Printing and writing paper

The pulp and paper industry produces primary products—commodity grades of wood pulp, printing and writing papers, sanitary tissue, industrial-type papers, containerboard, and boxboard— using cellulose fiber. The two steps involved are pulping and paper or paperboard manufacturing. 

The pulps obtained from chemical pulping are brown in colour and, whilst suitable for many applications, are unsuitable for printing and writing papers which require a bright white pulp. Both chemical and mechanical pulps often require bleaching for many end uses. The colour of these pulps is mainly due to residual lignin ( 3—6%, see Table 2.2 in Chapter 2) although products derived from carbohydrate may also make a contribution. The approach to removal of colour is different in each case. 

Printing (JCP) provides specifications for printing and writing papers used throughout the federal government. 

Paper specimens were obtained from Mead Paper, Printing and Writing Paper Division (Chillicothe, Ohio 45601). Samples were identified as being free from other materials, i.e., no preservatives, slimicides, defoamers, etc. Internally-sized samples were sized by conventional alum/rosin sizing surface-sized materials were prepared by an application of starch at the size press and all the other samples were unsized. Whatman filter paper was extracted with a 68/32 mixture of chloroform/acetone to remove any organic binder from the fiber surface. The fiber composition of the Whatman filter paper was identified by optical microscopy as cotton. The sample identified as "No Sizing" was... 

One of the true arts, still practised in papermaking, is the colouration of paper. Chapter 10 covers this subject with great delicacy. Explanations are given of how colour is perceived by the human eye and how differences in shade are distinguished. The chemistry of various chromophores is discussed as well as the conditions under which these chemicals are best used e.g. acid dye use in crepe paper, basic dyes in newsprint and direct dyes in printing and writing papers. 

Anionic direct dyes are the most widely used colourant within the tissue, printing and writing paper sectors. Having a typical molecular weight of 550-2,000, they produce a wide range of shades, although certain bright shades cannot be achieved... 

Chem. Descrip. Rutile titanium dioxide CAS 1317-80-2 EINECS/ELINCS 236-675-5 Uses Opacifier, pigment in paper coatings, coated and uncoated printing and writing papers, paperboard, saturating papers Regulatory DOTnonregulated SARA 311/312 nonreportable CERCLA nonreportable... 

Thus, the overall objective of this chapter is to introduce the concept of PCC-NFC composites to construct a novel and improved printing and writing paper by modifying or blending the structural elements of cellulosic pulp fibres and pigments, and to study the forming process and product properties. 

The objective of the following study was to investigate the impact of PCC-ceUulosic fibril composites, described earlier in Sect. 5.2, on conventional printing and writing paper. 

In 2002 graphic papers accounted for 43% of total paper production. This included newsprint (37 x 10 t) and other printing and writing papers (104 x 10 t). The production of packaging papers was 153 x 10 t, and that of the remaining papers and boards was 37 x 10 t (Table 1.5). 

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