JPH0644446A - Resin inserted metal coin to which impregnation printing is performed - Google Patents

Abstract

PURPOSE:To color the resin insert metal coin, and also, to use it under a severe condition without allowing its printed part to peel off by performing impregnation printing to one face or both faces of the surface of a thermoplastic resin part in the center part. CONSTITUTION:As for a thermoplastic resin 3, a crystalline resin is desirable in respect of impregnation printability, and for instance, a polyester resin, etc., such as a polyolefin resin, a polyamide resin, a polyacetal resin, polybutylene terephthalate, polyethylene terephthalate, etc., are given. Also, from the view- point of insert formability, impregnation printability, and durability as a coin, etc., it is desirable to use the polyacetal resin and the polybutylene terephthalate resin as an insert resin, and impregnation printing is performed to one face or both faces of the surface of a thermoplastic resin 3 part. The impregnation printing is executed by using a method by which for instance, special ink in which a sublimate dye is contained is used, a character, a symbol, etc., are printed directly to a formed part by pad printing, screen printing, etc., and thereafter, a heat treatment is executed, and the dye is infiltrated and fixed to the inside of the formed part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal coin used in a slot machine, a game machine or the like, in which a resin portion is formed in the central portion thereof and a resin insert metal is impregnated and printed on the surface of the resin portion. Regarding coins.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
The coins used for slot machines and game machines are
Like ordinary currency, all coins were made of metal (hereinafter referred to as metal coins). However, metal coins are easily worn, and metal powder may be generated due to this wear. Moreover, this metal powder adheres to the metal coins, and when handling it, the defects such as blackening hands and the like, and the metal coins with the metal powder entering the inside of the machine of the slot machine or the game machine may cause malfunction of these machines. There was concern that it might be the cause. This was unavoidable because game coins, by their very nature, were handled roughly. On the other hand, in recent years, it has been demanded that these game coins be provided with a design or a pattern on the surface thereof, and especially colored, but with conventional metal coins, printing means or the like cannot be used and the decorativeness is improved. It was scarce and was simply decorated with a stamp. In addition, recently
Although the technology for printing on metal has advanced and it is possible to apply monochromatic printing, as mentioned above, since game coins are handled roughly, printing is likely to fall off easily. Multicolor printing is also impossible, and it is extremely difficult to manufacture at a low cost what is practically usable. Further, it is possible to cover the entire surface of the game metal coin with ceramic and print it, but this also has a drawback such as cracking.

[0003]

In view of the above-mentioned conventional technique, the present inventor resinizes a part of a game coin and prints the resin part in order to provide a game coin with a surface decoration. The present invention has been completed as a result of investigating the resin component and the printing method particularly suitable for this application, paying attention to. That is, the present invention is a resin insert metal coin in which a resin part made of a thermoplastic resin is formed in the central portion, and one or both surfaces of the resin part of the resin insert metal coin is impregnated and printed.

The resin insert metal coin of the present invention will be described below. The resin insert metal coin of the present invention can be formed by a conventional insert molding method. FIG. 1 shows a sectional view of an example of a resin insert metal coin. In the present invention, the thermoplastic resin to be used is not particularly limited, but in general, a crystalline resin is preferable from the viewpoint of impregnating printability, for example, polyethylene, polyolefin resin such as polypropylene, polyamide resin, polyacetal resin, polybutylene terephthalate, Examples thereof include polyester resins such as polyethylene terephthalate. It is particularly preferable to use a polyacetal resin or a polybutylene terephthalate resin as the insert resin from the viewpoints of insert moldability, impregnation printability, durability as a coin and the like. Here, the polyacetal resin used in the present invention is a polymer compound having an oxymethylene group (--CH ₂ O) as a main constituent unit, and contains a small amount of other constituent units other than the polyoxymethylene homopolymer and the oxymethylene group. It may be a copolymer (including a block copolymer) or a terpolymer, and the molecule may have not only a linear structure but also a branched or crosslinked structure. Further, there is no particular limitation on the degree of polymerization or the like. Further, the polybutylene terephthalate resin is a polymer compound obtained by a polycondensation reaction with terephthalic acid or its ester-forming compound and 1,4-butanediol as the main components, and a generally known copolymerization component. It may be a polybutylene terephthalate copolymer contained. Further, in the present invention, known additives and / or fillers can be further added to the above-mentioned insert resin depending on the purpose, within a range that impregnating printability is not significantly impaired. For example, antioxidants, various stabilizers for improving weather resistance, lubricants, plasticizers, nucleating agents, flame retardants, release agents, antistatic agents, surfactants, etc. or glass fibers, metal fibers, potassium titanate, Fiber flakes such as glass flakes, glass beads, mica, talc, wollastonite, calcium carbonate, titanium oxide, alumina, silicon carbide, boron nitride, ceramics, metal powders, etc. is there. Also,
It is also possible to add a small amount of known synthetic resin, rubber or the like.

Next, impregnation printing is performed on one or both surfaces of the resin portion of the resin insert metal coin having a resin portion made of a thermoplastic resin formed in the central portion. The impregnation printing method in the present invention is also not particularly limited, a conventionally known method, for example, using a special ink in which a sublimable dye is kneaded, pad printing, characters directly on a molded article by a method such as screen printing, A method of permeating and fixing the dye in the ink to the inside of the molded article by printing symbols and the like and then heat-treating or printing letters and symbols on the release paper using the special ink and then printing the release paper Any method can be used, such as a method in which the dye is contained in the ink and permeated and fixed to the inside of the molded product by heat-pressing the product onto the molded product.

[0006]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Example 1 Molding of a resin insert metal coin A resin insert metal coin 1 (diameter 25 mm, thickness 1.5 mm) in which a resin portion 3 is formed in the central portion as shown in FIG. 1 by using polyacetal resin and polybutylene terephthalate resin.
Was molded. Impregnation printing method The above resin insert metal coin was degreased by ultrasonic cleaning in 1,1,1-trichloroethane and then dried.
Then, using the ink of SMX PBT (ink) F-1 / reducer liquid WKLTD = 10/1 manufactured by Toyo Ink Co., Ltd., the letters, symbols, etc. are directly printed on the resin part surface of the resin insert metal coin by the pad printing method. Printing was performed, heating was performed at 150 ° C. for 8 minutes, and baking was performed to allow the ink to permeate and fix inside the resin, and finally the surface was washed with a solvent and then dried. When the appearance of the evaluation print part was observed with the naked eye and a magnifying glass of 10 times, the print part was clear and there was no ink bleeding.
The printing state was not impaired even after processing for 240 hours in a thermo-hygrostat at 80 ° C and 95% RH. In addition, the sublimable dye component of the ink is permeated and fixed in the resin, and the sharpness of the printed part is almost impaired even in the wiping test with a solvent and the abrasion test with a plastic eraser at a pressure of 500 g for 10,000 times. There was no.

[0007]

As described above, in the resin insert metal coin of the present invention, the resin portion is formed in the central portion,
Since the resin part surface is impregnated and printed, it is possible to color the game coin, and the printed part does not come off, making it extremely practical as a decorative game coin used under harsh conditions. It is a thing.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a resin insert metal coin according to the present invention.

[Explanation of symbols]

 1 ... Resin insert metal coin 2 ... Metal part 3 ... Resin part

Claims (2)

[Claims] 1. A resin insert metal coin in which a resin part made of a thermoplastic resin is formed in the central portion, and one or both surfaces of the resin part of the resin insert metal coin is impregnated and printed. 2. The resin insert metal coin according to claim 1, wherein the thermoplastic resin is a polyacetal resin or a polybutylene terephthalate resin.