Composition for the fluorescent whitening of paper

Abstract

Composition for the fluorescent whitening of paper, which comprises a) a fluorescent whitening agent (FWA) derived from 4,4′-bis[(1,3,5-triazin-2-yl)amino]stilbene-2,2′-disulphonic acid and characterized by one or both of the triazine rings carrying an —NH 2 substituent; b) water and c) optionally, further auxiliaries, the use thereof in either the pulp mass, in coating or in the metering size-press or film press and to a process thereto.

1 . A composition for the fluorescent whitening of paper or paperboard comprising 
 a) a fluorescent whitening agent (FWA) derived from 4,4′-bis[(1,3,5-triazin-2-yl)amino]stilbene-2,2′-disulphonic acid and characterized by one or both of the triazine rings carrying an —NH 2  substituent;    b) water and    c) optionally, further auxiliaries.    
     
     
         2 . A composition according to  claim 1 , comprising 
 5 to 50% by weight of the FWA component a),    50 to 95% by weight of water and    0 to 40% by weight of component c), each based on the total weight of the composition, wherein the sum of the components a) to c) amounts to 100%.    
     
     
         3 . A composition according to  claim 1 , in which the fluorescent whitening agent is a compound of the formula (I)  
       
         
           
           
               
               
           
         
       
       wherein 
 X 1 , X 2  and X 3  each, independent of the other, represent —NR 1 R 2  or —OR 3 , wherein  
 R 1  and R 2  are, independently of each other, 
 hydrogen, a C 1 -C 4 alkyl-group, which is unsubstituted or substituted by one or two of the following residues selected from the group consisting of C 1 -C 4 alkoxy, hydroxy, carboxy, cyano, A carbonamido, thiol, guanidine, substituted or unsubstituted phenyl, unsubstituted or C 1 -C 4 alkyl-substituted C 5 -C 8 cycloalkyl, halogen, a heterocycle and a sulphonic acid residue, and wherein the carbon chain of an alkyl group having two, three or four carbon atoms can be interrupted by oxygen,  
 or, alternatively,  
 R 1  and R 2 , together with the nitrogen atom linking them, complete a 5- or 6-membered heterocyclic ring;  
 
 R 3  represents C 1 -C 4 alkyl and  
 M represents H, Na, Li, K, Ca, Mg, ammonium, or ammonium that is mono-, di-, tri- or tetrasubstituted by C 1 -C 4 alkyl and/or C 2 -C 4 hydroxyalkyl.  
 
     
     
         4 . A composition according to  claim 3 , in which, in the compound of formula (I), 
 X 1  and X 2  each independently, represent —NH 2 , —NHC 1 -C 4 alkyl, —N(C 1 -C 4 alkyl) 2 , —NHC 2 —C 4 hydroxyalkyl, —N(C 2 -C 4 hydroxyalkyl) 2 , —N(C 1 -C 4 alkyl)(C 2 -C 4 hydroxyalkyl), —N H(C 2 -C 4 alkylene-C 1 -C 4 alkoxy), —N(C 2 -C 4 alkylene-C 1 -C 4 alkoxy) 2 , —NHC 1 -C 4 alkylphenyl, tetrahydrofurfurylamino, morpholino, piperidino, pyrrolidino or cyclohexylamino or an amino acid or amino acid amide-residue from which a hydrogen atom has been abstracted from the amino group and    X 3  represents —NH 2 .    
     
     
         5 . A composition according to  claim 4 , in which, in the compound of formula (I), X 1  and X 2  both represent —NH 2 , —NHC 1 -C 2 alkyl, —N(C 1 -C 2 alkyl) 2 , —NHCH 2 CH 2 OH, —N(CH 2 CH 2 OH) 2 , —N(C 1 -C 2 alkyl)(CH 2 CH 2 OH), —NHCH 2 CH 2 OCH 3 , —N(CH 2 CH 2 OCH 3 ) 2 , —NHCH 2 CH 2 —O—CH 2 CH 2 —OH, —N(CH 2 CH 2 —O—CH 2 CH 2 —OH), —NHCH 2 CO 2 M″, —N(CH 3 )CH 2 CO 2 M″, —NHCH 2 CH 2 CO 2 M″, —NHCH(CO 2 M″)CH 2 CH 2 CH 2 NHC(═NH)NH 2 , tetrahydrofurfurylamino, benzylamino, cyclohexylamino, pyrrolidino or morpholino and 
 M″ represents H, K, Na, ammonium or ammonium that is mono-, di-, tri- or tetra-substituted by C 1 -C 4 alkyl and/or C 2 -C 4 hydroxyalkyl.    
     
     
         6 . A process for the fluorescent whitening of paper or paperboard wherein the composition according to  claim 1  is applied to the paper in the pulp mass, in the form of a paper or paperboard coating composition, or directly in the metering size-press or in the film press.  
     
     
         7 . A process according to  claim 6 , wherein the composition is applied to the paper or paperboard in the form of a paper coating composition or directly in the metering size-press or in the film press.  
     
     
         8 . A process according to  claim 7 , wherein the composition is applied to the paper or paperboard directly in the metering size-press or in the film press.  
     
     
         9 . A process for the fluorescent whitening of paper or paperboard by treating the paper with a composition according to  claim 1 .  
     
     
         10 . Paper or paperboard, which has been whitened with a composition according to  claim 1 .  
     
     
         11 . A process for the fluorescent whitening of paper or paperboard comprising contacting the substrate with the florescent whitening agent composition according to  claim 1.