In fact, the word kraft is the Swedish and German word for strength. Unbleached

Kraft is usually made with softwood and is used primarily in furnishes of kraft

Linerboard, wrapping paper and bag papers such as grocery bags. Semi-bleached

Kraft is used in furnishes of such grades which do not require high brightness,

Like newsprint and other groundwood-based papers. Bleached kraft is used in a

Much wider range of products than either unbleached or semi-bleached. Its greatest

Importance is in the printing and writing grades. In these grades, softwood

Kraft is used for its strength characteristics, while hardwood kraft, having shorter

Fibers, is used for its superior printing properties.

For dissolving pulp production, only acid sulfite cooking and the prehydrolysis

Kraft process are of major practical importance. Unlike paper-grade pulping, the

Acid sulfite process is the dominant system for the production of dissolving pulps,

and accounts for approximately 60% of the total production. Compared to papergrade

Production, the manufacture of dissolving wood pulp represents a niche

production. However, the high demands for cellulose purity and reactivity – as

well as its manifold routes of utilization – are the reason for its advanced state of

Technology within the pulp industry.

In this chapter, the main emphasis is placed on a comprehensive discussion of

The physical and chemical properties of dissolving pulps because they serve as

Appropriate substrates of which many aspects of pulp characterization may also

Be transferred to paper-grade pulps. The papermaking properties of pulp are

extensively described and reviewed in the relevant literature [1–3]. The following

Section on paper-grade pulp is limited to a short description of certain chemical

And macromolecular properties which are rarely presented in the literature. (The

Chemical and macromolecular properties of chemical paper pulps, however, were

Rarely the subjects of published literature. This section is therefore concerned

With a very short description of important differences in chemical and macromolecular

Properties of a selection of chemical paper pulps.)

11.2

Paper-Grade Pulp

Chemical paper-grade pulps can be categorized into hardwood and softwood sulfite

And kraft pulps. The definite differences in pulp properties between sulfite

and kraft pulps have been the subject of numerous studies [4]. Jayme and Korten

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