Aqueous release agent and its use in the production of polyurethane moldings

1. An aqueous dispersion comprising substantially water, agents having release activity, and emulsifiers, wherein said agents comprise at least a combination of

A) at least one agent having a release activity, selected from the group consisting of soaps, oils, waxes and silicones, and

B) polyisobutylene in an amount of 0.1 to 15% by weight based on the total weight of the aqueous dispersion.

2. The aqueous dispersion as claimed in claim 1 wherein said at least one agent having a release activity is present in an amount of 0.5 to 40% by weight based on the total weight of the aqueous dispersion.

3. The aqueous dispersion as claimed in claim 2 , further comprising

C) from 0.1 to 10% by weight of said emulsifiers,

D) from 0.1 to 5% by weight of catalysts,

E) from 0.1 to 5% by weight of foam stabilizers,

F) from 0.1 to 5% by weight of viscosity modifiers,

G) from 0.1 to 2% by weight of customary preservatives, bactericides, fungicides and antioxidants, and

H) said water to 100% by weight.

4. The aqueous dispersion as claimed in claim 1 , wherein the agents A) having a release activity have an average molar mass greater than 200.

5. The aqueous dispersion as claimed in claim 1 , wherein said agents A) having a release activity include at least one compound selected from the group consisting of liquid, solid, natural or synthetic waxes, oils, esters of carboxylic acids with alcohols or fatty alcohols, metal soaps and silicones.

6. The aqueous dispersion as claimed in claim 1 , wherein the polyisobutylene has a molar mass of from 200 to 3000.

7. The aqueous dispersion as claimed in claim 1 , wherein said emulsifier is selected from the group consisting of anionic, cationic, zwitterionic and nonionic surfactants.

8. A method for producing a polyurethane molding comprising adding an aqueous dispersion of claim 1 to surfaces of a mold prior to adding a reactive polyurethane system to said mold.

9. The method as claimed in claim 8 , wherein said mold is heated prior to adding the aqueous dispersion to said mold.

10. The method as claimed in claim 9 , wherein said mold is heated to a temperature from 45° to 80° C.

11. The method as claimed in claim 8 , wherein said aqueous dispersion comprises:

from 0.5 to 40% by weight of said at least one agent having release activity, selected from the group consisting of soaps, oils, waxes and silicones, and

from 0.1 to 15% by weight of said polyisobutylene.

12. The method as claimed in claim 11 wherein said aqueous dispersion, further comprises

C) from 0.1 to 10% by weight of said emulsifiers,

D) from 0.1 to 5% by weight of catalysts,

E) from 0.1 to 5% by weight of foam stabilizers,

F) from 0.1 to 5% by weight of viscosity modifiers,

G) from 0.1 to 2% by weight of customary preservatives, bactericides, fungicides and antioxidants, and

H) said water to 100% by weight.

13. The method as claimed in claim 8 , wherein the agents A) having a release activity have an average molar mass greater than 200.

14. The method as claimed in claim 8 , wherein the agents A) having a release activity are selected from at least one compound selected from the group consisting of liquid, solid, natural or synthetic waxes, oils, esters of carboxylic acids with alcohols or fatty alcohols, metal soaps and silicones is concomitantly used as agents A) having a release activity.

15. The method as claimed in claim 8 , wherein the polyisobutylene has a molar mass of from 200 to 3000.

16. The method as claimed in claim 8 , wherein the emulsifier is selected from the group consisting of anionic, cationic, zwitterionic and nonionic surfactants.

17. An aqueous dispersion comprising substantially water, agents having release activity, and emulsifiers, wherein said agents comprise at least a combination of

A) at least one agent having a release activity, selected from the group consisting of soaps, oils, waxes and silicones, and

B) liquid polyisobutylene having a molar mass of from 200 to 3000.