Abstract: Pressure-sensitive mark-recording systems of chromogens comprised of diphenylmethane derivatives in solution with selected diester solvents is disclosed as well as pressure-sensitive mark-recording systems comprised of (a) sheet material, (b) mark-forming components supported by the sheet material and arranged in juxtaposition but in unreactive condition, a chromogen, and an acid clay sensitizer for the chromogen, and (c) the solvent supported by the sheet material but separated from the sensitizing agent by a physical barrier which is rupturable on the application of a marking instrument to the sheet material.

Abstract: A pressure-sensitive mark-recording system comprising (a) sheet material, (b) mark-forming components supported by the sheet material and arranged in juxtaposition comprising a chromogen material and an acid clay sensitizing agent for the chromogenic material which produces a color from the chromogenic material when brought into contact with the chromogenic material in the presence of a solvent for the chromogenic material with the solvent supported by the sheet material but separated from its sensitizing agent by a physical barrier which is rupturable on the application of the marking instrument to the sheet material, the invention characterized in that the liquid solvent is a solvent comprised of a blend of aromatic hydrocarbon components in which at least one-half the carbon atoms are benzenoid or a mixture of such hydrocarbons, and a diester component.

Abstract: Oil droplets are encapsulated by forming a dispersion of the droplets in an aqueous alkaline liquid medium containing a water-soluble salt of a polycarboxylate polymer and acidifying the medium to a pH in the range of 5 to 8 whereby the polycarboxylate polymer precipitates to form walls around the droplets.