THERMORECORDING

A heat sensitive recording layer which is normally permeable by water and consists essentially of a hydrophilic binder having generally homogenously distributed therethrough finely divided particles of a hydrophilic thermoplastic polymer softening at at least about 10 DEG C above room temperature and also containing therein finely divided dye or pigment capable of absorbing electromagnetic radiation and converting the same into heat, is exposed while in heat conductive contact with the radiation absorptive image markings of an original to be reproduced for a time not greater than 101 second to electromagnetic radiation of an intensity of at least 0.3 Watt. sec per sq.cm and sufficient to heat the areas of the layer corresponding to the non-image areas of the original to reduce the water permeability thereof; and is then treated with an aqueous liquid to develop the image therein by selective permeation by the aqueous liquid of the areas of unchanged permeability.