An automotive door inner, produced from polypropylene (PP) using MuCell foaming technology. The foam reduces the density of the part, allowing it to become thicker and stiffer without adding weight. Foaming usually leaves surface marks as a result of the flow of the gas during moulding. It is most visible in black parts. The polymer is modified with additives to reduce the effect and surface texture added to eliminate the visual impact altogether. In this way, a monomaterial part is possible, without any coating or covering necessary.