What is the name of the chemical used in the cleanup of paper documents of inks that are falling out when stored for long periods ?

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:

1. Elemental chlorine bleaching uses chlorine and hypochlorite.
2. Elemental chlorine-free bleaching is more environmentally friendly since it eliminates the use of hypochlorite and replaces chlorine with chlorine dioxide or sodium chlorate.[3]
3. Totally chlorine-free bleaching utilizes oxygen and hydrogen peroxide. This is the most environmentally friendly process since it eliminates all chlorinated pollutants.[4

I thought it is cl or  na2co3