Paper permanence

We also expect our business partners -paper mills, printers, packaging manufacturers, etc. - to commit themselves to using materials and production processes that do not harm the environment. The paper in this book is made from low- or no-chlorine pulp and is acid free, in conformance with international standards for paper permanency. 

The question of paper permanence is concerned primarily with the stability of cellulose fibers. Pure cellulose in its native state is a very stable material. Cellulose textile fibers have been preserved under favorable conditions for long periods without loss of integrity. It has been observed that many papers manufactured 100 to 200 years ago from cotton or linen fibers have retained their essential usefulness. 

B. The extractable pH of many well-washed photographic prints has been in ihe range of 5.5 to 6.0 (only a medium permanence level by ASTM Specification D-3290-74), but well-washed photographic prints have endured for many years. Estimates of paper permanence based upon rates of change at several elevated temperatures assess the overall effect of degradative reactions and resistance to those reactions, including the effects of acidity. 

Folding endurance under tension (10) is a favorite physical property for research on paper permanence and is the basis for the TAPPI method (16). Application of the mechanism involved in this test procedure, however, is unknown in practical uses for paper. Comparisons among product choices and estimates of their useful life should be based upon tests that assess physical properties of practical interest. Retention of reflective brightness, tear strength, tensile energy absorption, and... 

If the oxidation rates observed by DTA are assumed to be a valid measure of paper permanence, the technique can be very useful. The relative effects of trace metals, pH, antioxidants, and other nonvolatile... 

The rankings and the relationships between them indicate that the activation energies obtained are mainly influenced by chemical reactions —e.g., levoglucosan formation and breakdown—which are not closely related to those chemical reactions involved in determining paper permanence. The earlier hydrolysis reaction which most likely is correlated with relative permanence characteristics does not sufficiently influence the value of activation energy obtained, even at the lowest extent of reaction used in this study. On the other hand, these early reactions do... 

Many conservation treatments have been devised to slow down the rate of deterioration of paper. Often these treatments neutralize excess acidity in paper, which is an important factor in paper permanence. The probability of success with a new method is often determined by the use of accelerated aging tests and also by drawing parallels with existing methods thought to be effective. Many studies have investigated the best conditions for accelerated aging tests, but disagreement between laboratories is often found. However, even the best set of conditions produces a distortion of the results that would have occurred in ambient conditions. 

Resins used as water repellants, stiffeners, or wrinkle resistors Paper products Paper towels Grocery bags Waxed paper Permanent press clothing Carpeting Linoleum Plastics Drapery... 

Zou X, Uesaka T and Gurnagul N (1996), Prediction of paper permanence by accelerated aging 1. kinetic analysis of the aging process . Cellulose, 3(4), 243-267. 

The rate of change for all the physical properties investigated in this study increased proportionately with the amount of moisture in the aging atmosphere at each of the temperatures studied. Unquestionably moisture has a profound affect on the degradation rate of paper and is perhaps the most Important environmental variable to be considered in studies of paper permanence. 

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