[Art Collector’s Etiquette] How to Prevent “Mold” and “Stains” That Quietly Progress Inside a Frame

The Truth Inside a Frame

I have a habit of returning to my parents’ home every New Year.
It’s a lively, boisterous family tradition of relatives, with New Year’s money, delicious food, and gifts flying around.

Amid all that, I came across a scene where an artwork in the living room — one I hadn’t paid much attention to as a child — suddenly grew radiant in presence. When I checked with my parent, its owner, I got a “you can take it home,” and, delighted, received it…

What I received was “a print by a certain master.” Made in 1974, it’s a work over 40 years old.
Apparently it was a piece the artist, short on money at the time, had sold by hand himself.

A while after receiving it, curious, I decided to open the back of the frame to look at the work, and opened the frame held shut with turn-buttons.

Wh-what is this…!?

Brown “stains” spread all over — the kind that might get you scolded by Chiko-chan (a Japanese TV character) with “Don’t live your life half-asleep!”

Nothing showed on the front of the work at all, so I hadn’t noticed until I opened the frame.

Why Do Stains Form?

With the rainy season and typhoons, Japan is a country with a troubling climate, full of high-humidity periods.
In the case of the spotty brown stains I saw this time, in addition to the influence of components like resin and lignin from the frame’s backing wood, mold-like stains occurring through oxidation caused by humidity changes — that’s the likely mechanism.
The acrylic (glass) on the front mainly serves to counter ultraviolet (UV) rays, and I think you can address that to some degree by avoiding direct sunlight and choosing materials with UV-cutting properties.
On the other hand, the back of the frame uses wood, which has limits in coping with environmental changes. A frame closed tight with no gaps is one thing, but conditions inside a frame with even a slight gap can be considered harsh.The conditions inside a frame are influenced overwhelmingly more from the back than from the front — or so it’s said. Indeed, the “location of the stains” this time was on the back of the work.
Among artworks, those using paper have a support weak to environmental change, so the chance of degradation over long stretches of time is higher.

It’s not that “it’s protected because it’s in a frame”; you must stay cautious even when the work is inside a frame — that’s the point.

What the Framing Shop Did

What could I do to counter this situation…?
Leave it as is and it would only worsen — mightn’t the stains even spread to the work side, so far unaffected?
So I took the framed work in person and consulted a framing shop I know.

Please see the diagram below.
Proper framing is recommended to protect the work through a flow like this.

In the work I own, in the place where a “neutral intermediate material” should be inserted there was a single sheet of “cardboard,” and in the place for the “protective material” (the Super Barrier Sheet in the diagram below) meant to block influence from the backing board, nothing was inserted at all.

So I asked the framing shop and had them do a “neutral paper + Super Barrier Sheet” treatment (see the photo below).
This came to “about ¥800” (materials and prices likely vary by shop).

The SUPER BARRIER SHEET is from “muse,” a maker that also sells “FILMOPLAST,” which I introduced before. With a track record of selling various goods and items for artworks, it’s a trustworthy maker.

Both neutral paper and the Super Barrier Sheet are, in thickness, as thin as paper, so you can insert them without changing your current frame.

This treatment was done to “prevent further progression.”
There are also restoration-oriented treatments, such as “removing the stains” or “bleaching the stains.” The framing shop I visited didn’t handle these. If I get the chance, I’d like to report on that separately.