Patent ID: 11944875
Assignee: ACUSHNET COMPANY
Field: Furniture, games (Other fields)
Classification: CPC A | IPC A

Claim 12:
13. A golf ball, comprising:
a dual core comprising an outer core layer disposed over an inner core layer, the inner core layer having a geometric center hardness less than a surface hardness to define a first positive hardness gradient and the outer core layer having an inner surface hardness less than an outer surface hardness to define a second positive hardness gradient,
wherein the outer core layer and the inner core layer are each formed of a rubber composition cured under heat, the rubber composition comprising:
a base rubber comprising polybutadiene rubber having a 1,4 cis-bond content of at least 90 percent,
dicumyl peroxide,
zinc diacrylate,
calcium sulfate dihydrate in an amount of about 1 phr to about 3.9 phr, and
an additive selected from zinc pentachlorothiophenol, zinc oxide, barium sulfate, or combinations thereof, and

wherein the geometric center hardness is from about 40 Shore C to about 70 Shore C and the surface hardness is from about 75 Shore C to about 105 Shore C, and each of the first positive hardness gradient and the second positive hardness gradient is at least 34 Shore C units;

an inner cover layer surrounding the core; and
an outer cover layer disposed about the inner cover layer.