Analysis of the Dye Transfer Mechanism in Heat Transfer Printing.

When heat is applied to the back of a paper printed with sublimable disperse dyes, the dye is transferred by the following mechanism: sublimation, diffusion in the gas phase, supersaturation, condensation in the fiber structure and finally diffusion in the fiber phase. A dye transfer model is presented showing the effects of dwell time, transfer temperature and pressure on color transfer efficiency. Also, examples are given of the kinetic and thermodynamic analysis required in determining the suitability of dyes for heat transfer printing.