Neutral aqueous wax emulsions
View Patent ↗Wax emulsions for the manufacture of wallboard include water; a lignosulfonic acid or a salt thereof; and at least one wax selected from the group consisting of slack wax, paraffin wax and montan wax. The emulsions may have a pH of between about 6.5 and 7.9. Such emulsions can provide enhanced moisture resistance to the wallboard.
1. A wax emulsion for manufacture of wallboard, comprising:
water;
a lignosulfonic acid or a salt thereof;
at least one wax selected from the group consisting of slack wax and paraffin wax; and
a stabilizer consisting essentially of an ethylene-vinyl alcohol-vinyl acetate terpolymer.
2. The wax emulsion of claim 1 , wherein the wax emulsions has a pH of between about 6.5 and about 7.9.
3. The wax emulsion of claim 1 , wherein the wax emulsion has a pH of between about 7.4 and about 7.7.
4. The wax emulsion of claim 1 , wherein the solids content of the wax emulsion is about 30% to about 60% by weight of the emulsion.
5. The wax emulsion of claim 1 wherein the at least one wax comprises slack wax.
6. The wax emulsion of claim 1 , wherein the emulsion comprises water in an amount of about 40% to about 70% by weight of the emulsion.
7. The wax emulsion of claim 1 , wherein the emulsion comprises a stabilizer in an amount of 0.1% to about 5% by weight of the emulsion.
8. The wax emulsion of claim 1 , wherein the emulsion comprises lignosulfonic acid or a salt thereof in an amount of about 0.1% to about 5% by weight of the emulsion.
9. The wax emulsion of claim 1 , wherein the emulsion comprises the at least one wax in an amount of about 40% to about 60% by weight of the emulsion.
10. The wax emulsion of claim 1 , wherein the wallboard comprises gypsum.
11. The wax emulsion of claim 5 , wherein the slack wax contains up to 20% oil by weight.
12. The wax emulsion of claim 5 , wherein the wallboard comprises gypsum.