Abstract: Golf ball 2 has spherical core 4, cover 6 positioned outside the core 4, mark layer 8 and paint layer 10. The resin composition of the cover 6 includes composite particles. The composite particle has a nucleus and a coat layer. The nucleus is constituted with aluminum oxide. The coat layer is constituted with titanium oxide. The composite particles are flaky. The amount of the composite particles is 0.1 parts by weight or more and 15 parts by weight or less per 100 parts by weight of the base resin of the cover 6. The composite particles may be also dispersed in the paint layer 10. The amount of the composite particles in the paint layer 10 is 1 part by weight or more and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 10.

Abstract: A muscle-back iron golf club head includes a blade-like upper mass, a muscle-like lower mass, a planar front surface, a top surface, a sole surface, a heel surface, a toe surface, and a rear surface having a first contour. A recess is in the rear surface, the recess having a first portion in the blade-like upper mass and a second portion in the muscle-like lower mass. An insert may be provided in the recess, and such insert may substantially fill the recess and may include a back surface having a second contour which is different from the first contour of the club head rear surface.

Abstract: A golf club head is manufactured so as to be at least partially composed of martensitic stainless steel and to have an exterior surface. At least one chromium layer is deposited on at least a portion of the exterior surface of the golf club head. At least one outer layer is deposited by physical vapor deposition on at least a portion of the at least one chromium layer, the outer layer including a metal and a nonmetal.

Abstract: A golf club head having a club face for hitting a ball comprises a hollow main body provided with a front opening, and a face member disposed at the front of the main body so that a front surface thereof forms at least a major part of the club face, and a rear surface thereof faces a hollow of the main body. The peripheral edge of the face member is welded to the main body so as to form a weld bead, and the width of the weld bead is changed so that a difference (Wmax?Wmin) between the maximum width Wmax and minimum width Wmin is not less than 1 mm.

Abstract: A shaft 6 has layers. The layers include a straight layer in which an absolute angle ?a of a fiber to a shaft axis line is 10 degrees or less, a bias layer in which the angle ?a is 30 degrees or greater and 60 degrees or less, and a hoop layer in which the angle ?a is 80 degrees or greater. The layers include full length layers and a partial layer. The full length layers include full length bias layers and full length straight layers. The full length bias layers are located on the innermost side among the full length layers. The full length layer brought into contact with a low RC full length layer outside the full length bias layers is a high RC layer. The full length layer brought into contact with an outer surface of the full length bias layers is a high RC layer.

Abstract: Golf ball 2 has spherical main body 4, mark layer 6 and paint layer 8. The main body 4 has spherical core 10, and cover 12 provided to cover this core 10. The cover 12 does not include titanium oxide. The cover 12 includes a fluorescent colorant. The main body 4 has a chroma saturation of equal to or greater than 25. The paint layer 8 is constituted with a resin composition. This resin composition includes composite particles. The composite particle has a nucleus, and a coat layer provided to coat this nucleus. The nucleus is constituted with mica, while the coat layer is constituted with titanium oxide. The amount of the composite particles is 2 parts by weight or greater and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 8.

Abstract: A golf club head according to one or more aspects of the present invention may include a body comprising a front surface, having an opening therein for receiving a primary insert. One or more secondary inserts may be disposed in the primary insert and may include a leading surface and a trailing surface. The trailing surface may be physically exposed to the elements and the leading surface may be physically exposed and/or visually exposed.

Abstract: A method of evaluating a golf club is disclosed. The method includes a step (St1) of determining motions of the golf club during a swinging motion of a golf player including a period ranging from a time (Ts) to a time (Tf); a step (St2) of obtaining in a time series power index values (Pw) during the period ranging from the time (Ts) to the time (Tf), based on the result of the determination; a step (St3) of obtaining a power integration value (Sp) by integrating the power index values (Pw) during the period ranging from the time (Ts) to the time (Tf); a step (St4) of calculating club energy (Eg) of the golf club at the time (Tf); and a step (St5) of quantitatively evaluating club suitability based on the power integration value (Sp) and the club energy (Eg). Each of the power index values (Pw) is a value which is correlated to a power of a work provided from the golf player to the golf club.

Abstract: An object of the present invention is to improve the abrasion-resistance of a golf ball having a polyurethane cover. Another object of the present invention is to enhance the resilience and the shot feeling thereof. The present invention provides a golf ball having a cover, said cover comprising, as a base resin, a thermoplastic polyurethane containing a polycarbonate polyol as a constitutional component, wherein the polycarbonate polyol has, as a repeating constitutional unit, a repeating unit (A) shown in a following Formula (I), and a repeating unit (B) shown in a following Formula (II) and having a different structure from that of (A), and a molar ratio of (A)/(B) is from 30/70 to 70/30. In Formula (I), R1 is a bivalent residue obtained by removing two hydroxyl groups from a diol having 4 to 6 carbon atoms. In Formula (II), R2 is a bivalent residue obtained by removing two hydroxyl groups from a diol having 4 to 6 carbon atoms.

Abstract: A hollow golf club head includes a sole, a crown, a skirt, and a striking face. The golf club includes a junction interconnecting the sole, crown, and skirt to the striking face, the junction including at least one stiffening member.

Abstract: In this manufacturing method, a tubular body 18 having a rib 16 provided therein is obtained. The manufacturing method includes the steps of: preparing a mandrel 2 divided into two or more divided bodies d1 along a longitudinal direction of the mandrel 2; winding a prepreg r1 for a rib around at least one of the divided bodies d1; combining all the divided bodies d1 to obtain a first intermediate body 10 after the step of winding the prepreg r1 for the rib; winding a prepreg g1 for the outer peripheral part around an outside of the first intermediate body 10 to obtain a second intermediate body; heating the second intermediate body to obtain a cured laminate; and extracting the mandrel 2 from the cured laminate. Preferably, the mandrel is equally divided in a circumferential direction. Preferably, a winding start end part t2 of the prepreg r1 for the rib and a winding finish end part t1 thereof overlap with each other.

Abstract: A golf club head according to one or more aspects of the present invention may include a strike face, a rear wall behind the strike face, and a perimeter-weighting element at least partially surrounding the rear wall. The club head may further include a preload spacer associated with the rear wall and a resilient component associated with the perimeter-weighting element. The preload spacer engages the resilient component to provide positive reinforcement of the coupling between the resilient component and the perimeter-weighting element.

Abstract: An object of the present invention is to provide a golf ball excellent in fluidity, adhesion of the paint film, and repulsion. Another object of the present invention is to provide a golf ball which is excellent in durability and low-temperature durability.

Abstract: A head 2 has a face line 8 having a depth of D1 (mm). In a section line of a surface of the face line 8, a boundary between a land area LA and the face line 8 is defined as a point Pa; a point of which a depth is [D¼] (mm) is defined as a point Pb; a point of which a depth is [D½] (mm) is defined as a point Pc; a point of which a depth is [(D1)×(¾)] (mm) is defined as a point Pd; a radius of a circle CL1 passing through three points of the point Pa, the point Pb, and the point Pc is defined as R3 (mm); a straight line passing through the point Pc and the point Pd is defined as a straight line Lcd; a straight line perpendicular to the land area LA is defined as a straight line Lp; and an angle between the straight line Lcd and the straight line Lp is defined as ?m. At that time, the radius R3 is 0.01 (mm) or greater and 0.10 (mm) or less, and the angle ?m is 40 degrees or greater and 70 degrees or less.

Abstract: A hollow golf club head having face end and tail ends, a strike face at the face end, a crown, a sole of length >3.5 inches, volume 0.300 cm3, and a structural response modifying constraining member having first and second ends, the second being forward of the first and spaced from the strike face, the contraining member extending vertically and in contact with the sole and the crown at its first and second ends, and extending horizontally a maximum distance that is <40% of the sole length, when the club head is in address position.

Abstract: A golf club head according to one or more aspects of the present invention may include a main cavity having at least one auxiliary cavity and a base surface. An insert may be associated with the base surface and may comprise at least two contact elements, with a bridge member disposed therebetween. Different contact elements of the insert may be disposed in separate respective auxiliary cavities, such that each contact element may be associated with the base surface. The bridge member of the insert may be dissociated from the base surface. Moreover, a surface coating may be selectively applied to the head to permit a durable adhesive bond between the insert and the base surface.

Abstract: A hollow golf club head is disclosed, wherein a front member including a face portion and a hosel portion of the club head is made of a material having a specific gravity ?1; a rear member forming a backmost point of the club head is made of a material having a specific gravity ?2; and an intermediate member extending annularly through in a crown portion, a sole portion and a sidewall portion of the head is made of a material having a specific gravity ?3; and the specific gravity ?3 is more than the specific gravity ?1 which is more than the specific gravity ?2.

Abstract: A golf club may include a front surface, a rear surface having a recess, and an insert at least partially disposed in the recess. The insert may comprise a durometer hardness of less than about 95 Shore A and a cavity having a reinforcement member disposed therein. Preferably, the durometer hardness of the reinforcement member is also less than about 95 Shore A. The insert may further comprise an anterior perimetric boundary having a first length and a posterior perimetric boundary having a second length. The ratio of the first length to the second length may be less than 1 and greater than 0.5. In one example, the insert may have a triangular front profile and a triangular side profile.

Abstract: An object of the present invention is to provide a golf ball excellent in fluidity, adhesion of the paint film, and repulsion. Another object of the present invention is to provide a golf ball which is excellent in durability and low-temperature durability. The present invention provides a golf ball comprising: a core and a cover covering the core, wherein the cover is formed from a cover composition that contains as a resin component, (A) a specific high melt viscosity ionomer resin being neutralized with at least two metal ions, and (B) a low melt viscosity ionomer resin being neutralized with at least two metal ions, in a ratio of (A) the high melt viscosity ionomer resin/(B) the low melt viscosity ionomer resin being 55 mass % to 99 mass %/45 mass % to 1 mass %.

Abstract: The present invention provides a solid golf ball that exhibits a high resilience performance and a high flight performance and gives a good shot feeling. The present invention relates to a solid golf ball including: a core including at least one layer; and a cover including at least one layer, the cover being provided to cover the core, wherein the at least one layer of the core is prepared by vulcanization-molding a rubber composition including: (a) a base rubber; (b) a co-crosslinking agent; (c) an organic peroxide; (d) a filler; and (e) a disulfide compound represented by formula (I): R1—S—S—R2??(I) wherein R1 and R2 each represent any one of the following groups: an aromatic hydrocarbon group; an aliphatic hydrocarbon group having two or more carbon atoms; a heterocyclic hydrocarbon group; and an alicyclic hydrocarbon group, each of which is optionally substituted, and R1 is a group different from R2.