Printing element with an integral printing surface
A relief image printing element with an integral imageable printing surface and a method of preparing the relief image printing element are described. The relief image printing element comprises a dimensionally stable base layer; a floor layer comprised of a cured polymer selected from the group consisting of photopolymers, and polymers with a resilience of at least 40% when cured; and at least one layer of an imageable material. Most preferably, the floor layer created by curing the layer through the top of the printing element by face exposure. The printing element may also contain a compressible layer between the base layer and the floor layer.
1 - 15 . (canceled)
16 . A method of preparing a substantially planar photosensitive relief image printing element with an integral imageable surface, comprising the steps of:
a. providing a dimensionally stable base layer;
b. applying a floor layer comprised of a polymer selected from the group consisting of photopolymers, and polymer with a resilience of at least 40% when cured over the dimensionally stable base layer;
c. curing the floor layer from the top of the floor layer;
d. adjusting the floor layer to a desired thickness;
e. applying at least one imageable layer on top of the cured floor layer;
f. optionally, applying a masking layer on top of the imageable layer; and
g. optionally, applying a removable coversheet over the at least one imageable layer or the optional masking layer.
17 . The method according to claim 16 , wherein the floor layer is fully cured before the at least one imageable layer is applied.
18 . The method according to claim 16 , wherein the base layer comprises a cured polymer resin.
19 . The method according to claim 16 , wherein the printing element also comprises a layer of compressible material between the dimensionally stable base layer and the floor layer.
20 . The method according to claim 16 , wherein the floor layer comprises a photopolymer.
21 . The method according to claim 16 , wherein the imageable material comprises a photopolymer.
22 . The method according to claim 17 , wherein the base layer comprises a fiber reinforced polymer.
23 . The method according to claim 18 , wherein the compressible material has a Shore A hardness of from 30 to 70 and a resilience of from 40 to 70%.
24 . The method according to claim 19 , wherein the photopolymer comprises an A-B-A type block copolymer.
25 . The method according to claim 20 , wherein the photopolymer comprises an A-B-A type block copolymer.
26 . The method according to claim 21 , wherein the masking layer is selectively ablatable using laser energy at a selected wavelength and power.
27 . The method according to claim 16 , wherein the floor layer also comprises microspheres.
28 . A method of doing business comprising the steps of:
a. obtaining from a printing plate manufacturer desired relief image printing plate specifications selected from the group consisting of thickness, resilience, hardness, durometer, and combinations thereof;
b. preparing a printing element having a pre-cured floor layer according to said desired specifications, wherein the print element comprises
i) a dimensionally stable base layer;
ii) floor layer comprised of a cured polymer selected from the group consisting of photopolymers and polymers, each with a resilience of at least 40% when cured; and
iii) at least one layer of an uncured photopolymer; and
c. supplying the printing element having the pre-cured floor layer to the printing plate manufacturer for subsequent imagewise exposure and development to produce the relief image printing plate;
wherein a back exposure step is not performed by the printing plate manufacturer.
29 . A method according to claim 28 wherein the printing element comprises a masking layer on top of the at least one layer of an uncured photopolymer.
30 . A method according to claim 28 , wherein the printing element comprises a removable coversheet on top of the layer of an uncured photopolymer.
31 . A method according to claim 28 , wherein the printing element comprises a layer of compressible material between the dimensionally stable base layer and the floor layer.
32 . A method according to claim 29 , wherein the printing element comprises a removable coversheet on top of the masking layer.
33 . A method according to claim 32 wherein the masking layer is selectively ablatable by the printing plate manufacturer using laser energy at a selected wavelength power.
34 . A method according to claim 28 wherein the floor layer also comprises microspheres.