GB769691A - Improvements in and relating to fluorescent compositions - Google Patents

Abstract

Fluorescent coating compositions such as printing pastes and inks, textile and silk screen inks comprise a pigment dyed with a rhodamine dye and 221 dihydroxy-naphthaldazine or one of the fluorescent derivatives thereof, such as those with alkyl or halogen substituted directly in the naphthalene nucleus. The rhodamine and the naphthaldazine are in the ratio by weight of from 1 to 3.0 to 1 to 35. The pigment may be a metal resinate, the preparation and dyeing of which are described in Examples 1-3. In one example, glyceryl phthalate is dispersed in water and dissolved in ammonium hydroxide before being mixed at 55 DEG C. with a dye solution comprising Rhodamine B Extra and Rhodamine 6GDN Extra in methyl glycol and iso-octyl phenyl ether of polyethylene glycol. An aluminium sulphate precipitant solution is added slowly and then an oil-wetting agent, e.g. heptadecenyl imidazoline. Some of the resinate dispersion may be prepared undyed, to be used as an extender. The preparations of letter-press inks, a silk screen ink, a brushing and spraying composition, a paper coating composition and a textile printing composition are described in Examples 4-9. The 2,21 dihydroxy naphthaldazine and the dyed pigment with or without the extender, are mixed with materials such as alkyd printing varnish, paste driers, kerosene, aluminium stearate, metal naphthenate driers, methacrylate resin, naphtha, glycerine, butadiene-styrene, latex anti-foaming agent, pine oil, trisodium phosphate, vinylchloride polymer, melamine formaldehyde resin, cellosolve acetate and dioctyl phthalate in a variety of formul and methods. The yellow fluorescent pigment, 2,21 dihydroxy naphthaldazine is prepared by reacting 2-hydroxy naphthaldehyde with hydrazine sulphate. With pigment ratios of from 1 to 3 to 1 to 30, up to 60 per cent of total pigment may be included in printing inks. The Rhodamine dyed pigments may be made from urea formaldehyde resins, polyvinyl benzal resins, methylene urea and silica in addition to those already mentioned.ALSO:Fluorescent coating compositions such as printing pastes and inks, textile and silk screen inks (see Groups XL (a) and IV (a)) comprise a pigment dyed with a rhodamine dye and 2,21-dihydroxy-naphthaldazine or one of the fluorescent derivatives thereof, such as those with alkyl or halogen substituted directly in the naphthalene nucleus. The rhodamine and the naphthaldazine are in the ratio by weight of from 1 to 3.0 to 1 to 35. The yellow fluorescent pigment 2,21-dihydroxy naphthaldazine is prepared by reacting 2-hydroxy naphthaldehyde with hydrazine sulphate in methanol solution.ALSO:Fluorescent coating compositions such as printing pastes and inks, textile and silk screen inks (see Groups XL(a) and IV(a)) comprise a pigment dyed with a rhodamine dye and 2.21 dihydroxy-naphthaldazine or one of the fluorescent derivatives thereof, such as those with alkyl or halogen substituted directly in the naphthalene nucleus. The rhodamine and the naphthaldazine are in the ratio by weight of from 1 to 3.0 to 1 to 35. The yellow fluorescent pigment 2, 21 dihydroxy naphthaldazine is prepared by reacting 2 - hydroxy naphthaldehyde with hydrazine sulphate in methanol solution.