Method of sound-deadening for vehicles

• Main Authors: WILLIAMS; EARL A, GILLILAND; ROBERT J
• Format: Patent
• Language: English
• Published: 22.03.1994
• Edition: 5
• Subjects: GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; PERFORMING OPERATIONS; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TRANSPORTING; VEHICLES IN GENERAL; VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISEPROVIDED FOR

For under hood sound-deadening of vehicles a molded sheet (14) of impregnated non-woven fabric sheet material having a weight in the range 0.5 to 0.75 kg/m2 and a density in the range of 350 to 425 kg/m3 is used. The material includes a blend of polyester staple fibers having an average decitex in the range 2.5 to 4.0 dtex typically 3.2 dtex. The impregnant includes 10 to 35% by dry weight carboxylated styrene-butadiene copolymer in which the styrene content is not less than 55%, 5 to 10% by dry weight carboxylated styrene-butadiene copolymer in which the styrene content is not more than 50%, 50 to 70% by dry weight mineral filler, and up to 3.5% by dry weight melamine formaldehyde resin. Pigment may also be added. The fabric sheet material is preferably clipped to the hood underside to provide a small air gap between the material and the hood, but alternatively the sheet material may be bonded by adhesive to the hood underside.