M-real Oyj

Other

Markku Leskelä

Antti H Rahtu

Petri Silenius

Soili Hietanen

Maija Pitkänen

Jyrki Kettunen

Esa Torniainen

Teuvo Ilmonen

Kaupo Kukli

Mikko Ritala

Sami Haapala

Jari Meuronen

Kai E J Vikman

Pirita Suortamo

Marko Pekkola

Isto Nikamaa

Ole Nickull

Kristiina Manninen

Auli Laurila-Lumme

Method for the production of mechanical or chemi-mechanical pulp as raw material for paper or cardboard. According to this method, the pulp is fibrillated and the fibrillated pulp is bleached in alkaline conditions. According to the present invention, the pulp is screened to separate the reject from the accept, at maximum approximately 60% of the total amount of pulp is separated as the reject, the reject is bleached separate from the accept, and, after that, the bleached reject is remixed with the accept. When operating according to the present invention, the strength of the pulp increases and the energy used for refining is reduced, which is seen both in the refining of the reject and in the post-refining of the final mechanical pulp.

Process for producing mechanical pulp suitable for paper or cardboard making

This invention concerns the production of a multilayer fiber product. According to the method, on top of a bottom layer consisting of at least one fiber layer, a second fiber layer is fitted containing filler that forms the surface layer. According to the invention, the layers are formed by multilayer web forming technology, and the surface layer filler includes cellulose or lignocellulose fibrils, on which light-scattering material particles are deposited, having a maximum proportion of the total filler weight of 85%. By means of the invention, a base paper is achieved that is suited to thin, coated paper grades, where conventionally the intrusion of the coating color into the bottom paper and through it is a problem.

Method for producing fiber product

A method is provided for growing thin oxide films on the surface of a substrate by alternatively reacting the surface of the substrate with a metal source material and an oxygen source material. The oxygen source material is preferably a metal alkoxide. The metal source material may be a metal halide, hydride, alkoxide, alkyl, a cyclopentadienyl compound, or a diketonate.

Method for growing thin oxide films

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

A method for producing printed products, according to which method the surface of a sheet of paper or board is printed by the electrophotography technique or a similar printing method, wherein a dry finely-divided printing ink is transferred onto the printing base by means of an electric field. According to the invention, a paper or board is used the printing surface of which has a pigment-containing coating layer in which at least 20% of the pigment is made up of a hydrous pigment, such as gypsum, or in which at least 20% of the filler is made up of a hydrous filler, such as gypsum. When a gypsum pigment and/or a gypsum filler is used, the quality of the printed image is not sensitive to the control quantities used in the printing press. By means of the invention, a very regular print is indeed obtained, and so the invention is especially well suited for the printing of a sheet of a very matt paper or board.

Method of producing printed matter

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.

Process and coating composition for coating a paper web

Growing community of inventors

Muijala, Finland

Markku Leskelä