Synthetic resin skin material composite and method of producing synthetic resin skin material composite

A synthetic resin skin material composite, comprising:

• a urethane resin skin material comprising a urethane resin skin layer provided at one surface of a substrate;
• and
• a cushion layer that is placed at a surface on an opposite side of the substrate from the surface of the urethane resin skin material at which the urethane resin skin layer is provided, wherein the cushion layer consists of a polyurethane foam, wherein the polyurethane foam is a reaction product of a polyol and a polyisocyanate, wherein the polyol is a polyether polyester polyol;
• wherein the substrate includes a base cloth of a woven fabric or a knitted fabric;
• and
• wherein the urethane resin skin material has recesses at a side of the urethane resin skin layer, and each of the recesses has a depth in a thickness direction of the synthetic resin skin material composite, such that the recesses extend from the urethane resin skin layer into the cushion layer beyond an interface between the urethane resin skin material and the cushion layer that is present in a region without a recess.

A synthetic resin skin material composite, comprising:

• a urethane resin skin material comprising a urethane resin skin layer provided at one surface of a substrate, wherein the urethane resin skin layer is formed from a composition comprising a water-based polyurethane that is a homopolymer of a polyether or polycarbonate polyurethane, or that is a mixture or a copolymer of a polyether polyurethane and a polycarbonate polyurethane, in which from 0.01% to 10% of carboxyl groups in terms of mass ratio with respect to the water-based polyurethane are a part of the molecular chain of the water-based polyurethane;
• and
• a cushion layer that is placed at a surface on an opposite side of the substrate from the surface of the urethane resin skin material at which the urethane resin skin layer is provided;
• wherein the substrate includes a base cloth of a woven fabric or a knitted fabric;
• and
• wherein the urethane resin skin material has recesses at a side of the urethane resin skin layer, and each of the recesses has a depth in a thickness direction of the synthetic resin skin material composite, such that the recesses extend from the urethane resin skin layer into the cushion layer beyond an interface between the urethane resin skin material and the cushion layer that is present in a region without a recess;
• and
• wherein the synthetic resin skin material composite is an automotive interior part.

A method of producing a synthetic resin skin material composite, the method comprising:

• forming a urethane resin skin layer at one surface of a substrate, to yield a urethane resin skin material, wherein the substrate includes a base cloth of a woven fabric or a knitted fabric, and wherein the urethane resin skin layer is formed from a composition comprising a water-based polyurethane that is a homopolymer of a polyether or polycarbonate polyurethane, or that is a mixture or a copolymer of a polyether polyurethane and a polycarbonate polyurethane, in which from 0.01% to 10% of carboxyl groups in terms of mass ratio with respect to the water-based polyurethane are a part of the molecular chain of the water-based polyurethane;
• forming a cushion layer at a side of the urethane resin skin material at which the urethane resin skin layer is not provided, to yield a laminate of the urethane resin skin material and the cushion layer, wherein the cushion layer consists of a polyurethane foam;
• and
• placing the yielded laminate between a pair of molds comprising a first mold with an embossing die and a second mold without an embossing die, heating the first mold at a temperature in a range of from 130° C. to 160° C. and heating the second mold at a temperature in a range of from 140° C. to 200° C., and pressing protrusions of the embossing die of the first mold onto a side of the urethane resin skin layer of the laminate for embossing under a condition that tips of the protrusions of the embossing die of the first mold extend into the cushion layer, thereby forming recesses having depths such that the recesses extend into the cushion layer beyond an interface between the urethane resin skin material and the cushion layer.