What are the noticeable effects of acidity on drawings?

Question

I've seen paper proudly proclaim it is acid-free, and heard that one should avoid storing artwork against acidic surfaces or even TOUCHING the paper with one's fingers during the drawing process, blending with tissue paper instead of fingers. This last one especially bothers me, since I often use my fingers for blending.

What happens to a drawing that is exposed to acidic paper and skin? Does it get blotchy? Do the colors change? Can anyone provide a before-and-after image of a drawing that has changed due to acidity?

Answer 1

You do have a small amount of acid in the oil of your skin, but not alot on your hands and during normal handling it evaporates anyway. Your biggest problem isn't the paper or handling but the ink. Charcoals, pastels, and graphites are all harmless but unless you see the little AP circle stamp on the pen or ink bottle I'd be careful. India and sumi inks are usually fine. Most normal writing pens have strongly acidic ink, thats why drawing pens are expensive. You get what you pay for. Addressing paper, most papers have a little bit of acid in them left over from the bonding process. If your going for archivial quality, your best bet is buying handmade paper or better yet learning how you make it yourself since it uses water that you can control. Its a messy process and takes alot of time, but alot print makers and illistrators swear by it. A simple test you can do is get a cheap notepad and do some test lines with different pens. Put a 1-5lb. weight on top of it and set it aside for a week. If its acidic, you'll see a yellowish imprint on the oposite side.

Answer 2

you get a hole in it if theres acid.