Polymer Plates
I have ordered polymer plates and they have curled to the point that they cannot be flattened down to print. Can anybody shed some light on why they are curling? Some older ones are curled so much that if flattened down they crack apart. They were all ordered from a reputable place and I am trying to find out if this is inherent o the material or is it atmospheric. Some of the material hasn’t even been used and still in the original plastic envelope.
How have you stored them? They should be stored in a cool, dry place, away from heat, light and ozone sources such as some electric motors. Especially, keep them away from sunlight and fluorescent lights, with compact fluorescents being the worst of the fluorescent lights.
Don’t forget that during the processing of the plates, light is what polymerizes (hardens) the photopolymer. So, if you store the plates under sunlight or fluorescent light, they will slowly continue to polymerize. This makes them progressively less flexible, so when you bend them, they are more likely to crack.
iwillcreate, I have had success by soaking a curled plate in a
bath of room temperature water for about 15 -20 minutes.
I leave on the adhesive back and it’s protector.
The plate after the water bath the plate needs to be dryed
again. The photopolymer plates are hygroscopic,they are sensitive to humidity or lack there of. best james
iwillcreate, If you have only had these plates for a short time, and If you have taken care to protect them from light and moisture then it is possible that there is an issue in the production process that may need to be corrected.
When polymer plates are made they are exposed to light for a specific period, then developed and dryed. After that they are exposed to light agian for a specific period to give them the proper overall hardness. If they don’t get that second exposure they may get soft or even gooey later. If they get way too much light during second exposure they may get too hard and possibly crack.
If all your plates coming from your platemaker exhibit this issue then It’s possible someone is using the wrong exposure. If I were having this issue and I knew that I wasn’t the cause then I would certainly talk to the platemaker and discuss the issue with them.