Abstract: In a process of producing high purity bis(4-hydroxyphenyl)sulfides which comprises reacting phenols with sulfur dichloride in an organic solvent, the improvement comprising: reacting the phenols with sulfur dichloride in a nonpolar organic solvent; removing partly or wholly the nonpolar organic solvent after the reaction; adding a polar organic solvent to the reaction mixture to dissolve the reaction mixture therein at elevated temperatures; and crystallizing out the high purity bis(4-hydroxyphenyl)sulfides.There is further provided a high performance heat-sensitive recording material which comprises high purity bis(4-hydroxy-3-methylphenyl)sulfide thus prepared and having a melting point in the range of from 123.9.degree. C. to 124.9.degree. C. as a developer and a fluoran compound as a color former.

Abstract: In a process of producing high purity bis(4-hydroxyphenyl) sulfides which comprises reacting phenols with sulfur dichloride in organic solvents, the improvement comprising: reacting the phenols with sulfur dichloride in nonpolar organic solvents; removing partly or wholly the nonpolar organic solvents after the reaction; adding polar organic solvents to the reaction mixture to dissolve the reaction mixture therein at elevated temperatures; and crystallizing out the high purity bis(4-hydroxyphenyl)sulfides.There is further provided a high performance heat-sensitive recording material which comprises high purity bis(4-hydroxy-3-methylphenyl)sulfide thus prepared and having a melting point in the range of from 123.9.degree. C. to 124.9.degree. C. as a developer and a fluoran compound as a color former.

Abstract: A method of producing alkali metal benzenesulfinates having the general formula of ##STR1## wherein M represents Na or K, which comprises: reacting nitrophenylphenyl sulfones having the general formula of ##STR2## wherein n is an integer of 1 or 2, with alkali metal thiophenolates having the general formula of ##STR3## in solvents. The reaction produces also nitrophenylphenyl sulfides as by-products in equimolar amounts to the alkali metal benzenesulfinates, and the oxidation of the sulfides provides the starting nitrophenylphenyl sulfones.A method of producing the nitrophenylphenyl sulfones is also provided wherein the sulfides are oxidized with hydrogen peroxide in the presence both of water-soluble tungstates or molybdates and of phase transfer catalysts in a two-phase heterogeneous solvent.

Abstract: A process for producing polythiobisphenols which comprises: reacting a phenol having the general formula ##STR1## wherein each R independently represents a hydrogen, a halogen or an alkyl, with sulfur monochloride in a polar organic solvent in the presence of a nitrogen-containing organic compound as a catalyst which is selected from the group consisting of tertiary amines, quaternary ammoniums, alkylated acid amides and heteroaromatic compounds, in amounts of about 1-30% by weight based on the amount of the phenol used. As a catalyst, bromine or an alkali metal halide is also usable.A novel process for producing mercaptophenols by the hydrogenolysis of polythiobisphenols in the presence of a nickel catalyst is also disclosed. Raney nickel catalyst which is in advance poisoned with an organosulfur compound in which the sulfur atom has unshared electron pairs is especially effective as a catalyst.

Abstract: A semiconductor device, for example a solar battery cell with a semiconductor element and a composite lead wire attached to the semiconductor element in which the lead wire includes a core and a cover overlying the core. The core has a lower thermal expansion coefficient than that of the semiconductor element, and the cover has a higher thermal expansion coefficient than that of the element and a higher electrical conductivity than that of the core. The lead wire therefore has substantially the same thermal expansion coefficient as that of the semiconductor element.

Abstract: A method of making a solar cell has the following steps: (1) Formation of a surface layer including a dopant on a silicon substrate wherein the surface layer has a higher laser absorption index than the silicon substrate. (2) Irradiation by laser of the surface layer to form a junction in the silicon substrate.