Catalyst and composition for silicone dental impression materials

• US 5,998,561 A
• Filed: 02/17/1998
• Issued: 12/07/1999
• Est. Priority Date: 03/11/1997
• Status: Expired due to Fees

• Current Assignee: Jeneric/Pentron Incorporated (Danaher Corporation)
• Original Assignee: Jeneric/Pentron Incorporated (Danaher Corporation)
• Inventors: Jada, Sivananda S.
• Primary Examiner(s): Moore, Margaret G.
• Application Number:
  US09/024,180
• Time in Patent Office: 658 Days
• Field of Search: 523/109, 528/15
• US Class Current: 528/15
• CPC Class Codes: A61K 6/90 Compositions for taking dental impressions
• CPC Class Codes: C08G 77/12 containing silicon bound to hydrogen C08G77/045 takes precedence
• CPC Class Codes: C08G 77/20 containing silicon bound to unsaturated aliphatic groups C08G77/045 takes precedence
• CPC Class Codes: C08L 2666/52 Metal-containing compounds
• CPC Class Codes: C08L 83/00 Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 83/04 Polysiloxanes

Abstract

A curable silicone dental impression composition is presented, preferably comprising a polyorganohydrogensiloxane having at least one silicon-bonded hydrogen atom; a silicone polymer having at least alkenyl groups; a vinyl siloxane/platinum/palladium catalyst complex; and inorganic fillers and other additives known in the art. The catalyst in accordance with the present invention is a complex of 1,3-divinyltetramethyldisiloxane and hexachloroplatinic acid doped with palladium, and prevents outgassing of hydrogen. The final catalyst complex has a platinum content in the range from about 1.1%-1.2% platinum and 500-600 ppm palladium.

Claims

1. A room temperature curable dental silicone composition for the manufacture of a dental impression material comprising a mixture of

(a) a polyorganohydrogensiloxane having at least one silicone-bonded hydrogen atom;

(b) a silicone polymer having at least two alkenyl groups; and

(c) an unsaturated aliphatic silane/platinum/palladium catalyst complex or an unsaturated aliphatic siloxane/platinum/palladium catalyst complex.

2. The room curable composition in accordance with claim 1, wherein

the catalyst complex is formed by the complexation of a hexachloroplatinic acid preparation doped with palladium with a silane or siloxane having at least two aliphatic dienes.

3. The room curable composition of claim 2, wherein

the complexation is with 1,3-divinyltetramethyldisiloxane.

4. The room curable composition in accordance with claim 2, wherein

the hexachloroplatinic acid preparation comprises from about 30% to about 50% by weight platinum and from about 0.0001% to about 75% by weight palladium.

5. The room curable composition in accordance with claim 2, wherein

the hexachloroplatinic acid preparation comprises from about 4% to about 20% by weight palladium.

6. The room curable composition in accordance with claim 2, wherein

the hexachloroplatinic acid preparation comprises from about 35% to about 39% by weight platinum and from about 4% to about 15% by weight palladium.

7. The room curable composition in accordance with claim 1, wherein

the catalyst complex comprises from about 0.5% to about 4% by weight platinum and from about 250 to about 1000 ppm by weight palladium.

8. The room curable composition in accordance with claim 1, wherein

the catalyst complex comprises from about 0.9% to about 4% by weight platinum and from about 400-600 ppm by weight palladium.

9. A cured dental silicone composition, formed by curing a mixture of

(a) a polyorganohydrogensiloxane having at least one silicon-bonded hydrogen atom;

(b) a silicone polymer having at least two alkenyl groups; and

(c) an unsaturated aliphatic silane/platinum/palladium catalyst complex or an unsaturated aliphatic siloxane/platinum/palladium catalyst complex.

10. The room curable composition in accordance with claim 9, wherein

the catalyst complex is formed by the complexation of a hexachloroplatinic acid preparation doped with palladium with a silane or siloxane having at least two unsaturated groups.

11. The room curable composition in accordance with claim 10, wherein

the complexation is with 1,3-divinyltetramethyldisiloxane.

12. The room curable composition in accordance with claim 10, wherein

the hexachloroplatinic acid preparation comprises from about 30% to about 50% by weight platinum and from about 0.0001% to about 75% by weight palladium.

13. The room curable composition in accordance with claim 10, wherein

the hexachloroplatinic acid preparation comprises from about 4% to about 20% by weight palladium.

14. The room curable composition in accordance with claim 10, wherein

the hexachloroplatinic acid preparation comprises from about 35% to about 39% by weight platinum and from about 4% to about 15% by weight palladium.

15. The room curable composition in accordance with claim 9, wherein

the catalyst complex comprises from about 0. 5% to about 4% by weight platinum and from about 250 to about 1000 ppm by weight palladium.

16. The room curable composition in accordance with claim 9, wherein

the catalyst complex comprises from about 0.9% to about 4% by weight platinum and from about 500-600 ppm by weight palladium.

17. The cured composition in accordance with claim 9, in the form of a dental impression comprising a negative mold of oral tissue.

18. A method of making a dental silicone impression, comprising making a negative mold of oral tissue, using as said mold a curable silicone composition comprising a mixture of

(a) a polyorganohydrogensiloxane having at least one silicon-bonded hydrogen atom;

(b) a silicone polymer having at least two alkenyl groups; and

(c) an unsaturated aliphatic silane/platinum/palladium catalyst complex or an unsaturated aliphatic siloxane/platinum/palladium catalyst complex.

19. The room curable composition in accordance with claim 18, wherein

the catalyst complex is formed by the complexation of a hexachloroplatinic acid preparation doped with palladium with a silane or siloxane having at least two unsaturated groups.

20. The room curable composition in accordance with claim 19, wherein

the complexation is with 1,3-divinyltetramethyldisiloxane.

21. The room curable composition in accordance with claim 19, wherein

the hexachloroplatinic acid preparation comprises from about 30% to about 50% by weight platinum and from about 0.0001% to about 75% by weight palladium.

22. The room curable composition in accordance with claim 19, wherein

the hexachloroplatinic acid preparation comprises from about 4% to about 20% by weight palladium.

23. The room curable composition in accordance with claim 19, wherein

the hexachloroplatinic acid preparation comprises from about 35% to about 39% by weight platinum and from about 4% to about 15% by weight palladium.

24. The room curable composition in accordance with claim 18, wherein

the catalyst complex comprises from about 0.5% to about 4% by weight platinum and from about 250 to about 1000 ppm by weight palladium.

25. The room curable composition in accordance with claim 18, wherein

the catalyst complex comprises from about 0.9% to about 4% by weight platinum and from about 500-600 ppm by weight palladium.