Golf ball polyurethane composition and golf ball
AssigneeDunlop Sports Co. Ltd.
InventorsKazuyoshi Shiga, Ryo Murakami, Toshiyuki Tarao, Takahiro Shigemitsu
Life of this patent
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Abstract
An object of the present invention is to provide a golf ball polyurethane composition excellent in resilience. Another object of the present invention is to provide a golf ball excellent in a shot feeling and resilience. The present invention provides a golf ball polyurethane composition comprising, as a resin component, a polyurethane elastomer including a polyisocyanate with at least two alicyclic hydrocarbon structures having 3 or more carbon atoms as a constituting component, and having a spin-lattice relaxation time (T1) of 13C nucleus of 7.3 seconds or less measured by a High resolution solid state nuclear magnetic resonance (NMR) method.
Claims10
A golf ball comprising a core composed of at least one layer and a cover covering the core, wherein
- at least one layer of the core is formed from a golf ball polyurethane composition comprising, as a resin component, a polyurethane elastomer formed from a polyisocyanate component of 4,4′-dicyclohexylmethane diisocyanate, a polyol component of a polytetramethylene ether glycol having a number average molecular weight ranging from 2,000 to 3,000, and a chain extender component of 1,4-butanediol,
- the 4,4′-dicyclohexylmethane diisocyanate is in the form of its trans,trans-isomer in an amount of 50 mole % or more,
- the polyurethane composition has a spin-lattice relaxation time (T1) of 13C nucleus measured by a high resolution solid state carbon nuclear magnetic resonance (NMR) method of 7.3 seconds or shorter,
- the polyurethane composition has a slab hardness of 53 or less in Shore D hardness and rebound resilience of 60% or more, and
- the polyurethane elastomer is produced by reacting the 4,4′-dicyclohexylmethane diisocyanate with the polytetramethylene ether glycol in a molar ratio (NCO/OH) of an isocyanate group (NCO) of the 4,4′-dicyclohexylmethane diisocyanate to a hydroxyl group (OH) of the polytetramethylene ether glycol ranging from 1 to 1.5 to obtain an isocyanate group terminated urethane prepolymer, and reacting the isocyanate group terminated urethane prepolymer with 1,4-butanediol in a molar ratio (NCO/OH) of an isocyanate group (NCO) of the isocyanate group terminated urethane prepolymer to a hydroxyl group (OH) of the 1,4-butanediol ranging from 0.9 to 1.1.
A golf ball comprising a one-piece golf ball body formed from a golf ball polyurethane composition which comprises, as a resin component, a polyurethane elastomer formed from a polyisocyanate component of 4,4′-dicyclohexylmethane diisocyanate, a polyol component of polytetramethylene ether glycol having a number average molecular weight ranging from 2,000 to 3,000, and a chain extender component of 1,4-butanediol, wherein
- the 4,4′-dicyclohexylmethane diisocyanate is in the form of its trans,trans-isomer in an amount of 50 mole % or more,
- the polyurethane composition has a spin-lattice relaxation time (T1) of 13C nucleus measured by a high resolution solid state nuclear magnetic resonance (NMR) method of 7.3 seconds or less,
- the polyurethane composition has a slab hardness of 53 or less in Shore D hardness and rebound resilience of 60% or more, and
- the polyurethane elastomer is produced by reacting the 4,4′-dicyclohexylmethane diisocyanate with the polytetramethylene ether glycol in a molar ratio (NCO/OH) of an isocyanate group (NCO) of the 4,4′-dicyclohexylmethane diisocyanate to a hydroxyl group (OH) of the polytetramethylene ether glycol ranging from 1 to 1.5 to obtain an isocyanate group terminated urethane prepolymer, and reacting the isocyanate group terminated urethane prepolymer with 1,4-butanediol in a molar ratio (NCO/OH) of an isocyanate group (NCO) of the isocyanate group terminated urethane prepolymer to a hydroxyl group (OH) of the 1,4-butanediol ranging from 0.9 to 1.1.
Dependencies are inferred from the claim text.