The present invention provides a golf ball comprising a core of one or more layers and a cover of one or more layers which encases the core, wherein at least one layer of the cover is formed of the resin composition comprising (a′) a polyester resin and (b) an amine-containing polymer having a branched structure. In the golf ball of the present invention, the adhesion property between the core and each cover layer adjacent to the core can be improved and the excellent durability can be obtained.

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.

Golf ball molds and methods for molding golf balls, particularly golf balls having thermoplastic polyurethane covers, are provided. The molds and methods are particularly suitable for manufacturing covers for golf balls. Multi-piece golf balls having inner cores, outer cores, inner covers, and intermediate layers can be made. Retractable pins are used for holding the golf ball within the mold, wherein each retractable pin has a primary vent section, secondary vent section, and tertiary vent section for removing air and other gasses from the interior spherical cavity of the mold.

In a golf ball having a core, a cover and at least one intermediate layer between the core and the cover, the core is made of a material molded under heat from a rubber composition that includes (a) a base rubber, (b) a co-crosslinking agent which is an α,β-unsaturated carboxylic acid and/or a metal salt thereof, (c) an organic peroxide, (d) water, and (e) an antioxidant which is a benzimidazole of a specific formula and/or a metal salt thereof. The core and ball have compressive deformations within specific respective ranges when subjected to given loading conditions. This golf ball exhibits a low spin rate on shots, enabling the flight performance of the ball to be improved.

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.

Multi-layered golf balls having at least one layer made of a foamed silicone composition are provided. Multi-layered golf balls having at least one layer made of non-foamed silicone elastomer composition also are provided. For example, three-piece, four-piece, and five-piece golf balls containing different core and cover structures can be made. The foamed silicones have good thermal stability and durability without sacrificing resiliency. The non-foamed silicone elastomers 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.

Dual core golf ball constructions achieving consistent and repeatable concentricity by incorporating/using an assembly of dual core components comprising a solid spherical inner core component and three outer core components that are collectively compression molded about the solid spherical inner core component to create an outer core layer thereabout. The three outer core components include a first half-shell, a second half-shell; and a ring-shaped securing plate such that the solid spherical inner core component is immovably centered within the outer core layer. Each of the first half-shell, the ring-shaped securing plate, and the second half-shell is comprised of the same rubber composition(s) and possess strong cohesive and adhesive bonds at parting lines between the three molded assembly parts and collectively create an outer core layer having one or more uniform property profile, such as a hardness gradient throughout, without interruption at parting lines between the three outer core components.

The presently disclosed subject matter is directed to a golf ball providing improve play characteristics. The disclosed golf ball includes an outer cover comprising a plurality of divots. The disclosed golf ball further includes a central core comprising one or more lightweight materials, such as aerogel. The combination of the lightweight core and the unique divots enable the golf ball to go farther and straighter when hit by the golfer, thereby providing increased performance.

Golf balls having covers made of thermoplastic polyurethane compositions are provided. Multi-piece golf balls can be made. Polyurethane primer coatings and polyurethane top-coatings are applied to the thermoplastic polyurethane cover. Different coating methods can be used. Isocyanate-rich and polyol-rich polyurethane coatings can be applied. In one embodiment, the golf ball can be treated with a multi-functional isocyanate prior to applying the coatings. The polyurethane cover composition and surface coatings can further include catalysts, ultraviolet (UV)-light stabilizers, and other additives. Heat is used to cure the coatings. The coating methods have many benefits and the finished balls have good physical properties.

Golf balls including a plurality of radar detectable marks disposed on any single layer or among two or more layers thereof are provided. When all of the radar detectable marks present on any layer of the ball are radially projected onto the outer surface of the ball, the resulting overall pattern of projected radar detectable marks includes a series of three or marks located on a 1.5 mm wide great circle band on the outer surface of the ball.