A golf ball includes an inner core layer having a first surface hardness and a geometric center hardness. The center hardness is less than the first surface hardness to define a first positive hardness gradient of about 1 to 12 Shore C. An outer core layer has a second surface hardness. A cover layer is formed over the outer core layer. The second outer surface hardness is greater than the geometric center hardness to define a second positive hardness gradient of about 12 to 22 Shore C.

A golf ball includes an inner core layer having a first surface hardness and a geometric center hardness. The center hardness is less than the first surface hardness to define a first positive hardness gradient of about 1 to 12 Shore C. An outer core layer has a second surface hardness. A cover layer is formed over the outer core layer. The second outer surface hardness is greater than the geometric center hardness to define a second positive hardness gradient of about 12 to 22 Shore C.

Golf balls having a single or dual-layered solid core are provided. In one embodiment, the golf ball has dimensions and properties that do not conform to the rules of the United States Golf Association (USGA). For example, the ball weight; ball size; ball spherical symmetry; ball initial velocity; and/or ball overall distance may fall outside of the USGA standards. The dual-layered core can have an inner core comprising a thermoplastic composition and surrounding outer core comprising a thermoset composition. In another embodiment, the dual-layered core has an inner core comprising a thermoplastic composition and outer core comprising a thermoset composition. The thermoplastic composition preferably comprises an ethylene acid copolymer ionomer and plasticizer. The thermoset composition preferably comprises polybutadiene rubber. The ball further includes a cover of at least one layer.

An object of the present invention is to provide a golf ball having a novel core structure and traveling a great flight distance on driver shots. The present invention provides a golf ball comprising a core composed of a spherical center and an envelope layer and at least one cover layer disposed outside the core, wherein the spherical center has an internal hardness difference between a maximum hardness and a minimum hardness of less than 5 in JIS-C hardness, the envelope layer is formed from an envelope rubber composition containing (a) a base rubber, (b) an ,-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, (c) an crosslinking initiator and (d) an acid and/or a salt thereof, and the outermost cover layer has a highest hardness among the constituent members of the golf ball.

A mixed reality golf simulation and training system that can use, along with a user's existing standard golf equipment, a golf ball launch monitor to track the initial ball positional data, spin and acceleration, and simulate the complete ball path and location or use complete ball tracking data and displays the actual ball path and location. Mixed reality glasses allow the display of ball tracking data over the real world view and/or an immersive display of a simulated world view, depending on the user's head or view position. Golf simulation graphical views can include various options, including simulated or panoramic photographic views of a golf course, simulated graphics and data superimposed over a real world driving range view, or simple ball tracking data superimposed over a real world view at any location.

Biodegradable materials and methods of their manufacture. Certain embodiments of the biodegradable materials include a crustacean shell material, at least one of gelatin, glycerin, and sorbitol, and water, wherein the biodegradable material is characterized in that, when it is exposed to water for an extended period of time, the material at least partially decomposes. Particular embodiments may comprise additional components including sorbitol and glycerin in the case of biodegradable golf ball embodiments, for example.

Golf ball having a core and a cover of one or more layers, the core being formed of a material molded under heat from a rubber composition including a base rubber, an organic peroxide, and water and/or a metal monocarboxylate. Defining the tan slope as (tan .sub.10tan .sub.1)/(10%1%), where tan .sub.1 and tan .sub.10 are the loss tangents at dynamic strains of, respectively, 1% and 10% when the loss tangents of the core center and the core surface are measured at 12 C. and 15 Hz, the difference between the tan slopes at the core surface and the core center is larger than 0.002. Because a core material which undergoes little decrease in resilience over time and experiences little energy loss can be obtained, the golf ball maintains a good rebound, has a reduced spin rate and thus is able to achieve an increased distance.

Multi-layer golf balls having a hard, high compression center, a relatively soft intermediate layer, and a stiff outer cover layer, are provided. The outer surface hardness of the intermediate layer is less than that of both the center and the outer cover layer.

Multi-layer golf balls having a hard, high compression center, a relatively soft intermediate layer, and a stiff outer cover layer, are provided. The outer surface hardness of the intermediate layer is less than that of both the center and the outer cover layer.

The present invention is directed to golf balls consisting of a multi-layer core and a cover. The multi-layer core includes at least one layer formed from a relatively soft or low modulus HNP composition and at least one layer formed from a relatively hard or high modulus HNP composition.