Color thermal ink-transfer imaging

A new thermal ink-transfer color printer has recently been developed. This color printer adopts a line sequential system in which a tape-typed ink ribbon coated with three colors of ink in series is used with a serial print head. With this new printer, control of the heating pulsewidth in accordance with the history of the printed data and the temperature of the print head substrate make it possible to realize high-quality color printing. As a result of measuring the spectral reflectance and chromaticities of the colors this printer can produce, it was possible to discern that 1) three ink colors (yellow, magenta, and cyan) are appropriate for use as primaries for color printing; 2) the color gamut possible with this printing method is as great as graphic arts; and 3) yellow, magenta, and cyan was found to be the best order ot the overlapping transfer. To clarify the characteristics of multicolor printing using dot-patterns, the color differences for all 2 × 2 dot-patterns were evaluated. Their chromaticities were analyzed on the basis of Neugebauer's equation, MacAdam's tristimulus values, and simple models that included changes in dot area.