A golf ball 2 includes a core 4, a mid layer 6, and a cover 10. The core 4 includes a center 16, a first envelope layer 18, and a second envelope layer 20. The first envelope layer 18 is formed by a first rubber composition being crosslinked. The second envelope layer 20 is formed by a second rubber composition being crosslinked. The first rubber composition and/or the second rubber composition include: a base rubber; a co-crosslinking agent; a crosslinking initiator; and an acid and/or a salt. The co-crosslinking agent is (1) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms; and/or (2) a metal salt of an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms.
An object of the present invention is to provide a golf ball having an excellent flight performance on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, (c) a crosslinking initiator, and (d) an unsaturated fatty acid and/or a metal salt thereof excluding an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof, and provided that the rubber composition further contains (f) a metal compound if only an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms is present as (b) the co-crosslinking agent.
CURED PRODUCT OF GOLF BALL RUBBER COMPOSITION AND GOLF BALL
申请人:Sumitomo Rubber Industries, Ltd.
公开号:EP3875529A1
公开(公告)日:2021-09-08
An object of the present invention is to provide a cured product of a golf ball rubber composition for constituting a golf ball having excellent shot feeling on both driver shots and approach shots. The present invention provides a cured product of a golf ball rubber composition, wherein the golf ball rubber composition contains (a) a base rubber, (b) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, and (c) a crosslinking initiator, and a product (hardness x (tanδ-80 - tanδ0)) obtained by multiplying a slab hardness of the cured product of the golf ball rubber composition in Shore C hardness by a difference (tanδ-80- tanδ0) between a loss tangent of the cured product of the golf ball rubber composition at -80 °C (tanδ-80) and a loss tangent of the cured product of the golf ball rubber composition at 0 °C (tanδ0) is 28.0 or more.
Rubber composition, crosslinked rubber molded product and golf ball
申请人:Dunlop Sports Co. Ltd.
公开号:US10293215B2
公开(公告)日:2019-05-21
An object of the present invention is to provide a rubber composition from which a crosslinked rubber molded product excellent in the resilience performance can be obtained. The present invention provides a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent and (c) a crosslinking initiator, wherein (b) the co-crosslinking agent contains a complex represented by a general formula (1).
[In the formula (1), M is a metal atom, and L is a carboxylate represented by the general formula (2). In the formula (2), R is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms or an alkynyl group having 2 to 18 carbon atoms, and the dotted line shows a resonance structure. In the formula (1), a plurality of R may be identical to or different from each other, and at least one of R is the alkenyl group having 2 to 18 carbon atoms or the alkynyl group having 2 to 18 carbon atoms.]
An object of the present invention is to provide a method for obtaining a golf ball having excellent impact durability. The present invention provides a method for producing a golf ball, comprising a first step of kneading (a) a base rubber, (b) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, (c) a crosslinkable compound having two or more polymerizable unsaturated bonds in a molecule thereof, and (d) a crosslinking initiator to prepare a core rubber composition; a second step of producing the spherical core from the core rubber composition at a molding temperature in a range from 100° C. to 150° C.; and a third step of molding the at least one cover layer covering the spherical core on the spherical core.