خلاصه ماشینی:
"Conclusion: After studying this research, the reader hopefully gains a better understanding about the damaging effects of light on archival material, preservation and conservation and how it affects archival collections.
Keywords: light, photochemical degradation, ultraviolet rays, protection, precautions, controlling measures, records, archives Archival documents are unique in nature, not only are they the only surviving copies but also they throw light on the period in which they originated.
Light, especially sunlight, direct or indirect, has a serious damaging effect on written or printed paper materials like documents, manuscripts, books, maps, sketch diagrams etc.
Rapid and serious deterioration of paper is caused by the oxidation of cellulose brought about by the ultraviolet rays in sunlight and fluorescent light.
Photochemical deterioration of paper means conversion of cellulose of the paper into oxycellulose due to a chemical reaction produced by light particularly ultraviolet radiation because the main component of paper is cellouse.
It is evident that the control of light is necessary in the places like archives, museums and libraries where manuscripts, documents, books, maps, diagrams, paintings, executed on paper etc.
Precautions to control the invisible but photochemical active ultraviolet rays of light: Sunlight should be preserved from falling directly on paper because the sun is a great emitter of ultraviolet rays.
Special glass containing cerium and cobalt oxides affords very effective protection to written as well as printed papers by minimizing the entrance of ultraviolet rays to greater extent than even lemon yellow or green colored glasses."