Principles of Coating Techniques for Paper and Board

In principle, coating can be divided into different phases  

Coating can be done double-sided, i.e., both sides of the paper are coated simultaneously (e.g., MSP), or on only one side at a time. Printing papers are usually coated similarly on both sides, and boards often on one side only. 

Pigment is the most abundant component in the coating, so pigment is naturally the most important factor affecting the properties of the coating (see also Section 2.2.2). An ideal pigment would have the following properties  

There is of course no pigment that could meet all these requirements, however, different pigments meet different combinations of them. The main coating pigments are clay (kaolin), ground calcium carbonate (GCC), precipitated calcium carbonate (PCC) and talc. 

Among binders, styrene-butadiene latexes dominate beside modified starches. Styrene-acrylate dispersions are spedalties and of high importance for impressive prints. Additionally acrylate dispersions have an excellent brightness and ageing resistance and are less odorous. Future requirements of coating process conditions, on paper characteristics and printing technologies forced the production of tailor-made binders with very specific property profiles. 

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