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 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 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: Golf ball 2 has spherical core 4, cover 6 situated on the external side of the core 4, and paint layer 8 situated on the external side of the cover 6. The cover 6 has a Shore D hardness of no greater than 61. The paint layer 8 has a Martens hardness of no greater than 2.0 mgf/?m2. The base polymer of the paint layer 8 is a polyurethane obtained by a reaction of a polyol with a polyisocyanate. The polyisocyanate contains a buret-modified form of hexamethylene diisocyanate. The cover 6 has a thickness of 0.3 mm or greater and 1.0 mm or less. The paint layer 8 has a thickness of 5 ?m or greater and 40 ?m or less.

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.