JP2020151971A - Three-dimensional molded product manufacturing apparatus, three-dimensional molded product manufacturing method, and three-dimensional molding program - Google Patents

Abstract

To provide a method for manufacturing a three-dimensional molded product that can obtain a three-dimensional molded product having excellent surface properties and realize high productivity.SOLUTION: A method for manufacturing a three-dimensional molded product includes a molding layer forming process in which a molding material is discharged during a main scanning operation to form a molding layer. In the process of forming one molding layer, when main scanning areas of a head overlap, a discharge amount of the molding material in a previous scan at an overlapping portion is smaller than a discharge amount of the molding material in the final scan.SELECTED DRAWING: Figure 14

Description

The present invention relates to a three-dimensional model manufacturing apparatus, a three-dimensional model manufacturing method, and a three-dimensional model program.

As a manufacturing device for a three-dimensional model that forms a three-dimensional model (three-dimensional model), the modeling material that forms the three-dimensional model is discharged into the modeling area and then cured to form a layered model, and the layered model is formed. There is known a material injection modeling method (material jet method) in which a three-dimensional model is formed by sequentially laminating. In the material injection modeling method, two types of materials are used: a model material and a support material for supporting the model material during modeling.

As such a material jet type three-dimensional modeling device, for example, a three-dimensional modeling device provided with a roller for scraping off excess of the modeling material by pressing while rotating has been proposed (see, for example, Patent Document 1). ).
Further, the inkjet head used is smaller than the modeling area, and a method is known in which the head or stage moves a plurality of times in the head nozzle direction (sub-scanning direction) after scanning to form a modeled object larger than the head nozzle length. There is.
However, in that case, when scanning the area overlapping with the pre-scan, there is a problem that the modeled object of the pre-scan collides with the roller. Therefore, it is necessary to scan a large amount in the sub-scanning direction, which causes a problem that the non-printing time becomes long and the modeling speed, that is, the productivity is lowered.
On the other hand, if the operation in the sub-scanning direction is reduced so as not to impair productivity, the roller collides with the modeled object, vibration of the roller and the device occurs, the surface of the modeled object becomes rough, and the roller rotation speed becomes unstable. There is a problem that it stops.

Therefore, for example, for the purpose of preventing collision between the roller and the modeled object, the width of the roller portion is the distance between the orifices located at both ends in the sub-scanning direction of the model material discharging nozzle provided in the modeling material discharging means, and It has been proposed that the support material discharge nozzle is formed to be narrower than the distance between the orifices located at both ends in the sub-scanning direction (see, for example, Patent Document 2).

An object of the present invention is to provide a method for producing a three-dimensional model that can obtain a three-dimensional model having excellent surface properties and realize high productivity.

The method for producing a three-dimensional modeled object of the present invention as a means for solving the above-mentioned problems includes a modeling layer forming step of discharging a modeling material during a main scanning operation to form a modeling layer, and forming one modeling layer. In the process, when the main scanning areas of the heads overlap, the discharge amount of the modeling material in the previous scanning in the overlapping portion is smaller than the discharging amount of the modeling material in the final scanning.

According to the present invention, it is possible to provide a three-dimensional model having excellent surface properties and to provide a method for producing a three-dimensional model that can realize high productivity.

(A) to (G) of FIG. 1 are schematic explanatory views showing an example of a method of manufacturing a three-dimensional model using the device for manufacturing a three-dimensional model of the present invention. FIG. 2 is a schematic view showing the modeling material and the flattening member of the return path in the later stage of FIG. 1 (E). FIG. 3 is an explanatory view showing a state in which the flattening member scrapes off the surface of the excess return molding material in the later stage of FIG. 1 (E). FIG. 4 is a schematic view showing a return molding material and a flattening member when the ratio of roller shaving white is 12% in the stage after FIG. 1 (E). FIG. 5 is a schematic view showing a return molding material and a flattening member when the ratio of roller shaving white is 30% in the stage after FIG. 1 (E). FIG. 6 is a schematic view showing a return molding material and a flattening member when the ratio of roller shaving white is 4% in the stage after FIG. 1 (E). FIG. 7 is a schematic view showing a return molding material and a flattening member when the ratio of roller shaving white is 0% in the stage after FIG. 1 (E). FIG. 8A is an enlarged photograph of an end portion of a three-dimensional model formed with a roller-shaving white ratio of 0%. FIG. 8B is an enlarged photograph of an end portion of a three-dimensional model formed with a roller-shaving white ratio of 12%. FIG. 8C is an enlarged photograph of an end portion of a three-dimensional model formed with a roller-shaving white ratio of 30%. FIG. 9 is a graph showing the relationship between the ratio of the roller shaving white and the radius of the virtual circle overlapping the end of the three-dimensional model. FIG. 10 is a schematic view showing a method of increasing the size of the droplets of the modeling material on the return route by making the pulse voltage of the droplets of the modeling material on the return route equal to or higher than the pulse voltage of the droplets of the modeling material on the outward route. FIG. 11 is a graph showing the relationship between the droplets of the modeling material (weight of the modeling material) with respect to the pulse voltage. FIG. 12 is a graph showing the relationship of the film thickness with respect to the pulse voltage. FIG. 13 is a graph showing the relationship of the film thickness with respect to the discharge amount on the return path. In FIG. 14, the number of pulses of the droplets of the modeling material on the return route before landing is set to be equal to or greater than the number of pulses of the droplets of the modeling material on the outward route before landing, and the droplets of the plurality of discharged modeling materials are united during flight. It is explanatory drawing which shows the method of enlarging the droplet of the modeling material of the return path. FIG. 15 is an example of a front explanatory view of a main part of a three-dimensional model manufacturing apparatus. FIG. 16 is an example of a plan explanatory view of a main part of a three-dimensional model manufacturing apparatus. FIG. 17 is an example of an explanatory side view of a main part of a three-dimensional model manufacturing apparatus. FIG. 18 is a diagram showing a state in which a modeling layer is formed by ejecting a modeling material by changing the nozzle position during reciprocation. FIG. 19 is a block explanatory view of a control unit of a three-dimensional model manufacturing apparatus. FIG. 20 is a diagram showing an example of a functional configuration of a three-dimensional model manufacturing apparatus. FIG. 21 is a flowchart showing a processing procedure of the three-dimensional modeling program in the control unit of the three-dimensional modeling object manufacturing apparatus. FIG. 22 is a schematic view of the sub-scanning direction and the main scanning direction in the modeling of the material jet method. FIG. 23 is a diagram illustrating the heights of the rollers and the modeled object at each scan.

(Manufacturing method of three-dimensional model, manufacturing device of three-dimensional model, and three-dimensional model program)
The method for manufacturing a three-dimensional model of the present invention includes a modeling layer forming step of ejecting a modeling material during a main scanning operation to form a modeling layer, and the main scanning regions of the heads overlap in one modeling layer forming step. In this case, the discharge amount of the modeling material in the previous scan at the overlapping portion is smaller than the discharge amount of the modeling material in the final scan, and further steps are included as necessary.

In the present invention, the term "main scanning region" means an region in which the inkjet head scans (moves) for layer formation in the main scanning operation. That is, the main scanning region is a region where the modeling material can be ejected from the inkjet head for forming the modeling layer during the main scanning, and when such regions overlap (that is, the inkjet head is used multiple times). If there is an area to be scanned), the layer will be formed after multiple scans. Of the plurality of scans, the last scan is referred to as "last scan", and the other scans are referred to as "preceding scan".

The three-dimensional model manufacturing apparatus of the present invention has a modeling layer forming means for forming a modeling layer by ejecting a modeling material during a main scanning operation, and in one modeling layer forming means, the main scanning region of the head is formed. In the case of overlapping, the discharge amount of the modeling material in the previous scan at the overlapping portion is smaller than the discharge amount of the modeling material in the last scan, and further means other means as necessary.

The three-dimensional modeling program of the present invention discharges a modeling material during the main scanning operation to form a modeling layer.
In the formation of one modeling layer, when the main scanning areas of the heads overlap, the process of reducing the discharge amount of the modeling material in the previous scan at the overlapping portion to the discharge amount of the modeling material in the final scan is performed by the computer. To execute.

It should be noted that the control performed by the control means or the like in the "three-dimensional model manufacturing apparatus" of the present invention is synonymous with the implementation of the "method for manufacturing the three-dimensional model" of the present invention. The details of the "method for manufacturing a three-dimensional model" of the present invention will also be clarified through the explanation of the "manufacturing apparatus for the above". Further, since the "three-dimensional modeling program" of the present invention is realized as the "three-dimensional modeling object manufacturing apparatus" of the present invention by using a computer or the like as a hardware resource, the "three-dimensional modeling object manufacturing" of the present invention is manufactured. The details of the "three-dimensional modeling program" of the present invention will also be clarified through the explanation of the "device".

The present invention includes a modeling layer forming step of ejecting a modeling material during the main scanning operation to form a modeling layer, and when the main scanning regions of the head overlap in one modeling layer forming step, the overlapping portion is used. The discharge amount of the modeling material in the previous scan is smaller than the discharge amount of the modeling material in the last scan, the height of the modeled object can be lowered, and the collision between the roller and the modeled object can be reduced. .. In addition, the amount of movement of the head can be minimized, and productivity can be increased.
As a method of making the discharge amount of the outbound modeling material in the overlapping portion smaller than the ejection amount of the outbound modeling material, for example, the pulse voltage of the droplets of the outbound modeling material is the droplet of the inbound modeling material. Examples thereof include a method of adjusting the discharge amount of the outbound modeling material so as to be smaller than the pulse voltage by reducing the droplets of the outbound modeling material.
In the overlapping portion, it is preferable not to discharge the modeling material in the outbound scanning. As a result, the height of the modeled object can be further lowered, so that the amount of movement of the head can be minimized and the productivity can be increased while suppressing the collision between the roller and the modeled object.

In one aspect of the present invention, the head is relatively moved in the sub-scanning direction within the same modeling layer.

In one aspect of the present invention, scanning of the outward path and the return path in the same modeling layer is bidirectional printing, and in the bidirectional printing, the head is moved in the sub-scanning direction.

In one aspect of the present invention, after ejecting the modeling material in the outward scanning, the head is moved in the sub-scanning direction during acceleration / deceleration in the main scanning direction.

In one aspect of the invention, the movement of the head in the sub-scanning direction is rendering.
Rendering means moving in the sub-scanning direction after reciprocating scanning on the same layer.

Here, the method for producing a three-dimensional model of the present invention is shown in FIGS. 1 (A) to 1 (G), and includes an outward path modeling layer forming step and a returning path modeling layer forming step.
In the outbound modeling layer forming step, when a highly viscous liquid modeling material is ejected from a discharge means such as a nozzle in the outward path (see FIG. 1 (A)), the ejected modeling material bends in the center due to surface tension. It has a rounded end (see FIG. 1 (B)). After that, the discharged outbound modeling material is cured by a curing means such as a UV irradiation unit to form an outbound modeling layer (see FIG. 1C).
In the return path modeling layer forming step, in the return path, a liquid modeling material having a high viscosity so as to overlap the cured outbound modeling layer is discharged from a discharge means such as a nozzle in a larger amount than the outward path (FIG. 1 (D). ) And (E)), the flattening member is brought into contact with the surface of the discharged return molding material to flatten the return molding material (see FIG. 1 (F)). Then, the flattened return molding material is cured by a curing means such as a UV irradiation unit to form a return shaping layer (see FIG. 1 (G)).
The method for producing a three-dimensional model of the present invention is performed on the surface of the return model material at a later stage of FIG. 1 (E), before the return model material is cured, as shown in FIGS. 2 and 3. A flattening member such as a roller is brought into contact with the material, and excess material for forming the return path is scraped off. As a result, the surface of the return molding material can be flattened (see FIG. 1 (F)), and the end portion of the return molding material can be sharpened as shown by X in FIG. 1 (F). ..
Further, as shown in FIG. 1 (G), after the surface of the return path modeling material is flattened, it is cured to form the return path modeling layer. Therefore, the method for manufacturing a three-dimensional model of the present invention can form a layered model having a flat surface without bending in the central portion, and by repeating the lamination of the layered model, the end portion is formed. It is possible to produce a high-definition three-dimensional model with sharpness and excellent flatness.

In the present invention, it is preferable that the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route, whereby the roller cutting white can be secured thickly and the sharpness of the end portion is improved. Will be described with reference to FIGS. 8A to 8C.
8A-8C show roller-shaving whites with respect to the minimum thickness of the layered model after discharging the return model material onto the outward model layer (that is, the height of the center portion of the return model material). (That is, the distance between the roller and the hardened outbound modeling layer) is 0%, 12%, and 30%, respectively, and an enlarged photograph of the end of the shaped three-dimensional model is shown.
When the total discharge amount of the modeling material on the return route is the same as the total discharge amount of the modeling material on the outward route and the ratio of the roller sharpening white is 0%, the end of the three-dimensional model to be manufactured is shown in FIG. 8A (enlarged). As shown in (Magnification: 100 times), it is rounded and has insufficient sharpness.
On the other hand, when the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route and the ratio of the roller sharpening white is 12%, the end of the three-dimensional model to be manufactured is shown in FIG. 8B. As shown in (magnification: 100 times), the sharpness of the end portion of the manufactured three-dimensional model is better than that in the case where the ratio of the roller shaving white is 0% (FIG. 8A).
Further, when the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route and the ratio of the roller sharpening white is 30%, the end portion of the three-dimensional model to be manufactured is shown in FIG. 8C (enlarged). As shown in (Magnification: 100 times), the sharpness of the end portion of the manufactured three-dimensional model is further improved as compared with the case where the ratio of the roller shaving white is 12% (FIG. 8B).
8A to 8C are magnified to each magnification using a microscope (device name: VHX-500, manufactured by KEYENCE CORPORATION).

Further, in FIGS. 8A to 8C, a virtual circle was superposed on the end portion of the three-dimensional modeled object, and the radius (mm) of the virtual circle overlapping the end portion was obtained. Similarly, the radius (mm) of the virtual circle was determined when the ratio of the roller shaving white was 10.0% or more and 45.0%. FIG. 9 shows the radius (mm) of the virtual circle that overlaps the end of the three-dimensional model with respect to the ratio of the roller-shaving white when the distance in the Z direction is constant (22.5 μm).
In FIG. 9, the smaller the radius (mm) of the virtual circle, the higher the sharpness, and the larger the radius (mm) of the virtual circle, the more rounded the end. Further, in FIG. 9, X, Y, and Z represent the directions of the three-dimensional model.
As can be seen from FIG. 9, as the proportion of roller-cutting white increases, the radius (mm) of the virtual circle that overlaps the end of the three-dimensional model tends to decrease. Therefore, the sharpness of the end portion of the three-dimensional model to be manufactured can be improved as the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route and the ratio of the roller shaving white is increased. Recognize.

<Experiment>
Using the first modeling material (model material) and the second modeling material (support material) having the following composition, using a three-dimensional printer, based on the modeling conditions shown in Table 1, XZ in a cube of 20 mm x 20 mm x 20 mm. No. where the surface contacts the model material and the support material. 1-No. The three-dimensional model of 5 was modeled.

-First modeling material-
Isobonyl acrylate (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 60% by mass, tricyclodecanemethanol diacrylate (manufactured by Daicel Ornerk) 23% by mass, UB-6600 (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 10% by mass, IRUGACURE TPO 3% by mass (manufactured by BASF) and 4% by mass of IRUGACURE 184 (manufactured by BASF) were stirred in a beaker for 30 minutes to prepare a first molding material.

-Second modeling material-
Acryloylmorpholin (manufactured by KJ Chemicals Co., Ltd.) 40.0 g, 1,5-pentanediol (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 10.0 g, polypropylene glycol 1 (trade name: Actol D-1000, Mitsui Chemicals SKC Polyurethane Co., Ltd.) , Number average molecular weight: 1,000) 50.0 g and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (trade name: Irgacure 819, manufactured by BASF) 2.0 g are added and stirred. Mixing was used to prepare a second molding material.

Next, with respect to the obtained three-dimensional model, the surface roughness Rz of the surface of the model portion and the occurrence of cracks after removing the support portion of the three-dimensional model were evaluated as follows. The results are shown in Table A.

-Surface roughness Rz-
The surface roughness Rz was evaluated using VK-X150 (manufactured by KEYENCE CORPORATION) in the range of 1 mm × 1 mm at the interface between the model material and the support material.

-Cracking-
The presence or absence of cracks was visually observed.

From the results in Table A, No. As shown in 2, when the first modeling material (model material) and the second modeling material (support material) are simultaneously reciprocally discharged and cured, No. 1 and No. It was found that cracks were generated and the surface roughness Rz was larger than that of 3.
On the other hand, No. As shown in 4 and 5, when the first modeling material is discharged and cured, and then the second modeling material is discharged and cured, no crack is generated, the surface roughness Rz is small, and the support is provided. It was found that a smooth model part surface was obtained after the part was removed.

<Outward modeling layer forming means and outward modeling layer forming process>
The outbound modeling layer forming means is a means for discharging the modeling material in the outward path to form the modeling layer in the outward path. The outbound modeling layer may be formed by curing the discharged modeling material to form the outward modeling layer.
The outbound modeling layer forming step is a step of discharging the modeling material in the outward path to form the modeling layer in the outward path. In the outbound modeling layer forming step, the discharged modeling material may be cured to form the outward modeling layer.
It is preferable that the modeling material is discharged by using the modeling material discharge member.
The curing of the modeling material is preferably performed using the modeling material curing member.

<< Modeling material discharge member >>
The modeling material discharge member is a member that discharges the modeling material on the outward route.
The modeling material discharge member is not particularly limited as long as it discharges the modeling material on the outward route, and can be appropriately selected depending on the intended purpose. For example, a known material such as a head can be used.
The head is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a piezoelectric element (piezo element) type head and a thermal expansion (thermal) type head. Among these, a piezoelectric element (piezo element) type head is preferable.

<< Outbound modeling material >>
The outbound modeling material for forming the outbound modeling layer is not particularly limited, and can be appropriately selected based on the performance required for constructing the main body for modeling the three-dimensional modeled object.
Examples of the modeling material include a model material and a support material.

The outbound modeling material is not particularly limited as long as it is a liquid that cures by applying energy such as light or heat, and can be appropriately selected depending on the purpose. However, polymerization of monofunctional monomers, polyfunctional monomers, etc. It preferably contains a sex monomer and an oligomer, and further contains other components as needed. Preferably, it has liquid physical properties such as viscosity and surface tension that can be discharged by a modeling material discharge head used for a modeling material jet printer or the like.

-Polymerizable monomer-
Examples of the polymerizable monomer include a monofunctional monomer and a polyfunctional monomer. These may be used alone or in combination of two or more.

--Monofunctional monomer ---
Examples of the monofunctional monomer include acrylamide, N-substituted acrylamide derivative, N, N-di-substituted acrylamide derivative, N-substituted methacrylamide derivative, N, N-di-substituted methacrylamide derivative, acrylic acid and the like. These may be used alone or in combination of two or more. Among these, acrylamide, N, N-dimethylacrylamide, N-isopropylacrylamide, acryloylmorpholine, hydroxyethylacrylamide, and isobornyl (meth) acrylate are preferable.

As the monofunctional monomer, an organic polymer can be obtained by polymerizing.

The content of the monofunctional monomer is preferably 0.5% by mass or more and 90% by mass or less with respect to the total amount of the modeling material.

The monofunctional monomer other than the above is not particularly limited and may be appropriately selected depending on the intended purpose. For example, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth). ) Acrylate, caprolactone-modified tetrahydrofurfuryl (meth) acrylate, 3-methoxybutyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, lauryl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, isodecyl (meth) acrylate , Isooctyl (meth) acrylate, tridecyl (meth) acrylate, caprolactone (meth) acrylate, ethoxylated nonylphenol (meth) acrylate and the like.

--Polyfunctional monomer ---
The polyfunctional monomer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include bifunctional monomers and trifunctional or higher functional monomers. These may be used alone or in combination of two or more.

Examples of the bifunctional monomer include tripropylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, and neopentyl glycol hydroxypivalic acid ester di. (Meta) acrylate, neopentyl glycol ester di (meth) acrylate of hydroxypivalate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di ( Meta) acrylate, 1,9-nonanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, caprolactone-modified hydroxypivalate neopentyl glycol ester Examples thereof include di (meth) acrylate, propoxylated opentyl glycol di (meth) acrylate, ethoxy-modified bisphenol A di (meth) acrylate, polyethylene glycol 200 di (meth) acrylate, and polyethylene glycol 400 di (meth) acrylate. These may be used alone or in combination of two or more.

Examples of the trifunctional or higher monomer include trimethylolpropantri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, triallyl isocyanurate, and ε-caprolactone-modified dipentaerythritol tri (meth). Meta) acrylate, ε-caprolactone-modified dipentaerythritol tetra (meth) acrylate, (meth) acrylate, ε-caprolactone-modified dipentaerythritol penta (meth) acrylate, ε-caprolactone-modified dipentaerythritol hexa (meth) acrylate, tris (meth) 2-Hydroxyethyl) isocyanurate tri (meth) acrylate, ethoxylated trimethylol propantri (meth) acrylate, propoxylated trimethylol propantri (meth) acrylate, propoxylated glyceryl tri (meth) acrylate, pentaerythritol tetra (meth) Examples thereof include acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol hydroxypenta (meth) acrylate, ethoxylated pentaerythritol tetra (meth) acrylate, and penta (meth) acrylate ester. These may be used alone or in combination of two or more.

− Oligomer −
As the oligomer, a low polymer of the above-mentioned monomer or one having a reactive unsaturated bond group at the terminal may be used alone or in combination of two or more.

-Other ingredients-
The other components are not particularly limited and may be appropriately selected depending on the intended purpose. For example, a surfactant, a polymerization inhibitor, a polymerization initiator, a colorant, a viscosity modifier, an adhesive imparting agent, and an antioxidant. Examples include agents, anti-aging agents, cross-linking accelerators, UV absorbers, plasticizers, preservatives, dispersants and the like.

--Surfactant ---
Examples of the surfactant include a molecular weight of 200 or more and 5,000 or less, specifically, a PEG-type nonionic surfactant [an addition of 1 to 40 mol of ethylene oxide of nonylphenol (hereinafter abbreviated as “EO”). Stearic acid EO 1-40 molar adducts, etc.], polyhydric alcohol-type nonionic surfactants (sorbitan palmitate monoester, sorbitan stearic acid monoester, sorbitan stearic acid triester, etc.), fluorine-containing surfactants (perfluoroalkyl) EO1 to 50 molar adducts, perfluoroalkyl carboxylates, perfluoroalkyl betaines, etc.), modified silicone oils [polyether-modified silicone oils, (meth) acrylate-modified silicone oils, etc.] and the like. These may be used alone or in combination of two or more.
The content of the surfactant is preferably 3% by mass or less, and more preferably 0.1% by mass or more and 5% by mass or less from the viewpoint of the content effect and the physical properties of the photocured product, based on the total amount of the modeling material.

--Polymerization inhibitor ---
Examples of the polymerization inhibitor include phenol compounds [hydroquinone, hydroquinone monomethyl ether, 2,6-di-t-butyl-p-cresol, 2,2-methylene-bis- (4-methyl-6-t-butylphenol)). , 1,1,3-Tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane, etc.], sulfur compounds [dilaurylthiodipropionate, etc.], phosphorus compounds [triphenylphosphite, etc.] , Amine compounds [phenothiazine, etc.] and the like. These may be used alone or in combination of two or more.
The content of the polymerization inhibitor is preferably 5% by mass or less based on the total amount of the modeling material, and more preferably 0.1% by mass or more and 5% by mass or less from the viewpoint of monomer stability and polymerization rate.

--Polymerization initiator ---
Examples of the polymerization initiator include thermal polymerization initiators and photopolymerization initiators. Among these, a photopolymerization initiator is preferable from the viewpoint of storage stability.
As the photopolymerization initiator, any substance that generates radicals by irradiation with light (particularly ultraviolet rays having a wavelength of 220 nm to 400 nm) can be used.
Examples of the photopolymerization initiator include acetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, benzophenone, 2-chlorobenzophenone, p, p'-dichlorobenzophenone, p, p-bisdiethylaminobenzophenone, and Michler ketone. Benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-propyl ether, benzoin isobutyl ether, benzoin-n-butyl ether, benzylmethyl ketal, thioxanthone, 2-chlorothioxanthone, 2-hydroxy-2- Methyl-1-phenyl-1-one, 1- (4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, methylbenzoylformate, 1-hydroxycyclohexylphenylketone, azobisisobutyronitrile, Examples thereof include benzoyl peroxide and di-tert-butyl peroxide. These may be used alone or in combination of two or more.

The thermal polymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose. For example, an azo-based initiator, a peroxide initiator, a persulfate initiator, a redox (oxidation-reduction) initiator, etc. Can be mentioned.

Examples of the azo-based initiator include VA-044, VA-46B, V-50, VA-057, VA-061, VA-067, VA-086, 2,2'-azobis (4-methoxy-2, 4-Dimethylvaleronitrile) (VAZO 33), 2,2'-azobis (2-amidinopropane) dihydrochloride (VAZO 50), 2,2'-azobis (2,4-dimethylvaleronitrile) (VAZO 52) , 2,2'-azobis (isobutyronitrile) (VAZO 64), 2,2'-azobis-2-methylbutyronitrile (VAZO 67), 1,1-azobis (1-cyclohexanecarbonitrile) (VAZO) 88) (above, manufactured by DuPont Chemical), 2,2'-azobis (2-cyclopropylpropionitrile), 2,2'-azobis (methylisobutyrate) (V-601) (above, Wako Pure Chemical Industries, Ltd.) (Made by Co., Ltd.), etc.

Examples of the peroxide initiator include benzoyl peroxide, acetyl peroxide, lauroyl peroxide, decanoyl peroxide, disetylperoxydicarbonate, and di (4-t-butylcyclohexyl) peroxydicarbonate (trade name:). Perkadox 16S, manufactured by Akzo Nobel), di (2-ethylhexyl) peroxydicarbonate, t-butylperoxypivalate (trade name: Lupersol 11, manufactured by Elf Atochem), t-butylperoxy-2-ethylhexa Examples thereof include Noate (trade name: Trigonox 21-C50, manufactured by Akzo Nobel), dicumyl peroxide and the like.

Examples of the persulfate initiator include potassium persulfate, sodium persulfate, ammonium persulfate and the like.

Redox initiators include, for example, a combination of a persulfate initiator and a reducing agent such as sodium metahydrosulfate and sodium hydrogen sulfite, or a system based on an organic peroxide and a tertiary amine (eg,). , A system based on benzoyl peroxide and dimethylaniline), a system based on an organic hydroperoxide and a transition metal (for example, a system based on cumene hydroperoxide and cobalt naphthate), and the like.

The content of the polymerization initiator is preferably 10% by mass or less, more preferably 5% by mass or less, based on the total amount of the modeling material.

-Colorant-
As the colorant, dyes and pigments that are soluble or stably dispersed in the molding material and have excellent thermal stability are suitable. Among these, a soluble dye (Solvent Dye) is preferable. Further, it is possible to mix two or more kinds of colorants in a timely manner by adjusting the color or the like.

<< Modeling material hardening member >>
The modeling material curing member is a member that cures the discharged outbound modeling material to form an outbound modeling layer.
The modeling material curing member is not particularly limited as long as it cures the discharged outbound modeling material to form the outbound modeling layer, and can be appropriately selected according to the purpose. For example, an ultraviolet irradiation device. And so on.

-Ultraviolet irradiation device-
Examples of the ultraviolet (UV) irradiation device include a high-pressure mercury lamp, an ultra-high pressure mercury lamp, and a metal halide lamp.
The high-pressure mercury lamp is a point light source, but the DeepUV type, which has high light utilization efficiency in combination with an optical system, can irradiate in a short wavelength region.
Metal halide is effective for colored substances because it has a wide wavelength range, and halides of metals such as Pb, Sn, and Fe are used and can be selected according to the absorption spectrum of the polymerization initiator. The lamp used for curing is not particularly limited and may be appropriately selected depending on the purpose. For example, a commercially available lamp such as an H lamp, a D lamp, or a V lamp manufactured by FusionSystem is also used. can do.

The device for manufacturing a three-dimensional object is preferably heaterless, and preferably capable of modeling at room temperature.

<Return path shaping layer forming means and return path forming layer forming process>
The return path modeling layer forming means is a means for forming a modeling layer by discharging a modeling material. In the return path modeling layer forming means, after the flattening member is brought into contact with the surface of the discharged return path modeling material to flatten the return path modeling material, the return path modeling material is cured to form the return path modeling layer. It may be formed.
The return path modeling layer forming step is a step of discharging the modeling material to form the modeling layer. In the return path modeling layer forming step, the flattening member is brought into contact with the surface of the discharged return path modeling material to flatten the return path modeling material, and then the return path modeling material is cured to form the return path modeling layer. It may be formed.
It is preferable that the modeling material is discharged by using the modeling material discharge member.
The curing of the modeling material is preferably performed using the modeling material curing member.

<< Modeling material discharge member >>
The modeling material discharge member is a member that discharges the modeling material on the return path.
The modeling material discharge member is not particularly limited as long as it discharges the modeling material on the return route, and can be appropriately selected according to the purpose. For example, the same material as the modeling material discharge member on the outward route is used. Can be done.
As the modeling material discharge member on the return route, the same one as the modeling material discharge member on the outward route may be used, or a different material may be used.
As the modeling material discharge member on the return route, for example, the same modeling material discharge member as the modeling material discharge member on the outward route can be used by making the modeling material discharge member on the outward route movable in both directions. Further, for example, by fixing the position of the modeling material discharge member and making the stage on which the three-dimensional model is placed movable in both directions, the modeling material discharge member on the return route and the modeling material discharge member on the outward route can be separated. Can be the same.

The return molding material is preferably discharged so as to overlap the hardened outward molding layer on the return trip, but the return molding material may include a region that does not overlap the outward molding layer on the return trip. There may be a deviation in the overlap between the modeling material and the modeling layer on the outbound route.
For example, in FIG. 1 (C), after forming the cured outbound modeling layer, in FIG. 1 (D), the position of the outbound modeling material is shifted by about 80 μm in the Y direction (secondary scanning direction), and then the return path is performed. For example, stacking modeling materials.

The total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route.
The total discharge amount of the modeling material on the return route is preferably 1.2 times or more and 3 times or less the total discharge amount of the modeling material on the outward route.
As a method of adjusting the total discharge amount of the modeling material on the return route to be larger than the total discharge amount of the modeling material on the outward route, for example, the droplet of the modeling material on the return route is larger than the droplet of the modeling material on the outward route. There is a way to do it.
As a method of making the droplets of the return molding material larger than the droplets of the outward shaping material, for example, the pulse voltage of the droplets of the return shaping material is set to be equal to or higher than the pulse voltage of the droplets of the outward shaping material. A method of enlarging the droplets of the return molding material, making the number of pulses of the return molding material droplets before landing equal to or greater than the number of pulses of the outward shaping material droplets before landing, and discharging multiple modeling materials Examples include a method of enlarging the droplets of the modeling material on the return route by coalescing the droplets during flight.

A method of increasing the pulse voltage of the droplets of the modeling material on the return route to be equal to or higher than the pulse voltage of the droplets of the modeling material on the outward route to enlarge the droplets of the modeling material on the return route will be described with reference to FIG.
Here, an example of a liquid discharge head using a piezoelectric element as a pressure generating means will be described.

By applying the outward drive pulse P1 to the piezoelectric element of the head 11 (see FIG. 10A), the droplet D1 of the outward modeling material is ejected from the nozzle (see FIG. 10B). After that, by applying the drive pulse P2 of the return path to the piezoelectric element of the head 11 (see FIG. 10A), the droplet D2 of the modeling material of the return path is ejected from the nozzle (see FIG. 10B).
Further, as shown in FIG. 10A, the drive pulse P1 on the outward path is derived from the waveform element a that descends from the intermediate potential Ve to a predetermined falling potential, the waveform element b that holds the falling potential, and the falling potential. It is composed of a waveform element c that rises to an intermediate potential Ve. By giving the waveform elements a to c, the droplets are ejected from the nozzle.
The drive pulse P2 on the return path is the same as the drive pulse P1 on the outward path.

Here, as shown in FIG. 11, the higher the pulse voltage, the larger the volume (unit: pL) of the droplets of the modeling material tends to be.
Further, FIG. 12 shows the relationship with the pulse voltage when the vertical axis is the film thickness in FIG. 11, and the higher the pulse voltage, the higher the film thickness tends to be. The waveform corresponds to the return path.
Further, FIG. 13 shows the relationship between the discharge amount on the return path and the film thickness, and the film thickness is proportional to the discharge amount on the return path. From the results of FIG. 13, the target discharge amount on the outward route is 25 pL, and the film thickness is about 14 μm.
Therefore, as shown in FIG. 10A, the falling potential of the drive pulse P2 on the return path is set to be equal to or higher than the falling potential of the drive pulse P1 on the outward path, that is, the pulse voltage of the droplet of the modeling material on the return path is set to that of the outward path. By setting the voltage to be equal to or higher than the pulse voltage of the droplets of the modeling material, the droplet D2 due to the drive pulse P2 on the return path can form a droplet having a larger volume than the droplet D1 due to the drive pulse P1 on the outward path (FIG. 10). See (b)).

Make the number of pulses of the droplets of the modeling material on the return route before landing equal to or greater than the number of pulses of the droplets of the modeling material on the outward route before landing, and combine the droplets of the multiple modeling materials discharged during flight to model the return route. A method of enlarging the droplets of the material will be described with reference to FIG.
Here, an example of a liquid discharge head using a piezoelectric element as a pressure generating means will be described.

FIG. 14 is an explanatory diagram provided for explanation when the modeling material for the outward route is formed by one drop and the modeling material for the return route is formed by a droplet obtained by combining two drops.
By applying the outward drive pulse P1 to the piezoelectric element of the head 11 (see FIG. 14A), the droplet D1 of the outward modeling material is ejected from the nozzle (see FIG. 14B). After that, by applying the return drive pulse P2 to the piezoelectric element of the head 11 (see FIG. 14A), two droplets D2 and D3 of the return path modeling material are sequentially ejected from the nozzle (FIG. 14 (Fig. 14). b) See).

Here, as shown in FIG. 14A, the falling potential of the drive pulse P3 on the return path is made larger than the falling potential of the drive pulse P2 on the return path, that is, the pulse of the droplet D3 of the modeling material on the return path. By making the voltage larger than the pulse voltage of the droplet D2 of the modeling material of the return path, when the start-up time constant is the same, the velocity Vj3 of the droplet D3 by the drive pulse P3 of the return path is the droplet by the drive pulse P2 of the return path. It is faster than the speed Vj2 of D2 (see FIG. 14B).
Therefore, the droplet D3 catches up with the droplet D2 and coalesces during flight, and can form one droplet having a larger volume than the droplet D1 of the outward modeling material as the return modeling material D2 + D3 (). See FIG. 14 (b)).

In the present invention, the nozzle that discharges the modeling material on the outward route and the nozzle that discharges the modeling material on the return route are the same (using one common nozzle), which makes the landing position of the outward route and the return route accurate. Is preferable.
It is important to accurately control the landing position of ink droplets from the viewpoint of performing high-definition modeling and modeling with accurate dimensions. However, even if the position accuracy of the XY coordinates is accurately controlled, the nozzle position varies within the range of the geometrical tolerance, and this variation cannot be canceled even if the position accuracy of the XY coordinates is accurate. However, if the same nozzle is used, the nozzle position is the same, so that the geometrical tolerance is virtually eliminated, so that the configuration is preferable in order to make the landing position accurate.

Here, the order in which the first modeling material (for example, a model material) and the second modeling material (for example, a support material) when laminating three-dimensional objects are discharged and cured will be described.
In the present invention, since the discharge amount is different between the outward route and the return route, the first modeling material and the second modeling material are alternately discharged, that is, when the first modeling material is discharged on the outward route and the second modeling material is discharged on the return route. The heights of the two cured products do not match, and the desired three-dimensional model cannot be obtained. Therefore, the first modeling material is discharged on the first outward route, the first modeling material is discharged on the first return route, the second modeling material is discharged on the second outward route, and the second modeling material is discharged on the second return route. By discharging the modeling material, a modeling layer having the same height can be formed.

As a method of curing the second modeling material after curing the first modeling material, the modeling layer for curing each modeling material can also be separated.
That is, after the first modeling material is reciprocated m times in the nth layer, discharged and cured, the first modeling material in the n + m layer is discharged and cured, and at the same time, the second molding material is second in the nth layer. By discharging the modeling material and curing it, it is possible to obtain a three-dimensional model having a smooth surface of the model portion after removing the support portion. However, n means a natural number and m means a positive or negative integer. m is preferably 2. When m = 1, the surface roughness Rz is high, and when m ≧ 3, there is no change in the surface roughness Rz, which is not preferable because of a decrease in productivity.

<< Modeling material for the return trip >>
The shape material for the return route is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the same material as the shape material for the return route can be used.

The viscosity of the molding material on the return path is not particularly limited and may be appropriately selected depending on the intended purpose. However, the shape of the discharged material is flattened by the flattening member after being discharged until it is cured. Is preferably 100 mPa · s or less at 25 ° C., more preferably 3 mPa · s or more and 20 mPa · s or less, and particularly preferably 6 mPa · s or more and 12 mPa · s or less at 25 ° C.
The viscosity can be measured in an environment of 25 ° C. using, for example, a rotational viscometer (VISCOMATE VM-150III, manufactured by Toki Sangyo Co., Ltd.).

The surface tension of the modeling material on the return route is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of flattening the surface of the modeling material, it is preferably 20 mN / m or more and 45 mN / m or less, and 25 mN. More preferably, it is / m or more and 34 mN / m or less.
The surface tension can be measured using, for example, a surface tension meter (automatic contact angle meter DM-701, manufactured by Kyowa Interface Science Co., Ltd.).

<< Flattening member >>
The flattening member is a member that flattens the return molding material by abutting the surface of the discharged return molding material.
The flattening member is not particularly limited as long as it flattens the return molding material by abutting it on the surface of the discharged return molding material, and can be appropriately selected according to the purpose. For example, rollers, blades and the like can be mentioned.

In the three-dimensional model manufacturing apparatus, the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route. Therefore, the thickness of the modeling material on the return route is formed to be thicker than the thickness of the modeling layer on the outward route.
As shown in FIG. 2, in the three-dimensional model manufacturing apparatus, a rotating roller is laterally abutted as a flattening member on the end of the return modeling material that is thicker than the thickness of the outward modeling layer. This makes it possible to scrape off excess return shaping material, including rounded edges, flatten the surface of the return shaping material, and sharpen the edges of the return shaping material.

The angle (θ in FIG. 2) formed by the wall surface at the end of the modeling material on the return path and the support supporting the three-dimensional model is preferably 80 degrees or more and 100 degrees or less, and an angle close to 90 degrees (vertical) is preferable. More preferred. When the angle is 80 degrees or more and 100 degrees or less, when the flattening member comes into contact with the return molding material from the lateral direction, the excess end of the return molding material is scraped off to remove the surface of the return molding material. Can be flattened.

In the three-dimensional model manufacturing apparatus of the present invention, the thickness of the modeling material on the return path is formed to be thicker than the thickness of the modeling layer on the outward path, so that the roller shaving white (distance between the roller and the cured modeling layer on the outward path) is formed. Many can be secured.
The ratio of roller cutting white to the minimum thickness of the layered model after discharging the return model material onto the outward model layer (that is, the height of the center portion of the return model material) is 10%. The above is preferable. When the ratio of the roller shaving white to the minimum thickness of the layered model is 10% or more, it is possible to prevent the roller from colliding with the hardened outward model layer, and further, the surface of the return model material may be wavy. , It is possible to prevent the roller from being damaged.
The thickness of the roller shaving white is preferably 3 μm or more, and more preferably 5 μm or more.

As shown in FIG. 3, the scraped return molding material is conveyed on the roller as the roller rotates, and is recovered by the recovery member.
The recovery member is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include blades.

The shape of the roller as the flattening member is not particularly limited as long as it can scrape off the forming material for the return path, and can be appropriately selected according to the purpose. For example, a circular shape or a perfect circle can be used. Can be mentioned.
The flattening member may have vibration and a touch width, and as shown in FIGS. 4 to 7, a deviation in the direction of gravity may occur.
The deviation of the flattening member in the direction of gravity between the outward path and the return path is preferably 10 μm or less, and more preferably 5 μm or less.

<< Modeling material hardening member >>
The molding material hardening member is a member that hardens the flattened return molding material to form a return molding layer.
The molding material curing member is not particularly limited as long as it cures the flattened return molding material to form the return molding layer, and can be appropriately selected according to the purpose. For example, in the outward trip. A material similar to the molding material hardening member can be used.
As the molding material hardening member on the return trip, the same one as the molding material hardening member on the outward trip may be used, or a different one may be used.

As for the method for manufacturing the three-dimensional model, the three-dimensional model can be manufactured by repeating the outbound modeling layer forming step and the returning modeling layer forming step a plurality of times.

As the flattening member, it is preferable that each layered object is in contact with each other. As a result, the edges can be sharpened and the flatness can be improved for each layered model.
The layered model is preferably formed in two passes, an outward route and a return route.
By repeating the lamination of the layered model, it is possible to manufacture a high-definition three-dimensional model having sharp edges and excellent flatness.

Hereinafter, an outline of an example of an apparatus for manufacturing a three-dimensional model of the present invention will be described. 15 is a front explanatory view of a main part of the device, FIG. 16 is a plan view of the device, and FIG. 17 is a side view of the device.

The three-dimensional model manufacturing device (hereinafter, also referred to as “three-dimensional modeling device”) 10 is a material injection modeling device, and a three-dimensional model is modeled by laminating the modeling layer 30 which is a layered model. It includes a stage 14 which is a modeling stage, and a modeling unit 20 which forms a modeling layer 30 while sequentially laminating the modeling layer 30 on the stage 14.

The modeling unit 20 includes a first head 11 which is a discharge means for discharging a modeling material to a unit holder 21, a UV irradiation unit 13 for irradiating ultraviolet rays as active energy rays, and a flattening means for flattening the modeling layer 30. The flattening roller 16 is provided. In addition to the modeling material as a model material for modeling the three-dimensional modeled object, the second head 12 for discharging the support material supporting the modeling of the three-dimensional modeled object can be provided.

Here, in the X direction, two second heads 12 are arranged with the first head 11 interposed therebetween, UV irradiation units 13 are arranged outside the two second heads 12, and further, outside of the UV irradiation unit 13. A flattening roller 16 is arranged as a flattening member in each of the above.

The modeling material is supplied to the first head 11 via a supply tube or the like by a cartridge 60 that is replaceably mounted on the cartridge mounting portion 56. When a modeling material having a color such as black, cyan, magenta, or yellow is used, a plurality of nozzle rows for ejecting droplets of each color can be arranged on the first head 11.

The UV irradiation unit 13 cures the modeling material discharged from the first head 11. When the UV irradiation unit 13 includes a support material, the UV irradiation unit 13 cures the modeling layer 30 made of the support material discharged from the second head 12.
When an ultraviolet irradiation lamp is used, it is preferable to provide a mechanism for removing ozone generated by ultraviolet irradiation.
Examples of the type of ultraviolet irradiation lamp include a high-pressure mercury lamp, an ultra-high pressure mercury lamp, and a metal halide lamp. The ultra-high pressure mercury lamp is a point light source, but the ultraviolet irradiation lamp with high light utilization efficiency in combination with the optical system can irradiate in the short wavelength region. Since metal halide has a wide wavelength range, it is effective in curing colored substances. Halides of metals such as Pb, Sn, and Fe are used and can be selected according to the absorption spectrum of the photopolymerization initiator.

The flattening roller 16 flattens the surface of the molding layer 30 cured on the stage 14 by relative movement with the stage 14 while being rotated.
The term "on the stage 14" means that the stage 14 and the modeling layer 30 to be laminated on the stage 14 are included unless otherwise specified.

The unit holder 21 of the modeling unit 20 is movably held by the guide members 54 and 55 arranged in the X direction.
Further, a maintenance mechanism 61 for maintaining and recovering the first head 11 is arranged on one side of the modeling unit 20 in the X direction.

Further, the guide members 54 and 55 holding the unit holder 21 of the modeling unit 20 are held by the side plates 70 and 70 on both sides. The side plates 70 and 70 have a slider portion 72 movably held by a guide member 71 arranged on the base member 7, and the modeling unit 20 can reciprocate in the Y direction orthogonal to the X direction.
The stage 14 is moved up and down in the Z direction by the raising and lowering means 15. The elevating means 15 is movably arranged on the guide members 75 and 76 arranged in the X direction on the base member 7.

Next, an outline of the modeling operation by the three-dimensional modeling device 10 will be described with reference to FIG.
First, the modeling unit 20 is moved in the Y direction to be positioned on the stage 14. Next, while moving the stage 14 with respect to the stopped modeling unit 20, the model material 301 is discharged from the first head 11 to the modeling region (region constituting the three-dimensional model). When a support material is used, the support material 302 is discharged from the second head 12 to a support area (area to be removed after modeling) other than the modeling area.

Next, the UV irradiation unit 13 irradiates the model material 301 and the support material 302 with ultraviolet rays to cure them, and forms a modeling layer 30 for one layer including the modeling object 17 made of the modeling material and the modeling object 18 made of the support material. To do.

The modeling layer 30 is repeatedly modeled and sequentially laminated to form a target three-dimensional model composed of the model material 301 while supporting the model material 301 with the support material 302. For example, in the example of FIG. 15, five layers of the modeling layers 30A to 30E are laminated.

Here, every time a plurality of modeling layers 30 are laminated (it does not have to be a fixed value), for example, every 10 layers are laminated, the flattening roller 16 is pressed against the outermost modeling layer 30 to be flattened. As a result, the thickness accuracy and flatness of the modeling layer 30 are ensured.
When a roller-shaped member such as the flattening roller 16 is used as the flattening means, the flattening effect is improved by rotating the flattening roller 16 in the direction opposite to the moving direction in the X direction. Can be made to.

Further, in order to keep the gap between the modeling unit 20 and the outermost modeling layer 30 constant, here, the stage 14 is lowered by the elevating means 15 every time one layer of the modeling layer 30 is formed. The modeling unit 20 may be raised and lowered.

The three-dimensional modeling apparatus may include a collection member for the model material 301 and the support material 302, a recycling mechanism, and the like. Further, a discharge state detecting means for detecting the non-discharge nozzles of the first head 11 and the second head 12 may be provided. Further, the ambient temperature in the apparatus at the time of modeling may be controlled.

FIG. 18 is a diagram showing a state in which a modeling layer is formed by ejecting a modeling material by changing the nozzle position during reciprocation.
On the return trip, the Y coordinate is moved by 1 mm so that the head is interlaced from the position of the outward trip. Then, on the return route, discharge is performed using a nozzle that overlaps with the outward route.
It may be discharged to the same coordinates without moving in the Y direction at all on the return route. Then, the head moves to the next block and discharges.
Further, at the start position of the next layer, ejection is started from a position where the Y coordinate is shifted by 1 mm with respect to the current layer. After performing the movement of shifting 1 mm for each layer four times, the Y coordinate returns to the same Y coordinate five layers before. That is, the start position is repeated every 5 layers.
The reason for moving 1 mm on the outward and return paths and 1 mm for each layer is to improve the margin for nozzle removal.

(Three-dimensional modeling program)
In the three-dimensional modeling program of the present invention, the modeling material is discharged in the outward path to form the modeling layer in the outward path, the modeling material is discharged in the return path, the modeling layer in the return path is formed, and the outward path and the above are described in the same modeling layer. The computer is made to execute a process of reducing the discharge amount of the modeling material on the outward path to the discharge amount of the modeling material on the return path in the overlapping portion where the scanning of the return path overlaps.

As a process for reducing the discharge amount of the outbound modeling material in the overlapping portion or preventing the outbound modeling material from being ejected, for example, the pulse voltage of the droplets of the outbound modeling material is the return modeling material. Examples thereof include a method of adjusting the discharge amount of the outbound modeling material by making the droplets of the outbound modeling material smaller than the pulse voltage of the droplets.

The processing by the three-dimensional modeling program of the present invention can be executed by using a computer having a control unit constituting the three-dimensional modeling object manufacturing apparatus.

The outline of the control unit will be described with reference to FIG. FIG. 19 is a block explanatory view of the control unit.

The control unit 500 includes a CPU 501 that controls the entire device, a three-dimensional modeling program that includes a program for causing the CPU 501 to control a three-dimensional modeling operation including the control according to the present invention, and a ROM 502 that stores other fixed data. A main control unit 500A including a RAM 503 for temporarily storing modeling data and the like is provided.
Further, the control unit 500 includes a non-volatile memory (NVRAM) 504 for holding data even while the power supply of the device is cut off. Further, the control unit 500 includes an ASIC 505 that processes an input / output signal for controlling the entire device and image processing that performs various signal processing on the image data.
Further, the control unit 500 includes an I / F 506 for transmitting and receiving data and signals used when receiving modeling data from the external modeling data creating device 600.
The modeling data creation device 600 is an device that creates modeling data (cross-section data) that is slice data obtained by slicing a modeled object (three-dimensional modeled object) in the final form for each modeling layer, and is an information processing device such as a personal computer. It is composed of.

The control unit 500 includes an I / O 507 for capturing detection signals of various sensors.
Further, the control unit 500 includes a head drive control unit 508 that drives and controls the first head 11 of the modeling unit 20, and a head drive control unit 509 that drives and controls the second head 12.
Further, the control unit 500 has a motor drive unit 510 that drives a motor constituting the unit X direction moving mechanism 550 that moves the modeling unit 20 in the X direction, and a Y that moves the modeling unit 20 in the Y direction (sub-scanning direction). A motor drive unit 511 that drives a motor constituting the directional scanning mechanism 552 is provided.

The control unit 500 constitutes a motor drive unit 513 that drives a motor constituting the stage X-direction scanning mechanism 553 that moves the stage 14 in the X direction together with the elevating means 15, and an elevating means 15 that moves the stage 14 up and down in the Z direction. A motor drive unit 514 that drives the motor is provided. As described above, the modeling unit 20 may be moved up and down in the Z direction.

The control unit 500 includes a motor drive unit 516 that drives the motor 26 that rotationally drives the flattening roller 16, and a maintenance drive unit 518 that drives the maintenance mechanism 61 of the first head 11 and the second head 12.

The control unit 500 includes a curing control unit 519 that controls ultraviolet irradiation by the UV irradiation unit 13.
A detection signal such as a temperature / humidity sensor 560 that detects temperature and humidity as an environmental condition of the device and a detection signal of other sensors are input to the I / O 507 of the control unit 500.
An operation panel 522 for inputting and displaying information necessary for this device is connected to the control unit 500.
As described above, the control unit 500 receives the modeling data from the modeling data creating device 600. The modeling data is data (data in the modeling area) that forms the model 17 in each model layer 30 as slice data obtained by slicing the shape of the target three-dimensional model.

The main control unit 500A creates data in which the data of the support area for adding the support material is added to the modeling data (modeling area data), and gives the data to the head drive control units 508 and 509. The head drive control units 508 and 509, respectively, discharge the droplets of the model material 301 from the first head 11 into the modeling region, and discharge the droplets of the liquid support material 302 from the second head 12 into the support region.
The modeling device is configured by the modeling data creation device 600 and the three-dimensional modeling device 10.

FIG. 20 is a diagram showing an example of the functional configuration of the three-dimensional model manufacturing apparatus 100.
As shown in FIG. 20, the three-dimensional model manufacturing apparatus 100 includes an input unit 110, an output unit 120, a control unit 130, and a storage unit 140.
The control unit 130 has a modeling material discharge amount adjusting unit 131 for the outward route and a modeling material discharge amount adjusting unit 132 for the return route. The control unit 130 controls the entire three-dimensional model manufacturing apparatus 100.
The storage unit 140 has a modeling material discharge amount database 141 for the outward route and a modeling material discharge amount database 142 for the return route. Hereinafter, the "database" may be referred to as a "DB".

The outbound modeling material discharge amount adjusting unit 131 adjusts so that the outbound modeling material discharge amount is reduced or the outbound modeling material is not discharged. For example, as a process of reducing the discharge amount of the modeling material in the outward path in the overlapping portion to be smaller than the discharge amount of the modeling material in the return path, for example, the pulse voltage of the droplets of the modeling material in the outward path is the modeling of the return path. Examples thereof include a method of adjusting the discharge amount of the outbound modeling material by making the droplets of the outbound modeling material smaller than the pulse voltage of the material droplets.

The modeling material discharge amount adjusting unit 132 on the return route adjusts the discharge amount of the modeling material on the return route so as to increase. For example, (1) a method of adjusting the total discharge amount of the return molding material by enlarging the droplets of the return molding material, and (2) the droplets of a plurality of molding materials discharged on the return trip. Examples include a method of combining during flight and adjusting so that the total discharge amount of the modeling material on the return route is increased.
The adjusted information on the discharge amount of the modeling material on the return route is stored in the modeling material discharge amount DB 142 on the return route.

Next, the processing procedure of the three-dimensional modeling program of the present invention is shown. FIG. 21 is a flowchart showing a processing procedure of the three-dimensional modeling program in the control unit 130 of the three-dimensional modeling object manufacturing apparatus 100.

In step S110, when the control unit 130 of the three-dimensional model manufacturing apparatus 100 acquires the information data of the discharge amount A of the outward modeling material in the overlapping portion stored in the outward modeling material discharge amount DB 141 of the storage unit 140, The process shifts to S111.
In step S111, when the control unit 130 of the three-dimensional model manufacturing apparatus 100 acquires the information data of the discharge amount B of the return modeling material in the overlapping portion stored in the return modeling material discharge amount DB 142 of the storage unit 140, The process shifts to S112.
In step S112, when the discharge amount A of the modeling material on the outward route is equal to or greater than the discharge amount B of the modeling material on the return route, the process shifts to S113. On the other hand, when the discharge amount A of the modeling material on the outward route is smaller than the discharge amount B of the modeling material on the return route, this process ends.
In step S113, a process of reducing the discharge amount of the modeling material on the outward route is performed, and when the changed discharge amount of the modeling material on the outward route is stored in the modeling material discharge amount DB 141 of the outward route, the process is returned to the start.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

Here, FIG. 22 is a schematic view showing a sub-scanning direction and a main scanning direction in the modeling of the material jet method.
FIG. 23 is a diagram illustrating the heights of the rollers and the modeled object at each scan. When rendering in the sub-scanning direction occurs in the third scan in the sub-scanning direction and overlapping parts occur in the second and third scans, in the conventional technique, the height is the same as that of the three modeled objects in the third scan. As the rollers move, they come into contact with the modeled object and cause a collision.
On the other hand, in the present invention, by not modeling in the second scan at the overlapping portion or reducing the discharge amount of the modeling material in the second scan, there is no third model at the same position as the first roller, and in the third scan. No collision will occur.

(Example 1)
<Modeling material>
Model materials are isobornyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) 60 parts by mass, tripropylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.) 10 parts by mass, dipropylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.) 5 parts by mass, UB 20 parts by mass of -6600 (manufactured by Tokyo Chemical Industry Co., Ltd.) and 5 parts by mass of IRGCURE-TPO (manufactured by IGM) were mixed, stirred with a magnetic stirrer for 12 hours, and filtered with 13JP050AN (manufactured by Advantech). used.
Support materials are acryloylmorpholin (manufactured by KJ Chemicals Co., Ltd.) 40 parts by mass, polypropylene glycol molecular weight 700 (manufactured by Nichiyu Co., Ltd.) 40 parts by mass, 1,6-hexanediol (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 8 parts by mass, octanol. 8 parts by mass (manufactured by Tokyo Kasei Kogyo Co., Ltd.) and 4 parts by mass of IRGCURE-819 (manufactured by IGM) were mixed and filtered in the same manner as the model material.

<Modeling method>
Modeling was performed using an inkjet head MH2420 (manufactured by Ricoh Co., Ltd.). The model material was ejected from all nozzles 192 channels from the origins X0 and Y0 at the start position of the 1st scan and cured. In the 2nd scan, the model material was ejected and cured by 182 channels from the position moved by 192 channels in the sub-scanning direction (Y). Here, for 182 channels, the number of nozzles m to be overlapped when moving in the sub-scanning direction corresponds to 10. In the 3rd scan, model materials for all 192 channels were ejected from a position moved by 182 channels in the sub-scanning direction and cured. The total movement amount per layer corresponds to 566 channels of 192 × 3-10.
From the above, the three-dimensional model of Example 1 was obtained.

(Example 2)
In Example 1, the same as in Example 1 except that the discharge amount of the 1st scan was changed to 182 channels, the movement amount before the 2nd scan was changed to 182 channels, the discharge amount was changed to 192 channels, and the 3rd scan movement amount was changed to 192 channels. , A three-dimensional model of Example 2 was obtained. The total travel distance corresponds to 566 channels.

(Comparative Example 1)
In Example 1, a three-dimensional model of Comparative Example 1 was obtained in the same manner as in Example 1 except that the discharge amount of the 2nd scan was changed to 192 channels and the discharge amount of the 3rd scan was changed to 182 channels. The total travel distance corresponds to 566 channels.

(Comparative Example 2)
In Example 1, a three-dimensional model of Comparative Example 2 was obtained in the same manner as in Example 1 except that the discharge amount of the 2nd scan was changed to 192 channels and the movement amount of the 3rd scan was changed to 192 channels. The total travel distance corresponds to 576 channels.

(Comparative Example 3)
In Example 1, the three-dimensional model of Comparative Example 3 was formed in the same manner as in Example 1 except that the start position of the 1st scan was changed to (X0, Y-10) and the movement amount of the 3rd scan was changed to 192 channels. Obtained. The total travel distance corresponds to 576 channels.

Next, various characteristics of Examples 1 and 2 and Comparative Examples 1 and 3 were evaluated as follows. The results are shown in Table 1.

<Total distance traveled>
The total movement distance is the sum of the movement amounts in the sub-scan direction between 1 to 3 scans. It should be noted that there is a relationship that productivity decreases as the total travel distance increases.

<Collision>
The collision was evaluated based on whether a three-dimensional model having X = 5 mm, Y = 60 mm, and Z = 60 mm could be modeled. If the collision between the roller and the modeled object is large, the modeled object may fall inside the modeling area or be ejected outside the modeling area during the modeling process, so that the desired modeled object cannot be obtained.
[Evaluation criteria]
◯: Z = 60 mm can be modeled ×: Three-dimensional modeled object falls or falls when Z = 60 mm

In Table 1, the origin represents the point at which modeling starts at the four corners of the modeling area, n represents the total number of nozzles of the print head, and m represents the number of overlapping nozzles during scanning.

Examples of aspects of the present invention are as follows.
<1> Including a modeling layer forming step of discharging a modeling material during the main scanning operation to form a modeling layer.
In the process of forming one modeling layer, when the main scanning regions of the heads overlap, the discharge amount of the modeling material in the previous scan at the overlapping portion is smaller than the discharge amount of the modeling material in the final scan. This is a method for manufacturing a three-dimensional model.
<2> The method for manufacturing a three-dimensional model according to <1>, wherein the modeling material is not discharged in the previous scanning in the overlapping portion.
<3> The method for manufacturing a three-dimensional model according to any one of <1> to <2>, wherein the head is relatively moved in the sub-scanning direction within the same modeling layer.
<4> The step described in <3>, wherein the modeling layer forming step is bidirectional printing in which the modeling material is discharged in both the outward path and the return path in the main scanning direction, and the head is moved in the sub scanning direction in the bidirectional printing. This is a method for manufacturing a three-dimensional model.
<5> The method for manufacturing a three-dimensional model according to any one of <3> to <4>, wherein the head is moved in the sub-scanning direction during acceleration / deceleration in the main scanning direction after the modeling material is discharged on the outward path. is there.
<6> The method for manufacturing a three-dimensional model according to any one of <3> to <5>, wherein the movement of the head in the sub-scanning direction is rendering.
<7> The method for producing a three-dimensional model according to any one of <1> to <6>, which includes a flattening step of flattening the surface of the modeling layer formed on the return path.
<8> The method for manufacturing a three-dimensional model according to any one of <1> to <7>, wherein the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route.
<9> In any of the above <1> to <8>, the first modeling material is discharged and cured in the same modeling layer, and then the second modeling material is discharged and cured to obtain a model. This is the method for manufacturing a three-dimensional model as described.
<10> The first modeling material is discharged and cured in the nth modeling layer, and the second modeling material is discharged and cured in the n + mth modeling layer to obtain a modeled object. <9> (However, n means a natural number and m means a positive or negative integer) according to the above.
<11> The first modeling material is discharged to the nth modeling layer and cured, and the second modeling material is discharged to the n + 2nd modeling layer and cured to obtain a modeled object. <9> The method for producing a three-dimensional model according to the above (where n means a natural number).
<12> It has a modeling layer forming means for forming a modeling layer by discharging a modeling material during the main scanning operation.
In one molding layer forming means, when the main scanning areas of the heads overlap, the discharge amount of the modeling material in the previous scanning at the overlapping portion is smaller than the discharging amount of the modeling material in the final scanning. It is a manufacturing device for a three-dimensional model.
<13> The apparatus for manufacturing a three-dimensional model according to <12>, wherein the modeling material is not discharged in the previous scanning in the overlapping portion.
<14> The apparatus for manufacturing a three-dimensional model according to any one of <12> to <13>, wherein the head moves relatively in the sub-scanning direction within the same modeling layer.
<15> The bidirectional printing in which the modeling layer forming means ejects the modeling material in both the outward path and the return path in the main scanning direction, and the head is moved in the sub-scanning direction in the bidirectional printing. It is a manufacturing device for three-dimensional objects.
<16> The device for manufacturing a three-dimensional model according to any one of <13> to <15>, wherein the head is moved in the sub-scanning direction during acceleration / deceleration in the main scanning direction after discharging the modeling material on the outward path. is there.
<17> The apparatus for manufacturing a three-dimensional model according to any one of <13> to <15>, wherein the movement of the head in the sub-scanning direction is rendering.
<18> The apparatus for manufacturing a three-dimensional model according to any one of <13> to <17>, which includes a flattening step of flattening the surface of the modeling layer formed on the return path.
<19> The apparatus for manufacturing a three-dimensional model according to any one of <12> to <18>, wherein the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route.
<20> In any of the above <12> to <19>, after the first modeling material is discharged and cured in the same modeling layer, the second modeling material is discharged and cured to obtain a model. It is the manufacturing apparatus of the three-dimensional model described.
<21> During the main scanning operation, the modeling material is discharged to form a modeling layer.
In the formation of one modeling layer, when the main scanning areas of the heads overlap, the process of reducing the discharge amount of the modeling material in the previous scan at the overlapping portion to the discharge amount of the modeling material in the final scan is performed by the computer. It is a three-dimensional modeling program characterized by being executed by a computer.

The method for manufacturing a three-dimensional model according to any one of <1> to <11>, the apparatus for manufacturing a three-dimensional model according to any one of <12> to <20>, and the above-mentioned <21>. According to the three-dimensional modeling program, various problems in the past can be solved and the object of the present invention can be achieved.

Japanese Unexamined Patent Publication No. 2013-67118 Japanese Patent No. 5759850

Claims (13)

Including a modeling layer forming step of ejecting a modeling material during the main scanning operation to form a modeling layer.
In the process of forming one modeling layer, when the main scanning regions of the heads overlap, the discharge amount of the modeling material in the previous scan at the overlapping portion is smaller than the discharge amount of the modeling material in the final scan. A method for manufacturing a three-dimensional model. The method for manufacturing a three-dimensional model according to claim 1, wherein the modeling material is not discharged in the above scanning in the overlapping portion. The method for manufacturing a three-dimensional model according to any one of claims 1 to 2, wherein the head is relatively moved in the sub-scanning direction within the same modeling layer. The three-dimensional model according to claim 3, wherein the modeling layer forming step is bidirectional printing in which the modeling material is discharged in both the outward path and the return path in the main scanning direction, and the head is moved in the sub scanning direction in the bidirectional printing. Manufacturing method. The method for manufacturing a three-dimensional model according to any one of claims 3 to 4, wherein the head is moved in the sub-scanning direction during acceleration / deceleration in the main scanning direction after the modeling material is discharged on the outward path. The method for manufacturing a three-dimensional model according to any one of claims 3 to 5, wherein the movement of the head in the sub-scanning direction is rendering. The method for producing a three-dimensional model according to any one of claims 1 to 6, further comprising a flattening step of flattening the surface of the modeling layer formed on the return path. The method for manufacturing a three-dimensional model according to any one of claims 1 to 7, wherein the total discharge amount of the modeling material on the return route is larger than the total discharge amount of the modeling material on the outward route. The three-dimensional model according to any one of claims 1 to 8, wherein the first modeling material is discharged and cured in the same modeling layer, and then the second modeling material is discharged and cured to obtain a model. Production method. The solid according to claim 9, wherein the first modeling material is discharged and cured in the nth modeling layer, and the second modeling material is discharged and cured in the n + mth modeling layer to obtain a modeled object. Method of manufacturing a modeled object (where n means a natural number and m means a positive or negative integer). The solid according to claim 9, wherein the first modeling material is discharged to the nth modeling layer and cured, and the second modeling material is discharged to the n + 2nd modeling layer and cured to obtain a modeled object. A method for manufacturing a modeled object (where n means a natural number). It has a modeling layer forming means for forming a modeling layer by discharging a modeling material during the main scanning operation.
In one molding layer forming means, when the main scanning areas of the heads overlap, the discharge amount of the modeling material in the previous scanning at the overlapping portion is smaller than the discharging amount of the modeling material in the final scanning. Equipment for manufacturing three-dimensional objects. During the main scanning operation, the modeling material is discharged to form a modeling layer,
In the formation of one modeling layer, when the main scanning areas of the heads overlap, the process of reducing the discharge amount of the modeling material in the previous scan at the overlapping portion to the discharge amount of the modeling material in the final scan is performed by the computer. A three-dimensional modeling program characterized by being executed by a computer.