Photoinduced discoloration

Figure 4. Direct photoinduced discoloration of modern paper...

To effectively prevent photoinduced discoloration of modern paper, one must consider the environment in which it may be stored, exhibited, or used, and the causes of its yellowing. In view of the photochemistry involved, some form of photostabilization of modern paper is essential if adequate protection against the detrimental effects of solar irradiation is to be achieved. 

Principally, the photostabilization of modem paper involves the retardation or elimination of the various photophysical and photochemical processes that take place during photoinduced discoloration. This goal may be accomplished by the following three stabilizing systems. 

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