Abstract: A method of casting an MFC film on a substrate (52) comprises providing an MFC dispersion having a solids content of 2.5-25% by weight, and a viscosity above 4 Pas at a shear rate of 20 s?1; exposing the MFC dispersion to a first shearing step (9), providing a shear rate of above 10 s?1; introducing the MFC dispersion into a film forming device (4), laterally distributing (41) the MFC dispersion: exposing the distributed MFC dispersion to a second shearing step (42), providing a shear rate of above 100 s?1; decelerating (43) the distributed MFC dispersion: exposing the MFC dispersion to a third shearing step (44), providing a shear rate of above 100 s?1; and simultaneously with, or subsequent to, the third shearing step (44), depositing the MFC dispersion on the substrate to form a wet MFC film on the substrate.

Abstract: A device (4) for applying a viscous liquid, in particular an MFC dispersion, onto a moving substrate (52) comprises an inlet (72, 73a-73f) for the viscous liquid, a casting chamber (61a, 61b), a lower portion of which being open to the substrate (52), and a metering portion (69, 661), for limiting a thickness of a wet film that is formed on the substrate downstream of the device. The device further comprises a shear section (42) arranged inside the casting chamber (61a, 61b). The shear section (42) comprises a fluidization rod (68), arranged in the casting chamber (61a, 61b), for providing shearing of the viscous liquid inside the casting chamber (61a, 61b).

Abstract: The present invention relates to a method for preparing a surface-treated fibrous material comprising nanocellulose, in which a fibrous material is surface treated with an organic acid or salt thereof. Fibrous materials as such are also provided. The present technology allows improved Water Vapor Transmission Rates (WVTR) for the fibrous material, while operating on an industrial scale.

Abstract: The present invention relates to a method for producing a film comprising nanocellulose, which method comprises: providing a suspension comprising 50-100 weight-% of nanocellulose based on total dry weight; forming a fibrous web of said suspension on a non-porous support; providing a press fabric comprising a web-side first surface and an opposite second surface, wherein said press fabric comprises a woven first fabric layer arranged in the press fabric as a layer providing said web-side first surface such that said press fabric has a woven surface structure at said web-side first surface; applying said web-side surface of said press fabric into direct contact with said web; wet-pressing said web by conducting said web, arranged between said press fabric and said non-porous support, through a pressing equipment, and drying the dewatered web so as to form said film. The invention further relates to a film produced from said method.

Abstract: A method of identifying a defect in a wet film comprises conveying said wet film (20), in a wet state, on a conveyor (10), providing a laser projection (1511) onto the wet film, acquiring a series of images, each depicting an area of the wet film, wherein at least a portion of the laser projection is visible, and using at least some of said images to identify said defect. There is also disclosed a method and device for producing a film.

Abstract: A method is provided for coating a fibrous web, in particular a fibrous web comprising nanocellulose fibres. The method includes steps of applying a coating agent to a textured surface region of a textured substrate, applying a fibre furnish or a wet fibrous web onto the coated textured surface region of the textured substrate, optionally dewatering to provide a wet fibrous web, and drying said wet fibrous web such that at least a portion of said coating agent is transferred to said fibrous web. The method provides a coated fibrous web with improved barrier properties.

Abstract: The present document discloses a method of determining thickness of a wet film, in particular of microfibrillated cellulose. The method comprises conveying said film (20) in a wet state on a conveyor (10) having a conveyor width, the wet film having a film width which is less than the conveyor width, providing a laser projection (1511) across a film edge, acquiring a series of images, each depicting an area of the conveyor, wherein the laser projection, a portion of the film and a portion of an exposed conveyor surface are visible, and using at least some of said images to determine at least one of a film thickness and a film thickness distribution across the film width. The document also discloses a method of forming a film, in particular a microfibrillated cellulose film, and a device for producing such film.

Abstract: A method for making a cellulose film comprising microfibrillated cellulose (MFC) is provided, said method comprising the step of: applying an aqueous emulsion of one or more vegetable oils to a surface of a casting substrate. Improved release of the MFC film can thus be achieved.

Abstract: A barrier material comprising (a) at least one layer of cellulosic substrate comprising MFC, and (b) a first barrier layer arranged on at least one surface of said cellulosic substrate, is provided, as well as a method for reducing the water vapour transmission rate (WVTR) of a cellulosic substrate.

Abstract: A cellulosic film comprising MFC is provided, which is coated on at least one surface thereof with at least one cured barrier layer. The cured barrier layer comprises CMC which has been crosslinked with a crosslinking agent. A method for improving the barrier properties of a cellulosic film is also provided.

Abstract: A method for the production of a fibrous product from a fibrous web, wherein the method comprises the steps of: providing a fibrous suspension comprising native microfibrillated cellulose, wherein the content of the microfibrillated cellulose of said suspension is in the range of 40 to 99.9 weight-% based on total dry solid content, said fibrous suspension further comprising organic acid, a metal salt or a mixture thereof, wherein the amount of organic acid, metal salt or mixture thereof is at least 2 weight-% based on total dry solid content of the suspension, —said fibrous suspension also comprising an uncharged, amphoteric or weakly cationic polymer having a molecular weight of at least 50000 g/mol, —said fibrous suspension also comprising an anionic polymer having a molecular weight of at least 10000 g/mol to said suspension, —providing said suspension to a substrate to form a fibrous web, wherein the amount of uncharged, amphoteric or weakly cationic polymer in said suspension is in the range of 0.

Abstract: The present invention relates to a method for the preparation of a nano- and/or microscale cellulose-based foam. The method comprises the steps of (i) providing a suspension (1) comprising nano- and/or microscale cellulose in an aqueous medium, (ii) simultaneously cooling and agitating the suspension (1) in a mechanical step (2a; 2b) to obtain an at least partially frozen suspension. (iii) freezing the at least partially frozen suspension (5) to obtain a substantially frozen suspension, (iv) treating the suspension under solvent-exchange (7; 8) and (v) removing the solvent (10; 13) to obtain a substantially dry foam (40A) comprising nano- and/or microscale cellulose.

Abstract: The present invention relates to a method for preparing a surface-treated fibrous material comprising nanocellulose, in which a fibrous material is surface treated with an organic acid or salt thereof. Fibrous materials as such are also provided. The present technology allows improved Water Vapor Transmission Rates (WVTR) for the fibrous material, while operating on an industrial scale.