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There is a chemical used to clean dry ink and dirt accumulated on the paper documents when stored for long periods - or chemical structure (raw materials that go into the chemical composition). Bearing in mind that it does not permanently affect the original documents and publications because it has been the use of thermal ink to print !
In the production of white paper, the wood pulp is bleached to remove any color from the trace amounts of lignin that was not extracted in the chemical pulping process. There are three predominant methods of bleaching:
I thought it is cl or na2co3
