Patent GB-716458-A (GB)
Title: Improved pigment dispersion and method for dispersing pigments in mineral oil printing inks
IPC: C09D11/02
Filed: 1952-05-27
Abstract: In a pigmented mineral oil ink in which the pigment is associated with an amount of a succinate sufficient at least to form a monomolecular film covering the pigment particles, the succinate being a sulphosuccinate of the general formula <FORM:0716458/IV (a)/1> in which Me is an alkali or alkaline earth metal, R1 and R2 are selected from alkyl and the residue of incompletely esterified glycerine, R1 + R2 containing at least 18 carbon atoms, or a thiophosphato-succinate of the general formula <FORM:0716458/IV (a)/2> in which Me has the meaning given above, n is the valency of Me, R1, R2 and R3 are alkyl radicals, and R1 + R2 + R3 contains at least 18 carbon atoms, the vehicle may consist of 49 per cent. of a modified phenolic resin (example 23), more particularly a rosin-modified phenol-formaldehyde resin (example 28), and 51 per cent. of a high boiling paraffin hydrocarbon.  Many succinates and inorganic and organic pigments are given.ALSO:Sulpho- and dithiophosphato-succinates of the respective general formul : <FORM:0716458/IV (b)/1> (I) <FORM:0716458/IV (b)/2> (II) wherein in I R1 and R2 are alkyl radicals or residues of incompletely esterified glycerine and R1 + R2 has at least 18 carbon atoms, and in II R1, R2 and R3 are alkyl radicals, R1 + R2 + R3 has at least 18 carbon atoms, Me is an alkali or alkaline earth metal, and n is the valency of Me, are used for coating or associating with pigments in making mineral oil printing inks.  In examples, in preparing the sulphosuccinates, (1) 7-ethyl-2-methyl-4-undecyl alcohol is esterified with maleic acid to form the monoester and heated with sulphuric acid and further alcohol to form the diester, alcohol being removed by vacuum distillation; the ester is then transformed into the sulphosuccinate by reaction in aqueous media with sodium bisulphite; (2) the fumaric diester of 5 - ethyl - 2 - nonyl alcohol is prepared and transformed into the sulphosuccinate by reaction with sodium bisulphite in aqueous media.  The following sulphosuccinates are prepared by the process of example 1 or 2: bis(2,6,8-trimethyl - 4 - nonyl) -, bis(2,8 - dimethyl - 6 - isobutyl - 4 - nonyl) -, bis(3,5,5 - trimethylhexyl)-, bis(tridecyl) -, bis(2 - butyl octyl)-, bis mixed (2 - butylhexyl)(2 - ethyl octyl) -, bis(n - decyl)-, bis(n - dodecyl) -, bis(hexadecyl) - and bis (octadecyl) - sodium sulphosuccinates; monooctadecyl - and 5,7,7 - trimethyl - 2(11,31,31-trimethylbutyl) - octyl - disodium sulphosuccinates are made by forming the monomaleates of the alcohols and sulphonating with sodium sulphite instead of the bisulphite.  No preparation is given of the following compounds: sodium sulphosuccinate of diglyceride of stearic acid, polysulphosuccinate of monoglyceride of stearic acid sodium salts; bis(3-octadecanoyl oxy - 2 - hydroxy - propyl) -, di(4 - amyl cyclohexyl) -, di(4 - secondary butyl C4) -, bis[(1,3 - diocta decanoyl oxy)2 - propyl] -, and bis oleylsodium sulphosuccinates; bis-tridecyl barium sulphosuccinate, bis(7-ethyl-2-methyl4 - undecyl) - calcium sulphosuccinate; barium salts of dihexyldithiophosphato - 3,3,5-trimethylhexyl -, dihexyldithiophosphato - tridecyl -, and dihexyldithiophosphato - octadecyl - succinates, and sodium salt of 3,5,5-trimethyl hexyl di-secondary butyl dithiophosphato succinate.ALSO:In a pigmented mineral oil ink, the pigment is associated with an amount of a substituted succinate at least to form a monomolecular film covering the pigment particles, the succinate being a sulpho-succinate of the general formula:- <FORM:0716458/III/1> in which Me is an alkali or alkaline earth metal, and R1 and R2 are selected from alkyl and the residue of incompletely esterified glycerine, R1+R2 containing at least 18 carbon atoms, or a thiophosphatosuccinate of the general formula:- <FORM:0716458/III/2> in which R1, R2 and R3 are alkyl radicals, R1+R2+R3 having at least 18 carbon atoms, Me is an alkali or alkaline earth metal and n is the valency of Me.  The succinate is associated with the pigment by (1) introducing the succinate into the ink during its preparation, (2) making a slurry of the pigment in an aqueous medium with the succinate, recovering the coated pigment and drying it, (3) mixing the succinate with the pigment to form a press cake and adding mineral oil, or by (4) p  adding the succinate to the oil or ink vehicle.  Many examples of succinates are given.  Among the more important pigments that may be used are-alkali blue, phloxine toner, barium lithol red, peacock blue, chrome yellow, chrome green, iron blues and titania. Benzidine yellows do not respond favourably to the treatment.