Abstract: An integral filter leaf assembly comprising microporous polymeric filter cloths heat-bonded to the apices of an undulating screen to form a strong unitary pressure resistant filter unit which essentially replaces filter leaf assemblies. The screen and felt sides of the filter cloths are preferably heat sealable thermoplastics, usually polypropylene to allow heat-bonding and heat-sealing of seams throughout for a unitary assembly strong in compression. Outer filter coat is preferably porous expanded polytetrafluoroethylene. Optionally, a circumferential stiff load-bearing frame may be enclosed within the assembly.

Abstract: This invention provides a filter cloth assembly for use on a filter plate of a center-feed filter press, which comprises a two-part filter cloth with fittings for rapid and easy assembly on the filter plate, one cloth on each side. Methods of manufacture of the novel assembly and its parts and a new method for bonding otherwise incompatible plastics and elastomers are disclosed.