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The Uncoated Mechanical Market

These are the grades used to print phone books, newspaper inserts, low quality magazines, catalogs and a host of other applications where the life of the print is short, but the quality of the image must be good. These papers are printed by rotogravure, offset and flexographic printing (which is replacing letterpress). The paper must be smooth, low cost and print well. High levels of pigment can be used and until recently the dominant pigment used was kaolin. More recently in an attempt to lower cost and achieve higher brightness levels pseudo-neutral papermaking and carbonate pigments have been used more frequently. Even then kaolin is a key pigment in order to achieve the level of smoothness and porosity that is best for a good print. Mechanical fiber is the majority of the fiber used in these grades. They are used for their high opacity, low cost and compressibility for rotogravure printing. Platy kaolin pigments like Intramax, Capim CC, Capim SBF, Astrafil 1900 and WP are commonly used as either the only pigment or as a partner to carbonate.

Newsprint We are all familiar with newspapers. This printing medium is one of the shortest lifetime printing mediums around. Cost must be minimized in producing these grades. Mechanical fiber is used for the same reasons it is used in the other mechanical paper segments. Newsprint is printed in a variety ways including letterpress, flexographic, cold set offset and rotogravure. The strategy for producing the grade varies by region of the world and by sub-region. This can mean that the way newsprint is made in Canada can be different from the way it is made in the Southern US and they both can be different from how newsprint is made in Japan. Some newsprint is made with a light pigmentation in Japan and these grades are referred to as Bitoko. These grades might use carbonate and/or kaolin type pigments for surface treatments. In the Southern US the control of pitch is very important to keep productivity at a high level. Basis weights are decreasing in the US and so opacification and ink strike through are very important. This is best achieved with calcined clay grades like Opacitex, Alphatex and Alphatex HP. Other regional areas may have similar problems and calcined clay is used in some mills in Northeast Canada as well as in Australia. In Europe filler clay is commonly used such as Intrafil B and Intrafil C. To further illustrate the importance of cost as well as performance; in the Western US PCC is commonly used in newsprint to control the opacity and ink strike through. Scalenohedral fillers like Opti-Cal HP are used in this application.