Abstract: The thermoplastic filter plate is designed for a filter press comprising a plurality of the filter plates clamped together edgewise forming a plurality of filter chambers between themselves. Each filter plate has a press wall on one or both sides of it. This press wall is at least flexible in an edge region and is movable by action of a pressurizing medium into one of the filter chambers. Each of the filter plates includes unitarily a supporting wall and a compression chamber for the pressurizing medium acting on the press wall, the supporting wall being located between adjacent compression chambers. The press wall is made in one piece with a plate frame of the filter plate. The rigid plate frame is composed of a hard plastic material resistive to the closing pressure of the filter press and the press wall is composed of an elastic plastic material guaranteeing an easy adjustability and deformability.

Abstract: The press wall is provided for a filter element of a filter press comprising a plurality of filter elements clamped together edgewise forming filter chambers for the suspension to be filtered. A filter element carries on one or both sides a press wall is attached edgewise with it which is movable by a pressurizing medium into the filter chamber. Each press wall has a plurality of sectional projections overlayed with a filter cloth on their wall surfaces directed toward the filter chamber which form a drainage system under the filter cloth. The press wall has an edge adjacent an edge region facilitating its connection to the filter element and a wall strip extending along this edge region. The wall strip is bendable at least to the extent of the displacement of the press wall under pressure.

Abstract: A thermoplastic polyolefin substrate, preferably polyethylene or polypropylene, is joined to an ethylene-propylene polymer, preferably an ethylene-propylene-diene elastomer, by first locally preheating only selected portions of the surface of the thermoplastic substrate while maintaining the rest of the surface and of the substrate at a substantially lower temperature, then applying to substantially the entire surface of the substrate an unvulcanized layer of the ethylene-propylene polymer, and finally heating the elastomer layer and thermoplastic substrate to the vulcanization temperature of the polymer to vulcanize and/or cross-link same and to unitarily bond the layer and substrate together on the surface at the selected portions thereof but not on the surface between the selected portions. Thereafter the polymer layer and thermoplastic substrate are cured by cooling. A filter plate for a press filter can be made with this method.