Engelhard Minerals & Chemicals Corporation

Peter A Isaac

T Dixon Oulton

Walter L Haden, Jr

Novel pressure-sensitive manifold record material comprises paper coated on one side with an encapsulated solution of an alkali-sensitive color precursor such as phenolphthalein in a polar solvent and coated on the reverse side or on a separate sheet of paper with particles of a white alkaline pigment such as fluid energy milled lime. The sheets are assembled for manifold record material by stacking sheet material coated with encapsulated dye solution in face-to-face relationship with surfaces coated with alkaline pigment. Upon rupture of the capsules by printing pressure, a colored mark is formed on the surface containing the alkaline pigment particles.

Pressure-sensitive record material and preparation thereof

Preparation of so-called 'reduced charge' montmorillonite or bentonite pigment from a naturally-occurring crude clay containing dioctahedral montmorillonite by ion-exchanging cations in the clay with hydrogen ions while the clay is in slurry form, filtering, pugging the filter cake with a preselected amount of a neutral or alkaline lithium salt, preferably the oxide, hydroxide or carbonate, and heat treating to collapse the mineral structure.

Production of reduced charge montmorillonite pigment

A sheet coated with a reduced charge montmorillonite pigment for use in record material, especially pressure-sensitive carbonless copying systems. The pigment is produced by replacing exchangeable cations of a substantially dioctahedral montmorillonite (exemplified by certain bentonite clays) with lithium ions, mildly heating the lithium-exchanged montmorillonite to collapse irreversibly the montmorillonite structure, and grinding the heat-treated material to pigment-size particles. The sheets produce stabilized intense images when printed with a solution of crystal violet lactone (CVL) dye precursor and thus may be used with CVL without employing secondary slow acting dyes such as benzoyl leuco methylene blue. The sheets are also useful with other colorless or substantially colorless dye precursors.

Record sheets sensitized with reduced charge montmorillonite pigment

A sheet coated with a reduced charge montmorillonite pigment for use in record material, especially pressure-sensitive carbonless copying systems. The pigment is produced by replacing exchangeable cations of a dioctahedral montmorillonite (exemplified by certain bentonite clays) with lithium ions, mildly heating the lithium-exchanged montmorillonite to collapse irreversibly the montmorillonite structure, and grinding the heat-treated material to pigment-size particles. The sheets produce stabilized intense images when printed with a solution of crystal violet lactone (CVL) dye precursor and thus may be used with CVL without employing secondary slow acting dyes such as benzoyl leuco methylene blue. The sheets are also useful with other colorless or substantially colorless dye precursors.

A reduced charge montmorillonite pigment useful as a color-former in record material, especially pressure-sensitive carbonless copying record systems. The pigment is produced by replacing exchangeable cations of a selected dioctahedral montmorillonite crude clay (exemplified by certain bentonite clays) with a predetermined amount of lithium ions, mildly heating the lithium-exchanged montmorillonite to collapse irreversibly the montmorillonite structure, and grinding the heat-treated material to pigment-size particles, the grinding preferably being carried out in a fluid energy mill. When the pigment particles are coated on paper, the coated sheets produce stabilized intense images when printed with a solution of crystal violet lactone (CVL) dye precursor and thus may be used in record material with CVL without employing secondary slow acting dyes such as benzoyl leuco methylene blue. The sheets are also useful with other colorless or substantially colorless dye precursors.

Reduced charge montmorillonite pigment for sensitizing record material

A reduced charge montmorillonite pigment useful as a colorformer in record material, especially pressure-sensitive carbonless copying record systems. The pigment is produced by replacing exchangeable cations of a selected dioctahedral montmorillonite crude clay (exemplified by certain bentonite clays) with a predetermined amount of lithium ions, mildly heating the lithium-exchanged montmorillonite to collapse irreversibly the montmorillonite structure, and grinding the heat-treated material to pigment-size particles, the grinding preferably being carried out in a fluid energy mill. When the pigment particles are coated on paper, the coated sheets produce stabilized intense images when printed with a solution of crystal violet lactone (CVL) dye precursor and thus may be used in record material with CVL without employing secondary slow acting dyes such as benzoyl leuco methylene blue. The sheets are also useful with other colorless or substantially colorless dye precursors.

Growing community of inventors

Summit, NJ, United States of America

Peter A Isaac