Manufacturing method of integrated foam-molded product

A manufacturing method of an integrated foam-molded product which injects a polyurethane foam raw material into a mold to foam the polyurethane foam raw material and integrates an integration target disposed in the mold with a polyurethane foam layer, the method comprising:

• thermally deforming the integration target by foaming heat generated at the time of the foaming of the polyurethane foam raw material to mold the integration target into a predetermined shape, and obtaining an integrated foam-molded product in which the integration target is integrated with the polyurethane foam layer,
• wherein the integration target is made of a three-dimensional structure having air permeability and comprising a three-dimensional knitted fabric having a pair of ground knitted fabrics and connecting yarns knitted back and forth between the ground knitted fabrics, wherein the integration target is molded into the predetermined shape by the thermal deformation along the inner surface of the mold while a pressure of gas generated at the time of the foaming of the polyurethane foam raw material is used for shape retention of the three-dimensional structure,
• integrating the three-dimensional structure with the polyurethane foam layer in the mold while suppressing an entrance of the polyurethane foam raw material into gaps between the connecting yarns through the ground knitted fabric by the pressure of the gas, and
• joining a skin layer to at least part of the three-dimensional knitted fabric to provide the integration target as a skin layer joined three-dimensional structure,
• wherein as the three-dimensional knitted fabric, a gray fabric not having undergone a heat setting process is used, and
• wherein, when the skin layer is joined to the gray fabric of the three-dimensional knitted fabric, the skin layer is joined so as to have a slack relatively to the gray fabric between joined portions.