NBSIR 75-739

Development of Specifications for

Archival Record Materials

W. K. Wilson and E. J. Parks

Paper Evaluation Section

Institute for Materials Research

National Bureau of Standards

June 30, 1975

Annual Report

Prepared for National Archives and Records Service

Washington, D. C. 20408

NBSIR 75-739

DEVELOPMENT OF SPECIFICATIONS FOR

ARCHIVAL RECORD MATERIALS

W. K. Wilson and E. J. Parks

Paper Evaluation Section

Institute for Materials Research

National Bureau of Standards

June 30, 1975

Annual Report

Prepared for National Archives and Records Service

Washington, D. C. 20 408

U.S. DEPARTMENT OF COMMERCE. Rogers C.B. Morton. Secretary

NATIONAL BUREAU OF STANDARDS, Richard W. Roberts. Director

Contents

1. Summary 1

2 . Background 2

3. Objectives 3

4. Completed Specifications 4

5. Evaluation of Stability of Copies From 5

Office Copying Machines

6. Accelerated Aging of Book Papers at 100°C 6

Compared with 36 Years Natural Aging

7. Study of Uncoated Book Papers After 10 9

Years of Natural Aging

8. Sorption of Oxygen by Papermaking Pulp

^

9. Accelerated Aging of Handsheets at 90°C 11

and Various Relative Humidities

10. Modification of pH Tests 12

11. Effects of Iron and Magnesium on Alkaline 13

Peroxidation of Carbohydrates

12. Status of Reports and Manuscripts 14

13. Plans for the Period July 1, 1975- 15

October 1, 1976

14. References 16

-1-

1. Summary

Progress during FY-1975 on a long range program on the

Development of Specifications for Archival Record Materials

includes the following:

(1) Report NBSIR 74-501 entitled An Analysis of the

Aging of Paper: Possible Reactions and Their Effects on

Measurable Properties. Although dated April 26, 1974, this

was not included as a completed task in the annual report

for FY-1974.

(2) Report NBSIR 74-498 (R) entitled Evaluation of

Archival Stability of Copies From Representative Office

Copying Machines. Although dated April 30, 1974, this was

not issued until much later and was not included as a completed task in the annual report for FY-1974.

(3) Report NBSIR 74-632, Comparison of Accelerated Aging

of Book Papers in 1937 With 36 Years Natural Aging.

(4) A specification for copies from offical copying

machines for permanent records has been carried through the

task group stage and the subcommittee stage in the ASTM

standards process.

(5) A modification of the standard method, for determination of pH of paper has been developed.

(6) Considerable progress has been made on evaluation of

the effect of relative humidity on the aging of paper. The

effect of moisture at higher relative humidities is so great

that it appears that a low relative humidity would be desirable

for accelerated aging.

(7) Work on oxygen sorption during aging is inconclusive.
-2-

2 . Background

In response to a request by the National Archives and

Records Service, the National Bureau of Standards is developing information on the variables associated with the

stability of archival record materials, especially paper.

Several U. S. Government agencies and the Society of American

Archivists have joined in sponsorship of the project through

National Archives and Records Service.

Many record materials of archival or long-term historical

value in repositories in the Federal Government and throughout the United States are in bad physical condition. If

proper specifications were available for materials that are

designed to be used for permanent records, future problems

concerned with the deterioration of record materials and the

cost of repairing the mistakes of the past would be greatly

diminished.

Much of the earlier work on this project was directed

toward the development of an accelerated aging method. As

this is a long-range effort, in terms of time and scope, and

as archivists and librarians need specifications today for

record materials, interim specifications based on pH requirements have been prepared for selected materials. Work on an

accelerated aging method is continuing, and substantial progress has been made during FY-1975.
-3-

3. Objectives

The objectives of this program are as follows:

(1) The development of information on the stability of

paper and other record materials.

(2) The development of test methods for the evaluation

of the stability of paper and other record materials.

(3) The development of specifications for materials suited

for permanent records.
4. Completed Specifications

The following specifications have been cleared through

the American Society for Testing and Materials (ASTM)

:

D-3208, Standards Specification for Manifold Papers for

Permanent Records. This specification appears in Part 20 of

the 1975 ASTM Book of Standards. It also is available from

ASTM as a single reprint.

D-3290, Standard Specification for Bond and Ledger

Papers for Permanent Records. This specification is available

as a single reprint, and it appears in the 1975 ASTM Book of

Standards

.

D-3301, Standard Specification for File Folders for

Storage of Permanent Records. This specification is

available as a single reprint, and it appears in the 1975

ASTM Book of Standards.

These specifications have been approved by the American

National Standards Institute (ANSI) as ANSI standards.
-5-

5. Evaluation of Stability of Copies From

Office Copying Machines

Technology has provided over the past 20 years a plethora

of machines for making copies of originals by pressing a

button. As some of these copies have not proven to be particularly stable, and as these copies have found their way

into permanent record files in various organizations, specifications for this type of copy are urgently needed. Paper

must be capable of being transported through the copying

machine for which it is intended. The paper may be plain,

coated, or impregnated, and supplies may be purchased from

sources other than the suppliers of the copying machines.

As pH can be used as a sole criterion of probable longevity

only for plain uncoated paper, an accelerated aging method

is required. The only official accelerated aging method for

paper involves oven aging for 72 hours at 105°C. In addition,

stability of the image must be evaluated.

Representative samples were obtained from several manufacturers and tested in order to obtain the data necessary

for preparing specifications for the paper and for stability

of the image. This work has been completed and reported [1].

The specification is based on: (1) minimum pH requirement,

(2) minimum retention of tear and fold after accelerated aging,

and (3) retention of reflectance of image after exposure to

a xenon arc and after abrasion by a standard technique.

The specification has been approved by the ASTM Task

Group on Office Copy Papers for Permanent Records and by

ASTM D06.20, Paper for Permanent Records. It has been balloted

by ASTM D-06, Paper, and a few negative ballots must be

resolved. It should be possible to complete the work within

6 months

.
-6-

6. Accelerated Aging of Book Papers at 100°C

Compared with 36 Years Natural Aging

In 1937 a group of book papers made in the NBS paper

mill was tested before and after accelerated aging for 72

hours at 100 °C. Although there was no plan to test these

papers after natural aging, a collection of some of these

papers had been kept in an office for several years. The

manufacturing history was known and the physical and chemical

properties had been extensively evaluated for that time. Out

of a total 72 papers, 18 were found that could be assembled

to form a reasonably coherent set of samples.

The fiber compositions fall into three categories:

(1) 50-50 soda-sulf ite , (2) purified wood pulp, and (3) old

rag. Chemically, these papers are very different. The sodasulf ite papers contain a high percentage of hemicelluloses , the

purified wood pulps are low in hemicelluloses, and the rag

papers contain no hemicelluloses. The hemicelluloses are

more vulnerable to degradation than cellulose.

The following conclusions may be drawn from the data

obtained on these papers [2]

:

(1) The changes in alpha cellulose that occurred during

accelerated aging for three days at 100°C correlated well

with changes in alpha cellulose that occurred after 36 years

of natural aging. Alpha cellulose, or perhaps some more

convenient alkali solubility method, should be suitable as a

criterion of resistance to accelerated aging.

(2) The same is true for copper number.

(3) Correlations of retention of folding endurance

after natural and accelerated aging were fair only. Although

fold is useful as an evaluation method after accelerated aging,

one should not rely on it completely.

(4) Correlations of internal tear after natural and

accelerated aging were somewhat better than for folding

endurance, but still not great.

(5) Correlations between cold extract pH in 1937 and

changes after natural aging in alpha cellulose, copper

number, fold, tear, and elongation indicate that pH is a

reasonably good criterion of stability.
-7-

(6) Retention of tear after natural aging correlated

well with retention of elongation after natural aging.

(7) Retention of fold after natural aging correlated

fairly well with elongation after natural aging, but not as

well as tear and elongation.

(8) Corrlation between pH and zero span tensile data

for all 18 papers was very poor, but when the data were separated

into statistically homogeneous subsets, the correlations were

better

.

(9) The correlation between pH and breaking load of

wet paper as a percent of breaking lead when dry for the 18

samples was fair only. When the data were separated into

statistically homogeneous subsets, the correlations were

better

.

(10) The correlation between pK and energy at break

for wet paper was fair only.

(11) The correlation between pH and extensional stiffness

for wet paper was very poor. When the data were separated

into statistically homogeneous subsets, the correlations were

fair

.

(12) It appears that pH, and changes in alkali solubility,

reducing power (copper number) and tearing strength after

accelerated aging for 72 hours at 100°C are reasonable indications

of stability. Fold is sensitive, but not as useful.

(13) Although changes after accelerated aging are not

available, it appears from data after natural aging that

zero span tensile and strength when wet as a percent of

strength when dry should be useful criteria.

(14) When data in this report are compared with data

in earlier reports, it appears that dry accelerated aging

more nearly corresponds to natural aging than accelerated

aging at 50 percent relative humidity. The data indicate,

however, that some moisture should be present.

Although this experiment is not at all ideal, it

probably represents the best control over samples and

experimental conditions ever reported on a comparison of

natural aging and accelerated aging.
-8-

Most accelerated aging has been carried out in dry

atmospheres, except that which has been directed towards

evaluation of brightness reversion. Work in this laboratory

has shown that significant differences exist between moist

accelerated aging and dry accelerated aging [3, 4, 5],

Therefore, it is desirable to obtain as much test data as

possible on papers that are still available that were

subjected to accelerated aging several years ago.
-9-

7. Study of Uncoated Book Papers After

10 Years of Natural Aging

The data from this group of papers are disappointing,

and it is unlikely that a useful report can be written. The

papers are too heterogeneous and not enough is known about

them to be able to connect cause and effect. If time

permits, another attempt will be made, but the situation is

not encouraging.
-10-

8. Sorption of Oxygen by Papermaking Pulp

It has been shown in earlier reports [3, 4, 5] that

the degradation of paper is influenced by both oxygen and

moisture. Oxygen sorption is an easy experiment to

run in the laboratory, as the set-up requires little attention once it is placed in operation. Several sorption experiments were initiated in which tubes containing papermaking

pulp were filled with humidified oxygen and placed in constant temperature baths at temperatures ranging from 50° to

90° . The data obtained so far are inconclusive. The experimental conditions appear to determine whether oxygen is sorbed

or gases are evolved. At 90°C the pulp discolors badly and

a brownish liquid collects in the bottom of the aging vessel.

The work is continuing.
-11-

9. Accelerated Aging at 90°C and Various Relative Humidities

Work on the accelerated aging of laboratory handsheets

at N.B.S. has employed a temperature of 90°C with Air or

nitrogen at 50% or 0% relative humidity. Comparisons of data

obtained after natural aging with those data obtained after

accelerated aging under these conditions suggested that

neither of these extremes in relative humidity approximated,

in key processes, the changes to be expected in natural aging.

A relative humidity of 50% appears to promote hydrolytic

decomposition too rapidly, whereas cry aging promotes crosslinking reactions to an extent that is out of proportion with

the occurrance of crosslinking in natural aging. So it was

felt that some intermediate relative humidity might be more

desirable if accelerated aging at a high temperature were to

be feasible.

Paper prepared from deashed pulp has now been aged for

periods up to 24 days at 90°C and 0%, 5%, 20% and 50% relative

humidity to assess the aging effects of increasing amounts of

moisture

.

Tests have been conducted to determine changes in folding endurance, tearing resistance, brightness, moisture regain,

pH, alpha cellulose, and copper number. Further tests will

include determination of zero span tensile strength, dry and

wet tensile properties, and probably some thermoanalytical

properties, but these tests must await the availability of

instruments

.

The work completed so far shows that rates of change in

the physical and chemical properties are highly dependent

on relative humidities.

The data are incomplete, but it already is clear that

extended aging at 50 percent relative humidity is not

desirable. Although 20 percent relative humidity as an

aging condition might be acceptable, it appears that a lower

figure would be better.
-12-

10. Modification of pH Tests

In the course of many pH determinations in this laboratory,

it was observed that pH readings decreased slightly (0.1 to

0.2 pH unit) if paper in suspension came into light contact

with the reference electrode, and further decrease could be

obtained if close contact was deliberately effected. Even if

one is aware of this effect, it is sometimes difficult to avoid.

Inspection of data obtained in the interlaboratory testing program

conducted by NBS, suggested that the effect may commonly

interfere with pH tests and should be avoided by making tests

on decanted solvents. A manuscript on this topic is being

prepared

.
-13-

11. Effects of Iron and Magnesium

on Alkaline peroxidation of carbohydrates

Since January 1, 1975, E. J. Parks has been conducting

research at American University, under the direction of

Dr. Horace S. Isbell, on the mechanism of the alkaline

peroxidation of carbohydrates, its acceleration by ferrous and

ferric ions in solution, and its retardation by magnesium

ions. These studies will in part comprise the topic of

Parks' PhD dissertation. Magnesium ions are useful for reducing cellulose depolymerization during commercial bleaching

processes with hydrogen peroxides, possibly because they form

unreactive complexes with ions that promote the decomposition

of hydrogen peroxide into reactive free radicals. The

relation to paper permanence is quite speculative. However,

as indicated in NBSTR 74-499, the formation of hydrogen

peroxide in small amounts may also occur during the oxidative

aging of paper. Methods for preventino the decomposition of

H 2 0 2 in catalytic amounts may consequently be of interest,

from the permanence standpoint.
-14-

12. Status of Reports and Manuscripts

(1) NBSIR 74-499 An Analysis of the Aging of Paper:

Possible Reactions and Their Effects on Measurable Properties.

Dated April 20, 1974, but report was not issued until much later.

(2) NBSIR 74-498 Evaluation of Archival Stability of

Copies From Representative Office Copying Machines. This

includes a draft specification. Dated April 30, 1974, but

report was not issued until much Later.

(3) NBSIR 74-6 32 Accelerated Aging of Book Papers for 72

Hours at 100 °C Compared with 36 Years Natural Aging.

Issued December 18, 1974.

(4) Accelerated Aging of Commercial Book Papers at 90°C

and 50 Percent Relative Humidity Compared with 10 Years

Natural Aging. The testing of these papers is completed, but

it does not appear that the data are of sufficient value to

warrant a report.

(5) A Review of Accelerated Aging of Laboratory Handsheets.

This was to be a review of three earlier NBS reports, 10 627,

10 628, and 106 87. It was hoped that a review of the data

in these reports coupled with data obtained on the naturally

aged papers would enable some conclusions to be drawn concerning

an accelerated aging test. Much of the data from these three

reports was included in NBSIR 74-632, so the need for a separate

report is not now so pressing. If time permits, however, it

will be written.

(6) Sorption of Oxygen by Papermaking Pulps. Data for

this report are incomplete.

(7) Accelerated Aging of Handsheets at 90°C and Various

Relative Humidities. This is partly written, but more data

are needed.
-15-

13. Plans for the Period July 1, 1975-

October 1, 1976

The following tasks will receive top priority:

(1) Accelerated aging of handsheets at several temperatures

and at low relative humidities.

(2) Sorption of oxygen by papermaking pulp in humidified

oxygen atmospheres

.

(3) Finalize the specification on Copies from Office

Copying Machines for Permanent Records

.

The following tasks will be pursued if time permits:

(1) Study of old papers in order to determine what

actually happens during the aging of paper.

(2) Finalize a revision of the method for determination of the pH of paper.

(3) Complete the report on a review of earlier reports

on aging of handsheets, NBS Reports number 10627, 10628

and 10687.

(4) Complete the report on the study of uncoated book

papers after 10 years of natural aging. This has a low

priority

.
-16-

14. References

Parks, E. J. and Wilson, W. K. , Evaluation of Archival

Stability of Copies from Representative Office

Copying Machines, NBSIR 74-498 (R).

Wilson, W. K. and Parks, E. J. Comparison of Accelerated

Aging of Book Papers in 19 37 with 36 Years Natural

Aging, NBSIR 74-632.

Parks, E. J. and Hebert, R. L. , Accelerated Aging of

Laboratory Handsheets: Changes in Acidity, Fiber

Strength, and Wet Strength, NBS Report No. 10627.

Parks, E. J. and Hebert, R. L. , Accelerated Aging of

Laboratory Handsheets: Retention of Folding Endurance,

Internal Tear, Bursting Strength, and Tensile Strength,

NBS Report No. 10628.

Parks, E. J. and Hebert, R. L. , Accelerated Aging of

Laboratory Handsheets: Reflectance, Moisture Regain,

Sonic Modulus, and Differential Thermal Analysis,

NBS Report No. 106 87.
MA (MK V. 7-79) U4. OtPT. or COMM.

BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR RKPORT NO.

NBSIR 75-739

2. Gov't Accession

No.

3. Recipient's Accession No.

*. TITLE AND SUBTITLE

Development of Specifications for Archival Record

Materials

5. Publication Date June 20, 1975

6. Performing Organization Code

311.05

7. AUTHOR(S)

W. K. Wilson and B. J. Parks

1. Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OP COMMERCE

WASHINGTON, D.C. 20234

10. Project/Task/Work Unit No. 3000442

11. Contract /Grant No. annual

12. Sponsoring Organisation Name and Complete Address (Stroot, City, Stmt*, ZIP)

National Archives and Records Service

Washington, D. C. 20408

11. Tjrpe of Report & Period

Cohered

14. Sponsoring Agency Code

none

15. SUPPLEMENTARY NOTES

14. ABSTRACT (A Mfrword or /•«• detail ——| olmomt itftltlcant Information. II docummt includea a aifrtlicmt

bibliography or lititata aurray, smoHom it Hon.')' A specification for copies from office copying machines for permanent

records has been prepared and is progressing through a standards

organization. A project on the effects of 36 years of natural aging

on a group of book papers of known composition was completed and

reported. Work on the accelerated aging of handsheets at various

relative humidities is incomplete, but data already obtained show

that a low relative humidity is desirable in an accelerated aging

procedure. Data on the sorption of oxygen by papermaking pulp at

elevated temperatures are inconclusive.

17. KEY WORDS (aix to twalra entries; alphabetical order; capitalize only *• lint letter ol me tint key »orrf unleae a proper

name,- aeparatad by ••mfeo/one;

Accelerated aging; Natural aging; Permanence; Record materials;

Record papers; Stability.

18. AVAILABILITY []g Unlimited

F °f Official Distribution. Do Not Release to NTIS

Order From Sap. of Doc., U.S. Government Printing Office Washington, D.C. 20402, SD Cst, No. CM

QDPfder From National Technical Information Service (NTIS)

Springfield, Virginia 22151

19. SECURITY CLASS

(THIS REPORT)

UNO. ASSIFIED

20. SECURITY CLASS

(THIS PAGE)

UNCLASSIFIED

21. NO. OF PAGES

16

22. Price

$3-25

UlCOMM.DC 2»042-»7«

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