Abstract: A first golf ball 2 includes a core 4, a mid-layer 6, and a cover 8. The core 4 includes a center 10 and an envelope layer 12. The mid-layer 6 includes a metal ion source (C) that can neutralize an ionomer resin. The mid-layer 6 has a melt flow rate (at 190° C. and 2.16 kg) of 4 g/10 minute or greater. The difference (H3?H1) between the JIS-C hardness H3 of the cover 8 and the JIS-C central hardness H1 of the center 10 is equal to or greater than 45. A second golf ball 22 includes a core 24, a mid-layer 28, and a cover 30. The mid-layer 28 has a melt flow rate (at 190° C. and 2.16 kg) of 4 g/10 minute or greater. Preferably, the mid-layer 28 includes a high melt viscosity resin (A), a low melt viscosity ionomer resin (B), and a metal ion source (C1).

Abstract: Golf ball 2 has spherical main body 4, mark layer 6 and paint layer 8. The main body 4 has spherical core 10, and cover 12 provided to cover this core 10. The cover 12 does not include titanium oxide. The cover 12 includes a fluorescent colorant. The main body 4 has a chroma saturation of equal to or greater than 25. The paint layer 8 is constituted with a resin composition. This resin composition includes composite particles. The composite particle has a nucleus, and a coat layer provided to coat this nucleus. The nucleus is constituted with mica, while the coat layer is constituted with titanium oxide. The amount of the composite particles is 2 parts by weight or greater and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 8.

Abstract: A golf ball 2 includes a core 4 and a cover 6 positioned outside the core 4. The cover 6 has a thickness of 0.2 mm or greater and 1.0 mm or less. The cover 6 is formed by injecting a resin composition from an injection molding machine into a mold. The product (M*V*T) of: a melt fluidity M (g/10 min) of the resin composition, which is measured at 190° C.; an injection rate V (cm3/sec) of the injection molding machine; and an injection time T (sec) of the injection molding machine, is equal to or greater than 500 and equal to or less than 1000. Preferably, in the golf ball 2, the melt fluidity M of the resin composition is equal to or greater than 15 g/10 min and equal to or less than 100 g/10 min.

Abstract: A first golf ball 2 includes a core 4, a mid-layer 6, and a cover 8. The core 4 includes a center 10 and an envelope layer 12. The mid-layer 6 includes a metal ion source (C) that can neutralize an ionomer resin. The mid-layer 6 has a melt flow rate (at 190° C. and 2.16 kg) of 4 g/10 minute or greater. The difference (H3-H1) between the JIS-C hardness H3 of the cover 8 and the JIS-C central hardness H1 of the center 10 is equal to or greater than 45. A second golf ball 22 includes a core 24, a mid-layer 28, and a cover 30. The mid-layer 28 has a melt flow rate (at 190° C. and 2.16 kg) of 4 g/10 minute or greater. Preferably, the mid-layer 28 includes a high melt viscosity resin (A), a low melt viscosity ionomer resin (B), and a metal ion source (C1).

Abstract: A first golf ball 2 includes a core 4, a mid-layer 6, and a cover 8. The core 4 includes a center 10 and an envelope layer 12. The mid-layer 6 includes a metal ion source (C) that can neutralize an ionomer resin. The mid-layer 6 has a melt flow rate (at 190° C. and 2.16 kg) of 4 g/10 minute or greater. The difference (H3?H1) between the JIS-C hardness H3 of the cover 8 and the JIS-C central hardness H1 of the center 10 is equal to or greater than 45. A second golf ball 22 includes a core 24, a mid-layer 28, and a cover 30. The mid-layer 28 has a melt flow rate (at 190° C. and 2.16 kg) of 4 g/10 minute or greater. Preferably, the mid-layer 28 includes a high melt viscosity resin (A), a low melt viscosity ionomer resin (B), and a metal ion source (C1).

Abstract: An object of the present invention is to provide a golf ball comprising a core and a cover, wherein the cover is made from a cover composition containing, as a resin component, a thermoplastic polyurethane (A) and a polyisocyanate mixture (B) in which a urethane prepolymer (b-1) having at least two isocyanate groups is dispersed in a thermoplastic resin (b-2) which does not substantially react with an isocyanate group; and wherein the cover composition has a slab hardness of more than 60 and not more than 75, and the cover has a thickness of 2.5 mm or less.

Abstract: Golf ball 2 has spherical core 4, cover 6 positioned outside the core 4, mark layer 8 and paint layer 10. The resin composition of the cover 6 includes composite particles. The composite particle has a nucleus and a coat layer. The nucleus is constituted with aluminum oxide. The coat layer is constituted with titanium oxide. The composite particles are flaky. The amount of the composite particles is 0.1 parts by weight or more and 15 parts by weight or less per 100 parts by weight of the base resin of the cover 6. The composite particles may be also dispersed in the paint layer 10. The amount of the composite particles in the paint layer 10 is 1 part by weight or more and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 10.

Abstract: Golf ball 2 has spherical main body 4, mark layer 6 and paint layer 8. The main body 4 has spherical core 10, and cover 12 provided to cover this core 10. The cover 12 does not include titanium oxide. The cover 12 includes a fluorescent colorant. The main body 4 has a chroma saturation of equal to or greater than 25. The paint layer 8 is constituted with a resin composition. This resin composition includes composite particles. The composite particle has a nucleus, and a coat layer provided to coat this nucleus. The nucleus is constituted with mica, while the coat layer is constituted with titanium oxide. The amount of the composite particles is 2 parts by weight or greater and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 8.

Abstract: An object of the present invention is to provide a golf ball excellent in fluidity, adhesion of the paint film, and repulsion. Another object of the present invention is to provide a golf ball which is excellent in durability and low-temperature durability.

Abstract: An object of the invention is to provide a golf ball excellent in the durability at the normal and low temperatures, flight distance, and shot feeling on the shots. Another object of the present invention is to provide a golf ball excellent in a direction stability on the shots. The present invention provides a golf ball comprising: a core consisting of at least one layer; and a cover covering the core and having a thickness ranging from 0.3 mm to 1.0 mm, wherein the cover is formed from a cover composition that contains as a resin component, (A) a highly elastic polyamide resin (B) a metal-neutralized product of binary copolymer and/or ternary copolymer, and (C) a resin having a polar functional group in a specific amount, and wherein the cover composition has a slab hardness ranging from 65 to 75 in Shore D hardness.

Abstract: An object of the invention is to provide a golf ball excellent in the durability at the normal and low temperatures, flight distance, direction stability and shot feeling on the shots. The present invention provides a golf ball comprising: a core consisting of a center having a diameter of 35 mm or less and a surrounding layer covering the center; at least one intermediate layer covering the core, said intermediate layer having a thickness ranging from 0.5 mm to 1.2 mm and a density of 1.10 g/cm3 or more; and a cover covering the intermediate layer and having a thickness ranging from 0.3 mm to 1.0 mm, wherein the cover is formed of a cover composition that has a slab hardness ranging from 65 to 75 in Shore D hardness and contains as a resin component; (A) a polyamide resin composition having a flexural modulus in a range from 700 MPa to 4,000 MPa and a melt flow rate (240° C., 2.16 kg) of 5.

Abstract: Golf ball 2 has a spherical center 10, a mid layer 12 covering this center 10, a reinforcing layer 6 covering this mid layer 12, and a cover 8 covering this reinforcing layer 6. Base polymer of the mid layer 12 is an ionomer resin. Base polymer of the cover 8 is a thermoplastic polyurethane elastomer. The cover 8 has a thickness Tc of equal to or less than 1.2 mm, and particularly equal to or less than 0.8 mm. The difference (Ho?Hc) between the central hardness Ho of the center 10 and the hardness Hc of the cover 8 is 1 or greater and 30 or less. The cover 8 has a hardness Hc of 15 or greater and 40 or less. The product (Tc·Hc) of the thickness Tc (mm) of the cover 8 and the hardness Hc of the cover 8 is equal to or less than 25.

Abstract: Golf ball 2 has spherical main body 4, mark layer 6 and paint layer 8. The main body 4 has spherical core 10, and cover 12 provided to cover this core 10. The cover 12 does not include titanium oxide. The cover 12 includes a fluorescent colorant. The main body 4 has a chroma saturation of equal to or greater than 25. The paint layer 8 is constituted with a resin composition. This resin composition includes composite particles. The composite particle has a nucleus, and a coat layer provided to coat this nucleus. The nucleus is constituted with mica, while the coat layer is constituted with titanium oxide. The amount of the composite particles is 2 parts by weight or greater and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 8.

Abstract: An object of the present invention is to provide a golf ball comprising a core and a cover, wherein the cover is made from a cover composition containing, as a resin component, a thermoplastic polyurethane (A) and a polyisocyanate mixture (B) in which a polyisocyanate (b-1) having at least three isocyanate groups is dispersed in a thermoplastic resin (b-2) which does not substantially react with an isocyanate group; and wherein the cover composition has a slab hardness of more than 60 and not more than 75 in Shore D hardness, and the cover has the thickness of 2.5 mm or less.

Abstract: Golf ball 2 has a center 8, a mid layer 10 and a cover 6. The base polymer of the mid layer 10 includes an ionomer resin as a principal component. The surface hardness H1s of the center 8 is greater than the hardness H2 of the mid layer 10. The Shore D hardness H3 of the cover 6 is equal to or greater than 57. The weight W2 of the mid layer 10 is greater than the weight W3 of the cover 6. The total weight (W2+W3) of the weight W2 of the mid layer 10 and the weight W3 of the cover 6 is 8.4 g or greater and less than 12.0 g. The total volume (V2+V3) of the volume V2 of the mid layer 10 and the volume V3 of the cover 6 is equal to or less than 10.0 cm3.

Abstract: An object of the present invention is to provide a golf ball comprising a core consisting of a center and at least one intermediate layer covering the center, and a cover covering the core, wherein the cover is made from a cover composition containing, as a resin component, a thermoplastic polyurethane (A) and a polyisocyanate mixture (B) in which a urethane prepolymer (b-1) having at least two isocyanate groups is dispersed in a thermoplastic resin (b-2) which does not substantially react with an isocyanate group; and wherein the cover composition has a slab hardness of more than 60 and not more than 75 in Shore D hardness, and at least one piece or one layer of the intermediate layer is formed from a low hardness intermediate layer composition which has a slab hardness of 40 or less in Shore D hardness.

Abstract: Golf ball 2 has spherical core 4, cover 6 positioned outside the core 4, mark layer 8 and paint layer 10. The resin composition of the cover 6 includes composite particles. The composite particle has a nucleus and a coat layer. The nucleus is constituted with aluminum oxide. The coat layer is constituted with titanium oxide. The composite particles are flaky. The amount of the composite particles is 0.1 parts by weight or more and 15 parts by weight or less per 100 parts by weight of the base resin of the cover 6. The composite particles may be also dispersed in the paint layer 10. The amount of the composite particles in the paint layer 10 is 1 part by weight or more and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 10.

Abstract: Golf ball 2 has spherical core 4, cover 6 positioned outside the core 4, mark layer 8 and paint layer 10. The resin composition of the cover 6 includes composite particles. The composite particle has a nucleus and a coat layer. The nucleus is constituted with aluminum oxide. The coat layer is constituted with titanium oxide. The composite particles are flaky. The amount of the composite particles is 0.1 parts by weight or more and 15 parts by weight or less per 100 parts by weight of the base resin of the cover 6. The composite particles may be also dispersed in the paint layer 10. The amount of the composite particles in the paint layer 10 is 1 part by weight or more and 30 parts by weight or less per 100 parts by weight of the base resin of the paint layer 10.

Abstract: A golf ball 2 includes a core 4 and a cover 6 positioned outside the core 4. The cover 6 has a thickness of 0.2 mm or greater and 1.0 mm or less. The cover 6 is formed by injecting a resin composition from an injection molding machine into a mold. The product (M*V*T) of: a melt fluidity M (g/10 min) of the resin composition, which is measured at 190° C.; an injection rate V (cm3/sec) of the injection molding machine; and an injection time T (sec) of the injection molding machine, is equal to or greater than 500 and equal to or less than 1000. Preferably, in the golf ball 2, the melt fluidity M of the resin composition is equal to or greater than 15 g/10 min and equal to or less than 100 g/10 min.

Abstract: An object of the invention is to provide a golf ball excellent in the durability at the normal and low temperatures, flight distance, direction stability and shot feeling on the shots. The present invention provides a golf ball comprising: a core consisting of a center having a diameter of 35 mm or less and a surrounding layer covering the center; at least one intermediate layer covering the core, said intermediate layer having a thickness ranging from 0.5 mm to 1.2 mm and a density of 1.10 g/cm3 or more; and a cover covering the intermediate layer and having a thickness ranging from 0.3 mm to 1.0 mm, wherein the cover is formed of a cover composition that has a slab hardness ranging from 65 to 75 in Shore D hardness and contains as a resin component; (A) a polyamide resin composition having a flexural modulus in a range from 700 MPa to 4,000 MPa and a melt flow rate (240° C., 2.16 kg) of 5.