Stora Enso Oyj

Other

Stora Enso Ab

Stora Kopparbergs Bergslags Aktiebolag (publ)

Frank Peng

Anders Moberg

Isto Heiskanen

Seppo Lampainen

Mats Fredlund

Atso Laakso

Ari-Pekka Määttänen

Kaj Backfolk

Teija Laukala

Gunilla Pettersson

Sven Norgren

Hallgren Hans

Hans Höglund

Mika Riikonen

Fredrik Werner

Hans Hallgren

The invention relates to a ply of a linerboard for corrugated board, which ply exhibits high strength properties and which enables the production of lightweight linerboards. The ply of the invention comprises 20-80 wt % CTMP from wood fibers and 80-20 wt % chemical pulp, calculated on the total fiber weight of said ply and strength additives chosen from the group of microfibrillated cellulose (MFC), anionic or cationic polymers and starch or combinations thereof. The ply exhibits a geometric SCT index of above 22 Nm/g and a density of below 680 kg/m, preferably of below 650 kg/m.

Ply of a linerboard and a light weight linerboard for corrugated board

The invention discloses a paperboard comprising a base ply, a top ply, and an intermediate layer disposed in-between the at least one base ply and the top ply. The intermediate layer comprises pigment and microfibrillated cellulose (MFC). The application of an intermediate layer comprising pigment and MFC in-between the base ply and the top ply gives rise to improved optical properties of the paperboard, even when using an uncoated top ply having a low grammage This makes it possible to reduce the grammage of the top ply and still obtain good optical properties.

Paperboard and a method of producing a paperboard

The invention relates to a lightweight linerboard for corrugated board with good strength properties and which reduces problems with washboarding in the thereof produced corrugated board. The linerboard of the invention comprises at least one ply comprising 20-80 wt % CTMP from wood fibers and 20-80 wt % chemical pulp, all percentages calculated on the total fiber weight of said first ply, wherein the CTMP exhibits a bulk of at least 2.5 cm/g.

Light weight linerboard for corrugated board

The present invention relates to a process for producing at least one ply of a paper or board product wherein a web comprising mechanical and/or chemimechanical pulp and at least one dry strength additive is dried in a press drying process by subjecting the web to heat and an overpressure of above 40 kPa. The present invention also relates to a paper product, a paperboard product and a ply produced according to the process.

Process for producing at least one ply of a paper or board and a paper or board produced according to the process

The invention relates to a high quality paperboard comprising at least two plies, a first ply having good surface properties and strength, and a second ply for providing the paperboard with bulk wherein the second ply comprises hardwood CTMP. This paperboard has an internal strength and a bending resistance that is comparable with conventional high quality paperboard based on softwood CTMP. The invention also relates to products manufactured of the paperboard.

High quality paperboard and products made thereof

A method in connection with the production of mechanical pulp from a cellulose containing material wherein the material is processed in at least one refining step to produce pulp. According to the invention, the pulp is fractionated (), after a first refining step (), in order to separate primary fines () from the pulp. The invention also relates to a mechanical pulp, produced by the method, and to a paperboard, which at least partly consists of such mechanical pulp.

Method in connection with the production of mechanical pulp

Method for manufacturing paper or cardboard in one or more plies in order to achieve a paper or cardboard product with an even quality. The method comprises determining a fiber composition of a broke paper or cardboard waste broke, fractionating the broke; and conveying at least one fiber fraction obtained thereby to a given ply in the paper or cardboard. In this way the fractionating is controlled so that the fiber composition in the fiber fraction obtained corresponds to a fiber composition in the input paper pulp for the given ply.

Growing community of inventors

Hammarö, Sweden

Frank Peng