Archival plastic enclosures can be made from polyester, polypropylene or polyethylene.
Polyester is the most inert of the three, it can generate static electricity which attracts dust and is more expensive.
Polypropylene is a stiff, high clarity, and chemically stable plastic.
Polyethylene is also chemically stable and although transparent in its low density form, is not as clear as polypropylene.
We suggest using our Permapaque opaque paint markers. Chisel point for wider coverage
When storage materials are “buffered” it means an alkaline substance has been added to counteract the acids that may form in the future and to help absorb acids from artifacts. Alkaline-buffered storage materials usually have a pH of between 7.5 and 9. Most objects can be safely housed in unbuffered neutral pH material (with some exceptions). When in doubt about the type of enclosure or container to use, an unbuffered neutral pH enclosure is recommended. Read more about it and see a list of what items should be stored using buffered or unbuffered materials here- Buffered And Unbuffered Storage Materials.
The Photographic Activity Test (PAT) is a worldwide standard (ISO Standard 14523) for archival quality in photographic enclosures. Developed by Image Permanence Institute in Rochester NY, this test predicts possible interactions between photographic images and the enclosures in which they are stored. The PAT is also used to test the components of enclosures, such as adhesives, inks, paints, labels, and tapes. The test involves incubating materials in temperature- and humidity-controlled chambers to simulate aging and takes from four to six weeks. After incubation and sample evaluation, a final report is provided.For more information visit their website at www.imagepermanenceinstitute.com
An acid-free and lignin-free paper or board is a purified material that will not break down over time and become acidic. A paper or board that is only acid-free and still has lignin content will become acidic. Lignin is an organic substance found in wood pulp. The lignin breaks down into acid and will yellow or discolor the paper or board and whatever else contacts the paper or board.
Glassine envelopes are not archival quality and should not be used for long-term storage. You should avoid normal glassine. Biaxially-oriented polypropylene (BOPP) can be identified chiefly by its superior clarity and “crinkly” or crisp feel. BOPP is growing in popularity among manufacturers of archival products because of the ability to make a nice presentation sleeve as well as being safe for long-term storage.
PVC or Polyvinyl chlorides are very harmful to photographic material. Any plastic formulated from PVC should be avoided and will cause rapid image degradation. PVC contains and transfers plasticizers, salts, and hydrochloric acid to print emulsion, which is very harmful to photographic material.
For almost thirty years, Print File has manufactured negative preservers from polyethylene, an archival material proven safe for maximum long-term storage. We use polyethylene since the alternative polypropylene, creates a greater static charge, which consequently attracts more dirt and dust to the negative. In addition, dust and scratches are more noticeable on enlarged negatives; therefore, it is imperative that the conditions to reduce dust and scratches be controlled as much as possible. We optimize these conditions by manufacturing our negative preservers from polyethylene.
We believe the presentation of your valuable photographs requires the clearest and most transparent archival preserver available. Print File’s superior polypropylene offers this clarity whereas polyethylene is more translucent. Slides are protected from rubbing against the film by the mounts and are not subject to the same static problems as negatives. Furthermore, photographs are not customarily reproduced from the print and the consequences of dust on the photographs are less critical to the final outcome of your preserved image.
