A golf ball including a thermoplastic inner core layer that has a geometric center hardness greater than its surface hardness to define a negative hardness gradient. An outer core layer is disposed about the inner core and is formed from a thermoplastic material and has an inner surface hardness substantially less than its outer surface hardness to define a positive hardness gradient. An inner cover layer is disposed about the outer core layer and an outer cover layer is disposed about the inner cover layer.

A laminate of the present invention includes a first member which contains a thermoplastic polymer and through which laser light is transmitted and a second member which contains a thermoplastic polymer and absorbs laser light, wherein the first member is directly bonded to the second member, and A represented by the formula 1: A=−9×D+Wa−45 is more than zero. D represents a distance between a Hansen solubility parameter of the thermoplastic polymer of the first member and a Hansen solubility parameter of the thermoplastic polymer of the second member, and Wa represents work of adhesion calculated from each surface free energy of the first member and the second member. Such a first member and a second member are firmly bonded to each other without using a bonding sheet.

A laminate of the present invention includes a first member which contains a thermoplastic polymer and through which laser light is transmitted and a second member which contains a thermoplastic polymer and absorbs laser light, wherein the first member is directly bonded to the second member, and A represented by the formula 1: A=−9×D+Wa−45 is more than zero. D represents a distance between a Hansen solubility parameter of the thermoplastic polymer of the first member and a Hansen solubility parameter of the thermoplastic polymer of the second member, and Wa represents work of adhesion calculated from each surface free energy of the first member and the second member. Such a first member and a second member are firmly bonded to each other without using a bonding sheet.

A polar functional group is added onto a surface of a metallic member. A resin member contains an adhesive functional group. The adhesive functional group and the polar functional group attract each other. A method for joining the metallic member and the resin member to each other includes: heating a junction between the metallic member and the resin member while pressing the metallic member and the resin member against each other with a first load; maintaining temperature of the junction higher than melting temperature of a resin that structures the resin member while pressing the metallic member and the resin member with each other with a second load smaller than the first load; and cooling the junction to temperature lower than the melting temperature while pressing the metallic member and the resin member against each other with a third load larger than the second load.

A polar functional group is added onto a surface of a metallic member. A resin member contains an adhesive functional group. The adhesive functional group and the polar functional group attract each other. A method for joining the metallic member and the resin member to each other includes: heating a junction between the metallic member and the resin member while pressing the metallic member and the resin member against each other with a first load; maintaining temperature of the junction higher than melting temperature of a resin that structures the resin member while pressing the metallic member and the resin member with each other with a second load smaller than the first load; and cooling the junction to temperature lower than the melting temperature while pressing the metallic member and the resin member against each other with a third load larger than the second load.

According to one aspect of the present invention, there is provided a hollow structure body having a hollow structure, in which a first shaped product constituted by a first fiber-reinforced resin material containing first reinforcing fibers and a first matrix resin and a second shaped product constituted by a second fiber-reinforced resin material containing second reinforcing fibers and a second matrix resin are combined, wherein in an arbitrary cross section in a direction perpendicular to an axial direction of the hollow structure, a ratio Sc/St between compressive strength Sc of a structure in the first shaped product and tensile strength St of a structure in the second shaped product satisfies formula (1):
(σc/σt)*(Hc/Ht)<(Sc/St)<(σt/σc)*(Hc/Ht)  formula (1).

According to one aspect of the present invention, there is provided a hollow structure body having a hollow structure, in which a first shaped product constituted by a first fiber-reinforced resin material containing first reinforcing fibers and a first matrix resin and a second shaped product constituted by a second fiber-reinforced resin material containing second reinforcing fibers and a second matrix resin are combined, wherein in an arbitrary cross section in a direction perpendicular to an axial direction of the hollow structure, a ratio Sc/St between compressive strength Sc of a structure in the first shaped product and tensile strength St of a structure in the second shaped product satisfies formula (1):
(σc/σt)*(Hc/Ht)<(Sc/St)<(σt/σc)*(Hc/Ht)  formula (1).

A vessel includes a vessel wall and an insulation assembly coupled to the vessel wall. The insulation assembly includes a stochastic foam material and a microtruss structure encased within the foam material. The microtruss structure includes a plurality of truss members interconnected at a plurality of nodes. Each truss member is in contact with the foam material such that the microtruss structure provides a structural core for the foam material.

Provided is a method of bonding two surfaces, which includes providing nitrogen or ammonia plasma to a plastic material where a polysiloxane contacted, and a construct manufactured therefrom.

Provided is a method of bonding two surfaces, which includes providing nitrogen or ammonia plasma to a plastic material where a polysiloxane contacted, and a construct manufactured therefrom.