Are your polymer plates starting to curl at the edges?
Like our skin, plates can be affected by the weather and age. When humidity levels are low, the plates can look and feel brittle. And with the passage of time, the thinner polymer on the edges of the plates are pulled towards the denser polymer text and images on the front which causes curling. There is a natural aging of the plates as they do have a limited life expectancy but we can offer a few simple steps that can hydrate and give extra life to your plates.
Printight, maker of Toyobo plates KF95 and KF152, offers these suggestions if you have a platemaking system. Boxcar also gives similar steps for the majority of you who are without such equipment.
1. Place your plate back in the washout system for one minute or immerse in water. We suggest room temperature for a quick dunking, a minute may only be necessary if your plates are severely curled.
2. Sponge off the water and place back in the drying oven of the platemaker for 5-10 minutes. We also suggest, alternatively, a hair dryer to warm the plate and make it more pliable (placing your plate in a box and blowing the hair dryer into the box will keep the warm air more contained).
3. After the plate warms and starts to uncurl, place the plate in its bag and set a heavy object on it to keep the shape.
This should help your plates relax so you can adhere them to your base for additional print runs. Some warnings for you – take care to avoid putting your hair dryer too close to the plates and be patient as warming the plates takes time. And watch that you don’t handle them too roughly after the wash and during drying so your relief images don’t chip.
Store your plates flat. One last tip, you may have to check your adhesive backing to determine if it needs to be re-applied to the back of your plate for a secure hold on your base.
If you have some storage and uncurling tips, tell us about them so we can share. It’s great when we can all learn from each other!
If my plates are starting to curl I place them in a zip lock bag with a wet paper towel over night. The next day they’re much more pliable and ready to print! Some of my plates are more prone to curling than others, those I just always store in the ziplock with a towel if I use them multiple times.
Great idea — thanks Shayna!
I believe the curling is made worse if the plate is left exposed to fluorescent light. Generally I simply put it in the drying rack of the photopolymer platemaker for 4 minutes and the warmth will make it more pliable. The I simply place it on the magnetic base and leave it there overnight or use it if I need.