Paper and Board Applications

The use of starch in papermaking is probably one of its oldest non-food applications. An old Egyptian paper document dating from 3500 bc shows that starch was already used for sizing. Starch as a sizing agent was also used in China, as documented by a paper document dating from ad 312 that was sized with starch. 

After fibres and fillers, starch is still the third most important raw material for paper making. Various types of modified starches are applied throughout the papermaking process from the wet-end via the size- or film-press to coating and paper converting. 

The next phase consists of the removal of the water by hydrodynamic and suction devices. When non-cationic starches were still used during this process, the majority of it (70% according to some authors) would be lost to the wastewater. On the other side, when a suitable cationic starch is used, then over 90% of it stays with the paper web. 

Unthinned, cooked cationic starch is added to the fibre as a dilute solution (normally far before the headbox). 

A solution of thinned, cooked starch is applied to the paper web. The viscosity and concentration are adjusted to produce optimal penetration and runnability. 

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Water-based adhesives are applied as aqueous solutions, dispersions or emulsions and are used mainly in paper and board applications, for example, side-seaming of cartons. Typical examples of adhesives applied in this way... 

Mississippi Lime Co. has designed Magnum Gloss for use in glossy, high brightness coated paper and board applications. 

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