Method of fabricating an eraser
Abstract
Abstract A method of fabricating an eraser which contains a main basic material of low crystallizable polyolefin thermoplastic elastomer and normal synthetic rubbers having no hard segment for performing a crosslinking effect, namely, any one or more of chlorinated polyethylene, ethylene-propylene terpolymer, ethylene ethyl acrylate, ethylene-vinyl acetate copolymer, atactic polypropylene, styrene-butadiene rubber, nitrile rubber and the like. The thermoplastic elastomer exhibits similar properties to vulcanized rubber without particular vulcanizing operation and crosslinking reaction. In case that less than 40 parts by weight of the elastomer is contained in the eraser, the composition does not form an eraser, while in case that higher than 100 parts by weight of the elastomer is contained in the eraser, the composition incorporates excessive rubber-like properties. The method comprises the steps of mixing and kneading 50 to 800 parts by weight of factice, 0 to 500 parts by weight of filler and predetermined amount of pigment which 40 to 100 parts by weight of the low crystallizable polyolefin thermoplastic elastomer. Thus, the eraser is remarkably improved in the properties such as resistances to deterioration by aging, exposure to sunlight, migration of plasticizer, and tearing strength by its metallic band.
Inventors
- 👤 Takamasa Kawakubo
- 👤 Kiyosi Hirasawa
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
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