Paper & pulp

The European paper industry uses recycled content in many of its products. But before mills can make use of postconsumer recycled paper, it must be deinked to improve brightness. Ink content as a percent of furnish weight is typically 1.5% to 2% for newspapers and 1% to 7% for magazines. A major deinking method proven over many decades involves froth flotation with soap-calcium chemistry.
Calcium chloride (CaCl2) provides the calcium ions needed to effectively adjust water hardness during the deinking of secondary fiber at paper mills and paper recyclers for use in recycled newsprint and other papers.

Furthermore, magnesium hydroxide is used as a coating agent for paper.