Abstract: Coated paper product and method and apparatus for the production thereof. The paper product comprises a base paper, the porosity of which is at least 300 ml/min (Bentsen) and at least one side of which is coated with a pigment-bearing coating layer. The coating layer according to the present invention comprises a homogeneous film, which is formed of binder and pigments and which is brought onto the surface of the base paper using curtain coating so that the variation of the grammage of the layer is less than 5%, and so that the coating layer is not penetrated into the base paper, in which case the coating layer covers at least 95% of the surface of the base paper. By means of the present invention such a good coverage is achieved that the porosity of the base paper does not affect the gloss or smoothness of the coated paper, nor how the paper functions as a printing base.

Abstract: The invention relates to the use of precipitated calcium carbonates (PCC) as fillers for the manufacture of base paper together with mechanical hardwood pulp and chemical softwood pulp, and to a method for the manufacture of base paper, in which method pulp produced from hard woods, in particular from the wood of the genus Populus, and chemical softwood pulp are used together with a PCC filler. The use of precipitated calcium carbonate (PCC) for the manufacture of base paper together with mechanical hardwood pulp and chemical softwood pulp is characterized in that ≧20 wt-% of the fibres of the mechanical hardwood pulp is included in the fibre size fraction of <200 mesh and 10-40 wt-% of them is included in the fibre size fraction of {fraction (28/48)} mesh, the brightness of the mechanical hardwood pulp is ≧75, the particle size distribution of the precipitated calcium carbonate is 90%≦9 &mgr;m, 50%≦5 &mgr;m and 20%≦1.5 &mgr;m, and the basis weight of the base paper is 25-150 g/m2.

Abstract: The present invention relates to a method for coating of a fibrous web. According to the method a coating color with pigments is applied to the surface of the web and dried in order to form a coated web. The invention comprises using a coating color which contains pigments having a steep particle size distribution, a maximum of 35% of the pigment particles being smaller than 0.5 &mgr;m. The coating color is spread on the surface of the web with a coating speed of at least 1450 m/min, preferably over 1600 m/min. The coating pigment having a steep particle size distribution gives rise to a coating color which solidifies at much lower dry substance than conventional coating colors. In this way coating can be controlled at high speed without runnability and quality problems.

Abstract: The present invention relates to a method for coating of a fibrous web. According to the method a coating color with pigments is applied to the surface of the web and dried in order to form a coated web. The invention comprises using a coating color which contains pigments having a steep particle size distribution, a maximum of 35% of the pigment particles being smaller than 0.5 &mgr;m. The coating color is spread on the surface of the web with a coating speed of at least 1450 m/min, preferably over 1600 m/min. The coating pigment having a steep particle size distribution gives rise to a coating color which solidifies at much lower dry substance than conventional coating colors. In this way coating can be controlled at high speed without runnability and quality problems.

Abstract: The present invention concerns a process for preparing a paper web. According to the process a pulp is formed from a fibrous raw material, a web is formed from the pulp and it is dried on a paper machine. According to the invention the pulp is formed from a mechanical pulp produced from a peroxide bleached mechanical wood raw material of the genus Populus, the pH of proportioning of the mechanical pulp being set at 6.8 to 7.2 and the machine pH at 7.1 to 7.5 and the conductivity of the pulp being set at 1000 to 1500 &mgr;S/cm. By using a relatively low pH value and a narrow pH range it is possible to diminish the sensitivity to disturbances of the paper making process. According to the present invention a mechanical aspen pulp can be combined with chemical pulp for preparing base paper of fine paper, whereby the mechanical pulp gives a high conductivity on the machine which improves the stability of the wet end and enhances water removal.

Abstract: The present invention concerns a method for producing a base paper for fine papers, the base paper being produced from a mixture of a mechanical pulp and a chemical pulp. The chemical pulp used comprises a chemical softwood pulp having a elastic modulus close to that of the mechanical pulp and a great bonding strength. It is preferred to use a chemical softwood pulp which produces a sheet having a elastic modulus of less than 6000 N/mm2 when the bonding strength is 400 J/m2. A pulp of this kind has a good ScottBond strength at the same light scattering. The base paper produced by the method can therefore be used in double-coated fine papers which require a large bonding strength of the base paper.

Abstract: The invention concerns a method for producing a paper web. According to the method a stock is produced from the fibrous raw material and the stock is formed to a web which is dried on a paper machine. According to the invention the stock is formed from a mechanical pulp prepared from wood material of the Populus family and from bleached chemical spruce pulp, whereby the amount of the mechanical pulp is 20 to 70 weight-% and the amount of the bleached chemical softwood pulp is 80 to 30 weight-% of the dry matter of the stock. It is preferred to use an aspen pulp, over 70% of the fiber fractions of which comprise fiber fractions +100, +200 and −200, and the proportion of the −200 fraction is 45% or less. A coated fine paper can be produced from the paper web whose properties are better than those of a traditional fine paper having the corresponding bulk and grammage, on the same capacity level the paper produced by the invention will give a yield gain of up to more than 20%.

Abstract: The present invention concerns a method for producing a base paper for fine papers, the base paper being produced from a mixture of a mechanical pulp and a chemical pulp. The chemical pulp used comprises a chemical softwood pulp having a elastic modulus close to that of the mechanical pulp and a great bonding strength. It is preferred to use a chemical softwood pulp which produces a sheet having a elastic modulus of less than 6000 N/mm2 when the bonding strength is 400 J/m2. A pulp of this kind has a good ScottBond strength at the same light scattering. The base paper produced by the method can therefore be used in double-coated fine papers which require a large bonding strength of the base paper.