Production of three-dimensional objects

• US 5,514,519 A
• Filed: 04/07/1994
• Issued: 05/07/1996
• Est. Priority Date: 10/02/1991
• Status: Expired due to Term

• Current Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Original Assignee: Spectra Group Limited, Inc. (Formlabs Incorporated)
• Inventors: Neckers, Douglas C.
• Primary Examiner(s): CHAPMAN, MARK A
• Application Number:
  US08/224,503
• Time in Patent Office: 761 Days
• Field of Search: 430/269, 430/292, 430/138, 430/270, 430/281, 264/22
• US Class Current: 430/269
• CPC Class Codes: B29C 35/08 by wave energy or particle radiation B29C64/00, B29C71/04 take precedence
• CPC Class Codes: B29C 41/003 characterised by the choice of material
• CPC Class Codes: B29C 64/135 the energy source being concentrated, e.g. scanning lasers or focused light sources
• CPC Class Codes: B29C 64/188 involving additional operations performed on the added layers, e.g. smoothing, grinding or thickness control surface shaping B29C59/00; after-treatment of articles without altering their shape B29C71/00
• CPC Class Codes: B29K 2105/0032 Pigments, colouring agents or opacifiyng agents
• CPC Class Codes: B29K 2995/002 Coloured
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G03F 7/0037 Production of three-dimensional images
• CPC Class Codes: G03F 7/105 having substances, e.g. indicators, for forming visible images

Abstract

A method for producing a three-dimensional object having selected elements which are colored a different color than the color of other elements of the object, comprising the steps of:

a. providing a film of a photohardenable composition containing a photoresponsive agent,

b. irradiating the film in a cross-sectional pattern of the object to be formed so as to form hardened areas in the film.

c. selectively irradiating one or more portions of the cross-sectional pattern corresponding to the selected elements which are desired to be colored a different color than the color of other elements of the object with radiation which activates the photoresponsive agent, the photoresponsive agent thereby producing color in or removing color from the selectively irradiated portions of the cross-sectional pattern, the steps being performed with radiation of a different wavelength than the radiation used in performing step b,

d. repeating steps a, b and c to form successive adjacent cross-sectional patterns of the object, and

e. integrating the cross-sectional patterns to provide the three-dimensional object.

Claims

1. A method for producing a three-dimensional object having selected elements which are colored a different color than the color of other elements of said object, comprising the steps of:

a. providing a film of a photohardenable composition containing a photoresponsive agent,

b. irradiating said film in a cross-sectional pattern of the object to be formed so as to form hardened areas in said film.

c. selectively irradiating one or more portions of said cross-sectional pattern corresponding to said selected elements which are desired to be colored said different color than the color of other elements of the object with radiation which activates said photoresponsive agent, said photoresponsive agent thereby producing color in or removing color from said selectively irradiated portions of said cross-sectional pattern, said steps being performed with radiation of a different wavelength than the radiation used in performing step b,

d. repeating said steps a, b and c to form successive adjacent cross-sectional patterns of said object, and

e. integrating said cross-sectional patterns to provide said object.

2. The method of claim 1 wherein said three-dimensional object is prepared by stereolithography.

3. The method of claim 1 wherein said irradiation is accomplished using at least one laser.

4. The method of claim 1 wherein said photoresponsive agent is a photochromic compound.

5. The method of claim 4 wherein said photochromic compound is a benzospiropyran.

6. The method of claim 5 wherein said photochromic compound is 1,3-dihydro-6'"'"',8'"'"'-dichloro-1-hexyl-3,3-dimethyl spiro 2H-indole-2,2'"'"'- 3H!benzopyran!.

7. The method of claim 5 wherein said photochromic compound is 1,3-dihydro-6'"'"'-nitro-8'"'"'-bromo-1-hexyl,3,3-dimethyl spiro 2H-indole-2,2'"'"'- 3H!benzopyran!.

8. The method of claim 1 wherein said photoresponsive agent comprises a photosensitive acid generator or photosensitive base generator.

9. The method of claim 8 wherein said photoresponsive agent is methyl red or bromothymol blue and 2-nitrobenzaldehyde.

10. The method of claim 1 wherein said photoresponsive agent is a photobleachable dye.

11. The method of claim 1 wherein said photohardenable composition contains a plurality of photoresponsive agents, each agent controlling the formation of a different color such that selected portions of said objects may be colored differently.

12. The method of claim 1 wherein said step c is performed after said step b.

13. The method of claim 1 wherein said step c is performed simultaneously with step b.

14. The method of claim 13 wherein said photoresponsive agent is a photobleachable photoinitiator.