Abstract 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*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 10 1 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.
A method for reproducing an original according to claim 1, wherein said material is a finely divided dye or pigment which absorbs visible light in at least a portion of the whole visible spectrum.
Claim 2
Dependent Claim
18 words
A method according to claim 1, wherein the exposure time is between 10 2 and 10 4 second.
Claim 3
Dependent Claim
43 words
A method for reproducing information according to claim 1, wherein said layer is prepared starting from an aqueous dispersion of said thermoplastic polymer particles and said particles are used in a ratio greater than 3:2 by weight in respect of the hydrophilic binder.
Claim 4
Dependent Claim
18 words
A method for reproducing an original according to claim 1, wherein the hydrophilic binder is a water-soluble colloid.
Claim 5
Dependent Claim
21 words
A method for reproducing an original according to claim 5, wherein the said colloid is soluble in water at room temperature.
Claim 6
Dependent Claim
16 words
A method for reproducing an original according to claim 5, wherein the hydrophilic binder is gelatin.
Claim 7
Dependent Claim
16 words
A method for reproducing an original according to claim 6, wherein the said colloid is poly(N-vinylpyrrolidone).
Claim 8
Dependent Claim
24 words
A method for reproducing an original according to claim 1, wherein the said hydrophobic polymer particles soften between 10* and 200*C above room temperature.
Claim 9
Dependent Claim
23 words
A method for reproducing an original according to claim 1, wherein said polymer particles are sized from 0.1 Mu to 50 Mu .
Claim 10
Dependent Claim
22 words
A method for reproducing an original according to claim 1, wherein the recording layer contains a wetting agent for the hydrophobic polymer.