Abstract: A process for producing a high quality di(aryloxy)alkane with a high yield by the use of readily commercially available materials, without using any particular solvent or agent and by means of a simple operation and a general apparatus is provided, which process comprises subjecting a halogenated alkane of the formula (II)X--A--Y (II)wherein X and Y each represent a halogen atom and A represents a lower alkylene group, and a phenol of the formula (III) ##STR1## wherein R.sub.1 to R.sub.5 each are same or different, represent hydrogen, halogen, lower alkyl, lower alkoxy, carboxylic acid salt, acyl or nitro group, and may form a ring in conjunction of two adjacent groups,to condensation reaction in the presence of an alkali in an aqueous medium to form a di(aryloxy)alkane of the formula (I) ##STR2## and is characterized (i) by carrying out the condensation reaction in a molar ratio of the compound of the formula (II): the phenol of the formula (III): the alkali in terms of monovalent base of 1:1.5 to 3.0:1.

Abstract: A heat sensitive recording material comprising a substrate and a recording layer thereon incorporating a colorless or light-colored basic dye and a color acceptor reactive with the dye to form a color when contacted therewith, the recording material being characterized in that, as the color acceptor is used at least one compound selected from the group consisting of 4-hydroxy-4'-isopropyloxydiphenylsulfone, 4,4'-(1,3-dimethylbutylidene) bisphenol, 4,4'-(1-phenylethylidene)bisphenol, 4,4'-(p-phenylenediisopropylidene)bisphenol and 4,4'-(m-phenylenediisopropylidene) bisphenol, and to the recording layer is added at least one of a heat-fusible substance represented by the formula [I] ##STR1## wherein X is hydrogen atom, halogen atom, C.sub.1.about.4 alkyl or C.sub.1.about.4 alkoxy.

Abstract: A cyclic organic phosphorus compound useful as a stabilizer and a fire retardant for organic substances, particularly, high molecular weight compounds is provided, which compound is expressed by the formula (I): ##STR1## and further a process for producing the above compound (I) is provided, which process comprises reacting a compound expressed by the formula (II): ##STR2## with 1,4-benzoquinone.

Abstract: Novel phenolic compounds useful as a color developer suitable for satisfying the quality requirements of heat-sensitive recording materials are provided, which compounds are expressed by the general formula ##STR1## wherein R.sub.1 represents an alkyl group or a cycloalkyl group and R.sub.2 represents hydrogen atom or an alkyl group; and also heat-sensitive recording materials usable in a broad application field are provided, which recording materials are provided with a heat-sensitive recording layer composed mainly of a colorless basic dye and the above compounds as a color developer by which the dye forms colors, overlaid on a substrate.

Abstract: Novel phenolic compounds useful as a color developer suitable for satisfying the quality requirements of heat-sensitive recording materials are provided, which compounds are expressed by the general formula ##STR1## wherein R.sub.1 represents an alkyl group or a cycloalkyl group and R.sub.2 represents hydrogen atom or an alkyl group; and also heat-sensitive recording materials usable in a broad application field are provided, which recording materials are provided with a heat-sensitive recording layer composed mainly of a colorless basic dye and the above compounds as a color developer by which the dye forms colors, overlaid on a substrate.

Abstract: In a heat-sensitive recording material incorporating a colorless or pale-colored basic dye and a color acceptor which is reactive with the basic dye to form a color when contacted therewith, the recording material characterized in that at least one compound represented by the formula [I] is contained in a heat-sensitive recording layer ##STR1## wherein X is --O-- or --COO--, R.sub.1 to R.sub.4 are each hydrogen atom, alkyl having 1 to 8 carbon atoms, aryl having 6 to 10 carbon atoms, aralkyl having 7 to 9 carbon atoms, chlorine atom, acetyl, propionyl, methoxy, methylthio, methoxycarbonyl, cyano, nitro or cyclohexenyl, substituents R.sub.1 and/or R.sub.2 or substituents R.sub.3 and R.sub.4 may link together to form aromatic ring(s), n is an integer of 1 to 10.

Abstract: New phosphorus-containing condensation products are obtained by conducting dehydrocondensation of 10-hydroxymethyl-9, 10-dihydro-9-oxa-10-phosphorphenanthrene-10-oxide compounds with melamine or benzoguanamine.Alternatively, 9, 10-dihydro-9-oxa-10-phosphorphenanthrene-10-oxide compounds with alkoxymethyl melamines or alkoxymethyl benzoguanamines are condensed under heating.These phosphorus-containing condensation products are useful, particularly as a flame retardant for various synthetic resins.

Abstract: In a heat-sensitive recording material incorporating a colorless or pale-colored basic dye and a color acceptor which is reactive with the basic dye to form a color when contacted therewith, the recording material characterized in that at least one compound represented by the formula ?I! is contained in a heat-sensitive recording layer ##STR1## wherein X is --O-- or --COO--, R.sub.1 to R.sub.4 are each hydrogen atom, alkyl having 1 to 8 carbon atoms, aryl having 6 to 10 carbon atoms, aralkyl having 7 to 9 carbon atoms, chlorine atom, acetyl, propionyl, methoxy, methylthio, methoxycarbonyl, cyano, nitro or cyclohexenyl, substituents R.sub.1 and/or R.sub.2 or substituents R.sub.3 and R.sub.4 may link together to form aromatic ring(s), n is an integer of 1 to 10.