Cellulosic product and process for its production

Abstract

The present invention relates to a process for the production of a cellulosic product which comprises (i) providing an aqueous cellulosic suspension; (ii) adding to the suspension a clay having 3R 2 stacking; and (iii) dewatering the obtained suspension. The invention also relates to a process for the production of a cellulosic product which comprises (i) providing an aqueous cellulosic suspension; (ii) adding to the suspension a cationic clay; (iii) adding to the suspension one or more drainage and retention aids comprising at least one cationic polymer; and (iv) dewatering the obtained suspension. The invention further relates to a cellulosic product comprising clay having 3R 2 stacking.

1 .- 8 . (canceled)  
   
   
       9 . A process for the production of paper which comprises 
 (i) providing an aqueous cellulosic suspension;    (ii) adding to the suspension a clay having 3R 2  stacking, the clay being added in an amount of at least about 0.01% by weight, calculated as dry clay on dry cellulosic suspension; and    (iii) dewatering the obtained suspension.    
   
   
       10 . The process according to  claim 9 , wherein the clay is cationic.  
   
   
       11 . The process according to  claim 9 , wherein the clay is hydrotalcite.  
   
   
       12 . The process according to  claim 9 , wherein it further comprises adding to the suspension one or more drainage and retention aids.  
   
   
       13 . The process according to  claim 12 , wherein the drainage and retention aids comprise cationic polymer and anionic material.  
   
   
       14 . The process according to  claim 13 , wherein the drainage and retention aids comprise cationic polymer and anionic silica-based particles.  
   
   
       15 . The process according to  claim 13 , wherein the drainage and retention aids comprise cationic polymer and anionic clay of smectite type.  
   
   
       16 . The process according to  claim 12 , wherein the drainage and retention aids comprise cationic and anionic organic polymers.  
   
   
       17 . The process according to  claim 13 , wherein the cationic polymer is cationic starch or cationic acrylamide-based polymer.  
   
   
       18 . The process according to  claim 16 , wherein the cationic polymer is cationic starch or cationic acrylamide-based polymer.  
   
   
       19 . The process according to  claim 13 , wherein the cationic polymer contains one or more aromatic groups.  
   
   
       20 . The process according to  claim 9 , wherein it further comprises adding to the suspension one or more sizing agents.  
   
   
       21 . A process for the production of paper which comprises 
 (i) providing an aqueous cellulosic suspension;    (ii) adding to the suspension a cationic clay in an amount of at least about 0.01% by weight, calculated as dry clay on dry cellulosic suspension;    (iii) adding to the suspension one or more drainage and retention aids comprising at least one cationic polymer, the cationic polymer being added in an amount of at least about 0.001% by weight, based on dry cellulosic suspension,    (iv) dewatering the obtained suspension.    
   
   
       22 . The process according to  claim 21 , wherein the clay has 3R 2  stacking.  
   
   
       23 . The process according to  claim 21 , wherein the drainage and retention aids comprise cationic polymer and anionic silica-based particles.  
   
   
       24 . The process according to  claim 23 , wherein the silica-based particles have a specific surface area above 100 m 2 /g  
   
   
       25 . The process according to  claim 23 , wherein the silica-based particles are present in a sol having an S-value in the range of from 8 to 50%,  
   
   
       26 . The process according to  claim 21 , wherein the drainage and retention aids comprise cationic polymer and anionic clay of smectite type.  
   
   
       27 . The process according to  claim 21 , wherein the drainage and retention aids comprise cationic and anionic organic polymers.  
   
   
       28 . The process according to  claim 21 , wherein the cationic polymer is cationic starch or cationic acrylamide-based polymer.  
   
   
       29 . The process according to  claim 23 , wherein the cationic polymer is cationic starch or cationic acrylamide-based polymer.  
   
   
       30 . The process according to  claim 21 , wherein the cationic polymer contains one or more aromatic groups.  
   
   
       31 . The process according to  claim 21 , wherein it further comprises adding to the suspension one or more sizing agents.  
   
   
       32 . The process according to  claim 21 , wherein the cellulosic suspension contains filler.  
   
   
       33 . A process for the production of paper which comprises 
 (i) providing an aqueous suspension containing cellulosic fibres, and optional filler;    (ii) adding to the suspension a cationic clay having 3R 2  stacking, the clay being added in an amount of at least about 0.01% by weight, calculated as dry clay on dry suspension;    (iii) adding to the suspension at least one cationic polymer in an amount of at least about 0.001% by weight, based on dry suspension;    (iv) adding to the suspension anionic silica-based particles in an amount of at least about 0.001% by weight, based on dry suspension; and    (v) dewatering the obtained suspension.    
   
   
       34 . The process according to  claim 33 , wherein it further comprises adding to the suspension one or more sizing agents.  
   
   
       35 .- 40 . (canceled)