articles: Kodak research: Print Storage
an excerpt from Kodak's "Storage and Care of KODAK Photographic Materials - Before and After Processing"

Photographic prints are everywhere: in wallets, on walls, in albums, on desktops. Prints are popular because you can view them anytime without special equipment, and because--in most cases--you can replace them if they fade or become damaged. But when you don't have the original negative to reprint, care of the print becomes very important. Most guidelines for storing other photographic products also apply to prints. The dyes and emulsion layers in color papers make storage of color prints more critical than that of black-and-white prints.

Select the print material that best suits your needs. Many factors--light, heat, humidity, and atmospheric contaminants--can affect the life of a print. Even under the best conditions, a print on continuous display is likely to change in time. When prints are intended for display, store the original negatives or slides properly so that you can make new prints if the display prints begin to fade.

Because KODAK PROFESSIONAL and KODAK EKTACOLOR Papers have excellent dye stability, you can expect color prints made on these papers to keep for a long time--many decades for prints on display under typical home lighting, for example. For applications that require physical durability, use KODAK PROFESSIONAL DURAFLEX Print Material; this material has the same image-stability characteristics as Kodak color negative papers. You can expect prints made on KODAK EKTACHROME Papers and Materials to have a long life if you view and store them as described in the following sections.

Provide a cool, dry, uncontaminated storage place. If you have prints that you don't expect to display or that you want to store for a long time before you display them, you may want to leave them unmounted. Unmounted prints occupy less space and involve fewer materials that can harm the images.

Avoid storing prints in the original cardboard box or package. Packaging material that is suitable for unexposed sensitized materials may not be inert to processed materials. Use archivally safe boxes or envelopes.

The best storage conditions for color prints are the same as those for most other photographic products. Store prints in the dark at 75°F (24°C) or lower and at 30- to 50-percent relative humidity.

For long-term storage, keep prints at lower temperatures. If you are going to store small prints in a freezer at 0°F (-18°C), condition the prints at room temperature and at 25- to 30-percent RH before sealing them in moistureproof storage envelopes. Protect prints that are larger than 8 x 10 inches (20 x 25 cm) from moisture by using three layers of aluminum foil and sealing the folds and seams with moistureproof tape such as freezer tape or vinyl electrical tape; don't use "friction tape." Be sure that the storage area and the conditioning room are free of fumes that might be harmful to prints. If you store several prints in one package, interleave them with acid-free paper.

Store prints in albums for convenient access. A less elaborate way to keep prints, and one that combines ready access with good long-term storage conditions, is in a photo album. To get the best results from storage in an album, keep it in a place where the temperature and humidity aren't excessive.

Caution
Fumes from mothballs, mildew inhibitors, wood preservatives, paints, varnishes, and wood glues can contaminate drawers and harm photographic materials. Therefore, open bookshelves may be a better place to store albums and prints.

Because the prints are in direct contact with the pages of a photo album, make sure that the materials in the album are suitable for long-term storage of photographs. Check these items--cover, pages, plastic sleeves, mounting corners or hinges, and ink used for identification.

Mounting and displaying prints. The issue of whether or not to mount a print remains controversial. On the one hand, most custodians of photographic materials argue that photographic artifacts, vintage prints, or contemporary prints of considerable value should never be mounted. They abide by a principle of conservation that says original artwork must be preserved with absolutely no alterations. Mounting a valuable print can actually decrease its market value and jeopardize its authenticity. Also, older photographs may have stamps of past owners (e.g., museums or other institutions), size markings for use in publication (linking the print with a specific printed publication), or other important markings on the base side. To preserve important images, it may be wise to limit access to them, view them for only short periods, and store them archivally.

On the other hand, mounting photographic prints provides several advantages. Mounting provides rigidity, prevents wrinkling, and gives a degree of physical protection. Prints are usually mounted when they are being prepared for sale or display. Mounting is especially suited to contemporary or newly made prints when the original negative is kept in safe storage. Many identical prints can be made at the same time and the extras left unmounted for easier archival storage. If the negative or other original is not available, it is a good idea to make copies for mounting and display, and keep the original print in safe storage.

Just as you should select a print material that's appropriate for your needs, you should select an appropriate mounting material. When you mount prints of little value for short-term display, you do not need to use archival mounting materials and methods. However, when your objective is long-term keeping, the mount must be of archival quality. Long-term or conservation mounting requires that the procedure be reversible; that is, you must be able to remove the print from the mounting materials with no damage to the print. Therefore, you should always record on the back of the mount what mounting materials you used. You can use a No. 0 or No. 1 lead pencil for marking the mount, but do not use excessive pressure.

Mounting board is the most commonly used material for mounting photographs. Most mounting boards designed for photographic use are acid-free and pH-buffered. (Use materials that are not acid-free and pH-buffered only for short-term mounting.) One method of long-term mounting involves attaching the print to conservation board with acid-free paper hinges or corner pockets. These materials are often used with a window mat placed over the photograph. Interleave mounted prints with acid-free paper when you store them.

Two types of dry-mounting tissue are recognized by American National Standard (ANSI) PH4.21-1979, Specification for Thermally Activated Dry-Mounting Tissue for Mounting Photographs. Type 1 tissue is permanent--you cannot remove the print from the mounting board without damaging the print or the board. Type 2 is a detachable type of tissue that allows you to remove the print from the mounting board by reheating the mounted print. KODAK Dry Mounting Tissue, Type 2, is an adhesive for mounting color or black-and-white prints made on RC or fiber-base papers with a platen temperature of 180 to 210°F (82 to 99°C). You can use some dry-mounting tissue for hot- or cold-mounting techniques. However, most dry-mounting tissue that is considered to be archival (at the time of this publication), is made for hot mounting. Starch paste and polyvinyl acetate (PVA) adhesive are satisfactory for short-term applications. Never use rubber cement; its high sulfur content will eventually cause chemical stains to form on prints.

Examination of old photographs shows that mounts that are considerably larger than the prints offer some protection from deterioration due to chemical penetration at the print edges. When you mount prints, use a large enough mounting board to leave borders of approximately 3 inches (8 cm) at the top and sides of the print, and about 3 1/2 inches (9 cm) at the bottom. If mounts become damaged, you can trim the edges.

Protecting the surface of a print will help prolong its life. A hinged overlay or window mat that covers the print and mount offers some protection from atmospheric gases or materials that might come into contact with the print while it's being stored or transported. Protect prints that you plan to handle frequently with a sheet or sleeve of transparent material. Plastics suitable for this purpose include cellulose acetate and polyethylene terephthalate (polyester) without surface coating. You can protect framed prints with a sheet of glass or rigid plastic such as Plexiglas UF-3, which absorbs ultraviolet radiation. Always leave a slight separation between the print and the glass or plastic.

Color prints are often lacquered to enhance their appearance; to protect them from soiling, scratching, and abrasion; or to provide a surface for pencil retouching. Many different lacquers are available, and manufacturers change formulas frequently. Therefore, it is difficult to say whether or not a particular lacquer will adversely affect long-term image stability. Because certain lacquer ingredients can accelerate dye fading in prints, it's best not to use a lacquer if you intend to store a print for a long time.

You can't always display prints in a way that promotes long-term keeping. The best practice is to display them under subdued incandescent illumination, such as normal household lighting. Place them as far from the light source as possible and away from direct sunlight. Avoid temperatures above 75°F (24°C), relative humidities above 50 percent, and damaging chemicals and fumes. For important collections, you can use gas-monitoring devices to measure the concentrations of corrosive chemical gases. One manufacturer of gas-monitoring equipment is National Draeger, Incorporated, P.O. Box 120, 101 Technology Drive, Pittsburgh, PA 15230. If you can't avoid less-than-ideal display conditions, make several identical prints from your negative or transparency. Store the extras in a cool, dry, dark place. The extras will outlast the display print, and you can use them as replacements.

All text and images unless otherwise indicated are Copyright © 1999 - 2001 by Studio Braun.