Abstract:
The invention relates to a process for manufacturing liquid packaging board, in which process a board pulp is treated with a percarboxylic acid by adding to the pulp percarboxylic acid in an amount of 0.5-5 kg/ton of dry pulp, indicated as a 100 percent percarboxylic acid, whereafter, or simultaneously with the percarboxylic acid treatment, sizing is carried out with a combination of a resin size and a neutral size, which is followed by board forming. The manufactured board has good resistance to liquid penetration.
Abstract:
The invention relates to a stabilizing composition comprising following components (A) a polymer having the following formula: wherein R1 is a hydrogen atom or an alkyl group containing 1 to 12 carbon atoms, R2 is —COOM or —CH2COOM, M is a hydrogen atom, an alkali metal ion, an alkaline earth metal ion, an ammonium ion or a mixture thereof, n, m and k are molar ratios of corresponding monomers, wherein n is 0 to 0.95, m is 0.05 to 0.9, and k is 0 to 0.8, and (n+m+k) equals 1, and the weight average molecular weight is between 500 and 20,000,000 g/mol, (B) a chelating agent, (C) a poly-alpha-hydroxyacrylic acid or an alkaline salt thereof or the corresponding polylactone thereof, and (D) optionally a polycarboxylic acid polymer or an alkaline salt thereof. The invention also relates to a process for the treatment of a fiber material.
Abstract:
The present invention relates to a polymer composition for peroxide bleaching of a cellulosic fiber material, said composition being in the form of a stable aqueous polymer solution obtained by bringing in an aqueous medium a first polymer (A) comprising a partly or totally acidic homopolymer of acrylic acid, methacrylic acid or maleic acid, or a copolymer of acrylic acid and/or methacrylic acid with an unsaturated dicarboxylic acid, into contact with a second polymer (B) comprising a polylactone of a poly-alfa-hydroxyacrylic acid in solid form or as a moist powder or as a slurry, said polymer solution having a pH of at most 5. The invention also relates to peroxide bleaching processes.
Abstract:
The present invention relates to a stabilizing composition comprising following components (A) a polymer having following formula wherein R1 is a hydrogen atom or an alkyl group containing 1 to 12 carbon atoms, R2 is —COOM or —CH2COOM, M is a hydrogen atom, an alkali metal ion, an alkaline earth metal ion, an ammonium ion or a mixture thereof, n, m and k are molar ratios of corresponding monomers, wherein n is 0 to 0.95, m is 0.05 to 0.9, and k is 0 to 0.8, and (n+m+k) equals 1, and the weight average molecular weight is between 500 and 20,000,000 g/mol, (B) a chelating agent, and (C) an alkaline earth metal compound. The invention also relates to a process for the treatment of a fiber material.
Abstract:
The invention relates to a process for the bleaching of chemical pulp, wherein the pulp is delignified and/or bleached with chlorine dioxide or with a combination of chlorine dioxide and a per-compound, and additionally the pulp is chelated in order to bind heavy metals, such as Fe, Mn and/or Cu, to a chelate complex. The chelate complex is selected from the group made up of N-bis-[(1,2-dicarboxylethoxy)-ethyl]-amine, N-bis[(1,2-dicarboxylethoxy)-ethyl]-aspartic acid and N-tris-[(1,2-dicarboxylethoxy)-ethyl]-amine, and the alkali metal and earth-alkali metal salts of these, and the chelating treatments are carried out simultaneously by combining the chelating chemical with the pulp in the same bleaching stage as chlorine dioxide.
Abstract:
The invention relates to a process for the treatment of a fibre material comprising the step of contacting the fibre material in an aqueous medium with a chelating agent and a polymer having following general formula wherein R1 is a hydrogen atom or an alkyl group containing 1 to 12 carbon atoms, R2 is —COOM or —CH2COOM, M is a hydrogen atom, an alkali metal ion, an alkaline earth metal ion, an ammonium ion or a mixture thereof, n, m and k are molar ratios of corresponding monomers, wherein n is 0 to 0.95, m is 0.05 to 0.9, and k is 0 to 0.8, and (n+m+k) equals 1, and the weight average molecular weight is between 500 and 20,000,000 g/mol. The invention also relates to a composition comprising a chelating agent and the above polymer.
Abstract:
The present invention relates to a polymer composition for peroxide bleaching of a cellulosic fibre material, said composition being in the form of a stable aqueous polymer solution obtained by bringing in an aqueous medium a first polymer (A) comprising a partly or totally acidic homopolymer of acrylic acid, methacrylic acid or maleic acid, or a copolymer of acrylic acid and/or methacrylic acid with an unsaturated dicarboxylic acid, into contact with a second polymer (B) comprising a polylactone of a poly-alfa-hydroxyacrylic acid in solid form or as a moist powder or as a slurry, said polymer solution having a pH of at most 5. The invention also relates to peroxide bleaching processes.
Abstract:
The present invention relates to a polymer composition for peroxide bleaching of a cellulosic fiber material, said composition being in the form of a stable aqueous polymer solution obtained by bringing in an aqueous medium a first polymer (A) comprising a partly or totally acidic homopolymer of acrylic acid, methacrylic acid or maleic acid, or a copolymer of acrylic acid and/or methacrylic acid with an unsaturated dicarboxylic acid, into contact with a second polymer (B) comprising a polylactone of a poly-alfa-hydroxyacrylic acid in solid form or as a moist powder or as a slurry, said polymer solution having a pH of at most 8, The invention also relates to peroxide bleaching processes.