Variable lithographic printing process
View Patent ↗A variable lithographic printing process includes absorbing a release agent into an imaging member; forming a later image by evaporating the release agent from selective locations on an imaging member surface; developing the latent image; and transferring the developed image to a receiving substrate. The release agent diffuses through the imaging member surface.
1. A process for variable lithographic printing, comprising:
absorbing a release agent into an imaging member comprising an imaging member surface, wherein the imaging member surface is porous;
forming a latent image by evaporating the release agent from selective locations at the imaging member surface to form hydrophobic non-image areas and hydrophilic image areas;
developing the latent image by applying an ink composition to the hydrophilic image areas to form a developed image; and
transferring the developed image to a receiving substrate;
wherein the imaging member is a foam or a sponge.
2. The process of claim 1 , wherein the absorbed release agent diffuses to the imaging member surface to enhance the transferring.
3. The process of claim 1 , wherein the release agent is a volatile silicone liquid.
4. The process of claim 3 , wherein the volatile silicone liquid is octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), hexamethyldisiloxane (OS10), or octamethyltrisiloxane (OS20).
5. The process of claim 1 , wherein the evaporating is performed by laser heating, flash heating, or contact heating.
6. The process of claim 1 , wherein the foam or sponge comprises an elastomeric material and a radiation-absorbing filler dispersed therein.
7. The process of claim 6 , wherein the radiation absorbing filler is carbon black.
8. The process of claim 6 , wherein the elastomeric material comprises a silicone rubber.
9. The process of claim 1 , wherein the imaging member comprises an elastomeric material and a radiation-absorbing filler dispersed therein.
10. The process of claim 9 , wherein the elastomeric material comprises a silicone rubber.
11. The process of claim 1 , wherein the receiving substrate is moving at a rate of greater than about 1 meter per second when the latent image is transferred.
12. The process of claim 1 , wherein the receiving substrate is moving at a rate of greater than about 2 meters per second when the latent image is transferred.