The Alkaline Paper Advocate

Volume 3, Number 1
Mar 1990

Remarks on House Resolution 226 To Establish a National Policy on Permanent Paper

by William K. Wilson
Guest Worker, Preservation Policy and Services Division,
National Archives and Records Administration

1. Introduction

House joint Resolution 226, introduced by Pat William (D-Montana), is the House version of the Pell Resolution (S.J. Res. 57), which was passed unanimously in July 1989. A subcommittee of the House Operations Committee held a short hearing on the House resolution February 21, and several witnesses, including the Archivist of the United States and the Librarian of Congress, supported the resolution's urgent recommendation that federal agencies and American publishers use permanent paper.

The Committee is to be highly complimented on taking the initiative in this area. The need has been extensively documented many times, so there is no reason to repeat this documentation here.

The implementation of the resolutions may be somewhat complicated, since it will involve a mixture of technology, implementation of standards, co cation among interested and uninterested parties, financial resources, and the possibility of unduly impacting the marketplace if too much is requested too soon.

The technology for making very stable papers has been in place since 1901 when Sutermeister at S. D. Warren first made paper with a calcium carbonate filler. This is now referred to as "alkaline-filled paper," but the term is a little unfortunate.

Implementation of standards is a matter of developing appropriate standards that can be used to facilitate communication between buyer and seller, and creating an atmosphere in which they can be used. Simple, but not so simple.

With respect to communication, paper is made by the papermaker, printed by the printer, sold as a publication by the publisher or as an office paper by a converter, and acquired for use by the archivist, librarian and general public. So the archivist and librarian seldom are in a decision-making capacity with respect to the paper that appears in their records. The problems in communication are obvious.

With respect to financial resources, problem have arisen in the past because acid-free papers tended to be more expensive for the consumer than acid papers. As many mills are converting to alkaline system , this objection is now heard less frequently and is likely to disappear in a few years.

Impacting the marketplace could become a real problem if the demand for acid-free papers increases too quickly. This fact of economics is as old as the hills, but should be kept in mind; otherwise, too much progress too soon could do more harm than good.

2. Definitions

As quantitative communication is impossible unless there is agreement on language, some term that might be misunderstood are defined here. It should be understood that agreement on the definitions is not necessarily universal.

Permanence - This basically is a function of the chemical stability of the paper and its ability to maintain initial properties over a long period of time. Permanence must be defined with respect to the end use, as one record might be expected to last 50 years and another to last several hundred years. Librarians and archivists usually expect their holdings to endure for several hundred years.

Durability - This is the capacity of a paper to resist the effects of wear and tear in a performance situation. For example, paper currency should be durable, but maximum permanence is not necessary.

Acid-free paper - A paper that contains no and . This could be 1) a paper that has been sized with rosin and alum (aluminum sulfate) in which the quantities of alum and rosin produce a neutral sheet, 2) a paper in which the alum has been neutralized with sodium aluminate, 3) a paper that has been sized with a neutral or alkaline synthetic sizing agent, or 4) a paper that has been sized with a neutral or alkaline synthetic sizing material and which contains a filler of calcium carbonate. Thus an acid-free paper needs more definition than it usually is accorded.

Alkaline-filled paper - A paper containing a filler of calcium carbonate. This term is unfortunate, for the implication is that the paper is filled with alkali. As calcium carbonate gives a slightly alkaline reaction, the term "alkaline-filled" developed logically into an illogical situation. Although other insoluble carbonates, such as magnesium carbonate, could be used to provide an alkaline reaction, this is not now industry practice.

Buffered paper - This also is a paper containing calcium carbonate. A measurement of the intensity of the alkalinity of such a paper would indicate a very mild alkalinity, for the intensity of the alkalinity does not depend an the amount of calcium carbonate present. Thus, the calcium carbonate could be gradually used up through exposure to atmospheric pollutants without changing the Measurement of the intensity of the alkalinity--which is usually expressed in pH units.

pH - The pH scale is a method of expressing the strength of a solution of an acid or an alkali m a scale from approximately one to 14. A pH of 7 is neutral. Numbers below 7 are in the and range, and numbers above 7 are in the alkaline range. A calcium carbonate filler by itself imparts a pH usually in the range of 7.5-8.0. A paper with a pH value of 5.5 is mildly acid, but not in the dangerous range. A pH of 4.0 would be unacceptably acid for a permanent paper.

Accelerated aging - This is the measure of a paper to a harsh environment in order to estimate its stability in relation to other papers. examples of a harsh environment are exposure to a temperature of 105°C in a dry oven, exposure in an oven maintained at 90°C, 50% relative humidity, or exposure to the light of a carbon arc or a xenon arc. Retention of physical and chemical properties after aging is a measure of the stability of the paper. Obviously, it is necessary to build up a substantial fund of data before an accelerated aging procedure can be of value.

3. Background

Although Sutermeister presumably made the first paper containing a calcium carbonate filler in 1901, the importance of this only gradually became apparent. Costa Hall, a scientist from Sweden working at the National Bureau of Standards, emphasized (1926) that the use of excess alum in papermaking would cause instability. He used accelerated aging at 100°C to show in a semi-quantitative way that alum was bad for paper. The conservation literature, even in the 1800s, is full of descriptions of the bad effects of alum.

The National Bureau of Standards in the 1930s showed that stable papers could be made by paying close attention to the alum-rosin stoichiometry, or by using a calcium carbonate filler. Unfortunately, standards never were developed from this research.

In the late 1950s W. J. Barrow developed a specification for a permanent-durable book paper, but this was never formalized through a standards organization. Without the administrative framework of a standards organization to automatically review the specification every five years, it died a natural death.

About 1970 the National Archives and Records Service sponsored research at the National Bureau of Standards that led to the development of four specifications for permanent record papers. These specifications also became national standards by processing through the American Society for Testing and Materials (ASTM).

Early in the 1980s work was started on the development of a standard for permanent book paper by the National Information Standards Organization (NISO) and this resulted in a standard for uncoated book paper in 1985.

The Congressional Joint Committee on Printing has provided specifications for printing papers for over 70 years, and presently provides seven specifications for papers intended for permanence.

In the early part of this century the emphasis was more on fiber content than on other components of paper, such as alum, for the development of stability. Thus, rag papers were supposed to be the ultimate in stability. A treatise of several volumes that was printed in 1906 on the best rag paper that was available was brittle by 1940. The paper had a high acidity, and bad been made with an excess of alum.

We now know that papers made from either wood pulp or rag may cover the complete spectrum of stability. The best papers are made, regardless of the source of the fiber, from fibers that have been changed chemically as little as possible in the cooking and bleaching processes. Assuming a good fiber source, the most stable papers, over the long haul, which is our principal interest, are made with a synthetic sizing material and contain a calcium carbonate filler. The next best would be papers made with a synthetic size, but no calcium carbonate. Such papers would be vulnerable to acidic gases sorbed from the atmosphere.

Very stable papers may be made using rosin-alum sizing, as shown by research at the National Bureau of Standards in the 1930s. However, this approach is not likely to be efficient in a commercial mill environment.

4. Status of Standards for Papers for Permanent Records

4.1 Available Standards

American Society for Testing and Materials (ASTM) D-3208 Manifold papers

D-3290 Bond and ledger papers
D-3301 File folders
D-3458 Copies from office copying machines

American National Standards Institute (ANSI)

ANSI Z39.48 Permanence of paper for printed library materials (This standard was developed by NISO.)
USAS Z85.1 Permanent and durable catalog cards (The USA Standards Institute was the predecessor of ANSI.)

Congressional Joint Committee on Printing

D50 - Fine writing paper
B60 - Chart, lithographic-finish
G80 - 10%. Bond (% refers to % rag fiber in paper) H10 - 100% Parchment deed
J30 - 100%. Ledger
K30 - 100%. Cream white index
A270 - Uncoated permanent printing paper

4.2 Standards in the Development or Revision Stage

American Society for Testing and Materials

The four specifications mentioned above will be revised in 1990.
A new guide for permanent book paper is in the final stages of development. It should be finalized by the end of 1990.

American National Standards Institute

NISO is revising the standard for uncoated book paper, and adding requirements for coated paper.

Congressional Joint Committee on Printing

No known activity

International Standards Organization (ISO)

A joint working group has been created between TC 6/ Pulp, Paper and Board, and TC 46/Information Sciences, to develop a standard for permanent paper. Sweden is the convenor. The U.S. is supplying representation from technical advisory groups (TAG) in both TC 6 and TC 46.

5. Use of Standards in the Procurement Process

5.1 General Approach

It is almost impossible to specify properties of a paper that can be measured in the laboratory that will guarantee that it will be suitable for the intended use. One must rely on experience, and on the cooperation of the supplier. Therefore, great care must be taken in the development of standards that an unnecessary property is not specified. And an all-inclusive statement usually is added: "The paper shall be suitable for the intended purpose." This, of course, is an admission that one does not know how to write a quantitative standard.

5.2 Formulation of Standards Useful for the Procurement of Permanent Paper

A standard for the procurement of permanent paper needs three parameters: 1) A measure of the strength of the paper related to durability, 2) a measure of composition variables related to stability, and 3) retention of properties after a period of accelerated aging. These situations demand that a fund of data be built up from the testing of a large number of papers that are available in the marketplace. Only then is it possible to write meaningful figures into a standard.

It is also desirable to have some correlations of natural aging with accelerated aging. Although a few such experiments have been carried out, only very general conclusions can be drawn. Another approach is to test old papers in an attempt to determine which properties of paper contribute to degradation.

Several strength properties of paper may be evaluated in the laboratory. Some such properties are tensile at break, elongation at break, tensile energy absorption, tearing strength, bursting strength, and folding endurance.

Properties useful in determining compositional variables important to stability are pH, content of calcium carbonate, fiber analysis to detect groundwood and unbleached pulp, and aluminum content to detect the use of alum.

Not all physical properties are useful in the measurement of change after accelerated aging. The most useful ones are elongation, tensile energy absorption and tearing strength.

5.3 Defects in Present Standards, and how Revisions will Help

ASTM standards. These standards were all right for the time they were written, but no longer. Three levels of permanence, based on pH level, are specified. Although an alkaline filler is specified for the maximum-permanence level, a coating containing calcium carbonate could be mistaken for filler in the analysis. The paper itself could be a very acid paper, and very unstable. The pH levels of the other two permanence categories, 6.5-8.5 and a minimum of 5.5, could be achieved in ways that would not be indicative of permanence.

These standards will be revised shortly to include an accelerated aging procedure, and various levels of retention of properties for the three permanence categories.

The new guide for permanent book paper will be written along the same lines. The retention of properties after accelerated aging is the key to a good standard, and enough information on accelerated aging is available to make this possible.

ANSI-NISO Standard. This standard for book paper allowed a small amount of coating on an uncoated paper, and it was possible to incorporate enough calcium carbonate in a coating to provide an acid paper that still passed the pH test and the carbonate content test.

This will be taken care of in the current revision.

Congressional Joint Committee on Printing. With the exception of A270 Uncoated Permanent Printing Paper, the JCP specifications allow fairly acid papers for permanent records. A270 is patterned after the NISO standard, and specifies an alkaline filler.

International Standards Organization. This standard is not far enough along to evaluate, but it appears that an accelerated aging method will be specified.

6. Recycled Paper

There is a strong movement to require the use of recycled paper in most paper that is purchased by the U. S. Government. Statistically, fibers are not as robust physically and chemically when recovered and used the second time. And as the use of waste paper becomes more common, some of the fibers will be used for the third, fourth and fifth time. This certainly will have an adverse effect on strength properties. This has been documented in the technical literature.

If a calcium carbonate filler is required, the effect of recycled paper on permanence should not be catastrophic. However, there is a limit beyond which recycled fiber should not be used in papers that must have a high degree of permanence, and this limit has not been defined. This requires laboratory work with some well-planned experiments.

In addition, recycling can bring unexpected impurities that may have an adverse effect on permanence. One example is aluminum that is bound to the cellulose acid groups.

7. Summary

Technical implementation of the Congressional resolutions an acid-free paper is feasible now, but the proper standards are not in place to do a good job.

ASTM, NISO and ISO are moving rapidly to develop and revise standards that will allow adequate technical implementation of the resolutions.

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