Paper Scientific Developments: Increase of paper permanence by treatment with liquid ammonia or ammonia solutions: Part 1, Fundamental basis and influence on fibre and paper structure and properties
| Main Authors: | , |
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| Format: | Article |
| Language: | English Slovak |
| Online Access: | http://www.viks.sk/chk/conservation_book_31_36.doc |
| Abstract: | Summaries. The brittleness of paper as a consequence of natural or accelerated ageing is at least partly due to cross-linking of the cellulose and hemicellulose chains in the fibre walls or in the region of fibre-fibre-bonds. A treatment with liquid ammonia or with concentrated ammonia solutions should cause changes in the supermolecular structure of the fibre and in effect reduce the area capable of cross-linking or break already formed crosslinks. Test sheets made from bleached wood pulp were treated with liquid ammonia at - 50°C resp. with 55 to 75% solutions at -20°C, before and after accelerated ageing at 90°C and 70% RH. The folding endurance of pretreated test strips declines to a very much lesser degree than that of untreated specimens. Ammonia treatment after accelerated ageing causes significant increase in the folding endurance and the brightness. In both cases the properties of the paper in respect to 'usability' were significantly improved by the ammonia treatment. |
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| ISBN: | ISBN 0-408-01466-0 |
