Yoshikazu Yabuki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
Abstract: The present invention provides a golf ball which is superior in hit feeling, control properties, flying performances and cut resistance. As the base resin of the cover of the golf ball, a heated mixture composed of (A) an ionomer resin or a mixture thereof, (B) a terpolymer resin of .alpha.-olefin, unsaturated carboxylate and unsaturated carboxylic acid and (C) a glycidyl group-containing .alpha.-olefinic copolymer resin is used.
Abstract: A golf ball has a surface uniformly covered with a paint coat so that carrying properties of dimples can be stably elicited. A paint to which is applied a voltage of more than 50,000 V is supplied to a disk revolving at a speed of more than 15,000 rpm for atomization, the atomized paint being coated on the surface of the golf ball to form a paint coat within a thickness range of 5 to 60 .mu.m, with a maximum/minimum coat thickness ratio of 1 to 2.
Abstract: A thread wound golf ball comprising a solid center, a thread rubber layer provided on the outside of the solid center and a cover for covering the thread rubber layer, wherein said center has a strain of 0.5 to 5 mm when 500 g weight is loaded on the solid center and is composed of an inner rubber portion, and said inner rubber portion has a crosslinked rubber structure, formed from a composition comprising 100 parts by weight of a base rubber and 30 to 500 parts by weight of an oily substance, whereby bleeding of the oily substance is prevented, wherein said oily substance is selected from the group consisting of petroleum compounded oil, plasticizer, rubber substitute, alkylbenzene, liquid rubber and a mixture thereof; and wherein said oil-resistant substance is selected from the group consisting of ionomer resin, acrylonitrile-butadiene rubber, chloroprene rubber, urethane rubber, fluorosilicone rubber and a mixture thereof.
Abstract: The objective of the present invention is to bring hit feeling of two-piece balls closer to that of thread-wound golf balls. The two-piece golf ball of the present invention comprises a core formed from a rubber composition comprising a base rubber, a co-crosslinking agent and an organic peroxide, and a cover covering the core, wherein said core has the following hardness distribution when measured by a JIS-C hardness meter;(1) hardness at a center: 58-73(2) hardness at 5-10 mm from the center: 68-78(3) hardness at 15 mm from the center: 76-88(4) surface hardness: 78-88(in the hardness distribution, hardness (2) is substantially constant being within the above range, of which tolerance is within .+-.3 and the other values satisfy the relation of (1)<(2)<(3).ltoreq.(4) ), a compression deformation of the core is 2.8-3.5 mm when pressurized by an initial load of 10 kg up to a final load of 130 kg and said cover has a thickness of 1.5-1.9 mm.
Abstract: Disclosed is a method for coating a golf ball, wherein the coating efficiency of the paint is high and a uniform coating can be formed. According to the method, the paint is sprayed on a golf ball moving with rotation on the circumference of a circle having a diameter of 0.5 to 1.5 m from a disc charged with 60,000 to 130,000 V, which is rotating at 20,000 to 40,000 rpm and is inclined or moving in the vertical direction, or a paint is sprayed in a direction at an angle of 45.degree. or less to the horizontal direction from a disc charged with the above voltage, which is rotating at the above number of revolutions, to coat the golf ball so that a ratio of the maximum film thickness to the minimum film thickness may be 1.5 or less after one round of coating.
Abstract: The present invention provides a solid golf ball having excellent flying performances, stability upon iron shot and good hit feeling.A solid core 1 comprising an center 1a and an outer shell 1b is coated with a cover 2 to give a three-piece solid golf ball. The center 1a has a diameter of 30.7 to 39.5 mm, a stiffness of 300 to 2,500 kgf/cm.sup.2 and a shore D hardness of 30 to 55. The outer layer core 1b has a thickness of 1.0 to 4.0 mm, a stiffness of 2,500 to 6,000 kgf/cm.sup.2 and a shore D hardness of 55 to 75. The composition of both cores is a butadiene rubber. The cover 2 has a thickness of 0.6 to 2.0 mm, a stiffness of 1,000 to 2,500 kgf/cm.sup.2 and a shore D hardness of 40 to 55. The composition of the cover is an ionomer resin or a mixture of the ionomer resin and a flexible resin.
Abstract: A three-piece solid golf ball comprising an inner core 1a, an outer core 1b, and a cover formed principally of an ionomer resin, wherein said inner core 1a has a diameter of 10 to 38 mm, said outer core 1b has a specific gravity of 0.2 to 0.79 and has a diameter of 37 to 40 mm and a total weight of the inner core 1a and the outer core 1b is within the range of 32.0 to 39.0 g.
Abstract: A two-piece golf having a feel of hitting close to that of a thread-wrapped golf ball. A two-piece golf ball consisting of a core formed of a rubber composition containing a base rubber, a co-crosslinking agent, and an organic peroxide, and a cover covering the core, characterized in that:the core has the following hardness distribution according to JIS - C type hardness meter readings:(1) hardness at center, position A: 58-73(2) hardness at 5 to 10 mm from center, position B: 65-75(3) hardness at 15 mm from center, position C: 74-82(4) surface hardness, position D: 76-84(wherein hardness (2) is generally constant within the range shown, with a variation range of .+-.3, and satisfies the relation (1)<(2)<(3).ltoreq.(4) in other respects), andthe core has a compression deflection of 3.5 to 4.3 mm when a load range of initial 10 kg to final 130 kg is applied, the cover having a thickness of 2.1 to 2.8 mm.
Abstract: The present invention provides a two piece golf ball having excellent hit feeling, which comprises a core and a cover, wherein the core has a deformation (compression deformation) of 3.7 to 4.5 mm caused by applying from 10 kg of an initial load to 130 kg of a final load, and is prepared from a rubber composition comprising 100 parts by weight of a cis-1,4-polybutadiene rubber and 20 to 30% by weight of a metal salt of an unsaturated carboxylic acid, and wherein the cover has a stiffness modulus of 3,700 to 4,500 kg/cm.sup.2 and a thickness of 2.2 to 2.9 mm.
Abstract: A golf ball has one great circle and four one-half great circles which all intersect no dimples. Eight end points which include two end points of each one-half great circle are formed at the one great circle. These end points do not coincide with each other on the great circle. One of the one-half great circles intersects the other one-half great circle at a right angle at the middle point thereof on each of the great circle. In other words, an upper semispherical mold for an octahedral dimple golf ball arrangement is rotated a certain angle relative to the lower mold such that two of the three great circles are divided into four one-half great circles. The parting line of the mold becomes the one remaining great circle. In this manner, a more uniform flight of the golf ball canbe obtained regardless of whether the ball is hit on a seam, semi-seam of non-seam area.
Abstract: A golf ball which comprises a spherical surface having a parting line at its equator and having a plurality of dimples formed thereon,wherein the dimples are formed so that the ratio, y, of the sum total of the flat surface area of the dimples to the surface area of the same sphere having no dimples formed thereon is within the range((0.046) (X).sup.1/2 -0.172)+0.04.gtoreq.Y.gtoreq.((0.046)(X).sup.1/2 -0.172)-0.04wherein X represents the total number of dimples;and wherein a dimple lying within a region S, which extends from 30.degree. below the parting line to 30.degree. above the parting line, has a value VS, and a dimple of the same diameter only lying within the region P, which comprises the surface of the sphere that is not within region S, has a volume VP, such that the ratio of the volumes of dimples having the same diameters but in different regions is within the range of;1.02.ltoreq.VS/VP <1.10, when y<0.70,1.10.ltoreq.VS/VP, <1.18, when 0.70.ltoreq.y<0.80, and1.18.ltoreq.VS/VP, when 0.
Abstract: A golf ball having a spherical surface with a great circle zone along a parting line, the surface being divided by a central angle .theta. of the sphere of 10.degree..ltoreq..theta.<60 above and below the parting line to form a central S region and a polar P region. A plurality of kinds of dimples are arranged in both the S region, SD.sub.n, and the P region, PD.sub.n, the dimples of each region being geometrically symmetric about the parting line. The curvatures diameters, depths and volumes of the dimples within a region differ between kinds of dimples. At least one type of dimple in the S region has a corresponding type of dimple in the P region, the correspondence being equal curvature. The value of the volumes of the corresponding pairs of dimples are set such that 1.0223 VSD.sub.n /VPD.sub.n .ltoreq.1.25.