WO2024050344A1 - Fabrication additive de polymères thermodurcissables par durcissement laser thermique - Google Patents

Fabrication additive de polymères thermodurcissables par durcissement laser thermique Download PDF

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Publication number
WO2024050344A1
WO2024050344A1 PCT/US2023/073060 US2023073060W WO2024050344A1 WO 2024050344 A1 WO2024050344 A1 WO 2024050344A1 US 2023073060 W US2023073060 W US 2023073060W WO 2024050344 A1 WO2024050344 A1 WO 2024050344A1
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Prior art keywords
heat curable
layer
cured
pdms
curable mixture
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PCT/US2023/073060
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English (en)
Inventor
Jeffrey Schultz
Simeon Brown
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Phase, Inc.
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Priority claimed from PCT/US2023/065371 external-priority patent/WO2023196848A1/fr
Application filed by Phase, Inc. filed Critical Phase, Inc.
Publication of WO2024050344A1 publication Critical patent/WO2024050344A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
    • B29C64/10—Processes of additive manufacturing
    • B29C64/106—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
    • B29C64/124—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified
    • B29C64/129—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified characterised by the energy source therefor, e.g. by global irradiation combined with a mask
    • B29C64/135—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified characterised by the energy source therefor, e.g. by global irradiation combined with a mask the energy source being concentrated, e.g. scanning lasers or focused light sources
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/502707—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by the manufacture of the container or its components
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/502715—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/502753—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by bulk separation arrangements on lab-on-a-chip devices, e.g. for filtration or centrifugation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
    • B29C64/20—Apparatus for additive manufacturing; Details thereof or accessories therefor
    • B29C64/205—Means for applying layers
    • B29C64/214—Doctor blades
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
    • B29C64/20—Apparatus for additive manufacturing; Details thereof or accessories therefor
    • B29C64/264—Arrangements for irradiation
    • B29C64/268—Arrangements for irradiation using laser beams; using electron beams [EB]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y10/00—Processes of additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y30/00—Apparatus for additive manufacturing; Details thereof or accessories therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y70/00—Materials specially adapted for additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2200/00—Solutions for specific problems relating to chemical or physical laboratory apparatus
    • B01L2200/06—Fluid handling related problems
    • B01L2200/0689—Sealing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2300/00—Additional constructional details
    • B01L2300/06—Auxiliary integrated devices, integrated components
    • B01L2300/0627—Sensor or part of a sensor is integrated
    • B01L2300/0645—Electrodes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2300/00—Additional constructional details
    • B01L2300/08—Geometry, shape and general structure
    • B01L2300/0809—Geometry, shape and general structure rectangular shaped
    • B01L2300/0816—Cards, e.g. flat sample carriers usually with flow in two horizontal directions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2300/00—Additional constructional details
    • B01L2300/08—Geometry, shape and general structure
    • B01L2300/0861—Configuration of multiple channels and/or chambers in a single devices
    • B01L2300/0877—Flow chambers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2300/00—Additional constructional details
    • B01L2300/08—Geometry, shape and general structure
    • B01L2300/0887—Laminated structure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2400/00—Moving or stopping fluids
    • B01L2400/06—Valves, specific forms thereof
    • B01L2400/0633—Valves, specific forms thereof with moving parts
    • B01L2400/0638—Valves, specific forms thereof with moving parts membrane valves, flap valves

Definitions

  • additive Manufacturing also known as three-dimensional (3D) printing has received attention for printing optics and microfluidic structures.
  • PDMS polydimethylsiloxane
  • UV curing is typically accomplished by initiating a reaction upon being exposed to UV light in the UVB (280-320nm) or UVA (320- 395nm) spectra.
  • PDMS does not absorb light in these ranges and therefore a UV absorbing additive is required. This adds another component to the PDMS part.
  • UV curing is considered the “go to” approach for manufacturing parts from PDMS.
  • these parts are considered inferior by the research community which wants the traditional PDMS with hardener to conduct its research.
  • Riahi, et al in their article titled “Fabrication of 3D microfluidic structure with direct selective laser baking of PDMS” used a CO2 laser having a wavelength of 10.6 micrometer (10,600 nm) to cure a mixture of PolyDiMethyl Siloxane and a hardener in an additive manufacturing layer-by-layer process.
  • Riahi ’s process sequentially lowered the part into a vat of PDMS mixture with the PDMS and then recoated the PDMS across the top of the part to form the next layer which is then cured.
  • the re-coater is a typical industry re-coater which wipes the PDMS from the vat (PDMS Mixture). Because the part is lowered into the vat, the PDMS in the vat is slightly higher than the part due to the PDMS’s viscosity and surface tension and the re-coater just slides across the part taking some of the slighter higher PDMS with it.
  • Riahi No microfluidic devices are demonstrated in Riahi.
  • Riahi s images and micrographs show that what should be optically clear is not.
  • the demonstration images have poor optical clarity, even opaque, and a significant number of large, trapped air bubbles or debris are visible.
  • the curing depth of PDMS with the laser was around 200 micrometers. This large curing depth is reportedly associated with the limited accuracy of the VAT POLYMERIZATION 3D printing techniques.
  • This specification discloses a method of additively manufacturing a heat cured article from a heat curable mixture.
  • the method comprises the steps of creating a puddle of the heat curable mixture at a position on a build stage, forming at least a portion of the puddle into a heat curable current layer L(n) having a layer thickness T(n), wherein forming comprises translating the heat curable mixture with a re-coater blade across the build stage for a first layer L(0) or translating the heat curable mixture with the re-coater blade across a preceding layer L(n- 1) when there is already a first layer, curing at least a portion of the heat curable current layer by applying an incident electromagnetic radiation energy to at least a portion of the heat curable current layer and optionally leaving an uncured portion of the heat curable current layer, wherein the incident electromagnetic radiation energy has at least one wavelength (X) wherein the heat curable mixture transmits less than 50% of the incident electromagnetic radiation energy per micron of the heat curable mixture at the at the at
  • the at least one wavelength is in a range of 9.2 to 9.4 micrometers or in a range of 190 to 275 nanometers.
  • the heat curable mixture comprises PDMS. It also teaches that the heat curable mixture may comprises a PDMS weight percent and a hardener weight percent totaling 100 weight percent.
  • the specification further discloses the heat curable mixture transmits at least 90% of an energy at each wavelength per micron of heat curable mixture in a wavelength range of 280 to 395 nanometers.
  • the re-coater blade used in the method is a knife-edged blade which may have an edge apex thickness of less than 500 micrometers or less than 200 micrometers.
  • the re-coater blade is at a tilt angle of less than 90 degrees or within a range of 15 to 85 degrees, or within a range of 40 to 50 degrees.
  • This specification also teaches a method of creating a heat curable layer L(n+1) having a thickness of T(n+1) of a heat curable mixture on a cured top layer L(n) of a heat cured part located on a build stage with the heat cured part having a heat cured part height above the build stage.
  • the method comprises placing a puddle of a heat curable mixture on the build stage having a puddle height above the build stage at 5 seconds after being placed on the build stage, wherein the puddle height is less than the heat cured part height, translating the puddle in an X direction toward the heat cured part with a re-coater blade having a re- coater blade end until a portion of the heat curable mixture is forced in a Z direction and is above, and on top of, the cured top layer; translating the puddle in the Z direction with the re-coater blade so that the re- coater blade end is above the cured top layer L(n) so that a gap between the re- coater blade and the cured top layer is equal to the thickness T(n+1) of the heat curable layer L(n+1), and then forming the heat curable layer L(n+1) on the cured top layer, by translating the puddle in the X direction on the cured top layer.
  • the heat curable mixture of this method comprises uncured PDMS.
  • the heat curable mixture may comprise a weight percent of PDMS and a weight percent of hardener totaling 100 weight percent.
  • the heat curable mixture used in the method will transmit at least 90% of an energy at each wavelength per micron of heat curable mixture in a wavelength range of 280 to 395 nanometers.
  • the method further uses a knife-edged blade having an edge apex thickness of less than 500 micrometers or less than 200 micrometers.
  • the re-coater blade is at a tilt angle of less than 90 degrees or in a range of 15 to 85 degrees, or in a range of 40 to 50 degrees.
  • a microfluidic device comprising a plurality of layers of a cured PDMS, a lower channel section having a lower channel, with the lower channel having at least a first lower channel port and a second lower channel port, an upper channel section located above the lower channel section having an upper channel, with the upper channel having at least a first upper channel port and a second upper channel port, wherein at least portion of the upper channel crosses over the lower channel with a membrane separating the upper channel and lower channel, and each of the first upper channel port, the second upper channel port, the first lower channel port and the second lower channel port have an electrode formed with the cured PDMS and connected with the first channel or the second channel is also disclosed.
  • This microfluidic device will have at least one electrode is at a bottom of a port.
  • At least one electrode may comprise Indium Tin Oxide (ITO). These electrodes may be attached to contact pads.
  • ITO Indium Tin Oxide
  • the microfluidic device can transmit at least 90% of an energy at each wavelength per micron of the microfluidic device in a wavelength range of 280 to 395 nanometers.
  • the upper channel and/or the lower channel can have at least one dimension less than 150 micrometers in the Z direction, the X direction or the Y direction.
  • FIG. 1 is a perspective view of a cured multi-layered PDMS microfluidic device with a channel made by this process.
  • FIG. 2 is a 3 dimensional view of a cured multi-layered PDMS microfluidic device made according to the invented method.
  • FIG. 3 A is a cured multi-layered PDMS device made according to this invention.
  • FIG. 3B is a cross-sectional view of a cured multi-layered PDMS device made according to this invention.
  • FIG. 4 is a top view of a cured multi-layered PDMS device made according to this invention and measurements of its internal features.
  • FIG. 5 is a side view of the system used to practice the invention.
  • FIG. 6A is a side view of the re-coater assembly.
  • FIG. 6B is a perspective view of the re-coater assembly.
  • FIG. 6C is a schematic side view of the invented re-coater.
  • FIG. 7A is a side view of the re-coater blade starting to form a layer of uncured PDMS.
  • FIG. 7B is a side view of the re-coater blade after forming the first layer of uncured PDMS.
  • FIG. 8A is a side view of the re-coater blade starting to form a layer of uncured PDMS when the height of the part is greater than the height of the PDMS puddle.
  • FIG. 8B is a side view of the re-coater blade just prior to forming a layer of uncured PDMS on top of a part whose height in the Z direction is greater than the height of the uncured PDMS puddle.
  • FIG. 8C is a side view of the re-coater lifting the uncured PDMS puddle to the top layer of the part when the height of the part is greater than the height of the uncured PDMS puddle.
  • FIG. 8D is a side view of the re-coater blade starting to thin the puddle of uncured PDMS on the top layer of the part and form the next layer.
  • FIG. 8E is a side view of the re-coater blade and slide stage after forming the layer of uncured PDMS.
  • FIG. 9 is a graph of the relative transmittance of light per micrometer of uncured PDMS.
  • the method and devices disclosed herein are based upon the research done attempting to print a microfluidic part by sequentially heat curing layers of PDMS (polydimethylsiloxane) and a hardener without the use of electromagnetic radiation absorbers such as UV activators or other curing agents.
  • PDMS polydimethylsiloxane
  • Sylgard 184 available from DOW Chemical, Midland, Michigan, USA.
  • the original project started out trying to find a laser to cut cured PDMS into a shape.
  • a laser having a 10.6 micrometer wavelength was evaluated and it was incapable of cutting the cured PDMS. It appeared as if the glass slide upon which the part was located was locally shattering.
  • a 1 .2 micrometer laser was evaluated. It showed slightly better results, but the slide still seemed to heat before the cured PDMS.
  • a 9.3 micrometer laser was evaluated and the ability to cut the cured PDMS was demonstrated. Seeing the ability to cut the cured PDMS led to the thought that the 9.3 micrometer wavelength laser might work for curing the uncured PDMS as well.
  • Both lasers were CO2 lasers.
  • transmittance per micrometer of the heat curable mixture became a control parameter in selecting the wavelengths of the energy source and the associated power.
  • the energy source applied to the part is not limited to a single wavelength source but could be a range of wavelengths or perhaps two or more discrete wavelengths striking the surface, just so long as the heat curable mixture has a transmission of at least one of the incident wavelengths per micrometer of less than 40%. It is preferred that the transmission of the incident wavelength per micrometer of the heat curable mixture be less than 55%, with less than 50% being more preferred, with less than 45% being even more preferred, with less than 40% being even more preferred with less than 35% being most preferred.
  • the cured part or the heat curable mixture absorbs more than 60% of the energy of at least one of the incident wavelengths per micrometer of the respective cured part or heat curable mixture. It is believed that the absorption at that wavelength per micrometer of the heat curable mixture or cured part should be more than 45%, with more than 50% being more preferred, with more than 55% being even more preferred, with more than 60% being even more preferred with more than 65% being most preferred.
  • Another wavelength range of electromagnetic radiation in which to cure the heat curable mixture is the UVC range which is in the range of 190nm to less than 280nm, more preferably 190nm to 275nm, and even more preferably 190nm to 250nm or 190nm to 235nm.
  • the PDMS of this invention can now be free, or void, of added UV absorber(s), heat up additives, or other agents overcoming the inherent difficulties of current curing techniques.
  • the heat curable mixture can be considered to have an amount of PDMS and an amount of hardener, which on a weight basis add up to 100 weight percent of the heat curable mixture.
  • the hardener could itself be a mixture blended with the PDMS.
  • the heat curable mixture should be void of any substance that does not play a role in the curing or hardening of the PDMS.
  • the heat curable mixture can have a transmission per micrometer of greater than 90% in the UVA and UVB spectrum (280nm to 395nm).
  • the cured PDMS in the part can also have a transmission per micrometer greater than 50% in the UVA and UVB spectra, with 60% more preferred, 75% even more preferred and 90% most preferred.
  • the cured part or the heat curable mixture absorbs less than 50% of the energy of at least one of the incident wavelengths per micrometer of the respective cured part or heat curable mixture. It is believed that the absorption at that wavelength per micrometer of the heat curable mixture or cured part should be less than 50%, with less than 40% being more preferred, with less than 25% being even more preferred, with less than 10% being even more preferred.
  • the energy source (laser) is then turned on to cure at least a portion of the layer.
  • the spot is scanned over the surface of the image for the appropriate amount of time.
  • the focus spot in these experiments was 80 micrometers.
  • the energy is directed only to those portions that are to be cured, it is not directed to those portions which are to remain uncured, such as the inside of a channel. The uncured portion is washed away from the part later.
  • the initial layers forming the base layer had to be at least 100 micrometers thick before building the part. It was discovered that the part would not stay adhered to the glass stage if the base layer comprised of multiple layers was less than 100 micrometers thick.
  • the build stage is the component upon which the part is to be built.
  • the apparatus stage is the component of the device which is acted upon to translate the part. This is because there is nothing else on the apparatus. In most cases, a glass slide will be placed upon the apparatus stage with the slide being the build stage, or glass stage.
  • the layered PDMS article is created by curing a PDMS base layer, L(0) onto the build stage. Another layer of heat curable mixture is formed on top of the previous cured layer, and then cured. Thus, the name “layer-by-layer” building.
  • the current layer being spread and subsequently cured is the current layer L(n).
  • the layer immediately previous to the current layer is L(n- 1).
  • the first layer in contact with the build stage is layer L(0).
  • Each layer “n” will have a layer thickness, which is denoted T(n).
  • FIGURE 5 of Riahi depicts a rotating paddle, or rotating blade, which pulls the heat curable material from the vat over the surface of the part after the build stage is lowered into the vat.
  • the part is lowered into the liquid uncured PDMS so that the level of the PDMS is at, or slightly higher than the top cured layer (n).
  • the re-coater than swipes a portion of the liquid PDMS to place a layer (n) of uncured PDMS across the top cured layer, which is now layer (n-1).
  • FIGS. 6A, 6B, and 6C The vat-less assembly used in this process is shown in FIGS. 6A, 6B, and 6C and described in detail below.
  • an amount of heat curable mixture is placed upon a horizontal (X-Y) stage.
  • the amount is preferably less than the amount that will flow on its own accord or that will flow across the build stage as the mass is greater than the surface tension of the mixture.
  • the heat curable mixture is placed upon the build stage and referred to as a puddle, although it may also be called a drop or bead.
  • the heat curable substance can be deposited on the top of the part itself and then thinned across the top to form the current layer.
  • This amount of heat curable mixture is then spread into a thin layer of thickness T(n), which in this case was as small as 7 micrometers.
  • the build stage and/or the re-coater are indexed in the Z direction for placement of the next amount of uncured PDMS.
  • the part is washed after the multi-layered part is built with the specified areas cured.
  • the wash removes the uncured PDMS from the part, such as the uncured portions in the channels such as those shown in FIGS. 1 to 4.
  • the equipment used in these experiments had a vertical translation stage and a stepper to raise or lower the stage under 1 micrometer, allowing the achievement of layers of less than 1 micrometer thick. This is the stage/slide platform in FIG. 5, and the stage in FIG. 6 A and 6B.
  • FIG. 5 also shows the dispensing syringe and laser window.
  • microfluidic PDMS devices in this specification were constructed layer- by- layer, on a plasma activated microscope slide (the build stage), through successive laser curing of thin layers of liquid PDMS to the previous device layer.
  • the components are shown in FIGS. 5, 6A and 6B.
  • Liquid PDMS premixed with the curing agent is dispensed by the translating PDMS syringe pump on the slide (stage) and the tilted-knife-re-coater (knife blade) distributes uniform layers of liquid PDMS over the previous layer with 7 micrometers being a typical layer thickness (T).
  • a Keyence MLZ 9650-T 9.3 micrometer CO2 laser lithography unit was used to selectively cure the PDMS.
  • the system has negative defocusing of the laser so that the focal point of the laser can be inside the layer or article.
  • Exemplary process parameters were laser power 5-6W, scan speed of 1 m/s, scan spacing 5 micrometer and defocusing distance of -2mm. These operating parameters and how to manipulate them are well known in the art.
  • the tilt angle (FIG. 7A) of the tilted knife-edge applies a downward force on the top of the puddle during translation and minimizes edge peeling because the recoater blade has a sharp trailing edge. As the puddle is only translated in one direction there is no opportunity for the uncured PDMS to adhere to the back of the re-coater blade.
  • the re-coater blade was then translated towards the part in the X axis creating the top layer, L(n), which is then cured. Once started across the slide, the puddle would create a wave like form up the re-coater blade and flow across the re-coater blade width (Y direction) as the puddle was pulled across the slide to the part.
  • FIG. 7A there is a gap between the end of the re-coater blade (the tip) and the build slide equal to the thickness of layer.
  • the gap equals T(0) (FIG. 7A).
  • Subsequent gaps are the thickness of the next layer to be placed T(n+1) (FIG. 8A).
  • the re-coater blade of the invented process was a steel razor blade with a precision edge which means that the re-coater blade edge is sharper than other razor blades for fine, precise cuts.
  • the blade used was an American Line (American Safety Razor Company, Verona, VA, USA) blade part No. 66- 0362 (Accutec Pro Extra Keen Single Edge Blade), 0.009’70.2286mm.
  • Teflon® coated blade did display some of the PDMS puddle seeping under the bleed and squeezing out the side opposite the part.
  • edge apex thickness The sharpness of a blade is well known in the art and is measured by edge apex thickness.
  • the edge apex radius is half the value of the of edge apex thickness. For example, a 50nm apex radius, which is lOOnm or 0.1 micron edge apex thickness.
  • Wickedly sharp is a preferred sharpness which is less than an edge apex thickness of less 0.3 micron. More preferable is Crazy sharp which is an edge apex thickness of less than 0.2 micron. Insane sharp will cut a free hanging hair and is preferable in the range of 0.1 to 0.15 micron. Razor sharp which splits hair are those edge apex thicknesses less than or equal to 0.1 micron. A blade sharper than Razor sharp, which can shave hair being most preferred and the edge apex thickness is less than 0.05 micron.
  • the edge apex thickness be in a range selected from the group consisting of greater than 0.10 micron to less than 0.5 micron, to less than 0.3 micron, to less than 0.2 micron, to less than 0.15 micron. Other limits are, less than or equal to 0.1 micron and less than 0.05 micron.
  • the tilted knife edge re-coater having an edge apex thickness will be at a tilt angle relative to the plane formed by the X-Y axis.
  • the X-Y axis should be parallel with the build stage plane and perpendicular to the Z axis.
  • the tilt angle, 0, is the angle formed by a line bisecting the blade and intersecting an X-Y plane in the -Z direction from the blade.
  • the tilt angle is less than 90 degrees.
  • the re-coater blade is at a tilt angle of approximately 45 degrees.
  • the tilt angle in the range of 15 to 85 degrees is also conceived, or 45 degrees +/-15 degrees is also preferred.
  • the conformal re-coating process begins with placing a puddle of a heat curable mixture of PDMS on the build stage between the part and the re-coater blade in the X direction.
  • FIG. 8A there are “ramps” of uncured PDMS (area with dots) on either side of the part.
  • the ramp on the right side of the part is what is left over after the layer portion of the uncured PDMS is separated from the puddle.
  • the ramp on the left is the excess uncured PDMS that flows down the side of the part after the layer is formed.
  • the puddle height is less than the cured part height.
  • the puddle of curable PDMS is translated along the X axis towards the part with the force from the re-coater spreading the puddle across the recoater blade (Y axis) and pushing the puddle up the re-coater blade (Z axis) from the slide.
  • the translating puddle approaches the part and is then forced up against the part and up the re-coated blade (FIG. 8B). This can be done by moving the re-coater blade, the build stage or both.
  • the puddle is then translated in the +Z direction, i.e. lifted above the top layer of the part.
  • This can be done by raising the re-coater blade in the +Z direction or lowering the build stage in the -Z direction, moving both, until the distance between the build stage to the re-coater blade end its tip equals the sum of the cured thicknesses (height of the cured part in the Z direction) plus the thickness of the next layer, L(n+1), of heat curable PDMS to be layered on top of part.
  • the re-coater blade is translated to a height in the Z direction where the distance between the end of the re-coater blade at its tip and the slide equals the height of the cured PDMS part from the build slide along the Z axis, plus the thickness of the layer of heat curable PDMS to be placed on the part.
  • This distance between the top layer and the slide is the thickness (T(n+1) of the layer to be formed (L(n+1) as shown in FIG. 8C.
  • the puddle is then translated in the X direction across the cured top layer of the part (FIG. 8D, L(n)) forming a layer of heat curable PDMS (L(n+1)). Again, this translation can be done moving the re-coater blade or the build stage, or both.
  • the layer becomes new layer L(n).
  • the new layer is uncured, as evidenced by the dashed line and dots.
  • the cured layer, shown with no dots, previously known as L(n) will become layer L(n-l) once the heat curable layer is cured. Layer “n” does not become layer n-1 until layer “n+1” is cured.
  • the speed of the re-coater blade at this point is typically less than the speed of the re-coater blade passing over the slide.
  • the re-coater blade moved across the top of the part at a speed of 2mm/sec. Care is taken to not move too fast as it will create wavy layers.
  • the dashed line represents the new uncured layer, L(n) which has been translated onto the last cured layer, L(n-l).
  • Typical ranges for a layer of this invention are 5 micrometers to 200 micrometers, 5 micrometers to 150 micrometers, 5 micrometers to 100 micrometers, and 5 micrometers to 50 micrometers.
  • the article comprises at least one layer having a thickness selected from the group consisting of 5 micrometers to 200 micrometers, 5 micrometers to 150 micrometers, 5 micrometers to 100 micrometers, and 5 micrometers to 50 micrometers.
  • the viscosity of the PDMS curable mixture is selected to enable the elimination of the PDMS vat using a conformal recoating technique where the re-coater blade follows the approximate upper-Z boundary of the X-Y profile of the build slide and the part moving the liquid up the side and the re-coating the top layer of article at each layer.
  • FIGS 3A, 3B and 4 show various views of a microfluidic device made by the teachings of this specification.
  • the cured microfluidic device may be built upon a slide, typically a glass slide, which is the build stage.
  • FIGS 3A, 3B, and 4 the lines of the individual build layers are not shown, and the microfluidic device is described in sections. While the Figures show the microfluidic device in sections, the section is made up of individual layers with at least some of them having thicknesses in the ranges disclosed in this specification.
  • Each channel has two ports, one at each end. There is a first upper channel port associated with electrode Al , and a second upper channel port associated with electrode A2. There is a first lower channel port associated with electrode B 1 and a second lower channel port associated with electrode B2. Each port is shown as a hollow cylinder with the port being open at the top of the microfluidic device and running to the respective electrode.
  • Electrodes Al, A2, Bl and B2 are indium tin oxide (ITO). They rest on the slide. They are placed there by affixing a layer of ITO on the slide and then ablating away the unwanted portions leaving the electrode. The microfluidic device is then built upon the slide.
  • ITO indium tin oxide
  • the electrode is attached to an ITO contact pad where the current is provided.
  • each electrode is located under the cured microfluidic device at the bottom of the respective port which is the open vertical cylinder directly above the electrode.
  • This device can be used to test and monitor many items.
  • the membrane used was to simulate the blood brain barrier (BBB), hence the name BBB MF (Blood Brain Barrier Microfluidic).
  • the placement of the electrode at the bottom of the port ensures constant and the same contact area.
  • This device can be used to measure the properties of the barrier, such as conductivity.
  • this device could have channels with sides measuring any of the previously disclosed ranges, in particular sides in the range of 5 micron to 150 micron.
  • typical ranges for a layer of these processes and the layers of the devices described above are 5 micrometers to 200 micrometers, 5 micrometers to 150 micrometers, 5 micrometers to 100 micrometers, and 5 micrometers to 50 micrometers.
  • the article comprises at least one layer having a thickness selected from the group consisting of 5 micrometers to 200 micrometers, 5 micrometers to 150 micrometers, 5 micrometers to 100 micrometers, and 5 micrometers to 50 micrometers.

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Abstract

L'invention concerne des procédés et des dispositifs pour construire des polymères thermodurcissables durcis 3-D à l'aide de lasers. Ces dispositifs ne nécessitent aucun additif UV et peuvent être fabriqués sans utiliser de cuve ni de techniques d'enduction centrifuge. Le procédé repose sur l'utilisation d'une lame aiguisée inclinée employée comme réenducteur et sur la translation du matériau non durci dans la direction Z pour des pièces relativement hautes.
PCT/US2023/073060 2022-09-03 2023-08-29 Fabrication additive de polymères thermodurcissables par durcissement laser thermique WO2024050344A1 (fr)

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US202263374538P 2022-09-03 2022-09-03
US63/374,538 2022-09-03
USPCT/US2023/065371 2023-04-05
PCT/US2023/065371 WO2023196848A1 (fr) 2022-04-05 2023-04-05 Multi-organe imprimé en 3d sur une puce

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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2001284700B2 (en) * 2000-08-03 2005-12-08 Caliper Life Sciences, Inc. Methods and devices for high throughput fluid delivery
JP2012211914A (ja) * 2000-04-06 2012-11-01 Caliper Life Sciences Inc 保護層を組み込んだミクロ流体装置及びシステム
CN107115897A (zh) * 2016-02-25 2017-09-01 中国科学院苏州纳米技术与纳米仿生研究所 微流控芯片及其制作方法
US20190234961A1 (en) * 2018-01-29 2019-08-01 Intabio, Inc. Devices, methods and kits for sample characterization
US20200016592A1 (en) * 2018-06-25 2020-01-16 Nemametrix Inc. High-throughput microfluidic-based methods for recording defecation motor program (dmp) events in nematodes
US20200030879A1 (en) 2017-02-16 2020-01-30 Arizona Board Of Regents On Behalf Of The University Of Arizona Laser-assisted additive manufacture of optics using thermally curable materials
US20210214670A1 (en) * 2015-12-04 2021-07-15 EMULATE, Inc. Open-top microfluidic device with structural anchors
US20220088872A1 (en) * 2019-01-14 2022-03-24 Arizona Board Of Regents On Behalf Of The University Of Arizona High resolution, high throughput additive manufacturing
EP3625056B1 (fr) * 2017-05-15 2022-04-13 Holo, Inc. Systèmes et procédés d'impression tridimensionnelle de film visqueux

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012211914A (ja) * 2000-04-06 2012-11-01 Caliper Life Sciences Inc 保護層を組み込んだミクロ流体装置及びシステム
AU2001284700B2 (en) * 2000-08-03 2005-12-08 Caliper Life Sciences, Inc. Methods and devices for high throughput fluid delivery
US20210214670A1 (en) * 2015-12-04 2021-07-15 EMULATE, Inc. Open-top microfluidic device with structural anchors
CN107115897A (zh) * 2016-02-25 2017-09-01 中国科学院苏州纳米技术与纳米仿生研究所 微流控芯片及其制作方法
US20200030879A1 (en) 2017-02-16 2020-01-30 Arizona Board Of Regents On Behalf Of The University Of Arizona Laser-assisted additive manufacture of optics using thermally curable materials
EP3625056B1 (fr) * 2017-05-15 2022-04-13 Holo, Inc. Systèmes et procédés d'impression tridimensionnelle de film visqueux
US20190234961A1 (en) * 2018-01-29 2019-08-01 Intabio, Inc. Devices, methods and kits for sample characterization
US20200016592A1 (en) * 2018-06-25 2020-01-16 Nemametrix Inc. High-throughput microfluidic-based methods for recording defecation motor program (dmp) events in nematodes
US20220088872A1 (en) * 2019-01-14 2022-03-24 Arizona Board Of Regents On Behalf Of The University Of Arizona High resolution, high throughput additive manufacturing

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
POULIN JÉROME: "M'EMOIRE PR'ESENT'E EN VUE DE L'OBTENTION DU DIPL? OME DE MA?ITRISE `ES SCIENCES APPLIQU'EES", 22 May 2014 (2014-05-22), pages 1 - 158, XP093118149, Retrieved from the Internet <URL:https://www.researchgate.net/publication/233866465_Etude_des_proprietes_optiques_et_mecaniques_du_polydimethylsiloxane_sous_radiation_ultraviolette_pour_l'ecriture_de_reseaux_de_Bragg_et_la_fabrication_de_microstructures_photoniques_accordables/download?_tp=eyJjb250ZXh0Ijp7ImZpcnN0UGFnZSI6Il9kaXJlY3> [retrieved on 20240111] *
RIAHI RIAHI MOHAMMADREZA MOHAMMADREZA ET AL: "Fabrication of 3D microfluidic structure with direct selective laser baking of PDMS", vol. 25, no. 4, 12 July 2019 (2019-07-12), GB, pages 775 - 780, XP093061192, ISSN: 1355-2546, Retrieved from the Internet <URL:https://www.emerald.com/insight/content/doi/10.1108/RPJ-01-2018-0021/full/pdf?title=fabrication-of-3d-microfluidic-structure-with-direct-selective-laser-baking-of-pdms> [retrieved on 20230705], DOI: 10.1108/RPJ-01-2018-0021 *

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