Abstract: The invention comprises an adhesion promoter for a printing ink and a printing ink comprising the adhesion promoter. The adhesion promoter comprises the product of reacting together (a) a solution of a polymer or synthetic resin (b) a sulphonic acid or a derivative of a sulphonic acid, and (c) a metal compound selected from one or more of the group consisting of a metal halide, metal alkoxide, metal halo-alkoxide or a condensed metal alkoxide, wherein the metal is selected from titanium or zirconium.

Abstract: The invention provides a method of carrying out a Lewis-acid catalysed organic reaction in the presence of a Lewis acid catalyst comprising a metal-organic compound having the following formula: M(HO(CR1R2)z)a(O(CR1R2)z)bY—(CR3R4)?-Y((CR1R2)zO)c((CR1R2)zOH)d.nR5OH (Formula I) in which: M is a metal atom, preferably titanium, zirconium, hafnium or iron (III) Y is selected from P and N, but Ss very preferably N; each R1, R2, R3 and R4 is independently selected from H, alkyl, aryl, substituted alkyl or substituted aryl, R5 is hydrogen, an alkyl group, a hydroxy-functionalised alkyl group, a polyoxyalkylmoiety, R6O or R7COO where R6 and R7 may each represent H, alkyl, aryl or alkyl-aryl; d and a are each O or 1, b and c are each 1 or 2, b+c=the valency of M, a+b+c+d=4, each z is independently 1, 2, 3 or 4; x represents the least number of C atoms between the Y atoms and is 2 or 3 and n is a number in the range from 0 to 4.

Abstract: The invention comprises an adhesion promoter for a printing ink and a printing ink comprising the adhesion promoter. The adhesion promoter comprises the product of reacting together (a) a solution of a polymer or synthetic resin (b) a sulphonic acid or a derivative of a sulphonic acid, and (c) a metal compound selected from one or more of the group consisting of a metal halide, metal alkoxide, metal halo-alkoxide or a condensed metal alkoxide, wherein the metal is selected from titanium or zirconium.

Abstract: The invention comprises an adhesion promoter for a printing ink and a printing ink comprising the adhesion promoter. The adhesion promoter comprises the product of (a) mixing together a solution of a polymer or synthetic resin with an organophosphorus compound, and then (b) mixing the mixture formed in (a) with a titanium compound selected from a titanium halide, alkoxide, halo-alkoxide or a condensed titanium alkoxide or a mixture of more than one of these titanium compounds.

Abstract: The invention comprises an adhesion promoter for a printing ink and a printing ink comprising the adhesion promoter. The adhesion promoter comprises the product of (a) mixing together a solution of a polymer or synthetic resin with an organophosphorus compound, and then (b) mixing the mixture formed in (a) with a titanium compound selected from a titanium halide, alkoxide, halo-alkoxide or a condensed titanium alkoxide or a mixture of more than one of these titanium compounds.

Abstract: A printing ink for radiation curing, e.g. by UV radiation or an electron beam, comprises a mixture of a polymerizable composition, a pigment or a dye and a titanium or zirconium compound which is an alkoxide of an unsaturated alcohol, said polymerizable composition comprising at least one unsaturated monomer and, optionally, at least one prepolymer and being polymerizable by exposure to radiation. The titanium or zirconium compound acts as an adhesion promoter for the ink.

Abstract: A printing ink comprises a polymeric binder, a solvent and an adhesion promoting agent which is the reaction product of a zirconium orthoester and ethyl acetoacetate in which the molar ratio of zirconium to ethyl acetoacetate is from 1:1 to 1:4. Preferably, the inks are based on nitrocellulose or an ester type modified cellulose. The inks have been found to have adhesion and heat stability properties similar to inks containing titanium acetylacetonate but the zirconium additives have a much reduced tendency to discolor the ink.