WO2020113200A1

WO2020113200A1 - System and method for three-dimensional production

Info

Publication number: WO2020113200A1
Application number: PCT/US2019/063904
Authority: WO
Inventors: Peidong Han
Original assignee: Innovamake, Inc.
Priority date: 2018-12-01
Filing date: 2019-12-01
Publication date: 2020-06-04

Abstract

The present disclosure provides a system and method for three-dimensional production processes.

Description

SYSTEM AND METHOD FOR THREE-DIMENSIONAL PRODUCTION

PRIORITY CLAIM

[0001] The present application claims priority to U.S. Provisional Patent Application Serial No. 62/774,220, filed December 1 , 2018, the entire contents of which are incorporated herein and relied upon.

FIELD OF THE DISCLOSURE

[0002] The present disclosure provides a system and method for three-dimensional production processes.

BACKGROUND

[0003] A three-dimensional object may be produced from a liquid photopolymer in a layer-by- layer manner. In one such process, a controlled light source selectively irradiates the liquid photopolymer through an optically transparent plate. The irradiated liquid photopolymer solidifies to form a layer of the object being produced on the plate. The layer is then separated from the plate. Subsequent layers are created in the same manner until the object is complete.

[0004] One crucial step of the above process is to separate the solidified layers from the plate. A polymerization inhibitor such as oxygen is often supplied from or through the plate to the adjacent liquid photopolymer to facilitate the separation of solidified layers. This is based on the ability of oxygen to inhibit free radical polymerization, commonly known as oxygen inhibition. Oxygen inhibition creates a polymerization inhibition layer between the solidified layer and the plate, preventing the solidified layer from adhering to the plate. Maintaining a polymerization inhibition layer is crucial to the success of the three-dimensional production process. Oxygen supply and flux of oxygen are important factors in maintaining the polymerization inhibition layer. High flux of oxygen is desired as it increases the thickness of the polymerization inhibition layer, which lowers the force to separate the solidified layers from the plate and increases the speed and reliability of the three-dimensional production process.

[0005] In the Form 2 three-dimensional printer by Formlabs (Somerville, Massachusetts,

USA) and the B9Creator three-dimensional printer by B9creations (Deadwood, South Dakota, USA), the optically transparent plate comprises a polydimethylsiloxane (PDMS) coating which absorbs oxygen when it is exposed to oxygen in the form of a gas. The amount of oxygen dissolved in PDMS obeys Henry’s law and is proportional to the partial pressure of oxygen above the PDMS. The dissolved oxygen diffuses from PDMS to the adjacent liquid photopolymer to create the polymerization inhibition layer during three-dimensional production. The PDMS coating of the Form 2 and B9Creator three-dimensional printers is configured to absorb oxygen from ambient air by exposing PDMS to air after the construction of each layer in order to keep the oxygen in the PDMS coating from being depleted during the three-dimensional production. Specifically, a wiper blade is utilized to expose PDMS to air by wiping off the liquid photopolymer from the PDMS coating after the construction of each layer. The drawbacks of the wiping step are: (1 ) it significantly slows down the three-dimensional production process; and (2) it may also damage the PDMS coating. In addition, the amount of oxygen dissolved in the PDMS coating is limited by the low oxygen partial pressure in ambient air (about 3.1 psia), which limits the concentration of oxygen in the PDMS coating and the flux of oxygen from the PDMS coating to the liquid photopolymer during three-dimensional production.

[0006] In the M2 three-dimensional printer by Carbon (Redwood City, California, USA), the optically transparent plate comprises a 100pm thick amorphous fluoropolymer window (Teflon AF 2400) with excellent oxygen permeability (990 barrers). Oxygen in ambient air permeates through the Teflon AF 2400 window to the adjacent liquid photopolymer to create the

polymerization inhibition layer. The oxygen permeable window continuously maintains the polymerization inhibition layer without the mechanical steps. However, the major drawbacks are: (1 ) the cost of Teflon AF 2400 is very high; and (2) the flux of oxygen through the window is limited by the oxygen partial pressure in ambient air. High oxygen pressure may be provided by enclosing the three-dimensional printer in a pressure vessel and carrying the process out in a pressurized atmosphere. However, the cost of a large high-pressure vessel and the associated operating cost make the three-dimensional production process more expensive.

[0007] There remains a need for more efficient and economical methods of additive printing using liquid photopolymer materials.

SUMMARY

[0008] In one embodiment, the present disclosure provides a system for charging a polymerization inhibitor absorbing member for three-dimensional production, comprising: a container configured to enclose the polymerization inhibitor absorbing member; and a polymerization inhibitor source configured to supply a gas comprising a polymerization inhibitor to the container.

[0009] In another embodiment, the present disclosure provides a self-charging vat system comprising: a vat configured to hold a liquid photopolymer for three-dimensional production, the vat comprising an optically transparent polymerization inhibitor absorbing member; a lid for covering the vat to form an enclosed space with at least a portion of the surface of the polymerization inhibitor absorbing member in the enclosed space; and at least one opening in the lid or in the vat configured to allow a polymerization inhibitor to pass into or out of the enclosed space.

[0010] In another embodiment, the present disclosure provides a vat configured to hold a liquid photopolymer for three-dimensional production, the vat comprising: an optically transparent polymerization inhibitor absorbing member; and at least one foot configured to orient the vat in a non-horizontal angled configuration.

[0011] In another embodiment, the present disclosure provides a method for charging a polymerization inhibitor absorbing member, the method comprising: enclosing at least a portion of the surface of the polymerization inhibitor absorbing member in a chamber; supplying a gas comprising at least about 21% polymerization inhibitor to the chamber; and contacting the polymerization inhibitor absorbing member with the gas for a period of time sufficient for at least a portion of the polymerization inhibitor to be absorbed by the polymerization inhibitor absorbing member.

[0012] In another embodiment, the present disclosure provides a method for producing a three-dimensional object, the method comprising: (a) providing a vat configured to hold a liquid photopolymer for three-dimensional production, wherein the vat comprises an optically transparent polymerization inhibitor absorbing member; (b) contacting the polymerization inhibitor absorbing member with a gas comprising a polymerization inhibitor for a period of time sufficient for at least a portion of the polymerization inhibitor to be absorbed by the

polymerization inhibitor absorbing member; (c) contacting the polymerization inhibitor absorbing member with a liquid photopolymer within the vat; (d) irradiating the liquid photopolymer through the polymerization inhibitor absorbing member in a build region of the vat between the polymerization inhibitor absorbing member and a carrier plate to form a solid polymerized region adhered to the carrier plate; (e) advancing the carrier plate away from the polymerization inhibitor absorbing member to create a subsequent build region between the solid polymerized region and the polymerization inhibitor absorbing member; and (f) repeating steps (d) and (e) to produce a subsequent solid polymerized region adhered to the solid polymerized region until the three-dimensional object is complete. BRIEF DESCRIPTION OF THE FIGURES

[0013] FIG. 1 A and 1 B show a plan view of a vat for 3-dimensional production comprising an optically transparent polymerization inhibitor absorbing member consistent with one

embodiment of the present disclosure;

[0014] FIGS. 2A and 2B show a plan view of a system for charging the polymerization inhibitor absorbing member for 3-dimensional production consistent with one embodiment of the present disclosure.

[0015] FIG. 3 shows a plan view of a self-charging vat system consistent with one

embodiment of the present disclosure.

[0016] FIG. 4 shows a flowchart illustrating a method for charging the polymerization inhibitor absorbing member of a system for 3-dimensional production consistent with one embodiment of the present disclosure.

[0017] FIGS. 5A and 5B show a plan view of a system for charging the polymerization inhibitor absorbing member for 3-dimensional production consistent with one embodiment of the present disclosure.

[0018] FIG. 6 shows a plan view of an embodiment of a vat for 3-dimensional production consistent with one embodiment of the present disclosure.

[0019] FIG. 7 shows a plan view of a system for 3-dimensional production consistent with one embodiment of the present disclosure.

[0020] FIG. 8 shows a flowchart illustrating a three-dimensional production method consistent with one embodiment of the present disclosure.

[0021] While specific embodiments are illustrated in the figures, with the understanding that the disclosure is intended to be illustrative, these embodiments are not intended to limit the invention described and illustrated herein.

DETAILED DESCRIPTION

[0022] Various embodiments of the present disclosure will be described in detail with reference to the drawings, where like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the present disclosure, which is limited only by the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the claimed inventions.

[0023] FIGS. 1 A-1 B show schematic illustrations of embodiments of a vat 100, which is configured to be used with a three-dimensional production apparatus. The vat 100 is configured to hold a liquid photopolymer 30 for three-dimensional production processes.

[0024] The vat 100 includes walls 20 that may or may not be optically transparent, and a bottom 10, wherein at least a portion of the bottom of the vat is optically transparent. The bottom 10 comprises a polymerization inhibitor absorbing member 15 that absorbs a polymerization inhibitor 55 when it is exposed to (e.g., contacted with) the polymerization inhibitor 55 in the form of a gas. The amount of absorbed polymerization inhibitor 55 depends on the partial pressure of the polymerization inhibitor 55 above the polymerization inhibitor absorbing member 15. In some embodiments, the bottom 10 may comprise an optically transparent supporting plate or film 16 made of glass, acrylic, FEP, PTFE, PFA, or any other optically transparent material (FIG. 1 B).

[0025] In general, the amount of polymerization inhibitor 55 absorbed by the polymerization inhibitor absorbing member 15 is approximately proportional to the partial pressure of the polymerization inhibitor 55 in the gas. The amount of polymerization inhibitor 55 absorbed by the polymerization inhibitor absorbing member 15 will also depend on the thickness of the polymerization inhibitor absorbing member 15. In general, the thickness of the polymerization inhibitor absorbing member 15 is at least about 1 mm, for example at least about 1 mm, at least about 1.1 mm, at least about 1.2 mm, at least about 1.3 mm, at least about 1.4 mm, at least about 1.5 mm, at least about 1.6 mm, at least about 1.7 mm, at least about 1.8 mm, at least about 1.9 mm, at least about 2 mm, at least about 2.1 mm, at least about 2.2 mm, at least about 2.3 mm, at least about 2.4 mm, at least about 2.5 mm, at least about 2.6 mm, at least about 2.7 mm, at least about 2.8 mm, at least about 2.9 mm, or at least about 3 mm.

[0026] The polymerization inhibitor 55 may be any suitable polymerization inhibitor (e.g., a free radical polymerization inhibitor) that is in the form of a gas. In some embodiments, for example, the polymerization inhibitor 55 is oxygen.

[0027] The polymerization inhibitor absorbing member 15 may be made of any suitable materials that absorb the polymerization inhibitor 55 (e.g., oxygen) and are optically transparent. In some embodiments, the polymerization inhibitor absorbing member 15 comprises, consists essentially of, or consists of a siloxane polymer such as polydimethylsiloxane (PDMS). In other embodiments, the polymerization inhibitor absorbing member 15 is a fluoropolymer such as poly[4,5-difluoro-2,2-bis(trifluoromethyl)-1 ,3-dioxole-co-tetrafluoroethylene] - dioxole 87 mol % (Teflon AF 2400) or poly[4,5-difluoro-2,2-bis(trifluoromethyl)-1 ,3-dioxole-co-tetrafluoroethylene] - dioxole 65 mol % (Teflon AF 1600). In some embodiments, the polymerization inhibitor absorbing member 15 is a combination of one or more siloxane polymer and one or more fluoropolymer.

[0028] Referring now to FIGS. 2A-2B, a system 200 for charging the polymerization inhibitor absorbing member 15. The system 200 comprises a container 40 configured to enclose the polymerization inhibitor absorbing member 15, and optionally also the vat 100. The container 40 is configured to operate at a working pressure of about 0 psia and about 200 psia, for example about 0 psia, about 5 psia, about 10 psia, about 15 psia, about 20 psia, about 25 psia, about 30 psia, about 35 psia, about 40 psia, about 45 psia, about 50 psia, about 75 psia, about 100 psia, about 125 psia, about 150 psia, about 175 psia, or about 200 psia. In some embodiments, the system 200 includes a lid 45 (FIG. 2B).

[0029] The system 200 further comprises a polymerization inhibitor source 50 configured to supply a gas comprising the polymerization inhibitor 55 to the container 40. In some

embodiments, the polymerization inhibitor source 50 may be configured to supply the polymerization inhibitor 55 to the container 40 through a tube 52. In other embodiments, the polymerization inhibitor source 50 may be configured to be inside the container 40. In some embodiments, the polymerization inhibitor source 50 and/or the tube 52 includes a valve for controlling delivery of the polymerization inhibitor 55 from the polymerization inhibitor source 50 to the container 40.

[0030] In some embodiments, the gas comprising the polymerization inhibitor 55 is air.

In such embodiments, the polymerization inhibitor source 50 may be an air compressor or a tank containing compressed air. By volume, air only contains 20.95% oxygen and thus the partial pressure of oxygen is only 20.95% of the total air pressure. For example, air at atmospheric pressure of 14.7 psia has an oxygen partial pressure of 3.1 psia. Air compressed at 47.7 psia has an oxygen partial pressure of 10 psia. In some embodiments, the gas includes at least 21 % oxygen, such as at least 21 % oxygen, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about

33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about

41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about

49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61 %, about 62%, about 63%, about 64%, about

65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about

73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about

81 %, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about

89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about

97%, about 98%, about 99%, or about 100% (i.e., pure oxygen). For example, when a gas mixture containing 50% oxygen is used, a pressure of 20psia will result in a 10psia oxygen partial pressure. In some embodiments, the polymerization inhibitor source 50 is an oxygen generator/concentrator utilizing pressure swing adsorption (PSA) technology, an oxygen generator based on hydrogen peroxide (H₂0 ) and a catalyst, or a cylinder/tank filled with a gas enriched with oxygen. In some embodiments, the polymerization inhibitor source 50 is an oxygen generator including hydrogen peroxide and a catalyst such as manganese oxide or a heterogeneous molybdenum-based catalyst.

[0031] In general, polymerization inhibitor sources 50 that provide a higher ratio of oxygen to other gases provides more efficient production of three-dimensionally printed products. In addition, polymerization inhibitor sources 50 that provide a higher ratio of oxygen to other gases reduces the need for a container 40 to operate at high pressures, and can therefore reduce the cost of manufacture of the container 40 compared to containers 40 that must operate at higher pressures to enable absorption of a similar amount of oxygen from a gas including a relatively low amount of oxygen.

[0032] Referring now to FIG. 3, a self-charging vat system 400 consistent with the present disclosure comprises a vat 100 configured to hold a liquid photopolymer 30 for three- dimensional production. The vat 100 comprises an optically transparent polymerization inhibitor absorbing member 15. The self-charging vat system 400 further comprises a lid 60 for covering the vat 100 to form an enclosed space with at least a portion of the surface of the polymerization inhibitor absorbing member 15 in the enclosed space. The vat 100 and lid 60 may or may not form an airtight seal. The self-charging vat system 400 further comprises at least one opening 65 configured to enable a polymerization inhibitor 55 to pass into or out of the enclosed space, for example from a polymerization inhibitor source 50 and optionally a tube 52 disposed between the polymerization inhibitor source 50 and the vat 100 or lid 60. In some embodiments, the opening 65 is in the lid 60. In other embodiments, the opening 65 is in a wall 20 of the vat 100. [0033] Referring now to FIG. 4, a method for charging a polymerization inhibitor absorbing member 15 begins (step 510) by enclosing at least a portion of the surface of the polymerization inhibitor absorbing member 15 in a chamber (e.g., container 40 or vat 100) (step 520). Once step 520 is completed, a step 530 of supplying a gas including a polymerization inhibitor 55 to the chamber is performed. In some embodiments, the gas includes at least 21% polymerization inhibitor. In some embodiments, the step 530 of supplying the gas comprises providing a flow of the gas into an opening 65 into the chamber. The method 500 further comprises a step 540 of contacting (or maintaining contact) the polymerization inhibitor absorbing member 15 with the gas including the polymerization inhibitor 55. The step 540 of contacting (or maintaining contact) may occur immediately after the step 530 of supplying the gas, for example without further action or intervention by a user. The step 540 of contacting or maintaining contact between the polymerization inhibitor absorbing member 15 and the gas including the

polymerization inhibitor 55 may occur for a period of time sufficient for at least a portion of the polymerization inhibitor to be absorbed by the polymerization inhibitor absorbing member. In some embodiments, step 540 occurs for at least about 30 seconds to not more than about 15 minutes so that the polymerization inhibitor absorbing member 15 absorbs sufficient

polymerization inhibitor 55 for one three-dimensional production run, for example at least about 30 seconds, 1 minute, about 1.5 minutes, about 2 minutes, about 2.5 minutes, about 3 minutes, about 3.5 minutes, about 4 minutes, about 4.5 minutes, about 5 minutes, about 5.5 minutes, about 6 minutes, about 6.5 minutes, about 7 minutes, about 7.5 minutes, about 8 minutes, about

8.5 minutes, about 9 minutes, about 9.5 minutes, about 10 minutes, about 10.5 minutes, about 1 1 minutes, about 1 1.5 minutes, about 12 minutes, about 12.5 minutes, about 13 minutes, about

13.5 minutes, about 14 minutes, about 14.5 minutes, or about 15 minutes. In some

embodiments, the time period is about 5 minutes. In some embodiments, step 540 occurs for a time period sufficient for the polymerization inhibitor absorbing member 15 absorbs sufficient polymerization inhibitor 55 for multiple three-dimensional production runs, for example wherein the time period is at least about 15 minutes, such as 15 minutes, at least about 20 minutes, at least about 25 minutes, at least about 30 minutes, at least about 35 minutes, at least about 40 minutes, at least about 45 minutes, at least about 50 minutes, at least about 55 minutes, at least about 60 minutes, or even for one or more hours. In some embodiments, the time period is about 1 hour. In some embodiments, step 540 occurs overnight so that the polymerization inhibitor absorbing member 15 may be immediately used the next working day. The partial pressure of the polymerization inhibitor 55 in step 540 may be about 5 psia to about 100 psia, or more than about 100 psia, for example about 5 psia, about 10 psia, about 15 psia, about 20 psia, about 25 psia, about 30 psia, about 35 psia, about 40 psia, about 45 psia, about 50 psia, about 55 psia, about 60 psia, about 65 psia, about 70 psia, about 75 psia, about 80 psia, about 85 psia, about 90 psia, about 95 psia, about 100 psia, or more than about 100 psia.

[0034] In some embodiments, the polymerization inhibitor absorbing member 15 is charged (e.g., absorbs the polymerization inhibitor 55) before the vat 100 is filled with the liquid photopolymer 30. In other embodiments, the polymerization inhibitor absorbing member 15 is charged with the liquid photopolymer 30 already in the vat 100, for example, by recharging the polymerization inhibitor absorbing member 15 with additional polymerization inhibitor 55 after one or more production runs without first removing the liquid photopolymer 30 from the vat 100. In a representative embodiment, the method comprises providing a gas as disclosed herein including a polymerization inhibitor 55, for example via a polymerization inhibitor source 50, to a chamber (e.g., a container 40 or a vat 100) that includes a liquid photopolymer 30.

[0035] Referring now to FIG. 5A, a system 600 for charging a polymerization inhibitor absorbing member 15 with a liquid photopolymer 30 already in the vat 100 is performed with the vat 100 oriented in an angled position such that at least a portion of the polymerization inhibitor absorbing member 15 is exposed to the gas including the polymerization inhibitor 55. In some embodiments, such as those consistent with the embodiment shown in FIG. 5B, the vat 100 may include a build area 22 comprising the polymerization inhibitor absorbing member 15, and a non-build area 24 that may or may not include the polymerization inhibitor absorbing member 15. In operation, producing a three-dimensionally printed product using a system 600 consistent with FIGS. 5A-5B comprises charging the polymerization inhibitor absorbing member 15 while the vat 100 is oriented in an angled position, and thereafter producing the three- dimensionally printed product while the vat 100 is oriented in a position that is substantially horizontal.

[0036] As shown in FIG. 6, the vat 100 may include at least one foot 28 configured to orient the vat 100 in an angled position, for example to expose at least a portion of the polymerization inhibitor absorbing member 15 above the level of the liquid photopolymer 30.

[0037] Referring now to FIG. 7, an iterative method of producing a three-dimensional product comprises charging a polymerization inhibitor absorbing member 15 of a vat 100 with a polymerization inhibitor 55, disposing a liquid polymer 30 to a build region BR between the polymerization inhibitor absorbing member 15 and a carrier plate 70, and thereafter exposing the liquid photopolymer 30 within the build region BR to a light source 80, such as a laser light source or projector, to form a solid polymerized layer SPL of the three-dimensional object TDO. After formation of the solid polymerized layer SPL, the carrier plate 70 is advanced away from the polymerization inhibitor absorbing member 15 by an actuator (shown representatively by arrows 90) to form a subsequent build region BR between the solid polymerized layer SPL and the polymerization inhibitor absorbing member 15. In embodiments consistent with the present disclosure, a subsequent solid polymerized layer SPL is then produced (e.g., by exposing the liquid polymer 30 within the build region BR to light from the light source 80) without requiring a step of wiping the liquid polymer 30 from the surface of the polymerization inhibitor absorbing member 15. Without wishing to be bound by theory, it is believed that the polymerization inhibitor 55 diffuses from the polymerization inhibitor absorbing member 15 to form an unpolymerized liquid layer (also known as polymerization inhibition layer, or dead zone) 35 within the liquid polymer 30 adjacent to the polymerization inhibitor absorbing member 15 in a sufficient amount to promote release of the solid polymerized layer SPL from the polymerization inhibitor absorbing member 15.

[0038] Referring now to FIG. 8, a three-dimensional production method 800 consistent with the present disclosure begins (step 810) comprises a step 820 of providing a vat 100 configured to hold a liquid photopolymer 30 for three-dimensional production, said vat 100 comprising an optically transparent polymerization inhibitor absorbing member 15. Thereafter, the method 800 includes performing a step 830 of exposing the polymerization inhibitor absorbing member 15 to a gas including a polymerization inhibitor 55 to charge the polymerization inhibitor absorbing member 15 with the polymerization inhibitor 55. In some embodiments, the gas comprises at least 21 % polymerization inhibitor 55. The method 800 further includes a step 840 of thereafter contacting the polymerization inhibitor absorbing member 15 with a liquid polymer 30 (e.g., filling the vat 100 at least partially with a liquid photopolymer 30). The method 800 further includes a step 850 of thereafter irradiating the liquid photopolymer 30 in the build region BR through the polymerization inhibitor absorbing member 15 to form a solid polymerized layer SPL adhered to the carrier plate 70. After the solid polymerized layer SPL is formed, the method 800 further includes a step 860 of advancing the carrier plate 70 away from the polymerization inhibitor absorbing member 15 to create a subsequent build region BR between the solid polymerized layer SPL and the polymerization inhibitor absorbing member 15. The method 800 may optionally include repeating step 850 and step 860 to produce subsequent solid

polymerized layers SPL adhered to each previous solid polymerized layer SPL until the three- dimensional object TDO is complete. In some embodiments, step 850 and step 860 are carried out sequentially. In other embodiments, step 850 and step 860 are carried out concurrently, for example to provide a more continuous or continuous process for producing a three-dimensional object TDO.

[0039] Three-dimensional production methods and systems consistent with the present disclosure require no mechanical steps to replenish the polymerization inhibitor absorbing member 15 during the production run, significantly reducing the time required to produce a three-dimensional object TDO.

[0040] Three-dimensional production methods and systems consistent with the present disclosure increase efficiency (e.g., speed) and reliability by providing an increased

amount/concentration of the polymerization inhibitor 55 dissolved in the polymerization inhibitor absorbing member 15, thereby increasing the flux of polymerization inhibitor 55 (e.g., oxygen) to the liquid photopolymer 30 in the build region BR during three-dimensional production. The high flux of polymerization inhibitor 55 during the production run increases the thickness of the polymerization inhibition layer 35, which lowers the force required to release the solid polymerized layers.

[0041] Methods and systems of the present disclosure considerably reduce the cost by charging the polymerization inhibitor absorbing member 15 before a production run instead of operating a three-dimensional apparatus in a pressurized atmosphere because the

polymerization inhibitor absorbing member 15 is one or two orders of magnitude smaller (e.g., in dimension) than currently available three-dimensional production apparatus.

[0042] Methods and systems of the present disclosure reduce/slow down the clouding issue that occurs to the polymerization inhibitor absorbing member 15 (e.g., PDMS) during three- dimensional production.

[0043] Although the present disclosure has been described in detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein. Further, it will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure covers modifications and variations of this disclosure provided they fall within the scope of the following claims.

Claims

WHAT IS CLAIMED IS:

1. A system for charging a polymerization inhibitor absorbing member for three-dimensional production, comprising:

a container configured to enclose the polymerization inhibitor absorbing member; and a polymerization inhibitor source configured to supply a gas comprising a polymerization inhibitor to the container

2. The system of claim 1 further comprising a lid associated with the container.

3. The system of claim 1 or claim 2, wherein the chamber has a working pressure of between Opsia and 200psia.

4. The system of any one preceding claim, wherein the polymerization inhibitor source is an oxygen generator or an oxygen concentrator.

5. The system of any one preceding claim, wherein the polymerization inhibitor comprises oxygen.

6. The system of any one preceding claim, wherein the gas comprises oxygen.

7. The system of any one preceding claim, wherein the gas comprises air enriched with oxygen.

8. The system of any one preceding claim, wherein the partial pressure of the polymerization inhibitor is at least 5psia.

9. The system of any one preceding claim, wherein the gas comprises at least 21%

polymerization inhibitor.

10. The system of any one preceding claim, wherein the polymerization inhibitor absorbing member comprises, consists essentially of, or consists of polydimethylsiloxane (PDMS).

1 1 . A self-charging vat system comprising:

a vat configured to hold a liquid photopolymer for three-dimensional production, the vat comprising an optically transparent polymerization inhibitor absorbing member;

a lid for covering the vat to form an enclosed space with at least a portion of the surface of the polymerization inhibitor absorbing member in the enclosed space; and

at least one opening in the lid or in the vat configured to allow a polymerization inhibitor to pass into or out of the enclosed space.

12. The system of claim 1 1 , wherein the polymerization inhibitor absorbing member comprises, consists essentially of, or consists of polydimethylsiloxane (PDMS).

13. The system of claim 1 1 or claim 12, wherein the vat comprises a build area comprising the polymerization inhibitor absorbing member and a non-build area.

14. The system of any one of claims 1 1 -13, wherein the opening is in the lid.

15. The system of any one of claims 1 1 -13, wherein the opening is in the vat.

16. A vat configured to hold a liquid photopolymer for three-dimensional production, the vat comprising:

an optically transparent polymerization inhibitor absorbing member; and

at least one foot configured to orient the vat in a non-horizontal angled configuration.

17. A method for charging a polymerization inhibitor absorbing member, the method comprising: enclosing at least a portion of the surface of the polymerization inhibitor absorbing member in a chamber;

supplying a gas comprising at least about 21 % polymerization inhibitor to the chamber; and

contacting the polymerization inhibitor absorbing member with the gas for a period of time sufficient for at least a portion of the polymerization inhibitor to be absorbed by the polymerization inhibitor absorbing member.

18. The method of claim 17, wherein the polymerization inhibitor absorbing member is oriented in an angled position within the chamber.

19. The method of claim 17 or claim 18, wherein the polymerization inhibitor absorbing member comprises a siloxane polymer (e.g., PDMS).

20. The method of any one of claims 17-19, wherein the polymerization inhibitor comprises, consists essentially of, or consists of oxygen.

21 . The method of any one of claims 17-20, wherein the step of supplying a gas comprises filling the chamber to a polymerization inhibitor partial pressure of at least about 5 psia.

22. The method of any one of claims 17-21 , wherein the period of time is at least about 3 minutes.

23. A method for producing a three-dimensional object, the method comprising:

(a) providing a vat configured to hold a liquid photopolymer for three-dimensional production, wherein the vat comprises an optically transparent polymerization inhibitor absorbing member;

(b) contacting the polymerization inhibitor absorbing member with a gas comprising a polymerization inhibitor for a period of time sufficient for at least a portion of the polymerization inhibitor to be absorbed by the polymerization inhibitor absorbing member;

(c) contacting the polymerization inhibitor absorbing member with a liquid photopolymer within the vat;

(d) irradiating the liquid photopolymer through the polymerization inhibitor absorbing member in a build region of the vat between the polymerization inhibitor absorbing member and a carrier plate to form a solid polymerized region adhered to the carrier plate;

(e) advancing the carrier plate away from the polymerization inhibitor absorbing member to create a subsequent build region between the solid polymerized region and the polymerization inhibitor absorbing member; and

(f) repeating steps (d) and (e) to produce a subsequent solid polymerized region adhered to the solid polymerized region until the three-dimensional object is complete.

24. The method of claim 23, wherein steps (d) and (e) are carried out sequentially.

25. The method of claim 23, wherein steps (d) and (e) are carried out concurrently.

26. The method of any one of claims 23-25, wherein the gas comprises at least 21 %

polymerization inhibitor.

27. The method of claim 23-26, wherein the polymerization inhibitor absorbing member comprises polydimethylsiloxane (PDMS).