The invention relates to transfer paper for sublimation printing, comprising a fibrous substrate, said transfer paper having one or more cationic agents on at least one face thereof, deposited on the fibrous substrate by means of surface treatment, the amount of cationic agent(s) being greater than or equal to 8% by dry weight of the total dry weight of the compound(s) added to the fibrous substrate by means of the surface treatment.

A composition for increasing paper strength includes a dialdehyde-modified polyacrylamide strengthening agent, a water soluble compound that is soluble at about 5 wt % or greater in water at about 25 C., and water. The water soluble compound is typically present in a weight amount that is greater than a weight amount of the strengthening agent. The composition is formed by combining the strengthening agent and the water soluble compound in aqueous media to form the composition, wherein on a dry basis the water soluble compound is typically present in a greater amount than the strengthening agent, drying the composition to form a powder or paste that has a water content of less than about 10 weight percent and is stable after storage at about room temperature for about six months, and reconstituting the powder or paste by adding water thereto. The reconstituted composition may then be used to make paper.

A method for the production of paper or cardboard is provide comprising the following steps: (A) Adding a water soluble polymer P to a first aqueous pulp suspension, wherein polymer P is obtainable by Polymerizing to a polymer V of (i) 33 to 83 mol % of a monomer of formula I

##STR00001## in which R.sup.1H or C.sub.1-C.sub.6 alkyl, (ii) 6 to 56 mol % of diallyl dimethyl ammonium chloride, diallyl diethyl ammonium chloride or a salt form of a monoethylenically unsaturated monomer, (iii) 11 to 61 mol % of a monoethylenically unsaturated carboxylic acid, sulfonic acid or phosphonic acid, or salt forms thereof, (iv) 0 to 50 mol % of one or more ethylenically unsaturated monomers, and hydrolyzing the NC(O)R.sup.1 groups to form primary amino or amidine groups, (B) dehydrating the second aqueous pulp suspension to a wet paper structure, (C) dehydrating the wet paper structure.

Quaternary ammonium compound compositions and more particularly quaternary ammonium compound compositions including greater than 25% by weight of a quaternary ammonium compound, methods for making same, fibrous structures employing same, and methods for treating fibrous structures with same are provided.

A process for flocculating filler particles in water is provided. The process comprises adding a flocculant to a mixture comprising filler particles and water, wherein the flocculant has a reduced specific viscosity (RSV) of from about 5 dL/g to about 16 dL/g, a viscosity average molecular weight of from about 1,200,000 to about 7,500,000, and a cationic charge of from about 5 mol % to about 50 mol %. Flocs formed by flocculation of the filler particles and the flocculant have a median particle size of from about 10 m to about 150 m. The filler is not precipitated calcium carbonate alone. The flocs provided by the process are useful in increasing ash content of a paper product.

The present invention relates to a process for manufacturing a sheet of paper and/or board from a fibrous suspension, according to which, before the formation of said sheet, added to the fibrous suspension, at one or more injection points, are at least two retention aids respectively: (a) at least one water-soluble organic cationic polymer P1 having a cationicity greater than 2 meq.Math.g.sup.1, and (b) at least one water-soluble amphoteric polymer P2 of at least one anionic monomer and of at least one cationic monomer. The polymer P2 is added to the fibrous suspension after dissolving, in aqueous solution, the polymer P2 previously obtained by one of the following polymerization techniques: gel polymerization, suspension polymerization, inverse emulsion polymerization, dispersion polymerization. The polymer P2 has a factor F>2, said factor F being defined by the formula: F=UL.sup.2[(100A)/(100C)] with UL: Brookfield viscosity of the polymer P2 at 0.1% by weight in a 1M aqueous solution of NaCl, at 23 C., with a UL module and at 60 rev.Math.min.sup.1, A and C corresponding respectively to the molar percentages of the anionic and cationic monomers of the polymer P2.

Method of papermaking comprises: treating filler with a starch and a flocculant to form a filler floc; combining the filler floc with the cellulose fiber stock; and forming a paper mat from the combination of filler floc and cellulose fiber stock. The method have been found to result in larger particle sizes for the filler flocs, improved shear stability, and improved sheet strength in the paper mat.

A cationic polyether amine dispersant for papermaking fibers comprises the polymeric reaction product of a polyether diamine, a polyether bisepoxide and a quaternary ammonium salt. The polyether diamine, the polyether bisepoxide and the quaternary ammonium salt reactants are reacted in the following molar ratios: the molar ratio of amine functionality of the polyether diamine to epoxide functionality of the polyether bisepoxide is from 0.5:1 to 2:1 and the molar ratio of the amine functionality of the polyether diamine to the epoxide functionality of the quaternary ammonium salt is from 10:1 to 40:1. The dispersant is used in stock preparation used in paper products including absorbent products as well as paperboard.

The invention relates to a method for treating starch in pulp, paper and board making processes, in which processes recycled fibre material is used as raw material wherein the recycled fibre material is pulped in a pulper and obtaining a pulp flow comprising an aqueous phase and at least recycled fibres and starch dispersed in the aqueous phase. The method comprising the following steps: adding amylase enzyme inhibitor and/or at least one biocide to pulp flow or to an aqueous process flow comprising starch for preventing starch degradation, andadding an amphoteric polymer obtained by copolymerisation of (meth)acrylamide with cationic and anionic monomers to pulp flow or to an aqueous process flow comprising starch for binding starch to the fibres.

A method is disclosed for dewatering of sludge from a pulp, paper or board making process, such as deinking sludge, including obtaining of an aqueous sludge including an aqueous phase and a fibre material suspended in the aqueous phase. The sludge is subjected to a pre-thickening step, where a first part of the aqueous phase is removed from the sludge and to a pressing step, where a second part of the aqueous phase is removed from the sludge, thereby obtaining a dry pressed sludge. Before or at the pre-thickening step a polymer composition having a charge density of at the most 1.7 meq/g, preferably at most 1.5 meq/g, more preferably at most 1.1 meq/g, is added to the sludge.