«Deteriorating Paper in Sweden A Deterioration Survey of the Royal Library, Gothenburg University Library, Uppsala University Library and the National ...»
In the processing of the results we chose not to weigh the categories paper, binding and cover against each other as was done with the library materials. The reason again was the character of archival collections with some of the materials bound in volumes and some kept in boxes. Thus all graphs display the results of the paper-testing, P-values, which can be directly compared with the results from the libraries.
As can be seen in the next graph (Fig. 7) the amount of P 3 is almost the same as in UUB and KB. The amount of P 2 on the other hand is 31%, which is far more than in either of the libraries. Probably the P 2 has increased at the expense of P 1, the reasons for this possibly being more tears, worn edges and "dirt" through extensive use or a higher degree of air pollution, which gives the paper a yellow tone around the edges.
Books often come directly from a publisher or a book store, brand new, and they may never be used after being put on the shelves. The condition for being defined as archival records is that they be a product of an administrative process. Thus this material has been used and is consequently more worn and dirty. Paper in such a condition cannot be graded P 3 if it does not break when folded, but on the other hand it is not in such a good condition as to be classified as P 1. This paper ends up in P 2. It is highly probable that there is some reciprocity between P 2 and P 3. When the P 2share increases, the P 1 decreases as the grading is in fact a choice between P 1 and P 2, unless the paper breaks and is graded P 3.
There were some difficulties in making a graph of the P-values' spread over time and put into relation to the total number of sheets tested (Fig. 8) as many of the documents were difficult to date exactly - books have an exact year of publication. 15% of the documents tested at RA were therefore excluded from this graph. That is probably why there are such fluctuations in the total number of sheets tested. The number of papers tested from the 1950's and onwards decreases, which probably is due to the delay in the deliveries of archival records from different authorities.
As in UUB and KB, P 3-values are high in proportion to the total number of sheets from the 1860' to the 1890's. P 3 shows an increase during the 1920's while the total number of sheets decreases. This effect has no equivalent in the results from the libraries.
CONCLUSIONS OF THE STANFORD SURVEYThe main conclusion from the surveys made at UUB, KB and RA is that the greatest share of paper in bad condition, in proportion to the total amount, is from the later half of the 19th century. This is clearly visible in Fig. 9, which shows the average of the total amount in proportion to the average of P 3 tested at the three institutions. By making a graph based on average figures, individual variations become less prominent, presenting a more balanced picture of the condition of the examined collections.
Fig. 9. Average distribution of the total amount of samples No. of samples and P 3 at UUB, KB and RA.
We Ivar Hoel says in his report, Papimedbrydning, that the books with the most deteriorated paper, and which should thus be mass treated, are from the period 1880-1970. 5 This statement is based solely on pH-measuring.
Fig. 10 shows Hoel's pH-results for Swedish books. According to this the papers with the lowest pH are from the 1950's. According to Hoel's reasoning, this should be the most deteriorated paper.
Hoe!, Papirnedbrydning, p. 90.
Ivar Hoel states that bad paper has a lower pH than good paper. In the chemical analyses that were done on the paper samples at UUB to establish if that and other hypotheses on paper quality coincided with the results of the Stanford method, we found that paper falling within the P 3-category also had the lowest average pH of the three grading categories. The authors find it strange, considering this, that Hoel reports a steady increase of paper in bad condition, from the 1880's and forward in time, while the results in this report show that most of the deteriorated paper is from the 1860's to the 1890's. After that period the amount of paper in bad condition decreases while the amount of paper in good condition increases rapidly up to the present.
The graph showing the average percentage distribution of bad paper from UUB, KB and RA (Fig. 11) also shows the same results from a survey made at the Yale University Library, which we have chosen for comparison. 6 36,500 volumes were tested in that survey to get the highest possible statistical validity. Apart from the amount of deteriorated material, the Swedish curve and the Yale curve follow the same pattern.
One can expect that the bulge in the latter part of the 19th century will move forward but the speed and amount is dependent on the initial quality of the paper and the preservation environment.The reasons for Hoel's divergent
results are the following, among others:
-The results of Ivar Hoel's survey is solely based on pH-measurement without putting the pH in relation to the physical properties of the paper.
-The sampling methodology has been manipulated by repeatedly directing the choice of the sample, largely vitiating its randomness.7
-The way the pH-measuring was done offers many pitfalls, among other things precision has been sacrificed in favor of rationalized and less time-consuming measurement. 8 This can explain the extraordinarily low pHvalues Hoe! reports. 9 Considering the emphasis Hoel places on the importance of pH, this leads to serious consequences for the value of the entire survey.
Conclusions regarding the state of the collections in the Nordic countries in about 40 years' time seem particularly risky under such circumstances.
9Compare 33% pH 2 in Library of Congress, Hoe!, Papirnedbrydning pp. 101, with 2% pH 2 in Library of Congress, OTA, Book Preservation Technology, Fig. 2 P. 14.
One merit in the work of Ivar Hoe!, though, is that he has drawn attention to the importance of climate on the deterioration of paper, which ought to be an important issue when discussing mass conservation.
THE COMPARISON BETWEEN UPPSALA AND GOTHENBURG
UNIVERSITY LIBRARIESThe P-values at UUB and GUB The survey done at the Gothenburg University Library (GUB) was not intended to show the actual state of that library collection but rather how different preservation environments might affect specified objects. Thus exactly the same editions of the books studied in the UUB survey were tested at GUB. 184 of the 384 books tested at UUB could be found in the GUB collection. It may seem that this is not a sufficient number to make the results reliable, but since it was a question of direct comparison between defined objects, we considered the material to be large enough to give us results on similarities and differences.
Fiber content, type of sizing, lignin content and pH were already known from the chemical analyses made at UUB. This made it possible to make a more thorough comparison. It was also possible to compare Pvalues from the two university libraries with the chemical properties of the papers.
The distribution of the P-values showed that the differences between the libraries were minor (Figs. 12 & 13).
The P-values and their Relation to the Chemical Properties of Paper When the P-values for individual objects were compared, there were some discrepancies. A P 1 in UUB could have changed to P 2 in GUB and vice versa.
Hypothetically, discrepancies in categorizations might be due to special caracteristics of the papers, on the one hand, while those given the same value might have other qualities in common.
Fig. 14 below shows the different chemical properties analyzed and their distribution in different P-grading combinations.
The graph shows on the left side the chemical properties of the paper and the perpendicular columns represent the different P-grading combinations.
The different P-grading combinations are formed on the following basis.
UUB 184 vol. This column shows the results of the chemical analyses performed at UUB, on the 184 books also available at GUB.
Similar P 1-value. This column includes all objects with P-value 1 both in UUB and GUB, i.e. paper in good condition.
Similar P 3-value. This column includes all objects with P-value 3 both in UUB and GUB, i.e. paper in bad condition.
P1 to P 2. Includes all objects with P-value 1 in UUB which got Pvalue 2 in GUB or vice versa. This group consists of either heavily used paper or/and chemically decayed paper in worn condition.
P 1 to P 2, rag excluded. The column consists of all objects given a P-value 1 in UUB and P-value 2 in GUB or vice versa. All rag papers in this group were excluded. This group consists of paper with no rag content, either heavily used or/and chemically decayed and in worn condition. This group acts as a support for the theory that many rag papers, usually of good quality, end up in this group due to the "unfavorable appearance" of these papers.
P 1 or P 2 to P3. Consists of all objects given a P-value 1 or 2 in UUB and P-value 3 in GUB or vice versa. This paper is highly unstable and very susceptible to damage due to handling and the preservation environment.
All changed P-values. Consists of all objects with a different grading in UUB as compared to GUB.
All unchanged P-value 1 and 2. Consists of all objects given the same P-value in both UUB and GUB. The column includes paper of good or worn quality. The paper graded P 2 in this group was probably graded P 2 more due to its worn appearance than its being chemically degraded.
Comments on chemical properties of paper.
Alum rosin size. The paper in 85% of the 184 books were rosin sized. Alum rosin size was especially prevalent in the following P-grading groups: "Similar P 3 value", "P 1 or P 2 to P 3" and "All changed P-values".
Lignin. In the total sample 21 % of the examined papers contains lignin. In the P-grading group "P 1 or P 2 to P 3", the lignin content increases up to 43%. A look at the papers having the P-grading good/worn quality (P 1, P 2) reveals that these papers contain only 15 % lignin.
Paper Fibers. Rag fibers are prevalent in the P-grading group "P1 to P 2" but are lacking in the group "P 1 or P 2 to P 3". The latter is quite natural as the P-value 3 represents the really inferior paper quality, all according to the folding-test. More surprisingly, the rag content is high in the P-grading value 2 as this group represents worn paper while rag fibers usually mean a paper of good quality. It is highly probable that a great number of the papers containing rag end up in the P 2 category. The reason for this can be that rag papers can have a yellowish tone and sometimes a structure that gives the impression of a worn paper to the untrained eye (the whole point of the method is that the amateur should be able to carry out the grading). The criterion for a P 2-grading is that one or many of the following attributes can be observed in the paper.
Tears - a few Edges - somewhat worn Yellowing - slight 6 foldings - no breaking or tearing When grading a paper like this, the survey member has to make a choice where it is impossible to grade the paper P 1, all according to the above-mentioned grading criteria. It is also impossible to grade the paper P 3 because the paper does not break after the folding test. When these two possibilities no longer exist, the paper ends up in P 2. In this way the P 2grading contains a larger proportion of good quality paper than one might expect. Hence the true nature of the P 2 value will not appear until the rag papers are excluded. This can be clearly seen from Fig. 14.
pH. The average pH values in Fig. 14 correspond to what could be expected from the P-grading groups.
Groundwood - An Unstable Paper Fiber that is Sensitive to Different Environmental Conditions Fig 14. shows that the P-grading groups containing groundwood are more prevalent in the P-grading groups with inferior quality paper. Pure groundwood is not represented in the total GUB-sample. One explanation for this could be that it is not common to use pure groundwood in the types of publications examined, i.e. monographs (in the UUB-sample of 384 volumes only 2 contained pure groundwood). In the P-grading group UUB 184 volumes 15 % consist of groundwood+chemical pulp whereas in the group "P 1 or P 2 to P 3" 29 % contain grounwood+chemical pulp. The better paper quality in "Similar P 1 value" contain only 8% of this fibermixture. The fiber combinations 5, 6 and 7 were examined to see if these fiber combinations containing groundwood would show any difference in Pvalues between UUB and GUB.
The P-values of UUB were as follows:
P 157% P216% P327%
The P-values of GUB were as follows: P 143% P216% P341%
In this case there is a clear difference between P 1 in the libraries, 57% and 43% respectively. P 3 show an even clearer difference, with 27% and 41% respectively. This means that these fiber combinations are more decayed in Gothenburg than Uppsala. There is no difference in P 2 and if one accepts the theory that P 2 means a paper damaged due to rough handling, this means that the difference between the two libraries is mainly due to the environmental conditions. Further investigations on the differences in environment in Uppsala and Gothenburg would be extremely valuable. The effect of the environment on paper has been documented. 10 Investigations of this kind could gain in value if they were connected specifically to papers containing groundwood, as our findings imply that groundwood paper is highly sensitive to different environmental conditions.
Aldring/nedbrytning av papper, p. 56.
REFERENCESBuchanan, S. & Coleman, S., Deterioration Survey of the Stanford University Libraries Green Library Stack Collection. Preservation Planning Program - Resource Notebook, June 1979, ed. Darling, P.
W., Washington, D.C.1982.
Hoel, I. A. L., Papimedbrydning - en undersøgelse af papirsurhed og papirstyrke i nordiske bØger 1850 - 1985. Det kongelige bibliotek, Forskningsrapporter 1, Kobenhavn 1987, ISSN 0902-8714.