A golf ball for amateur golfers exhibits excellent flight characteristics when hit by the average golfer and also has a good feel at impact that is both soft and solid. The golf ball includes a core, an intermediate layer and a cover, and has coefficient of restitution and compressive deformation relationships that satisfy specific conditions.

In a golf ball having a core, an intermediate layer and a cover, the intermediate layer-encased sphere has a higher surface hardness than the ball. The core hardness profile in the ball is designed such that the core surface has a Shore C hardness value which is at least 27 higher than the Shore C hardness value at the core center, and the surface areas A to F calculated from hardness differences between positions located at specific distances in the core and differences between the specific distances satisfy a specific formula. This golf ball has an excellent flight performance when struck by skilled amateur golfers and professionals, and also has a good controllability on shots with an iron.

In a golf ball having a two-layer core which includes an inner core layer and an outer core layer and having a cover of one or more layer, the outer core layer is formed of an elastomer composition that includes specific amounts of (A) polybutadiene having a 1,2-bond content of 50 to 95%, (B) a photocurable monomer, oligomer or polymer, and (C) a photopolymerizable initiator. The outer core layer has a thickness of from 1.0 to 4.0 mm, and the two-layer core has a surface hardness on the JIS-C scale of from 75 to 95. The ball is provided with a hardness gradient at the core interior, which lowers the spin rate of the ball, has an improved durability to cracking, and production costs for the outer core layer are kept relatively low.

In a multi-piece solid golf ball having a core, an envelope layer, an intermediate layer and a cover, the core is formed primarily of a base rubber and has a diameter set in a specific range, the envelope layer, intermediate layer and cover are each formed of resin materials, and the envelope layer is formed into two layersan inner layer and an outer layer. The center and surface hardnesses of the core, the surface hardness of the inner envelope layer-encased sphere, the surface hardness of the outer envelope layer-encased sphere, the surface hardness of the intermediate layer-encased sphere and the surface hardness of the ball together satisfy a specific relationship. This ball achieves a satisfactory distance on full shots both with a driver and with irons, in addition to which it is superior in the short game and has a good feel at impact and an excellent scuff resistance.

A golf ball with a core comprising polybutadiene and graphene is disclosed herein. The golf ball has a single core comprising polybutadiene and graphene. Alternatively, the golf ball has a dual core with an inner core comprising polybutadiene and graphene. Alternatively, the golf ball has a dual core with an outer core comprising polybutadiene and graphene.

An object of the present invention is to provide a golf ball traveling a great flight distance. The present invention provides a golf ball comprising a spherical core and a cover covering the spherical core, wherein the golf ball has a ratio (t2/t1) of a time (t2) to a time (t1) of 1.05 or more in a hitting test using a driver (at a head speed of 40 m/sec), wherein the time (t1) is a time taken from a moment that the driver begins to contact with the golf ball to a moment that the golf ball reaches a maximum deformation amount, and the time (t2) is a time taken from the moment that the golf ball reaches the maximum deformation amount to a moment that the golf ball leaves the driver.

Method of making golf ball comprising aligning thermoformed depressions with dimpled mold cups and applying sufficient heat and suction to the thermoformed depressions without exposing any preselected subassembly to the heat and suction to soften the polymeric material of each thermoformed depression and draw air outward from a volume located between an inner surface of the dimpled mold cup and an outer surface of the thermoformed depression to form a thermoformed pre-form half-shell having an outer surface with the size, shape and contour of the inner surface of the dimpled mold cup(s) and an inner surface with the size, shape and contour of the outer surface of a preselected subassembly. Afterwards, a preselected subassembly is loaded between a pair of thermoformed pre-form half-shells and molded under sufficient short-term heat and suction to form the golf ball. The thickness of each thermoformed depression and thermoformed pre-form half-shell may be tapered.

A golf ball with improved durability is disclosed herein. The golf ball has a core comprising a polybutadiene material and methyl methacrylate, butadiene, styrene (MBS) with a weight percentage of MBS ranging from 0.5 to 5 weight percent of the core.

Multi-layered golf balls having at least one layer made from silicone (polysiloxane) elastomers; silicone (polysiloxane) elastomer/polyurethane blends; polycarbonate-polysiloxane blends and copolymers; and polycarbonate-polysiloxane/polyurethane blends are provided. For example, three-piece, four-piece, and five-piece golf balls containing different core and cover structures can be made. The polysiloxane compositions have good thermal stability and durability without sacrificing resiliency. The polysiloxane compositions also have high elongation, tensile strength, chemical/fluid-resistance, and weatherability properties. These compositions can be used to form any layer, for example, core, intermediate, or cover, in the golf ball.

A golf ball with a core comprising polybutadiene and graphene is disclosed herein. The golf ball has a single core comprising polybutadiene and graphene. Alternatively, the golf ball has a dual core with an inner core comprising polybutadiene and graphene. Alternatively, the golf ball has a dual core with an outer core comprising polybutadiene and graphene.