Ink composition comprising a conventional flexographic ink stock, a wax, and a chlorinated polyolefin. This ink composition can be used to print webs, e.g. tapes, bearing a low adhesion backsize on one major surface thereof and a pressure-sensitive adhesive on the other major surface thereof.

Dispersions of titanium dioxide pigments with improved long-term resistance to pigment settling and precipitation are disclosed. The pigment dispersions are formed by chemically grafting vinyl and/or acrylic polymers to nitrocellulose in dispersions of nitrocellulose and titanium dioxide pigments. Nitrocellulose forms a loose association with titanium dioxide in dispersion. The chemical grafting improves the precipitation and settling resistance of nitrocellulose, and thus the precipitation and settling resistance of the associated titanium dioxide.

A method of preparing a resin-fortified polymer emulsion is disclosed. In one embodiment, the method comprises polymerizing at least one monomer in the presence of a surfactant, an initiator, a resin and sugar-based vinyl monomer under emulsion polymerization reaction conditions effective for initiating polymerization, wherein an emulsion polymerization product is formed that comprises a sugar-based vinyl monomer. A composition comprising resin-fortified emulsion polymer comprising a sugar-based vinyl monomer, a resin and at least one emulsion polymerizable monomer is also disclosed. An ink comprising a pigment and a resin-fortified polymer emulsion comprising a sugar-based vinyl monomer, a resin and at least one emulsion polymerizable monomer is also disclosed.

A method and apparatus for processing a printing ink containing inhibitors and oligomers in a printing unit of a rotary printing machine in which the drying times of the printing ink on the printing material is shortened and the printing quality improved. In the illustrated embodiments, the printing unit includes two cylinders that form a press nip in which the printing ink is applied to passing printing material, and a catalyst mixture is applied to the printing material either by one of the cylinders or through an applicator device downstream of said press nip. A heating device is located in the conveying direction immediately downstream of the press nip or the applicator device.

Ink composition comprising a conventional flexographic ink stock, a low adhesion backsize compound, and, optionally, a chlorinated polyolefin. This ink composition can be used to print on webs, e.g. tapes, bearing a low adhesion backsize on one major surface thereof and a pressure-sensitive adhesive on the other major surface thereof.