Abstract: Pressure-sensitive material for use in a copy system comprising a substrate bearing isolated droplets, e.g., in microcapsules, of an oily solvent are provided with an acid-sensitive chromogenic compound and a phenolic ester, said phenolic ester being an oil soluble compound that is capable of stabilizing the colored marking. Upon release of the chromogen and the phenolic ester from the microcapsules or the like, the ester is hydrolyzed in the presence of moisture and an acidic material to form the corresponding phenol, which in turn, stabilizes the colored marking. In such form, the phenolic compound will not prematurely react with the chromogen, and it is shielded from any chemical reaction with materials in other parts of the copy system.

Abstract: Pressure-sensitive microcapsules containing a solvent composition for use in carbonless copy systems for use in the absence of a halogenated solvent consisting essentially of a combination of a mono-alkyl naphthalene, wherein said alkyl group contains from 1 to 3 carbon atoms per molecule and a di-alkyl naphthalene, wherein each of said alkyl groups in said di-alkyl naphthalene contains from 2 to 4 carbon atoms per molecule, said mono-alkyl naphthalene being present in an amount between about 25 and about 40 percent by weight of the alkylated naphthalenes present in the solvent, and an isocyanate cross-linking agent.

Abstract: Pressure-rupturable, oil-containing microcapsules are produced by admixing a water-immiscible, oily material containing an oil-soluble, non-polymeric polyfunctional isocyanate cross-linking agent, and an aqueous solution of a polymeric emulsifying agent in the form of a water-soluble polymer containing recurring --NH.sub.2 or .dbd.NH groups or a water-soluble natural gum containing recurring hydroxy groups. An oil-in-water emulsion is formed containing the isocyanate dispersed in the form of microscopic emulsion droplets in the aqueous continuous phase containing the emulsifying agent, and a solid capsule wall is formed by the cross-linking of the emulsifying agent by the isocyanate. Emulsions utilizing the natural polymeric emulsifying agents preferably contain a viscosity lowering agent in the form of a urea-formaldehyde or alkali metal periodate in order to obtain a higher solids coat weight while at an efficient coating viscosity.

Abstract: A substantially colorless bisfluoran chromogenic material having the structural formula ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group;X and Y each represent a hydrogen atom, a halogen atom, an hydroxyl group, an alkyl group, a nitro group, an amino group, an acyl group, or a carboalkoxy group;Z represents an oxy radical, a carbonyl group, an alkylene group, an alkylidene group, a sulfonyl group, or a thio radical; andn represents an integer from 0 to 1.The bisfluoran compounds are produced by reacting a 4-dialkylamino-2-hydroxy-2'-carboxybenzophenone with a diphenol wherein the diphenol is unsubstituted in at least one of the positions ortho to an hydroxyl group in each of the phenyl rings. The bisfluorans are used in pressure-sensitive copy systems comprising a support bearing microcapsules containing the bisfluorans, alone, or in combination with other color-forming materials.