Bridgestone Sports Co., Ltd.

Dow Corning Toray Company, Ltd.

Yoshihiro Yamana

Hidekazu Saito

Hiroyuki Nagasawa

Hiroki Kimura

Yoshinori Egashira

Junji Umezawa

Yuichi Tsuji

Kazufumi Tabata

Takayoshi Otomo

Katsumi Kihara

Kazumasa Hattori

The present invention provides a polyurethane which is non-sticky, exhibits superior handling properties and superior moldability, and has superior adhesive properties with silicones even if a surface activation treatment is not carried out beforehand. The polyurethane of the present invention contains polyol units and organic polyisocyanate units. The polyol units contain an alkenyl group-containing organopolysiloxane structure in an amount ranging from 0.01 to 20% by weight with respect to the weight of the aforementioned polyurethane.

Polyurethane and manufacturing method therefor, master batch, ink binder, ink composition, thermoplastic polymer composition for molding, molded body, and composite molded body and manufacturing method therefor

A method of manufacturing golf balls composed of a core and a cover of one or more layer that encloses the core, at least one cover layer being made of a thermoplastic polyurethane composition characterized by including at least 90 wt % of a thermoplastic polyurethane obtained by a polyurethane-forming reaction of an organic diisocyanate compound with a long-chain polyol and a chain extender, which thermoplastic polyurethane composition cover layer has an inherent viscosity in a DMF solvent of larger than 1.5 dl/g and an inherent viscosity in a 0.05 mol/L n-butylamine-containing DMF solution of larger than 0.5 dl/g, the golf ball manufacturing method being characterized by:

Method for producing golf ball

A method of manufacturing golf balls composed of a core and a cover of one or more layer that encloses the core, at least one cover layer being made of a thermoplastic polyurethane composition characterized by including at least 90 wt % of a thermoplastic polyurethane obtained by a polyurethane-forming reaction of an organic diisocyanate compound with a long-chain polyol and a chain extender, which thermoplastic polyurethane composition cover layer has an inherent viscosity in a DMF solvent of larger than 1.5 dl/g and an inherent viscosity in a 0.05 mol/L n-butylamine-containing DMF solution of larger than 0.5 dl/g, the golf ball manufacturing method being characterized by: conditioning the thermoplastic polyurethane to a pre-processing moisture content of 500 ppm or less, then injection molding the moisture-conditioned thermoplastic polyurethane to form the thermoplastic polyurethane composition cover layer. Golf balls produced by this method have a high rebound and excellent spin characteristics and scuff resistance, are recyclable in a molding operation, and have excellent manufacturability.

A golf ball composed of a core and one or more cover layer which encloses the core is characterized in that at least one cover layer is made of a thermoplastic polyurethane composition characterized by including at least 90 wt % of a thermoplastic polyurethane obtained by a polyurethane-forming reaction of an organic diisocyanate compound with a long-chain polyol and a chain extender, and in that the polyurethane composition cover layer is characterized that an inherent viscosity in a DMF solvent is larger than 1.5 dl/g and an inherent viscosity in a DMF solution containing 0.05 mol/L n-butylamine is larger than 0.5 dl/g. The golf ball has a high rebound, an excellent scuff resistance, is recyclable in a molding operation, and has excellent manufacturability.

Golf ball

In a golf ball composed of a core and one or more cover layers which enclose the core, at least one cover layer is made primarily of a thermoplastic polyurethane obtained by a polyurethane forming reaction of an organic polyisocyanate compound with a long-chain polyol and a chain extender, and satisfies conditions (1) to (3) below: The golf ball has an improved scuff resistance, particularly an improved low-temperature scuff resistance.

A three-piece solid golf ball composed of a solid core, an intermediate layer which encloses the core, and a cover layer which encloses and is softer than the intermediate layer is characterized in that the solid core undergoes a deflection of 2.8 to 3.6 mm when a load of 130 kg is applied thereto from an initial load of 10 kg and has a surface hardness and a center hardness which differ by at least 15 Shore D hardness units; the intermediate layer has a surface hardness which differs from the surface hardness of the solid core by not more than 12 Shore D hardness units; and the cover layer has a surface hardness which differs from the surface hardness of the intermediate layer by at least 7 Shore D hardness units, is made primarily of a thermoplastic polyurethane, and has a thickness in a range of 0.5 to 1.3 mm. This combination of features provides an overall outstanding golf ball endowed with excellent flight characteristics, excellent controllability and durability, and a soft feel on impact.

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Tokyo, Japan

Yoshihiro Yamana