GB760335A - Production of inhibitors - Google Patents

Abstract

A stable aqueous paste of a substantially water-insoluble solid organic compound is obtained by adding to a dispersion of the said compound, in an aqueous medium containing a water-soluble dispersing agent, a water-soluble salt of a character and in quantity sufficient to salt out the dispersing agent and so cause gelling of the dispersion, the salt being one which does not form a water-insoluble product by reaction with the dispersing agent. Suitable dispersing agents are, for example, sodium lignosulphonate, other lignosulphonate salts, lignosulphonic acid and water-soluble soaps of higher fatty acids. Suitable water-soluble salts for the salting-out are, for example, sodium chloride, potassium chloride, sodium sulphate and sodium phosphate, Na3PO4. The process is applied to the formation of stable pastes of the 1,3-diazacyclo alkyl compounds of general formula <FORM:0760335/IV(b)/1> in which R is hydrogen, alkyl or aryl, R1 is cycloalkyl, aralkyl or aryl and n is an integer of at least 2. They are made by reacting an aldhyde RCHO with a compound of formula R1NH(CH2)nNHR1 in water containing a water soluble dispersing agent and treating the soformed dispersion with a water-soluble salt. In the above formula R may be, for example, methyl, ethyl, propyl, butyl, isobutyl, amyl, phenyl or tolyl and R1 may be cyclohexyl, benzyl, phenyl, tolyl, ethylphenyl, chlorophenyl, methoxyphenyl, alkoxy phenyl or acetaminophenyl and the R1 radicals may be the same or different. The process may also be used for the production of pastes of other compounds, e.g. 2,4 - dinitro - diphenylamine (prepared from 2,4-dinitrochlorbenzene and aniline); 2,4-dinitro - 41 - amino - diphenylamine (prepared from 2,4-dinitro-chlor-benzene and p-phenylenediamine) and 2 - nitro - 41 - chlordiphenylamine (prepared from 2-nitrochlorbenzene and p-chloraniline). In the example, sodium lignosulphonate is added to a mixture of formalin and N,N1 - diphenyl - ethylenediamine; after the reaction is complete additional sodium lignosulphonate is added to the 1,3-diphenyl-imidazolidine so formed; the resulting dispersion is ball-milled and sodium chloride is added to produce a stable gelatinous paste. Specifications 664,204 and 665,667 are referred to.ALSO:A stable aqueous paste of a substantially water-insoluble solid organic compound (e.g. a dyestuff suitable for direct dyeing of cellulose acetate textiles, or a 1.3-diazacyclic compound such as 1.3 - diphenyl imidazolidine) is obtained by adding to a dispersion of the compound in a aqueous medium containing a water-soluble dispersing agent, a water-soluble salt sufficient in quantity to salt out the dispersing agent and so cause gelling of the dispersion, the salt being one of which does not form a water-insoluble compound by reaction with the dispersing agent. In an example a cellulose acetate fabric is dyed in a bath containing the blue dye, 1-(b -hydroxyethylamino)-4-methylamino anthaquinone, turkey red oil, green soap, potassium pyrophosphate and a gelatinous paste of 1.3-diphenylimidazolidine dissolved in hot water. The gelatinous paste is obtained by treating a dispersion of 1.3-diphenyl-imidzolidine in an aqueous medium containing sodium lignosulphonate, with sodium chloride. Specifications 664,204 and 665,667 [Group IV(b)] are referred to.