Sumitomo Rubber Industries Limited

Sri Sports Limited

Kazunari Yoshida

Keiji Moriyama

Keiji Ohama

Satoshi Iwami

Takahiro Sajima

Yoshinori Sano

Mikio Yamada

Tetsuo Yamaguchi

Takeshi Asakura

Hidenori Hiraoka

Takashi Teraguchi

Takumi Nishino

Shinji Ohshima

The invention provides a multi-piece solid golf ball having soft, good shot feel, excellent flight performance, high rebound characteristics and high launch angle, when hit by golfers who swing a golf club at high or low head speed using all golf clubs, namely, a driver to an iron club, a putter. The multi-piece solid golf ball has a core having an inner core and an outer core covering the inner core, and at least one layer covering the core; the inner core has a diameter of 30 to 40.4 mm and surface hardness of 60 to 85 JIS-C, and center JIS-C hardness of the inner core lower than the surface hardness by 5 to 30; the outer core has a thickness of 0.2 to 1.3 mm, and a surface JIS-C hardness of the outer core lower than the surface hardness of the inner core by 2 to 30.

Multi-piece solid golf ball

The present invention provides a three-piece solid golf ball having long flight distance, by accomplishing high launch angle and low spin amount immediately after hitting, while maintaining soft and good shot feel when hitting at low head speed. The present invention relates to a three-piece solid golf ball comprising a center, an intermediate layer formed on the center, and an outer layer covering the intermediate layer, wherein the center has a central point hardness in JIS-C hardness of 55 to 75 and a surface hardness in JIS-C hardness of 65 to 85, the surface hardness is higher than the central point hardness by 10 to 20, a JIS-C hardness of the intermediate layer is higher than the surface hardness of the center by 10 to 20, and a JIS-C hardness of the outer layer is higher than the hardness of the intermediate layer by 5 to 15.

Three-piece solid golf ball

The present invention provides a multi-piece solid golf ball comprising a core consisting of an inner core and an outer core, and one or more layers of cover, wherein the inner core has a diameter of 30 to 39.5 mm and a center hardness in JIS-C hardness of 55 to 70, and is formed from press molded rubber composition comprising polybutadiene, a co-crosslinking agent, an organic peroxide and a filler, and the JIS-C hardness at a distance of 15 mm from the center point of the inner core is higher than the center hardness by 5 to 20; the outer core has a thickness of 0.3 to 2.0 mm and a surface hardness in JIS-C hardness of 75 to 90, and is formed from press molded rubber composition, and the surface hardness of the outer core is higher than the center hardness of the outer core is higher than the center hardness of the inner core by 10 to 35; and the cover contains thermoplastic resin as a base resin, and the outmost cover layer has a thickness of 1.5 to 2.5 mm and a surface hardness in Shore D hardness of 64 to 72.

Multi-piece solid golf ball and method of making the same

The present invention provides a four-piece solid golf ball having excellent flight performance and good shot feel at the time of hitting. The present invention relates to a four-piece solid golf ball comprising a core, an intermediate layer formed on the core, an outer layer formed on the intermediate layer and a cover covering the outer layer, wherein the core has a surface hardness in JIS-C hardness of 67 to 85, a JIS-C hardness of the intermediate layer is higher than the surface hardness of the core, and a JIS-C hardness of the outer layer is higher than the hardness of the intermediate layer.

Four-piece solid golf ball

The invention provides a multi-piece solid golf ball having improved flight performance, controllability and good shot feel at the time of hitting. The multi-piece solid gold ball has a core having at least one layer, an intermediate layer formed on the core, and a cover covering the intermediate layer. When thickness of the intermediate layer is represented as X (mm) and JIS-C hardness of the intermediate layer is represented as Y, then X is 0.3 to 1.5 mm, X and Y have a correlation represented 10X&plus;55&lE;Y&lE;10X&plus;75, and the JIS-C hardness of the cover is 70 to 93.

The present invention provides a multi-piece solid golf ball having very soft and good shot feel at the time of hitting, and having high rebound characteristics and excellent flight performance, while maintaining good productivity and the like. The present invention relates to a multi-piece solid golf ball comprising a core consisting of a center and at least one layer of intermediate layer formed on the center, and a cover covering the core, wherein the intermediate layer comprises at least one layer formed from a rubber composition comprising 20 to 60 parts by weight of &agr;,&bgr;-unsaturated carboxylic acid or metal salt thereof and 5 to 70 parts by weight of &agr;,&bgr;-unsaturated carboxylic acid ester, based on 100 parts by weight of a base rubber.

A golf ball retaining high coefficient of restitution inherent and having fine shot feeling with clubs such as drivers, irons and putters is disclosed. A multi-piece golf ball comprising; a center core having a JIS-C hardness of not more than 75, a cover having a JIS-C hardness of not less than 85, a core enclosing layer which directly enclose said center core having a JIS C hardness smaller than the others, and a r.d.preventing layer which prevents a restitution coefficient degradation being internally disposed in contact with said cover and having a JIS C hardness greater than the others.

Multi-piece golf ball

A Golf ball retaining high coefficient of restitution inherent in solid golf balls and having excellent shot feeling is disclosed. A multi-piece golf ball comprising: an inner core which is positioned in a central part of the golf ball, and has a JIS-C hardness of 75 or smaller; an outer core which encloses the inner core; an outer cover which is positioned in a surface part of the golf ball; and an inner cover which is placed on the inside of the outer cover, and has a JIS-C hardness of 80 or larger, wherein a JIS-C hardness of the outer core is smaller than that of the other components, and a JIS-C hardness of the outer cover is larger than that of the other components.

The present invention is directed to a multi-piece solid golf ball exhibiting excellent flight performance by optimizing the trajectory of the golf ball during flight. The golf ball of the present invention satisfies the formula 1020&lE;(NY&plus;266H)&lE;1085 with total number of dimples being N, the quotient Y being determined by dividing A by B in which A is the total area of a plane defined by a dimple edge and B is a surface area of a sphere when the sphere is formed assuming that there is no dimple on the cover, and a deformation amount H when applying from an initial load of 10 kgf to a final load of 130 kgf on the golf ball.

Solid golf ball having defined hardness profile

Hollow solid golf ball

A golf ball includes a core and a cover which covers the core, wherein a ratio between the primary natural frequency (CF.sub.1) of the core and the primary natural frequency (BF.sub.1) of the golf ball satisfies a following mathematical relation:

Method of making a golf ball with improved flight distance and shot

A three piece solid golf ball with enhanced flight performance and without diminished shot feel at a time of hitting, which includes a core, an intermediate layer formed on the core and a cover covering the intermediate layer. The golf ball, when hit at a head speed of 40 m/sec by a driver equipped with a swing robot, has a maximum impact force of 1,100 to 1,250 kgf and when hit at a head speed of 2.9 m/sec by a putter, has a maximum impact force of 40 to 50 kgf.

Growing community of inventors

Kasai, Japan

Kazunari Yoshida