Abstract: Golf ball 2 has a spherical core 4, a mid layer 6 covering this core 4, a reinforcing layer 8 covering this mid layer 6, and a cover 10 covering this reinforcing layer 8. Base polymer of the mid layer 6 includes an ionomer resin as a principal component. The mid layer 6 has a hardness Hm as measured with a Shore D type hardness scale of equal to or greater than 55. Base polymer of the reinforcing layer 8 is a thermosetting resin. Base polymer of the cover 10 includes a thermoplastic polyurethane elastomer as a principal component. The cover 10 has a thickness Tc of equal to or less than 0.6 mm. The cover has a hardness Hc as measured with a Shore D type hardness scale of equal to or less than 54. Ratio (Tr/Tc) of the thickness Tr of the reinforcing layer to the thickness Tc of the cover is 0.005 or greater and 3.0 or less.

Abstract: An object of the present is to provide a golf ball having an increased spin rate on approach shots. Another object of the present invention is to provide a golf ball having a goof shot feeling on approach shots. The present invention provides a golf ball comprising a golf ball body and a paint film formed on a surface of the golf ball body, and having a coefficient of friction calculated using a contact force tester of 0.35 or more and 0.60 or less.

Abstract: An object of the present invention is to provide a golf ball having an excellent properties like flight distance and low temperature durability. The present invention provides a golf ball comprising: a core consisting of a center and one or more intermediate layers covering the center; and a cover covering the core, wherein at least one piece or one layer of said intermediate layers is formed from a highly elastic intermediate layer composition that contains (A) a highly elastic polyamide resin having a flexural modulus in a range from 700 MPa to 5,000 MPa; (B) a metal-neutralized product of ethylene-(meth)acrylic acid copolymer and (C) a resin having a polar functional group in a specific way.

Abstract: A golf ball 2 has a large number of dimples 10 on a surface thereof. The golf ball 2 meets the following mathematical formula (I): Y?3.8*X?2.894 ??(I), where X represents a ratio of a sum of areas of all the dimples 10 to a surface area of a phantom sphere of the golf ball, and Y represents a standard deviation (mm) of diameters of all the dimples 10.

Abstract: A measuring apparatus 10 for a golf club 34 includes: a club camera 20 capable of photographing the golf club; a control part 30 capable of controlling a timing at which the golf club is photographed; and three sensors capable of detecting passage of the golf club 34. The three sensors are defined as a first sensor S1, a second sensor S2, and a third sensor S3 in this order from a point close to a position of a golf ball. When a club speed calculated based on the passage of the golf club detected by the second sensor S2 and the third sensor S3 is equal to or greater than a predetermined threshold value, the control part generates a trigger signal for starting to photograph the golf club. The measuring apparatus 10 can effectively suppress erroneous generation of the trigger signal.

Abstract: A golf ball 2 includes a core 4 and a cover 6 that is composed of an inner cover 8 and an outer cover 10. The core 4 has a radius of R (mm). A hardness Hs at a surface of the core 4 is greater than a hardness HL(R) when a linear approximation curve obtained by plotting a midpoint of each layer of the cover 6 in a thickness direction thereof in a graph in which a horizontal axis indicates a distance (mm) from a central point of the core 4 and a vertical axis indicates a hardness is represented by the following mathematical formula (I): HL(X)=A*X+B??(I), where X represents a distance (mm) from the central point of the core 4, HL(X) represents a hardness, and A and B represent a gradient and an intercept, respectively, of the linear approximation curve.

Abstract: A method and system for correcting a silhouette of a person extracted from an image by labeling each pixel as the person or the background are disclosed. The pixels in a target region are corrected by: a step in which, by the use of pixels in the target region labeled as the person, a person histogram is created; a step in which, by the use of pixels in the target region labeled as the background, a background histogram is created; a step in which, for each pixel in the target region, by the use of the person histogram, the background histogram and color data of each pixel in the target region, first connective costs of the pixel to the color data of the person and the background are calculated; and a step in which, for each pixel in the target region, a second connective cost of the pixel is calculated.

Abstract: An object of the present invention is to provide a golf ball having a low spin rate on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) base rubber, (b) an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, (c) a crosslinking initiator and (d) a carboxylic acid having a benzene ring and/or a salt thereof, provided that the rubber composition further contains (e) a metal compound in case of containing only (b) the ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms as the co-crosslinking agent.

Abstract: A section where the tip side partial bias layer exists in an axis direction of the shaft is defined as a section T; a section where the back end side partial bias layer exists in the axis direction of the shaft is defined as a section B; and a shaft section inserted into a hosel of a head in the axis direction of the shaft is defined as a section H. A part of the section T overlaps with the section H. An overlapping section TB in which the section T overlaps with the section B exists. The whole overlapping section TB is located on a back end Bt side of the shaft from the section H. A center position Px of the overlapping section TB is located on a tip side of the shaft from a center position Pc of the shaft.

Abstract: A set of iron-type golf clubs and a set of iron-type golf club heads are disclosed. The loft angles of the heads are gradually increased from the lowest numbered golf club to the highest numbered golf club in the set. Given that a coefficient of inertia of the head is the ratio Ms/M of a moment of inertia Ms (gram sq·cm) of the head around a horizontal axis extending in a toe-heel direction of the head passing through the center of gravity of the head, to the mass M (g) of the head, the coefficient of inertia is gradually increased with the increase in the loft angle, and the difference of the coefficient of inertia of the head of the highest numbered club from that of the lowest numbered club is 0.3 or more.

Abstract: A multi-piece golf ball includes a core composed of a center, an envelope layer and at least one cover. The center is formed from a composition containing at least one resin component and a basic metal salt of a fatty acid. The resin component is selected from a binary copolymer composed of an olefin and an ?,?-unsaturated carboxylic acid, an ionomer resin consisting of a metal ion-neutralized product of a binary copolymer composed of an olefin and an ?,?-unsaturated carboxylic acid, a ternary copolymer composed of an olefin, an ?,?-unsaturated carboxylic acid and an ?,?-unsaturated carboxylic acid ester, and an ionomer resin consisting of a metal ion-neutralized product of a ternary copolymer composed of an olefin, an ?,?-unsaturated carboxylic acid and an ?,?-unsaturated carboxylic acid ester. The envelope layer is formed from a composition containing a thermoplastic resin and/or a thermoplastic elastomer as a resin component.

Abstract: It is an object to provide a tubular body made from a novel fiber-reinforced epoxy resin material having improved strength. A tubular body made of a fiber-reinforced epoxy resin material according to the present invention is a tubular body made of a fiber-reinforced epoxy resin material comprising a cured product of an epoxy resin composition and a reinforcing fiber. The cured product of the epoxy resin composition has a swelling ratio of 20% by mass to 42.5% by mass in methyl ethyl ketone.

Abstract: A golf ball resin composition that is excellent in resilience includes (A) at least one resin component selected from the group consisting of (a-1) a binary copolymer composed of an olefin and an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms, (a-2) an ionomer resin consisting of a metal ion-neutralized product of a binary copolymer composed of an olefin and an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms, (a-3) a ternary copolymer composed of an olefin, an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and an ?,?-unsaturated carboxylic acid ester, and (a-4) an ionomer resin consisting of a metal ion-neutralized product of a ternary copolymer composed of an olefin, an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and an ?,?-unsaturated carboxylic acid ester, and (B) a basic metal salt of a fatty acid.

Abstract: A golf ball 2 includes a core 4, amid layer 6, a reinforcing layer 8, and a cover 10. The core 4 includes a center 12 and an envelope layer 14. The envelope layer 14 is formed by a rubber composition being crosslinked. The rubber composition includes a base rubber (a), a co-crosslinking agent (b), a crosslinking initiator (c), and an acid and/or a salt (d). The co-crosslinking agent (b) is: (b1) an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms; or (b2) a metal salt of an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms.

Abstract: An object of the present invention is to provide a golf ball excellent in a shot feeling and resilience. The present invention provides a golf ball resin composition comprising (A) at least one resin component selected from the group consisting of (a-1) a binary copolymer composed of an olefin and an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms, (a-2) an ionomer resin consisting of a metal ion-neutralized product of the binary copolymer, (a-3) a ternary copolymer composed of the binary copolymer components and an ?,?-unsaturated carboxylic acid ester, and (a-4) an ionomer resin consisting of a metal ion-neutralized product of the ternary copolymer components; and (B) a basic metal salt of a fatty acid, and having a spin-lattice relaxation time (T1) of 13C nucleus of 5.56 seconds or shorter measured by a High resolution solid state nuclear magnetic resonance (NMR) method.

Abstract: The present invention provides a golf ball resin composition comprising (A) an ionomer resin component and (B) a compound having an anionic part within a molecule thereof, wherein with respect to a metal ion contained in the golf ball resin composition, (A) the ionomer resin component and (B) the compound having the anionic part within the molecule thereof, following coordinate energies obtained by ab initio molecular orbital calculation method using a basis function B3LYP/6-31G(d) satisfy the following expression: 0.3?(A?C)/(B?C)?0.6, wherein coordinate energy A is the coordinate energy between the metal ion and the anionic part of (B) component, coordinate energy B is the coordinate energy between the metal ion and the carboxyl ion of (A) component, and coordinate energy C is the coordinate energy between the metal ion and the olefin of (A) the ionomer resin component.

Abstract: A head measuring method of the present invention includes: (a) preparing a golf club having a head having a plurality of markers provided thereon; (b) photographing the head by a camera disposed at a position, wherein a backward distance between the position and a center point of a ball is equal to or greater than 0, to obtain a head image near an impact; and (c) analyzing the head image to calculate a position and attitude of the head near the impact. Preferably, three or more combinations of the markers set such that the marker interval is equal to or greater than a head vertical width exist.

Abstract: A camera 10 photographs a golf player swinging a golf club to hit a golf ball and the golf club. Image data is obtained by photographing. A calculating part 16 extracts a plurality of frames from the image data. The calculating part 16 determines a check frame in which the golf player is in a predetermined posture from the plurality of frames. The calculating part 16 determines a contour of the golf player from the check frame. The calculating part 16 decides a swing from the contour of the golf player. An extreme value constituting the contour is determined in deciding the swing. A feature point is determined from the extreme value. The swing is diagnosed using the feature point.

Abstract: A golf club shaft has a tip end to which a golf club head is attached and a butt end to which a grip is attached, wherein the shaft is composed of a fiber reinforced resin having a fiber layer, the fiber layer contains a bias layer having bias fibers oriented at an angle with respect to an axial direction of the shaft, the bias layer includes a tip-side bias layer extending from the tip end toward the butt end and having a butt-side end terminating without reaching the butt end and a butt-side bias layer extending from the butt end toward the tip end and having a tip-side end terminating without reaching the tip end, and bias fibers in the tip-side bias layer has a tensile elastic modulus smaller than that of bias fibers of the butt-side bias layer.

Abstract: An object of the present invention is to provide a golf ball resin composition excellent in shot feeling and resilience. The golf ball resin composition includes (A) at least one resin component selected from the group consisting of (a-1) a binary copolymer composed of an olefin and an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms, (a-2) an ionomer resin consisting of a metal ion-neutralized product of the binary copolymer components, (a-3) a ternary copolymer composed of the binary copolymer components and an ?,?-unsaturated carboxylic acid ester, and (a-4) an ionomer resin consisting of a metal ion-neutralized product of the ternary copolymer components; and (B) a basic metal salt of a fatty acid, and having a storage modulus E? (Pa) and a loss modulus E? (Pa) satisfying a following expression; log(E?/E?2)??5.84 when measured in a tensile mode using a dynamic viscoelasticity measuring apparatus.