Century® Archival Products are recognized as the "Quality" choice for archival boxes.
The information on this page allows you to learn about the different facets to preservation and that there is a distinct difference between saying "acid free" or "archival quality" and being "acid free" or "archival quality." Learn and compare why Century® Archival Products are the preferred choice of those interested in both preservation and presentation.
Midnight Black Barrier Lining
- Acid Free
Black Outer Cover
- Leather like "Mission" Embossed Textured Fabric
- Acrylic Coated
- Moisture Resistant
- Meets ANSI L29-1977 Standards
- Conforms to NASTA Standards
- Strong 100 point Paperboard
- All Corners Metal Edged
- Spines - Triple Strength Reinforced Cloth Hinges
- Century Specified PH Neutral Adhesives
- Glues - PH Neutral
The use of "acid-free" is probably the most misunderstood concept in preservation. For preservation purposes, the use of "acid-free" and "archival-quality" is meaningless. These terms are used to communicate to the market users of the importance of these attributes and that they will purchase the products on the strength of their use.
Many products are marked acid-free. However, they are made of wood pulp. While this paper material is PH neutral in its just-manufactured state if it has not been chemically processed to remove lignin or other potential pollutants nor has been alkalized by the addition of a buffer, it will acidify quite rapidly given warm and/or humid storage conditions. Thus while new boxes of this type will provide an initial neutral environment, it is only because not enough time has passed to develop acids. After a passage to time, do not be surprised to finding a ph 5.0. In reality, these materials are not for true archival use but intended for temporary storage of material on a retention schedule.
If you want true "archival-quality" boxes you must look for material described as "lignin-free" (another misnomer) or low lignin, "buffered" (often ph approximately 8.5), and "alkaline reserve" (often 2% to 3%). Century® Archival Products provides an environment with a ph of 8.0. A lignin/acid/sulfur-free liner buffered with 3% calcium carbonate. You will not find a better archival box.
As information, a few things that should not be stored in buffered enclosures are hand-colored materials (such as water colors or maps), blueprints, and cyanotypes. The coloring agents may react with the buffering chemicals to discolor. For these categories use "ph neutral" (approximately 7.0) storage materials or stable plastics. For albumen prints, the conservative choice is also neutral storage although it is thought that if you have dry, stable storage conditions, buffered enclosures should perform well.
Since acidity is the primary concern in the aging of paper, storage materials that are constructed of acid free materials will enhance preservation by ensuring that no migration of acid from the storage container itself to the stored item will occur. An important external source of potential acid will be eliminated. The degree of acidity is measured by a pH factor. Values from 0 to 7 are considered to be acidic, while those measuring from 7 to 14 are termed alkaline. Currently, a Cold Extraction Method is used by some of our suppliers to test materials and certify that they are acid free. To further reduce the likelihood that the storage boxes will deteriorate and produce harmful by-products, alum and rosin are eliminated from the manufacturing process of the board and paper and wood pulps used have a reducible sulfur content of less than .0008%.
The Century® line of archival storage products provides an additional element to help prevent premature deterioration. That element is a barrier of Permalife brand paper lining the interior of each box. The lining is sulfur free, again decreasing the likelihood of the formation of sulfuric acid from moisture inherent in the box or the stored item. The lining is also lignin free, which lowers the possibility of acid formation, which could destroy photographic images, film, or other stored items. Furthermore, the lining is buffered with calcium carbonate, which acts as an alkaline reserve to neutralize acidic degradation components. This slows the aging process and keeps the destructive by-products of aging from catalyzing further reactions. According to the manufacturer of the Permalife brand paper, the liner has a life expectancy of 300 years.
To protect stored items from more generalized environmental hazards, Century®boxes are covered with an acrylic impregnated woven fabric that is both moisture and vermin resistant. The boxes are designed with a clamshell structure that shields enclosures from dust, as well.
Some Century® boxes include polypropylene sleeves with acid free/lignin free black insert sheets for storage of photographs. The supplier asserts that the inserts pass the Photographic Activity Test (P.A.T.). Additionally, our acid free microfilm boxes have been tested in the past using this method to evaluate the quality of photographic enclosure materials. Briefly described, the P.A.T. is a process in which tested materials are incubated in high temperature and humidity in contact with specialized photographic detectors. The detector identity damage related to fade (interactions with silver images) and stain (interactions with the gelatin or binder in the photograph). To pass the mottling beyond specific criterion levels. By using materials, which pass the P.A.T., our products provide additional protection within the specialized needs of the photographic art market.