Golf ball

摘要

A golf ball includes a spherical core and a cover covering the spherical core, wherein the cover is formed from a polyurethane composition containing a polyurethane elastomer as a resin component, the polyurethane composition has a shear loss modulus G″ of more than 5.03×106 Pa and 1.17×108 Pa or less when measured in a shear mode using a dynamic viscoelasticity measuring apparatus at the conditions of the temperature of 0° C., and the oscillation frequency of 10 Hz, the golf ball has a hardness distribution that R2 of a linear approximate curve determined by a least-squares method is 0.95 or more, when plotting center hardness (JIS-C) of the spherical core, hardness (JIS-C) measured at intervals of 2.5 mm from the center of the spherical core, surface hardness (JIS-C) of the spherical core, and slab hardness (JIS-C) of the cover versus distances from the center of the spherical core.

主权项

1. A golf ball comprising a spherical core and a cover covering the spherical core,
wherein the cover is formed from a polyurethane composition containing a polyurethane elastomer as a resin component, the polyurethane elastomer is formed by using 1,4-bis(isocyanatomethyl)cyclohexane as a polyisocyanate component, and the polyurethane composition has a shear loss modulus G″ of more than 5.03×106 Pa and 1.17×108 Pa or less when measured in a shear mode using a dynamic viscoelasticity measuring apparatus under conditions including a temperature of 0° C., and an oscillation frequency of 10 Hz, and wherein the golf ball has a hardness distribution such that R2 of a linear approximate curve determined by the least-squares method is 0.95 or more, if the core center hardness (JIS-C), the core hardness (JIS-C) measured at intervals of 2.5 mm progressively away from the core center, the core surface hardness (JIS-C), and the slab hardness (JIS-C) of the cover surface are plotted versus distances from the core center to the surface of the golf ball.