Humid media transfer device and/or printing media transfer device of printing machines
The invention relates to the use of a roller or a rubber blanket with a covering made of elastomeric material with an outer surface for indirect or direct transfer of a damping solution and/or a printing agent to a print carrier of a printing press. In order to enable a virtually optimum printing result, even in the presence of changing process conditions, and to display improved back-transfer properties with unchanging properties over the service life, it is proposed that a roller/rubber blanket be used which has an outer surface that constitutes an elastomeric surface coating of the covering and contains, or completely consists of, a fluoroelastomer, particularly an elastomeric fluorinated rubber. The fluorinated rubber can, in particular, be a tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer.
1. Roller or rubber blanket for a printing press, particularly an offset printing press, or roller as a laminating roller in a laminating system, where the roller or the rubber blanket comprises a covering made of an elastomeric material with an outer surface for transferring damping solution and/or printing agent in the printing press, in order to indirectly or directly transfer a damping solution and/or a printing agent to a print carrier, where the outer surface transferring the damping solution and/or the printing agent is provided by an elastomeric surface coating of the covering, wherein the surface coating contains a fluoroelastomer, and the surface coating displays a layer thickness less than/equal to 100 μm and a roughness Ra less than/equal to 1 μm, wherein the surface coating displays a wetting angle in relation to water of ≧80° and/or a wetting angle in relation to diiodomethane of ≧60°.
2. Roller or rubber blanket according to claim 1 , characterized in that the surface of the surface coating has a roughness Ra less than/equal to 0.4 μm.
3. Roller or rubber blanket according to claim 1 , characterized in that the fluoroelastomer is formed by a fluorinated rubber latex.
4. Roller or rubber blanket according to claim 1 , characterized in that the fluorine content of the surface coating is in the range from approx. 64% by weight to approx. 75.5% by weight, referred to the polymeric coating components or to the surface coating as a whole.
5. Roller or rubber blanket according to claim 1 characterized in that the surface coating is not perfluorinated, and in that the atomic ratio of fluorine:hydrogen in the surface coating is greater than/equal to 5:1.
6. Roller or rubber blanket according to claim 1 , characterized in that the fluoroelastomer contains vinyl fluoride and/or vinylidene fluoride monomer units.
7. Roller or rubber blanket according to claim 1 characterized in that the fluoroelastomer is or encompasses a terpolymer.
8. Roller or rubber blanket according to claim 1 characterized in that the fluoroelastomer comprises a tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride terpolymer.
9. Roller or rubber blanket according to claim 1 characterized in that the fluoroelastomer is contained in the coating, particularly as a terpolymer, in a proportion of 5 to 98% by weight to 100 parts by weight of the coating.
10. Roller or rubber blanket according to claim 1 characterized in that the surface coating containing the fluoroelastomer additionally contains a non-elastomeric polymer, including a fluoropolymer.
11. Roller or rubber blanket according to claim 10 characterized in that the non-elastomeric polymer, including a non-elastomeric fluoropolymer, is contained in the surface coating in a proportion of 5 to 75% by weight to 100 parts by weight elastomer.
12. Roller or rubber blanket according to claim 1 characterized in that the elastomeric fluoropolymer is a block polymer.
13. Roller or rubber blanket according to claim 1 characterized in that the surface coating containing the fluoroelastomer displays a thickness of up to 50 μm.
14. Roller or rubber blanket according to claim 1 , characterized in that the surface coating displays an elongation at break of >100%, or reversible extensibility of >50%, or both.
15. Printing press, particularly an offset printing press, with a roller and/or a rubber blanket according to claim 1 .
16. Roller or rubber blanket for a printing press, particularly an offset printing press, or roller as a laminating roller in a laminating system, where the roller or the rubber blanket comprises a covering made of an elastomeric material with an outer surface for transferring damping solution and/or printing agent in the printing press, in order to indirectly or directly transfer a damping solution and/or a printing agent to a print carrier, where the covering is applied to a stable roller core or a blanket, wherein an adhesive or primer layer is located between the surface coating and the elastomeric covering, where the outer surface transferring the damping solution and/or the printing agent is provided by an elastomeric surface coating of the covering, the surface coating contains a fluoroelastomer, wherein the surface coating displays a layer thickness less than/equal to 100 μm and a roughness Ra less than/equal to 1 μm and wherein the elastomeric material of the covering has a hardness of 15 to 100 Shore A.
17. Roller or rubber blanket for a printing press, particularly an offset printing press, or roller as a laminating roller in a laminating system, where the roller or the rubber blanket comprises a covering made of an elastomeric material with an outer surface for transferring damping solution and/or printing agent in the printing press, in order to indirectly or directly transfer a damping solution and/or a printing agent to a print carrier, where the covering is applied to a stable roller core or a blanket, wherein an adhesive or primer layer is located between the surface coating and the elastomeric covering, wherein in a roller the radial thickness of the covering is from 1 to 50 mm and in a rubber blanket the thickness of the covering is from 1.5 to 5 mm, where the outer surface transferring the damping solution and/or the printing agent is provided by an elastomeric surface coating of the covering, the surface coating contains a fluoroelastomer, wherein the surface coating displays a layer thickness less than/equal to 100 μm and a roughness Ra less than/equal to 1 μm, wherein the elastomeric material of the covering has a hardness of 10 to 100 Shore A and wherein the filler content of the surface coating is less/equal to 10% by weight.
18. Roller or rubber blanket for a printing press, particularly an offset printing press, or roller as a laminating roller in a laminating system, where the roller or the rubber blanket comprises a covering made of an elastomeric material with an outer surface for transferring damping solution and/or printing agent in the printing press, in order to indirectly or directly transfer a damping solution and/or a printing agent to a print carrier, where the outer surface transferring the damping solution and/or the printing agent is provided by an elastomeric surface coating of the covering, characterized in that the surface coating contains a fluoroelastomer, and the surface coating displays a layer thickness less than/equal to 100 μm and a roughness Ra less than/equal to 1 μm, and wherein the fluoroelastomer is formed by a fluorinated rubber latex.
19. Rubber blanket for a printing press, particularly an offset printing press, where the rubber blanket comprises a covering made of an elastomeric material with an outer surface for transferring damping solution and/or printing agent in the printing press, in order to directly transfer a damping solution and/or a printing agent to a print carrier, where the covering is applied to a blanket, where the outer surface transferring the damping solution and/or the printing agent is provided by an elastomeric surface coating of the covering, wherein the elastomeric material of the covering has a hardness of 10 to 100 Shore A, and wherein the surface coating contains a fluoroelastomer, wherein the surface coating displays a layer thickness less than/equal to 100 μm and a roughness Ra less than/equal to 1 μm.