Coated paper possessing silky feel

Abstract

The present invention relates to a coating composition for coated papers intended to be printed in offset, characterized in that the coating pigments are polyurethane microbeads having a size of less than 10 micrometers and advantageously of approximately 7 micrometers. It also relates to a paper having a silky feel, comprising at least one face coated with said coating composition and advantageously these two faces. This paper is also characterized in that it can be printed in offset with low, indeed even nonexistent, setting-off and chalking.

1 . A coating composition for coated papers intended to be printed in offset comprising pigments and a binder, wherein the coating pigments are polyurethane microbeads having a size of less than 10 micrometers.  
     
     
         2 . The coating composition as claimed in  claim 1 , wherein the binder used is an aqueous emulsion of polyurethane.  
     
     
         3 . The coating composition as claimed in  claim 2 , wherein the level of binder with respect to the pigments is greater than or equal to 40% by weight.  
     
     
         4 . A paper having a silky feel, comprising at least one face coated with a coating composition as claimed in  claim 1 .  
     
     
         5 . The paper as claimed in  claim 4 , wherein the coefficient of dynamic friction between the coated recto face and the other verso face, also coated, of this paper is less than or equal to 1.0, which measurement is carried out according to the standard NF-Q-03-082 with a block weighing 200 g.  
     
     
         6 . The paper as claimed in  claim 4 , wherein the weight of the coating applied to at least one face is between 2 and 10 g/m 2  by dry weight.  
     
     
         7 . The paper as claimed in  claim 4 , wherein it constitutes a tracing paper, obtained in particular by hard beating of the cellulose fibers of which it is composed.  
     
     
         8 . The paper as claimed in  claim 1 , wherein the polyurethane microbeads have a size of approximately 7 micrometers.  
     
     
         9 . The coating composition as claimed in  claim 2 , wherein the binder has a degree of elongation of greater than or equal to 500%.  
     
     
         10 . The coating composition as claimed in  claim 3 , wherein the level of binder with respect to the pigments is greater than or equal to 200%.  
     
     
         11 . The paper as claimed in  claim 4 , wherein the two faces are coated with the coating composition.  
     
     
         12 . The paper as claimed in  claim 6 , wherein the weight of the coating applied to the at least one face is between 3 and 6 g/m 2 .  
     
     
         13 . The paper as claimed in  claim 5 , wherein the weight of the coating applied to at least one face is between 2 and 10 g/m 2  by dry weight.  
     
     
         14 . A paper having a silky feel, comprising at least one face coated with a coating composition as claimed in  claim 2 .  
     
     
         15 . The paper as claimed in  claim 14 , wherein the coefficient of dynamic friction between the coated recto face and the other verso face, also coated, of this paper is less than or equal to 1.0, which measurement is carried out according to the standard NF-Q-03-082 with a block weighing 200 g.  
     
     
         16 . The paper as claimed in  claim 14 , wherein the weight of the coating applied to at least one face is between 2 and 10 g/m 2  by dry weight.  
     
     
         17 . The paper as claimed in  claim 14 , wherein it constitutes a tracing paper, obtained in particular by hard beating of the cellulose fibers of which it is composed.  
     
     
         18 . A paper having a silky feel, comprising at least one face coated with a coating composition as claimed in  claim 3 .  
     
     
         19 . The paper as claimed in  claim 18 , wherein the coefficient of dynamic friction between the coated recto face and the other verso face, also coated, of this paper is less than or equal to 1.0, which measurement is carried out according to the standard NF-Q-03-082 with a block weighing 200 g.  
     
     
         20 . The paper as claimed in  claim 18 , wherein the weight of the coating applied to at least one face is between 2 and 10 g/m 2  by dry weight.