removed and vulcanized.