A unique method of embedding an RFID chip into the core of a golf ball and using it in the application of a limited flight range ball for use in a range setup that can receive and monitor RFID signals is disclosed herein. The density of the core material is adjusted in relation to the mass of the RFID chip. The golf ball with an embedded RFID chip conforms to a mass limitation of the USGA.

A golf ball 2 includes a core 4 and a cover 6. A value V calculated by the following mathematical formula is equal to or less than 1080 Hz.

V=NF(2)22/3*NF(2)1

In the mathematical formula, NF(2)1 represents a secondary natural frequency of the core 4, and NF(2)2 represents a secondary natural frequency of the golf ball 2. A difference (H1sH1o) between a Shore C hardness H1s at a surface of the core 4 and a Shore C hardness H1o at a central point of the core 4 is equal to or greater than 10. An amount of compressive deformation Df1 of the core 4 is equal to or greater than 4.1 mm.

A golf ball 2 includes a core 4, a mid layer 6, and a cover 8. A difference DH in hardness between a surface and a central point of the core 4, a thickness Tm and a hardness Hm of the mid layer 6, a thickness Tc and a hardness Hc of the cover 8, and an amount of compressive deformation Sb of the golf ball 2 meet the following mathematical formulas (DH*Hm)/(Hc*Tc)>80 and ((Sb*Tc)/(Hc*Hm*Tm))*1000>0.75. A hardness Hc of the cover 8 is equal to or less than 40. A material of the cover 8 is a resin composition. The resin composition includes a polyurethane (A) and a polyrotaxane (B).

A golf ball comprising a core and a cover, wherein the core consists of: a solid inner core layer formed from a plasticized non-acid polymer composition PC.sub.p/N-A and having a diameter of 1.10 inch or less and a center Shore C hardness (H.sub.center) of 50 or less, one or more optional intermediate core layers, and an outer core layer formed from at least one of a thermoset rubber composition TR and a thermoplastic composition TP and having a thickness of 0.200 inches or greater and an outer surface Shore C hardness (H.sub.outer surface) of 70 or greater, wherein H.sub.outer surface>H.sub.center, and H.sub.outer surfaceH.sub.center40. In another embodiment, the center Shore C hardness (H.sub.center) is 40 or less, the outer surface Shore C hardness (H.sub.outer surface) is 85 or greater, and H.sub.outer surfaceH.sub.center45. In one embodiment, an intermediate layer is disposed between the outer core layer and the cover. The plasticized non-acid polymer composition PC.sub.p/N-A. may be formed from at least one non-acid polymer composition and at least one plasticizer.

A golf ball including a dual core comprising an inner core having a first outer surface, a geometric center, and a soft transition region adjacent to the outer surface, and an outer core layer having a second outer surface disposed about the inner core. An inner cover layer and an outer cover layer are formed over the core. The second outer surface is greater than the first outer surface to define a dual core overall positive hardness gradient of about 25 Shore C to 35 Shore C and has a secondary gradient quotient, GQ, defined by the equation:

[00001]$6\frac{G^{}+T}{10\mathrm{COR}}7$

where G is the overall 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 measured at an incoming velocity of 125 ft/s.

A golf ball includes a core having an outer surface, a geometric center, and a soft transition region adjacent to the outer surface. The soft transition region has a thickness of about 4 mm or less and includes about 10 to 45 percent of a trans-polybutadiene isomer. An outer cover layer has a hardness of about 50 Shore M or greater. The core outer surface hardness is greater than the hardness at the geometric center to define a positive hardness gradient of about 12 to 68 Shore C. The core has a secondary gradient quotient, GQ, of 4 to 13, GQ being defined by the equation:

[00001]$\frac{G^{}+T}{10\mathrm{COR}}$

where G is the positive hardness gradient in Shore C, T is the percent 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/.

A golf ball includes a unitary core having an outer surface, a geometric center, and a soft transition region adjacent to the outer surface. The core is formed from a substantially homogenous rubber composition. The golf ball also includes an inner cover layer and an outer cover layer. The soft transition region has a thickness of up to 4 mm and a negative hardness gradient of about 5 Shore C to about 15 Shore C. The unitary core has an overall negative hardness gradient of up to 20 Shore C.

The invention provides a method of manufacturing a golf ball having a core and a cover of one or more layer over the core, wherein an outermost layer of the cover is molded of a thermoplastic material selected from the group consisting of polyurethane, polyurea and mixtures thereof. The method includes at least the following steps (1) and (2): (1) treating a surface of the cover with an isocyanate compound; and (2) washing off and physically removing excess isocyanate compound by blasting the cover surface with a specific substance at high pressure.

An ultra-low compression golf ball is disclosed herein. The core preferably has a PGA compression less than 30. The mantle layer and cover have approximately the same thickness. The cover comprises a thermoplastic polyurethane material and has a specific gravity greater than the core and mantle layer. The golf ball has a PGA compression less than 75 and a COR of at least 0.780.

The present invention is directed to multi-layer golf balls including a layer formed from a composition comprising a relatively soft or low modulus HNP, a layer formed from a composition comprising a relatively hard or high modulus HNP, an inner cover layer formed from a thermoplastic composition, and an outer cover layer.