A curtain application unit for applying a liquid or pasty application medium to at least one surface of a moving material web, in particular a fibrous web, includes an application head having at least one separation edge extending substantially over the width of the application head. The application medium exits the application head in the form of a free-falling curtain at the separation edge. At least one rinsing device is used to apply a flowing gaseous rinsing medium to the at least one separation edge, and at least one blocking device is suitable for keeping air movements of the ambient air away from the curtain. A method for coating a moving material web is also provided.

A curtain application unit for applying a liquid or pasty application medium to at least one surface of a moving material web, in particular a fibrous web, includes an application head having at least one separation edge extending substantially over the width of the application head. The application medium exits the application head in the form of a free-falling curtain at the separation edge. At least one rinsing device is used to apply a flowing gaseous rinsing medium to the at least one separation edge, and at least one blocking device is suitable for keeping air movements of the ambient air away from the curtain. A method for coating a moving material web is also provided.

There is provided a method of producing a sheet comprising fibrillated cellulose, comprising the steps of: a) providing chemically modified cellulose fibres in which a chargeable moiety has been introduced and the C.sub.2-C.sub.3 bond has been broken in at least part of the D-glucose units, wherein the charge density measured according to SCAN-CM 65:02 is 150-1500 μeq/g; b) forming a fibre web by dewatering a slurry comprising the modified cellulose fibres; and c) adding a base to the fibre web so as to obtain the sheet comprising fibrillated cellulose.

There is provided a method of producing a sheet comprising fibrillated cellulose, comprising the steps of: a) providing chemically modified cellulose fibres in which a chargeable moiety has been introduced and the C.sub.2-C.sub.3 bond has been broken in at least part of the D-glucose units, wherein the charge density measured according to SCAN-CM 65:02 is 150-1500 μeq/g; b) forming a fibre web by dewatering a slurry comprising the modified cellulose fibres; and c) adding a base to the fibre web so as to obtain the sheet comprising fibrillated cellulose.

The present invention relates to a method for production of product comprising a first ply, the method comprising the steps of: providing a fibrous suspension comprising fibers; providing said fibrous suspension to a porous medium to form a substrate comprising fibers; providing a first additive suspension comprising a first strengthening agent, wherein the first strengthening agent is microfibrillated cellulose; providing a second additive suspension comprising at least one retention agent and/or at least one drainage agent; dewatering said substrate on said porous medium; performing additive addition to said substrate during said dewatering of said substrate on said porous medium, wherein the additive addition is performed when the substrate has a dry content of less than 20 weight-%, preferably less than 10 weight-%, most preferably less than 7 weight-%, and wherein the additive addition comprises adding at least a layer of said first additive suspension and a layer of said second additive suspension to said substrate by means of multilayer curtain coating, and further dewatering and drying said substrate after said dewatering on said porous medium so as to provide said first ply. The invention also relates to a paper, board or non-woven product obtainable by the method.

The present invention relates to a method for production of product comprising a first ply, the method comprising the steps of: providing a fibrous suspension comprising fibers; providing said fibrous suspension to a porous medium to form a substrate comprising fibers; providing a first additive suspension comprising a first strengthening agent, wherein the first strengthening agent is microfibrillated cellulose; providing a second additive suspension comprising at least one retention agent and/or at least one drainage agent; dewatering said substrate on said porous medium; performing additive addition to said substrate during said dewatering of said substrate on said porous medium, wherein the additive addition is performed when the substrate has a dry content of less than 20 weight-%, preferably less than 10 weight-%, most preferably less than 7 weight-%, and wherein the additive addition comprises adding at least a layer of said first additive suspension and a layer of said second additive suspension to said substrate by means of multilayer curtain coating, and further dewatering and drying said substrate after said dewatering on said porous medium so as to provide said first ply. The invention also relates to a paper, board or non-woven product obtainable by the method.

A curtain applicator for applying a liquid or pasty application medium to at least one surface of a running material web, in particular a fibrous web. The curtain applicator has an applicator nozzle, in particular a slotted nozzle, which under the effect of gravity, and optionally with further forces, is suitable for dispensing a single-tier or multi-tier curtain onto the surface of the material web. The curtain applicator further has a wiping device which is suitable for keeping entrained air carried by the material web away from the curtain. Moreover, there is provided at least one further blocking device which is suitable for keeping air movements of the ambient air away from the curtain.

A curtain applicator for applying a liquid or pasty application medium to at least one surface of a running material web, in particular a fibrous web. The curtain applicator has an applicator nozzle, in particular a slotted nozzle, which under the effect of gravity, and optionally with further forces, is suitable for dispensing a single-tier or multi-tier curtain onto the surface of the material web. The curtain applicator further has a wiping device which is suitable for keeping entrained air carried by the material web away from the curtain. Moreover, there is provided at least one further blocking device which is suitable for keeping air movements of the ambient air away from the curtain.

A method for manufacturing a paper barrier base material includes a step of applying a water vapor barrier layer coating liquid that contains at least a water vapor barrier resin and a pigment onto a paper base material by a curtain coating method to form a water vapor barrier layer. The water vapor barrier layer coating liquid has a spinnability of 0.07 seconds or more and 0.4 seconds or less at a solid content concentration of 32% by weight and a temperature of 25° C. The method is intended to achieve good stability of a coating liquid and good continuous operability.

A method for manufacturing a paper barrier base material includes a step of applying a water vapor barrier layer coating liquid that contains at least a water vapor barrier resin and a pigment onto a paper base material by a curtain coating method to form a water vapor barrier layer. The water vapor barrier layer coating liquid has a spinnability of 0.07 seconds or more and 0.4 seconds or less at a solid content concentration of 32% by weight and a temperature of 25° C. The method is intended to achieve good stability of a coating liquid and good continuous operability.