Thermal lamination adhesive coatings for use on substrates
Lamination adhesives including an aqueous dispersion having a mixture of a polyamide and an ethylene acrylic acid copolymer are provided for use on a variety of substrates. In various embodiments, the aqueous dispersion is substantially free of plasticizers and non-aqueous organic solvents. Also provided is a method of forming a laminate adhesion between two substrates. The disclosure also describes a laminate structure comprising first and second substrates laminated together by the lamination adhesive, the lamination adhesive including a mixture of a polyamide and a copolymer of ethylene and acrylic acid.
1. A lamination adhesive comprising:
an aqueous dispersion comprising a mixture of polyamide and a copolymer of ethylene and acrylic acid; and
an isocyanate crosslinker
wherein the lamination adhesive is substantially free of non-aqueous plasticizers and organic solvents.
2. The lamination adhesive of claim 1 , wherein the aqueous dispersion comprises from about 25% to about 70% by weight polyamide and from about 10% to about 30% by weight ethylene acrylic acid copolymer.
3. The lamination adhesive of claim 1 , wherein the aqueous dispersion comprises from about 25% to about 70% by weight polyamide.
4. The lamination adhesive of claim 1 , wherein the aqueous dispersion comprises from about 10% to about 30% by weight ethylene acrylic acid copolymer.
5. The lamination adhesive of claim 1 , wherein the aqueous dispersion further comprises polyurethane.
6. The lamination adhesive of claim 5 , wherein the aqueous dispersion comprises:
from about 25% to about 70% by weight polyamide;
from above 0% to about 70% by weight polyurethane; and
from about 10% to about 30% by weight ethylene acrylic acid copolymer.
7. The lamination adhesive of claim 1 , wherein the aqueous dispersion further comprises ammonia.
8. The lamination adhesive of claim 1 , wherein the solids comprise from about 1% to about 2% by weight isocyanate crosslinker.
9. The lamination adhesive of claim 1 , wherein the dispersion comprises from about 5% to about 40% by weight solids and from about 60% to about 95% weight water.
10. The lamination adhesive of claim 1 , wherein the copolymer of ethylene and acrylic acid comprises from about 65% to about 90% ethylene comonomers and from about 10% to about 35% acrylic acid comonomers.
11. The lamination adhesive of claim 1 , wherein the polyamide is an amine-terminated polyamide.
12. The lamination adhesive of claim 1 , wherein the lamination adhesive has a Brookfield dispersion viscosity of less than about 200 cps.
13. A lamination adhesive comprising:
an aqueous dispersion comprising:
from about 25% to about 70% by weight of a polyamide;
from about 10% to about 30% by weight of a copolymer of ethylene and acrylic acid; and
from about 0% to about 70% by weight polyurethane;
wherein the lamination adhesive is substantially free of non-aqueous plasticizers and organic solvents.
14. The lamination adhesive of claim 13 , wherein the aqueous dispersion further comprises ammonia.
15. The lamination adhesive of claim 13 , wherein the dispersion comprises from about 5% to about 40% by weight solids and from about 60% to about 95% weight water.
16. The lamination adhesive of claim 13 , wherein the copolymer of ethylene and acrylic acid comprises from about 65% to about 90% ethylene comonomers and from about 10% to about 35% acrylic acid comonomers.
17. The lamination adhesive of claim 13 , wherein the polyamide is an amine-terminated polyamide.
18. The lamination adhesive of claim 13 , wherein the lamination adhesive has a Brookfield dispersion viscosity of less than about 200 cps.
19. A lamination adhesive comprising an aqueous dispersion comprising a mixture of polyamide and a copolymer of ethylene and acrylic acid; wherein the lamination adhesive:
is substantially free of non-aqueous plasticizers and organic solvents; and
has a Brookfield dispersion viscosity of less than about 200 cps.
20. The lamination adhesive of claim 19 , wherein the aqueous dispersion comprises from about 25% to about 70% by weight polyamide and from about 10% to about 30% by weight ethylene acrylic acid copolymer.
21. The lamination adhesive of claim 19 , wherein the aqueous dispersion comprises from about 25% to about 70% by weight polyamide.
22. The lamination adhesive of claim 19 , wherein the aqueous dispersion comprises from about 10% to about 30% by weight ethylene acrylic acid copolymer.
23. The lamination adhesive of claim 19 , wherein the aqueous dispersion further comprises polyurethane.
24. The lamination adhesive of claim 19 , wherein the aqueous dispersion further comprises ammonia.
25. The lamination adhesive of claim 19 , wherein the dispersion comprises from about 5% to about 40% by weight solids and from about 60% to about 95% weight water.
26. The lamination adhesive of claim 19 , wherein the copolymer of ethylene and acrylic acid comprises from about 65% to about 90% ethylene comonomers and from about 10% to about 35% acrylic acid comonomers.
27. The lamination adhesive of claim 19 , wherein the polyamide is an amine-terminated polyamide.