M-real Oyj

Soili Hietanen

Markku Leskelä

Petri Silenius

Maija Pitkänen

Teuvo Ilmonen

Outi Aho

A filler comprising cellulose or lignocellulose fibrils on which light-scattering material particles have been deposited, and a process for the manufacture thereof. In the filler according to the invention, an alkyl derivative of cellulose, such as CMC, has been sorbed to the fibrils. Such a filler can be prepared from a source material containing cellulose or lignocellulose fibrils by first forming a fibril suspension, into which there are fed source materials forming an inorganic or organic salt that, when precipitating, forms a light-scattering pigment. The filler according to the invention has very good strength properties; in particular, good bond strength is achieved by means of it. The concentration of mineral pigment in paper can be increased and, furthermore, the grammage of paper can be lowered without the other important properties of the paper deteriorating.

Filler and a process for the production thereof

The invention relates to a method for producing a calendered paper web. According to the method, a paper web is formed from a fibrous raw material in a paper machine, and the paper web is calendered. According to the invention, a fibrous raw material is used which is at least partly made up of a chemimechanical pulp of a species of thefamily, and the calendering is performed by online soft-calendering. By means of the invention, the gloss and smoothness of papers can be improved without decreasing their bulk.

Calendered paper product and method of producing a calendered paper web

The invention relates to a process for producing a coated paper web, According to the process, a paper web is formed from a fibrous raw material in a paper machine, the paper web is coated with a pigment-containing coating mix, and the coated paper web is calendered. According to the invention, the paper web is coated with a coating composition that contains as the mineral pigment mainly a mixture of gypsum and calcium carbonate, the amount of gypsum being at minimum 10% by weight of the total amount of gypsum and calcium carbonate. With mixtures of calcium carbonate and gypsum, such as mixtures of PCC and gypsum and mixtures of PCC, ground carbonate and gypsum, there are obtained simultaneously a sufficient gloss and smoothness as well as a brightness and opacity better than with PCC-kaolin pastes.

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Espoo, Finland

Soili Hietanen