Kemira Oyj

Other

Anneli Lepo

Tarja Turkki

Elsi Turunen

Helena Peuranen

Matti Hietaniemi

Asko Karppi

Marco Polverari

Kimmo Strengell

Mari Ojanen

Erland Hermansson

Sami Puttonen

Jussi Nikkarinen

Michael P O'Toole

Bernhard Überbacher

Paula Hirsilä

Ville Nyman

Michael O'toole

Taru Jokinen

Yingying Liu

Anna Stankevich

Bernhard Uberbacher

Bernhard ÜBerbacher

The invention relates to a surface size composition for surface sizing of paper, board, or the like. The composition comprises at least an aluminium compound and an anionic lignin-carbohydrate complex.

Surface size composition and its use

The invention relates to the use of a surface size composition comprising at least one cellulose derivative selected from cellulose ethers, excluding carboxyalkyl celluloses, for providing compression strength for a fibrous web, such as paper, board or the like, preferably comprising recycled cellulosic fibres. The invention relates also to a method for surface sizing of paper, board or the like.

Use of a cellulose derivative and method for surface sizing

A coating structure for a sheet-like substrate is disclosed including cellulosic fibres and a sheet-like product. The structure includes at least one pre-coat layer and a top coat layer, where the pre-coat layer(s) and the top coat layer include 10-90 weight-% of a styrene (meth)acrylate copolymer which is polymerised in the presence of a stabiliser, and which has a glass transition temperature Tg≤20° C., preferably ≤15° C., more preferably ≤13° C. Furthermore, the pre-coat layer(s) includes a polysaccharide, such as starch, and the top coat layer includes 5-60 weight-% of at least one water-soluble coating binder, which is selected from polysaccharides and polyvinyl alcohols, as well as at most 5.0 weight-% of a cross-linker, which reacts with —OH or —COOH groups.

Coating structure, sheet-like product and its use

A method of producing a surface sizing composition, the method comprising: providing a metal salt having at least 3 valence electrons, wherein the metal salt is selected from the group of aluminium sulfate, aluminium chloride, aluminium nitrate, polyaluminium sulfate (PAS), polyaluminium chloride (PAC), and polyaluminium chloride sulfate (PACS), polyaluminium formiate, polyaluminium nitrate, and any combination thereof; providing an aqueous polymer dispersion, wherein the aqueous polymer dispersion is an aqueous polymer dispersion (A) and an aqueous prepolymer composition (B), wherein the aqueous polymer dispersion (A) is obtainable by free radical emulsion copolymerizing a first ethylenically unsaturated monomer blend, and wherein the aqueous prepolymer composition (B) is obtainable by free radical emulsion copolymerizing in a polymerization solvent comprising C1-6-carboxylic acid and C1-6-carboxylic acid anhydride, a second ethylenically unsaturated monomer blend; and mixing the metal salt and the aqueous polymer dispersion to provide a surface sizing composition to be used in papermaking.

Surface sizing composition, method of production, and use thereof

A coating structure for a sheet-like substrate, which includes lignocellulosic fibres is disclosed. The structure includes at least one pre-coat layer including at least 70 weight-% of a first styrene (meth)acrylate copolymer polymerised in the presence of a stabiliser, having a glass transition temperature Tg &#x2264;20&#xb0; C. preferably &#x2264;10&#xb0; C., &#x2264;30 weight-% of inorganic platy mineral particles and 0.01-2 weight-% of at least one first thickener. The coating structure further includes a top coat layer including at least 50 weight-% of a second styrene (meth)acrylate copolymer polymerised in the presence of a stabiliser having a glass transition temperature Tg &#x2264;20&#xb0; C. preferably &#x2264;10&#xb0; C., &#x2264;30 weight-% of inorganic mineral particles, 0.01-5 weight-% of at least one second thickener and 0.5-30 weight-% of an antiblocking agent. Further disclosed is a sheet-like product coated with the coating structure.

The present invention relates to a surface sizing composition comprising a metal salt, wherein the metal has at least 3 valence electrons, and an aqueous polymer dispersion, wherein the aqueous polymer dispersion is an aqueous polymer dispersion (A) obtainable by free radical emulsion copolymerizing a first ethylenically unsaturated monomer blend comprising (a) 0 to 75% by weight of at least one optionally substituted styrene, (b) 15 to 100% by weight of at least one C1-C4-alkyl (meth)acrylate, and (c) 0 to 10% by weight of other ethylenically unsaturated copolymerizable monomers, wherein the sum (a)+(b)+(c) is 100%, in the presence of a water-soluble redox system comprising a first free radical initiator for the free radical emulsion copolymerization and an aqueous prepolymer composition (B) obtainable by free radical emulsion copolymerizing in a polymerization solvent comprising C1-6-carboxylic acid and C1-6-carboxylic acid anhydride, a second ethylenically unsaturated monomer blend comprising (i) 5 to 50% by weight of at least one ethylenically unsaturated quaternary amine selected from quaternary salt of N,N,N-tri(C1-4-alkyl)amino C1-4-alkyl(meth)acrylate with a mineral acid or an organic acid and/or quaternary salt of N,N,N-tri(C1-4-alkyl)amino C1-4-alkyl(meth)acrylamide with a mineral acid or an organic acid, (ii) 0 to 40%, preferably 0%, by weight of at least one ethylenically unsaturated tertiary amine selected from N,N-di(C1-4-alkyl)amino C1-4-alkyl(meth)acrylate and/or N,N-di(C1-4-alkyl)amino C1-4-alkyl(meth)acrylamide, (iii) 10 to 95% by weight of at least one optionally substituted styrene, (iv) 0 to 50% by weight of at least one C1-C4-alkyl (meth)acrylate, and (v) 0 to 10% by weight of other ethylenically unsaturated copolymerizable monomers, wherein the sum (i)+(ii)+(iii)+(iv)+(v) is 100%, in the presence of a second free radical initiator, and adding water to the obtained polymer dispersion to obtain the aqueous prepolymer composition. The present invention further relates to production thereof and use on cellulosic materials.

The invention relates to a composition for modifying rheology of coating colour and its use. The composition comprises an aqueous polymer dispersion, comprising a copolymer of monomer (a), which is at least one optionally substituted styrene, and monomer (b), which is at least one C1-C4-alkyl (meth)acrylate. The copolymer has a particle size D50&#x3c;100 nm. Composition comprises also degraded starch having an average molecular weight Mn&#x3c;1000 g/mol.

Composition for modifying rheology of coating color, its use and a coating color

Provided herein is an aqueous polymer dispersion (A) obtainable by free radical emulsion copolymerizing a first ethylenically unsaturated monomer blend having 15 to 100% by weight of at least one C1-C4-alkyl (meth)acrylate, in the presence of a water-soluble redox system having a first free radical initiator for free radical emulsion copolymerization and an aqueous prepolymer composition (B) obtainable by free radical emulsion copolymerizing in a polymerization solvent having C1-6-carboxylic acid and C1-6-carboxylic acid anhydride a second ethylenically unsaturated monomer blend with 5 to 50% by weight of at least one ethylenically unsaturated quaternary amine, and 10 to 95% by weight of at least one optionally substituted styrene, in the presence of a second free radical initiator.

Cationic surface sizing agent

The present invention relates to a sizing agent composition comprising starch, lignosulfonate and poly(alkyl acrylate), poly(alkyl (meth)acrylate), a mixture of poly(alkyl acrylate) and poly(alkyl methacrylate) or a copolymer of alkyl acrylate and alkyl (meth)acrylate. The present invention further relates to a method for preparing the sizing agent composition, and use of the sizing agent composition for sizing paper, paper products or board.

Method for producing a sizing agent composition, a sizing agent composition and use thereof

The invention relates to an aqueous polymer dispersion having a viscosity of &#x2264;150 m Pas at 40% solids content and comprising polymer particles having a particle size D50 less than 85 nm. The polymer dispersion is obtainable by free radical emulsion copolymerisation of at least monomer (a) and monomer (b), where monomer (a) is at least one optionally substituted styrene and monomer (b) is at least one C1-C4-alkyl (meth)acrylate, in a reaction mixture comprising degraded starch which has an average molecular weight Mn&#x3c;1000 g/mol. The invention relates also to the use of the polymer dispersion and method for preparing it.

Aqueous polymer dispersion, its use and method for preparing aqueous polymer dispersion

The present invention provides a core/shell polymer particle for surface sizing of cellulosic products, wherein the core polymer and the shell polymer of the core/shell polymer particle are polymerized from monomers comprising at least 40%, by weight of monomers selected from branched C3-10-alkyl (meth)acrylate, styrene, linear C1-10-alkyl (meth)acrylate, and acrylonitrile, based on the total weight of the monomers of the core/shell polymer particle; provided that the polymer of the core/shell polymer particle comprises at least 40% by weight of branched C3-6-alkyl (meth)acrylate and at least 50% by combined weight of branched C3-10-alkyl (meth)acrylate and styrene, linear C1-10-alkyl (meth)acrylate, and/or acrylonitrile, based on the total weight of the monomers of the core/shell polymer particle.

Core/shell polymer particles as surface sizing agents

The invention relates to a water-soluble polymer product in particle form, comprising amphoteric polyacrylamide, which is obtained by gel polymerisation of acrylamide together with anionic and cationic monomers. The amphoteric polyacrylamide has a mass average molecular weight MW of 1 500 000-6 000 000 g/mol, and a total ionicity of 4-15 mol-%, whereby the polymer product has a polymer content of at least 60 weight-%. The invention relates also to uses of the polymer product in paper and board making.

Polymer product in particle form and its use

A composition includes a dispersion, having an aqueous phase containing a dissolved water soluble cationic coagulant polymer and if needed a dissolved inorganic salt. The aqueous phase further contains a dispersed water soluble flocculant polymer, wherein the water soluble flocculant polymer is formed of a water soluble ethylenically unsaturated monomer or monomer blend which are polymerized in the aqueous phase. The water soluble cationic coagulant polymer is cationic poly(alkyleneamine), which is the reaction product of the following reaction:HN&#x2014;(CH)&#x2014;NR&#x2014;(CH)&#x2014;NH+Cl&#x2014;CHCH&#x2014;Cl,

Growing community of inventors

Tampere, Finland

Anneli Lepo