GOLF BALL HAVING MEDIUM POSITIVE GRADIENT QUOTIENT

摘要

A golf ball includes a core and a cover. The core has an outer surface, a geometric center, and a soft transition region adjacent to the outer surface. The soft transition region has a thickness of 4 mm or less, includes about 10 to 30% trans-polybutadiene isomer, and has a positive hardness gradient of about 10 Shore C or less. The cover layer has a hardness of about 50 Shore M or greater. The core has a positive hardness gradient of about 10 to 42 Shore C. A secondary gradient quotient, GQ′, from about 2.2 to 9.5, GQ′ being defined by the equation:;G′+T10×COR;where G′ is the core positive hardness gradient in Shore C, T is the percent of trans-polybutadiene isomer at the core outer surface, and COR is the coefficient of restitution of the core measured at an incoming velocity of 125 ft/s.

主权项

1. A golf ball comprising:
a core having an outer surface, a geometric center, and a soft transition region adjacent to the outer surface, the soft transition region having a thickness of about 4 mm or less, comprises about 10 to 30 percent of a trans-polybutadiene isomer, and has a first positive hardness gradient of about 10 Shore C or less; and an outer cover layer having a hardness of about 50 Shore M or greater; wherein the core has an outer surface hardness greater than a hardness at the geometric center to define a second positive hardness gradient of about 10 Shore C to 42 Shore C; and a secondary gradient quotient, GQ′, from about 2.2 to 9.5, GQ′ being defined by the equation:G′+T10×CORwhere G′ is the core positive hardness gradient in Shore C, T is the percent of trans-polybutadiene isomer at the core outer surface, and COR is the coefficient of restitution of the core measured at an incoming velocity of 125 ft/s.