Abstract:
An object of the present invention is to provide a golf ball traveling a great distance on driver shots. The present invention provides a golf ball comprising a constituting member formed from a rubber composition containing (a) a base rubber, (b) an α, β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, and (c) an crosslinking initiator, wherein (b) the α, β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or the metal salt thereof meets the following conditions (1) and (2) in a volume based distribution, when measuring a particle size thereof with a laser diffraction particle size analyzer; (1) a mode particle size is more than 10 μm and 50 μm or less, and (2) a volume ratio of particles having a particle size ranging from 6 μm to 300 μm is 60% or more.
Abstract:
Provided is a golf club head that is able to suppress lowering of the pitch of a ball hitting sound. The golf club head according to the present invention includes a crown portion, a face portion, and a sole portion having at least one recessed portion. The recessed portion is configured to house a weight member such that the weight member does not protrude externally. The sole portion is provided with a placement region connected to the face portion and to be at least partially placed on a placement surface in a reference state, and a rear region arranged further to a back side in a face-back direction than the placement region and in which the recessed portion is arranged. The rear region inclines upward relative to the placement region toward the back side.
Abstract:
Provided is a golf club head that includes a face portion for hitting a ball. The face portion has a thick portion that includes a face center, and a peripheral portion that is thinner than the thick portion and surrounds the thick portion. The thick portion extends along a central axis line, and has a recessed portion on at least one side of the central axis line so that a central region of the thick portion along the central axis line is recessed more toward the central axis line than parts of the thick portion on two sides of the central region along the central axis line. Note that the central axis line extends in a top-sole direction or in a direction inclined from a toe side toward a heel side along a direction from a sole side toward a top side.
Abstract:
A putter-type golf club head that, when oriented in a reference position, includes a blade portion having a striking face, a top line, and a sole, the striking face in turn including a face center. The club head further includes a rear portion in communication with, and rearward of, the blade portion, and it includes an alignment element rearward of, and recessed toward the sole from, the top line. The alignment element defines a virtual center line segment oriented in a substantially front-to-rear direction at a height between 19 mm and 24 mm from a lowermost point of the sole, the center line segment having a length no less than 34 mm and being not spaced more than 10 mm from a virtual vertical plane passing through the face center and extending generally perpendicular to the striking face. A width of the club head is no less than 3.0 in.
Abstract:
An object of the present invention is to provide a golf ball traveling a great distance on driver shots and on iron shots. The present invention provides a golf ball comprising a spherical core including an inner layer and an outer layer, and a cover, wherein a difference (HX+1−HX−1) between a hardness (HX+1) at a point outwardly away in a radial direction from a boundary between the inner layer and the outer layer of the spherical core by 1 mm and a hardness (HX−1) at a point inwardly away in the radial direction from the boundary between the inner layer and the outer layer of the spherical core by 1 mm is 0 or more in Shore C hardness, a surface hardness (HX+Y) of the spherical core is more than 65 in Shore C hardness, an angle α of a hardness gradient of the inner layer is 0° or more, a difference (α−β) between the angle α and an angle β of a hardness gradient of the outer layer is 0° or more, a thickness of the cover is 3 mm or less, a difference (Hc−Hx+y) between a hardness (Hc) of the cover and the surface hardness (HX+Y) of the spherical core is 2 or more in Shore C hardness, and the cover has a highest hardness among the constituent members of the golf ball.
Abstract:
A golf ball 2 includes a core 4, a mid layer 6, a cover 8 and a paint layer 10. The core 4 includes a center 12 and an envelope layer 14. The golf ball 2 satisfies the following mathematical formulas. In the mathematical formulas, Hm represents a Shore D hardness of the mid layer, Hc represents a Shore D hardness of the cover, and Hb represents a Shore D hardness of the surface of the golf ball. The golf ball 2 has a large number of dimples 16 on a surface thereof. The number of planes that can divide a pattern of the dimples so that divided patterns are mirror symmetry to each other is one. Hc≦49 Hm−Hc≧15 Hm−Hb≦2
Abstract:
A device is provided with an obtaining unit, a specifying unit, and a determination unit. The obtaining unit obtains measurement data in which the golfer has performed a test-hit of at least one number of a golf club for each type of golf club from among the multiple types of golf clubs. The specifying unit specifies a relationship of correspondence between a loft angle and a flight-distance for each type of golf club based on the measurement data. The determination unit determines, based on the relationship of correspondence, a type of golf club having a large flight-distance with respect to a loft angle as a best-match type, which is a type of golf club best matched to the golfer.
Abstract:
An object of the present invention is to provide a material for obtaining a golf ball having excellent shot feeling and flight distance. The present invention provides a golf ball resin composition having a ratio (flexural elastic modulus/slab hardness) of a flexural elastic modulus (MPa) to a slab hardness (Shore D hardness) in a range from 3 to 5, and containing, as a resin component, (A) a polyamide resin, (B) at least one selected from the group consisting of (b-1) a binary copolymer, (b-2) a metal ion-neutralized product of a binary copolymer, (b-3) a ternary copolymer and (b-4) a metal ion-neutralized product of a ternary copolymer, and (C) a thermoplastic elastomer.
Abstract:
An object of the present invention is to provide a golf ball having excellent shot feeling and flight distance. The present invention provides a golf ball comprising a spherical core, a first resin layer and a second resin layer, wherein the first resin layer is formed from a first resin composition containing (A) a polyamide resin, (B) a copolymer and/or a metal ion-neutralized product thereof, and (C) a thermoplastic elastomer, and having a ratio (flexural elastic modulus/slab hardness) of a flexural elastic modulus (MPa) to a slab hardness (Shore D hardness) in a range from 3 to 5; and the second resin layer is formed from a second resin composition containing (D) a polyamide resin, and (E) a copolymer and/or a metal ion-neutralized product thereof.
Abstract:
This method simulates a run which is a distance between a landing point and a final arriving point using an initial condition of a hit ball and an actually measured falling condition. Preferably, the initial condition includes initial side spin. Preferably, the falling condition is a falling velocity. Preferably, a calculation formula of the run is a quadratic function having the initial condition and the falling condition as variables. Preferably, when the run is defined as Dr (yard); a target direction component of the falling velocity is defined as Vx (m/s); a vertical direction component of the falling velocity is defined as Vy (m/s); and the initial side spin is defined as S (rpm), the run is calculated according to the following formula: Dr=Ci×Vx2−C2×Vx+C3×Vy2+C4×Vy−Cs×S+C6.