Chapter VIII

A Study of Paper Permanence

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∣📄 p.95 This chapter has been subjected to criticism by the Bureau of Standards, and the Permanence and Durability Committee of the Technical Association of the Pulp and Paper Industry. The latter body contested certain conclusions of the paper as originally submitted and has expressed a wish that the chapter be published as amended by then, if it is to be published with their approval. Comments and controversial material, therefore, which had been written in the original draft of this chapter and revised out of it, have sometimes been inserted here as footnotes; the substance of the chapter as it stands without the footnotes has been issued separately as a report of the Technical Association of the Pulp and Paper Industry.

∥ The outstanding qualities required of a book paper are four: printing surface, opacity, strength, and permanence and durability. Other qualities of a greater or lesser importance are color, feel, formation, aesthetic value, etc., depending on the purpose for which the paper is to be used. The printability, opacity, and strength qualities of book paper can be determined by suitable testing instruments and expressed in numerical terms. The fourth outstanding quality, namely, permanence and durability, is not as easily expressed. Permanence of a paper has been defined as the degree of resistance towards the degrading chemical action of the impurities in the paper or of materials in the surrounding air. Durability is the degree to which the paper retains its original qualities under usage. In a 1933 report from the Bureau of Standards,¹ it was brought out that important factors in the permanence and durability of book papers are the chemical purity of the fibers in the sheet, and the conditions under which the books are kept. Paper from books stored in urban institutions is uniformly more deteriorated than that from identical volumes kept in rural libraries, according to the Bureau of Standards investigation. The much thumbed-over books in the children’s department of the public library ∥ show the results of wear in use, but there is little doubt that the lasting quality of paper is not only dependent upon its environment but is partly related to the paper itself. This permanence quality, however, is not immediately apparent to the observer. The only absolute test of permanence and durability would require that one should wait to see what happens to the paper in the course of several centuries or until there is positive evidence of deterioration.

In the days when paper was an innovation in Europe, competing with parchment, it was regarded as dangerously impermanent, and there was legislation to prohibit its use in legal documents. Of the books printed in the earlier centuries, enough have endured the effect of time to establish beyond question the permanence possibilities in papers made of the materials then in use. During the period 1875–1910, unpurified or crude fibers, such as ground wood, were frequently used in book papers. The Bureau of Standards, in its report, to which reference has already been made, found that book papers containing appreciable quantities of crude fibers were invariably in poorer condition than those containing rag and chemical wood fibers. The period 1875–1910, therefore, is defined as one in which the paper in books published ∣📄 p.96 in this period may be quite impermanent. This served to emphasize the importance of the chemical purity of the fibers themselves as a factor in the permanence of paper. At the beginning of the present century, paper technicians were calling attention to the danger of printing on paper containing crude fibers, such as ground wood pulp. The conclusion was drawn at that time that papers had a life expectancy proportionate to the amount of rag stock used in their manufacture.²

The distributing trade had little knowledge concerning the problem of paper permanence and durability. The market designations of paper ordinarily in use include size, weight, color, surface finish, and a description of the raw materials from which the paper is made. The raw material may be described with varying degrees of precision. The simplest distinction is that which runs between “rag” and “wood pulp” papers, and those which contain different proportions of both. The rags, however, are not of equal quality. The hardest and most durable fibers are the new unbleached cotton trimmings which are bleached in the paper mill. Then come the scraps left from the manufacture of overalls, “new blues;” then the white rags from wornout clothing from the housewife’s rag bag;³ and, finally, soiled rags of different colors from different sources.⁴ The higher classes of rags require less chemical treatment for paper stock and, therefore, yield a more permanent paper when carefully manufactured. The lower classes of rags usually undergo a more drastic chemical treatment before being converted to paper and do not yield as strong or as permanent a paper, although for many purposes it may possess other more desirable properties.⁵ The wood used in paper making is also subject to various classifications: there is the distinction between the soft (coniferous) woods and the hard (deciduous) woods. Then there are different processes by which the wood is converted into pulp to receive consideration. First, there is the important distinction between “mechanical wood pulp” ∥ (groundwood) and “chemical wood pulp.” Newsprint paper, for instance, is chiefly mechanical wood pulp; most book paper is made of chemical wood pulp. By different kinds of chemical treatment the impurities in the wood are removed and a fiber of relatively high purity, compared to a mechanical wood pulp fiber, is obtained. “Soda pulp” is made by digesting wood chips in an alkaline solution, such as sodium hydroxide, and is composed of fibers from hard woods. “Sulphite pulp,” on the other hand, is made chiefly from soft woods by digesting the wood chips in a solution of sulfurous acid and calcium bisulphite. The fibers generally possess different properties compared to those made by the soda process owing to their difference of origin. Recently certain additional processes giving further purification to chemical wood pulps have appeared.

Within the past decade or so; some paper users have become dissatisfied with the more or less crude paper specifications and have begun to introduce laboratory procedures in standardizing their paper purchases. The distributing trade has not followed this line of development, however; its interests have been heavily vested in the existing trade practices. Recently some of the larger users of papers, who could establish direct contact with the manufacturers, began to demand and to receive “specification papers.” It is reported that about 1% of the finer paper trade in 1928 was on a laboratory specification basis, and that by 1933 this had risen to 10%.

The specifications which were most successfully established were those relating to the physical strength qualities of ‘ the paper. Standard physical tests were tearing resistance, bursting strength, tensile strength, and folding endurance. For nearly ten years government specifications for permanent all-rag content papers have carried requirements as to the grade of new rag permitted. In addition, limits as to rosin size and acidity have also been included. Specifications relating to ∣📄 p.97 probable longevity of a paper were not so easily set up but progress is being made in that direction.

The librarians seem to have been the ones who showed the first and greatest desire for permanence in book papers, but they were in a bad strategic position for making their desires effective. They were many times removed from the paper manufacturers; they had little influence on the publishers and none on the paper distributors. The British Library Association set up a committee which drew up some permanence specifications for paper. In general, however, the paper trade continued to sell its goods as “100% rag,” “50% rag,” or “Sulphite” and induced the buyer to believe that the more he paid, the greater was the probable longevity of the paper.

When the laboratory men began to work on paper specifications, not only was the source of the fiber studied but its chemical and physical qualities were examined. The most important material comprising the fibers used in papermaking is the organic substance known as cellulose, the cell wall of the plant, and its chemical properties are essentially the same whether it is found in the cottonseed hair, cornstalks, or trees, whether it goes to the paper mill as a discarded shirt or a spruce log. In all papers cellulose is the basic ingredient, although there is a big difference in the structure of different fibers and this is an important characteristic in papermaking. Furthermore, associated with cellulose in the crude or unpurified fiber, there are often undesirable substances, called impurities, which are removed by chemical treatment as already indicated. These impurities vary in nature and in amount, depending on the source of the fiber. Ordinary pulp wood is composed of over 50% cellulosic material and “impurities” to the extent of about 30%. When newsprint paper is made by grinding logs into mechanical wood pulp, all the “impurities” or undesirable substances go into the paper. Raw cotton, on the other hand, represents a fiber containing about 90% cellulose and a minimum of “impurities.”

∥ Tests which are often used to determine the purity and quality of the fibers composing a paper are: acidity, sizing, alpha cellulose, and copper number. In general, there is agreement among paper technologists that the acidity and the rosin sizing should be kept low for a permanent paper. The alpha cellulose content of a paper refers to that portion of the cellulose which is not soluble in a solution of sodium hydroxide under certain defined conditions.⁶ These are entirely empirical conditions however. The alkali-resistant or alpha cellulose content of the cellulose portion of a paper is presumably proportionate to the fiber purity, a high percentage alpha cellulose value being desirable for a permanent paper. The copper number is also indicative of fiber purity, the higher the number the greater the degree of damage to the fibers. Other tests which have been used in specifying book papers for permanent records are: ash, folding endurance, bursting strength, opacity, weight, and thickness. No single test can be considered at the present time as an adequate criterion of paper permanency. Even the lists of tests, mentioned above, yield a not too satisfactory picture of the probable life expectancy of a paper as far as purity of the sheet is concerned. Other tests which may become more reliable indices of paper permanence are now in the process of development.

Paper manufactured from the highest grade of cotton rags receives the minimum of treatment. The raw material itself is of a very high degree of purity and, carefully processed, yields from known experience a paper of very great permanence and durability. Such papers possess an alpha cellulose content well over 90% and « copper number considerably less than 1.0. Lower grade rags and chemical wood pulps require more severe treatment in their isolation or purification before being converted to paper. Ordinary processes of making chemical wood pulp do not yield a product with 90% alpha cellulose content. Purification processes are now available, however, whereby the alpha cellulose content ∣📄 p.98 of such pulps, referred to as “alpha pulps,” approaches that of the better grades of cotton rags.⁷

When purified, chemical wood pulps have proven very satisfactory for certain papers and as a substitute for certain grades of rags. With our increasing knowledge of paper, its raw materials and manufacture, the future may provide a more permanent paper made from a greater variety of materials.

Proposed Classification and Specifications for Permanent Book Papers

(1) Classification of Book Papers Relative to Their Permanence Qualities⁸

A system of classification of printing and writing papers relative to their permanence qualities has been suggested by the United States Bureau of Standards.⁹ Mr. B. W. Scribner, of the Bureau of Standards, proposed that the ingredients to be specified be a percentage of alpha cellulose, and he suggested, as an additional innovation, an accelerated aging test om “Stability” specification. Underlying this test is the assumption that paper deterioration is a chemical action which can be accelerated by the influence of heat. Paper samples of known alpha cellulose content, chemical purity, and physical strength are subjected to oven heat for seventy-two hours at 100° C., and then tested for loss of chemical and physical qualities. The loss is expressed as a percentage. This classification is based upon the purity and strength of the finished paper. The values given are derived from the results of the extensive investigations of the Bureau during the past four years into the permanence of paper. In these investigations, tests similar to the ones described here have been made on a large number and variety of papers, and it is believed that papers ful∥ filling the requirements of the various groups will have the relative degrees permanence indicated.¹⁰

In this system of classification, all papers are divided into four classes. The first class contains those papers which may be expected to have maximum longevity. A book paper fulfilling the requirements of this class would be particularly suitable for bound volumes of records having permanent value. The second class contains papers of high purity. Papers used for semi-permanent records and in fine editions of rare and costly books should fulfill the requirements of this class. The third class is composed of papers which, while not having as high a degree of purity as those in the first two classes, have a fair degree of purity. Such papers could be used where moderate longevity is desired, such as in reference periodicals. Papers in the fourth class are those suitable for current use only.¹¹ Table XXXIV, on the following pages, illustrates in detail how such a system of classification might be applied to book papers.

(2) Specifications of the Joint Committee on Printing U. S. Government.¹²

The paper must be made with every precaution to insure the maximum serviceability and permanency. Care must be taken to use the minimum quantities of bleach, rosin, size, and alum. The finished paper must not show the presence of any injurious residual chemicals which will interfere in any way with the permanency of color or the serviceability and durability of the paper. ∣📄 p.99

∥

The Paper Trade and the Proposed Specifications

The interest of the paper trade in specifications is recent and welcome. Technical knowledge is far ahead of the market conditions. Some of the conclusions of paper technologists are in satisfactory agreement and can be used safely as a guide by publishers in search of permanent paper. However, on entering the market to buy paper, the publisher discovers that the distributing trade is not accustomed to the use of even the minimum specifications upon which there is agreement.

The Rag Paper Division of the Writing Paper Manufacturers! Association has suggested tentatively some specifications, which are set forth in a comparative table at the end of this chapter; but for a final judgment on permanence specifications, it awaits the conclusion of the experimental work in progress.

A test made at the Bureau of Standards confirms the fact that a purchaser who merely specifies a percentage of rag content in a book paper has no assurance that he is paying for permanence quality. Thus is the importance of careful specifications brought out.

∥ A list of the book papers investigated by John Burton¹³ is herewith tabulated (Table XXXV, on the following page) with the proposed permanence classification indicated in each case. This is based on chemical and physical tests on the papers. For this proposed classification, see an earlier portion of this chapter.¹⁴ According to this classification system only one of the twenty-eight papers studied could qualify as a permanent and durable paper, but several were only slightly deficient. The importance of careful processing of fibers was emphatically brought out as a result of this investigation. A fiber of initial high quality may have its purity seriously lowered by improper processing, and fibers of much lower original purity may be purified to a high degree by proper treatment.

These data serve to bring out the importance of careful specifications in the matter of permanent and durable book papers, no single test or specifications being adequate.

Conclusions for the Paper Buyer

It is easy to understand why ordinary market book papers, whether of rag, ∣📄 p.102

∣📄 p.103 chemical wood pulp, or mixture, should not be permanent papers; and emphasis has been on beauty and printability rather than on permanence and durability. Paper technologists have the formulae for papers which would satisfy the demand for permanence but such a demand has not been large enough to control market practices. The lack of agreement over specifications has made it difficult for the buyers who want permanence to exert their full weight in the market, and the small buyer can have little influence even if he knows what he wants unless he happens to want a stock commodity.

A number of specifications are included in an appended chart which gives, in addition, the properties and approximate prices of certain all-rag or purified chemical wood pulp papers, actually or potentially available.

How are these specifications to be interpreted? The paper technologists quickly draw the layman beyond his depth in the discussion, but a few facts stand out as agreed or uncontested, and upon these the publisher may safely base his policy.

(1) Fiber Content of Highest Class Papers

It is always insufficient to specify merely a source of the fibers, as, for instance, “rag” or “50% rag.” Now only should the quality of the fiber be specified but specifications covering the manufactured paper should be carefully drawn. These should include ash content, acidity, rosin sizing, alpha cellulose, copper number, folding endurance, bursting strength, and perhaps other tests depending on the use requirements of the sheet. No one or two tests alone, any more than the source of the fiber, can entirely define the permanence of a paper. For instance, some of the new fillers now being used in book papers will give a high false copper number without any other indication of impermanence. Others believe that a low alpha cellulose of rags which have been properly purified is not an index of impermanence. It is natural that the more information we have concerning the properties of a paper, the more can we judge of its general quality and usability for the purposes we have in mind.

Although it is admitted that there ∥ is no general agreement on the specifications necessary for a permanent paper made from fibers other than the highest grade of rags, the dealers and even the buying public in general have been slow to realize the need for and the significance of a permanent book paper. When the buyers specify these superior properties in a paper, the manufacturers will quote prices consistent with the specifications and the desired product will be delivered. It lies with the buying public to assist the manufacturers to keep pace with the findings of the paper technologists.

(2) Fiber Content of Second-Class Papers

Price becomes a leading consideration among the less permanent papers, and specifications do not have to be as rigid as with the first-class papers. Thus, in the Burton classification for book papers of high purity for semi-permanent records, the chemical and physical constants are ex- tended considerably beyond those for book papers of maximum purity for permanent records. The buyer should test and carefully check to specifications all papers before use in order to be sure he is getting his full money value. Again, no single test should be used as a criterion of the permanence quality of the paper under consideration.

(3) Ground or Mechanical Wood Pulp

No groundwood or mechanical wood pulp should be present in any paper designed for anything more than temporary use.

(4) Acidity

It is undisputed that high acidity causes rapid deterioration of paper. Acidity is measured in two ways: the acid number is determined by volumetric analysis and indicates the amount of acid present, while the pH value is a measure of the hydrogen-ion concentration or strength of the acid. A paper testing pH 4.5, for instance, is about 30 times more acid than one testing pH 6 and is more likely to become degraded on this account.

(5) Sizing Material

The presence of large amounts of rosin as a sizing material in paper is likely to bring about a discoloration or yellowing in papers on aging. There is general ∣📄 p.104 agreement that the rosin content of permanent papers should be kept low, probably below 1%.

(6) Fillers or Loading Materials

There is not complete agreement as to the significance of mineral fillers for permanent and durable papers. Too much material will probably reduce the durability of the sheet, but a small amount of the proper filler does no harm in the opinion of many paper technologists.

The Influence of Price

The paper buyer can be sure that any of these permanence specifications are better than none; they emphasize different elements of the paper, but they all agree in guiding the purchaser away from papers which have been manufactured (as many book papers are manufactured) without taking into account any permanence requirements whatsoever.

The publisher who is using small quantities of paper stands two steps removed from the manufacturers. The trade is organized to distribute paper from manufacturer to jobber or dealer and from there to printer. In some cases the manufacturing process is divided, one firm making the pulp and another the paper. Since the qualities which give a paper its permanence are due in large measure to the manufacture and processing of the pulp, it is especially desirable that the buyer should make a special effort to secure paper conforming to permanence specifications.

If he enters the market with some permanence specifications he will probably find his printer, and the printer’s jobber, unequipped with any tested papers. He may have to work his way back to the manufacturer. He will find that paper is sold normally in 500-pound cases, but that manufacturers will often make a special run of paper for an order as small as 1 ton (4 cases). The manufacturing and selling units are case, ton and carload (15–18 tons). The trade is familiar with the practice by which price drops as the size of the order increases to the carload; these price variations are of use in interpreting comparative pricing of paper, but of the greatest importance because they constitute an index of the size of order which will have sufficient importance to induce a manufac∥ turer to conform to permanence specifications.

The Joint Committee on Materials for Research has found some firms willing to have their paper quoted in terms of a price index. If “normal,” i.e., low-cost book paper is $.08 a pound, then these papers would be sold at the prices listed in the table. The Rag Paper Division of the Writing Paper Manufacturers! Association advises that if the base price is $.08, the price of a permanent paper meeting their specifications should be $.32. The prices named in connection with Government Printing Office specifications are those actually bid in 1932. It must be observed that this relationship in prices prevails: the “offset book” paper (not for permanent use) was bought at less than $.04, and the “permanent record book” paper at over $.16. It is evident, therefore, that large quantity orders and competitive bidding can reduce prices greatly, but the ratio between prices of papers of different qualities is not radically changed.

Under normal trade conditions the trade mark-ups and discounts should permit price variations in the following scale: (A paper selling at $.05 a pound, i.e., $10.00 a case in 2½ ton lots).

Price from Manufacturer to Distributor

Price per Case in Lots of:

The distributor’s mark-up would range from $1.60 in the one-case lots to an extreme low of $.50 to $.95 in carload lots. The printer’s mark-up should be anything from 10% to 25% of what he pays the dealer. These mark-ups do not constitute an excessive charge for the distributing service offered, nor do they greatly increase publishing cost.

How does paper cost figure into book cost? Paper is sold by the pound; a standard size of sheet is 25” x 38”; the weight of the paper is usually given as that of 500 sheets, 25” x 38”. Since a sheet of this paper will print 24 pages, 8” x 9½”, a ream will supply paper for ∣📄 p.105 38 copies. Paper weighing 45 pounds to the ream—a good stout book paper weight, as the paper samples indicate—will make up a 300-page book weighing a little over one pound. The difference between the highest and the lowest paper prices would not come to more than $.30 a volume, or less than 10% of the cost of an edition of 300. If the edition is small, the use of the most expensive paper need not greatly increase the price of the book, but may greatly increase its utility.

But most book manufacturing—practically all commercial book manufacturing—calls for larger editions, in which the composition and press charge is distributed over more copies, and the paper cost therefore proportionately higher. Moreover, the economics of the publishing business require that each book shall be printed in an edition larger than that for which there is immediate and certain sale. The chance of selling some of the overprint affords the prospect of profit. But the storage of unsold volumes increases the paper cost which must be borne by the volumes actually sold. If in an edition of 1000 books, weighing one pound each, the cost of paper is increased $.07 a pound (from $.07 to $.14) the increased cost levied upon the purchaser need not be more than $.07 a volume if the whole edition is sold; but if only 250 copies are sold, the ratable portion of the added paper cost which each must bear rises to $.28. It is the storage of valuable paper in unsold books that makes it so costly to use high-priced paper in commercial publishing. And therefore, two policies open out before those who would improve the lasting quality of books.

The first is the policy followed by the New York Times: publication in two editions; one a small edition, for relatively certain sale, printed on expensive rag paper of high durability and permanence; the other an edition for temporary consumption. But the publishers assert that in commercial publishing such a policy would introduce many new costs, not only on the press, but in storing and filling orders. The American Library Association favors the application of this policy to government documents.¹⁵

∥ The second policy is that which will be practicable as rag, purified chemical wood pulp or other papers at moderate prices prove to have satisfactory lasting qualities. The permanence level of all book papers can be raised, without greatly increasing prices. A basic economic argument helps at this point. The carefully manufactured rag papers with alpha cellulose content up to 97% can be manufactured to be more durable than a paper that merely passes the proposed Burton Class I tests. But it cannot be widely used in the publishing industry because of cost; its usefulness will lie in the small editions which do not threaten to leave their makers with a great bulk of expensive paper unsold on the shelves. The improvement of permanence qualities in the normal product of the publishing trade must depend upon the development of less expensive papers. The buyer must be induced to demand what the technicians are able to make, a rag or purified chemical wood pulp paper manufactured for permanence, and sold at a moderate price.

Preservation of Old Newsprint Paper

Whatever improvement in standards of manufacture and choice of paper may be anticipated, it cannot affect the fifty years’ legacy of inferior paper that has already been used and that now stands on our library shelves in imminent peril of dissolution. Newsprint paper is especially vulnerable. Can it be saved?

The Bureau of Standards reached a certain point in devising a method of pressing sheets of cellulose acetate into the newsprint fiber in such a way that the air was excluded and tremendous folding endurance developed. This process required no adhesives. The New York Public Library protects some of its newspaper files by covering both sides of the sheets with Japanese tissue paper, then smoothing them by running them through a heated mangle. This process has been used by the New York Public Library since 1916. Legibility is decreased somewhat, but the library feels that its experience indicates that this disadvantage is offset by the increased strength and lengthened span of life of the paper. The cost of this process is ∣📄 p.106 approximately $.08 a sheet, or $.04 a page. emis of the New York Public Library product is bound herewith. Dr. Joseph Broadman of New York City has developed a similar plan for pasting a protective transparent layer over each newsprint surface.

It is possible that the preservation of the newspaper records will not be feasible by way of the preservation of the paper, and it may be that the files printed on the most impermanent stock can be preserved only by film-copying them and letting the originals disappear. This problem will be discussed in Chapter XI in connection with the cost levels of microcopying on film. The question has already received some attention in Chapter III as a special case of reprinting material by photo-offset.

APPENDIX

The following material was not approved by the Technical Association of the Pulp and Paper Industry, but is printed herewith, not as a part of the discussion carried above, but as supplementary information offered subject to the layman’s qualms as to its accuracy.

The Scribner-Burton specifications are as follows:

EXCERPT FROM PAPER BY B. W. SCRIBNER, BUREAU OF STANDARDS, ON PERMANENCE STANDARDS FOR PAPER

In consideration of both usage of papers and the grades of papers available, it is suggested that they might be classified in four main groups according to their degree of cellulose and non-cellulose purity, as related to their service requirements. According to such mode of classification, the present domestic printing and writing papers may be grouped as follows:

Grade I. Permanent papers, having a maximum degree of purity; free from unbleached fibers, and highly lignified fibers such as groundwood. Indicative chemical properties: alpha cellulose, 90%; copper number, 1.5; rosin, 1%; acidity, 5 pH; changes on ∥ heating 72 hours in content of alpha-cellulose should be not more than 1.5%, decrease in folding endurance not more than 25%, increase in copper number not more than 0.5.

Grade II. Papers quite highly purified that may be expected to have a minimum life of 100 years; free from unbleached fibers, and highly lignified fibers such as groundwood. Indicative chemical properties: alpha cellulose, 80%; copper number, 2.5; rosin, 165%; acidity, 5 pH.

Grade III. Papers having a fair degree of purity that may be expected to have a minimum life of 50 years; free from unbleached fibers and highly lignified fibers such as groundwood. Indicative chemical properties: alpha cellulose, 70%; copper number, 53; rosin, 2%; acidity, 5 pH.

Grade IV. Papers having a low degree of purity containing considerable organic impurities, suitable for current use only. This grade includes papers containing unbleached fibers, and highly lignified fibers such as groundwood.

All figures for chemical components in these grade descriptions are upper limits, except for alpha cellulose contents which are lower limits. Alpha cellulose content and copper number are based on total cellulose content.

As stated in these grade descriptions, the purity limits are given merely as indicative and are not suggested as specification requirements, for the fixing of specification details must necessarily be done by the consumers and manufacturers directly concerned. In each of these grades, the establishment of two or more strength requirements for each weight of paper is necessary. Also, as less strength is required in book papers than in writing papers, different strength ranges are necessary for these two classes of paper. The strength requirements, of course, ∣📄 p.[106a]

∣📄 p.107 must be fixed with consideration of the kind and extent of mechanical stresses to which the paper will be subjected in its use. The strength gradations of the government papers should be of particular assistance in this respect, although as they refer to a testing condition of 50% relative humidity, they should be modified for commercial use to accord with the standard commercial testing condition of 65% relative humidity.

These specifications led the Joint Committee to interests itself in the possibility of utilizing a purified wood-pulp fiber in lieu of rag fiber where permanence is desired. In an effort to make a practical demonstration of the possible use of a wood-pulp paper manufactured for permanence, the Joint Committee received the cooperation of Dill and Collins, Paper Manufacturers of Philadelphia, and Scribners, publishers of the Dictionary of American Biography. Dill and Collins manufactured a sample lot of highly purified wood-pulp paper. This paper was used for one-third of the pages of 25 copies of Volume XIII of the Dictionary. An all-rag paper of high alpha cellulose content was purchased from the Worthy Paper Company for another third of the pages. The remaining third were printed on the paper supplied by the American Writing Company.

The alpha cellulose and copper number and accelerated aging test ∥ of these three papers are shown in the table below.

SPECIFICATIONS FOR A WOOD-PULP FIBER PAPER

These 25 copies have been placed on the shelves of the following libraries, where they will encounter different kinds of air and use. The reader is advised to examine them.

1. Dartmouth College, Hanover, New Hampshire
2. Boston Public Library, Boston, Massachusetts
3. Columbia University, New York City
4. New York Public Library, New York City
5. St. Lawrence University, Canton, New York
6. Library of Congress, Washington, D. C.
7. University of North Carolina, Chapel Hill, North Carolina
8. Public Library, Jacksonville, Florida
9. Howard Memorial Library, New Orleans, Louisiana
10. St. Louis Public Library, St. Louis, Missouri
11. Cincinnati Public Library, Cincinnati, Ohio
12. Cleveland Public Library, Cleveland, Ohio
13. Carnegie Library, Pittsburgh, Pennsylvania
14. John Crerar Library, Chicago, Illinois
15. Iowa State College Library, Ames, Iowa
16. Butte Public Library, Butte, Montana ∣📄 p.108
17. Colorado College Library, Colorado Springs, Colorado
18. University of Arizona Library, Tucson, Arizona
19. University of Southern California Library, Los Angeles
20. University of California Library, Berkeley, California
21. Seattle Public Library, Seattle, Washington
22. Toronto Public Library, Toronto, Ontario, Canada
23. McGill University Library, Montreal, Canada
24. Dalhousie University Library, Halifax, Nova Scotia

To the publisher all this complexity is reduced to two simple questions: what price shall he pay for book paper, and what weight shall he give to the rag—content specification as against other specifications, such as those stated in terms of alpha cellulose content?

Let it be supposed then that the evidence is clear and undisputed that high price alone, and rag-content specifications alone, offer no guarantee of permanence, and even though the technician soon draws the layman beyond his depth in the discussion of specifications, a few facts stand out as agreed or uncontested.

1. A paper meeting the Scribner-Burton specifications for maximum permanence, with a life probability greater than that of most of the all-rag book papers on the market, can be made without rags, from purified wood fibers.

1. A paper capable of surviving more severe tests than those proposed by Scribner, with a life probability greater than that of the best purified wood-pulp paper, can be made of new muslin cuttings.

1. The adoption and enforcement of specifications calling for either of the two papers described above would constitute an immense improvement over current practices.

The difference in permanence between paper meeting Scribner specifications and paper surpassing those ∥ specifications is an unknown quantity; a definite estimate of the price difference can be made: if permanent purified wood-pulp papers cost $.10 to $.15 a pound, then the special permanent rag papers should cost from $.16 to $.35 a pound.

Correspondence with a number of paper manufacturers has yielded the information tabulated as to papers now available on the market. The results of the tests are as given by the manufacturers themselves; they have not been checked.

Because other paper manufacturers may wish to offer papers meeting these specifications, the writer has asked the Rag Paper Manufacturers’ Association, Springfield, Massachusetts, and the American Pulp and Paper Association, New York City, to receive the names of manufacturers who may wish to offer products conforming to these specifications, and transmit them to prospective paper purchasers upon request.

The following firms are among those which will test papers to cover all the particulars of the specifications tabulated:

New York Testing Laboratories
80th Street and East Avenue, New York City

Arthur D. Little
Charles River Road, Cambridge, Massachusetts

Skinner and Sherman, Inc.
276 Sherman Street, Boston, Massachusetts

United States Testing Company
1415 Park Avenue, Hoboken, New Jersey

Bond Papers and Onionskin

Another field in which permanence is of great importance is that of bond papers, used for typescript correspondence and records of the archival type, and also in connection with the various near-print methods of reproducing text, such as mimeograph and hectograph. The general business practice of the country calls ∣📄 p.109 for a more permanent stock of paper for letters than for books, and a less permanent stock for carbon copies than for books. The average business letter sheet will last longer than the average book page; the average carbon copy will fall to pieces sooner.

As the problems of archive administration in business become better understood, it will no doubt become apparent that the carbon copies of certain classes of correspondence require more permanence qualities than the originals themselves, since they constitute the firm’s records of its own commitments. The greater part of business correspondence is systematically destroyed after a period of a few years, but for those classes of business correspondence that are intended for permanent preservation, it is appropriate to insist upon paper specifications comparable to those used for permanent record books. Onionskin papers of rag content are available, and the Eaton Paper Company has developed a line of purified wood-pulp onionskin paper. Some of their literature credits this line with 93% alpha cellulose. Test data supplied by the Brightwater Paper Company on the same or a similar line shows alpha cellulose content of 88.25, copper number 1.68, and loss of folding endurance in accelerated aging, 37%. The writer has not explored the bond paper field except in a haphazard way, but believes that in the main the technological considerations governing permanence are the same for bond as for book papers, and that the argument for using chemical and performance specifications is as good in the one case as in the other. ∥

Beauty and Legibility in Papers

The analysis of the paper situation from the standpoint of permanence has not taken into account the paper quality upon which the buyers of paper are most insistent, namely, beauty. The importance of an attractive paper in scholarly publishing is not alone its artistic contribution to the quality of a finished book, but also its relation to legibility. It has been demonstrated repeatedly that the legibility or attractiveness of a printed text is the product of many variables, such as size of type, format of page, and use of print face as against typescript letters. It is clear that paper quality also enters into legibility as an important variable. It seems quite probable that the product of the hectograph, with its light purple ink, could be made more legible and attractive if run on a yellow-ivory paper. A reader choosing between typescript and print face on a book page would have his choice materially affected if the print face should be offered on an unattractive paper, the typescript on a beautiful one. And here again a fundamental rule of small edition publishing must be respected: that because the paper cost is so small a part of the total cost, an economical place to seek for quality in the product is by using the highest class of paper. ∣📄 p.110

Notes