POLYMERS OF ORGANICALLY MODIFIED SILOXANE RESINS WITH RELEASE EFFECT

Abstract

The present invention relates to compositions for producing release-effect coatings, to a process for preparing the compositions, and to substrates coated with them.

Description

Claims

1. A composition for producing release coatings, comprising (A) 100 parts by weight of one or more polysiloxane resins of the general formula RaSi(OR′)bO(4-a-b)/2 where 0<a<2, 0<b<2, and a+b<4,(B) 0.05 to 10 parts by weight of one or more linear and/or branched polysiloxanes of the formula R″O—[R′″2Si—O]n—R″and(C) 5 to 80 parts by weight of a hydroxyl-containing polyester,whereRa, R′, R″, and R′″ each independently of one another are an alkyl radical having 1 to 8 carbon atoms or an aromatic radical having 6 to 20 carbon atoms, andn is a number in the range from 4 to 5000,wherein(D) 2 to 80 parts by weight of one or more nanoscale solids.

2. The composition as claimed in claim 1, wherein the radicals Ra, R′, R″, and R′″ each independently of one another are a radical selected from methyl, ethyl, isopropyl, n-butyl, tert-butyl, and phenyl.

3. The composition as claimed in claim 1, wherein the radical R″ is a hydrogen radical or a —Si(CH3)3 group.

4. The composition as claimed in claim 1, wherein the radical R′″ is a polysiloxane side chain of the general formula —[R′″2Si—O]n—R″.

5. The composition as claimed in claim 1, containing 0.5 to 8 parts by weight of polysiloxane (B), based on 100 parts by weight of (A).

6. The composition as claimed in claim 1, containing 30 to 70 parts by weight of polyester (C), based on 100 parts by weight of (A).

7. The composition as claimed in claim 1, containing 15 to 40 parts by weight of a nanoscale solid (D), based on 100 parts by weight of (A)+(B)+(C).

8. The composition as claimed in claim 1, further comprising an esterification catalyst.

9. The composition as claimed in claim 1, further comprising pigments, rheology control agents, fillers, solvents, additives, adhesion promoters and/or stabilizers.

10. The composition as claimed in claim 1, which is obtained by simultaneously reacting components (A), (B), (C), and (D).

11. The composition as claimed in claim 10, wherein the degree of conversion is 20% to 80%.

12. A substrate coated with a composition as claimed in claim 1.

13. A process for preparing a composition as claimed in claim 1, which comprises reacting components (A), (B), (C), and (D) in the presence of a catalyst.

14. A process for preparing a composition as claimed in claim 1, which comprises preparing components (A), (B), (C), and (D) using a high-pressure homogenizer.

15. The process as claimed in claim 13, wherein the catalyst is an organotitanium catalyst.

16. The process as claimed in claim 15, wherein components (A), (B), (C), and (D) are reacted in the presence of one or more solvents.

17. The process as claimed in claim 16, wherein the reaction is carried out to a degree of conversion of 20% to 80%, based on component (B).

18. The composition of claim 2, wherein: the radical R″ is a hydrogen radical or a —Si(CH3)3 group; andthe radical R′″ is a polysiloxane side chain of the general formula —[R′″2Si—O]n—R″.

19. The composition of claim 19, containing 0.5 to 8 parts by weight of polysiloxane (B), based on 100 parts by weight of (A);containing 30 to 70 parts by weight of polyester (C), based on 100 parts by weight of (A); andcontaining 15 to 40 parts by weight of a nanoscale solid (D), based on 100 parts by weight of (A)+(B)+(C).

20. The composition of claim 11, wherein the degree of conversion is 40% to 65%.