Abstract: A pen printer for converting data into printed form on a print sheet placed on a platen. The pen printer comprises a plurality of ink pens and a pen carriage mounted for reciprocating movement above the platen. The pen carriage has a device for removably attaching each of the ink pens juxtaposed in the direction of movement of the carriage. Pen actuators are mounted on the pen carriage apart from the ink pens with each pen actuator being responsive to an electrical signal for bringing a corresponding one of the ink pens toward the platen into contact with the print sheet. The pen printer also comprises a carriage actuator responsive to an electrical signal for moving the pen carriage and a sheet feed mechanism responsive to arrival of the pen carriage to at least one of first and second predetermined positions separated from each other for feeding the print sheet a predetermined length on the platen.

Abstract: A printing paper for thermal transfer printing comprising a substrate, and a dye acceptor layer formed on one surface of the substrate to accept a sublimable dye transferred from a dye carrier ribbon in contact with the dye acceptor layer upon selective heating of the dye carrier ribbon. The dye acceptor layer has a cumulative pore volume of 0.2 to 0.6 cm.sup.3 /g and contains a pigment in the form of particles whose median particle diameter of from 0.2 to 2 .mu.m. In particular, the dye acceptor layer is made of a coating of a resinous binder uniformly dispersing a pigment therein, the coating being impregnated with a resin having good affinity for the sublimable dye.