Patent GB-957438-A (GB)
Title: Substituted 2-phenyl benzoxazoles and benzothiazoles and ink formulations containing them
IPC: C09D11/00
Filed: 1960-11-14
Abstract: The invention comprises compounds of the formula: <FORM:0957438/C2/1> where X is O or S, Y is -NHCO- or -NHCONH- and Z1 is hydrogen, a substituted or unsubstituted aliphatic group having 1-8 carbon atoms in a saturated carbon chain, or a radical -(CR1R2)n R3, where n is 0 or 1, R1 is hydrogen or an aromatic group having not more than two benzene nuclei, R2 is hydrogen, an aliphatic group having 1-7 carbon atoms in a saturated carbon chain, or an aromatic group having not more than two benzene nuclei, and R3 is an aromatic group having not more than two benzene nuclei.  Z1 and R2 when aliphatic groups may be substituted by chloro, sulpho, hydroxy, methoxy or phenoxy, but are preferably alkyl groups.  R1, R2 and R3 when aromatic may be a phenyl, diphenyl or naphthyl group, and may be substituted, e.g. by chloro, sulpho, hydroxy, methyl, chloromethyl, methoxy and phenoxy groups. Many compounds of the formula given are specified.  They may be prepared by reacting o-aminophenol or o-aminothiophenol with 5-nitrosalicyl aldehyde, oxidizing the resulting Schiff's base with lead tetraacetate to 2-(21-hydroxy-51-nitrophenyl) benzoxazole or benzothiazole, reducing the nitro group to amino, and finally reacting with an appropriate acid anhydride, acid halide or isocyanate.  The compounds of the invention are colourless but fluoresce in ultra-violet light, and are used in ink formulations for marking materials.ALSO:Ink formulations comprise a normally colourless organic compound which fluoresces in ultraviolet light as defined below, together with a solvent and an organic binder; suitable binders are gums, cumarone-indene resins, modified resins such as condensation products of resin or terpene hydrocarbons with unsaturated polybasic acids, alkyd resins, urea-formaldehyde resins and cellulose ethers and esters, such as methyl, ethyl and benzyl cellulose and cellulose acetate, acetobutyrate and acetopropionate. The fluorescent compound is of formula: <FORM:0957438/C3/1> where X is O or S, Y is -NHCO- or -NHCONH-, and Z1 is hydrogen, a substituted or unsubstituted aliphatic group having 1-8 carbon atoms in a saturated carbon chain, or a radical -(CR1R2)n R3, where n is 0 or 1, R1 is hydrogen or an aromatic group having not more than two benzene nuclei, R2 is hydrogen, an aliphatic group having 1-7 carbon atoms in a saturated carbon chain, or an aromatic group having not more than two benzene nuclei, and R3 is an aromatic group having not more than two benzene nuclei (see Division C2). Suitable solvents are hydrocarbons such as naphthas, alcohols such as ethanol, ethers such as n-propyl ethyl ether, glycols such as propylene glycol and diethylene glycol, and glycol ethers such as ethylene glycol monobutyl ether and bis-[2-(21-methoxyethoxy)ethyl] ether. Specified compositions contain the fluorescent compound together with bis-[2-(21-methoxyethoxy)ethyl] ether, triethyl phosphate, cellulose acetate and silica.ALSO:Ink formulations comprise a normally colourless organic compound which fluoresces in ultra-violet light as defined below, together with linseed oil or tung oil, or with a gum and an organic solvent.  The fluorescent compound is of formula <FORM:0957438/C3/1> where X is O or S, Y is -NHCO- or -NHCONH-, and Z1 is hydrogen, a substituted or unsubstituted aliphatic group having 1-8 carbon atoms in a saturated carbon chain, or a radical -(CR1R2)nR3, where n is 0 or 1, R1 is hydrogen or an aromatic group having not more than two benzene nuclei, R2 is hydrogen, an aliphatic group having 1-7 carbon atoms in a saturated carbon chain, or an aromatic group having not more than two benzene nuclei, and R3 is an aromatic group having not more than two benzene nuclei (see Division C2).  Suitable solvents are hydrocarbons such as naphthas, alcohols such as ethanol, ethers such as n-propyl ethyl ether, glycols such as propylene glycol and diethylene glycol, and glycol ethers such as ethylene glycol monobutyl ether and bis-[2-(21-methoxyethoxy) ethyl] ether.ALSO:Textiles are marked for identification with an ink formulation comprising an organic binder, an organic solvent and a normally colourless compound which fluoresces under ultra-violet light of the formula <FORM:0957438/D1-D2/1> where X is 0 or S, Y is -NHCO- or NHCONH-, and Z1 is hydrogen, a substituted or unsubstituted aliphatic group having 1-8 carbon atoms in a saturated carbon chain, or a radical -(CR1 R2)n R3, where n is 0 or 1, R1 is hydrogen or an aromatic group having not more than two benzene nuclei, R2 is hydrogen, an aliphatic group having 1-7 carbon atoms in a saturated carbon chain, or an aromatic group having not more than two benzene nuclei, and R3 is an aromatic group having not more than two benzene nuclei (see Division C2).  Suitable organic binders are gums, resins and cellulose ethers and esters (see Division C3).  Preferably the solvent is water-soluble, so that on treating the wet print with water the solvent is removed.  The resulting print is invisible under normal conditions but fluoresces in ultra-violet light; it is stable to laundering.