Abstract: A composite semipermeable membrane and a process for preparation thereof are described, wherein said membrane comprises (1) a porous substrate, (2) an ultrathin film as a surface layer formed by polymerization by crosslinking of polyvinyl alcohol and an amino compound having at least two secondary amino groups using a polyfunctional crosslinking reagent capable of reacting with secondary amino groups and hydroxyl groups, and (3) a porous inner layer composed of water insoluble polyvinyl alcohol which is present between the porous substrate and the ultrathin film.

Abstract: A composite semipermeable membrane is described, wherein said membrane comprises (1) a porous substrate, (2) an ultrathin film as a surface layer formed by polymerization by crosslinking of polyvinyl alcohol and an amino compound having at least two secondary amino groups using a polyfunctional crosslinking reagent capable of reacting with secondary amino groups and hydroxyl groups, and (3) a porous inner layer composed of water insoluble polyvinyl alcohol which is present between the porous substrate and the ultrathin film.

Abstract: A composite semipermeable membrane which comprises a porous substrate and an ultrathin dense layer having solute removal performance formed on said substrate by polymerization by crosslinking of a reactive material composed of at least one material selected from the group consisting of(a) a mixture of triazine represented by the general formula: ##STR1## (wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 each represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), and polyamine monomer,(b) said triazine modified with amine,(c) a mixture of said triazine modified with amine, and polyamine monomer,(d) a oligomer composed of said triazine and polyamine monomer, and(e) a mixture of an oligomer composed of said triazine and polyamine monomer, and polyamine monomer,as a main component, with a polyfunctional crosslinking reagent having two or more functional groups capable of reacting with amino groups in the molecule, and a process for preparing the same.

Abstract: A method for easily providing a spiral type-fluid separation module by horizontally rotating a mandrel around its axis from which one or more layer arrangements consisting of a plurality of layer elements hang downward, and winding the layer arrangements about the mandrel without occurance of non-uniform shifting and wrinkles in the layer elements, while applying tension to at least one layer element by means of a tension system.

Abstract: This invention provides a process for producing a heat resistant metallic laminated sheet which is composed of mutually insulated outer metallic sheets or foils and an inner binder layer sandwiched therebetween.In this process, the binder layer is a film of a heat resistant heterocyclic polymer from which volatile matter is substantially removed. The sandwiched structure composed of the outer metallic sheets and the binder film put therebetween is bonded at a temperature range above the heat distortion temperature of the binder film to form the metallic laminated sheet.

Abstract: A metal laminate having high thermal stability is produced by forming a cured film layer of a thermally stable heterocyclic polymer such as polyamide imide having only a small volatile content on at least one surface of one or both of metal plates or foils such as aluminum, separately forming an adhesive layer of a thermally stable heterocyclic polymer having a thickness of one-third or less of the above film layer and containing a volatile matter in an amount of not more than 20% by weight, and then heat bonding both of the metal plates or foils through the above adhesive layer with the film layer being allowed to face the adhesive layer. The metal plates and foils are mutually insulated.