A golf ball comprising: (a) a core; (b) an inner mantle layer; (c) an intermediate mantle layer; (d) an outer mantle layer; and (e) at least one cover layer; wherein the core has a PGA compression of less than 70, and the core/inner mantle layer/intermediate mantle layer combined construct has a PGA compression of at least 30.

A golf ball comprising a core composed of a fully neutralized polymer material is disclosed herein. The golf ball also preferably has multiple mantle layers and a cover.

A method of producing a golf ball applies ultrasonic welding on two half shells to form at least one intermediate layer, at least one cover layer, or at least one intermediate layer and at least one cover layer. The ultrasonic welding may include pressing the two half shells together, delivering a high power electrical signal to a welding stack, and converting the high power electrical signal at the welding stack to ultrasonic energy. The converting may include converting the high power electrical signal into a mechanical vibration, modifying an amplitude of the mechanical vibration to generate a modified mechanical vibration, and applying the modified mechanical vibration to an interface of the two half shells to weld them together ultrasonically. Aspects also relate to golf balls, or one or more layers thereof, made using ultrasonic welding.

A method of producing a golf ball applies ultrasonic welding on two half shells to form at least one intermediate layer, at least one cover layer, or at least one intermediate layer and at least one cover layer. The ultrasonic welding may include pressing the two half shells together, delivering a high power electrical signal to a welding stack, and converting the high power electrical signal at the welding stack to ultrasonic energy. The converting may include converting the high power electrical signal into a mechanical vibration, modifying an amplitude of the mechanical vibration to generate a modified mechanical vibration, and applying the modified mechanical vibration to an interface of the two half shells to weld them together ultrasonically. Aspects also relate to golf balls, or one or more layers thereof, made using ultrasonic welding.

A golf ball comprising: (a) a core; (b) at least one mantle layer adjacent to the core; (c) an inner cover layer adjacent to the mantle layer; and (d) an outer cover layer adjacent to the inner cover layer, wherein the inner cover layer has a material Shore D hardness that is at least 3 less than the material Shore D hardness of the outer cover layer, and the inner cover layer has a thickness of less than 0.050 in.

Golf balls having cores with increased hardness gradients are provided. The cores have an increased “positive” hardness gradient (or a “hard-to-soft” hardness) where the outer surface of the core is harder than the center. The increased positive hardness gradient can be achieved by introducing a water-releasing agent into the core rubber formulation during the curing process. The resulting golf balls have reduced spin and sufficient impact durability.

Golf balls having cores with increased hardness gradients are provided. The cores have an increased “positive” hardness gradient (or a “hard-to-soft” hardness) where the outer surface of the core is harder than the center. The increased positive hardness gradient can be achieved by introducing a water-releasing agent into the core rubber formulation during the curing process. The resulting golf balls have reduced spin and sufficient impact durability.

The present invention provides methods for producing molded golf balls and the resultant balls. The methods of this invention involve producing foamed polyurethane covers and these methods help reduce dimple distortions and other surface imperfections. These golf balls contain an inner core and outer foamed polyurethane cover. One or more intermediate layers can be disposed between the core and cover. In one embodiment, a castable liquid polyurethane composition containing a foaming agent is dispensed into mold cavities, which are then pressed together to form a foam cover for the ball.

The use of a low molecular weight farnesene, poly(farnesene), and farnesene copolymer in a golf ball is disclosed herein. In a core, low molecular weight farnesene, poly(farnesene) or farnesene copolymer is blended with 1,4 polybutadiene or a polyalkenamer. In a mantle layer, low molecular weight farnesene, poly(farnesene), and/or farnesene copolymer can be blended with non- or partially neutralized copolymeric or terpolymeric ionomer(s). In a cover, low molecular weight farnesene, poly(farnesene), and farnesene copolymer can be blended with highly neutralized ionomer.

Golf ball comprising at least one layer that is comprised of a cured elastomeric composition comprising a mixture of an elastomeric composition and an organic peroxide-based curing composition; wherein the mixture at least partially contacts oxygen during curing.