Image transfer product including a thin printing surface layer
View Patent ↗An image transfer product such as an offset printing blanket or sleeve is provided which comprises a very thin printing surface layer in combination with a smooth image reinforcement layer comprising a polymeric film, a fabric, or a polymer-coated fabric. The thin printing surface layer has a thickness between about 0.001 to about 0.012 inches (about 0.025 to about 0.3 mm). The image transfer product is more efficiently manufactured due to reduced solvent usage and reduced number of coating passes, and in use, exhibits uniform feed, web control, and registration characteristics.
1. An image transfer product comprising a printing blanket or sleeve comprising a thin printing surface layer having a thickness of between about 0.001 to about 0.012 inches (about 0.025 to about 0.3 mm) over an image reinforcement layer selected from the group consisting of a 100% solids thermoplastic or thermosetting polyurethane or alloys thereof which is free of reinforcing fibers, a fabric having a denier of 150 or less, or a fabric coated with a polymer such that said fabric has a smooth surface.
2. The image transfer product of claim 1 comprising a printing blanket; said blanket including a blanket carcass with the image reinforcement layer over the blanket carcass or comprising the uppermost layer of the blanket carcass, and the thin printing surface layer over the image reinforcement layer.
3. The image transfer product of claim 2 wherein said blanket carcass comprises at least one base ply comprised of fabric, film, a polymeric composite material, or metal.
4. The image transfer product of claim 1 comprising a printing sleeve including a base sleeve comprising a rigid metal, polymer, or polymer composite, where the image reinforcement layer is over the base sleeve and the thin printing surface layer is over the image reinforcement layer.
5. The image transfer product of claim 2 wherein said blanket carcass further includes a compressible layer.
6. The image transfer product of claim 4 including a compressible layer over said base sleeve.
7. The image transfer product of claim 1 wherein said printing surface layer has a thickness of between about 0.002 to about 0.007 inches (about 0.05 to about 0.18 mm).
8. The image transfer product of claim 1 wherein said printing surface layer is selected from nitrile rubber, hydrogenated nitrile butadiene rubber, polysulfide rubber, butyl rubber, EPDM rubber, thermoplastic and thermosetting polyurethanes, and mixtures or alloys thereof.
9. The image transfer product of claim 1 wherein said image reinforcement layer comprises a woven polyester fabric.
10. The image transfer product of claim 1 wherein said image reinforcement layer comprises a fabric coated with a polymer.
11. The image transfer product of claim 10 wherein said polymer is selected from nitrile rubber, hydrogenated nitrile butadiene rubber, butyl rubber, EPDM rubber, polyvinyl chloride, polyurethanes, and mixtures or alloys of the above materials.
12. The image transfer product of claim 1 wherein said image reinforcement layer comprises a fabric having a polymeric film laminated to its surface.
13. A method of making an image transfer product comprising a printing blanket or printing sleeve having a thin printing surface layer comprising:
providing a blanket carcass or base sleeve;
applying an image reinforcement layer to said blanket carcass or base sleeve, said image reinforcement layer selected from the group consisting of a 100% solids thermoplastic or thermosetting polyurethane or alloys thereof which is free of reinforcing fibers, a fabric having a denier of 150 or less, or a fabric coated with a polymer such that said fabric has a smooth surface; and
applying a printing surface layer having a thickness of between about 0.001 to 0.012 inches (about 0.025 to about 0.3 mm) to said image reinforcement layer.
14. The method of claim 13 further including applying a compressible layer to said blanket carcass or base sleeve prior to applying said image reinforcement layer.
15. The method of claim 13 wherein said base sleeve comprises a rigid metal, polymer, or polymer composite support sleeve.
16. The method of claim 13 wherein said printing surface layer is applied by knife-over-roll coating, calendering, non-electrostatic and electrostatic spray coating, or extrusion-lamination.
17. The method of claim 13 wherein said image reinforcement layer comprises a 100% solids polyurethane which is applied in liquid form by knife-over-roll coating, calendering, pneumatic or electrostatic spray coating, slot die coating, or extrusion.
18. The method of claim 13 wherein said image reinforcement layer is applied by lamination.