Dispersion adhesives

Abstract

The invention relates to the use of aqueous dispersion adhesives on the basis of a mixture of aqueous polyurethane or polyurethane-urea dispersions for bonding foam substrates according to the spray coagulation method.

1 - 9 . (canceled) 
     
     
         10 . An adhesive-bonded foam substrates comprising:
 a foam substrate;   a second substrate; and   an adhesive composition applied to bond the foam substrate to the second substrate,   wherein the adhesive composition comprises:
 an aqueous dispersion comprising a mixture of: 
 A) an aqueous polyurethane or polyurethane-urea dispersion comprising
 I. a polymer A) formed from
 I (i). at least one difunctional aliphatic polyester polyol having a molecular weight of 400 to 5000 q/mol, 
 I (ii). at least one mixture of hexamethylene diisocyanate (HDI) and 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI), and 
 I (iii). at least one mixture of two or more aminic chain extenders, wherein at least one compound bears an ionic group, 
 and the polymer A) after drying is semicrystalline or crystalline with a glass transition at a glass transition temperature Tq of between −65° C. and −40° C., and 
 
 
 B) an aqueous polyurethane or polyurethane-urea dispersion which differs from A) and contains
 II. a polymer B) formed from
 II(i). at least one difunctional aromatic polyester polyol having a molecular weight of 400 to 5000 q/mol, 
 II (ii). at least one difunctional polyol component having a molecular weight of 62 to 399, 
 II (iii). at least one aliphatic diisocyanate and 
 II (iv). at least one aminic chain extender having an ionic group, 
 
 wherein the polymer B) after drying is amorphous with a glass transition at a glass transition temperature Tq of between −15° C. and +10° C.: 
 
   and wherein the mixture contains 34.8% to 90.2% by weight of polymer A) and 9.8% to 65.2% by weight of polymer B), based on the sum total of polymers A) and B).   
     
     
         11 . The adhesive-bonded foam substrate according to  claim 10 , wherein the second substrate is a second foam substrate. 
     
     
         12 . The adhesive-bonded foam substrate according to  claim 10 , wherein the mixture contains 44.4% to 87.8% by weight of polymer A) and 12.2% to 55.6% by weight of polymer B). 
     
     
         13 . The adhesive-bonded foam substrate according to  claim 10 , wherein the mixture contains 54.5% to 81.9% by weight of polymer A) and 18.1% to 45.5% by weight of polymer B). 
     
     
         14 . The adhesive-bonded foam substrate according to  claim 10 , wherein an HDI:IPDI molar ratio is between 9:1 and 1:9. 
     
     
         15 . The adhesive-bonded foam substrate according to  claim 10 , wherein an HDI:IPDI molar ratio is between 3:1 and 1:3. 
     
     
         16 . The adhesive-bonded foam substrate according to  claim 10 , wherein component A) I(iii). is a mixture of diethanolamine and a sodium salt of N-(2-aminoethyl)-2-aminoethanesulfonic acid. 
     
     
         17 . The adhesive-bonded foam substrate according to  claim 10 , wherein component B) II(i). is a polyester polyol based on o-phthalic acid, o-phthalic anhydride and butane-1,4-diol or hexane-1,6-diol. 
     
     
         18 . A process for preparing an aqueous dispersion, comprising:
 mixing A) an aqueous polyurethane or polyurethane-urea dispersion with B) an aqueous polyurethane or polyurethane-urea dispersion that differs from A) to form a mixture, wherein
 A) the aqueous polyurethane or polyurethane-urea dispersion comprises
 I. a polymer A) formed from
 I (i). at least one difunctional aliphatic polyester polyol having a molecular weight of 400 to 5000 g/mol, 
 I (ii). at least one mixture of hexamethylene diisocyanate (HDI) and 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI), and 
 I (iii). at least one mixture of two or more aminic chain extenders, wherein at least one compound bears an ionic group, 
 and the polymer A) after drying is semicrystalline or crystalline with a glass transition at a glass transition temperature Tg of between −65° C. and −40° C., and 
 
 
 B) the aqueous polyurethane or polyurethane-urea dispersion that differs from A) comprises
 II. a polymer B) formed from
 II (i). at least one difunctional aromatic polyester polyol having a molecular weight of 400 to 5000 g/mol, 
 II (ii). at least one difunctional polyol component having a molecular weight of 62 to 399, 
 II (iii). at least one aliphatic diisocyanate and 
 II (iv). at least one aminic chain extender having an ionic group, 
 
 wherein the polymer B) after drying is amorphous with a glass transition at a glass transition temperature Tg of between −15° C. and +10° C., 
 
   and wherein the mixture comprises 34.8% to 90.2% by weight of polymer A) and 9.8% to 65.2% by weight of polymer B), based on a sum total of polymers A) and B).