This is all about providing the best possible environment for the cel collection -again-. I think the biggest problem is conservation knowledge, when I started collecting in 2005 (15 years ago!), the collection was small and the cel community had some general guidance but it was mostly geared to what’s economical and yet still somewhat “archival” practices. It went a little like this, buy a cel book like an Itoya, buy cel bags and don’t seal or put a cut in the cel bag so it can breathe. Avoid light and avoid undue pressure and bending of the cel. Try to keep it in a cool area. Over the years people started adding, add Microchamber paper (jury is still out on Microchamber paper due to it’s effect on plasticizer but it does help with gas emitted by the cel). Nothing truly bad with that advice but I believe over time we truly get to see the effects of these advise when the cels are now 25 years old. I own cels that are 50 years old too like my Daimos and Voltes V cel collection.
So what’s happened? Well cels are mixed media, you have cellulose acetate and you have paint and some xerox ink etc. I am of the opinion that preserving cellulose acetate is one of the most important thing because otherwise the entire cel deteriorates like the Disney cels we see today that are cracked, warped and shrinking. The cel acetate stored in room temperature with normal humidity like 70% will only last 50 years which explains why some of the cels today for shows in the 90s start having vinegar syndrome. It’s difficult to know the storage condition of these cels before you get them so some of them may have degraded but you can’t see that when you first get them. But eventually all cels will succumb to their impermanence and my hope is to be able to preserve them in pretty good shape in my lifetime. After I’m dead it won’t matter but I hope whoever gets them, continues to care for them, especially my Saitou and Shinsengumi cel collection.
So what are somewhat ideal conditions for private collections? Well unfortunately there is no guidance for every facet but currently the Getty and Disney Research Labs are trying to do that work but today we have to be guided by best practices in other media that is similar in composition to a cel. The closest is for photographs and film. I’ve decided on a few things:
- Separate paper products from cel products. Paper products have acid in them and cel produce acetic acid as a gas. These mix and produce more chemical reactions that can be auto-catalytic.
- Remove cels from polypropolene or any poly bags even if inert or archival. My experience is that these pucker over the years which indicate a chemical reaction.
- Use archival or better yet museum grade materials in housing your artwork and if using archival, know that there is a finite life on those i.e. Black archival inserts eventually has to be replaced every few years
- Keep in mind the usual advise of not exposing to too much light, not bending the cel or putting too much presure on the cel when deciding on storage. Try not to handle the cel too much.
- Keep cels in the following temperature 55 to 65 Fahrenheit with a relative humidity of 40%-55% as a preventative measure to retard the degradation of cels. Again all cels will end up with vinegar syndrome and “die” but it’s up to you whether this is in your lifetime or if the cel will survive 100+ years in addition to your lifetime.
- Inspect the condition of your collection every 3 to 6 months. Not 1 year or more, although the usual advise is once a year.
- If any cel shows signs of vinegar syndrome (VS), quarantine those cels or send them to a conservator to deal with the VS. If you can’t send to a conservator right away, they may do well in cold storage which is 30-40 Fahrenheit but careful with humidity or getting the cel wet, 20% or lower humidity is not recommended due to paint cracking.
An excellent paper can be found done by the IPI and I encourage all cel collectors to know this guide well even if it is not for animation cels specifically, most anime cels are made up of the same material. IPI Storage Guide for Acetate Film