Patent ID: 8349245

Claim:
A method of producing a vehicle interior panel having a hollow double-walled structure made of thermoplastic comprising: blow molding with a pair of mold halves including a first mold half with a shape transfer surface having a three dimensional pattern, and a second mold half, clamping a cover material being formed by at least a double-layer structure arranged between a cavity of said first mold half and a parison of thermoplastic such that a resin sheet layer without a through hole and without a three dimensional pattern faces a cavity of said first mold half, said cavity having a shape transfer surface with a three dimensional pattern, bonding a non-woven fabric layer whose weight per area is no more than 250 g/cm 2 to the parison introducing a pressurized fluid into the parison to press the cover material and the parison against a cavity surface, thereby integrally laminating said cover material having an average thickness of the cover material being not more than 2.0 mm (0.078 in), tensile modulus of the cover material being lower than 500 kg/cm 2 (7.11 ksi) at 100° C. (212° F.), a tensile strength at yield point of the cover material being not more than 50 kg/cm 2 (0.711 ksi) at 100 ° C. (212° F.) to an outer surface of a first wall of the panel having the hollow double-walled structure and transferring said three dimensional pattern of said first mold half to said resin sheet layer such that said three dimensional pattern is a plurality of protrusions disposed in a pattern impressed upon a surface of said resin sheet layer said protrusions having heights ranging from 0.5 - 2.5 mm (0.02-0.09 in) wherein an average thickness (a) of the vehicle interior panel is formed no more than 25.0 mm (0.98 in) and, the parting line is formed at a position located within a 35% range (b) of the average thickness of the panel from the surface of the first wall, and the parting line is formed within the range in which the average thickness is no more than 8.0 mm (0.315 in) from the surface of the first wall.