A COMPOSITE SUBSTRATE USING A NON-WOVEN FABRIC FOR AN AUTOMOBILE AND MANUFACTURING METHOD THEREOF

PURPOSE: A method of manufacturing a composite substrate for vehicles based on non-woven fabrics is provided to lighten vehicles and to improve the sound absorbing and heat insulating property of a composite substrate by including a light foamed sheet in a core unit. CONSTITUTION: A composite substrate (10) for vehicles comprises a foamed sheet (5) based on a resin selected among a polypropylene-based resin, a polyethylene-based resin, and a mixture thereof, and non-woven fabrics (3a,3b). The non-woven fabrics are thermally bonded on both sides of the foamed sheet. In the non-woven fabrics, glass fibers and polypropylene-based fibers are mixed. A method of manufacturing the composite substrate comprises the steps of: injecting a foamed substance material composition containing a foaming agent and a resin selected among a polypropylene-based resin, a polyethylene-based resin, and a mixture thereof into an extruder; melt-extruding a compressed sheet; preparing a foamed sheet by foaming the foaming agent; preparing non-woven fabrics by mixing polypropylene fibers and glass fibers; and laminating and thermally bonding the non-woven fabrics on both sides of the foamed sheet.