Embossing of leather for steering wheel covers - by applying thermoplastic layer locally on underside to stabilise pattern when leather is stitched under tension

摘要

A flexible, slightly compressible material, particularly leather, is permanently embossed with a die. The underside of the embossed region is covered and filled by a hardenable synthetic material. The synthetic material can be a thermoplastic and embossing as well as application of the synthetic material can be carried out under heat. When used to cover vehicle steering wheels the warmed material is stretched round the wheel and stitched along the edge. The leather covering (2) of a steering wheel is embossed under heat so that in the embossed regions (3,4) the grain virtually disappears to give a smooth surface and locally (6,7) the leather is thinned. To stabilise the embossing and avoid it being stretched out when the leather covering is stitched under tension on to the steering wheel a thermoplastic material (8) is applied by a counter-die on the underside. The underlying polyurethane foam is cut away to accommodate the thickness of the thermoplastic backing so that the outer surface of the leather remains level round the embossing. USE/ADVANTAGE - The process is used to give permanently embossed letters on vehicle steering wheels.