cleaning my polymer plates

California Wash, Scrub-a-Dub, or most water-miscible press washes.

You don’t need very much solvent on a rag to clean a plate. Just give them a wipe down and stick them back on their backing material. Make sure to store them as they arrived from the platemakers- in the bag and sandwiched between the two pieces of cardboard.

Daniel Morris
The Arm Letterpress
Brooklyn, NY

Thanks guys!

I use POSCO rubber plate and type wash. Its designed to evaporate quickly, unlike roller wash, so it doesn’t leave an oily residue.
James Shanley
Bdesigns

agreed

I find putting a thick coating of crisco or lard on my plates while storing them helps retain moisture and printing surface. Just make sure you enclose each one in a zip-lock bag. Make sure you get zip lock brand because it tends to be more resilient than glad ware bags.

Ewwwh!

Ewwh! indeed.

I’m not sure you want to put hydrophilics on your plates, much less clean your presses with them (another story). You can’t really re-invent chemistry, and just because some vegetable oil is in your kitchen, doesn’t mean it is somehow safer or more appropriate to use in mechanical applications.

Photopolymers are attacked by ozone. There is an engineering term for this: ozone attack. Huh! Carbon dioxide and antiozonants are the remedy. Blow into your zip lock bag before you lock it up (you inhale oxygen, exhale carbon dioxide/moisture, Christ) or use a protective spray like ArmorAll if you really need to preserve them.

Photopolymer plates also continue the photopolymerization process with further exposure to UV light. Use preventive measures in this regard as well. Like, keep them out of any light source. Note that once you have editioned a plate it has been exposed for some many hours to natural or artificial light and it is already a ways down the road to its natural end).

Once a photopolymer plate has lost its tack, it’s just a piece of brittle plastic without any printing qualities whatsoever.

Gerald
http://BielerPress.blogspot.com

I’ve got to agree with Gerald. His comment is so to the point that it needs repeating:

“I’m not sure you want to put hydrophilics on your plates, much less clean your presses with them (another story). You can’t really re-invent chemistry, and just because some vegetable oil is in your kitchen, doesn’t mean it is somehow safer or more appropriate to use in mechanical applications.”

Now…. about preserving PP plates: While you can store them for a while, they are not really well suited toward long-term storage, or multiple re-uses. Metal cuts are far better in that regard. If you DO want to keep them, follow Gerald’s advice and keep them away from the air and UV light.

avivona

The only solvents/inks that have been indicated as detrimental to photopolymer plate health and longevity are those containing acetates.

As James mentioned, specific cleaners are best, but his recommended POSCO is a bit hard to find. Most of the plate cleaners that I have used, such as Aled, are no longer on the market. But you do need a fast dryer if you are cleaning the plate during presswork. Otherwise ink and debris such as paper dust and rag fiber will cause problems. Mainly because the relief of photopolymer plates is tacky and will retain these materials. They will attract further ink into the relief areas and start to print, thus causing your imaging to become fuzzy. I would recommend that folks not ask for proofs from a plate processor for this reason, as the plates come to you with rag lint, and residual ink, already included at no extra charge!

Substitute inexpensive fast dryers like 100% Isopropyl Alcohol (printer’s alcohol) or Coleman Lantern Fuel (white gas) work well if used in moderation. Note: these are highly flammable and need special storage containers. There are special lint free cloths on the market (medical, aerospace) that I suggest for cleaning plates. Combined with a soft toothbrush, such as those used on gums, as well as a spray of compressed air, will help quite a bit.

In regard to storage, mainly keep the plates away from light and heat as well as ozone, the primary cause of plate deterioration. Ozone is generated by electrical motors, lighting, etc. It is also more common in the local atmosphere during the summer months. Combined with high temperatures it will deteriorate the plates quickly, and in sever conditions, cause cracking.

Used plates should be stored flat in paper envelopes, or saran wrap, or black plastic, or as mentioned, in zip lock bags. But it is far better to regenerate from the original negatives than to re-use an older plate, as you cannot successfully halt the degenerative process.

Gerald
http://BielerPress.blogspot.com