US5234636A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods of coating stereolithographic parts
Assignee: 3D Systems Inc
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Filing: 1992-08-13
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Granted: 1993-08-10
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Expires: 2012-08-13
Abstract
Abstract Methods of coating stereolithographic parts and smoothing over characteristic surface discontinuities having alternating recesses and peaks. A stereolithographic part is first substantially covered with a substance capable of becoming less viscous when heated at a temperature which does not substantially thermally degrade the part, wherein the heated substance has an appropriate surface tension. Then, the substance is heated to that temperature until the substance flows preferentially into the recesses of the surface discontinuities and away from the peaked surface discontinuities. The substance will thereafter form a short surface connection over the recesses of the discontinuities through the surface tension of the heated substance. The substance is then polymerized or hardened either by cooling, thermally setting or by UV curing.
Inventors
- 👤 Charles W. Hull
- 👤 Richard N. Leyden
- 👤 Marek Sekowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:02
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/0037; B; B05; B05D; B05D1/00; B05D1/02; B05D1/04; B05D1/045; B05D5/00; B05D5/06; B05D5/061; B05D7/00; B05D7/02; B29; B29C; B29C33/00; B29C33/38; B29C33/3842; B29C64/00; B29C64/10; B29C64/106; B29C64/124; B29C64/129; B29C64/135; B29C64/30; B33; B33Y; B33Y10/00; B33Y40/00; B33Y40/20; B05D2401/00; B05D2401/30; B05D2401/32; B05D3/00; B05D3/06; B05D3/061; B05D3/065; B05D3/067; B29C64/35; B29K; B29K2995/00; B29K2995/0037; B29K2995/0072; B29K2995/0073; H; H05; H05K; H05K3/00; H05K3/22; H05K3/28
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
175 words
In a stereolithographic method for forming a part from a material capable of selective physical transformation upon exposure to prescribed synergistic stimulation including forming successive cross-sectional patterns of the part on a selected surface of the material capable of selective physical transformation, relatively displacing the selected surface and said cross-sections as they are formed, and building up the part layer by layer in a step-wise fashion, wherein the part has surface discontinuities between at least some adjacent layers, the improvement comprising the following steps: electrostatically coating at least a surface of the part with powder particles which melt at a temperature in the range of about 60-120 degrees Centigrade into a melted powder having an appropriate surface tension; heating the coated part at said temperature until the particles melt into a melted powder, which flows into surface discontinuities, and thereafter forms short surface connections across the surface discontinuities through the surface tension of the melted powder; and solidifying the melted powder to form a permanent coating which becomes a portion of the stereolithographically produced part.
Claim 2
Dependent Claim
175 words
In a stereolithographic method for forming a part from a material capable of selective physical transformation upon exposure to prescribed synergistic stimulation including forming successive cross-sectional patterns of the part on a selected surface of the material capable of selective physical transformation, relatively displacing the selected surface and said cross-sections as they are formed, and building up the part layer by layer in a step-wise fashion, wherein the part has surface discontinuities between at least some adjacent layers, the improvement comprising the following steps: electrostatically coating at least a surface of the part with powder particles which melt at a temperature in the range of about 60-120 degrees Centigrade into a melted powder having an appropriate surface tension; heating the coated part at said temperature until the particles melt into a melted powder, which flows into surface discontinuities, and thereafter forms short surface connections across the surface discontinuities through the surface tension of the melted powder; and solidifying the melted powder to form a permanent coating which becomes a portion of the stereolithographically produced part.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein the powder is a thermoset.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein the powder is a thermoplastic.
Claim 5
Dependent Claim
11 words
The method of claim 1 wherein the powder is an epoxy.
Claim 6
Dependent Claim
11 words
The method of claim 1 wherein the powder is a polyester.
Claim 7
Dependent Claim
12 words
The method of claim 1 wherein the powder is a hybrid epoxy/polyester.
Claim 8
Dependent Claim
20 words
The method of claim 1 wherein the powder particles have a particle diameter of about at least about 50 microns.
Claim 9
Dependent Claim
39 words
The method of claim 1 wherein the powder is a UV curable powder, and the method further comprises the step of irradiating the coated part, at a time after said heating, with UV light until the melted powder cures.
Claim 10
Dependent Claim
40 words
The method of claim 1 wherein the powder is a thermoset which cross-links at a temperature below 120 degrees Centigrade, and wherein the step of solidifying the melted powder further comprises heating the coated part until the melted powder cures.
Claim 11
Independent Claim
152 words
A method for coating a surface of a stereolithographic part having surface discontinuities between at least some adjacent layers, comprising the following steps: applying a liquid, which is curable in response to synergistic stimulation and which is capable of becoming less viscous when heated to a temperature in the range of about 60-120 degrees Centigrade, to substantially coat a surface of the part, the less viscous liquid having an appropriate surface tension; heating the coated part at a temperature in said range until the liquid becomes less viscous, flows into at least a portion of the surface discontinuities, and thereafter forms short surface connections across said at least portion of the surface discontinuities through the surface tension of the liquid; and irradiating the coated part with said synergistic stimulation, at a time after said heating, until the liquid cures to form a permanent coating which becomes a portion of the stereolithographic part.
Claim 12
Independent Claim
152 words
A method for coating a surface of a stereolithographic part having surface discontinuities between at least some adjacent layers, comprising the following steps: applying a liquid, which is curable in response to synergistic stimulation and which is capable of becoming less viscous when heated to a temperature in the range of about 60-120 degrees Centigrade, to substantially coat a surface of the part, the less viscous liquid having an appropriate surface tension; heating the coated part at a temperature in said range until the liquid becomes less viscous, flows into at least a portion of the surface discontinuities, and thereafter forms short surface connections across said at least portion of the surface discontinuities through the surface tension of the liquid; and irradiating the coated part with said synergistic stimulation, at a time after said heating, until the liquid cures to form a permanent coating which becomes a portion of the stereolithographic part.
Claim 13
Dependent Claim
17 words
The method of claim 10, wherein the liquid is applied by dipping the part into the liquid.
Claim 14
Dependent Claim
16 words
The method of claim 10 wherein the liquid is applied by spraying it onto the part.
Claim 15
Dependent Claim
12 words
The method of claim 10 wherein the liquid contains a volatile solvent.
Claim 16
Dependent Claim
44 words
The method of claim 10 wherein the liquid comprises about 10-50% by volume of a photocurable resin, about 45-85% by volume of a volatile solvent, about 1-5% by volume of a photoinitiator and up to about 0.1% by volume of a flow control agent.
Claim 17
Dependent Claim
190 words
An improved stereolithographic method for forming a part from a material capable of selective physical transformation upon exposure to prescribed synergistic stimulation including forming successive cross-sectional patterns of the part on a selected surface of the material capable of selective physical transformation, reactively displacing the selected surface and said cross sections as they are formed and building up the part in a step-wise fashion, wherein the part has surface discontinuities between at least some adjacent layers, the improvement comprising the steps of: applying a substance to at least a portion of the said at least one surface of said part which is capable of becoming less viscous when heated to a temperature which does not substantially thermally degrade the part, wherein the less viscous substance has an appropriate surface tension; and heating the substance up to said temperature until the substance flows into at least some of the surface discontinuities and forms a short surface connection over the discontinuities through the surface tension of the less viscous substance; and solidifying the substance after it forms the short surface connections so that it permanently becomes a portion of the stereolithography part.
Claim 18
Dependent Claim
190 words
An improved stereolithographic method for forming a part from a material capable of selective physical transformation upon exposure to prescribed synergistic stimulation including forming successive cross-sectional patterns of the part on a selected surface of the material capable of selective physical transformation, reactively displacing the selected surface and said cross sections as they are formed and building up the part in a step-wise fashion, wherein the part has surface discontinuities between at least some adjacent layers, the improvement comprising the steps of: applying a substance to at least a portion of the said at least one surface of said part which is capable of becoming less viscous when heated to a temperature which does not substantially thermally degrade the part, wherein the less viscous substance has an appropriate surface tension; and heating the substance up to said temperature until the substance flows into at least some of the surface discontinuities and forms a short surface connection over the discontinuities through the surface tension of the less viscous substance; and solidifying the substance after it forms the short surface connections so that it permanently becomes a portion of the stereolithography part.
Claim 19
Dependent Claim
179 words
In a stereolithographic method for forming a part from a material capable of selective physical transformation upon exposure to prescribed synergistic stimulation including forming successive cross-sectional patterns of the part on a selected surface of the material capable of selective physical transformation, relatively displacing the selected surface and said cross-sections as they are formed and building up the part layer by layer in a step-wise fashion, wherein the part has surface discontinuities between at least some adjacent layers, the improvement comprising the steps of: substantially coating at least a portion of the part surface with a substance which is capable of becoming less viscous when heated to a temperature which does not substantially thermally damage the part, the heated substance having an appropriate surface tension; heating the coated part to said temperature until said substance flows into the surface discontinuities and forms short surface connections across the discontinuities through the surface tension of the heated substance; and solidifying the substance after it forms the short surface connections so that it permanently becomes a portion of the stereolithographically produced part.
Claim 20
Dependent Claim
179 words
In a stereolithographic method for forming a part from a material capable of selective physical transformation upon exposure to prescribed synergistic stimulation including forming successive cross-sectional patterns of the part on a selected surface of the material capable of selective physical transformation, relatively displacing the selected surface and said cross-sections as they are formed and building up the part layer by layer in a step-wise fashion, wherein the part has surface discontinuities between at least some adjacent layers, the improvement comprising the steps of: substantially coating at least a portion of the part surface with a substance which is capable of becoming less viscous when heated to a temperature which does not substantially thermally damage the part, the heated substance having an appropriate surface tension; heating the coated part to said temperature until said substance flows into the surface discontinuities and forms short surface connections across the discontinuities through the surface tension of the heated substance; and solidifying the substance after it forms the short surface connections so that it permanently becomes a portion of the stereolithographically produced part.
Claim 21
Dependent Claim
11 words
The method of claim 16 wherein the substance is a powder.
Claim 22
Dependent Claim
11 words
The method of claim 16 wherein the substance is a liquid.
Claim 23
Dependent Claim
45 words
The method of claim 16 wherein the substance is thermally curable at a cure temperature which does not thermally degrade the part, and wherein the step of solidifying the melted powder further comprises heating the coated part at said cure temperature until the substance cures.
Claim 24
Dependent Claim
30 words
The method of claim 16 wherein the substance is UV curable, and the method further comprises the step of irradiating the coated part with UV light until the substance cures.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-08-09 | 1997-02-08 | 1997-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-09 | 2001-02-08 | 2001-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-09 | 2005-02-08 | 2005-08-10 | $7700.00 | Window Closed / Lapsed |