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Stamp Collecting : Preserving and Conserving Your Collection : Vinyl Enclosures

Vinyl Enclosures

Philatelists are one of the largest collecting groups worldwide and numerous companies are in the business of supplying them with products for the display and storage of their prized collections.

Consumers should expect to pay a fair price for what they purchase. But do they always know what are they purchasing? The word "archival" is one of those terms, like "low-fat," that seems to sell products. With no consumer regulations to control or define what constitutes an archival product, consumers must educate themselves.

Producers and sales representatives can give the chemical breakdown of the materials and goods they are offering. If you are interested in using a plastic material for housing or mounting your collection, ask if it is polyester, polyethylene, polypropylene or vinyl. Ask if the product contains PVC. If you aren't able to receive concise answers, consider looking elsewhere.

Clear enclosures for your collections should be made from an inert, clear material. Inert means chemically stable—it will not react chemically with other materials (such as your collection). One of my favorite ads from philatelic catalogs reads 'safe vinyl,' inferring that it will not react with your objects! Vinyl is neither safe nor stable. Why? Because it is not inert. Vinyl is "a univalent chemical radical (CH_CH)"—by definition "any of various compounds, containing this group, typically highly reactive, easily polymerized and used as basis material for plastics."

Highly reactive means that any enclosure made with a vinyl compound will interact with the material with which it comes in contact. This interaction/reaction will, over time, cause permanent damage to that material. A vinyl enclosure may be fine for the short-term display of material, but it should NEVER be used for long-term storage of any collection material.

Fortunately, there are alternatives. Polyester, including Mylar®, is a very clear, fairly rigid material that is chemically inert. This material is used by the National Postal Museum for exhibitions and storage of the collections. It shows well in albums and other types of displays.

Polyethylene is a softer, clear inert plastic often used in sleeves for photographs or other display mounts. Polyethylene is a plastic and often comes in rolls or sheets. The Museum uses this material to cover larger objects in storage to protect them from dust.

Polypropylene is another inert plastic that is used in sleeve pages for photographs, similar to the polyethylene. Both of these materials are often labeled as PVC free, meaning that they contain no polyvinyl chloride and will not emit hydrochloric acid as they deteriorate.

The world of plastic products can be confusing. Before selecting a plastic enclosure, ask for some samples or order a small quantity. Experiment. Find the product that will work best with your personal collecting needs. Once you have found a reliable source for display and storage products, the rewards will be well worth your time and effort.


Conservation Advice: State Library of Victoria, Melbourne, Victoria, Australia



Guidelines for Caring for works on paper














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