Golf ball

• US 5,792,009 A
• Filed: 02/12/1997
• Issued: 08/11/1998
• Est. Priority Date: 02/16/1996
• Status: Expired due to Term

• Current Assignee: Bridgestone Sports Co Limited (Bridgestone Corporation)
• Original Assignee: Bridgestone Sports Co Limited (Bridgestone Corporation)
• Inventors: Maruko, Takashi
• Primary Examiner(s): Marlo, George J.
• Application Number:
  US08/797,944
• Time in Patent Office: 545 Days
• Field of Search: 473/357, 473/377, 473/373, 473/374, 473/359, 473/372, 273/DIG. 20, 273/230
• US Class Current: 473/359
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: A63B 37/0039 characterised by the material
• CPC Class Codes: A63B 37/0053 Thread wound
• CPC Class Codes: A63B 37/00621 Centre hardness
• CPC Class Codes: A63B 37/0064 Diameter
• CPC Class Codes: A63B 37/0066 Density; Specific gravity
• CPC Class Codes: A63B 37/0067 Weight; Mass
• CPC Class Codes: A63B 37/0075 Three piece balls, i.e. cover, intermediate layer and core

Abstract

In a golf ball comprising a solid or wound core and a cover, the solid core or a center of the wound core is prepared by molding and vulcanizing a rubber composition comprising 100 parts by weight of base rubber and 10-120 parts by weight of a weight adjuster having a mean particle size of 30-1,000 μm and a specific gravity of 4-19.1. The solid core or center is improved in restitution and the ball will fly a longer distance.

Claims

1. A golf ball comprising:

a core and a cover, wherein the core is a solid core or a center of a wound core that is prepared by molding and vulcanizing a rubber composition comprising 100 parts by weight of base rubber and at least 10 parts by weight of a weight adjuster having a mean particle size of 30 to 1,000 μ

m and a specific gravity of at least 4.

2. The golf ball of claim 1 wherein said weight adjuster has a hardness of at least 3.5 on Mohs scale.

3. The golf ball of claim 1 wherein said rubber composition has a specific gravity in the range of 1.15 to 1.8.

4. The golf ball of claim 1 wherein said weight adjuster is at least one member selected from the group consisting of zirconium silicate, barium sulfate, chromite, and iron oxide.

5. The golf ball of claim 1 wherein said core is a solid core and said rubber composition comprises 10 to 25 parts of said weight of a particulate weight adjuster.

6. The golf ball of claim 1 wherein said core is a wound core and said rubber composition comprises 10 to 100 parts by weight of a particulate weight adjuster.

7. The golf ball of claim 1 wherein said core comprises a solid core and an overlying intermediate layer.

8. The golf ball of claim 1 wherein said core comprises a solid center and a thread rubber wound thereon.

9. The golf ball of claim 1 wherein said weight adjuster has a hardness of at least 5 on Mohs scale.

10. The golf ball of claim 1 wherein said core comprises a solid multipiece core having a diameter in the range of 34 to 41 mm.

11. The golf ball of claim 10 wherein said core has a weight in the range of 24 to 35 grams.

12. The golf ball of claim 10 wherein said core has a hardness at the center in the range of 50 to 80 measured by JIS-C.

13. The golf ball of claim 1 wherein said core is a wound core having a solid center with a diameter in the range of 26 to 35 mm.

14. The golf ball of claim 13 wherein the diameter of said wound core is in the range of 38 to 41 mm.

15. The golf ball of claim 14 wherein said wound core has a weight in the range of 35 to 38 grams.

16. The golf ball of claim 13 wherein said solid center has a hardness at its center in the range of 30 to 70 as measured by JIS-C.

17. The golf ball of claim 1 wherein said cover is a single layer having a hardness in the range of 43 to 65 on Shore D.

18. The golf ball of claim 1 wherein said cover is a multi-layer structure with an inner layer having a hardness in the range of 60 to 65 on Shore D and an outer layer having a hardness in the range of 43 to 53 on Shore D.

19. The golf ball of claim 1 wherein said cover is a single layer having a thickness in the range of 1 to 2.5 mm.

20. The golf ball of claim 1 wherein said cover is a multi-layer structure with an inner layer having a thickness in the range of 0.5 to 2 mm and an outer layer having a thickness in the range of 0.5 to 2 mm.