Method of making a lithographic printing plate
View Patent ↗A method of making a lithographic printing plate includes the steps of: a) providing a lithographic printing plate precursor including (i) a support having a hydrophilic surface or which is provided with a hydrophilic layer, (ii) a coating on the support including a photopolymerizable layer and, optionally, an intermediate layer between the photopolymerizable layer and the support, wherein the photopolymerizable layer includes a polymerizable compound, a polymerization initiator and a binder, b) image-wise exposing the coating in a plate setter, c) heating the precursor in a pre-heating unit within a time period of less than 10 minutes after step (b), d) treating the precursor in a gumming station, including at least one gumming unit, whereby a gum solution is applied to the precursor, thereby removing non-exposed areas of the photopolymerizable layer from the support and gumming the plate in a single step.
1. A method of making a lithographic printing plate comprising the steps of:
a) providing a lithographic printing plate precursor including a support having a hydrophilic surface or which is provided with a hydrophilic layer, a coating on the support including a photopolymerizable layer and, optionally, an intermediate layer between the photopolymerizable layer and the support, wherein the photopolymerizable layer includes a polymerizable compound, a polymerization initiator, and a binder;
b) image-wise exposing the coating by a laser in a plate setter;
c) heating the precursor in a preheating unit within a time period of less than 10 minutes after step (b); and
d) treating the precursor in a gumming station, including at least one gumming unit, whereby a gum solution is applied to the precursor, thereby removing non-exposed areas of the photopolymerizable layer from the support and gumming the plate in a single step; wherein
the gum solution has a pH-value ranging between 3 and 9.
2. A method according to claim 1 , wherein the time period is less than 5 minutes.
3. A method according to claim 1 , wherein the time period is less than 1 minute.
4. A method according to claim 1 , wherein in step (c) the precursor is heated in the preheating unit at a temperature ranging between 80° C. and 150° C.
5. A method according to claim 1 , wherein in step (c) the precursor is heated in the preheating unit for a dwell time ranging between 5 seconds to 1 minute.
6. A method according to claim 1 , wherein the preheating unit is provided with a heating element.
7. A method according to claim 6 , wherein the heating element is an IR-lamp, a UV-lamp, heated air, or a heated metal roll.
8. A method according to claim 1 , wherein the preheating unit is coupled to the gumming unit by a mechanical plate conveying device.
9. A method according to claim 1 , wherein the preheating unit is coupled to the plate setter by a mechanical plate conveying device wherein the precursor is shielded from ambient light.
10. A method according to claim 1 , wherein the preheating unit is coupled to the gumming unit by a mechanical plate conveying device and wherein the preheating unit is further coupled to the plate setter by a mechanical plate conveying device wherein the precursor is shielded from ambient light.
11. A method according to claim 1 , wherein the laser emits violet light.
12. A method according to claim 1 , wherein the laser emits infrared light.