Subject: Adhesives for bookplates
In 1986 I asked Merrily Smith the same question Brian McKinney asked Aug. 14: What is the best adhesive to be used on bookplates? She said it should not have a very low pH; it should not affect adjoining materials, as by oozing or turning brown; and it should stay adhered. This lets out most of the adhesives on the market, and all pressure-sensitive adhesives. Most PVAs become more acidic with age, though Jade 403 changed very little in the tests done by the CCI in the late '80s. Jade 403's formula must have changed, though, because conservators have been complaining about a bad odor, and it looks like they are switching to Elvace 40-704, produced by Reichhold. Whatever PVA is used, it can be applied by hand or machine. If done by hand, it goes faster to put the glue on a piece of glass or something, lay the bookplate down on it and rub it down, then lift with a scalpel and lay it on the book. If done by machine, a little glue machine, just big enough for the purpose, makes it go a lot faster. Paste meets all the criteria, if you use the same kind conservators use. It takes more skill to use, though, because it is wetter than PVA. Methyl cellulose is ideal in all regards except that it does not form a very strong adhesive bond. It is sometimes mixed with other adhesives that do. Don't use peel & stick bookplates. There is no pressure sensitive adhesive that is entirely without fault, and if a pressure-sensitive label is not made especially for long-term use, you can be sure it will have not one or two but several faults, which it will manifest within just a few years. These faults are, with the worst of the lot, to turn brown, to stain the material it is on, and to fall off (a la Scotch tape), leaving behind a stubborn residue (like masking tape); or, with the better ones that use acrylic adhesives, merely to ooze into the paper, darkening it and making it translucent, to make some inks blur and spread under the tape, sometimes to ooze out from under the label or whatever it is on, causing the opposing page to stick to it, also dust and dirt to collect on the ooze. In time it cross-links, becoming very hard even for an expert to remove. Don't use YES Stikflat Glue either. It is advertised as being acid-free, which it is, but it deteriorates nevertheless, staining and damaging the material it has been used on. Peter Waters says it should be called NO Stikflat Glue. **** Moderator's comments: To send mail to Ellen McCrady, put FORWARD: Ellen McCrady at the top of your message and mail it to whenry [at] lindy__stanford__edu *** Conservation DistList Instance 6:17 Distributed: Saturday, August 29, 1992 Message Id: cdl-6-17-001 ***Received on Saturday, 22 August, 1992