Novel water-resistant, repulpable and hydrophilic paper having a soft feel

Abstract

Novel water-resistant, repulpable and hydrophilic papers having a soft feel are prepared from paper pulps containing at least one resin (A) which improves the wet strength thereof and, optionally, at least one wet strength promoter (B), the paper pulps or papers prepared therefrom having been treated with a composition (D) comprising at least one polyorganosiloxane (C) which contains, per molecule, at least one siloxyl unit substituted by at least one functional group V directly bonded to a silicon atom, such functional group V comprising sterically hindered piperidinyl functional group(s).

What is claimed is:  
     
         1 . Water-resistant, repulpable and hydrophilic paper having a soft feel comprising an effective amount of at least one resin (A) which improves the wet strength thereof, optionally, at least one wet strength promoter (B), and at least one polyorganosiloxane (C) which comprises, per molecule, at least one siloxyl unit substituted by at least one functional group V directly bonded to a silicon atom, the functional group V being a group with sterically hindered piperidinyl functional group(s) selected from the group consisting of the: 
 (a) groups of formula (I):                          in which formula R 4  is a divalent hydrocarbonaceous radical selected from among:    linear or branched alkylene radicals having 2 to 18 carbon atoms;    alkylenecarbonyl radicals, the linear or branched alkylene moiety of which having 2 to 20 carbon atoms;    alkylenecyclohexylene radicals, the linear or branched alkylene moiety of which having 2 to 12 carbon atoms and the cyclohexylene moiety of which comprises an OH group and optionally 1 or 2 alkyl radicals having 1 to 4 carbon atoms;    radicals of formula —R 7 —O—R 7 — in which the R 7  radicals, which may be identical or different, are each an alkylene radical having 1 to 12 carbon atoms;    radicals of formula —R 7 —O—R 7 — in which the R 7  radicals are as defined above and one of them or both are substituted by one or two —OH group(s);    radicals of formula —R 7 —COO—R 7 — in which the R 7  radicals are as defined above;    radicals of formula —R 8 —O—R 9 —O—CO—R 8 — in which the R 8  and R 9  radicals, which may be identical or different, are each an alkylene radical having 2 to 12 carbon atoms and the R 9  radical is optionally substituted by a hydroxyl radical; U represents —O— or —NR 10 -, in which R 10  is a hydrogen atom, a linear or branched alkyl radical having 1 to 6 carbon atoms or a divalent radical of formula:                          in which R 4  is as defined above, R 5  and R 6  are as defined below and R 11  is a linear or branched divalent alkylene radical having from 1 to 12 carbon atoms, one of the valency bonds (that of R 11 ) being connected to the atom of —NR 10 — and the other (that of R 4 ) being connected to a silicon atom; the R 5  radicals, which may be identical or different, are each a linear or branched alkyl radical having 1 to 3 carbon atoms or a phenyl radical; and the R 6  radical is a hydrogen atom or R 5  or 0; and    (b) groups of formula (II):                          in which formula R′ 4  is a trivalent radical of formula:                          where m represents a number from 2 to 20, or a trivalent radical of formula:                          where p represents a number from 2 to 20; U′ represents —O— or —NR 12 —, in which R 12  is a hydrogen atom or a linear or branched alkyl radical having 1 to 6 carbon atoms; and R 5  and R 6  have the same meanings as in formula (I).    
     
     
         2 . Water-resistant, repulpable and hydrophilic paper having a soft feel prepared from a paper pulp comprising an effective amount of at least one resin (A) which improves the wet strength thereof, and, optionally, at least one wet strength promoter (B), said paper pulp or said paper prepared therefrom having been treated with a composition (D) which comprises at least one polyorganosiloxane (C) containing, per molecule, at least one siloxyl unit substituted by at least one functional group V directly bonded to a silicon atom, the functional group V being a group with sterically hindered piperidinyl functional group(s) selected from the group consisting of the: 
 (a) groups of formula (I):                          in which formula R 4  is a divalent hydrocarbonaceous radical selected from among:    linear or branched alkylene radicals having 2 to 18 carbon atoms;    alkylenecarbonyl radicals, the linear or branched alkylene moiety of which having 2 to 20 carbon atoms;    alkylenecyclohexylene radicals, the linear or branched alkylene moiety of which having 2 to 12 carbon atoms and the cyclohexylene moiety of which comprises an OH group and optionally 1 or 2 alkyl radicals having 1 to 4 carbon atoms;    radicals of formula —R 7 —O—R 7 — in which the R 7  radicals, which may be identical or different, are each an alkylene radical having 1 to 12 carbon atoms;    radicals of formula —R 7 —O—R 7 — in which the R 7  radicals are as defined above and one of them or both are substituted by one or two —OH group(s);    radicals of formula —R 7 —COO—R 7 — in which the R 7  radicals are as defined above;    radicals of formula —R 8 —O—R 9 —O—CO—R 8 — in which the R 8  and R 9  radicals, which may be identical or different, are each an alkylene radical having 2 to 12 carbon atoms and the R 9  radical is optionally substituted by a hydroxyl radical; U represents —O— or —NR 10 -, in which R 10  is a hydrogen atom, a linear or branched alkyl radical having 1 to 6 carbon atoms or a divalent radical of formula:                          in which R 4  is as defined above, R 5  and R 6  are as defined below and R 11  is a linear or branched divalent alkylene radical having from 1 to 12 carbon atoms, one of the valency bonds (that of R 11 ) being connected to the atom of —NR 10 — and the other (that of R 4 ) being connected to a silicon atom; the R 5  radicals, which may be identical or different, are each a linear or branched alkyl radical having 1 to 3 carbon atoms or a phenyl radical; and the R 6  radical is a hydrogen atom or R 5  or 0; and    (b) groups of formula (II):                          in which formula R′ 4  is a trivalent radical of formula:                          where m represents a number from 2 to 20, or a trivalent radical of formula:                          where p represents a number from 2 to 20; U′ represents —O— or —NR 12 —, in which R 12  is a hydrogen atom or a linear or branched alkyl radical having 1 to 6 carbon atoms; and R 5  and R 6  have the same meanings as in formula (I).    
     
     
         3 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , said at least one functional group V having the formula (I).  
     
     
         4 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , said at least one functional group V having the formula (II).  
     
     
         5 . The water-resistant, repulpable and hydrophilic paper as defined by  claim 2 , said paper pulp having been treated with the composition (D).  
     
     
         6 . The water-resistant, repulpable and hydrophilic paper as defined by  claim 2 , the final paper having been treated with the composition (D).  
     
     
         7 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , said at least one polyorganosiloxane comprising siloxyl structural units having the formula (III):  
       
         
           
           
               
               
           
         
       
       in which formula: 
 (1) the symbols Z, which may be identical or different, represent R 1  and/or V;  
 (2) the symbols R 1 , R 2  and R 3 , which may be identical or different, each represent an optionally substituted, linear or branched C 1 -C 12  alkyl radical, an optionally substituted C 5 -C 10  cycloalkyl radical, an optionally substituted C 6 -C 18  aryl radical, an optionally substituted aralkyl radical or an —OR 13  radical wherein R 13  represents a hydrogen atom, a linear, branched or cyclic alkyl radical having from 1 to 15 carbon atoms or a hydrocarbonaceous group comprising an epoxide and/or polyether functional group;  
 (3) the symbols V are as defined above; and  
 (4) the number of siloxyl units without a V group ranges from 1 and 800, the number of siloxyl units with a V group ranges from 1 and 20, and 0≦w≦10 and 8≦y≦798.  
 
     
     
         8 . The water-resistant, repulpable and hydrophilic paper as defined by  claim 7 , the polyorganosiloxane (C) of formula (III) being linear (w=0) and the symbols R 1 , R 2  and R 3  of the formula (III) being methyl radicals.  
     
     
         9 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , wherein said polyorganosiloxane (C) having the formula (I) or (II), the radical R 5  are methyl radicals.  
     
     
         10 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , said at least one polyorganosiloxane comprising siloxyl structural units having the formula (IV):  
       
         
           
           
               
               
           
         
       
       in which formula: 
 the various units are randomly distributed in the chain;  
 p represents a number greater than or equal to 0;  
 r represents a number greater than or equal to 0;  
 q represents a number greater than or equal to 1;  
 R′ 1  represents a linear or branched alkyl radical having 1 to 18 carbon atoms;  
 the U, R 4  and R 6  groups are as defined above.  
 
     
     
         11 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , said at least one resin (A) comprising a polyamidoamine-epichlorohydrin (PAE) cationic resin.  
     
     
         12 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , prepared from a cellulosic paper pulp.  
     
     
         13 . A process for the preparation of a water-resistant, repulpable and hydrophilic paper having a soft feel as defined by claims  1  or  2 , comprising wet shaping a paper pulp thereof, said paper pulp or said paper prepared therefrom having been treated with a composition (D) which comprises at least one polyorganosiloxane (C) containing, per molecule, at least one siloxyl unit substituted by at least one functional group V directly bonded to a silicon atom, the functional group V being a group with sterically hindered piperidinyl functional group(s) selected from the group consisting of the: 
 (a) groups of formula (I):  
                     
 in which formula R 4  is a divalent hydrocarbonaceous radical selected from among:  
 linear or branched alkylene radicals having 2 to 18 carbon atoms;  
 alkylenecarbonyl radicals, the linear or branched alkylene moiety of which having 2 to 20 carbon atoms;  
 alkylenecyclohexylene radicals, the linear or branched alkylene moiety of which having 2 to 12 carbon atoms and the cyclohexylene moiety of which comprises an OH group and optionally 1 or 2 alkyl radicals having 1 to 4 carbon atoms;  
 radicals of formula —R 7 —O—R 7 — in which the R 7  radicals, which may be identical or different, are each an alkylene radical having 1 to 12 carbon atoms;  
 radicals of formula —R 7 —O—R 7 — in which the R 7  radicals are as defined above and one of them or both are substituted by one or two —OH group(s);  
 radicals of formula —R 7 —COO—R 7 — in which the R 7  radicals are as defined above;  
 radicals of formula —R 8 —O—R 9 —O—CO—R 8 — in which the R 8  and R 9  radicals, which may be identical or different, are each an alkylene radical having 2 to 12 carbon atoms and the R 9  radical is optionally substituted by a hydroxyl radical; U represents —O— or —NR 10 -, in which R 10  is a hydrogen atom, a linear or branched alkyl radical having 1 to 6 carbon atoms or a divalent radical of formula:  
                     
 in which R 4  is as defined above, R 5  and R 6  are as defined below and R 11  is a linear or branched divalent alkylene radical having from 1 to 12 carbon atoms, one of the valency bonds (that of R 11 ) being connected to the atom of —NR 10 — and the other (that of R 4 ) being connected to a silicon atom; the R 5  radicals, which may be identical or different, are each a linear or branched alkyl radical having 1 to 3 carbon atoms or a phenyl radical; and the R 6  radical is a hydrogen atom or R 5  or 0; and  
 (b) groups of formula (II):  
                     
 in which formula R′ 4  is a trivalent radical of formula:  
                     
 where m represents a number from 2 to 20, or a trivalent radical of formula:  
                     
 where p represents a number from 2 to 20; U′ represents —O— or —NR 12 —, in which R 12  is a hydrogen atom or a linear or branched alkyl radical having 1 to 6 carbon atoms; and R 5  and R 6  have the same meanings as in formula (I).  
 
     
     
         14 . The process as defined by  claim 13 , said at least one resin (A) comprising a polyamidoamine-epichlorohydrin (PAE) cationic resin.  
     
     
         15 . The process as defined by  claim 13 , the paper having been prepared from a cellulosic pulp.  
     
     
         16 . The water-resistant, repulpable and hydrophilic paper as defined by  claim 2 , said composition (D) comprising an aqueous solution, dispersion or emulsion.  
     
     
         17 . The water-resistant, repulpable and hydrophilic paper as defined by claims  1  or  2 , comprising a paper towel, toilet paper, household or sanitary absorbent paper, or paper handkerchief.