Abstract: A seat cover comprises a knitting of a three-dimensional structure conforming in its external shape to that of a seat and including at least main portions, side portions and welt portions integrally knit into a one-piece form. The knitting further includes integrally knit portions covering overhang portions and corner portions of the seat and/or rear and bottom portions of a front back of the seat.

Abstract: A structure for securing the trim cover assembly of a seat back in an automotive seat is disclosed in which the seat back is formed in the back thereof with a slit extending along the internal periphery of the seat back. The end portions of a front-side trim cover assembly for covering the front side of the seat back are inserted through the slit and are fixed to the interior of the seat back. The securing portions of hard material disposed in the peripheral end portions of a back-side trim cover assembly for covering the back side of the seat back are inserted through the slit and thereafter, due to the tension of the back-side trim cover assembly, are engaged with the inner side of the slit.

Abstract: A method of manufacturing a cushion material by welding under heat a first layer to an adjoining second layer at necessary portions of the latter by use of a welding member having a plurality of pressure applying projections. The material of the second layer is deformed and molten and flows at temperatures higher than those of the material of the first layer. In the method, the surface portions of the first layer not engaged by the welding member and lying closer to the welding member and/or the welding member itself are cooled by cooling gas thereby welding the first layer to the second layer without giving rise to any appreciable thermal change on the surface of the first layer except the portions engaged by the welding member.