Viscosity stabilization of radiation-curable filled compositions

• US 6,350,403 B1
• Filed: 05/31/2000
• Issued: 02/26/2002
• Est. Priority Date: 07/21/1997
• Status: Expired due to Term

• Current Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Original Assignee: Vantico Inc. (Huntsman Corporation)
• Inventors: Hanna, Stephen D., Melisaris, Anastasios P., Pang, Thomas H.
• Primary Examiner(s): Seidleck, James J.
• Assistant Examiner(s): McClendon, Sanza L.
• Application Number:
  US09/584,444
• Time in Patent Office: 636 Days
• Field of Search: 522/100, 522/102, 522/103, 522/168, 522/170, 522/173, 522/178, 522/182, 522/71, 522/74, 522/75, 522/78, 522/79, 522/83, 430/269, 430/280.1, 430/281.1, 264/401
• US Class Current: 264/401
• CPC Class Codes: B29C 64/135 the energy source being concentrated, e.g. scanning lasers or focused light sources
• CPC Class Codes: B29K 2105/0094 having particular viscosity
• CPC Class Codes: B29K 2105/16 Fillers
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 70/10 Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
• CPC Class Codes: C08K 5/17 Amines; Quaternary ammonium compounds
• CPC Class Codes: G03F 7/0037 Production of three-dimensional images

Abstract

The present invention relates to a process for the production of three-dimensional articles by stereolithography using a radiation-curable composition comprising a mixture of at least one cationically polymerizable compound and/or at least one free radical polymerizable compound, at least one filler material and at least one photoinitiator for cationic and/or radical polymerization. An organic viscosity stabilizer material may be brought into contact with the composition to substantially delay or prevent undesirable viscosity increase and subsequently premature polymerization. A filler material is optionally added to the composition in an effective amount to at least delay or prevent a significant increase in viscosity and polymerization. The process is particularly suitable for stabilizing resins in stereolithography baths. The present invention also relates to a cured articles resulting from said process and a process for manufacturing said radiation-curable compositions and stabilized compositions resulting therefrom.

Claims

1. A cured three-dimensional article that has been produced by stereolithocradhy and obtained by subjecting a radiation-curable composition to actinic radiation, said composition comprising a mixture of at least one cationically polymerizable compound and/or at least one radical polymerizable compound, at least one filler material, and at least one photoinitiator for caionic and/or radical polymerizations, in which an organic base stabilizer material is brought into contact with said composition in an effective amount to delay or prevent a significant increase in viscosity of the overall composition.

20. A cured three-dimensional article according to claim 1 wherein the organic base stabilizer material is a benzyl-N,N-dialkylamine.

21. A cured three-dimensional article according to claim 20 wherein the benzyl-N,N′

-dialkylamine is present at a concentration of 5 to 5000 ppm in the overall composition.

22. A cured three-dimensional article according to claim 20 wherein the benzyl-N,N′

-dialkylamine is benzyl-N,N′

-dimethylamine.

23. A cured three-dimensional article according to claim 1 wherein the material has at least in part been surface treated with a compound-coupling agent that is either unreactive or capable of reacting when exposed to actinic radiation or free radicals.

24. A cured three-dimensional article according to claim 1 wherein the cationically polymerizable compound contains at least one of a 1,2-epoxide, a vinyl ether, lactone, acetal, cyclic sulfide, cyclic ether or siloxane group.

25. A cured three-dimensional article according to claim 1 wherein the filler material has a surface which has been treated such that it may undergo reaction with at least one other compound in the mixture.

26. A cured three-dimensional article according to claim 1 wherein the surface of said at least one filler material has been treated with beta-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane or methyltriethoxysilane.

2. A process for manufacturing a stabilized filled resin composition for stereolithography comprising combining a mixture of at least one cationically polymerizable compound and/or at least one radical polymerizable compound, at least one filler material, at least one photoinitiator for cationic and/or radical polymerization(s) and an organic base stabilizer material in an effective amount to delay or prevent a significant increase in viscosity, in a reaction vessel.

27. A process for manufacturing a stabilized filled resin composition according to claim 2 wherein the organic base stabilizer material is benzyl-N,N′

-dialkylamine.

28. A process for manufacturing a stabilized filled resin composition according to claim 27 wherein the benzyl-N,N′

-dialkylamine is present at a concentration of 5 to 5000 ppm in the overall composition.

29. A process for manufacturing a stabilized filled resin composition according to claim 27 wherein the benzy-N,N′

-dialkylamine is benzyl-N,N′

-dimethylamine.

30. A process for manufacturing a stabilized filled resin composition according to claim 2 wherein the filler material has at least in part been surface treated with a compound-coupling agent that is either unreactive or capable of reacting when exposed to actinic radiation or free radicals.

3. A stabilized radiation-curable composition comprising a mixture of at least one radiation polymerizable compound, at least one filler material, at least one photoinitiator for polymerization and an organic viscosity stabilizer material selected from the group consisting of aryl-N,N′

-dialkylamines and benzyl-N,N-dialkylamines in an effective amount to delay or prevent a significant increase in viscosity of the overall composition.

5. A stabilized radiation-curable composition according to claim 3 wherein the organic viscosity stabilizer material is a benzyl-N,N′

-dialkylamine.

6. A stabilized radiation-curable composition according to claim 5 wherein the benzyl-N,N′

-dialkylamine is present at a concentration of 5 to 5000 ppm in the overall composition.

7. A stabilized radiation-curable composition according to claim 5 wherein the benzyl-N,N′

-dialkylamine is benzyl-N,N-dimethylamine.

8. A stabilized radiation curable composition according to claim 3 wherein the at least one radiation polymerizable compound comprises a cationically polymerizable compound.

9. A stabilized radiation curable composition according to claim 3 wherein the at least one radiation polymerizable compound comprises a free radical polymerizable compound.

10. A stabilized radiation curable composition according to claim 8 wherein the cationically polymerizable compound contains at least one of a 1,2-epoxide, a vinyl ether, lactone, acetal, cyclic sulfide, cyclic ether, or siloxane group.

11. A stabilized radiation curable composition according to claim 3 wherein the inorganic filler material has at least in part been surface-treated with a compound-coupling agent that is either unreactive or capable of reacting when exposed to actinic radiation or free radicals.

31. A process for manufacturing a stabilized filled resin composition according to claim 3 wherein the cationically polymerizable compound contains at least one of a 1,2-epoxide, a vinyl ether, lactone, acetal, cyclic sulfide, cyclic ether or siloxane group.

32. A process for manufacturing a stabilized filled resin composition according to claim 3 wherein the filler material has a surface which has been treated such that it may undergo reaction with at least one other compound in the mixture.

33. A process for manufacturing a stabilized filled resin composition according to claim 3 wherein the surface of said filler material has been treated with beta-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane or methyltriethoxysilane.

4. A stabilized radiation-curable composition comprising a mixture of at least one radiation polymerizable compound, at least one filler material selected from the group consisting of sodium silicate, potassium silicate, calcium silicate, aluminum silicate, aluminum oxide and alumina trihydrate in an amount effective to delay or prevent a significant viscosity increase of the overall composition and at least one photoinitiator for polymerization.

12. A stabilized radiation curable composition according to claim 4 wherein the at least one radiation polymerizable compound comprises a cationically polymerizable compound.

13. A stabilized radiation curable composition according to claim 4 wherein the at least one radiation polymerizable compound comprises a free radical polymerizable compound.

14. A stabilized radiation curable composition according to claim 12 wherein the cationically polymerizable compound contains at least one of a 1,2-epoxide, a vinyl ether, lactone, acetal, cyclic sulfide, cyclic ether or siloxane group.

15. A stabilized radiation curable composition according to claim 4 wherein the filler material has a surface which has been treated such that it may undergo reaction with at least one other compound in the mixture.

16. A stabilized radiation curable composition comprising a mixture of at least one radiation polymerizable compound, at least one inorganic filler which has been surface treated such that that the surface treatment improves the compositional viscosity stability as compared to said mixture with the exception that the filler material has not been surface treated, and at least one photoinitiator for polymerization.

17. A stabilized radiation curable composition according to claim 16 wherein the at least one radiation polymerizable compound comprises a cationically polymerizable compound.

18. A stabilized radiation curable composition according to claim 16 wherein the surface of said inorganic filler has been treated with beta-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane or methyltriethoxysilane.

19. A stabilized radiation curable composition according to claim 16 wherein the at least one radiation polymerizable compound comprises a free radical polymerizable compound.