Multi-layer seat having different hardness and method for manufacturing the same

A method for manufacturing a seat wherein said seat is structured of a cushioning body which is integral with a surface material and has a shape defining an outline of said seat, said cushioning body comprising a first cushioning body and a second cushioning body, said first and said second cushion bodies being connected to each other, comprising steps of:

• placing at least one first fastener for connecting said first cushioning body with said second cushioning body on a surface of a bottom half of a pressure type mold, said pressure type mold being for pressure-molding said first cushioning body, said surface of said bottom half thereof being for defining a first contact surface for connecting with said second cushioning body;
• supplying a foamable mixture solution in said bottom half of said pressure type mold;
• disposing a surface material between said foamable mixture solution supplied in said bottom half of said pressure type mold and a top half thereof;
• closing both said halves of said pressure type mold when said foamable mixture solution is still in a state of flow but has completed a gas reaction thereof;
• placing at least one second fastener on a surface of a bottom half of a foaming mold so that said second fastener can be positioned corresponding to said first fastener, said foaming mold being for molding said second cushioning body, said surface of said bottom half thereof having a second contact surface corresponding to said first contact surface;
• supplying a foamable mixture solution in said bottom half of said foaming mold and then closing said bottom half of said foaming mold by a top half thereof;
• engaging said first fastener of said first cushioning body and said second fastener of said second cushioning body with each other.