The present disclosure provides for a paper product. The paper product has: (a) from about 20% to about 90% by weight of the dry fiber basis of the paper product of a refined soft wood pulp fiber mixture, (b) pulp fibers selected from the group consisting of hard wood fibers, non-wood fibers, recycled fibers, synthetic polymer fibers, bleached eucalyptus kraft fibers, and combinations thereof; and, (c) not more than about 10% by weight moisture.

A differential density paper product comprising at least one paper web is disclosed. The paper product has: (a) from about 20% to about 90% by weight of the dry fiber basis of the paper product of a refined soft wood pulp fiber mixture, (b) pulp fibers selected from the group consisting of hard wood fibers, non-wood fibers, recycled fibers, synthetic polymer fibers, bleached eucalyptus kraft fibers, and combinations thereof; and, (c) not more than about 10% by weight moisture.

A differential density paper product comprising at least one paper web is disclosed. The paper product has: (a) from about 20% to about 90% by weight of the dry fiber basis of the paper product of a refined soft wood pulp fiber mixture, (b) pulp fibers selected from the group consisting of hard wood fibers, non-wood fibers, recycled fibers, synthetic polymer fibers, bleached eucalyptus kraft fibers, and combinations thereof; and, (c) not more than about 10% by weight moisture.

A polymer composition includes a first host polymer, which is a copolymer of (meth)acrylamide and at least one cationic first monomer, and a second polymer, which is a copolymer of (meth)acrylamide and at least one cationic second monomer. The second polymer is polymerised in presence of the first host polymer, and the first host polymer has a higher cationicity than the second polymer, the difference in cationicity of the first host polymer and the second polymer being at least 3 mol-%, at least 5 mol-%, more preferably at least 7 mol-%. The polymer composition has a standard viscosity of >2.0 mPas, measured at 0.1 weight-% solids content in an aqueous NaCl solution (1 M), at 25 C., using Brookfield VII T viscometer with UL adapter. The invention relates also to uses of said polymer composition.

A polymer composition includes a first host polymer, which is a copolymer of (meth)acrylamide and at least one cationic first monomer, and a second polymer, which is a copolymer of (meth)acrylamide and at least one cationic second monomer. The second polymer is polymerised in presence of the first host polymer, and the first host polymer has a higher cationicity than the second polymer, the difference in cationicity of the first host polymer and the second polymer being at least 3 mol-%, at least 5 mol-%, more preferably at least 7 mol-%. The polymer composition has a standard viscosity of >2.0 mPas, measured at 0.1 weight-% solids content in an aqueous NaCl solution (1 M), at 25 C., using Brookfield VII T viscometer with UL adapter. The invention relates also to uses of said polymer composition.

The invention relates to a method and treatment system for making of paper or surface ply of a multi-ply board from a fibre suspension, where at least 90 weight-% of fibres originate from chemical pulping process, chemi-thereto mechanical pulping process and/or office waste deinking pulping process. The fibre suspension further comprises inorganic mineral particles and cationic starch. A cationic copolymer of acrylamide and cationic monomers is incorporated to the fibre suspension and it is allowed to interact by flocculation with at least some of the said components of the fibre suspension. An anionic copolymer of acrylamide and more than 30 mol-% of anionic monomers is added to the fibre suspension, and fibre suspension is formed into a fibre web and drying the web to a dryness of at least 80%. An aqueous surface composition comprising polymeric binder is applied on the surface of the web.

The invention relates to a method and treatment system for making of paper or surface ply of a multi-ply board from a fibre suspension, where at least 90 weight-% of fibres originate from chemical pulping process, chemi-thereto mechanical pulping process and/or office waste deinking pulping process. The fibre suspension further comprises inorganic mineral particles and cationic starch. A cationic copolymer of acrylamide and cationic monomers is incorporated to the fibre suspension and it is allowed to interact by flocculation with at least some of the said components of the fibre suspension. An anionic copolymer of acrylamide and more than 30 mol-% of anionic monomers is added to the fibre suspension, and fibre suspension is formed into a fibre web and drying the web to a dryness of at least 80%. An aqueous surface composition comprising polymeric binder is applied on the surface of the web.

Drainage and press dewatering system for manufacture of paper, board or the like, comprising (a) amphoteric polyacrylamide, which is a copolymer obtained by polymerizing (meth)acrylamide and 1-80 mol-% of cationic monomers and/or 0.1-70 mol-% of anionic monomers, the polyacrylamide having an intrinsic viscosity in the range of 6-38 dl/g, (b) inorganic microparticles of siliceous material, such as colloidal silica or bentonite, and (c) a high-charged cationic coagulant having a charge density over 5 meq/g and preferably over 6 meq/g determined at pH 6 and selected from aluminium based coagulants, organic polymers and mixtures thereof.

Drainage and press dewatering system for manufacture of paper, board or the like, comprising (a) amphoteric polyacrylamide, which is a copolymer obtained by polymerizing (meth)acrylamide and 1-80 mol-% of cationic monomers and/or 0.1-70 mol-% of anionic monomers, the polyacrylamide having an intrinsic viscosity in the range of 6-38 dl/g, (b) inorganic microparticles of siliceous material, such as colloidal silica or bentonite, and (c) a high-charged cationic coagulant having a charge density over 5 meq/g and preferably over 6 meq/g determined at pH 6 and selected from aluminium based coagulants, organic polymers and mixtures thereof.

The present disclosure relates to a dry strength agent composition, use of an amine-containing cationic polymer for enhancing the dry strength of paper, and a method for enhancing the dry strength of paper. The dry strength agent composition includes at least two components. The first component is an amine-containing cationic polymer and the second component may be one or more anionic or amphoteric polymers.