Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core, and at least one layer of a cover formed on the core, wherein at least one of the layers of the core is formed by vulcanizing and press-molding a rubber composition having (a) a base rubber comprising polybutadiene rubber containing a cis-1,4-bond of not less than 80% in microstructure and having a molecular weight distribution (Mw/Mn) of 1.2 to 2.0, (b) a co-crosslinking agent, and (c) an organic peroxide.

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core, and at least one layer of a cover formed on the core, wherein at least one layer including the inmost layer of the core is formed by vulcanizing a rubber composition comprising a base rubber, a co-crosslinking agent, a vulcanization initiator and a filler, the core has a center hardness in JIS-C hardness of 40 to 60, a surface hardness in JIS-C hardness of 80 to 95 and a hardness difference (B?A) between a hardness in JIS-C hardness at a distance of 5 mm from the center point of the core (B) and the center hardness (A) of not less than 1 to less than 10.

Abstract: The present invention provides a solid golf ball which gives a superior shot feeling to the golfer and exhibits stabilized repulsion performance when it is hit at any head speed. The solid golf ball of the present invention comprises a core containing at least one layer which is molded by vulcanizing the rubber composition including: (a) a base rubber, (b) a co-crosslinking agent, (c) an organic peroxide, and (d) a polysulfide compound represented by the formula: wherein at least one of R1 to R5 and at least one of R6 to R10 are each Br, and n is an integer not less than 2.

Abstract: The present invention provides a solid golf ball which imparts a superior shot feeling to the golfer and exhibits stabilized repulsion performance when it is hit at any head speed. The solid golf ball of the present invention comprises a core containing at least one layer which is molded by vulcanizing the rubber composition including: (a) a base rubber, (b) a co-crosslinking agent, (c) an organic peroxide, and (d) a bromine-substituted thiophenol compound represented by the formula, or a monovalent or divalent metal salt thereof: (wherein at least one of R1 to R5 is Br).

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core, and at least one layer of a cover formed on the core, wherein at least one of the layers of the core is formed by vulcanizing and press-molding a rubber composition comprising (a) a base rubber comprising polybutadiene rubber containing a cis-1,4-bond of not less than 99%, (b) a co-crosslinking agent, and (c) an organic peroxide.

Abstract: A golf ball which improves adherence of a coating to a cover and which improves spin retention without sacrificing the other properties of the coating. The golf ball has a core, a cover of at least one layer covering the core and a coating formed on an outer surface of the cover, wherein a thickness of the coating is 25 to 125 &mgr;m, a 50%-modulus of the coating is 5 to 50 MPa, and a value R expressed by R=PL/CL/1000 is 0.01 to 0.5, where CL (mm) represents a thickness of an outermost layer of the cover and PL (&mgr;m) represents a thickness of the coating.

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core, and at least one layer of a cover, wherein at least one layer of the core is formed by vulcanizing a rubber composition comprising a base rubber, co-crosslinking agent, vulcanization initiator and filler, a calculated volume content of the co-crosslinking agent is within the range of 16.1 to 19.5% by volume, and a total calculated volume content of the base rubber and the co-crosslinking agent is within the range of 96.0 to 99.0% by volume, based on the total rubber composition, and an amount of the vulcanization initiator is within the range of 0.05 to 0.9 parts by weight, based on 100 parts by weight of the base rubber.

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core, and at least one layer of a cover formed on the core, wherein at least one layer including the inmost layer of the core is formed by vulcanizing a rubber composition comprising a base rubber, a co-crosslinking agent, a vulcanization initiator and a filler, the core has a center hardness in JIS-C hardness of 40 to 60, a surface hardness in JIS-C hardness of 80 to 95 and a hardness difference (B−A) between a hardness in JIS-C hardness at a distance of 5 mm from the center point of the core (B) and the center hardness (A) of not less than 1 to less than 10.

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core, and at least one layer of a cover formed on the core, wherein at least one of the layers of the core is formed by vulcanizing and press-molding a rubber composition comprising a base rubber, co-crosslinking agent, organic peroxide, filler and specific organic sulfur compound which contains substituent groups having a substituent constant of not less than 1.42.

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel.

Abstract: The present invention provides a solid golf ball which imparts a superior shot feeling to the golfer and exhibits stabilized repulsion performance when it is hit at any head speed.

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core, and at least one layer of a cover formed on the core, wherein at least one of the layers of the core is formed by vulcanizing and press-molding a rubber composition comprising a base rubber, co-crosslinking agent, organic peroxide, filler and specific organic sulfur compound which contains substituent groups having a substituent constant of not less than 1.42.

Abstract: The present invention provides a solid golf ball having exceptional rebound characteristics and flight performance, as well as good shot feel.

Abstract: The present invention provides a solid golf ball which gives a superior shot feeling to the golfer and exhibits stabilized repulsion performance when it is hit at any head speed.

Abstract: The present invention provides a solid golf ball having excellent rebound characteristics while maintaining good shot feel. The present invention relates to a solid golf ball comprising at least one layer of a core and at least one layer of a cover formed on the core, wherein at least one layer of the core is obtained by vulcanizing and molding a rubber composition, the rubber composition comprises (a) based on 100 parts by weight of a base rubber, (b) from 15 to 50 parts by weight of a metal salt of &agr;,&bgr;-unsaturated carboxylic acid having 3 to 8 carbon atoms as a co-crosslinking agent, and the metal salt of &agr;,&bgr;-unsaturated carboxylic acid has an average particle size of 6 to 30 &mgr;m, and (c) 0.1 to 1.0 parts by weight of a vulcanization initiator.

Abstract: A thread rubber for thread wound golf balls having a high impact resilience and high strength, wherein the thread rubber is obtained by vulcanizing a rubber composition which comprises (a) a rubber component selected from the group consisting of natural rubber, a synthetic high-cis-polyisoprene rubber and a mixture thereof, (b) at least one specific diaryl disulfide, (c) a vulcanizing agent, and (d) antioxidant; the compound (b) being present in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the rubber component (a).

Abstract: A phosphine compound represented by one of the formulas: ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, each represent a phenyl group or a phenyl group substituted with a halogen atom or a lower alkyl group or taken together form a divalent hydrocarbon group; and R.sup.3 and R.sup.4, which may be the same or different, each represent a lower alkyl group, a phenyl group or a phenyl group substituted with a halogen atom, a lower alkyl group or a lower alkoxy group or taken together form a divalent hydrocarbon group, and wherein R.sup.6 and R.sup.6' which may be the same or different, each represent a hydrogen atom, a lower alkyl group or a lower alkoxy group; R.sup.5, R.sup.5', R.sup.11 and R.sup.11' which may be the same or different, each represent a hydrogen atom, a lower alkyl group, a lower alkoxy group or a halogen atom; or a pair of R.sup.5 and R.sup.6 or a pair of R.sup.5' and R.sup.6' may form a ring; R.sup.7 and R.sup.