Preservator Question

Tim Hayes.

SGF, Supreme Grumble Framer
Aug 31, 2001
I was told by a conservator that silk is acidic by nature. Preservator if you are around please comment on this.

Tim Hayes
The word "Silk" refers to the excrement that comes from a "Silk" worm. The thread itself is not usually the problem, except for the laperdopus which isn't used for cloth. It is the "other stuff" that is a problem.
The "Silk" is spun, dyed, and woven into many different clothes.
If in doubt, go to a good mom & pop drugstore (we're boycotting the BBs) and get a bottle of distilled water, and litmus paper.
Place the cloth on a piece of rag mat board and drop a few drops of the distilled water onto the cloth untill you make a wet-spot (no giggling please) about the size of a quarter. Let stand about 15-20 minutes then with CLEAN tweezers, lay a litmus strip on the wet-spot and gently jam it into the spot untill wet/damp. If it changes color, compare to the chart that came with the litmus and you will know for sure about THAT piece of cloth.

Personally, I have yet to find a piece of silk that was more than 1 point off center.
For my age, that is pretty darn neutral.

Silk is a protein and, like all proteins, is slightly acidic and likes a neutral or very slightly acid environment - like between ph 6 -7.

Neutral, rather than alkaline buffered contact materials (tissue, matboard) are recommended for protein materials (gelatin, wool, silk, leather...).

"gently jam it into the spot"

This makes me laugh. It sounds like I was the one posting.
As Rebecca noted, the silk, itself is not very
acidic, but the things that added to it to make
it shine and hang can represent a problem. Keeping the silk away from the art with
a layer of mat board is a good idea, as it is
with most fabrics.