Acid-free paper durable acid-free paper. Archival paper is meant to be used for publications of high legal, historical, or significant value. In the USA, such paper must also be approved in accordance with the ANSI standards. The international standard for "permanent" paper is ISO 9706 and for "archival" paper, the standard is ISO 11108. Often, cotton rag paper is used for archival purposes, as it is not made from wood-based pulp. Thus, "archival paper" is sometimes broken down into two categories: Acid-free paper Acid-free paper is paper that if infused in water yields a neutral or basic pH (7 or slightly greater).
Hypochlorous acid are calcium hypochlorite and sodium hypochlorite. Solutions of hypochlorites can be produced by electrolysis of an aqueous chloride solution. The composition of the resulting solution depends on the pH at the anode. In acid conditions the solution produced will have a high hypochlorous acid concentration, but will also contain dissolved gaseous chlorine, which can be corrosive, at a neutral pH the solution will be around 75% hypochlorous acid and 25% hypochlorite. Some of the chlorine gas produced will dissolve forming hypochlorite ions. Hypochlorites are also produced by the disproportionation of chlorine gas in alkaline solutions. HOCl is a strong oxidising