ASTM (The American Society for Testing & Materials) has completed a five-year research program into the aging of printing and writing papers. The research was launched in order to develop accelerated aging test methods that could be used to predict the stability of such papers to the effects of long term natural aging. In order to meet a key goal of the program, it was necessary to show that the chemistry and physics produced by the proposed accelerated aging test methods was essentially the same as occurs in natural aging. That result has been demonstrated in the work now completed.
Five laboratories conducted this work. They pursued three separate test methods. The means chosen to accelerate aging included elevated temperature, elevated light flux, and elevated concentration of common atmospheric pollutant gases. Both the mechanical strength and the optical property stability of fifteen specially produced papers have been investigated in order to develop the test protocols. The fifteen papers of the study included both acid and alkaline furnish and ranged from stone groundwood to cotton fiber. Thirty-three organizations sponsored this $4 million program.
This paper will review the research program and the test methods that will be presented to ASTM for ballot.
See Update, May 2003 for information on obtaining research results on CD.
Because of the terrible damage done by the use of alum-rosin sizing in printing and writing papers, and the acid induced damage caused thereby, a great many books and documents have become so brittle as to no longer be usable. The library, archive and museum communities have therefore insisted that standards for paper requiring permanence that were to be delivered to their safekeeping be based on specific paper composition. The result has been standards that require paper to be alkaline, to contain an alkaline reserve such as calcium carbonate, and to have no more than 1% lignin content. This composition standard arose because of the excellent aging performance of very old papers that had been made to similar specification.
With the continual innovation that occurs in modern papermaking, new additives are frequently developed and included in printing and writing papers. While these additives may perform admirably when the paper is fresh and new, until now tests for its long term stability to the effects of natural aging have been less than fully satisfactory. For that reason, both papermakers and end users of these papers have sought to define scientifically sound methods to test such papers for long term stability to aging effects. If such tests could be developed, a shift could be made to standards that define the performance characteristics of the paper, not only when new, but over an extended period of time. Based on the limits, beyond which the paper would no longer perform to the requirements of a particular end user, an assessment could then be made of the approximate useful life of the paper to that user.
In 1992, discussions took place in ASTM's Committee D6 on Paper and Paper Products. They occurred specifically in the sub-committee that dealt with permanent paper standards. At the time, it was agreed that an effort should be launched to create new accelerated aging test methods. A requirement was that they could be shown to be scientifically sound and that they would properly define the aging stability of any printing and writing paper. To be considered scientifically sound, it was agreed it would be necessary to show that the physics and chemistry of the accelerated aging processes created essentially the same results as would long term natural aging.
After review and fund raising by an ad-hoc committee, ASTM offered a workshop in July 1994. The intention of the workshop was to bring together all parties that had a stake in development of the desired accelerated aging test methods. Its goal was to have workshop participants define the elements of research required to create the desired scientifically sound methods.
The workshop drew over 100 people from 12 countries to Philadelphia where the session was held. In a three-day program, the first day was devoted to presentations by sixteen of the most respected scientists from around the world whose work centered on the aging of paper. Issues covered by the scientists included:
In addition to these presentations, an extensive bibliography of the paper aging literature was offered.
During the remaining two days of the workshop, a facilitated dialog was held to identify research goals and their priority. It was intended that satisfaction of such goals would lead to new, scientifically sound accelerated aging test methods for printing and writing paper. Even though there were people with very different expectations and needs present, it was gratifying that consensus was reached regarding the research efforts required to move forward.
The research requirements included development of methods that would accelerate aging in the paper through use of elevated temperature, by elevated light flux and by elevated concentrations of pollutant gases. Additionally, there was fundamental scientific study required to better understand mechanisms of aging that were at the time, not fully understood.
Requests for proposal were solicited from twenty-five organizations from around the world. At the same time, an intensive fund raising effort was launched. By the end of the program, between outright cash contributions and those that were "in-kind," a total of $4 million USD was raised. Thirty-three organizations contributed to funding the work. That sum of money permitted acceptance of bids from five laboratories whose proposals best met the objectives of the overall program.
The laboratories that won contracts included:
For study of accelerated aging by elevated temperature:
For study of accelerated aging by increased light flux:
For the study of increased concentration of the most common atmospheric pollutant gases as a means to accelerate paper aging:
A concern of the sponsors was that much very good research from the past in the field of paper aging could not be reproduced as there was insufficient documentation of all ingredients and steps taken within the research program. To avoid that pitfall, very great care was taken in the ASTM program to ensure that high quality documentation of all parts of the research was undertaken. That included the manufacture of paper for research study, its storage conditions through time, and the exact procedures used in the laboratories to carry out the research work.
To ensure an ample quantity of paper for research, the sponsors decided it should be specially made for the program on real paper machines. In that way, the directionality that is characteristic to machine-made paper would be included in the ASTM papers. Directionality occurs on production paper machines because the fibers in the paper typically become more aligned in the direction of flow through the machine than across its width. This makes the paper stronger in that direction than in the direction across the sheet. By making the paper for research study on a continuous paper machine (as opposed to making them in a laboratory sheet-making machine), a very large quantity of each paper in the research set could be quickly made.
In total, fifteen papers were produced for research study. Thirteen of those were produced on a pilot paper machine at the Herty Foundation in Savannah, GA. Crane & Co., Inc. in Dalton, MA made an additional two papers on a full production paper machine. The papers produced by Crane & Co., Inc. were of textile grade cotton. All those made at the Herty Foundation were made of wood pulps.
Included in the array of papers tested were papers of both acid and alkaline composition. The range extended from mechanically produced stone groundwood (SGW) to the cotton papers. In between were full chemically produced kraft wood pulps and pulp that was partially chemical and partially mechanical in its production process. This latter pulp is known as BCTMP for BleachedChemiThermoMechanicalPulp. Both softwood (BNSWK) and hardwood (BNHWK) pulps were included. The full set of papers and their composition is shown below in Table 1.
| Table 1 | |||||||
|---|---|---|---|---|---|---|---|
| ASTM Research Into The Effects of Aging on Printing & Writing Papers | |||||||
| Paper Sample Composition | |||||||
| Sample | Pulp Type | Pulp Type | Target | pH Control | AKD or | ||
| Number | Number 1 | Number 2 | pH | Chemical | CaCO3 | Starch | Rosin Size |
| 1 | 100% BNSWK | None | 5 | Alum | None | None | 2#/T Rosin |
| 2 | 100% BNSWK | None | 8.1 | Na2CO3 | 5% PCC | None | None |
| 3 | 100% SW-BCTMP | None | 5 | Alum | None | None | None |
| 4 | 100% SW-BCTMP | None | 8.1 | Na2CO3 | 5% PCC | None | None |
| 5 | 100% COTTON | None | 5 | Alum | None | None | 2#/T Rosin |
| 6 | 100% COTTON | None | 8.1 | Na2CO3 | 5% PCC | None | None |
| 7 | 20% BNSWK | 80% SLUSH-SGW | 5 | Alum | None | None | None |
| 8 | 20% BNSWK | 80% SLUSH-SGW | 7 | SMI Process | 5% PCC | None | None |
| 9 | 20% BNSWK | 80% HW-BCTMP | 8.1 | Na2CO3 | None | None | None |
| 10 | 20% BNSWK | 80% HW-BCTMP | 8.1 | Na2CO3 | 5% PCC | None | None |
| 11 | 50% BNSWK | 50% BNHWK | 8.1 | Na2CO3 | None | None | None |
| 12 | 50% BNSWK | 50% BNHWK | 8.1 | Na2CO3 | 5% PCC | None | None |
| 13 | 50% BNSWK | 50% HW-BCTMP | 8.1 | Na2CO3 | 5% PCC | None | None |
| 14 | 50% BNSWK | 50% HW-BCTMP | 5 | Alum | None | None | 2#/T Rosin |
| 15 | 50% BNSWK | 50% BNHWK | 8.1 | Na2CO3 | 5% PCC | Penford Gum 270 | 4#/T AKD |
The "parent" rolls of paper made on the paper machine were cut to standard office paper cut-size of 8 ½ x 11 inches. Enough paper was produced so that about 30,000 individual pieces were made for each of the fifteen different paper types.
To ensure that each lab had a representative selection of the various parts of production of each paper, all pages of every paper type were thoroughly randomized before being sent to the individual labs. This was done by use of a statistically reliable method for running the paper through a machine collation process.
Prior to submission to any of the research studies, all paper was kept in acid free boxes in cold storage at a temperature just above the freezing mark. This was to keep it both cold and in the dark. In that way, very little aging took place before the experiments were begun.
As noted above, both the Canadian Conservation Institute and the US Library of Congress conducted temperature-aging studies. To some degree, there was overlap in their programs. However, for the most part, they conducted separate, but fully coordinated research activities.
Canadian Conservation Institute: The primary thrust at the CCI was Arrhenius based studies of the two acid containing papers that contained softwood pulp. Thus, CCI did extensive aging of Papers 1 and 3. Paper 1 was the 100% Bleached Northern Softwood Kraft paper and was acidic with pH in the 5 range. Paper 3 was a 100% softwood version of BCTMP and was also acidic. Those papers were chosen because they offered the greatest likelihood for rapid deterioration during the accelerated aging experience.
Exposures were conducted in two formats during the research work. Within a temperature and humidity controlled oven, paper was either hung as free individual sheets or placed as stacks of sheets between glass plates. The stack test was intended to simulate the experience that occurs in natural aging of books in a fairly tightly packed bookshelf.
To ensure that sufficient moisture was retained in the paper at the elevated temperature of the aging procedure, a preliminary set of experiments was conducted. In these tests, evaluation was made of the oven humidity required to preserve paper moisture content at the same level as at ambient condition. The finding was that the relationship between temperature and RH was linear as temperature in the chamber was changed. Higher temperature required higher RH to maintain paper moisture content at constant condition.
Upon development of curves of change in strength properties at different temperatures, it was seen that paper aged in stacks suffered more rapid loss of strength than that aged as free-hung sheets. The rate of strength loss increased with aging temperature. Study of change in degree of polymerization of the cellulose molecules in the paper was also undertaken. As aging progressed over time, DP was seen to decrease and at a faster rate as temperature was increased. Study of DP was especially beneficial because it began to change before significant change in strength properties could be detected. The DP studies also confirmed that stack aging progressed at a faster rate than aging of free-hung sheets at the elevated temperatures.
Arrhenius plots were made from the degradation rates determined at each of the four temperature/RH combinations studied. From those plots, it was seen that activation energies for cellulose depolymerization were similar for both papers. However, those for loss of mechanical strength (fold endurance, tear strength, and zero-span breaking length) were generally modestly higher than those for cellulose depolymerization.
For the temperature range studied (65C to 90C) it was seen that extrapolation to ambient conditions could cause error. A very slight change to the angle of the line drawn through the strength values measured at each temperature could result in unacceptable error when crossing the normal room temperature mark. To improve accuracy, a range of study of lower temperatures would have been required. The time (many months or even years) to carry out such tests was so great as to be beyond the capabilities of the program. The important finding was that the lines plotted through the individual temperature studies were straight, meaning that a consistent aging process occurred. The higher the temperature, the greater the loss of paper strength. That provided confidence that the accelerated test method would provide similar changes in the paper as occur over long periods of natural aging.
Library of Congress: The Library of Congress (LOC) also performed Arrhenius studies. In their case, six papers were evaluated. There were three sets of common fiber furnish evaluated. Each had one acid and one alkaline variant of the same furnish. The fiber furnishes studied included the BNSWK (Bleached Northern SoftWood Kraft), the cotton, and the SGW (Stone GroundWood). Thus, only the acid BNSWK paper was common between LOC and CCI.
At the Library of Congress the same linear relationship between temperature (over the range from 70°C to 90°C) and relative humidity was found to be required to maintain constant paper moisture content in the aging ovens. Upon plotting curves of strength loss over a range of aging times, straight lines emerged, confirming that the process was linear in nature and did not develop a different mechanism of aging either at higher temperature or over a longer period of time.
The LOC not only studied free-hung sheets and stacks of sheets in humid ovens, but also evaluated aging in hermetically sealed glass tubes that were aged in a dry oven. This technique was studied because of its simplicity. Control of RH in humid ovens is a procedure requiring meticulous care. Ovens in which RH can be precisely controlled are much more expensive than dry ovens. In dry ovens, only internal temperature must be precisely controlled.
A unique part of the LOC study was a variety of chromatography evaluations of chemical compounds evolved as the result of the aging experience. In this, HPLC (High Performance Liquid Chromatography), IC (Ion Chromatography), and gel-permeation chromatography studies were conducted. Old papers from the Library of Congress were compared with similar new papers of this program. Additionally, a sample of papers that had been aged naturally for many years that resulted from pilot paper machine runs at the USDA Forest Products Laboratory were also evaluated. It was highly encouraging to find that the chemical compounds formed by aging were essentially the same, whether aged very rapidly in the accelerated process or slowly, over a century or so by natural process. Further confirmation that the elevated temperature aging process did not create new compounds was attained when old papers were subjected to the rapid aging protocol. In that instance, new chemical constituents did not appear. Rather, only more of the same chemicals produced by natural aging were seen to evolve.
Joint CCI/LOC Recommendation: Because of the favorable experience with hermetically sealed glass tubes at the Library of Congress, it was decided that the recommended test method should utilize the glass tube technique. However, since the Canadian Conservation Institute had never utilized the method in their research program, it was decided that they would perform extensive testing of the procedure. In all, they aged eight of the ASTM papers and nine commercial papers from an earlier Canadian study in which they participated. All of these tests showed good correlation with "stack" aged paper results. It was concluded that the sealed glass tube method was that which was most appropriate to recommend for a formal test method.
Light Aging:
As in the temperature-aging studies, the light studies involved the work of two laboratories. KCL in Finland and the USDA Forest Products Laboratory (FPL) in Madison, WI performed light aging research. There was a small amount of overlap. However, most of the work at each site was independent of that at the other.
KCL: Under the able guidance of Dr. Ingegerd Forsskåhl, studies of some of the mechanisms of light aging were probed. Additionally, a small study of aging in the presence of natural daylight was conducted. Finally, all research papers were subjected to elevated light flux in the effort to bring forward a reliable test for determining the optical stability of various papers.
Analytic tools used in performing the light aging experiments included the of UV-VIS reflectance spectral analysis, FTIR-DRIFT and fluorescence studies. Standard measurements of UV-VIS reflectance spectra (from which the amount of yellowing was calculated) were made throughout the program.
Special studies included:
Accelerated irradiation of the experimental papers was conducted both with a xenon arc lamp that utilized appropriate glass filters, and a small fluorescent desk lamp.
The acid-based papers suffered more loss of optical properties than their alkaline counterparts. However, the major dividing line existed between lignin-containing and lignin-free papers. While both suffered some loss of optical properties (reduced brightness and increased yellowness), the lignin-containing papers lost optical properties rapidly and were judged unstable to light exposure. The lignin-free papers lost optical properties only slowly and were judged stable, although changes in fluorescence were observed in the initial phases of light aging.
The findings and conclusions from the special studies noted above primarily contributed to a more comprehensive understanding of mechanisms associated with various conditions of accelerated aging in the presence of increased light flux. Long term natural aging is influenced by a multitude of different environmental conditions where light flux, light spectrum, temperature, humidity, and the presence of pollutants may differ. The work will be reported in the final scientific report of the ASTM research program but are too extensive for review in this paper.
Forest Products Laboratory: Two major elements were included in the work at FPL. In the first, three chambers were constructed in a basement room at the laboratory for long term natural aging of the full set of fifteen ASTM papers. In one chamber, papers were mounted on a wall that faced a window looking north. It was virtually a floor to ceiling window. Natural daylight was the only light these papers saw. In the other chambers, one was fitted with fluorescent light while the other had a halogen light source. In all instances, the chambers were so constructed that no extraneous light from other sources was allowed to penetrate the rooms. The two artificial light sources were configured such that the light flux at the surface of the papers was at a level that would occur at desktop in a well-lighted office space. Bulbs were changed when expected life was only 10% of full design. Thus, a very constant and uniform light was incident on the surface of each of the paper samples. These three natural exposures were launched in 1995 and are still continuing at the writing of this article. The lights have been on continuously around the clock every day of the year. In the daylight chamber, the papers received whatever light was incident each day throughout the day.
The second part of the FPL program involved accelerated aging studies. Two devices were used to promote the aging. One utilized an ultraviolet lamp with a very discrete wavelength of 350 nm to irradiate the papers at the wavelength where greatest optical property damage is known to occur. The other device used a xenon arc lamp (solar simulator) with suitable filters to simulate natural daylight that had passed through window glass. In a standard 4-day exposure, the amount of light flux in the solar simulator was sufficient to provide an amount of irradiation equivalent to approximately 3.3 years of exposure in the north window natural aging chamber. In both instances, care was taken to ensure that the surface temperature of the paper that faced the light source was kept at or very near the normal ambient value in the laboratory.
In the natural aging study, it was found that all papers suffered loss of optical properties over the very long period of the study. This was manifested by darkening (loss of brightness) and yellowing of the paper. For the lignin-containing papers, the loss of optical properties happened quickly. For the lignin-free papers, the loss was much slower, but did occur. In all cases, the property loss eventually reached a steady state condition and there was no further decline. The charts below portray brightness and yellowness changes for a representative array of the papers that were studied.
Paper Brightness Decrease after Extended Exposure To Natural Daylight Through a Window
Yellowness Increase after Extended Exposure To Natural Daylight Through a Window
In accelerated tests, it was found that there was a reasonably good fit between the shapes of the curves for brightness loss for both accelerated and natural aging even though time scales were very different. While it was only possible to approximate the long term natural exposures, by multiplying the results of aging in the solar simulator by 300, it was clear that the accelerated test easily separated general classes of photostability between the papers studied. The lignin-free papers were seen to have high optical stability. Those containing lignin were less stable. Paper that contained a mix of lignin-free and lignin-containing fiber was more stable than that which was composed of a high portion of lignin-containing fiber.
Papers Are Easily Separated Into General Classes of Photostability by Solar Simulator Exposure
It was found that lignin-containing papers could be ranked as to their relative stability between one and another through use of the solar simulator exposure with its full spectrum of light. When lignin-free papers were studied, they were so relatively stable that the solar simulator did not provide good rankings between them. However, use of the 350-nm ultraviolet light did provide good discrimination of the relative stabilities of lignin-free papers.
An unexpected finding from the very long-term natural aging study was that all papers suffered loss of mechanical strength to a degree considerably greater than expected. The best means to measure this loss of property was through fold endurance testing, as fold was confirmed to be the most sensitive of the mechanical strength tests.
Chemical analyses of the products produced by photoexposure showed good correlation between those produced during natural aging and those produced during accelerated aging. HPLC, IR and Raman spectroscopic studies were used to develop this finding.
The Image Permanence Institute was an ideal place to conduct the pollutant aging research. They own two chambers that had previously been constructed for research regarding the effect of pollutant gases on photographic film. The chambers were constructed of materials that were very resistant to the corrosive effects of the gases studied. Airflow within the chambers was very uniform so that every part of every paper sample was uniformly exposed to the pollutant gas. Approximately 5% of the gas was continuously exhausted from the chamber to ensure that products of degradation that might evaporate from the paper did not confound the scientific findings as they were evacuated from the chamber. Temperature and relative humidity in the chamber were controlled to 25ºC and 50% respectively.
The pollutant gas study involved exposing free hung papers to sulfur dioxide, nitrogen dioxide and ozone. These gases were studied individually and in combination. Concentrations of gas of from 10 to 1000 times greater than that found in an indoor office space in a polluted urban environment were utilized to expose the papers. Times of exposure were adjusted to provide a range of exposures of differing length. The lowest level of gas concentration (0.1-ppm of NO2 combined with 0.05-ppm of SO2) was continued for six months, whereas the highest (50-ppm of NO2) was applied for only seven days. Samples were withdrawn from the pollution chamber at regular intervals during exposure to track the change in strength and optical properties that occurred over time.
Seven of the special ASTM papers were included in the study. Two were of acid composition. The others were all alkaline papers. Three of the papers were lignin-free and four contained lignin.
Key findings of the research included:
Change in Fold Strength at 1 ppm NO2
Lignin-containing papers suffered significant increase of yellowness in the presence of NOx, whereas lignin-free papers showed good color stability in the presence of the same gas.
Paper 8 is a Stone GroundWood,
lignin-containing paper
Paper 6 is a pure cotton, lignin-free paper
Based on these findings, it is recommended that nitrogen dioxide be the gas utilized to evaluate the stability of printing and writing paper to long term exposure to common atmospheric pollutant gases. This should be done at high concentration for a short period of time to minimize the time required for conducting the test procedure.
Three new test methods will be submitted to ballot in the ASTM process as the result of this research program. They will all be intended to provide scientifically sound means to reliably predict the stability of printing and writing papers to the effects of long-term natural aging.
Temperature Method: Samples of paper, cut to proper dimensions will be inserted into glass tubes that can be hermetically sealed. They will be placed in a dry oven at 100ºC for 120-hours. Upon withdrawal from the oven, they will be evaluated for M.I.T. fold endurance (or other standard fold test) in the machine direction of the paper, and tear strength in the cross machine direction. Percent retention of the original unaged paper values for these strength parameters will determine the stability to aging of any paper being tested.
Light Method: Samples of paper will be exposed to light from a xenon long-arc lamp controlled to 800 W/m2 as measured in the 290-800 nm wavelength range. Appropriate filters will be utilized to screen out light below 320-nm wavelength. Exposure will be for 48-hours. The equipment will be designed to ensure that the temperature of the paper at its exposed surface is maintained at normal ambient room temperature. Directional reflectance at 457-nm (R), and yellowness (b*) will be the properties to be measured to evaluate the optical stability of the papers to long-term natural aging.
Pollutant Method: Papers will be free-hung in a pollution chamber in which gas circulation is sufficient to uniformly expose all parts of each sheet of paper uniformly. The temperature and relative humidity in the chamber will be maintained at standard conditions of 23ºC and 50% RH. Exposure will be for 120-hours at 50-ppm of nitrogen dioxide. Resistance to fold strength loss (M.I.T. fold retention) and resistance to yellowing (Δb*) will be the properties measured. Preservation of those strength and optical properties from those present in the unexposed paper will be the means to gage the stability of the test paper to exposure to atmospheric pollutant gas.
For papers that are especially important to preserve, it may be important to utilize more than one or even all three of these procedures to determine their total stability to the effects of long-term natural aging. It is possible that a paper may be stable under one procedure, but only moderately stable or even unstable when subjected to another.
At the time of writing of this report, the peer review of the research work was being completed and the first drafts of the proposed test methods were being submitted to ASTM for ballot. It is only after each method has successfully received consensus approval in the ballot process that it will be formally issued as an approved method for general use.
Early in the program, it was recognized that data was not available in which a set of carefully characterized papers had been put aside and carefully measured for the change to their important strength and optical properties over a very long period of time. Therefore, a group of libraries in North America were contacted. Ten such facilities agreed to take and store under controlled conditions a full set of the fifteen papers made for the ASTM program. The four laboratories in North America that conducted research for the study agreed to conduct periodic tests of papers withdrawn from the books at the library. In total, agreement has been reached to conduct ten tests of strength and optical properties over a one hundred-year time frame. The testing is planned to be more frequent at the beginning of the century-long study, as paper is known to lose properties most quickly at the beginning of its life. This will provide future generations with solid natural aging information against which to correlate accelerated aging data.
The ten libraries are located in both urban and small town venues. Some have state-of-art control of their storage spaces and others are much more modest in their facilities. Both dry and humid locations and those that are cold and hot are included in the ten-library geography. A full list of the libraries is shown in Appendix 1.
As mentioned at the beginning of this article, thirty-three organizations provided financial and/or in-kind support to this program. In total, $4 million was raised to support the research. The sponsors ranged from pulp and paper producers and their suppliers to members of the library and archive communities. A full list of these organizations is included in Appendix 2.
Abitibi-Consolidated Inc.
Alberta Economic Development & Tourism
Andritz Sprout-Bauer
Appleton Papers Inc.
Australian Archives
Boise Cascade Corp.
Bowater Pulp & Paper Canada Inc.
Canadian Cooperative Heritage
Ciba Specialty Chemicals Corp.
Crane & Co., Inc.
Degussa Canada Inc.
Domtar, Inc.
Donohue, Inc.
FACTS Institute
Fibreco Pulp Inc.
FICAB
Fletcher Challenge Canada Ltd.
Fraser Paper Inc.
Industry Canada
Millar Western Forest Products Ltd.
National Archives & Records Administration
National Gallery of Art
National Information Standards Organization
National Institute for Conservation of Cultural Property
National Institute for Standards & Technology
National Library of Medicine
Simpson Paper Company
Specialty Minerals Inc.
Stone Container (Canada)
Tembec Inc.
US Library of Congress
USDA Forest Products Laboratory
West Fraser Pulp Sales
ASTM INTERNATIONAL (the American Society for Testing and Materials) conducted an eight year program of research and test method standards making which was completed in 2002. Five internationally distinguished laboratories were involved. The objective of the program was to sufficiently understand the science of the aging of printing and writing paper that reliable test methods could be developed. The test methods were intended to permit all producers and users of printing and writing papers to reliably predict the long term stability of such papers.
Three means to accelerate paper aging were studied. They were elevated temperature, elevated light flux and increased concentration of atmospheric pollutant gas. The laboratories involved included the Preservation and Research Testing Lab at the US Library of Congress in Washington, DC, where temperature accelerated aging was studied. At the Canadian Conservation Institute lab in Ottawa, ON, Canada, companion investigations into temperature aging were undertaken.
Light aging was studied at the USDA Forest Product Laboratory in Madison, WI and at KCL (the Finnish Pulp and Paper Research Institute) in Espoo, Finland
Atmospheric pollutant gas aging was evaluated by the Image Permanence Institute at Rochester Institute of Technology in Rochester, NY.
Extensive reports of the scientific studies were written by each laboratory. To ensure that the findings and conclusions reached were scientifically sound, the reports were given peer review by panels of independent, third party scientists and paper conservators. The happy news was that all five works were found to be scientifically sound. That meant that the recommended test methods were also found to be scientifically sound.
As the result of this work, a compact disk has been prepared that contains all five scientific reports in their entirety. It is now available for purchase from ASTM at the nominal price of $10.00 in North America or $13.00 for foreign orders. These prices include shipping. Those who wish to order a copy of the CD should contact ASTM INTERNATIONAL as follows:
ASTM INTERNATIONALInternet Orders: http://www.astm.org Click "Technical Publications" on first two pages. Enter PAPERAGING in the "Search For" box. Click on "Search" Click on the line labeled "PAPERAGING ASTM's Paper Aging Research Report Program". An abstract will appear about the product. Click on the appropriate "ORDER" button at the top of the document to place an order. Follow the prompts to complete your order.
The CD is ASTM International's first electronic version of a formal ASTM Research Report. It is a technical publication bearing its own reference in published ASTM standard tests as Research Report (RR#) D06-1006.
It is felt that this scientific information will be important for libraries, archives, and museums to have in their collections. Margaret Byrnes of the National Library of Medicine, Susan Lee-Bechtold of the National Archives and Records Administration, and Janet Gertz of Columbia University were on the sponsor review panel as Technical Advisors during the execution of the research work. They were involved to represent the library, archive and museum communities. They endorse the recommendation that such organizations add this document to their collections.
As the outgrowth of the research program, three new test methods were submitted for ballot in the ASTM process. All three successfully passed the consensus ballot process and are now available methods. They can be acquired from ASTM by those interested in testing the long term stability of either new or old papers. For those who desire copies, the designation of each method follows:
Temperature aging method: ASTM D 6819-02
Pollutant aging method: ASTM D 6833-02
Light aging method: ASTM D 6789-02
For questions or additional information on this product, please contact ASTM Standards Manager Thomas O'Toole at 610-832-9739 or by email at totoole@astm.org.
Updated May 2003
![[CoOL]](/icons/sm_cool.gif){kind=icon}