Abstract: An object of the present invention is to provide a golf ball showing an increased spin rate on approach shots under a wet condition while maintaining a spin rate on approach shots under a dry condition. The present invention provides a golf ball comprising a golf ball body and a paint film formed on a surface of the golf ball body, wherein the paint film has a multi-layered construction composed of two or more layers, and a difference (Min?Mout) between a 10% elastic modulus (Min) of an innermost layer of the paint film and a 10% elastic modulus (Mout) of an outermost layer of the paint film is 25 kgf/cm2 or more.

Abstract: An object of the present invention is to provide a golf ball having good spin performance on approach shots and good shot feeling as well as excellent stain resistance by precisely controlling physical properties of a paint film actually formed on a surface of a golf ball body. The present invention provides a golf ball comprising a golf ball body and a paint film formed on a surface of the golf ball body, wherein the paint film is such that a linear approximation curve obtained by a least square method has a slope in a range from 0.0015 to 0.0045 when a storage modulus (GPa) thereof measured by a nanoindentation method is plotted as a vertical axis against a measuring frequency (Hz) as a horizontal axis, and that an elastic modulus thereof measured by a nanoindentation method ranges from 0.040 GPa to 0.600 GPa.

Abstract: An object of the present invention is to provide a golf ball having good spin performance on approach shots and good shot feeling as well as excellent stain resistance by precisely controlling physical properties of a paint film actually formed on a surface of a golf ball body. The present invention provides a golf ball comprising a golf ball body and a paint film formed on a surface of the golf ball body, wherein the paint film is such that a linear approximation curve obtained by a least square method has a slope in an absolute value ranging from 0.0001 to 0.0020 when a loss tangent tan ? thereof measured by a nanoindentation method is plotted as a vertical axis against a measuring frequency (Hz) as a horizontal axis, and that an elastic modulus thereof measured by a nanoindentation method ranges from 0.040 GPa to 0.600 GPa.

Abstract: A golf ball 2 includes a main body 4 and a paint layer 6 positioned outside the main body 4. The main body 4 includes a spherical core 8, a mid layer 10 positioned outside the core 8, and a cover 12 positioned outside the mid layer 10. The paint layer 6 includes an inner layer 14 and an outer layer 16 positioned outside the inner layer 14. When an indentation depth (nm) is measured on a cross-section along a plane passing through a central point of the golf ball 2 when a force of 30 mgf is applied to the cross-section in a direction perpendicular to the cross-section, an indentation depth Di on a cross-section of the inner layer 14 is lower than an indentation depth Do on a cross-section of the outer layer 16.

Abstract: A golf ball 2 includes a core 4, a mid layer 6, a cover 8, and dimples 10. A Shore C hardness Hmc of the mid layer 6 is greater than a Shore C hardness Hs at a surface of the core 4. A Shore D hardness He of the cover 8 is less than a Shore D hardness Hm of the mid layer 6. Peak values and orders of maximum peaks of data constellations of the golf ball 2 are calculated. A minimum value of the peak values is not less than 95 mm. A minimum value of the orders is not less than 27, and a maximum value of the orders is not greater than 37. An average of the orders is not less than 30 and not greater than 34.

Abstract: A golf ball 2 includes a core 4, a mid layer 6, and a cover 8. A hardness H75 at a point to which a distance from a central point of the core 4 is 75% of a radius of the core 4 is greater than a hardness H0 at the central point of the core 4. A difference D1=(H75?H0) is not less than 10.0 and not greater than 27.0 in Shore C hardness. A hardness Hs at a surface of the core 4 is greater than the hardness H75. A difference D2=(Hs?H75) is not less than 0 and not greater than 6.5 in Shore C hardness. The hardness H75 is less than a Shore C hardness HmC of the mid layer 6. A Shore D hardness HmD of the mid layer 6 is greater than a Shore D hardness Hc of the cover 8.

Abstract: A golf ball 2 includes a main body 4 and a paint layer 6 positioned outside the main body 4. The main body 4 includes a spherical core 8, a mid layer 10 positioned outside the core 8, and a cover 12 positioned outside the mid layer 10. An indentation depth, measured when the paint layer 6 in a cross-section along a plane passing through a central point of the golf ball 2 is pressed by a force of 30 mgf in a direction perpendicular to the cross-section, is not less than 300 nm and not greater than 3000 nm. The paint layer 6 preferably has a thickness of not less than 5 ?m and not greater than 50 ?m.

Abstract: An object of the present invention is to provide a golf ball travelling a great flight distance on driver shots, exhibiting an excellent spin performance on approach shots under a dry condition and a wet condition, and showing an excellent shot feeling and durability. The present invention provides a golf ball comprising a golf ball body having a spherical core, an intermediate layer and a cover, and a paint film composed of two or more layers, wherein a 10% elastic modulus difference (Min?Mout) between an innermost layer and an outermost layer of the paint film is 25 kgf/cm2 or more.

Abstract: Provided is a golf ball comprising a spherical core including an inner layer and an outer layer, an intermediate layer and a cover, wherein a difference (HX+1?HX?1) is 0 or more in Shore C hardness, a surface hardness (HX+Y) of the spherical core is more than 70 in Shore C hardness, an angle ? of a hardness gradient of the inner layer is 0° or more, a difference (???) between the angle ? and an angle ? of a hardness gradient of the outer layer is 0° or more, the intermediate layer has a material hardness (Hm) ranging from 65 to 80 in Shore D hardness, and the intermediate layer has a highest hardness among the constituent members of the golf ball.

Abstract: A golf ball 2 includes a main body 4 and a paint film 6. The paint film 6 includes an inner layer 14 and an outer layer 16. A modulus Min of the inner layer 14 is higher than a modulus Mout of the outer layer 16. A difference (Min?Mout) is not less than 25 kgf/cm2. The golf ball 2 has a plurality of dimples 18. A ratio So of a sum of areas of the dimples 18 relative to a surface area of a phantom sphere of the golf ball 2 and a ratio Rs of a number of the dimples 18 each having a diameter of not less than 9.60% and not greater than 10.37% of a diameter of the golf ball 2, relative to a total number of the dimples 18, satisfy the following mathematical formula (1). Rs??2.

Abstract: A golf ball 2 includes a main body 4 and a paint film 6. The paint film 6 includes an inner layer 14 and an outer layer 16. A modulus Min of the inner layer 14 is higher than a modulus Mout of the outer layer 16. A difference (Min?Mout) is not less than 25 kgf/cm2. The golf ball 2 has a plurality of dimples 18. A ratio So of a sum of areas of the dimples 18 relative to a surface area of a phantom sphere of the golf ball 2 and a ratio Rs of a number of the dimples 18 each having a diameter of not less than 9.60% and not greater than 10.37% of a diameter of the golf ball 2, relative to a total number of the dimples 18, satisfy the following mathematical formula (1). Rs??2.

Abstract: A golf ball 2 includes a core 4, a mid layer 6, a cover 8 and a paint layer 10. The core 4 includes a center 12 and an envelope layer 14. The golf ball 2 satisfies the following mathematical formulas. In the mathematical formulas, Tm represents a thickness of the mid layer, Tcmin represents a minimum thickness of the cover, Tcmax represents a maximum thickness of the cover, and Tp represents a thickness of the paint layer. The golf ball 2 has a large number of dimples 16 on a surface thereof. The number of planes that can divide a pattern of the dimples so that divided patterns are mirror symmetry to each other is one. Tm>Tcmax?Tcmin>Tp (Tcmax?Tcmin)?0.15 mm 0.15?(Tp/Tcmin)?0.

Abstract: A golf ball 2 includes a core 4, a mid layer 6, a cover 8, and dimples 10. A difference DH in hardness between a surface and a central point of the core 4, a thickness Tm and a hardness Hm of the mid layer 6, a thickness Tc and a hardness Hc of the cover 8, and an amount of compressive deformation Sb meet the following mathematical formulas. (DH*Hm)/(Hc*Tc)>80 ((Sb*Tc)/(Hc* Hm*Tm))*1000>0.75 An area ratio So of dimples 10 and a ratio Rs of a number of the dimples 10 each having a diameter of equal to or greater than 9.60% but equal to or less than 10.37% of a diameter of the golf ball 2 meet the following mathematical formula (3). Rs??2.

Abstract: An object of the present invention is to provide a golf ball traveling a great distance on driver shots. The present invention provides a golf ball comprising a spherical core including an inner layer and an outer layer, wherein a difference (HX+1?HX?1) between a hardness (HX+1) at a point outwardly away in a radial direction from a boundary between the inner layer and the outer layer of the spherical core by 1 mm and a hardness (HX?1) at a point inwardly away in the radial direction from the boundary between the inner layer and the outer layer of the spherical core by 1 mm is 0 or more in Shore C hardness, a surface hardness (HX+Y) of the spherical core is more than 70 in Shore C hardness, an angle ? of a hardness gradient of the inner layer is 0° or more, a difference (???) between the angle ? and an angle ? of a hardness gradient of the outer layer is 0° or more, and the intermediate layer has a highest hardness among the constituent members of the golf ball.

Abstract: Golf ball 2 of the present invention has core 4, cover 10 situated on the external side of the core 4, and paint layer 16 provided to cover this cover 10. The base polymer of the cover 10 is a urethane resin. The base polymer of the paint layer 16 is a urethane resin. The cover 10 has a thickness Tc of 0.1 mm or greater and 0.7 mm or less. The paint layer 16 has a thickness Tp (mm) of 0.015 mm or greater and 0.040 mm or less. The ratio (Tp/Tc) is 0.021 or greater and 0.40 or less. Preferably, the paint layer 16 is formed with two or more layers 18 and 20. Preferably, the base polymer of the paint layer 16 is a two-pack type urethane resin or a two-pack type epoxy resin.

Abstract: A golf ball 2 includes an inner core 4, an outer core 6, a mid layer 8, a cover 10, and dimples 12. A diameter D1, a volume V1, a hardness H1o at a central point, a boundary inside hardness H1in, and a hardness difference De1 of the inner core 4; a volume V2 (mm3) and a hardness difference De2 of the outer core 6; a thickness Tm and a hardness Hm of the mid layer 8; and a thickness Tc and a hardness Hc of the cover 10 meet the following mathematical formulas. 1.0<V2/V1<7.0 De2?De1<0 600<(H1o*H1in)*(D1/2)/2<1000 620<Tc*Hc*Hm/Tm<900 The dimples 12 include a plurality of small dimples each having an area of less than 8.0 mm2.

Abstract: A golf ball 2 includes an inner core 4, an outer core 6, a mid layer 8, a cover 10, and dimples 12. A diameter D1, a volume V1, a hardness H1o at a central point, a boundary inside hardness H1in, and a hardness difference De1 of the inner core 4; a volume V2 (mm3) and a hardness difference De2 of the outer core 6; a thickness Tm and a hardness Hm of the mid layer 8; and a thickness Tc and a hardness Hc of the cover 10 meet the following mathematical formulas. 1.0<V2/V1<7.0 De2?De1<0 600<(H1o*H1in)*(D1/2)/2<1000 620<Tc*Hc*Hm/Tm<900 A dimple pattern of each hemisphere of the golf ball 2 includes three units rotationally symmetrical to each other.

Abstract: An object of the present invention is to provide a golf ball travelling a great flight distance on driver shots, exhibiting an excellent spin performance on approach shots under a dry condition and a wet condition, and showing an excellent shot feeling and durability. The present invention provides a golf ball comprising a golf ball body having a spherical core, an intermediate layer and a cover, and a paint film composed of two or more layers, wherein a 10% elastic modulus difference (Min?Mout) between an innermost layer and an outermost layer of the paint film is 25 kgf/cm2 or more.

Abstract: A golf ball 2 includes an inner core 4, an outer core 6, a mid layer 8, and a cover 10. A diameter D1, a volume V1, a hardness H1o at a central point, and a boundary inside hardness H1in of the inner core 4; a volume V2, a boundary outside hardness H2out, and a surface hardness H2s of the outer core 6; a thickness Tm and a hardness Hm of the mid layer 8; and a thickness Tc and a hardness Hc of the cover 10 meet the following mathematical formulas (1) to (4): 1.0<V2/V1<7.0 (1); ?2<H2s?H2out<2 (2); 600<(H1o+H1in)*(D1/2)/2<1000 (3); 620<Tc*Hc*Hm/Tm<900 (4). The cover 10 includes a polyrotaxane.

Abstract: A golf ball 2 includes a core 4, a mid layer 6, and a cover 8. A difference DH in hardness between a surface and a central point of the core 4; a thickness Tm (mm), a hardness Hm, and a volume Vm (mm3) of the mid layer 6; and a thickness Tc (mm), a hardness Hc, and a virtual volume Vc (mm3) of the cover 8 meet the following mathematical formulas. (DH*Hm)/(Hc*Tc)>63 3.0<((Vm*Hm)/(Vc*Hc))<7.5 A dimple pattern of each hemisphere of the golf ball 2 includes three units that are rotationally symmetrical to each other. A dimple pattern of each unit includes two small units that are mirror-symmetrical to each other.