The Gillette Company

Edward J Ferguson

Henry Peper

Thomas E Eaton

A writing instrument cartridge contains a loose fitting ball follower disposed within the cartridge between an end of a column of paste like ink exhibiting a yield value, and compressed gas contained in a sealed end of the cartridge. The ball follower is adapted to help peel the ink from the tube walls without contact and to prevent the gas from channeling through the ink and escaping from the cartridge past a ball point or nib during writing.

Pressurized cartridge for a writing instrument

An erasable ink containing a thermoplastic block copolymer, pigment particles, and a solvent. In a preferred embodiment, an erasable ink requiring little or no pressurization is provided by employing a mixture of radial and linear block copolymers and a mixed solvent system falling within a specific range of solubility parameter. Polybutene and poly-alpha-methylstyrene are preferred additives to decrease smearing tendency.

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Avon, MA, United States of America

Edward J Ferguson