Abstract: A multilayer printed wiring board which comprises B layer laminated on one or both faces of A layer, wherein A layer is a layer constituted with one or more layers which comprise a resin composition comprising at least one resin selected from epoxy resins, phenolic resins, unsaturated polyester resins and polyimide resins of a bismaleimide type and B layer is a layer constituted with one or more layers which comprise a resin composition comprising 40% by weight or more of a styrenic resin having a syndiotactic configuration.

Abstract: Provided by the present invention is a mold release film for sealing a semiconductor element, which does not deform or cause deformation of the terminals of the semiconductor and which has good releasability during the semiconductor element sealing process, and a sealing method for a semiconductor element using the mold release film, which can improve efficiency of manufacturing a semiconductor.

Abstract: There are disclosed a method for using a molding which comprises using a molding produced by thermoforming a sheet for thermoforming comprising a styrenic polymer having a high degree of syndiotactic configuration or a composition thereof in an atmosphere containing a chlorofluorohydrocarbon and also a method for using a molding which comprises using a molding produced by thermoforming a laminate comprising at least one surface layer of the above styrenic polymer or a composition thereof and an other layer of a thermoplastic resin or a composition thereof in an atmosphere the same as above-mentioned.The moldings to be employed in the present invention are excellent in chemical resistance, solvent resistance and resistance against CFC and HCFC, and the sheet for thermoforming and the laminate are useful as the starting raw materials for the aforesaid molding.

Abstract: The present invention provides a method of recovering a lithium chloride, which comprises reacting a dihalogenated aromatic compound and an alkali metal sulfide and/or alkali metal hydrogen sulfide in a polar solvent under the pressure of lithium chloride, separating a solvent insoluble component from the resultant reaction mixture to obtain a solution, and calcinating a residue obtained by removing volatile substances from the resultant solution, as well as a method of recovering a lithium chloride, which comprises reacting a dihalogenated aromatic compound and an alkali metal sulfide and/or alkali metal hydrogen sulfide in a polar solvent under the pressure of lithium chloride, separating the granular polymer ingredient from the resultant reaction mixture subjecting the liquid suspension obtained by said separation to solid-liquid separation and calcinating the residue obtained by removing volatile substances from the resultant solution component.

Abstract: Disclosed is a process for producing stably a polyarylene sulfide of high purity and high molecular weight by contacting a dihalogeno aromatic compound with an alkali metal sulfide in a polar solvent which comprises, as a first stage, reacting a dihalogeno aromatic compound with an alkali metal sulfide in a polar solvent in the presence of a lithium compound and in the presence of substantially no water at 200.degree.-270.degree. C. with concentration of remaining alkali metal sulfide being 5.5 g/l-polar solvent or less in terms of sulfur; then adding water in an amount of 1.0-10 mols per 1 mol of said alkali metal sulfide; and, thereafter, as a second stage, carrying out the reaction at 220.degree.-280.degree. C. Preferred dihalogeno aromatic compound is p-dichlorobenzene, preferred alkali metal sulfide is sodium sulfide and/or lithium sulfide and preferred lithium compound is lithium chloride and/or lithium sulfide.

Abstract: Disclosed is a method for producing a polyarylene sulfide comprising contacting a dihalogenated aromatic compound with an alkali metal sulfide in a polar solvent, wherein a halogenated aromatic compound containing active hydrogen is present in the reaction system.