| 摘要 |
1312816 Golf balls DUNLOP HOLDINGS Ltd 20 July 1970 [24 July 1969] 35016/70 Heading A6D [Also in Division C3] Unitary golf balls, or cores for covered golf balls, are moulded from compositions comprising (1) a rubber having a glass-transition temperature of not more than -50‹C, particularly cis-polybutadiene, (2) tetramethylolmethane tetramethacrylate, (3) a polymerisation initiator, e.g. an organic peroxide, and (4) a filler, e.g. silica or particulate urea- or melamine-formaldehyde resin. Some of the exemplified compositions also contain lead carbonate. For covered balls using a core made from the above composition, numerous cover materials are listed, and in a specific Example the cover is made from 95 parts ethylene/ methacrylic acid (90.5/9.5) copolymer in which 55% of the acid is present as sodium salt, 5 parts ethylene/vinyl acetate (72/28) copolymer and 400 parts of TiO 2 . |
