Water-based adhesive for the bonding of cellulose based substrates
Water-based adhesive composition comprising: from 30% to 60% by weight (expressed as dry content) of a chloroprene modified acrylic emulsion (A); and from 0.05% to 0.45% by weight (expressed as dry content) of a water soluble polymer (B) selected among xanthan gum and konjac gum; said composition being obtainable by a process (P) comprising a first step (i) of dissolving into water polymer (B) in the form of a powdered solid. Use of said composition, for the bonding of at least one cellulose based substrate.
1. A water-based adhesive composition comprising, on the basis of its total weight:
from 30% to 60% by weight (expressed as dry content) of a chloroprene modified acrylic emulsion (A); and
from 0.05% to 0.45% by weight (expressed as dry content) of a water soluble polymer (B) that is xanthan gum or konjac gum;
said composition being obtained by a process (P) comprising a first (i) dissolving into water polymer (B) in the form of a powdered solid, so as to obtain a composition (S) consisting essentially of a water solution of polymer (B).
2. The water-based adhesive composition according to claim 1 , having a viscosity at room temperature of 150 to 5000 mPas·s.
3. The water-based adhesive composition according to claim 1 , having a viscosity at room temperature of 200 to 4000 mPa·s.
4. The water-based adhesive composition according to claim 1 , wherein the chloroprene modified acrylic emulsion (A) is an aqueous dispersion comprising polychloroprene and at least one polymer (C) obtained starting from one or more monomers that are meth(acrylic) acid, meth(acrylate)esters, styrene or acrylonitrile.
5. The water-based adhesive composition according to claim 4 , wherein the chloroprene modified acrylic emulsion (A) is an aqueous dispersion of polychloroprene and polymer (C), both forming an interpenetrating polymer network.
6. The water-based adhesive composition according to claim 1 , having a content of chloroprene modified acrylic emulsion (A) of 35% to 55%.
7. The water-based adhesive composition according to claim 1 , wherein the water soluble polymer (B) is xanthan gum.
8. The water-based adhesive composition according to claim 1 , wherein the water soluble polymer (B) is Konjac gum.
9. A method for bonding of at least one cellulose based substrate, comprising bonding said cellulose based substrate to an additional substrate using the water-based adhesive composition of claim 1 .
10. The method according to claim 9 , wherein the cellulose based substrate is cardboard, paper or cellulose based nonwoven fabrics.
11. The method according to claim 9 , wherein the cellulose based substrate is a glossy paper having one face coated with a UV primer.
12. The method according to claim 9 , wherein the cellulose based substrate is bonded to a non cellulose based substrate.
13. A method according to claim 9 , wherein the substrate is part of an assembly of cardboards in the rigid packing industry or in the bookbinding and/or graphic arts industry.
14. The method according to claim 11 , wherein the UV primer is an acrylic primer.
15. The method according to claim 12 , wherein the cellulose based substrate is bonded to a PolyVinylChloride (PVC) film, PolyEthyleneTerephtalate (PET) film or a low surface tension plastic film.