Stereolithography using vinyl ether-epoxide polymers

• US 5,510,226 A
• Filed: 04/20/1994
• Issued: 04/23/1996
• Est. Priority Date: 05/01/1991
• Status: Expired due to Term

• Current Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Original Assignee: Alliedsignal Inc.
• Inventors: Lapin, Stephen C., Sitzmann, Eugene V., Snyder, James R.
• Primary Examiner(s): CHAPMAN, MARK A
• Application Number:
  US08/230,444
• Time in Patent Office: 734 Days
• Field of Search: 430/269, 430/280, 522/170
• US Class Current: 430/269
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing
• CPC Class Codes: C08G 59/18 Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
• CPC Class Codes: C08G 59/68 characterised by the catalysts used
• CPC Class Codes: G03F 7/0037 Production of three-dimensional images
• CPC Class Codes: G03F 7/027 Non-macromolecular photopolymerisable compounds having carbon-to-carbon double bonds, e.g. ethylenic compounds G03F7/075 takes precedence
• CPC Class Codes: G03F 7/038 Macromolecular compounds which are rendered insoluble or differentially wettable G03F7/075 takes precedence; macromolecular azides G03F7/012; macromolecular diazonium compounds G03F7/021
• CPC Class Codes: G03F 7/0385 using epoxidised novolak resin

Abstract

Polymer precursor formulations suitable for stereolithography may be prepared from compositions containing vinyl ether functionalized compounds and epoxy functionalized compounds plus an effective amount of a cationic photoinitiator.

Claims

1. In the process for forming a three-dimensional object from a liquid polymer precursor comprising repeatedly exposing the surface of a bath of said precursor to a beam of actinic light to solidify successive layers of said precursor to make a green structure followed by postcuring of said green structure the improvement comprising employing as said liquid polymer precursor the composition consisting essentially of

(a) at least one multifunctional vinyl ether compound;

(b) at least one multifunctional epoxy compound;

(c) an effective amount of a cationic photoinitiator;

said vinyl ether compounds and epoxy compounds both being curable by acids released by said photoinitiator and having proportions of (a), (b), and (c) selected to provide a polymeric structure having suitable green strength with minimal curl distortion when said composition is polymerized by an actinic light source selected from the group consisting of UV and visible light lasers, the proportions of said vinyl ether compounds and epoxides being defined by the formula M=F/E

where

M is the vinyl ether equivalent weight of the composition and between 150 and 800

F is the total weight in grams of the composition, and

E is the number of vinyl ether equivalents in the composition.

2. The process of claim 1 wherein said actinic light is ultraviolet light produced by a helium/cadmium laser.

3. The process of claim 1 wherein said actinic light is ultraviolet light produced by an argon ion laser.

4. The process of claim 1 wherein said actinic light is visible light produced by an argon ion laser.

5. The process of claim 1 wherein said three-dimensional object is postcured.

6. The process of claim 5 wherein said postcuring is provided by heating.

7. The process of claim 1 wherein M is between 250 and 450.

8. The process of claim 1 wherein the viscosity of said polymer precursor composition is between 50 and 50000 mPa.s.

9. The process of claim 8 wherein the viscosity of said polymer precursor composition is between 50 and 5000 mPa.s.

10. The process of claim 1 wherein said vinyl ether compounds have a functionality of 2 or more.

11. The process of claim 1 wherein said epoxy compounds have a functionality of 2 or more.

12. The process of claim 1 wherein said vinyl ether compounds are derived from at least one member of the group consisting of urethanes, phenols, esters, ethers, siloxanes, and aliphatic or aromatic hydrocarbons.

13. The process of claim 12 wherein at least one vinyl ether has the formula ##STR10## wherein x is 2 or 4

y is 2 or 3.

14. The process of claim 12 wherein at least one vinyl ether has the formula ##STR11## where y is 2.

15. The process of claim 12 wherein at least one vinyl ether has the formula ##STR12## where x is 2, 3, or 4

y is 2 or 4.

16. The process of claim 12 wherein at least one vinyl ether compound has the formula ##STR13## where x is 2, 3, or 4.

17. The process of claim 12 wherein at least one vinyl ether compound has the formula ##STR14##

18. The process of claim 12 wherein at least one vinyl ether compound has the formula

19. The process of claim 12 wherein at least one vinyl ether compound has the formula ##STR15## where x is 2, 3, or 4.

20. The process of claim 12 wherein at least one vinyl ether compound has the formula

21. The process of claim 12 wherein at least one vinyl ether compound has the formula ##STR16##

22. The process of claim 12 wherein at least one vinyl ether compound has the formula ##STR17## where R is H or CH₃.

23. The process of claim 1 wherein said epoxy compounds are derived from at least one member of the group consisting of phenols, novolacs, aliphatic or cycloaliphatic polyols, and polyether polyols.

24. The process of claim 23 wherein said epoxide is a glycidyl ether of bisphenol A.

25. The process of claim 1 wherein said cationic photoinitiator is an onium salt of Group V, VI, and VII elements.

26. The process of claim 25 wherein said cationic photoinitiator is based on an iodonium or sulfonium salt.

27. The process of claim 26 wherein said cationic photoinitiator is a triaryl sulfonium salt of hexafluorophosphate or hexafluoroantimony.

28. The process of claim 26 wherein said cationic photoinitiator is ##STR18## and y is 1 to 18.

29. The process of claim 26 wherein said photoinitiator is ##STR19## and y is 1 to 18.

30. The process of claim 26 wherein said photoinitiator is at least one member of the group consisting of ##STR20##

31. The process of claims 28, 29, or 30 wherein X^- is hexafluorophosphate or hexafluoroantimony.

32. The process of claim 26 wherein the photoinitiator is activated by a photosensitizer.

33. The process of claim 26 wherein at least one vinyl ether has the formula ##STR21##