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Please refer to the list of frequently asked questions.

What is the effect of deacidification treatment?

A. Library of Congress in Washington, Institute of Paper Science and Technology (IPST) in Atlanta, Image Permanence Institute in Rochester, The Institut Royal du Patrimoine Artistique in Belgium, TNO Center for Paper and Board Research in the Netherlands, Switzerland Berner Fachhochschule, and the American Philatelic Society, have independently conducted verification experiments on processed paper materials and comparison experiments with unprocessed samples. These forced deterioration experiments have shown that the bookkeeper deacidification process has the effect of extending the useful life of paper materials by at least 3-5 times. Although forced deterioration does not always accurately reproduce the results of natural deterioration, the life-prolonging effect of paper materials seems to be greater than expected in the forced deterioration test due to the nature of the test.

What kind of material can be processed?

A. Bookkeeper deacidification is suitable for all forms of paper materials such as bound and non-bound documents, printed and handwritten documents, newspapers, books, letters, envelopes, stamps, paper products, pamphlets, and maps and prints. .. Since no solvent is used in the processing process, it does not damage adhesives, bindings, leather, plastics, metals, fibers, etc., and it does not scatter, bleed, or dissolve ink.

The bookkeeper deacidification process does not place a heavy burden on the material, but the paper material to be processed must be stable and able to withstand careful handling. Materials that are inadequately repaired or are too fragile to handle are not suitable for this process.

Can you process photos etc.?

A. The Image Permanence Institute has tested photographic material in contact with bookkeeper-treated paper and has confirmed that it safely meets the requirements of the Photographic Activity Test (PAT). However, the bookkeeper is not intended to store photos and has no effect on photos. In addition, the bookkeeper does not adversely affect the photos, and the photos can be safely stored with the processed paper materials.

Is it safe for coloring and ink?

A. The bookkeeper deacidification process is solvent-free and water-free. Independent tests on hundreds of ink and paper samples prior to 1870 did not detect ink or tinting that was dissolved or smeared by the bookkeeper.
In rare cases, the change in pH from acid to alkali may affect the shade of color. However, even coloring that is sensitive to changes in pH is hardly affected unless the paper gets wet in water or a humid environment. Please do not use the bookkeeper deacidification process on "blueprints" or other similar materials that are affected by elevated pH.

Is it possible to prevent the browning of paper?

A. No, papers like newspapers contain chemical impurities that are affected by light and oxygen. These tend to turn brown over time. The treatment does not accelerate browning (yellowing).

Is there a possibility of alkaline hydrolysis due to increased pH?

A. There is none. The maximum achievable pH when using magnesium oxide is 10.4, which is well below the value required to embrittle the paper. Alkaline hydrolysis occurs at much higher pH values and at temperatures well above room temperature in the presence of excess water (liquid).

Is it dangerous?

A. The bookkeeper deacidification process is harmless, non-toxic and non-flammable. The deacidifying agent is odorless and dry, can be used in normally ventilated spaces and has no special exhaust requirements.


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