Surface-treatment method for rapid-manufactured three-dimensional objects

• US 8,765,045 B2
• Filed: 01/12/2007
• Issued: 07/01/2014
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Stratasys Incorporated
• Original Assignee: Stratasys Incorporated
• Inventors: Zinniel, Robert L.
• Primary Examiner(s): Gupta, Yogendra
• Assistant Examiner(s): HINDENLANG, ALISON L
• Application Number:
  US11/652,876
• Publication Number:
  US 20080169585A1
• Time in Patent Office: 2,727 Days
• Field of Search: 264/82, 264/83, 264/341
• US Class Current: 264/341
• CPC Class Codes: B29C 2071/0045 Washing using non-reactive liquids
• 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: B29C 64/35 Cleaning
• CPC Class Codes: B29C 71/0009 using liquids, e.g. solvents, swelling agents spectacle cases, e.g. for cleaning contact lenses A45C11/04; disinfecting or sterilising contact lenses A61L12/00, using liquid substances A61L2/20; cleaning involving the use of liquid in general B08B3/00; for hydrating contact lenses B29D11/00067
• CPC Class Codes: B29K 2995/0073 smooth
• CPC Class Codes: B33Y 40/20 Post-treatment, e.g. curing, coating or polishing

Abstract

A method for forming a surface-treated, three-dimensional object, comprising: solvent smoothing an exterior surface of a rapid-manufactured, three-dimensional object, and media blasting at least a portion of the solvent-smoothed exterior surface.

Claims

1. A method for forming a surface-treated, three-dimensional object, the method comprising:

placing a rapid-manufactured, three-dimensional object in a vapor smoothing chamber, the rapid-manufactured, three-dimensional object compositionally comprising a thermoplastic material, and having an exterior surface that includes surface effects due to a layer-by-layer, rapid manufacturing technique;

vapor smoothing the exterior surface of the rapid-manufactured, three-dimensional object with a solvent vapor in the vapor smoothing chamber to reduce or eliminate the surface effects;

monitoring a specular diffusivity of the exterior surface;

discontinuing the vapor smoothing step when the specular diffusivity of the exterior surface reaches a first predetermined level, wherein the resulting smoothed three-dimensional object has a solvent-smoothed exterior surface with a higher glossiness than the exterior surface prior to the vapor smoothing step;

media blasting at least a portion of the solvent-smoothed exterior surface to provide a burnished exterior surface;

monitoring a specular diffusivity of the solvent-smoothed exterior surface; and

discontinuing the media blasting when the specular diffusivity of the solvent-smoothed exterior surface reaches a second predetermined level, wherein the burnished exterior surface has a lower glossiness than the solvent-smoothed exterior surface prior to the media blasting step.

2. The method of claim 1, wherein the vapor smoothing step reduces a porosity of the three-dimensional object at the exterior surface.

3. The method of claim 1, wherein the solvent vapor uses a solvent selected from the group consisting of methylene chloride, n-propyl bromide, perchloroethylene, trichloroethylene, acetone, methyl ethyl ketone, dimethylacetamide, xylene, toluene, water, alcohols, and combinations thereof.

4. The method of claim 1, further comprising cooling the rapid-manufactured, three-dimensional object below room temperature prior to smoothing the exterior surface.

5. The method of claim 1, wherein placing the rapid-manufactured, three-dimensional objet in the vapor smoothing chamber comprises suspending the rapid-manufactured, three-dimensional object from a hook-like member in the vapor smoothing chamber.

6. The method of claim 1, further comprising abrasively removing at least one surface blemish from the solvent-smoothed exterior surface.

7. The method of claim 1, wherein the media blasting comprises blasting with sodium bicarbonate.

8. A method for forming a surface-treated, three-dimensional object, the method comprising:

building at least a portion of a three-dimensional object from a thermoplastic material with a layer-by-layer, rapid manufacturing technique, the three-dimensional object having an exterior surface that includes surface effects due to the layer-by-layer, rapid manufacturing technique;

placing the built three-dimensional object in a vapor smoothing chamber;

vapor smoothing the exterior surface with a solvent-based vapor smoothing process in the vapor smoothing chamber to reduce or eliminate the surface effects;

monitoring a specular diffusivity of the exterior surface;

discontinuing the vapor smoothing process when the specular diffusivity of the exterior surface reaches a first predetermined level, wherein the resulting smoothed three-dimensional object has a solvent-smoothed exterior surface with a higher glossiness than the exterior surface prior to the vapor smoothing step;

placing the smoothed three-dimensional object in a media blasting system;

media blasting at least a portion of the solvent-smoothed exterior surface while the smoothed three-dimensional object is disposed in the media blasting system;

monitoring a specular diffusivity of the solvent-smoothed exterior surface; and

discontinuing the media blasting when the specular diffusivity of the smoothed exterior surface reaches a second predetermined level, wherein the burnished exterior surface has a lower glossiness than the solvent-smoothed exterior surface prior to the media blasting step.

9. The method of claim 8, wherein the vapor smoothing step reduces a porosity of the three-dimensional object at the exterior surface.

10. The method of claim 8, further comprising cooling the built three-dimensional object below room temperature prior to vapor smoothing the exterior surface.

11. The method of claim 8, wherein the media blasting comprises blasting with sodium bicarbonate.

12. A method for forming a surface-treated, three-dimensional object, the method comprising:

providing a three-dimensional object at least partially built with a layer-by-layer, rapid manufacturing technique using a thermoplastic material, the three-dimensional object having an exterior surface that includes surface effects due to the layer-by-layer, rapid manufacturing technique;

placing the three-dimensional object in a vapor smoothing chamber;

reducing or eliminating the surface effects of the exterior surface with a solvent-based, vapor smoothing process in the vapor smoothing chamber to provide a solvent-smoothed exterior surface having a higher glossiness than the exterior surface prior to the solvent-based, vapor smoothing process;

monitoring a specular diffusivity of the exterior surface during the solvent-based, vapor smoothing process;

discontinuing the vapor smoothing process when the specular diffusivity of the exterior surface reaches a first predetermined level, wherein the resulting smoothed three-dimensional object has a solvent-smoothed exterior surface with a higher glossiness than the exterior surface prior to the vapor smoothing step;

media blasting at least a portion of the solvent-smoothed exterior surface;

monitoring a specular diffusivity of the solvent-smoothed exterior surface during the media blasting step; and

discontinuing the media blasting when the specular diffusivity of the solvent-smoothed exterior surface reaches a second predetermined level, wherein the burnished exterior surface has a lower glossiness than the solvent-smoothed exterior surface prior to the media blasting step.

13. The method of claim 12, wherein the solvent-based vapor smoothing process uses a solvent selected from the group consisting of methylene chloride, n-propyl bromide, perchloroethylene, trichloroethylene, acetone, methyl ethyl ketone, dimethylacetamide, xylene, toluene, water, alcohols, and combinations thereof.

14. The method of claim 12, further comprising cooling the rapid-manufactured, three-dimensional object below room temperature prior to the vapor smoothing process.

15. The method of claim 12, wherein the media blasting comprises blasting with sodium bicarbonate.

16. The method of claim 12, wherein providing the three-dimensional object that is at least partially built with the rapid manufacturing technique comprises building the three-dimensional object in a layer-by-layer manner using the rapid manufacturing technique.

17. The method of claim 12, wherein the surface effects of the exterior surface comprise stair-step effects.