Golf ball
AssigneeSumitomo Rubber Industries, Ltd.
InventorsYasuo Naito, Masayuki Onishi, Kazuyoshi Shiga, Takahiro Shigemitsu
Life of this patent
Estimating the term…
Abstract
An object of the present invention is to provide a novel golf ball having excellent spin performance 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 composed of at least one layer, wherein a base resin constituting an outermost layer of the paint film includes a polyurethane, and the polyurethane has a loss elastic modulus (E″) of 0.2×108 Pa or more at −50° C. and a loss tangent (tan δ) having a peak temperature of 0° C. or less, obtained by measuring dynamic viscoelasticity of the polyurethane under specific conditions.
Claims18
A golf ball comprising a golf ball body, and a paint film formed on a surface of the golf ball body and composed of at least one layer, wherein
- a base resin constituting an outermost layer of the paint film includes a polyurethane, and
- the polyurethane has a loss elastic modulus (E″) of 0.2×108 Pa or more at a temperature of −50° C. and a loss tangent (tan δ) having a peak temperature of 0° C. or less, obtained by measuring dynamic viscoelasticity of the polyurethane under following conditions:
- <measuring conditions>
- measuring mode:
- sine wave tensile mode
- measuring temperature range:
- −120° C. to 100° C.
- Temperature increasing rate:
- 3° C./min
- oscillation frequency:
- 10 Hz
- measuring strain:
- 0.05%.
Dependencies are inferred from the claim text.