Ultra-fine textured digital lithographic imaging plate and method of manufacture
View Patent ↗A method of forming an imaging blanket for a printing apparatus comprises preparing a support structure (e.g., mold) for receipt of a polymer blanket compound, introducing the polymer blanket compound in liquid state over the support structure, curing the polymer blanket compound to produce an imaging blanket, releasing the imaging blanket from the support structure, and etching a surface of the imaging blanket to form a texture pattern therein, the surface forming an imaging surface of said imaging blanket. An imaging surface providing desirable dampening fluid retention is provided. Wet etch, dry etch or a combination of both may be used. The polymer may be a silicone compound, may include 3 percent by weight granular material.
1. A method of forming an elastomeric imaging blanket for a printing apparatus, the imaging blanket having an imaging surface configured to transfer an image to a substrate during a printing process of the printing apparatus, the method comprising:
preparing a mold for receipt of an elastomeric polymer blanket compound, the mold having an open surface for introduction of the elastomeric polymer blanket compound into the mold and a molding surface opposite the open surface;
introducing the elastomeric polymer blanket compound in liquid state into the mold at the open surface;
curing the elastomeric polymer blanket compound to produce the elastomeric imaging blanket, a first surface of the elastomeric imaging blanket being exposed to air during the curing, and a second surface opposite the first surface being in contact with the molding surface during the curing;
releasing the elastomeric imaging blanket from the mold; and
uniformly etching one of the first surface and the second surface of the elastomeric imaging blanket to form a texture pattern therein, the one of the first surface and the second surface forming the imaging surface of the elastomeric imaging blanket.
2. The method of claim 1 , wherein the polymer blanket compound is selected from the group consisting of: fluorosilicone, fluorocarbon-based synthetic rubber, and silicone.
3. The method of claim 2 , wherein the polymer blanket compound further comprises substantially 3-25 percent by weight carbon.
4. The method of claim 1 , wherein the etching is performed by a dry etch process.
5. The method of claim 4 , wherein the dry etch process comprises an anisotropic plasma etching process using a combination of CF 4 , SF 6 and O 2 species.
6. The method of claim 5 , wherein the dry etch process comprises a reactive ion etching process using a combination of CF 4 , SF 6 and O 2 species.
7. The method of claim 1 , wherein the etching is performed by a wet etch process.
8. The method of claim 7 , wherein the wet etch process comprises application of a solution of TBAF and NMP to the imaging surface.
9. The method of claim 1 , wherein the etching is performed by a combination of dry etching and wet etching.
10. The method of claim 1 , wherein the elastomeric polymer blanket compound has dispersed therein 3-25 percent by weight granular filler material.
11. The method of claim 10 , wherein the etching has a greater material removal rate for the polymer as compared to the granular material.
12. The method of claim 10 , wherein the etching has a greater material removal rate for the granular material as compared to the polymer.
13. The method of claim 10 , wherein the granular material comprises carbon.
14. The method of claim 1 , wherein the etching is configured to provide the imaging surface with a periodic surface roughness, Ra, of substantially between 0.1 and 1.5 microns.
15. The method of claim 1 , wherein the uniformly etching includes etching the first surface of the elastomeric imaging blanket to form the texture pattern therein.
16. The method of claim 1 , wherein the uniformly etching includes etching the second surface of the elastomeric imaging blanket to form the texture pattern therein.
17. A method of forming a molded elastomeric imaging blanket for a printing apparatus, the imaging blanket having an imaging surface configured to transfer an image to a substrate during a printing process of the printing apparatus, the method comprising:
preparing a mold structure for receipt of a fluorosilicone elastomeric blanket compound, the mold structure having at least one glass molding surface, the mold structure having an open surface for introduction of the elastomeric polymer blanket compound into the mold structure, the open surface being opposite the molding surface;
introducing the fluorosilicone elastomeric blanket compound in liquid state into the mold structure at the open surface, the fluorosilicone elastomeric blanket compound comprising dispersed 3-25 percent by weight carbon;
curing the blanket compound to produce the molded imaging blanket, a first surface of the imaging blanket being exposed to air during the curing, and a second surface opposite the first surface being in contact with the molding surface during the curing;
releasing the imaging blanket from the mold structure; and
uniformly etching the second surface of the imaging blanket formed in physical contact with the glass molding surface to form a texture pattern therein, the etched second surface forming the imaging surface of the imaging blanket.
18. The method of claim 17 , wherein the etching is performed by a dry etch process comprises an anisotropic reactive ion etching process using a combination of CF 4 and O 2 species.
19. The method of claim 17 , wherein the fluorosilicone elastomeric blanket compound comprises a granular material, the etching configured to provide a greater material removal rate for the fluorosilicone elastomeric blanket compound as compared to the granular material.
20. A method of forming a molded elastomeric imaging blanket for a printing apparatus, the imaging blanket having an imaging surface configured to transfer an image to a substrate during a printing process of the printing apparatus, the method comprising:
preparing a mold structure for receipt of a fluorosilicone elastomeric blanket compound, the mold structure having at least one glass molding surface, the mold structure having an open surface for introduction of the elastomeric polymer blanket compound into the mold structure, the open surface being opposite the molding surface;
introducing the fluorosilicone elastomeric blanket compound in liquid state into the mold structure at the open surface, said fluorosilicone elastomeric blanket compound comprising a dark tinted material with substantially 3-25 percent by weight carbon and granular material;
curing the fluorosilicone elastomeric blanket compound to produce the molded elastomeric imaging blanket, a first surface of the molded elastomeric imaging blanket being exposed to air during the curing, and a second surface opposite the first surface being in contact with the molding surface during the curing;
releasing the molded imaging blanket from the mold structure; and
uniformly etching the second surface of the imaging blanket formed in physical contact with the glass molding surface to form a texture pattern therein, the etched second surface forming the imaging surface of the imaging blanket, the etching configured to provide a greater material removal rate for the fluorosilicone elastomeric blanket compound as compared to the granular material;
the etching is further configured to provide the imaging surface with a periodic surface roughness, Ra, of substantially between 0.1 and 1.5 microns.