Library of Congress Information Bulletin Vol. 41, No. 15, April 9, 1982

Library Licensed to Make Deacidification Solution

The Library of Congress has taken a nonexclusive, royalty bearing license, effective October 1, 1981, to make and use nonaqueous deacidification solutions for materials in the Library’s custody and in facilities under its control and direction. The solutions being used were invented by Richard D. Smith of Wei T’o® Associates, Inc., Box 40, Matteson, Ill.

The relationship between U.S. Patent 3,676,182 granted to Dr. Smith, and U.S. Patent 3,939,091 granted to George Kelly, Preservation Research and Testing Office, and assigned to the Library has not been clearly understood until recently. As a result of discussions between the Library and Dr. Smith, the Library has been licensed to use Letters Patent 3,676,182.

Dr. Smith pioneered the development of nonaqueous deacidification solutions during the 1960s at the Graduate Library School of the University of Chicago. His preferred deacidification agent, magnesium methoxide, was utilized by Mr. Kelly through the addition of carbon dioxide to form methoxy magnesium methyl carbonate (MMMC), a chemical by definition, made up of more than 50 percent magnesium methoxide.

The announcement of Mr. Kelly’s patent (see the LC Information Bulletin of March 12, 1976, described the use of MMMC, then called methylmagnesium carbonate, as follows:

Many earlier deacidification techniques were based on aqueous deacidification solutions. Such solutions, although effective in some instances, have drawbacks related principally to the fact that water can be very damaging to some types of paper and to certain inks used for color work or for writing.

Although several nonaqueous or solvent-based methods have also been developed in recent years, each has been subject to some problems, ranging from the toxic nature of the materials involved, to the tendency of some solutions to precipitate in the presence of moisture and leave a deposit on the paper.

Methylmagnesium cabonate eliminates nearly all of the objections encountered with other solvent-based systems. It effectively deacidifies papers too delicate to be treated by aqueous solutions. The solution imparts a level of alkaline reserve high enough to protect the paper against future acid attack, whether these acids are internally generated by decomposing lignins or other compounds, or externally deposited from atmospheric pollution.

Solutions of methylmagnesium carbonate are much more stable than previously available solutions, most of which tend quickly to become inactive. The effectiveness, the longer storage life, the greater convenience, and the significantly lower cost of the new product provide a superior deacidification agent for the use of conservators.

The Preservation Office of the Library of Congress has been using the new process to treat certain books and documents for the past 12 months. The results have been excellent and no adverse effects or difficulties of any kind have been encountered.

With the exception of the Library of Congress, Wei T’o® Associates, Inc., is the exclusive licensee under Dr. Smith’s patent. The objective of Wei T’o® is to encourage persons and institutions who have been manufacturing their own solutions to become customers. It is the Library’s understanding that Wei T’o® has no desire to penalize any person or institution who has acted in good faith thinking that they were licensed under Mr. Kelly’s patent. On the other hand, Wei T’o® has informed the Library that it believes development costs should be evenly spread among all those who benefit. For these reasons, Wei T’o® will merely seek reasonable compensation from those persons and institutions who promptly undertake negotiations. It is the plan of Wei T’o® to improve the quality, variety, and scope of its products and to support research in preservation for the benefit of collectors and institutions like archives, libraries, and museums. Dr. Smith, who is president of Wei T’o®, has indicated that this plan follows his conviction that inventions should produce income and this income should be used to produce further benefits for society.

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