Subject: Paint for microfilm cabinets
In response to the inquiry about paint for microfilm cabinets, several questions should be asked first. The first relates to the cause of the rust. Is it simply a humid environment or perhaps the presence of Kalvar film? If Kalvar, the cabinet will continue to rust until the Kalvar is removed and replaced. Secondly, are the films to be stored silver gelatin, vesicular, or diazo? If the latter two, there is less concern about off-gassing. Lastly, what other types of collections are stored in the vicinity that might be affected by off-gassing. That having been said, I pass along the following paint specification that the conservation department of the Minnesota Historical Society uses when purchasing collections storage cabinets and shelving. It was also used to evaluate paint proposed by the architect for walls, ceilings, and floors in its' new facility. 1. The film forming resin shall be a stable, inert material such as acrylic, polyester, or epoxy. Examples of acceptable resins are water reducible acrylic, epoxy and epoxy/polyurethane, and powder coatings of polyester or epoxy resins. No PVA shall be contained in the formulation. Also not acceptable are alkyd or vinyl toluated alkyd resin finishes. (note: alkyds have been identified as affecting silver emulsion photographic emulsions. 2. The formulation shall contain no long chain drying oils. 3. Upon receipt, the product should not be off-gassing solvents or other volatile substances. The product shall be odor free indicating complete absence of residual solvents. The test procedure for complete cure shall be provided upon request by the manufacturer or distributor. 4. The paint film shall have no free, unreacted radicals remaining. 5. The formulation (film forming resin or pigment) shall not include any sulphur compounds. 6. Biocides such as formaldehyde shall not be included in the formulation. The manufacturer of the cabinets usually will not be able to answer these questions and you will need to get the name of the paint manufacturer. Eventually, you will get to a chemist at the paint company who will be able to answer your questions. With the increasing use of powder coat finishes, this task is getting easier. If a manufacturer does not want to cooperate and get the information for you, go to a different cabinet company. *** Conservation DistList Instance 8:2 Distributed: Friday, June 17, 1994 Message Id: cdl-8-2-001 ***Received on Wednesday, 15 June, 1994