초록 ▼

The invention relates to a process for regulating the porosity and printing properties of paper, in particular uncoated wood-containing paper such as SC-paper, wherein a sufficient quantity of colloidal PCC having a BET surface area of 10-100 m2/g is used as a filter in the paper to achieve a desire

The invention relates to a process for regulating the porosity and printing properties of paper, in particular uncoated wood-containing paper such as SC-paper, wherein a sufficient quantity of colloidal PCC having a BET surface area of 10-100 m2/g is used as a filter in the paper to achieve a desired porosity of the paper; as well as paper containing colloidal PCC as filler, and a pigment mixture suitable for paper manufacture and containing colloidal PCC.

대표청구항 ▼

1. A process for regulating the porosity and printing properties of uncoated wood-containing paper, having at least 10% by weight of the pulp being lignin-containing pulp, the process comprising using a sufficient quantity of colloidal precipitated calcium carbonate (PCC) having a BET surface area o

1. A process for regulating the porosity and printing properties of uncoated wood-containing paper, having at least 10% by weight of the pulp being lignin-containing pulp, the process comprising using a sufficient quantity of colloidal precipitated calcium carbonate (PCC) having a BET surface area of 10-100 m2/g as a filler to achieve a desired porosity of the paper.2. The process according to claim 1 wherein the paper is SC paper, and wherein colloidal PCC is used in a quantity sufficient to achieve a porosity of at most 0.30 μm/Pas.3. The process according to claim 2, wherein the paper is SC-A paper.4. The process according to claim 1 wherein the paper is SC-B paper, and wherein colloidal PCC is used in a quantity sufficient to achieve a porosity of at most 0.60 μm/Pas.5. The process according to claim 1 wherein the paper is newsprint, and wherein colloidal PCC is used in an amount sufficient to achieve a porosity of at most 20 μm/Pas.6. The process according to claim 1 wherein the colloidal PCC has a BET surface area of 15-50 m2/g.7. The process according to claim 6 wherein the colloidal PCC has a BET surface area of 20-30 m2/g.8. The process according to claim 1 wherein colloidal PCC is incorporated into the paper in an amount of at least about 1% by weight based on the total weight of the paper.9. The process according to claim 8 wherein colloidal PCC is incorporated into the paper in an amount of at least about 2% by weight based on the total weight of the paper.10. An uncoated wood-containing paper in which at least 10% by weight of the pulp is lignin-containing pulp, and wherein said paper further contains colloidal precipitated calcium carbonate (PCC).11. The paper according to claim 10 containing colloidal PCC having a BET surface area of 10-100 m2/g as a filler.12. The paper according to claim 11 comprising at least one further filler selected from the group consisting of non-colloidal PCC, kaolin, calcined kaolin, gypsum, chalk, ground marble, silicate-containing minerals, sulphate-containing minerals, oxide-containing minerals, carbonate-containing minerals, hydroxide-containing minerals, calcium sulfoaluminates, plastic particles and organic pigments.13. The paper according to claim 11 wherein the colloidal PCC has a BET surface area of 15-50 m2/g.14. The paper according to claim 10 wherein the colloidal PCC is present in an amount of at least about 1% by weight based on the total weight of the paper.15. The paper according to claim 14 comprising at least one further filler selected from the group consisting of non-colloidal PCC, kaolin, calcined kaolin, gypsum, chalk, ground marble, silicate-containing minerals, sulphate-containing minerals, oxide-containing minerals, carbonate-containing minerals, hydroxide-containing minerals, calcium sulfoaluminates, plastic particles and organic pigments.16. The paper according to claim 14 wherein the colloidal PCC has a BET surface area of 10-100 m2/g.17. The paper according to claim 10, wherein the paper is a SC paper containing colloidal PCC and having a porosity of at most 0.30 μm/Pas.18. The paper according to claim 10, wherein the paper is a SC-A paper.19. The paper according to claim 10, wherein the paper is a SC-B paper containing colloidal PCC and having a porosity of at most 0.60 μm/Pas.20. The paper according to claim 10, wherein the paper is a newsprint containing colloidal PCC and having a porosity of at most 20 μm/Pas.