Patent ID: 9441327
Filing Date: 2016-09-13
CPC Classification: D21H,Y10T

Claim Text:
1. A method of producing a paper having good dimensional stability, comprising the steps of: I. producing of a water-based impregnation mixture comprising at least a) a latex dispersed in the mixture, wherein the impregnation mixture has a pH of more than 7, or b) a dry strength agent, wherein the impregnation mixture has a pH of at least 6 and at most 7, II. lowering of the pH of the impregnation mixture to at most 5.5 by addition of a coagulant releasing aluminum ions, and III. raising the pH at least to the values indicated in step I) for alternative a) or b), respectively, and IV. impregnating a raw paper with the impregnation mixture of step III).