PROCESS FOR MANUFACTURING PLASTIC SIDING PANELS WITH OUTDOOR WEATHERABLE EMBOSSED SURFACE

摘要

A process for making plastic siding panels, such asoutdoor weatherable vinyl panels with an embossed woodgrain pattern, comprises extruding a vinyl sheet, andoverlaying on the extruded sheet a flexible carrier sheethaving coated thereon (a) matte release layer bonded tothe carrier sheet, and (b) decorative coating on thematte release layer facing toward the extruded plasticsheet. An embossing roll applies pressure at elevatedtemperatures to transfer the decorative coating from thematte release layer and bond it to the extruded sheet,while the embossing roll embosses a three-dimensionalimpression pattern in the laminate transferred to theextruded sheet. The carrier sheet and its matte releaselayer are then released from the laminate transferred tothe vinyl sheet. The matte release layer transfers a low75° gloss level, preferably in the range of 8 to 12 glossunits, while enabling free release of the carrier fromthe embossed low gloss surface at elevated temperatures.In one embodiment, a multi-layer wood grain printedacrylic/polyvinylidene fluoride blended decorativecoating is simultaneously transferred to a vinylextrusion and embossed with a three dimensional woodgrain texture. A color coat behind wood grain printcoats contains pigment at a level that protects the vinylsubstrate from UV deterioration. The matte release layercontains a suspended wax which enhances forming the lowgloss surface while improving release of the matterelease layer from the transferred laminate. A siliconeresin in the matte release coat combines with the wax tofurther enhance release properties.