Abstract: Disclosed is a heat-sensitive recording material useful, for example, in the manufacture of labels used in connection with the sale of meat, produce, and the like. The material comprises a cellulosic or other suitable substrate, a thermally imprintable color producing layer and a water-insoluble protective layer over the color-producing layer. It may also include a second protective layer and/or a pressure-sensitive adhesive layer on the opposite side of the substrate from the color-producing layer, and a releasable liner covering the adhesive layer. The color-producing layer has a colorless or pale leuco dye, an acidic developer for producing upon imagewise heating of the recording material, a water-soluble, polymeric binder material, and a basic, acid-neutralizing agent for reducing background discoloration.

Abstract: Disclosed is a recording sheet comprising a support having a layer of color developer capable of reacting with oil-soluble, basic, chromogenic dyes to produce rapidly a mark of improved color intensity and improved fade resistance. In addition to the conventionally used constituents such as binders, whitening agents, and fillers, the coating comprises (a) a phenol-formaldehyde condensate oligomer mixture, (b) an aromatic carboxylic acid, and (c) an inorganic magnesium compound, preferably magnesium oxide or magnesium hydroxide. Best results are obtained when components a, b, and c are present at ratios of 50 parts oligomer, 1.0-2.5 parts acid, and 10-40 parts magnesium compound.

Abstract: Disclosed is a thermally stable liquid negative developer comprising an organic liquid carrier, a pigment, a stabilizing gel on the borderline of solubility in the carrier, a latex which imparts a fixative function to the developer, and a two component charge control agent. The charge control agent consists of a first polymer, soluble in the carrier, having a basic character because of the inclusion of pyrrolidone or hydroxylated alkyl groups, and a second polymer, insoluble or on the borderline of solubility in the carrier, having an acid character because of the inclusion of free halogenated groups, and containing a minor amount of carrier soluble moieties. The two components may constitute separate ingredients, or either or both components may be incorporated into the structure of other developer components. Thus, the basic component may be included in the gel, and the acid component included in the latex.

Abstract: Disclosed is a developer composition which has improved depletion characteristics. The developer comprises an organic carrier containing latex particles comprising a major amount of a C.sub.1 -C.sub.6 lower alkyl acrylate or methacrylate polymer, a pigment system, a charge control agent consisting of a copolymer of C.sub.2 -C.sub.6 lower alkyl vinyl ether and a vinyl chloride, and an acrylic polymer gel for stabilizing the dispersion. The developer may be used in conventional copying equipment to make greater than about 20,000 copies of acceptable image density.

Abstract: Disclosed is a developer composition which in use exhibits improved depletion characteristics and produces copies of high image density. The developer comprises an organic carrier containing a pigment system, a charge control agent, and a "gelatex" which acts as a fixitive and a dispersant. The gelatex comprises a carrier-insoluble vinyl polymer and a multiply-branched, vinyl polymer which physically entraps or entangles the carrier-insoluble polymer and is on the borderline of solubility in the carrier. The gelatex component is present in the carrier as a stable dispersion and is substantially uniformly depleted as multiple copies are produced, resulting in a significantly reduced rate of image density deterioration as multiple copies are produced.