To provide a new inorganic particle composite fiber including a large amount of adhering inorganic particles, An inorganic particle composite fiber includes: fiber; and inorganic particles fixed to the fiber, the fiber being thread-like in shape, the inorganic particles being fixed to the fiber via an ionic polymer.

To provide a new inorganic particle composite fiber including a large amount of adhering inorganic particles, An inorganic particle composite fiber includes: fiber; and inorganic particles fixed to the fiber, the fiber being thread-like in shape, the inorganic particles being fixed to the fiber via an ionic polymer.

N-vinyllactam-containing polyvinylamine-based polymers, methods for producing N-vinyllactam-containing polyvinylamine-based polymers, and methods for papermaking are provided. An exemplary method for producing an N-vinyllactam-containing polyvinylamine-based polymer includes performing radical polymerization of a vinylamide monomer, a vinyl monomer containing an amide functional group, and, optionally, a vinyl monomer that contains a carboxylic acid group, to obtain a prepolymer. Further, the method includes hydrolyzing the prepolymer under alkaline conditions to obtain the N-vinyllactam-containing polyvinylamine-based polymer.

A method for manufacture of paper or board, in which method an inverted solution of cationic polymer is added to the fiber suspension for providing retention enhancement without over-flocculating fiber stock and destruction sheet formation and/or improving drainage and enhancing or at least maintaining strength of paper or board, An inverted solution has a bulk viscosity of 50-150 mPas at 0.2 weight-% cationic polymer concentration and inverted solution comprises cationic polymer obtained by reverse phase emulsion polymerization of a monomer blend comprising non-ionic monomers, 15-50 mol-% cationic monomers, an optionally at most 50 ppm of a crosslinking agent, and a chain transfer agent, and the obtained reverse phase emulsion of cationic polymer is inverted into an aqueous solution.

A method for manufacture of paper or board, in which method an inverted solution of cationic polymer is added to the fiber suspension for providing retention enhancement without over-flocculating fiber stock and destruction sheet formation and/or improving drainage and enhancing or at least maintaining strength of paper or board, An inverted solution has a bulk viscosity of 50-150 mPas at 0.2 weight-% cationic polymer concentration and inverted solution comprises cationic polymer obtained by reverse phase emulsion polymerization of a monomer blend comprising non-ionic monomers, 15-50 mol-% cationic monomers, an optionally at most 50 ppm of a crosslinking agent, and a chain transfer agent, and the obtained reverse phase emulsion of cationic polymer is inverted into an aqueous solution.

A method for manufacturing a fibrous web, such as web of paper, board, tissue or the like is disclosed. The method includes obtaining at least one fibre suspension of lignocellulosic and/or cellulosic fibres and feeding the fibre suspension into an intermediate residence entity. The fibre suspension including bacterial endospores, is discharged out of the intermediate residence entity via an outlet after a residence time of at least 2 hours in the intermediate residence entity and after a time delay the fibre suspension is formed into a fibrous web. Bacterial endospores are sensitized by adding a germinant surfactant including a primary or secondary ammonium head group and a linear unsubstituted C12-alkyl tail, to the fibre suspension at an addition point located at a lower part of the intermediate residence entity or after the outlet of the intermediate residence entity, but before the formation of the fibrous web.

Multi-ply paper products and methods for manufacturing such products are provided. A method includes producing a foam of water, air, a foaming agent, uncooked starch, and a dry strength agent; applying the foam to a first surface of a base embryonic ply web; providing an applied embryonic ply web having a first surface and contacting the first surface of the base web with the first surface of the applied web at an interface to form a combined ply web; and selectively applying vacuum pressure to a second surface of the base web to retain particles of the uncooked starch on or near the first surface, to draw molecules of the dry strength agent into the base web and/or to the first surface of the applied web to retain particles of the uncooked starch in the interface and to draw molecules of the dry strength agent into the applied web.

Multi-ply paper products and methods for manufacturing such products are provided. A method includes producing a foam of water, air, a foaming agent, uncooked starch, and a dry strength agent; applying the foam to a first surface of a base embryonic ply web; providing an applied embryonic ply web having a first surface and contacting the first surface of the base web with the first surface of the applied web at an interface to form a combined ply web; and selectively applying vacuum pressure to a second surface of the base web to retain particles of the uncooked starch on or near the first surface, to draw molecules of the dry strength agent into the base web and/or to the first surface of the applied web to retain particles of the uncooked starch in the interface and to draw molecules of the dry strength agent into the applied web.

The present invention concerns a process for preparing self-binding pigment particles from an aqueous suspension of calcium carbonate containing material, wherein an anionic binder and at least one cationic polymer are mixed with the suspension.

The present invention concerns a process for preparing self-binding pigment particles from an aqueous suspension of calcium carbonate containing material, wherein an anionic binder and at least one cationic polymer are mixed with the suspension.