Abstract: A golf ball 2 includes a spherical core 4, a mid layer 6 positioned outside the core 4, and a cover 8 positioned outside the mid layer 6. The core 4 includes a spherical center 10 and an envelope layer 12 positioned outside the center 10. The center 10 has a diameter of 1 mm or greater and 15 mm or less. The center 10 has a JIS-C hardness H1, at its central point, of 20 or greater and 50 or less. The difference (H4?H3) between the JIS-C hardness H4 of the core 4 at its surface and the JIS-C hardness H3 of the envelope layer 12 at its innermost portion is equal to or greater than 10. The cover 8 has a flexural modulus of 300 MPa or greater and 1000 MPa or less, and has a tensile modulus of 400 MPa or greater and 1500 MPa or less.

Abstract: A golf ball 2 has a hollow center 8, a mid layer 10, an inner cover 12 and an outer cover 14. The center 8 is formed by crosslinking a rubber composition. The rubber composition contains a natural rubber as a base polymer. The rubber composition contains sulfur. The mid layer 10 is formed by crosslinking a rubber composition. This rubber composition includes butadiene as a principal component of the base polymer. The center 8 has an inside diameter of 2 mm or greater and 13 mm or less. The center 8 has an outside diameter of 5 mm or greater and 15 mm or less. The center 8 has a surface JIS-C hardness H2 of 25 or greater and 55 or less. A difference (H4?H3) between a surface JIS-C hardness H4 of the mid layer 10 and a JIS-C hardness H3 of an innermost part of the mid layer is equal to or greater than 10.

Abstract: The invention relates on one hand to a celluloid-free table-tennis ball, preferably having a diameter of 38.5 to 48 mm, a weight between 2.0 and 4.5 grams, and a shell thickness (approximately) between 0.20 mm and 1.30 mm, where the shell is composed of plastic, whose principal component is an organic non-crosslinked polymer, which in its main chain has not only carbon atoms but also heteroatoms; and on the other hand also to a process of manufacturing a table-tennis ball of this kind, where mostly in a first step two or more shell parts are manufactured, these shell parts are joined in a subsequent step.

Abstract: The invention relates to a method for evaluating electronic impacts or shots of fired shots in a shooting range for sportsmen and for hunter training. The target to be shot at is provided as a light spot and is projected onto a target wall (1) via a light source in such a way that said target can move in all directions. An infrared camera (7) records the shooting image on the target wall (1) for evaluating the impact. The aim of the invention is to increase accuracy and reduce the evaluation time. Target co-ordinates arm detected while the target is being provided. Said target coordinates arm compared to the impact co-ordinates obtained by means of the impact evaluation. An impact is signalled when an impact falls short of a given divergence.

Abstract: A four-piece golf ball is disclosed herein. The golf ball has a core with an oxygen barrier boundary layer, a wound layer and a polyurethane cover. The core is preferably composed of polybutadiene material. The boundary layer is preferably composed of a blend of ionomers. The cover is preferably composed of a thermosetting polyurethane material. The golf ball has exceptional distance, exceptional feel and exceptional durability.

Abstract: A practice golf ball and its associated method of manufacture is claimed. The practice golf ball includes a hollow inner shell made of inexpensive molded plastic. The inner shell is molded so that the outer surface of the inner shell contains a dimple pattern. A first coating covers the inner shell. The first coating is applied as a liquid, wherein the first coating conforms to the dimple pattern on the inner shell. The first coating has a degree of elasticity greater than that of the plastic inner shell. A second coating covers the first coating. The second coating is also applied as a liquid, wherein the second coating conforms to the dimple pattern of the inner shell and the intervening first coating. The second coating has a degree of tear resistance greater than that of the plastic inner shell.

Abstract: A four-piece golf ball is disclosed herein. The golf ball has a core with an oxygen barrier boundary layer, a wound layer and a polyurethane cover. The core is preferably composed of polybutadiene material. The boundary layer is preferably composed of a blend of ionomers. The cover is preferably composed of a thermosetting polyurethane material. The golf ball has exceptional distance, exceptional feel and exceptional durability.

Abstract: The invention provides a golf ball having a cover, intermediate layers and/or a core comprising in whole or in part of water resistant polyurethane elastomers. The polyurethane elastomers may be blended with conventional materials employed to form golf balls, covers and intermediate layers.

Abstract: A four-piece golf ball is disclosed herein. The golf ball has a core with an oxygen barrier boundary layer, a wound layer and a polyurethane cover. The core is preferably composed of polybutadiene material. The boundary layer is preferably composed of a blend of ionomers. The cover is preferably composed of a thermosetting polyurethane material. The golf ball has exceptional distance, exceptional feel and exceptional durability.

Abstract: The present invention provides a hollow solid golf ball having excellent flight performance and soft and good shot feel at the time of hitting. The present invention relates to a hollow solid golf ball comprising a core having a hollow portion at the center of the core and a cover formed on the core, wherein the golf ball has a diameter of 42.92 to 45.47 mm, a moment of inertia of 83 to 105 g·cm2, and a deformation amount of 2.6 to 4.0 mm, when applying from an initial load of 10 kgf to a final load of 130 kgf.

Abstract: A unique golf ball and related methods of manufacturing are disclosed in which the golf ball comprises one or more metal mantle layers that define a hollow interior within the ball. The golf ball may also comprise an optional polymeric hollow spherical substrate inwardly disposed relative to the one or more metal mantle layers. The golf balls according to the present invention exhibit improved spin, feel, and acoustic properties. Furthermore, the one or more interior metal layers prevent, or at least significantly minimize, coefficient of restitution loss from the golf ball.

Abstract: A hollow golf ball comprising a hollow core and a cover layer that possesses good shot feel, an increased moment of inertia, and a high launch angle at the time of hitting. Immediately after impact, the hollow golf ball has a small spin amount. The specific hollow core reduces the rate of spin dumping between the ascending and descending of the ball, which results in increased flight distance. The hollow golf ball has a hollow core and a cover layer formed on the core, wherein the hollow core is composed of a hollow portion having a diameter of 5 to 30 mm and a core outer layer portion surrounding said hollow portion.

Abstract: This invention relates to methods of using cationic ionomers in the composition of inner layers of golf balls. Further, this invention relates to golf balls comprising one or more inner layers and which incorporate polyurethane or polyurea ionomers. The golf ball with inner layers comprising cationic ionomers has improved ball feel and initial velocity through the addition of an alkylating agent such as t-butyl chloride to introduce ionic interactions in the polyurethane or polyurea and thereby produce cationic type ionomers.

Abstract: The present invention is directed toward more durable golf ball cores and more durable golf balls. The golf balls of this invention comprise a cover and a core wherein the core may further comprise a center and one or more layers of a mantle disposed between the center and the cover. The core, the mantle or the layers of the mantle, comprise a mixture of one or more thermoset rubber materials and at least one compatible, modified, non-ionic polyolefin. The non-ionic polyolefin that is modified may be a homopolymer, copolymer, terpolymer, block copolymer or a mixture thereof that is present at about 0.5 to about 10 parts per hundred of the thermoset rubber material used in the core or core layer.

Abstract: The present invention is directed towards the novel use of polyether-amide block copolymer to form center core shells for use in liquid filled golf balls. Wound golf balls of the present invention which employ liquid filled centers formed from polyether-amide block copolymer exhibit the same or superior in-play characteristics such as initial velocity as compared to conventional wound golf balls.

Abstract: It is a main object of the present invention to impart a high impact resilience to a thread wound golf ball using a liquid center wherein a center bag is filled with a liquid, thereby improving a flying distance, while maintaining a good hit feeling and control properties.