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WO2018055609A1 - Procédé et appareil pour la fabrication d'objets 3d - Google Patents

Procédé et appareil pour la fabrication d'objets 3d Download PDF

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Publication number
WO2018055609A1
WO2018055609A1 PCT/IL2017/050953 IL2017050953W WO2018055609A1 WO 2018055609 A1 WO2018055609 A1 WO 2018055609A1 IL 2017050953 W IL2017050953 W IL 2017050953W WO 2018055609 A1 WO2018055609 A1 WO 2018055609A1
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WIPO (PCT)
Prior art keywords
pseudoplastic material
pseudoplastic
extruded
viscosity
material according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/IL2017/050953
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English (en)
Inventor
Nataly Lisitsin
Victoria Gordon
Igor Yakubov
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Massivit 3D Printing Technologies Ltd
Original Assignee
Massivit 3D Printing Technologies Ltd
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Filing date
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Publication of WO2018055609A1 publication Critical patent/WO2018055609A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • 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
    • B29C64/118—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using filamentary material being melted, e.g. fused deposition modelling [FDM]
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/92—Measuring, controlling or regulating
    • 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
    • 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
    • B33Y70/00—Materials specially adapted for additive manufacturing
    • B33Y70/10—Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/34—Silicon-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/04—Oxygen-containing compounds
    • C08K5/05—Alcohols; Metal alcoholates
    • C08K5/053—Polyhydroxylic alcohols
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/04—Oxygen-containing compounds
    • C08K5/15—Heterocyclic compounds having oxygen in the ring
    • C08K5/151—Heterocyclic compounds having oxygen in the ring having one oxygen atom in the ring
    • C08K5/1525—Four-membered rings
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/49—Phosphorus-containing compounds
    • C08K5/51—Phosphorus bound to oxygen
    • C08K5/52—Phosphorus bound to oxygen only
    • C08K5/521—Esters of phosphoric acids, e.g. of H3PO4
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K7/00—Use of ingredients characterised by shape
    • C08K7/02—Fibres or whiskers
    • 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
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
    • B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
    • B29C2035/0822—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using IR radiation
    • 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
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
    • B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
    • B29C2035/0827—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using UV radiation
    • 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
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
    • B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
    • B29C2035/0833—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using actinic light
    • 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
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
    • B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
    • B29C2035/0855—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using microwave
    • 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
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/02—Small extruding apparatus, e.g. handheld, toy or laboratory extruders
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/022—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/15—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor incorporating preformed parts or layers, e.g. extrusion moulding around inserts
    • B29C48/154—Coating solid articles, i.e. non-hollow articles

Definitions

  • the present disclosure is concerned with a method of additive
  • Three dimensional objects manufacturing processes include deposition of a resin layer, imaging of the layer and curing or hardening of the imaged segments of the layer.
  • the layers are deposited (added) on top of each other and hence the process is called additive manufacturing process by means of which a computer generated 3D model is converted into a physical object.
  • the process involves generation of a plurality of material layers of different or identical shape. The layers are laid down or deposited on top (or bottom) of each of the preceding layer until the amount of layers results in a desired three dimensional physical object.
  • the material from which the layers of the three-dimensional physical object are generated could come in liquid, paste, powder, gel and other forms. Conversion of such materials into a solid form is typically performed by suitable actinic radiation or heat.
  • the deposited material layers are thin twenty to forty micron layers. Printing or manufacture of a three-dimensional object is a relatively long process. For example, manufacture of a 100x100x100 mm3 cube would require deposition of 4000 of layers.
  • Such thin layers are mechanically not strong and when a cantilever object or a hollow three- dimensional object has to be printed or manufactured there is a need to introduce different structural support elements that would maintain the desired strength of the printed three-dimensional object.
  • the time required to build a three-dimensional object depends on various parameters, including the speed of adding a layer to the three- dimensional object and other parameters such as for example, curing time of resin using ultra-violet (UV) radiation, the speed of adding solid or liquid material to the layer which depends on the material itself, layer thickness, the intensity of the curing agent and the desired resolution of the three-dimensional object details.
  • parameters including the speed of adding a layer to the three- dimensional object and other parameters such as for example, curing time of resin using ultra-violet (UV) radiation, the speed of adding solid or liquid material to the layer which depends on the material itself, layer thickness, the intensity of the curing agent and the desired resolution of the three-dimensional object details.
  • UV ultra-violet
  • United States Patent No. 9,216,543 to the same inventor and assignee and included herein by reference discloses a radical curable high viscosity (40000 to 400000 m Pa- sec.) gel material from which large 3D objects are build.
  • WO2008/015474 to Owen disclose ink jet inks cured by a cationic curing mechanism.
  • the inks are of low viscosity that in some cases is as low as 5.0 cps. (1 .0 millipascal x second is equal to 1 .0 centipoise.)
  • a substance for example a fluid or gel or paste
  • a mechanical force such as shear or pressure.
  • the applied force can be agitating, stirring, pumping, shaking or another mechanical force.
  • Many gels are pseudoplastic materials, exhibiting a stable form at rest but become fluid when agitated or pressure is applied to them. Some pseudoplastic fluids return to a gel state almost instantly, when the agitation is discontinued.
  • gel when used in the present application refers to a composition comprising a crosslinked system and a fluid or gas dispersed therein, which composition exhibits no or substantially no flow when in the steady-state.
  • the gel becomes fluid when a force is applied, for example when the gel is pumped, stirred, or shaken, and resolidifies when resting, i.e. when no force is applied.
  • This phenomen includes also thixotropy.
  • the major part of a gel is liquid, such as up to more than 99 %, gels behave like solids due to the three- dimensional network.
  • cantilever as used in the present disclosure means a structure resting on a single support vs. a bridge having two supports. Typically, cantilever support is located at one of the ends of the cantilever.
  • cantilever ratio means a ratio of the extruded pseudoplastic material cross section to the length of unsupported material.
  • strip and "portion” are both used for a part of pseudoplastic material that has been extruded. Both terms are used exchangeably.
  • image refers to a layer of a product produced in one cycle of extrusion, i.e. a layer that is printed in one step by movement of the extrusion unit.
  • curable monomer refers to a compound having at least one reactive group that can react with other reactive groups, for example with other monomers, with oligomers or reactive diluents, or can be oligomerized or polymerized, in particular when radiated with suitable radiation.
  • monomers are acryl based monomers, epoxides and monomers forming polyesters, polyethers and urethanes.
  • ethylenically unsaturated monomer refers to monomers that have unsaturated groups that can form radicals when radiated with suitable radiation.
  • the monomers have at least one unsaturated group, such as an ⁇ , ⁇ -ethylenically unsaturated group or a conjugated unsaturated system, such as a Michael system.
  • actinic radiation refers to electromagnetic radiation that can produce photochemical reactions.
  • curing or "photocuring” refers to a reaction of monomers
  • oligomers to actinic radiation, such as ultraviolet, heat or other radiation, whereby reactive species are produced that promote cross-linking and curing of monomers or oligomers, particularly cross-linking and curing of unsaturated groups.
  • the curing mechanism produced by a curing reaction could be radical, cationic or their combination.
  • the current application discloses use of radical, cationic and hybrid curing materials and methods.
  • cationic curing relates to a type of chain growth polymerization in which a cationic initiator transfers charge to a monomer which then becomes reactive. This reactive monomer goes on to react similarly with other monomers to form a harden polymer.
  • Cationic curing mechanism involves protonic acid generation which for example, initiates ring opening polymerization of epoxy resins.
  • the term "radical curing” relates to a type of curing where a free radical mechanism of radiation curable material includes a photoinitiator that absorbs curing radiation and generates free-radicals.
  • the free radicals induce cross- linking reactions of a material that includes oligomers and monomers to generate a harden material or polymer. Radical curing mechanism promotes chain polymerization of for example, acrylate type monomers/oligomers.
  • hybrid curing relates to a type of curing employing dual
  • Hybrid curing material chemistries could be a mix of different percentages of cationic and free-radical chemistries.
  • reaction that crosslinks or otherwise reacts oligomers and/or reactive diluent in particular it refers to the reaction between oligomers and reactive diluent resulting in a crosslinked material.
  • oligomer refers to polymerized monomers having 3 to 100, such as 5 to 50, or 5 to 20 monomer units.
  • “Curable oligomers” that are used in the present disclosure are oligomers having functional groups that can be cured or cross-linked by activation such as by radiation.
  • reactive diluent refers to a compound that provides at least one, such as 1 , 2, 3, or more functional groups that can react with a curable monomer or oligomer.
  • a reactive diluent can comprise reactive groups like hydroxy groups, ethylenically unsaturated groups, epoxy groups, amino groups, mono, di and tetra functional reactive acrylate diluents or a combination thereof.
  • a reactive diluent can comprise one or more hydroxy groups and one or more amino groups, ethylenically unsaturated groups etc.
  • Examples of reactive diluents include monofunctional and polyfunctional compounds, such as monomers containing a vinyl, acryl, acrylate, acrylamide, hydroxyl group among others.
  • a reactive diluent typically is a mono-, di- or trifunctional monomer or oligomer having a low molecular weight. Typical examples are acrylate and methacrylate esters including mono-, di-, and tri-(meth)acrylates and -acrylates or oxitanes.
  • a cross-linking component should provide at least two curable terminal groups.
  • the "cross-linking component” can comprise one or more reactive diluents and further di-, tri- or multifunctional compounds, if necessary.
  • a "photoinitator” is a chemical compound that decomposes into free
  • radicals when exposed to light are among the group of aromatic a-keto carboxylic acid and their esters, a-aminoalkyl phenone derivatives, phosphine oxide derivatives, benzophenones and their derivatives and other photocuring compounds that are well-known in the art.
  • Suitable cationic curing photoinitiators are among the group of the onium salts as sulfonium, iodonium or diazonium salts.
  • rheology modifier refers to components that control viscosity and/or can have a thickening action, or are suspending or gelling agents, preventing sedimentation.
  • Rheology modifiers that are useful for the present disclosure comprise organic and anorganic rheology modifiers and associative as well as non-associative modifiers.
  • Organic rheology modifiers comprise products based on natural materials, like cellulose, cellulose derivatives, alginates, or polysaccharides and their derivatives, like xanthan, or synthetic polymeric materials like polyacrylates, polyurethanes or polyamides.
  • Anorganic rheology modifiers comprise clays, like bentonite clays, attapulgite clays, organoclays, kaolin, and treated or untreated synthetic silicas, like fumed silicas. Inorganic rheology modifiers tend to have high yield values and are characterized as thixotropes.
  • non-associative rheology modifier comprises modifiers that act via entanglements of soluble, high molecular weight polymer chains
  • hydrodynamic thickening The effectiveness of a non-associative thickener is mainly controlled by the molecular weight of the polymer.
  • the term "associative rheology modifiers” refers to substances that thicken by non- specific interactions of hydrophobic end-groups of a thickener molecule both with themselves and with components of the coating. They form a so called “physical network”.
  • Viscosity refers to dynamic viscosity. It is measured using a rheometer, in particular a shear rheometer such as one with a rotational cylinder or with cone and plate, at room temperature, i.e. at 25°C or a viscosimeter such as for example, Brookfield DV-E viscometer.
  • extruusion unit refers to any unit that is capable of
  • An extrusion unit includes at least one screw and at least one discharge port such as an extrusion head, extrusion nozzle, extrusion die or any other type of extrusion outlet.
  • extrusion nozzle, extrusion die and extrusion head can be used interchangeably.
  • the current three-dimensional object manufacturing technique relies on the deposition of a pseudoplastic material in gel aggregate state.
  • a gel is provided that flows through a deposition nozzle because of the applied agitation and the gel's elasticity recovers immediately after leaving the nozzle, and the gel solidifies to maintain or regain its shape and strength.
  • shear stress generated by agitation breaks the three-dimensional network bonds within the liquid. After leaving the nozzle the material is no longer under stress and the network recovers immediately after leaving the nozzle, resulting in the gel resolidifying.
  • the process allows to produce objects that have structures that are difficult to build without supporting structures such as cantilever- like objects.
  • the pseudoplastic material used in the process is cured or hardend by radical, or cationic curing techniques.
  • the pseudoplastic material used in the process is a mixture of radical and cationic chemistries.
  • the pseudoplastic material includes different additives that improve finished product properties.
  • FIG. 1 is a schematic illustration of an example of an apparatus for
  • FIGS.2A and 2B are examples of a three-dimensional object
  • FIGS. 3A - 3C are illustrations explaining printing or manufacture of a
  • FIG. 4 is an example of a hollow rectangular prism with 90 degrees
  • FIG. 5 is a graph that demonstrates the variations of viscosity vs shear rate.
  • the disclosure will be described with reference to the attached non- limiting drawings.
  • the present disclosure is concerned with methods for the manufacture of three- dimensional structures by printing, i.e. by so-called 3D- printing, a material and an apparatus useful therefore, and the use of a pseudoplastic material for 3D printing.
  • pseudoplastic material i.e. a composition with decreasing viscosity when shear force is applied, allows to produce sophisticated and complex three-dimensional structures by 3D printing, in particular hollow structures and structures that are cantilever-like, without the need for supporting elements during manufacture.
  • the pseudoplastic material used according to the present disclosure shows shear- thinning in a range such that the starting composition having high viscosity when it is transferred to and through an extrusion unit has a viscosity low enough for the transfer and for creating a portion of a 3D structure, such as a strip, or a layer or an image, but has an increased viscosity within short term when it arrives at its predetermined position.
  • Viscosity of the starting composition is also called “first viscosity” and viscosity after application of a force, such as at the outlet of the extrusion unit, is also called “second viscosity”.
  • a gel which viscosity decreases to about 700-250 mPa-s at a pressure higher than atmospheric pressure.
  • a number of pseudoplastic material compositions that are useful for this purpose is as defined below. Some of the compositions or formulations are suitable for radical curing processes. Other of the compositions could be better cured by cationic curing processes and still other compositions are more suitable for hybrid curing processes.
  • One three-dimensional object manufacturing technique relies on the deposition of material in gel aggregate state.
  • the gel flows through a deposition nozzle because the applied agitation and pressure shears the inter-particle bonds and induces a breakdown in the elasticity of the material.
  • the material recovers immediately after leaving the nozzle, and the pseudoplastic material or gel almost immediately solidifies to maintain its shape.
  • a method of forming a three-dimensional object comprising:
  • step c obtaining a common contact section between the surfaces of the first and second extruded portions by forming an envelope into which a segment of the first portion protrudes by sliding, due to the gravitational force, of the second portion along the circumference of the surface of the first portion hardened in step c), wherein the surface of the second portion wets the surface of the first portion at the common contact section;
  • the present application also discloses a method of additive manufacture of a three- dimensional object which comprises the following steps:
  • the second portion of pseudoplastic material has at least one common contact section with the first portion of the pseudoplastic material
  • extrusion from the nozzle changes the viscosity to a viscosity substantially higher than the viscosity at the pressure exceeding atmospheric pressure.
  • a three-dimensional object can be obtained with any of the above mentioned methods and by use of any of the disclosed material formulations and the objects obtained are also part of the present disclosure.
  • An apparatus that is useful for manufacture of a three-dimensional object comprises a tank for storing a pseudoplastic material at atmospheric pressure; a pump configured to apply agitation to the pseudoplastic material to shear thin the pseudoplastic material and reduce the pseudoplastic material viscosity such as to cause the material to flow; an extrusion unit comprising an extrusion nozzle, an extrusion head, an extrusion die, or another extrusion outlet, configured to extrude in image-wise manner the pseudoplastic material at a pressure exceeding atmospheric pressure; and an X-Y-Z movement system configured to move at least the extrusion nozzle in a three coordinate system.
  • FIG. 1 is a schematic illustration of an example of an apparatus suitable for
  • the apparatus comprises at least a container such as a tank to receive the pseudoplastic material, a pump to apply a force to the pseudoplastic material, an extrusion unit comprising a nozzle to extrude the pseudoplastic material, and a movement system comprising a control unit, such as a computer.
  • a container such as a tank to receive the pseudoplastic material
  • a pump to apply a force to the pseudoplastic material
  • an extrusion unit comprising a nozzle to extrude the pseudoplastic material
  • a movement system comprising a control unit, such as a computer.
  • Apparatus 100 includes a container for pseudoplastic material, such as a storage or material supply tank 102 adapted to store a pseudoplastic high viscosity material 104, a pump 108 configured to apply a force to the gel, for example by agitating and shear thinning the pseudoplastic high viscosity material or gel 104, to reduce material 104 viscosity to cause the material to flow.
  • a container for pseudoplastic material such as a storage or material supply tank 102 adapted to store a pseudoplastic high viscosity material 104
  • a pump 108 configured to apply a force to the gel, for example by agitating and shear thinning the pseudoplastic high viscosity material or gel 104, to reduce material 104 viscosity to cause the material to flow.
  • Pumps for such purpose are well-known in the art and any pump that can apply shear to the gel to be extruded is useful.
  • Pump 108 could be such as Graco S20 supply system commercially available from Graco Minneapolis, MN U.S.A., or a barrel follower dispensing pump Series 90 commercially available from Scheugenpflug AG, 93333 Neustadt a.d. Donau, Germany. Pump 108 in addition to agitation also develops a pressure higher than atmospheric pressure such that the pseudoplastic material 104 flows through a delivery tubing or system 1 12 to an extrusion (unit) nozzle 1 16. The higher than atmospheric pressure developed by the pump is communicated to the dispenser and could be such as 0.1 bar to 30.0 bar and typically from 1 .0 bar to 20.0 bar and sometimes 2.0 bar to 10.0 bar.
  • Apparatus 100 includes an X-Y-Z movement system 124 configured to move the extrusion nozzle 1 16 in a three coordinate system.
  • a table 120 could be made to move in a three coordinate system.
  • the movement in three directions (X-Y-Z) could be divided between the extrusion nozzle 1 16 and table 120.
  • Apparatus 100 also includes a control unit, such as computer 128 configured to control operation of movement system 124, pump 108 pseudoplastic material steering operation and value or magnitude of the pressure higher than atmospheric pressure.
  • the control unit, computer 128 is further adapted to receive the three- dimensional object 132 data and generate from the received data the X-Y-Z movement commands and distance such that the pseudoplastic material 104 is extruded through extrusion unit 1 14 and nozzle 1 16 in an image wise manner.
  • the X- Y-Z movement could be performed in a vector mode or raster mode, depending on the object to be printed.
  • Computer 128 could also be configured to optimize the decision on the printing mode.
  • Apparatus 100 further includes a source of radiation for curing or
  • the source of radiation could provide ultraviolet radiation, infrared radiation, heat, microwave radiation and other types of radiation suitable for curing the material.
  • a UV LED based source of radiation 136 is used for curing the extruded material.
  • An example for a source of radiation 136 is a FireJet FJ200 commercially available from Phoseon Technology, Inc. , Hillsboro OR 97124 USA.
  • a suitable source of radiation 136 provides UV radiation with total UV power of up to 900W and with a wavelength that normally is in the range of 230- 420 nm, but can also be in the range of 360-485 nm, for example a wavelength in the range of 380-420 nm.
  • UV lamp such as for example, mercury vapor lamp model Shot 500 commercially available from CureUV, Inc., Delray Beach, FL 33445 USA can be used, or any other UV lamp that is available.
  • the source of UV radiation 136 operates in a continuous manner and the UV radiation is selected to harden the pseudoplastic material 104.
  • Computer 128 could also be configured to control operation of source of UV radiation 136 and synchronize it with the printing mode.
  • a highly viscous pseudoplastic material 104 such as the one that will be described below under test name BGA 0, is provided in tank 102.
  • the pseudoplastic material has a first viscosity or starting viscosity before the material is conveyed to the extruder unit. By application of shear the viscosity is reduced so that the material has a second viscosity which is in a range such that the material easily flows. After extrusion the material rests and regains at least a percentage of the first viscosity.
  • a suitable first or starting viscosity for the pseudoplastic material 104 could be in the range of about 40,000 to 500,000 mPa-s, and typically such as 100,000 to 400,000 mPa-s at a low shear rate. The viscosity after application of shear can decrease as low as 250 mPa-s.
  • Pump 108 is operative to agitate and deliver material 104 through the delivery system 1 12 to the extrusion unit 1 14 and to nozzle 1 16 and apply to it a varying pressure exceeding the atmospheric pressure.
  • the tested pseudoplastic material formulation has shown different degrees of shear thinning properties and viscosity under different pressure. The pressure applied would typically be in range of 1 .0 bar to 5.0 bar.
  • agitation and pressure to material 104 reduces the viscosity of material 104 by a shear thinning process to about 250 - 700 mPa-s and typically to about 450 to 550 mPa-s.
  • the pressure higher than atmospheric pressure applied to the pseudoplastic material with reduced viscosity is sufficient to shear the pseudoplastic material 104 and cause it to flow through a delivery system 1 12 to extrusion unit 1 14 to be extruded through nozzle 1 16.
  • Extrusion unit 1 14 or nozzle 1 16 extrudes a strip or a portion of the pseudoplastic material 104 in image-wise manner.
  • the system can comprise one extrusion unit or more than one unit and one unit can comprise one nozzle or more.
  • the diameter of a nozzle can have different forms as is known in the art.
  • Other than round nozzle 1 16 cross sections are possible and generally a set of exchangeable nozzles with different cross sections could be used with apparatus 100.
  • the control unit such as computer 128, is adapted to receive the three- dimensional object 132 data and generate from the received data the X- Y-Z movement commands and length of strips of pseudoplastic material 204-1 , 204-2 (FIG. 2B) and so on, such that the pseudoplastic material 104 extruded through extrusion (unit) nozzle 1 16 in an image wise manner resembles a slice of object 132.
  • pseudoplastic material 104 is extruded.
  • FIGS. 3A-3C are illustrations explaining printing or manufacture of a 3D object with the present pseudoplastic material or gel.
  • FIG. 3 B when producing horizontally oriented segments of a three-dimensional object, each next or adjacent strip or portion of pseudoplastic material 204-4 or 204-5 is extruded or printed.
  • Strip or drop 204-5 could slightly shift or slide in a direction indicated by arrow 312 at about the boundary 304 of the previously extruded strip or layer, for example 204-4 or 204-3.
  • the shift or slide 308 could be in a range of 1/5 to 1/35, such as 1/10 or 1/30 of the extruded strip diameter and the shift or slide value could vary in the process of the three-dimensional object manufacture.
  • Drop or strip 204-5 slides as shown by arrow 312 from its unstable position to a more stable position dictated by the solidification rate of the pseudoplastic material that could be attributed to the material viscosity increase and gravitational forces.
  • the cross-section of the second strip or drop 204-5 is shifted (304) in an axis perpendicular to the gravitational force compared to the cross-section of the first strip or drop 204-4.
  • drop or strip 204-5 wets the surface of the adjacent strip 204-4 and the still at least partially liquid drop or strip 204-5 is forming an envelope into which a segment of the previously printed drop or strip 204-4 protrudes.
  • the large contact surface between earlier printed drop/strip or layer and the later extruded drop/strip or layer contributes to extraordinary strength of the bond between the strips/drops or layers.
  • viscosity of the extruded drop/strip is rapidly increasing limiting to some extent the slide of the drop and further contributing to the bond strength.
  • Curing radiation sources 136 are operative in course of printing and by the time drop/strip 204-5 reaches its stable position drop/strip 204-5 solidifies or hardens. In some examples, a shift of a drop/strip can be intentionally introduced.
  • cantilever-like structures or three-dimensional objects with a cantilever ratio of at least 1 :5 and up to 1 :200 and even more without any conventional support structures.
  • Objects of FIGS. 2A and 2B have been printed by strips with diameter of 1 .3 mm.
  • Objects of FIGS. 2A and 2B had a cantilever ratio from 1 :5 up to more than 1 :200. No support structures have been required.
  • FIG. 3C illustrates manufacture or printing of a vertical segment of a 3D object.
  • drops 204 are positioned on top of each other and before the pseudoplastic material solidifies the later printed strip 204-5 wets the surface of the adjacent strip 204-4 and the still, at least partially liquid strip 204-5, is forming an envelope into which a segment of the previously printed strip 204-4 protrudes.
  • the present method and apparatus are useful for manufacturing hollow articles in a size not available until now without support structures. With the new system it is possible to prepare hollow figures of big size for example
  • FIG. 4 is an example of a hollow rectangular prism with 90 degrees angles.
  • the dimensions of prism 404 cross section are 150x150mm2.
  • the extruded strips 408 has a square cross section with dimensions of 1 .8x1 .8mm2. No internal support structures are required.
  • the source of radiation that is used according to the present disclosure can be operated in a continuous mode or a discontinuous mode.
  • the skilled person can choose the mode that is best suited for a specific object and material, respectively.
  • a continuous mode the source of radiation 136 irradiates the strips of the three-dimensional object 132 being manufactured to harden or cure the extruded layer of material 104.
  • extrusion unit 1 14 can continue to extrude layers of the pseudoplastic material in an image- wise manner and source of radiation 136 could operate to continuously illuminate or irradiate extruded layers of pseudoplastic material 104 to form a cured extruded layer of a three-dimensional object.
  • a discontinuous mode the source of radiation is adapted to irradiate the extruded layer of material when it is necessary.
  • the pseudoplastic material has a first viscosity at atmospheric
  • the second viscosity is lower than the first viscosity and as the material 104 is leaving the extrusion unit (nozzle) it immediately upon leaving the extrusion nozzle recovers a significant fraction of the first viscosity, such as at least 30 %, suitably at least 40 %, in particular at least 50 % of the first viscosity.
  • the recovered viscosity in a preferred embodiment is between 60 to 90% or even more of the first viscosity.
  • the radical curable pseudoplastic gel material used for the present 3D objects printing comprises at least one curable oligomer, at least one reactive diluent, at least one curing agent, at least one rheology modifier, and optionally at least one performance improving additive and/or further additives.
  • the cationic curable pseudoplastic gel material used for the present 3D objects printing comprises at least one epoxy or vinyl ether compound, at least one cationic curing agent, at least one rheology modifier, and optionally at least one performance improving additive and/or further additives.
  • the curable oligomers used in the present curable composition can be oligomers having at least one ethylenically unsaturated group and can be comprised for example of urethane, epoxy, ester and/or ether units. Oligomers such as acrylated and methacrylated oligomers such as acrylated epoxies, polyesters, polyethers and urethanes are useful.
  • oligomers useful in the present disclosure are acryl based or methacryl based oligomers, olefine based oligomers, vinyl based oligomers, styrene oligomers, vinyl alcohol oligomers, vinyl pyrrolidone oligomers, diene based oligomers, such as butadiene or pentadiene oligomers, addition polymerization type oligomers, such as oligoester acrylate based oligomers, for example oligoester (meth)acrylate or oligoester acrylate, polyisocyanate oligomers, polyether urethane acrylate or polyether urethane methacrylate oligomers, epoxy oligomers among others. Those oligomers are known in the art and are commercially available.
  • Epoxy resins that undergo cationic polymerization show lower shrinkage, insensitive to oxygen inhibition and undergo "dark reaction"- post cure effect, where areas that are not exposed to UV irradiation or thick layers can also be cured.
  • the printing material may further include an epoxide
  • a cationic reagent typically includes at least one cyclic ether group (e.g., one or more epoxide groups (e.g., a three member cyclic ether), (e.g., at least one of a siloxane epoxide compound, a cylcoaliphatic epoxide compound, or a glycidyl ether epoxide compound), one or more oxetane groups (e.g. , a four member cyclic ether), or a combination of such groups).
  • epoxide groups e.g., a three member cyclic ether
  • siloxane epoxide compound e.g., a siloxane epoxide compound, a cylcoaliphatic epoxide compound, or a glycidyl ether epoxide compound
  • oxetane groups e.g. , a four member cycl
  • Polymerization of the cationic reagent typically includes a ring-opening reaction of the cyclic ether group(s) of the reagent (e.g., cationic ring opening polymerization).
  • the polymerization can be initiated by, for example, an initiating species (e.g., a cation) formed by a photoinitiator upon absorption of light by the photoinitiator.
  • the cationic reagent can be a monomer or an oligomer (e. g., a compound having multiple repeat units, at least some of which (e.g., most or all) typically have at least one cyclic ether group).
  • the cationic reagent is an oxetane compound having at least one oxetane group (e. g., at least two oxetane groups or more).
  • the printing material may include a combination of such oxetane compounds.
  • examples of cationic reagents including at least one epoxide group include cycloaliphatic epoxy compounds such as bis-(3,4-epoxycyclohexyl)adipate, 3,4- epoxycyclohexyl methyl-3,4-epoxycyclohexane carboxylate, and 7-Oxa-bicyclo[4.1 .0]heptane-3-carboxylic acid 7- oxabicyclo[4.1 .0] hept-3 -ylmethyl ester; ether derivatives including diol derivatives such as 1 ,4-butanediol
  • glycidyl ethers such as n-butyl glycidyl ether, distilled butyl glycidyl ether, 2-ethyl hexyl glycidyl ether, C8-C10 aliphatic glycidyl ether, C12 C14 aliphatic glycidyl ether, O-cresyl glycidyl ether, P-tertiary butyl phenyl glycidyl ether, nonyl phenyl glycidyl ether, phenyl glycidyl ether,
  • the ink includes at least two (e.g.
  • the ink can include at least one oxetane compound in combination with one or more other cationic reagents (e.g., in combination with at least one other oxetane compound, at least one cationic reagent, x. Additional examples for an epoxide group containing
  • reagents are cycloaliphatic epoxies such as (3',4'- Epoxycyclohexane)methyl 3,4-epoxycyclohexylcarboxylate; 3,4-Epoxycyclohexylmethyl-3',4'- epoxycyclohexanecarboxylate modified epsilon- caprolactone; cyclohexanol, 4,4'-(1 -methylethylidene)bis-, polymer with (chloromethyl) oxirane; epoxidized
  • cycloaliphatic epoxies such as (3',4'- Epoxycyclohexane)methyl 3,4-epoxycyclohexylcarboxylate; 3,4-Epoxycyclohexylmethyl-3',4'- epoxycyclohexanecarboxylate modified epsilon- caprolactone; cyclohexanol, 4,4'-(1 -methyleth
  • composition of the present disclosure are low molecular weight mono- or multifunctional compounds, such as monomers carrying one, two, three or more functional groups that can react in a curing reaction.
  • a useful reactive diluent is for example a low molecular compound having at least one functional group reactive with the oligomer in the presence of a curing agent.
  • Typical examples are low molecular weight acrylate esters including mono-, di-, and tri- (meth)acrylates or mixtures thereof.
  • Reactive materials used in cationic curable formulations may be low molecular weight monomer and co-monomers that are used as diluents.
  • the oxetane compound includes at least one of 3-ethyl-3-hydroxymethyl- oxetane, 3,3'-oxybis(methylene)bis(3-ethyloxetane), 1 ,4-bis[(3-ethyl-3- oxetanylmethoxy)methyl]benzene and 3-ethyl-3-[(2- ethylhexyloxy)methyl]oxetane.
  • Diols and polyols are used as chain extenders and usually increase the flexibility of the system and the curing speed.
  • examples of those materials are 2-Oxepanone, polymer with 2-ethyl-2-(hydroxymethyl)-1 ,3-propanediol, 2- oxepanone, polymer with 2, 2-bis(hydroxymethyl)-1 ,3-propanediol.
  • the rheology modifier acts as thickening agent, it can be an organic or inorganic rheology modifier, both of which are well-known in the art.
  • the most common types of modified and unmodified inorganic rheology modifiers that are useful for the present disclosure, are attapulgite clays, bentonite clays, organoclays, and treated and untreated synthetic silicas, such as fumed silica.
  • Most inorganic thickeners and rheology modifiers are supplied as powders. If they are properly dispersed into a coating, they usually function as suspending or gelling agents and, thus, help to avoid sedimentation. Inorganic rheology modifiers tend to have high yield values and are characterized as thixotropes.
  • disclosure can be subdivided into products based on natural raw materials, like cellulose or xanthan, and products based on synthetic organic chemistry, like polyacrylates, polyurethanes or polyamides.
  • synthetic organic chemistry like polyacrylates, polyurethanes or polyamides.
  • Other rheology modifiers and thickeners such as polyamides, organoclays etc., can also be used.
  • the curing agent used for the present disclosure suitably is at least one photoinitiator. It can be another initiator that is known for this type of reactions, i.e. a compound that generates radicals under predetermined conditions.
  • a useful curing agent can be selected depending for example on the UV source or other reaction condition. It has been found that photoinitiators, such as a-hydroxyketone, a-aminoketone, phenylglyoxylate, benzyldimethyl- ketal, etc., are suitable. In one embodiment for a specific formulation phosphine oxide is used.
  • photoinitiators suitable for radical curing formulations of the present disclosure are 1 -hydroxy- cyclohexyl-phenylketone, available as Irgacure 184, 2-benzyl-2- dimethylamino-1 -(4-morpholinophenyl)-butanone-1 , available as Irgacure 369 from BASF Ludwigshafen, Germany, bis(2,4,6- trimethylbenzoyl)- phenylphosphinoxide, available as Irgacure 819, diphenyl- (2,4,6- trimethylbenzoyl)phosphinoxide, available as TPO.
  • a photoinitiating system includes at least one photoinitiator capable of absorbing light (e.g., ultraviolet light) to provide an initiating species capable of initiating polymerization of a cationic reagent or combination of such reagents.
  • a photoinitiator may generate a strong acid upon absorbing light.
  • the strong acid is an initiating species that initiates a ring opening reaction of a cyclic ether of a cationic reagent, which can then react (e.g., polymerize) with the cyclic ether of another cationic reagent.
  • Examples of photoinitiators include arylsulfonium salts (e.g. , PL 6992 and PL 6976) such as mixed triarylsulfonium hexafluoroantimonate salts triarylsulfonoumhexafluoroantimonate or
  • hexafluorophosphate, iodonium salts e.g., Deuteron UV 2275 available from Deuteron GmbH, Achim Germany; Rhodorsil 2076 available from Rhodia, Lyon, France; LV9385C available from General Electric, Waterford, N.Y.; Bis(t- butylphenyl)iodonium hexafluorophosphate) available from Hampford Research, Inc. of Stratford, Conn.; and Irgacure 250 available from Ciba Specialty
  • the photoinitiating system includes a sensitizer in combination with the photoinitiator.
  • the sensitizer absorbs light (e.g., ultraviolet light and/ or visible light) and transfers energy to the photoinitiator, which provides an initiating species (e.g., a strong acid) capable of initiating
  • the sensitizer can enhance the rate of photoinitiation.
  • the sensitizer can provide a photoinitiator with the ability to initiate polymerization of cationic reagents upon exposure to longer wavelength light than in the absence of the sensitizer.
  • Sensitizers can be useful in, for example, inks including particles (e. g., pigment particles such as rutile titania used to color the ink and/or provide opacity) which can decrease the penetration depth of ultraviolet light absorbed by the photo initiator.
  • Sensitizers typically absorb the longer wave length light more efficiently than the photoinitiator itself thereby enhancing curing of the ink.
  • the ink includes photoinitiator in the amount of at least about 0.5% by weight (e.g., at least about 1 %).
  • the total amount of photoinitiator of the ink may be about 3% or less by weight (e. g., about 2% or less).
  • the ink includes sensitizer in the amount of at least about 0.01 % by weight (e. g., at least about 0.05%).
  • the total amount of sensitizer of the ink may be about 0.5% or less by weight (e.g., about 0.1 % or less).
  • Exemplary sensitizers include at least one aromatic group and include compounds such as 9, 10-diethoxy anthracene, 2-ethyl-9, 10- dimethoxyanthracene, isopropylthioxanthone, or perylene.
  • Photoinitiators that are used for cationic curable materials are of type of the onium salts as sulfonium, iodonium or diazonium salts. The onium salt absorbs UV light and undergoes cleavage to form protonic acid.
  • Cationic photoinitiators suitable for the present disclosure are Iodonium (4-methylphenyl)[4-(2- methylpropyl)phenyl]-, hexafluorophosphate(l -) (1 : 1 ) (4-methylphenyl)[4-(2- methylpropyl) phenyl]-, hexafluorophosphate in propylene carbonate (Irgacure 250 from BASF), triarylsulfonium hexafluorophosphate with sensitizer (H-Nu C390 from Spectra), 4, 4'-dimethyl-diphenyl iodonium hexafluorophosphate & 3- ethyl- 3- hydroxymethloxetane (Omnicat 445 from IGM).
  • Antharacene or thioxantone sensitizers may be needed to enhance the reactivity of the photoinitiator and extend the curing range to a longer
  • the common sensitizers are 9, 10-Dibutoxyanthracene
  • the radical curable pseudoplastic material or gel 104 comprises:
  • Curable oligomer 30-70%
  • Curing agent 0.2-7%
  • Rheology modifier 1 -10%
  • the oligomer typically is one of the family of curable oligomers as
  • oligomers for example one having at least one ethylenically unsaturated bond such as acrylated and methacrylated oligomers and in particular acrylated epoxies, polyesters, polyethers and urethanes.
  • the oligomer typically is present be in a proportion of 30-70% by weight.
  • the reactive diluent can be a substance as described above and typically can be a mono, di and tri functional monomer and the proportion would be about 30-70% by weight.
  • the reactive diluents or monomers would typically be low molecular weight acrylate esters including methacrylates, monoacrylates, diacrylates and triacrylates.
  • the rheology modifier can be one or more of the substances described above and suitable for use in the current material composition is a filler that provides for a suitable viscosity of the material to be extruded and enhances the shear-thining properties, such as fumed silica or clay.
  • the curing agent can be a compound as described above, in particular a photo initiator, and a useful initiator is an alpha cleavage type unimolecular decomposition process photo initiator that absorbs light between 230 and 420 nm, to yield free radical(s).
  • alpha cleavage photo initiators could be 1 -hydroxycyclohexyl phenyl ketone (Irgacure 184 from BASF), 2- Benzyl-2-dimethylamino1 -(4-morpholinophenyl) (Irgacure 369 from BASF), Bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide (Irgacure 819 from BASF) or Diphenyl(2,4,6-trimethylbenzoyl) phosphineoxide (Irgacure TPO from BASF).
  • Irgacure 184 1 -hydroxycyclohexyl phenyl ketone
  • 2- Benzyl-2-dimethylamino1 -(4-morpholinophenyl) Irgacure 369 from BASF
  • Bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide Irgacure 819 from BA
  • the cationic curable pseudoplastic material or gel 104 comprises (all ingredients are given by weight percentage):
  • the hybrid material was formulated containing both radically and cationically cured materials.
  • BR 144 and BR 441 -B are polyether and polyester urethane acrylates available from a number of suppliers.
  • CN 981 is urethane acrylate .
  • Ebecryl 3300 is epoxy acrylate.
  • 03-849 is polyester acrylate.
  • TPO is phosphine oxide photo initiator.
  • SR 506D, SR 238, SR 833S, SR 351 are mono, di and tri functional reactive diluents.
  • Aerosil 200 is fumed silica such as Evonic-Aerosil 200. 091 ]
  • Tables 1 and 2 provide four tested suitable for radical curing formulations of the pseudoplastic material or gel. 104. All percentages refer to weight parts of component or compound per weight of the total composition.
  • Table 1 has the formulations 1 -4 without performance additives and Table 2 has formulations 5- 8 with the performance additives to demonstrate how different UV curable ingredients, including urethane, polyester and epoxy acrylates together with mono, di and tri functional monomers can be combined in the formulation.
  • Polyester 12 acrylate
  • the formulations were prepared by dissolving the curing agent, which could be a photoinitiator, in the reactive diluent and then adding the solution to the oligomer.
  • Performance additives such as surfactants, fillers, and pigments, could be added at the mixing stage and rheology modifiers could be added close to the end of the mixing stage. Different mixing orders have been tested, but no significant changes in the pseudoplastic material properties have been noted.
  • the mix was prepared by using a mixer and under reduced pressure or vacuum to accomplish simultaneous formulation degassing.
  • the prepared formulation of the pseudoplastic material had a viscosity of about 100000.00 mPa-s to 400,000 mPa-s at atmospheric pressure.
  • the viscosity was measured at room temperature (25°C) by using a Brookfield RVDV-E viscometer available from Brookfield AMETEK 1 1 Commerce Boulevard Middleboro, Massachusetts, U.S.A. 02346.
  • the pseudoplastic material formulation has shown different degrees of shear thinning properties under different degrees of agitation and pressure.
  • FIG. 5 is a graph that demonstrates the variations of viscosity at different shear rates.
  • Examples of cationic curable (Formulations #9 and #10) and hybrid curable (Formulations #1 1 and #12) pseudoplastic materials formulations are shown in Table 3. All numbers refer to weight parts of component or compound per weight of the total composition.
  • Cationic formulation will contain at least one epoxide reagent, at least one cationic photoinitiator, at least one sensitizer, at least one rheology modifier and optionally a performance improving additive/filler.
  • Hybrid formulation will typically contain at least one acrylate reagent, at least one cationic reagent, both cationic and radical photoinitiators, at least one rheology modifier and optionally a performance improving additive /filler.

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Abstract

La technique de fabrication d'objets en trois dimensions actuelle comprend le dépôt d'une matière pseudoplastique dans un état d'agrégat de gel. Le gel s'écoule à travers une buse de dépôt, car l'agitation et la pression appliquées cisaillent les liaisons et induisent une rupture de l'élasticité du matériau. L'élasticité se rétablit immédiatement après que le gel ait quitté la buse, et le gel se solidifie pour conserver sa forme et sa résistance.
PCT/IL2017/050953 2016-09-21 2017-08-28 Procédé et appareil pour la fabrication d'objets 3d Ceased WO2018055609A1 (fr)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020257231A1 (fr) * 2019-06-21 2020-12-24 President And Fellows Of Harvard College Accepteurs d'excitons triplets pour augmenter les seuils de conversion-élévation pour l'impression 3d
CN115943074A (zh) * 2019-05-13 2023-04-07 汉高股份有限及两合公司 用于3d印刷施用的双重固化环氧配制物
EP4118055A4 (fr) * 2020-03-13 2024-05-15 Mighty Buildings, Inc. Procédé de production d'une composition de matériau de construction pour l'impression 3d
US12291662B2 (en) 2018-11-27 2025-05-06 President And Fellows Of Harvard College Photon upconversion nanocapsules for 3D printing and other applications

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070241482A1 (en) * 2006-04-06 2007-10-18 Z Corporation Production of three-dimensional objects by use of electromagnetic radiation
US20080118666A1 (en) * 2001-11-27 2008-05-22 Thommes Glen A Radiation curable resin composition for making colored three dimensional objects
US20100197848A1 (en) * 2007-08-02 2010-08-05 Kandathil Eapen Verghese Amphiphilic block copolymers and inorganic nanofillers to enhance performance of thermosetting polymers
US20100304088A1 (en) * 2006-05-01 2010-12-02 Paulus Antonius Maria Steeman Radiation curable resin composition and rapid three dimensional imaging process using the same
US20110104500A1 (en) * 2009-03-13 2011-05-05 John Southwell Radiation curable resin composition and rapid three-dimensional imaging process using the same
US8598245B2 (en) * 2011-04-14 2013-12-03 Alliant Techsystems Inc. Insulating materials comprising polysilazane, methods of forming such insulating materials, and precursor formulations comprising polysilazane
US8785515B2 (en) * 2007-05-11 2014-07-22 Sun Chemical Corporation Sensitizer for cationic photoinitiators
US9216543B1 (en) * 2014-06-08 2015-12-22 Massivit 3D Printing Technologies Ltd Method of forming a three-dimensional object

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080118666A1 (en) * 2001-11-27 2008-05-22 Thommes Glen A Radiation curable resin composition for making colored three dimensional objects
US20070241482A1 (en) * 2006-04-06 2007-10-18 Z Corporation Production of three-dimensional objects by use of electromagnetic radiation
US20100304088A1 (en) * 2006-05-01 2010-12-02 Paulus Antonius Maria Steeman Radiation curable resin composition and rapid three dimensional imaging process using the same
US8785515B2 (en) * 2007-05-11 2014-07-22 Sun Chemical Corporation Sensitizer for cationic photoinitiators
US20100197848A1 (en) * 2007-08-02 2010-08-05 Kandathil Eapen Verghese Amphiphilic block copolymers and inorganic nanofillers to enhance performance of thermosetting polymers
US20110104500A1 (en) * 2009-03-13 2011-05-05 John Southwell Radiation curable resin composition and rapid three-dimensional imaging process using the same
US8598245B2 (en) * 2011-04-14 2013-12-03 Alliant Techsystems Inc. Insulating materials comprising polysilazane, methods of forming such insulating materials, and precursor formulations comprising polysilazane
US9216543B1 (en) * 2014-06-08 2015-12-22 Massivit 3D Printing Technologies Ltd Method of forming a three-dimensional object

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12291662B2 (en) 2018-11-27 2025-05-06 President And Fellows Of Harvard College Photon upconversion nanocapsules for 3D printing and other applications
CN115943074A (zh) * 2019-05-13 2023-04-07 汉高股份有限及两合公司 用于3d印刷施用的双重固化环氧配制物
WO2020257231A1 (fr) * 2019-06-21 2020-12-24 President And Fellows Of Harvard College Accepteurs d'excitons triplets pour augmenter les seuils de conversion-élévation pour l'impression 3d
EP4118055A4 (fr) * 2020-03-13 2024-05-15 Mighty Buildings, Inc. Procédé de production d'une composition de matériau de construction pour l'impression 3d

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