Nordkalk Oy Ab

Basf Se Corporation

Sakari Saastamoinen

Pentti Virtanen

David Robert Cordier

Teemu Gronblom

Lars Gronroos

Tero Seppala

Christian Bruce Edmonds

Teemu Grönblom

A precipitated carbonate polysaccharide structure which, when used as a filler, improves the structural strength of paper or board, or gypsum boards, plastics or gums, among others, as well as the stiffness level and optical properties (brightness and opacity) of the paper or board, together or separately with other fillers; carbonates, in particular. The invention further improves the setting of printing ink on the surface of the paper or board. The invention also includes the manufacturing method of the precipitated carbonate polysaccharide structure.

Manufacture and use of a composite structure containing precipitated carbonate

The present invention relates to a method of manufacturing paper or cardboard, wherein paper or board pulp is diluted with an aqueous composition, which is formed from colloidal-size particles of carbonate and bicarbonate, and other states of carbonate in an aqueous solution, so that the pH in the aqueous solution remains essentially at a value of 6.0-8.3 during the formation, and water is removed from the pulp by draining, pressing, and drying. The invention also relates to a method of manufacturing the aqueous composition used for this purpose.

Use of acidic water in the manufacture of paper

The present invention relates to a process for manufacturing paper or board, wherein paper or board pulp is diluted with acidic water and wherein the pH value of the pulp is raised with an alkali simultaneously with increasing the solids content of the pulp by filtration, compression and evaporation on the wire, press and drying sections, and, at the same time, filler is precipitated from the acidic water into the paper or board structure. The invention also relates to moistening of paper or board, with a dry matter content of over 40%, in acidic water, after which the pH value is raised with an alkali, and the paper or board is dried, or it is dried after the moistening without raising the pH value.

Process for manufacturing paper or board

An aqueous polysilicate composition comprising a polysilicate microgel based component in association with particles derived from colloidal polysilicate. The invention also concerns a process for preparing an aqueous polysilicate composition comprising mixing an aqueous colloidal polysilicate with an aqueous phase of a polysilicate microgel. The aqueous polysilicate composition is more effective than colloidal silica and is more stable than a conventional polysilicate microgel.

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Hameenlinna, Finland

Sakari Saastamoinen