Method and apparatus for photo-curing with displaceable self-lubricating substratum for the formation of three-dimensional objects

Patent metadata

Field	Value
Publication number	US-2017129175-A1
Application number	US-201715415688-A
Country	US
Kind code	A1
Filing date	Jan 25, 2017
Priority date	Oct 2, 2015
Publication date	May 11, 2017
Grant date	—

Abstract

Three-dimensional objects are formed by photo-curing a liquid polymer by exposure to a radiation in a space between a sheet transparent to the radiation and a supporting plate. On a side of the sheet facing towards the photo-curing liquid polymer, a membrane is arranged. The membrane is transparent to the radiation and covered by a layer of liquid lubricant. The membrane is displaceable with respect to an area in which said liquid polymer is undergoing curing by exposure to the radiation, which radiation (e.g., at 410 nm) may be provided by a collimated light source composed of an array of light emitting diode (LED) sources, an array of baffles, and an array of lenses. The baffles limit beam widths of each individual LED source in the array of LED, and the array of lenses is located one focal length from said array of LED sources.

First claim

What is claimed is:

1 . A method for forming three-dimensional objects by photo-curing a photo-curing liquid polymer exposed to a radiation, wherein said three-dimensional objects form by growth, due to the progressive curing of said photo-curing liquid polymer, in the space between a sheet transparent to said radiation and a supporting plate, that is, a portion already formed of said objects, said supporting plate progressively moving away from said transparent sheet, characterised in that on a side of said transparent sheet facing towards said photo-curing liquid polymer a membrane is disposed, said membrane being transparent to said radiation and covered by a layer of liquid lubricant which is released gradually by said membrane, said membrane being displaceable with respect to an area in which said photo-curing liquid polymer is undergoing curing by said radiation thereby resulting in said growth.

2 . The method for forming three-dimensional objects according to claim 1 , characterised in that said membrane is made of a self-lubricating polymer.

3 . The method for forming three-dimensional objects according to claim 2 , characterised in that said self-lubricating polymer is a polymer inside of which there is a liquid lubricant.

4 . The method for forming three-dimensional objects according to claim 3 , characterised in that said displacement is lateral with respect to said area in which said photo-curing liquid polymer is undergoing curing.

5 . The method for forming three-dimensional objects according to claim 4 , characterised in that said lateral displacement is effected by dispensing said membrane from a first reel and taking up said membrane on a second reel, said first and second reels disposed on opposite sides of a tank in which said photo-curing liquid polymer is undergoing curing.

6 . The method for forming three-dimensional objects according to claim 5 , characterised in that said lateral displacement occurs at times when said supporting plate is raised vertically away from said transparent sheet.

7 . The method for forming three-dimensional objects according to claim 4 , characterised in that said self-lubricating polymer is a silicone polymer and said liquid lubricant is silicone oil.

8 . The method for forming three-dimensional objects according to claim 7 , characterised in that either or both of said silicone oil and said self-lubricating polymer is enriched with polytetrafluoroethylene (PTFE).

9 . The method for forming three-dimensional objects according to claim 4 , characterized in that said photo-curing liquid polymer undergoes curing by irradiation from a collimated light source including an array of light emitting diode (LED) sources.

10 . The method for forming three-dimensional objects according to claim 9 , characterized in that said LED sources emit radiation at a wavelength between 400-700 nm.

11 . The method for forming three-dimensional objects according to claim 9 , characterized in that said LED sources emit radiation at a wavelength of 410 nm.

12 . The method for forming three-dimensional objects according to claim 9 , characterized in that said collimated light source includes an array of baffles, and an array of lenses, said baffles arranged so as to limit a beam width of each individual LED source in the array of LED sources to approximately a diameter of a lens of the array of lenses, and the array of lenses is located one focal length from said array of LED sources.

13 . The method for forming three-dimensional objects according to claim 1 , characterized in that said photo-curing liquid polymer undergoes curing by irradiation from a collimated light source including an array of light emitting diode (LED) sources, an array of baffles, and an array of lenses, said baffles arranged so as to limit a beam width of each individual LED source in the array of LED sources to approximately a diameter of a lens of the array of lenses, and the array of lenses is located one focal length from said array of LED sources.

14 . An apparatus for forming three-dimensional objects by photo-curing a photo-curing liquid polymer by exposure to a radiation, comprising a tank for collecting said photo-curing liquid polymer, a bottom of the tank having a hole covered by a sheet made of a material transparent to said radiation, and a supporting plate configured to move away from the sheet, characterised in that, on a side of said sheet facing towards said photo-curing liquid polymer, a membrane is disposed, said membrane being transparent to said radiation and being covered by a layer of liquid lubricant which is released gradually by said membrane, wherein said membrane is disposed between a pair of reels opposite of one another such that a portion of said membrane between said reels passes through said tank, above said transparent sheet and below said photo-curing liquid polymer.

15 . The apparatus for forming three-dimensional objects according to claim 14 , characterised in that said membrane is made with a self-lubricating polymer, inside of which there is a liquid lubricant.

16 . The apparatus for forming three-dimensional objects according to claim 15 , characterised in that said self-lubricating polymer is silicone and said liquid lubricant is silicone oil.

17 . The apparatus for forming three-dimensional objects according to claim 14 , further comprising a collimated light source to emit said radiation by which said photo-curing liquid polymer undergoes curing.

18 . The apparatus for forming three-dimensional objects according to claim 17 , wherein said collimated light source comprises an array of light emitting diode (LED) sources configured to emit radiation at a wavelength between 400-700 nm.

19 . The apparatus for forming three-dimensional objects according to claim 17 , wherein said collimated light source comprises an array of light emitting diode (LED) sources configured to emit radiation at a wavelength of 410 nm.

20 . The apparatus for forming three-dimensional objects according to claim 14 , wherein said collimated light source comprises an array of light emitting diode (LED) sources, an array of baffles, and an array of lenses, said baffles arranged so as to limit a beam width of each individual LED source in the array of LED sources to approximately a diameter of a lens of the array of lenses, and the array of lenses is located one focal length from said array of LED sources.

Assignees

• Nexa3D Inc

Inventors

• Zitelli Gianni
• Reichental Avi N
• Tringali Luciano

Classifications

• B29C64/182

  in parallel batches · CPC title

• B29K2105/0058

  Liquid or visquous · CPC title

• B29C64/223

  Foils or films, e.g. for transferring layers of building material from one working station to another · CPC title

• B29C37/0067

  Using separating agents during or after moulding; Applying separating agents on preforms or articles, e.g. to prevent sticking to each other (separating agents B29C33/60) · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title