Patent GB-944265-A (GB)
Title: Naphthotriazole brightening agents
IPC: D06P1/642
Filed: 1962-02-28
Abstract: The invention comprises fluorescent naphthotriazoles of the formula: <FORM:0944265/C2/1> wherein R1 and R2 represent hydrogen, halogen such as fluorine, chlorine and bromine, C1-4 alkyl, C1-6 alkoxy or cycloalkoxy, and R3 represents alkyl, monohydroxyalkyl, dihydroxyalkyl, trihydroxyalkyl, dialkylaminoalkyl, aryl (optionally substituted by chlorine, bromine, fluorine, alkyl or alkoxy), hexamethyleneiminoN-ethyl or morpholino-N-alkyl or piperidino-N-alkyl in which the alkyl group contains from 1 to 4 carbon atoms.  The naphthotriazoles may be prepared by diazotizing a stilbene of the formula: <FORM:0944265/C2/2> coupling the product with 2-naphthylamine, oxidizing the resulting monazo dye to a triazole, converting the free carboxylic group to an acid chloride group by treatment with thionyl chloride and finally reacting the acid chloride group with an appropriate phenol, dialkylamino-alkanol, heterocyclic-substituted alkanol or mono-, di-, tri-, or tetra-hydric alcohol.  Alternatively, compounds of the formula: <FORM:0944265/C2/3> may be formed from the free carboxylic acid via the acid chloride, the nitro group in the resulting ester reduced to an amino group, the resulting compound diazotized, coupled with 2-naphthylamine and finally oxidized to the required triazole.ALSO:Polyethylene terephthalate is brightened by adding to the starting mixture of dimethyl terephthalate and ethylene glycol, or to a low polymer obtained therefrom, a fluorescent naphthotriazole of the formula: <FORM:0944265/C3/1> wherein R1 and R2 represent hydrogen, halogen such as fluorine, chlorine and bromine, C1-4 alkyl, C1-6 alkoxy or cycloalkoxy, and R3 represents alkyl, monohydroxyalkyl, dihydroxyalkyl, trihydroxyalkyl, dialkylaminoalkyl, aryl (optionally substituted by chlorine, bromine, fluorine, alkyl or alkoxy), hexamethyleneimino-N-ethyl or morpholino-N-alkyl or piperidino-N-alkyl in which the alkyl group contains from 1 to 4 carbon atoms.ALSO:Monazo dyestuffs are prepared by diazotizing a stilbene of the formula <FORM:0944265/C3/1> wherein R1 and R2 represent hydrogen, halogen such as fluorine, chlorine and bromine, C1-4 alkyl, C1-6 alkoxy or cycloalkoxy, and coupling the product with 2-naphthylamine.  Alternatively, further monazo dyestuffs are formed by reducing the nitro group in compounds of the formula <FORM:0944265/C3/2> wherein R3 represents alkyl, monohydroxyalkyl, dihydroxyalkyl, trihydroxyalkyl, dialkylaminoalkyl, aryl (optionally substituted by chlorine, bromine, fluorine, alkyl or alkoxy), hexamethyleneimino - N - ethyl or morpholinoN-alkyl or piperidino - N - alkyl in which the alkyl group contains from 1 to 4 carbon atoms, diazotizing the resulting amino compound and coupling it with 2-naphthylamine.ALSO:Nylon, polyethylene teraphthalate and polyacrylonitrile in the form of films, fibres and fabrics are brightened by treatment with a fluorescent naphthotriazole of the formula:-  <FORM:0944265/D1-D2/1> wherein R1 and R2 represent hydrogen, halogen such as fluorine, chlorine and bromine, C1-4 alkyl, C1-6 alkoxy or cycloalkoxy, and R3 represents alkyl, monohydroxyalkyl, dihydroxyalkyl, trihydroxyalkyl, dialkylaminoalkyl, aryl (optionally substituted by chlorine, bromine, fluorine, alkyl or alkoxy), hexamethyleneimino-N-ethyl or morpholino-N-alkyl or piperidino-N-alkyl in which the alkyl group contains from 1 to 4 carbon atoms.  The fluorescent naphthotriazoles may be applied to the materials to be brightened from a dimethylformamide solution to which has been added a small amount of an aqueous polyoxyethylene surfactant.