Non-permanent inkjetted flexographic mask
View Patent ↗A method for making a printing plate is disclosed comprising mounting a printing plate to a holder; applying a non-permanent patterned coating to an outer surface of the printing plate by moving a coating applicator relative to the holder; and, exposing the printing plate to actinic radiation through the patterned coating without removing the printing plate from the holder. The invention avoids handling-induced damage by performing coating and exposure steps in a single apparatus.
1. A method for exposing a photosensitive printing plate, the method comprising:
mounting the printing plate to a holder;
imagewise applying a non-permanent photomask to a surface of the printing plate using a coating applicator;
establishing relative motion between the holder and the coating applicator; and,
exposing the printing plate to actinic radiation through the non-permanent photomask without removing the printing plate from the holder wherein applying the non-permanent photomask comprises applying a hydrophobic ink to the printing plate.
2. A method as in claim 1 , wherein applying the non-permanent photomask comprises ejecting an inkjet droplet pattern from an inkjet printhead.
3. A method as in claim 2 , wherein the imagewise applying comprises applying an ink comprising a substantially non-volatile solvent.
4. A method as in claim 3 , wherein the substantially non-volatile solvent comprises a wax.
5. A method as in claim 3 , wherein the substantially non-volatile solvent comprises an oil.
6. A method as in claim 3 , wherein the imagewise applying comprises at least partially curing the non-permanent photomask on the surface of the printing plate before exposing the printing plate to the actinic radiation.
7. A method as in claim 6 , wherein the non-permanent photomask remains liquid during exposing the printing plate.
8. A method for exposing a photosensitive printing plate, the method comprising:
mounting the printing plate to a holder;
imagewise applying a non-permanent photomask to a surface of the printing plate using a coating applicator;
establishing relative motion between the holder and the coating applicator; and,
exposing the printing plate to actinic radiation through the non-permanent photomask without removing the printing plate from the holder wherein the non-permanent photomask remains liquid during exposing the printing plate and the method comprises removing the non-permanent photomask without de-mounting the printing plate from the holder wherein the removing comprises using one of a blanket cleaner and a water jet.
9. A method for exposing a photosensitive printing plate, the method comprising:
mounting the printing plate to a holder;
imagewise applying a non-permanent photomask to a surface of the printing plate using a coating applicator;
establishing relative motion between the holder and the coating applicator; and,
exposing the printing plate to actinic radiation through the non-permanent photomask without removing the printing plate from the holder wherein the non-permanent photomask remains liquid during exposing the printing plate and the method comprises removing the non-permanent photomask without de-mounting the printing plate from the holder wherein the removing comprises applying printing ink to the printing plate.
10. A method for exposing a photosensitive printing plate, the method comprising:
mounting the printing plate to a holder;
imagewise applying a non-permanent photomask to a surface of the printing plate using a coating applicator;
establishing relative motion between the holder and the coating applicator; and,
exposing the printing plate to actinic radiation through the non-permanent photomask without removing the printing plate from the holder;
wherein the non-permanent photomask remains liquid during exposing the printing plate and, the non-permanent photomask comprises a hydrophobic liquid.
11. A method as in claim 10 , wherein the hydrophobic liquid comprises a hydrophobic liquid ink.
12. A method as in claim 11 , wherein the non-permanent photomask comprises a non-adherent inkjet dot pattern.
13. A method as in claim 11 , comprising providing a baffle coated with an adsorptive material to shield the printing plate from scattered light during the exposing.
14. A method for exposing a photosensitive printing plate, the method comprising:
mounting the printing plate to a holder;
imagewise applying a non-permanent photomask to a surface of the printing plate using a coating applicator;
establishing relative motion between the holder and the coating applicator; and,
exposing the printing plate to actinic radiation through the non-permanent photomask without removing the printing plate from the holder:
wherein the non-permanent photomask remains liquid during exposing the printing plate, the non-permanent photomask comprises a hydrophobic liquid, and the hydrophobic liquid comprises a hydrophobic liquid ink, the method comprising removing the non-permanent photomask after the exposing wherein the liquid ink remains liquid during the removing of the photomask.
15. A method as in claim 14 , comprising:
performing the imagewise applying while moving the coating applicator relative to the holder; wherein the non-permanent photomask comprises a non-adherent inkjet dot pattern and the coating applicator comprises an inkjet printhead; and,
subsequently removing the non-permanent photomask from the surface without de-mounting the printing plate from the holder.
16. A method as in claim 14 , comprising:
at least partly curing the non-permanent photomask before the exposing of the printing plate; and,
removing the non-permanent photomask from the surface without de-mounting the printing plate from the holder.
17. A method as in claim 16 , wherein:
removing the non-permanent photomask from the surface comprises using at least one of a blanket cleaner, a water jet and the process of applying printing ink to the printing plate.