Golf ball resin composition and golf ball

A golf ball resin composition containing:

• (A) a thermoplastic resin having an infrared absorption peak in a region from 3200 cm−1 to 3600 cm−1, and
• (B) at least one resin component selected from the group consisting of (b-1) a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-2) a metal ion-neutralized product of a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-3) a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester, and (b-4) a metal ion-neutralized product of a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester,
• wherein the component (A) is a mixture of an ethylene-vinyl alcohol copolymer and a polyamide,
• a mass ratio of the component (A) to the component (B) ranges from 5/95 to 25/75, and
• when a relaxation modulus Er (−20° C., 9%) of the golf ball resin composition is measured under conditions of −20° C. and a strain of 9%, a relaxation curve is plotted with the relaxation modulus (MPa) as the vertical axis and a logarithm (ln(t)) of time (second) as the horizontal axis, and the relaxation curve is linearly approximated to obtain a linear approximation curve, the linear approximation curve has a slope in an absolute value of 7 or more.

A golf ball having a core, at least one intermediate layer covering the core, and a cover covering the at least one intermediate layer, wherein the at least one intermediate layer is formed from a golf ball resin composition containing:

• (A) a thermoplastic resin having an infrared absorption peak in a region from 3200 cm−1 to 3600 cm−1, and
• (B) at least one resin component selected from the group consisting of (b-1) a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-2) a metal ion-neutralized product of a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-3) a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester, and (b-4) a metal ion-neutralized product of a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester,
• wherein the component (A) is a mixture of an ethylene-vinyl alcohol copolymer and a polyamide, and a mass ratio of the component (A) to the component (B) ranges from 5/95 to 45/55,
• wherein when a relaxation modulus Er (−20° C., 9%) of the golf ball resin composition is measured under conditions of −20° C. and a strain of 9%, a relaxation curve is plotted with the relaxation modulus (MPa) as the vertical axis and a logarithm (ln(t)) of time (second) as the horizontal axis, and the relaxation curve is linearly approximated to obtain a linear approximation curve, the linear approximation curve has a slope in an absolute value of 7 or more, and
• wherein the at least one intermediate layer has a thickness of from 1.0 mm to 2.5 mm.

A golf ball having a core, at least one intermediate layer covering the core, and a cover covering the at least one intermediate layer, wherein the at least one intermediate layer is formed from a golf ball resin composition containing:

• (A) a thermoplastic resin having an infrared absorption peak in a region from 3200 cm−1 to 3600 cm−1, and including a thermoplastic resin having a hydroxyl group, and a thermoplastic resin having an amino group and/or a thermoplastic resin having an imino group, and
• (B) at least one resin component selected from the group consisting of (b-1) a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-2) a metal ion-neutralized product of a binary copolymer composed of an olefin and an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, (b-3) a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester, and (b-4) a metal ion-neutralized product of a ternary copolymer composed of an olefin, an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and an α,β-unsaturated carboxylic acid ester,
• wherein the thermoplastic resin having the hydroxyl group is at least one member selected from the group consisting of an ethylene-vinyl alcohol copolymer having the ethylene component in an amount of from 15 mole % to 60 mole %, a partially saponified product of an ethylene-vinyl acetate copolymer and a polyvinyl alcohol,
• a mass ratio of the component (A) to the component (B) ranges from 5/95 to 45/55,
• when a relaxation modulus Er (−20° C., 9%) of the golf ball resin composition is measured under conditions of −20° C. and a strain of 9%, a relaxation curve is plotted with the relaxation modulus (MPa) as the vertical axis and a logarithm (ln(t)) of time (second) as the horizontal axis, and the relaxation curve is linearly approximated to obtain a linear approximation curve, the linear approximation curve has a slope in an absolute value of 7 or more, and
• the at least one intermediate layer has a thickness of from 1.0 mm to 2.5 mm.