Patent ID: 6645089
Filing Date: 2003-11-11
Classification: A63B

Abstract:
A golf ball comprising:a core, wherein said core is formed by crosslinking a rubber composition, wherein said rubber composition comprises a base rubber, a co-crosslinking agent, organic peroxide and a filler; and a cover formed of a synthetic resin, wherein the modulus of elasticity of said cover is from 200 to 450 MPa; wherein the amount of compressive deformation of the core is larger than 3.6 mm; and a value of (T1/T2) is greater than 2.10 and is equal to or smaller than 2.50, wherein a direction of a counterclockwise rotation by 22 degrees with respect to a vertically upward direction is set to be a z direction, a direction of a counterclockwise rotation by 22 degrees with respect to a horizontally rightward direction is set to be an x direction, time series data on forces in the z and x directions which are applied to a load cell provided on a back face of a collision plate having a surface extended in the x direction when the golf ball impacts the collision plate in the vertically upward direction at a speed of 35 m/s are represented by Fn(t) and Ft(t) respectively, a time taken after a start of the impact before the Fn(t) is first changed from a positive number to zero is represented by said T1, and a time taken after the start of the impact before the Ft(t) is first changed from a positive number to a negative number is represented by said T2.