| 摘要 |
<p>1,268,270. Laminates. SUMITOMO CHEMICAL CO. Ltd. 18 June, 1969 [21 June, 1968], No. 30766/69. Heading B5N. A process for producing a coloured laminated rubber article comprises preparing two blends of ethylene-propylene rubber, inorganic filler, colouring agent and cross-linking agent, semivulcanizing one of the blends (e.g. by heating at 120-200‹ C. for a short time) and vulcanizing the other, laminating the two blends, and vulcanizing the resulting assembly. The rubber may be an ethylene-propylene copolymer or an ethylene-propylene-non-conjugated diene terpolymer, specified dienes being 1,4-hexadiene, dicyclopentadiene, 5-methylene-2-norbornene, 5 - ethylidene - 2 - norbornene and 4,7,8,9- tetrahydroindene. The blends may also contain a plasticizer and a process oil. The degree of semi-vulcanization of the first blend is usually such that the rubber shows 300-500% of weight increase rate after immersion in benzene for 48 hours at 25‹ C. The vulcanized and semivulcanized blends may be adhered by heating at 140-200‹ C. in a press.</p> |
