GB816750A - Process for treating materials which are sensitive to ultra-violet rays - Google Patents

Abstract

Colourless compounds which exhibit no blue or at most a weakly blue fluorescence and which contain one or more 1 : 3 : 4-oxdiazole or 1 : 3 : 4-thiadiazole rings and at least one aromatic nucleus bound directly to the heterocyclic ring are used to absorb light in the ultra-violet region. The compounds may have the general formula <FORM:0816750/III/1> in which X is oxygen or sulphur and R and R1 are phenyl residues which may be substituted with hydroxyl, alkyl, alkoxy, carboxy, carboxyalkyl, sulphonic acid, or sulphonamide groups, halogen atoms or fused-on rings. The compounds may be included in oils, including skin oils giving protection against the sun, and fats.ALSO:Colourless compounds which exhibit no blue or at most a weakly blue fluorescence and which contain one or more 1 : 3 : 4-oxidiazole or 1 : 3 : 4-thiadiazole rings and at least one aromatic nucleus bound directly to the heterocyclic ring are used to absorb light in the ultra-violet region. The compounds may have the general formula <FORM:0816750/IV (a)/1> in which X is oxygen or sulphur and R and R1 are phenyl residues which may be substituted with hydroxyl, alkyl, alkoxy, carboxy, carboxyalkyl, sulphonic acid, or sulphonamide groups, halogen atoms or fused-on rings. The compounds may be applied in aqueous or organic solution or dispersion to fibres, threads, yarns, woven or knitted fabrics, felts, feathers, hair, pelts, skins, leather, straw, wood, wood pulp, paper, wrapping paper, cardboard, compressed wood or articles made therefrom or films or foils. The compounds may be included in lacquers, gelatine, starch, natural or synthetic rubber, transparent and other artificial resins (e.g. polyamides, polyesters, polyvinyl chloride or polyvinyl alcohol), photographic emulsions and films or papers prepared therewith, oils, including skin oils giving protection against the sun, fats, flour and sugar, solutions for spinning fibres or films from viscose, linear synthetic polyamides or cellulose acetate and in polyvinyl chloride masses. In examples: (1) a film is produced from a solution of cellulose acetate in acetone containing 2 : 5-bis-[21-methoxyphenyl - (1)1] - 1 : 3 : 4 - oxdiazole. (3) A stabilized mixture of polyvinyl chloride and dioctyl phthalate incorporating 2 : 5-bis-[21-hydroxyphenyl - (11) - 1 : 3 : 4 - oxdiazole is gelatinized at 150 DEG C. on a calender to produce a foil. (4) A film is produced from an aqueous solution of polyvinyl alcohol containing 2 : 5-bis-[sulpho - 21 - hydroxyphenyl - (11)] - 1 : 3 : 4 - oxdiazole.ALSO:Compounds of the general formula <FORM:0816750/IV (b)/1> where X is oxygen or sulphur and R and R1 are phenyl residues which may be substituted with hydroxyl, alkyl, alkoxy, carboxy, carboxyalkyl, sulphonic acid, or sulphonamide groups, halogen atoms or fused-on rings are prepared by the action of an agent capable of eliminating water, but not of reacting with phenolic hydroxyl groups under the conditions of the reaction, upon a dihydrazide of the general formula RCONHNHCOR1 or by converting into hydroxyl groups substituents convertible into such groups in the oxdiazole compounds (see Specification 816,749, [Group IV (a)]). In examples: (1) N:N-di-[2-methoxy-benzoyl] hydrazine is reacted with thionyl chloride to give <FORM:0816750/IV (b)/2> and di-(2:4-dihydroxyphenyl); the diphenyl, di-p-tolyl, di-p-methoxyphenyl, di-o-hydroxyphenyl anologues are prepared in a similar manner; (2) N:N1-dibenzoyl-hydrazine is reacted with phosphorus pentasulphide to give the compound <FORM:0816750/IV (b)/3> The di-p-tolyl analogue is prepared in a similar manner; (3) 2 - oxynaphthalene - 3 - carboxylic acid hydrazide is heated with 2-oxynaphthalene-3-carboxylic acid chloride to give <FORM:0816750/IV (b)/4> which is treated with dry nitrobenzene and aluminium chloride with the evolution of hydrogen chloride to yield 2:5-bis-[21-hydroxynaphthyl-(31)]-1:3:4-oxdiazole; (4) the compound <FORM:0816750/IV (b)/5> is obtained by reacting hydrazine sulphate with salicylic acid in oleum, the condensation product being neutralized with sodium carbonate. Other analogues are obtained using 4-hydroxybenzoic acid, 2:4-dihydroxy-benzoic acid or 4-methyl-2-hydroxybenzoic acid instead of the salicylic acid. A clear colourless film which absorbs the greater part of ultra-violet light of long wavelength is produced by adding the disodium salt of 2.5-bis-[sulpho-21-hydroxyphenyl-(11)] 1.3.4-oxdiazole to an aqueous 10 per cent gelatin solution.ALSO:Colourless compounds which exhibit no blue or at most a weakly blue fluorescence and which contain one or more 1 : 3 : 4-oxdiazole or 1 : 3 : 4-thiadiazole rings and at least one aromatic nucleus bound directly to the heterocyclic ring are used to absorb light in the ultra-violet region. The compounds may have the general formula <FORM:0816750/IV (c)/1> in which X is oxygen or sulphur and R and R1 are phenyl residues which may be substituted with hydroxyl, alkyl, alkoxy, carboxy, carboxyalkyl, sulphonic acid or sulphonamide groups, halogen atoms or fused-on rings. The compounds may be applied in aqueous or organic solution or dispersion to fibres, threads, yarns, woven or knitted fabrics or felts composed of wool, silk, cotton, hemp, flax, linen, jute, ramie, regenerated cellulose, polyesters or polyamides, or to hair.ALSO:Colourless compounds which exhibit no blue, or at most a weakly blue, fluorescence and which contain one or more 1 : 3 : 4-oxidiazole or 1 : 3 : 4-thiadiazole rings and at least one aromatic nucleus bound directly to the heterocyclic ring are used to absorb light in the ultra-violet region. The compounds may have the general formula <FORM:0816750/VI/1> in which X is oxygen or sulphur and R and R1 are phenyl residues which may be substituted with hydroxyl, alkyl, alkoxy, carboxy, carboxyalkyl, sulphonic acid or sulphonamide groups, halogen atoms or fused-on rings. The compounds may be applied in aqueous or organic solvent solution or dispersion to fibres, threads, woven or knitted fabrics or felts of wool, silk, cotton, hemp, flax, linen, jute and ramie, to feathers, hair, pelts, skins and natural-tanned and chemical-tanned leathers, and to wrapping papers, films and foils. The compounds may be included in gelatine, starch, food fats and oils, flour and sugar, and in oils which protect against the sun.