Fluting or liner comprising nssc pulp

Abstract

The present invention relates to a fluting or liner for corrugated board comprising a neutral sulfite semi chemical (NSSC) pulp, wherein said NSSC pulp has an ash content of less than 1.8 wt %, as determined according to standard ISO 1762:2019. The invention further relates to a corrugated board comprising the fluting and/or liner.

1 . A fluting or liner for corrugated board comprising:
 a neutral sulfite semi chemical (NSSC) pulp,   wherein said NSSC pulp has an ash content of less than 1.8 wt %, as determined according to standard ISO 1762:2019.   
     
     
         2 . The fluting or liner according to  claim 1 , wherein said NSSC pulp has been subjected to washing to reduce the ash content. 
     
     
         3 . The fluting or liner according to  claim 1 , wherein said ash content is less than 1.6 wt %, as determined according to standard ISO 1762:2019. 
     
     
         4 . The fluting or liner according to  claim 1 , wherein said NSSC pulp has a hot water extract conductivity of less than 5 mS/cm, as determined according to ISO 6587. 
     
     
         5 . The fluting or liner according to  claim 1 , further comprising:
 at least one internal sizing agent.   
     
     
         6 . The fluting or liner according to  claim 5 , wherein the at least one internal sizing agent is selected from a group consisting of: alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), rosin sizes, and mixtures thereof. 
     
     
         7 . The fluting or liner according to  claim 5 , wherein an amount of the at least one internal sizing agent in the fluting or liner is in a range of 0.5-6 kg/tn, based on dry weight. 
     
     
         8 . The fluting or liner according to  claim 1 , further comprising:
 a microparticle retention aid system.   
     
     
         9 . The fluting or liner according to  claim 8 , wherein microparticles of the microparticle retention aid system are selected from a group consisting of: silica microparticles, bentonite microparticles, and cellulose nanoparticles. 
     
     
         10 . The fluting or liner according to  claim 8 , wherein the microparticle retention aid system comprises a water soluble polymer. 
     
     
         11 . The fluting or liner according to  claim 1 , wherein at least one side of the fluting or liner has a Cobb (60 s) value below 40 gsm, as determined according to standard ISO 535. 
     
     
         12 . The fluting or liner according to  claim 1 , wherein said fluting or liner comprises less than 10 wt of recycled fibers. 
     
     
         13 . The fluting or liner according to  claim 1 , wherein said fluting or liner has a hot water extract conductivity of less than 15 mS/cm, as determined according to ISO 6587. 
     
     
         14 . The fluting or liner according to  claim 1 , wherein said fluting or liner has an equilibrium moisture content (EMC) of less than 10 wt %, at 50% RH, as determined according to standard ISO 287. 
     
     
         15 . The fluting or liner according to  claim 1 , wherein said fluting or liner has a cd/md stretch value greater than 1.8, as determined according to standard ISO 1924-3. 
     
     
         16 . The fluting or liner according to  claim 1 , wherein said fluting has a kinetic friction of less than 0.5, as determined according to standard ASTMD 1894-63 
     
     
         17 . A corrugated board comprising:
 the fluting, and/or the liner according to  claim 1 .