Moulded sound damping panel and production method of the same

A soundproofing panel, comprises a layer of a molded thermoplastic material with filler, and a foam (14) or felt layer, fastened to a fixed component, incorporates one-piece molded fastenings in the form of cavities shaped to receive anchoring projections (7) on the fixed component. The soundproofing panel, comprising a layer of a molded thermoplastic material with filler, and a foam (14) or felt layer, fastened to a fixed component, incorporates one-piece molded fastenings in the form of cavities shaped to receive anchoring projections (7) on the fixed component. Each cavity has a flared end (10) to facilitate insertion of the anchoring projection, and the panel has a circular or oblong bellows (9) round the fastening to facilitate alignment with the projection.