Golf ball
AssigneeSumitomo Rubber Industries, Ltd.
InventorsDaijiro Kojima, Takahiro Shigemitsu, Takahiro Sajima
Life of this patent
Estimating the term…
Abstract
A golf ball can include a core, a mid layer, and a cover. An amount P(Na) of a sodium ion-neutralized ionomer resin in abase resin of the cover can be not greater than 5 parts by mass. The golf ball can satisfy the following mathematical formulas (1) and (2): Fm / ( Hm * Tm ) - Fc / ( Hc * Tc ) ≥ 3. , and ( 1 ) Mc * Tc ≥ 10. , ( 2 ) where Hm: hardness (Shore D) of the mid layer, Tm: thickness (mm) of the mid layer, Fm: bending stiffness (MPa) of the mid layer, Tc: thickness (mm) of the cover, Fc: bending stiffness (MPa) of the cover, and Mc: melt flow rate (g/10 min) of the cover at a temperature of 190° C. under a load of 2.16 Kg.
Claims15
A golf ball comprising:
- a core,
- a mid layer outside the core and whose material is a resin composition, and
- a cover outside the mid layer and whose material is another resin composition, wherein
- a principal component of a base resin of the resin composition of the mid layer is an ionomer resin,
- the cover has a hardness Hc (Shore D) of not greater than 50,
- a principal component of a base resin of the resin composition of the cover is an ionomer resin,
- an amount P(I) of the ionomer resin in the base resin of the cover is not less than 60 parts by mass per 100 parts by mass of the base resin,
- an amount P(Na) of a sodium ion-neutralized ionomer resin in the base resin of the cover is not greater than 5 parts by mass per 100 parts by mass of the base resin, and
- the golf ball satisfies the following mathematical formulas (1) and (2):
- Fm
- /
- (
- Hm
- *
- Tm
- )
- -
- Fc
- /
- (
- Hc
- *
- Tc
- )
- ≥
- 3.
- ,
- and
- (
- 1
- )
- Mc
- *
- Tc
- ≥
- 10.
- ,
- (
- 2
- )
- where
- Hm:
- hardness (Shore D) of the mid layer,
- Tm:
- thickness (mm) of the mid layer,
- Fm:
- bending stiffness (MPa) of the mid layer,
- Tc:
- thickness (mm) of the cover,
- Fc:
- bending stiffness (MPa) of the cover, and
- Mc:
- melt flow rate (g/10 min) of the cover at a temperature of 190° C. under a load of 2.16 Kg.
A golf ball comprising:
- a spherical core,
- a mid layer outside the core and whose material is a resin composition, and
- a cover outside the mid layer and whose material is another resin composition, the cover having a plurality of dimples on a surface thereof, wherein
- the cover has a thickness Tc of not greater than 1.20 mm,
- the cover has a hardness Hc (Shore D) of not greater than 50,
- a principal component of a base resin of the resin composition of the mid layer is an ionomer resin,
- a principal component of a base resin of the resin composition of the cover is an ionomer resin,
- an amount P(I) of the ionomer resin in the base resin of the cover is not less than 60 parts by mass per 100 parts by mass of the base resin,
- a ratio of an amount P(Zn) of a zinc ion-neutralized ionomer resin to the amount P(I) of the ionomer resin in the base resin of the cover is not less than 90%, and
- the golf ball satisfies the following mathematical formulas (1) and (2):
- Fm
- /
- (
- Hm
- *
- Tm
- )
- -
- Fc
- /
- (
- Hc
- *
- Tc
- )
- ≥
- 3.
- ,
- and
- (
- 1
- )
- Mc
- *
- Tc
- ≥
- 10.
- ,
- (
- 2
- )
- where
- Hm:
- hardness (Shore D) of the mid layer,
- Tm:
- thickness (mm) of the mid layer,
- Fm:
- bending stiffness (MPa) of the mid layer,
- Tc:
- thickness (mm) of the cover,
- Fc:
- bending stiffness (MPa) of the cover, and
- Mc:
- melt flow rate (g/10 min) of the cover at a temperature of 190° C. under a load of 2.16 Kg.
Dependencies are inferred from the claim text.