Bridgestone Corporation

Bridgestone Tire Company Limited

Japan Synthetic Rubber Co., Ltd.

Bridgestone Sports Co., Ltd.

Other

Toshiba Silicone Co., Ltd.

Seisuke Tomita

Tatsuo Fujimaki

Shinichi Kakiuchi

Yoshinori Egashira

Tomoharu Yamada

Hisashi Yamagishi

Noboru Oshima

Shinsuke Yamaguchi

Toshio Chikaraishi

Takatsugu Hashimoto

Yoshito Yoshimura

Isamu Shimizu

Kazuyuki Takahashi

Tasuku Saito

Shigeki Endo

Minoru Ishiharada

Yuichi Ishino

Hiroshi Kaneda

Toshiyuki Osaki

Takehiro Tsukamoto

Keisuke Ihara

Yutaka Masutani

Masaki Ogawa

Yasumasa Takeuchi

Mitsuhiko Sakakibara

Junichiro Watanabe

Fumio Tsutsumi

Takayuki Maruyama

Kazuo Sugiura

Yasushi Hirata

Yuichi Funahashi

Noboru Yamazaki

Akio Takashima

Shuichi Watanabe

Yoichi Watanabe

Hironori Matsumoto

Yoshiki Fukuyama

Takashi Hoshino

Setsuko Imaizumi

Michitaka Takeshita

Michio Okuyama

Keiko Katayama

Michio Itoh

Takeshi Kinoshita

Akihiro Maehara

Yoshimi Hasegawa

Hideaki Nomura

A golf ball is provided with a marking portion including a hologram implementing a color and/or pattern produced by optical interference. The marking portion is provided on the entire surface of the golf ball or only in dimples. The marking portion including a hologram reflects light and thereby glitters, and is visually recognized as a three-dimensional image, thereby improving visibility of the ball from a distance. The marking portion including a hologram allows an image to be readily reproduced by irradiating a laser beam thereto. Thus reproduced image facilitates an automated inspection for the appearance of the marking portion.

Golf ball

A multi-piece solid golf ball has a solid core of multi-layer configuration including an inner layer circumscribed by an outer layer. The core inner layer is formed from a rubber composition. The core outer layer is formed thereon by injection molding a mixture of 100-50 wt % of a polyether ester type thermoplastic elastomer having a Shore D hardness of 30-50 and a Tg of up to -25.degree. C. and 0-50 wt % of an ethylene-(meth)acrylate copolymer ionomer having a flexural modulus of 200-400 MPa. The core is surrounded by a cover of an ethylene-(meth)acrylate copolymer ionomer having a flexural modulus of 200-450 MPa and a Shore D hardness of 55-68. The ball shows improved flying performance, feel on impact and durability and lends itself to mass production.

Multi-piece solid golf ball

One-piece and multi-layered golf balls are improved in flying performance by forming the one-piece ball entirely or multi-layered golf ball core from a rubber composition comprising a base rubber, an unsaturated carboxylic acid metal salt, and an organic sulfur compound and/or a metal salt thereof.

Solid golf ball

Electroviscous fluid

One-piece and multi-layered golf balls are improved in flying performance by forming the one-piece ball entirely or multi-layered golf ball core from a rubber composition comprising a base rubber and a co-crosslinking agent in the form of a premix of an unsaturated fatty acid metal salt and a liquid polymer.

The electroviscous fluid is a suspension composed of a finely divided dielectric solid dispersed in an electrically nonconductive oil. The viscosity of the fluid increases swiftly and reversibly under an influence of electric field applied thereto and the fluid turns to a state of plastic or solid when the influence is sufficiently strong. The electroviscous fluid of the present invention comprises 1-60% by weight of a dispersed phase of carbonaceous particulates having average particle size of 0.01-100 micrometer, and 99-40% by weight of a continuous liquid phase of an electric insulating oil having a viscosity of 0.65-500 centistokes at room temperature. The electroviscous fluid exhibits an excellent electroviscous effect even at a high temperature with a low electric power consumption together with maintaining the improved electroviscous effect for a long period of time.

A golf ball with three dimples (14) having the same shape and an equal diameter and an equal depth are distributed about the center of each spherical regular triangle (13) such that three line segments connecting the centers of the three dimples (14) define a regular triangle (15). The length of each line segment, that is, length (D.sub.D1) of one side of the regular triangle (15) does not exceed twice the diameter (D.sub.m) of the dimples (14). No other dimples are located within the regular triangle (15) associated with the three dimples (14). Two dimples (16) having the same diameter as the three dimples (14) are distributed on each side of the spherical regular triangle (13) in symmetry with respect to its middle point such that the distance (D.sub.D2) between the centers of the two dimples (16) does not exceed twice the diameter (D.sub.m) of the dimples (16).

In a thread-wound golf ball comprising a thread-wound core and a cover, the cover is formed of a vulcanized rubber composition comprising a base rubber containing at least 30% by weight of transpolyisoprene and has a vulcanizing sulfur content ratio between radially outer and inner half regions of from 1/2 to 4/1. Sufficient vulcanizing sulfur available throughout the cover renders the cover to be resistant to cut and shear so that the ball becomes durable.

Thread-wound golf ball

A golf ball with improved flight distance is disclosed. The golf ball has at least three pluralities of dimples in its spherical surface. The dimples of each plurality share the same diameter and depth characteristics, such characteristics varying from the corresponding diameter and depth characteristics of the dimples of the other pluralities of dimples. However, the ratio of the diameter to depth of the dimples of a particular plurality of dimples approximates the ratio of the dimples in every other plurality of dimples such that the difference between the ratio of the dimple of one plurality of dimples and any other plurality of dimples is less than 0.3.

A thread-wound golf ball comprising; a liquid center having a diameter in the range of 26 to 30 mm and having a hollow spherical center backing with a liquid contained therein, a thread rubber layer, and a cover thereon, said center backing being formed of a rubber material selected from the group consisting of natural rubber and blends of natural rubber having a JIS A hardness of 44 to 58 and a thickness of 1.7 to 2.3 mm, said liquid having a specific gravity of 1.01 to 2.5, and said liquid center exhibiting a deflection of 10 mm under a load of 1 to 2 kg and a deflection of 15 mm under a load of 3 to 6.5 kg.

A golf ball having at least three different sizes of dimples and whose total dimple area quotient is optimized for increasing the golf ball's flying distance. The dimple area quotient represents the sum of the surface area indexes of all dimples divided by the surface area of the ball. The golf ball contains a plurality of dimples disposed about the spherical surface of the golf ball, and said plurality of dimples includes at least three types of dimples, said plurality of dimples having a total dimple surface area quotient Dst of at least 4, wherein the total dimple surface area quotient Dst is defined as: ##EQU1## wherein n is a positive integer of at least 3, k is one of plurality of discrete dimple groups covering the spherical surface of said golf ball,

A covering composition comprising an ionomer resin and a low-molecular weight polyethylene wax has improved impact resistance. A golf ball having a core enclosed in a cover thereof is fully durable and exhibits satisfactory flying performance.

A golf ball having at least three types of dimples arranged in a specific distribution pattern has improved aerodynamic symmetry and offers consistent flying performance. Three phantom orthogonal great circles are drawn on the spherical surface of the ball to define eight spherical regular triangles, and phantom perpendiculars are extended from the three apexes of each spherical regular triangle to the opposite sides to divide the spherical regular triangle into six equal spherical right triangles, thereby dividing the entire spherical ball surfaces into 48 equal spherical right triangles.

A pressure-sensitive sensor comprises an optical wave guide consisting of a core and a clad, and a light emitting means and a light receiving means each connected to the optical wave guide. The core is made from a transparent material having a refractive index somewhat larger than that of a material constituting the clad and selected from chloroprene rubber, urethane rubber, silicone rubber, fluorine rubber, acrylic rubber, ethylene-propylene rubber, ethylene-propylene-diene terpolymer rubber and epichlorohydrin rubber.

Method of producing a flexible optical wave guide

A pressure-sensitive sensor comprises an optical wave guide consisting of a core and a clad, and a light emitting means and a light receiving means each connected to the optical wave guide. The core is made from a transparent material having a refractive index somewhat larger than that of a material constituting the clad and selected from chloroprene rubber, urethane rubber silicone rubber, fluorine rubber, acrylic rubber, ethylene-propylene rubber, ethylene-propylene-diene terpolymer rubber and epichlorohydrin rubber.

Pressure-sensitive sensors

Growing community of inventors

Tokorozawa, Japan

Seisuke Tomita