JP2016172420A - Three-dimensional molding apparatus, manufacturing method, and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide technology capable of suppressing decrease in apparent resolution in the technology of molding a colored three-dimensional object by discharging a liquid.SOLUTION: A three-dimensional molding apparatus 100 is provided, including a head part 50 that molds an object by discharging a liquid as a material of the object to each unit grid determined in accordance with the molding resolution in an X direction and the molding resolution in a Y direction of a cross-sectional body of the object and with a stacking pitch in a Z direction. The head part 50 includes a plurality of nozzle groups for discharging a liquid and can discharge an achromatic liquid and a plurality of types of chromatic liquids to express a designated color, each in a designated amount, to one unit grid while scanning in a predetermined direction. In the main scanning direction of the head part 50, a nozzle group for discharging the achromatic liquid is disposed on either side of a plurality of nozzle groups for discharging the plurality of types of chromatic liquids.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a three-dimensional modeling apparatus.

  In recent years, three-dimensional modeling apparatuses that employ inkjet technology have attracted attention. In a three-dimensional modeling apparatus that employs ink jet technology, the number of layers in the height direction (Z direction) is the number of steps for forming a cross-section for one layer along the horizontal direction (XY direction) by discharging a curable liquid. By doing so, modeling of a three-dimensional object is performed. For example, in the three-dimensional modeling apparatus described in Patent Document 1, color shading is expressed by superimposing a layer whose outer peripheral portion is colored and a layer whose outer peripheral portion is not colored.

JP 2011-73163 A JP 2001-150556 A JP 2005-67138 A JP 2010-58519 A

  However, the technique described in Patent Document 1 has a problem in that color reproducibility deteriorates because only one color can be expressed per layer when observed from the outside. Therefore, there is a need for a technique for improving color reproducibility in a technique for modeling a colored three-dimensional object by discharging a liquid.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms.

(1) According to one aspect of the present invention, there is provided a three-dimensional modeling apparatus that models a three-dimensional object by stacking a plurality of cross-sectional bodies in the Z direction. This three-dimensional modeling apparatus, for each unit lattice determined according to the modeling resolution in the X direction of the cross-sectional body, the modeling resolution in the Y direction of the cross-sectional body, and the stacking interval in the Z direction of the cross-sectional body, The head unit includes a head unit configured to form the object by discharging a liquid that is a material of the object, and the head unit includes a plurality of nozzle groups that discharge the liquid, and one unit cell while scanning in a predetermined direction. In contrast, the achromatic liquid and a plurality of types of chromatic liquids for representing the specified color can be ejected in specified amounts, respectively, and the plurality of types can be discharged in the main scanning direction of the head unit. The nozzle groups for discharging the achromatic liquid are respectively disposed on both sides of a plurality of nozzle groups for discharging the chromatic liquid.
In the case of the three-dimensional modeling apparatus having such a configuration, the chromatic liquid that is easily ejected into the unit cell during the reciprocating movement of the head unit in the main scanning direction, regardless of whether it is the forward path or the return path An achromatic liquid can be discharged on the upper part of the liquid crystal. When the achromatic color liquid is ejected onto the chromatic color liquid, the chromatic color liquid is spread by the achromatic color liquid, so that the saturation of the chromatic color observed from the surface of the object can be improved. In addition, with such a three-dimensional modeling apparatus, the amount of the chromatic liquid discharged to the unit cell can be adjusted in units smaller than the unit cell, so that a colored three-dimensional object is modeled. In this case, it is possible to suppress a decrease in the apparent resolution of the three-dimensional object.

(2) The three-dimensional modeling apparatus according to the above aspect further includes a control unit that controls the head unit, and the control unit controls the head unit to discharge the chromatic liquid onto the unit cell. The achromatic liquid may be ejected onto the upper portion of the ejected chromatic liquid in the Z direction.
With such a three-dimensional modeling apparatus, since the discharged chromatic liquid is spread by the achromatic liquid, the saturation of the chromatic color observed from the surface of the object can be improved.

(3) In the three-dimensional modeling apparatus of the above aspect, the control unit controls the head unit to discharge the achromatic liquid to the unit cell before discharging the chromatic liquid to the unit cell, The chromatic liquid may be discharged on the upper part of the discharged achromatic liquid in the Z direction.
With such a three-dimensional modeling apparatus, since the chromatic liquid is further spread by the achromatic liquid, the saturation of the chromatic color observed from the surface of the object can be further improved.

(4) In the three-dimensional modeling apparatus of the above aspect, the unit cell includes a plurality of sub unit cells, and the head unit includes the plurality of types of nozzle groups that discharge the achromatic liquid. The number of nozzle groups for discharging the chromatic liquid is set to be equal to or greater than the number of nozzle groups for discharging the chromatic liquid, and each of the nozzle groups for discharging the achromatic liquid is different from one of the plurality of types of chromatic liquids. The control unit controls the head unit, and when the discharge amount of the specific chromatic liquid to be discharged to one unit cell does not satisfy the spatial volume of the sub unit cell. Discharging the achromatic color liquid from the nozzle group of the achromatic color liquid associated with the specific chromatic color liquid, and filling the subunit cell with the specific chromatic color liquid and the achromatic color liquid. Also good.
In the three-dimensional modeling apparatus having such a form, when the spatial volume of the subunit cell is not filled with the chromatic liquid to be ejected, the achromatic liquid is ejected to fill the remaining space of the subunit cell. Therefore, the volume of the sub unit cell is made uniform and the volume of the unit cell is also made uniform. Therefore, a three-dimensional object can be accurately modeled.

(5) In the three-dimensional modeling apparatus according to the above aspect, the head unit includes a nozzle group that discharges white liquid, the achromatic liquid is a colorless liquid, and the control unit controls the head unit. Then, of the two unit cells adjacent to each other in the direction from the surface of the object to the inside, the chromatic liquid and the colorless liquid are discharged into a first unit cell located on the surface side of the object, The white liquid may be discharged into a second unit cell located on the inner side of the object.
With such a three-dimensional modeling apparatus, a white portion is formed inside the portion colored by the chromatic liquid in the object, so that the color density of the chromatic liquid can be expressed more accurately. Can do.

(6) According to another aspect of the present invention, there is provided a three-dimensional modeling apparatus that models a three-dimensional object by stacking a plurality of cross-sectional bodies in the Z direction. This three-dimensional modeling apparatus, for each unit lattice determined according to the modeling resolution in the X direction of the cross-sectional body, the modeling resolution in the Y direction of the cross-sectional body, and the stacking interval in the Z direction of the cross-sectional body, A head unit that shapes the object by discharging a liquid that is a material of the object; and a control unit that controls the head unit, wherein the head unit is an achromatic liquid for one unit cell. And a plurality of types of chromatic liquids for representing the specified color can be discharged in specified amounts, respectively, and the control unit controls the head unit to control the chromatic liquid in the unit cell. Before discharging the chromatic liquid, the achromatic color liquid is discharged to the unit cell, the chromatic color liquid is discharged to the upper part of the discharged achromatic color liquid in the Z direction, and the discharged chromatic color liquid is discharged. The achromatic liquid is discharged on the top in the Z direction. It is characterized in.
If it is a three-dimensional modeling apparatus of such a form, achromatic liquid will be discharged by the upper part and the lower part of the chromatic liquid discharged in a unit cell. Thus, the chromatic liquid is spread by these achromatic liquids, and the saturation of the chromatic color observed from the surface of the object can be improved.

  The present invention can be realized in various forms other than the form as a three-dimensional modeling apparatus. For example, a manufacturing method in which a three-dimensional modeling apparatus manufactures a three-dimensional object, a computer program for a computer to model a three-dimensional object by controlling the three-dimensional modeling apparatus, or a non-primary recording of the computer program It can be realized in the form of a tangible recording medium or the like.

It is explanatory drawing which shows schematic structure of the three-dimensional modeling apparatus as 1st Embodiment. It is explanatory drawing which shows schematic structure of a head part. It is a flowchart of a three-dimensional modeling process. It is a figure for demonstrating the method of modeling a three-dimensional object. It is a figure for demonstrating the lamination order of the ink discharged from the head part. It is the figure which illustrated the 1st unit cell after ink discharge. It is a figure for demonstrating an example of the effect of 1st Embodiment. It is the figure which illustrated the 1st unit lattice after ink discharge in a modification. It is explanatory drawing which shows schematic structure of the head part of 2nd Embodiment. It is a figure for demonstrating the lamination | stacking order of the ink of 2nd Embodiment. It is the figure which illustrated the 1st unit lattice after ink discharge in a 2nd embodiment. It is explanatory drawing which shows schematic structure of the head part of 3rd Embodiment. It is a figure for demonstrating the lamination | stacking order of the ink of 3rd Embodiment. It is the figure which illustrated the 1st unit lattice after ink discharge of a 3rd embodiment. It is explanatory drawing which shows schematic structure of the head part of 4th Embodiment. It is a figure for demonstrating the lamination | stacking order of the ink of 4th Embodiment. It is a figure for demonstrating the lamination | stacking order of the ink of 5th Embodiment. It is explanatory drawing which shows schematic structure of the three-dimensional modeling apparatus in 6th Embodiment.

A1. First embodiment:
FIG. 1 is an explanatory diagram showing a schematic configuration of a three-dimensional modeling apparatus as a first embodiment of the present invention. The three-dimensional modeling apparatus 100 includes a modeling unit 10, a powder supply unit 20, a flattening mechanism 30, a powder recovery unit 40, a head unit 50, a curing energy application unit 60, and a control unit 70. I have. A computer 200 is connected to the control unit 70. The three-dimensional modeling apparatus 100 and the computer 200 can be combined and understood as a three-dimensional modeling apparatus in a broad sense. FIG. 1 shows an X direction, a Y direction, and a Z direction orthogonal to each other. The Z direction is a direction along the vertical direction, and the X direction is a direction along the horizontal direction. The Y direction is a direction perpendicular to the Z direction and the X direction.

  The modeling unit 10 is a tank-shaped structure in which a three-dimensional object is modeled. The modeling unit 10 includes a flat modeling stage 11 along the XY direction, a frame 12 that surrounds the modeling stage 11 and is erected in the Z direction, and an actuator 13 that moves the modeling stage 11 along the Z direction. Is provided. The modeling stage 11 moves in the Z direction within the frame 12 by the control unit 70 controlling the operation of the actuator 13.

  The powder supply unit 20 is a device that supplies powder into the modeling unit 10. The powder supply unit 20 is configured by, for example, a hopper or a dispenser.

  The flattening mechanism 30 flattens the powder supplied in the modeling unit 10 or on the frame body 12 by moving the upper surface of the modeling unit 10 in the horizontal direction (XY direction), and powders on the modeling stage 11. It is a mechanism for forming a body layer. The flattening mechanism 30 is configured by, for example, a squeegee or a roller. The powder pushed out from the modeling unit 10 by the flattening mechanism 30 is discharged into a powder recovery unit 40 provided adjacent to the modeling unit 10.

  The three-dimensional modeling apparatus 100 according to the first embodiment uses a curable liquid (hereinafter referred to as “curing liquid”) and the above-described powder as the material of the three-dimensional object. As the curable liquid, a liquid resin material mainly composed of a monomer and an oligomer to which the monomer is bonded, and a polymerization initiator that is excited when irradiated with ultraviolet light to start the polymerization by acting on the monomer or oligomer. A mixture with is used. In addition, a monomer having a relatively low molecular weight is selected as the monomer in the curable liquid so that the curable liquid can be discharged as droplets from the head unit 50, and the monomer contained in one oligomer is further selected. Is adjusted to about several molecules. When this polymerization solution is exposed to ultraviolet light and the polymerization initiator is in an excited state, the monomers are polymerized to grow into oligomers, and the oligomers also polymerize in various places to quickly cure and become solid. Have.

  In the present embodiment, a powder having a surface on which a polymerization initiator of a type different from that contained in the curable liquid is used is used as the powder. The polymerization initiator attached to the surface of the powder has the property of initiating polymerization by acting on a monomer or oligomer when it comes into contact with the curable liquid. For this reason, when the curable liquid is supplied to the powder in the modeling part 10, the curable liquid penetrates into the interior of the powder and is cured by contact with the polymerization initiator on the powder surface. As a result, the curable liquid is discharged. In such a portion, the powders are in a state of being bonded by the cured liquid. In addition, when using the powder by which the polymerization initiator adhered to the surface as a powder, it is also possible to use the hardening liquid which does not contain a polymerization initiator.

  The head unit 50 is a device that receives the above-described curable liquid supplied from a tank 59 connected to the head unit 50 and discharges the curable liquid to the powder layer in the modeling unit 10 along the Z direction. In the present embodiment, the head unit 50 can eject achromatic ink without color and a plurality of types of chromatic ink with color as the curable liquid. The head unit 50 is movable in the X direction and the Y direction with respect to the three-dimensional object that is modeled in the modeling unit 10. The head unit 50 is movable in the Z direction relative to the three-dimensional object by moving the modeling stage 11 in the modeling unit 10 in the Z direction.

  The head unit 50 of the present embodiment is a so-called piezo drive type droplet discharge head. A piezo-driven droplet discharge head fills the pressure chamber with fine nozzle holes with a hardening liquid and deflects the side wall of the pressure chamber using a piezo element, thereby reducing the volume of the pressure chamber. A corresponding volume of the curable liquid can be discharged as droplets. The control unit 70 to be described later can adjust the amount of the curable liquid ejected from the head unit 50 by controlling the voltage waveform applied to the piezo element.

  The curing energy application unit 60 is an apparatus for applying energy for curing the curable liquid discharged from the head unit 50. In the present embodiment, the curing energy application unit 60 includes a main curing light-emitting device 61 and a temporary curing light-emitting device 62 that are disposed so as to sandwich the head unit 50 in the X direction. When the head unit 50 moves, the curing energy application unit 60 also moves accordingly. The main curing light-emitting device 61 and the temporary curing light-emitting device 62 are irradiated with ultraviolet rays as curing energy for curing the curable liquid. The temporary curing light-emitting device 62 is used to perform temporary curing for fixing the discharged curing liquid to the landing position. The main curing light-emitting device 61 is used to completely cure the curable liquid after temporary curing. The energy of the ultraviolet rays irradiated from the temporary curing light emitting device 62 is, for example, 20 to 30% energy of the ultraviolet rays irradiated from the main curing light emitting device 61.

  The control unit 70 includes a CPU and a memory. The CPU loads the computer program stored in the memory or the recording medium into the memory and executes it, whereby the actuator 13, the powder supply unit 20, the flattening mechanism 30, the head unit 50, and the curing energy application unit. And a function of modeling a three-dimensional object. Although details will be described later, in this function, the space of the unit cell UG is controlled by controlling the head unit 50 to eject chromatic ink and achromatic ink into a unit cell UG (see FIG. 4) described later. The function of filling the volume with these inks is included. Note that these functions may be realized by an electronic circuit.

  FIG. 2 is an explanatory diagram showing a schematic configuration of the head unit 50. In the present embodiment, the head unit 50 ejects transparent (CL) ink as achromatic ink, cyan (C) ink, magenta (M) ink, and yellow (Y) ink as chromatic ink. Can do. In addition, the color of the ink which the head part 50 discharges is not restricted to these. For example, the head unit 50 may be configured to discharge white (W) or black (BK). The head unit 50 includes a first nozzle group 51 and a second nozzle group 52 that discharge droplets of transparent (CL) ink, a third A nozzle group 53 that discharges droplets of cyan (C) ink, and magenta ( M) a third B nozzle group 54 that ejects ink droplets, a third C nozzle group 55 that ejects yellow (Y) ink droplets, and a fourth nozzle group 56 that ejects transparent (CL) ink droplets. And the fifth nozzle group 57 are arranged in this order in the main scanning direction (X direction). In order to distinguish the transparent ink ejected from the nozzle groups 51, 52, 56, and 57 from each other, hereinafter, the transparent ink ejected from the first nozzle group 51 is also referred to as “first clear ink CL1”. The transparent ink ejected from 52 is also referred to as “second clear ink CL2”, the transparent ink ejected from the fourth nozzle group 56 is also referred to as “third clear ink CL3”, and the transparent ink ejected from the fifth nozzle group 57. The ink is also referred to as “fourth clear ink CL4”. The nozzle groups 53, 54, and 55 that discharge chromatic ink are collectively referred to as a “third nozzle group GN3”. The type of chromatic ink ejected from the third nozzle group GN3 is not limited to the above. In each nozzle group 51 to 57, a plurality of nozzles Nz are arranged in a zigzag shape along the sub-scanning direction (Y direction). In each nozzle group 51 to 57, the nozzles Nz may be arranged in a straight line.

  A method for modeling (manufacturing) a three-dimensional object by the three-dimensional modeling apparatus 100 (FIG. 1) will be briefly described. First, the computer 200 slices polygon data representing the shape of a three-dimensional object according to the Z-direction modeling resolution (stacking pitch), and generates a plurality of cross-sectional data along the XY directions. This cross-sectional data has a predetermined modeling resolution in the X direction and the Y direction, and stores the type and amount of the curable liquid (chromatic ink and achromatic ink) discharged to the XY coordinates corresponding to each element. Represented by the generated two-dimensional bitmap data. That is, in the present embodiment, the coordinates for discharging the curable liquid and the type and amount of the curable liquid to be discharged are specified to the control unit 70 of the three-dimensional modeling apparatus 100 by the bitmap data.

  When acquiring the cross-sectional data from the computer 200, the control unit 70 of the three-dimensional modeling apparatus 100 controls the powder supply unit 20 and the flattening mechanism 30 to form a powder layer in the modeling unit 10. Then, according to the cross-sectional data, the head unit 50 is driven to discharge the curable liquid onto the powder layer, and then the curing energy applying unit 60 is controlled toward the discharged curable liquid to irradiate ultraviolet light, Perform main curing. Then, the curable liquid is cured by ultraviolet light and the powders are bonded to each other, and a cross-sectional body corresponding to the cross-sectional data for one layer is formed in the modeling unit 10. When the cross section for one layer is thus formed, the control unit 70 drives the actuator 13 to lower the modeling stage 11 along the Z direction by the stacking pitch corresponding to the modeling resolution in the Z direction. When the modeling stage 11 is lowered, the control unit 70 forms a new powder layer on the cross-section already formed on the modeling stage 11. When the new powder layer is formed, the control unit 70 receives the next cross-sectional data from the computer 200, discharges the curable liquid onto the new powder layer, and irradiates the ultraviolet light, thereby forming a new cross-sectional body. Form. As described above, when the control unit 70 receives the cross-sectional data of each layer from the computer 200, the control unit 70 controls the actuator 13, the powder supply unit 20, the flattening mechanism 30, the head unit 50, and the curing energy application unit 60 to control one layer. Three-dimensional objects are formed by forming cross-sectional bodies one by one and stacking them.

  FIG. 3 is a specific flowchart of the three-dimensional modeling process executed in the present embodiment. In the present embodiment, first, the computer 200 acquires polygon data representing the shape of a three-dimensional object from a recording medium, a network, an application program executed on the computer 200, or the like (step S10). When the polygon data is acquired, the computer 200 separates the image of the surface of each polygon represented by the polygon data into C, M, and Y (step S20).

  When the image of the surface of each polygon is separated, the computer 200 then slices the polygon data according to the modeling resolution in the Z direction, and generates bitmap data for each cross section (step S40). At this time, the computer 200 sets the gradation values of chromatic colors (C, M, Y) to the coordinates corresponding to the outermost circumference of the cross-section (outermost circumference coordinates) based on the surface image of each polygon. Stores the value to represent. A value for ejecting clear ink is stored in the coordinates inside the outermost peripheral coordinates.

  When bitmap data is generated for each cross section, the control unit 70 of the three-dimensional modeling apparatus 100 receives the bitmap data from the computer 200 and controls each unit such as the head unit 50 according to the received bitmap data. Then, a three-dimensional object is modeled (step S50). As described above, gradation values for chromatic colors (C, M, Y) are recorded in the outermost peripheral coordinates of each cross-sectional data, and clear ink is ejected to the inner coordinates of the outermost peripheral coordinates. Stores the value to do. Therefore, in step S50, an object that is transparent inside and colored near the surface is formed. In step S50, the control unit 70 models a three-dimensional object according to the following method.

  FIG. 4 is a diagram for explaining a method of modeling a three-dimensional object. Upon receiving the bitmap data, the control unit 70 controls the head unit 50 to designate the designated type of curable liquid (at least one of chromatic ink and achromatic ink) at the coordinates designated in the bitmap data. Discharge only the specified amount. In other words, the control unit 70 controls the head unit 50 to discharge the curable liquid and form an object for each unit cell UG constituting the virtual three-dimensional cell DL shown in FIG. The unit cell UG here is a virtual three-dimensional region having a minimum spatial volume according to the modeling resolution in the X direction and the Y direction of the cross section and the stacking interval in the Z direction of the cross section. One unit cell UG corresponds to one coordinate of the bitmap data. Based on the first layer cross-sectional data (bitmap data), the control unit 70 completes the first layer cross-section by discharging the curable liquid to the unit cell UG constituting the first layer of the three-dimensional lattice DL. Then, based on the cross-sectional data of the second layer, the curable liquid is discharged to the unit cell UG constituting the second layer to complete the cross-section for the second layer. By repeating this up to the Nth layer, a three-dimensional object as a laminate is formed. The unit cell UG is also referred to as a voxel. In the case of this embodiment in which an object is shaped using powder, the space volume of the unit cell UG is a volume obtained by subtracting the volume of the powder contained therein from the volume of the unit cell UG. The curable liquid is discharged so as to almost fill the volume.

  According to the gradation values of each color of C, M, and Y recorded in the outermost peripheral coordinates of each cross-sectional data, the head unit 50 is a unit cell corresponding to the outer surface of the object (see FIG. 4B). The chromatic color ink designated to each of the first unit cell UGs and the second unit cell UGb) is ejected. Here, the first unit cell UGs is a unit cell corresponding to the side surface of the object, and the hatched portion in FIG. 4B represents the outer surface of the object. The second unit cell UGb is a unit cell corresponding to the bottom surface of the object, and the bottom surface of the second unit cell UGb constitutes the bottom surface of the object. Both the first unit cell UGs and the second unit cell UGb correspond to the outermost peripheral coordinates of the bitmap data. In the present embodiment, the head unit 50 ejects chromatic ink to the first and second unit cells UGs and UGb, and only achromatic ink to the unit cell UG inside the first and second unit cells UGs and UGb. Since the ejection is performed, an inner part surrounded by the first and second unit cells UGs and UGb is transparent, and a colored object is formed on the surface portion corresponding to the first and second unit cells UGs and UGb.

  FIG. 5 is a view for explaining the stacking order of the ink ejected from the head unit 50 in the first unit cell UGs. The head unit 50 of the present embodiment is configured to be able to eject chromatic color ink and achromatic color ink to the first unit cell UGs in both the forward path and the return path in the main scanning direction. Further, the head unit 50 is configured to be able to fill one first unit cell UGs with chromatic color ink and achromatic color ink by only one of the forward path and the return path. 5A shows the stacking order of the ink ejected in the forward path of the head unit 50 in the first unit cell UGs, and FIG. 5B shows the first order of the ink ejected in the return path. The stacking order within one unit cell UGs is shown. As shown in FIGS. 5A and 5B, the head unit 50 includes nozzle groups 51, 52, 56, and 57 that discharge clear ink on both sides of the third nozzle group GN3 that discharges chromatic ink. The clear ink can be ejected onto the upper portion of the chromatic ink ejected to the first unit cell UGs in one pass in both the forward path and the backward path. The effect of ejecting clear ink on top of chromatic ink will be described later. Here, the “upper part” means the + Z direction, which is the same as the stacking direction of the ink ejected into the one unit cell UGs.

  The control unit 70 according to the present embodiment determines the ejection amount of chromatic ink to be ejected into the first unit cell UGs according to the magnitude of the gradation value in the bitmap data. The control unit 70 adjusts the discharge amount of the clear ink CL according to the discharge amount of the chromatic color ink, and fills the space volume of the first unit cell UGs with the chromatic color ink and the achromatic color ink. Therefore, the total volume of the ink ejected to the first unit cell UGs is the same regardless of the type and amount of the chromatic color ink ejected into the first unit cell UGs. In the forward path of the head unit 50, the total discharge amount of the cyan (C) ink and the first clear ink CL1 is constant with respect to the first unit grid UGs, and the magenta (M) ink and the second clear ink CL2 The clear inks CL1 to CL3 are discharged so that the total discharge amount becomes constant and the total discharge amount of the yellow (Y) ink and the third clear ink CL3 becomes constant. In addition, the control unit 70 discharges a predetermined amount of the fourth clear ink CL4 on the uppermost part of the first unit grid UGs in the forward path of the head unit 50. By the control of the control unit 70 described above, the total amount of ink ejected by the head unit 50 to the first unit cell UGs is constant and is equal to the spatial volume of the first unit cell UGs. Further, the clear ink (CL4) is always discharged on the upper portion of the chromatic color ink discharged to the first unit cell UGs. In the return path of the head unit 50, the control unit 70 makes the total discharge amount of the yellow (Y) ink and the fourth clear ink CL4 constant with respect to the first unit grid UGs, and the magenta (M) ink and the third unit UGs. The clear inks CL2 to CL4 are discharged so that the total discharge amount of the clear ink CL3 is constant and the total discharge amount of the cyan (C) ink and the second clear ink CL2 is constant. Further, the control unit 70 discharges a predetermined amount of the first clear ink CL1 to the top of the first unit grid UGs in the return path of the head unit 50. Therefore, even in the return path, the total amount of ink ejected by the head unit 50 to the first unit cell UGs is constant, and is equal to the volume of the first unit cell UGs. Also, the clear ink (CL1) is necessarily discharged above the chromatic color ink discharged to the first unit cell UGs. Hereinafter, the volume filled by the total (constant) discharge amount of the set of chromatic color ink and achromatic color ink described above is also referred to as a sub-unit cell SU. The sub unit cell SU is also called a sub voxel, and in the present embodiment, one first unit cell UGs includes three sub unit cells SU. As described above, the control unit 70 associates each nozzle group that discharges clear ink with one type of chromatic color ink among the three types of chromatic color ink, and discharges a specific chromatic color ink. Is not filled with the space volume of the sub unit cell SU, the clear ink is ejected from the nozzle group associated with the chromatic color ink, and the volume of the sub unit cell SU is made up of the chromatic color ink and the clear ink. Fulfill. The control unit 70 also discharges the chromatic color ink and the achromatic color ink to the second unit cell UGb (FIG. 4) by the same procedure as that for the first unit cell UGs.

  FIG. 6 is a diagram illustrating the first unit cell UGs after each ink is ejected in the forward path. The color of the side surface of the object observed from the side surface side (Y direction side) of the first unit cell UGs is expressed by a combination of chromatic ink ejected to the first unit cell UGs. The head unit 50 according to the present embodiment sets the discharge amount per droplet of chromatic ink (C, M, Y) to “none (does not discharge)” according to the magnitude of the gradation value in the bitmap data. Select from “Small”, “Medium”, and “Large”. Specifically, the control unit 70 associates the gradation values in the bitmap data acquired from the computer 200 with the discharge rates of the ink colors “small”, “medium”, and “large”. Then, the head unit 50 is controlled so as to eject the ink amount determined by the dither matrix of each ink color. The ejection rate represents the probability that an ink droplet should be ejected onto the unit cell of that portion. In the present embodiment, when the ejection amount is “small”, the head unit 50 ejects 2 pl of chromatic ink, when “medium”, 4 pl of chromatic ink is ejected, and when “large”. 6 pl of chromatic ink is ejected. In the present embodiment, the discharge amount of each ink is divided into four stages, but may be more finely or roughly divided according to the discharge amount adjustment ability of the head unit 50.

When the discharge amount of the chromatic color ink is selected as described above based on the bitmap data, the control unit 70 sets the clear ink corresponding to the chromatic color ink according to the selected discharge amount of the chromatic color ink. Determine the amount of. As described above, the control unit 70 determines the discharge amount of each clear ink so that the total discharge amount of a specific set of chromatic color ink and clear ink is constant. Here, the sum of the discharge amounts of the chromatic color ink and the clear ink (volume of the sub unit cell SU) is 6 pl, and the amount of ink discharged when the discharge amount of the chromatic color ink is “large” Matches. In the following description, it is assumed that the volume of the first unit cell UGs is filled with 20 pl. The head unit 50 selects the amount of clear ink discharged per droplet from four types: “none (not ejected)”, “small”, “medium”, and “large”. The head unit 50 discharges 2 pl when the discharge amount of the first clear ink CL1 is “small”, discharges 4 pl when it is “medium”, and discharges 6 pl when it is “large”. To do. The head unit 50 ejects 2 pl of the fourth clear ink CL4 on the top of the first unit cell UGs. The configuration (type and amount) of ink in the first unit cell UGs shown in FIGS. 6A to 6D is as follows.
<Configuration of FIG. 6A>
CL1 “small” + CL2 “small” + C “medium” + M “medium” + Y “medium” + CL3 “small” + CL4 “small”
<Configuration of FIG. 6B>
CL1 “None” + CL2 “None” + C “Large” + M “Large” + Y “Large” + CL3 “None” + CL4 “Small”
<Configuration of FIG. 6C>
CL1 “None” + CL2 “Large” + C “Large” + M “None” + Y “Large” + CL3 “None” + CL4 “Small”
<Configuration of FIG. 6D>
CL1 “Large” + CL2 “Large” + C “None” + M “None” + Y “Small” + CL3 “Medium” + CL4 “Small”

  FIG. 7 is a diagram for explaining an example of the effect of the first embodiment. According to the three-dimensional modeling apparatus 100 of the present embodiment, the clear ink is ejected onto the upper portion of the chromatic ink ejected into the unit cell UG, so that the saturation of the chromatic color observed from the surface of the object is improved. Can do. Specifically, as shown in FIG. 7A, when the clear ink is stacked on the chromatic color ink, the chromatic color ink is spread in the horizontal direction by the clear ink. The spread at this time is the same spread as the chromatic color ink (FIG. 7B) having the same ink amount as the total ink amount of the discharged chromatic color ink and the clear ink. That is, according to the above configuration, even if the discharge amount of the chromatic color ink is small, the chromatic color ink can be further expanded by the clear ink, so that the saturation of the chromatic color can be improved.

  Further, according to the three-dimensional modeling apparatus 100 of the present embodiment, as shown in FIG. 6, the amount of the chromatic liquid that is discharged to the unit cell UG is adjusted in units smaller than the unit cell UG corresponding to the modeling resolution. Therefore, when forming a colored three-dimensional object, it is possible to suppress a decrease in the apparent resolution of the three-dimensional object as compared with the case where only one color is colored per unit cell UG. Further, in the present embodiment, when the space volume of the unit cell UG is not filled with the amount of the chromatic liquid ejected to the unit cell UG, the remaining space volume of the unit cell UG is filled with the achromatic color liquid. Therefore, the volume of each unit cell UG is made uniform, and a three-dimensional object can be accurately modeled.

  Further, according to the three-dimensional modeling apparatus 100 of the present embodiment, as shown in FIG. 2, the head unit 50 ejects clear ink on both sides of the third nozzle group GN3 that ejects chromatic color ink in the main scanning direction. Since the nozzle groups 51, 52, 56, and 57 are arranged, it is easy to clear the upper part of the chromatic ink ejected into the unit cell UG in both cases of the forward pass and the return pass at the time of scanning. Ink can be easily discharged.

A2. Modification of the first embodiment:
FIG. 8 is a diagram illustrating the first unit cell UGs after each ink is ejected in the forward path of the modification of the first embodiment. In the first embodiment, the control unit 70 has been described as ejecting clear ink on top of the chromatic color ink ejected to the first unit cell UGs in both the forward path and the return path of the head unit 50. The control unit 70 of the modification further discharges the clear ink to the first unit cell UGs before discharging the chromatic color ink to the first unit cell UGs, and applies the chromatic color ink to the upper part of the discharged clear ink. It is comprised so that it may discharge. That is, the control unit 70 is configured to discharge the clear ink to the first unit cell UGs both before and after discharging the chromatic color ink to the first unit cell UGs. For example, as shown in FIGS. 8A to 8D, the control unit 70 may be configured to surely discharge the first clear ink CL1 to the first unit cell UGs. Here, the volume of the first unit cell UGs is shown as being filled with 22 pl. The discharge amounts of the chromatic color ink and the clear ink discharged by the head unit 50 are the same as those in the first embodiment. The configuration (type and amount) of ink in the first unit cell UGs shown in FIGS. 8A to 8D is as follows.
<Configuration of FIG. 8A>
CL1 “Medium” + CL2 “Small” + C “Medium” + M “Medium” + Y “Medium” + CL3 “Small” + CL4 “Small”
<Configuration of FIG. 8B>
CL1 “small” + CL2 “none” + C “large” + M “large” + Y “large” + CL3 “none” + CL4 “small”
<Configuration of FIG. 8C>
CL1 “small” + CL2 “large” + C “large” + M “none” + Y “large” + CL3 “none” + CL4 “small”
Configuration of FIG. 8D>
CL1 “Large” + CL2 “Large” + C “None” + M “None” + Y “Small” + CL3 “Medium” + CL4 “Middle”

  According to the three-dimensional modeling apparatus 100 of the present embodiment, the chromatic color that is observed from the surface of the object in order to cause the first unit cell UGs to eject clear ink before the chromatic color ink is ejected to the first unit cell UGs. The saturation of can be improved. When the chromatic color ink is ejected on the upper portion of the clear ink, the chromatic color ink is pushed and spread in the horizontal direction by the clear ink, as in the case where the clear ink is ejected on the upper portion of the chromatic color ink. Therefore, the saturation of the chromatic color can be improved even if the discharge amount of the chromatic color ink is small. Further, as shown in FIG. 2, the head unit 50 includes nozzle groups 51, 52, 56, and 57 that discharge clear ink on both sides of the third nozzle group GN3 that discharges chromatic ink in the main scanning direction. Therefore, it is possible to easily discharge the chromatic color ink on the upper part of the clear ink discharged into the unit cell UG in both cases of the forward pass and the return pass at the time of scanning.

B. Second embodiment:
FIG. 9 is an explanatory diagram showing a schematic configuration of the head unit 50A of the second embodiment. The head unit 50A of the second embodiment is different from the head unit 50 (FIG. 2) of the first embodiment in that the number of nozzle groups that eject clear ink is two fewer. The head unit 50A includes a first nozzle group 51A that discharges a first clear (CL1) ink droplet, a second A nozzle group 52A that discharges a cyan (C) ink droplet, and magenta (M) ink. A second B nozzle group 53A for ejecting droplets, a second C nozzle group 54A for ejecting yellow (Y) ink droplets, a third nozzle group 55A for ejecting second clear (CL2) ink droplets, Are arranged in this order in the main scanning direction (X direction). The nozzle groups 52 </ b> A to 54 </ b> A that discharge chromatic ink are collectively referred to as “second nozzle group GN <b> 2”.

  FIG. 10 is a view for explaining the stacking order of the ink ejected from the head unit 50A of the second embodiment in the first unit cell UGs. Similarly to the head unit 50 of the first embodiment, the head unit 50A of the second embodiment can fill the first unit cell UGs with chromatic ink and achromatic ink by only one of the forward path and the return path. It is configured. FIG. 10A shows the stacking order of the ink ejected in the forward path of the head unit 50A in the first unit cell UGs, and FIG. 10B shows the first order of the ink ejected in the return path. The stacking order within one unit cell UGs is shown. As shown in FIGS. 10A and 10B, the head portion 50A includes nozzle groups 51A and 55A that discharge clear ink on both sides of the second nozzle group GN2 that discharges chromatic color ink. In any of the cases, the clear ink can be ejected onto the upper portion of the chromatic color ink ejected to the first unit cell UGs in one pass. Further, the control unit 70 adjusts the ejection amount of the clear ink CL in accordance with the amount of chromatic ink ejected to the first unit grid UGs, and the spatial volume of the first unit grid UGs is set to the chromatic color ink and the achromatic color. Fill with ink. Therefore, the total volume of the ink ejected to the first unit cell UGs is all the same.

FIG. 11 is a diagram illustrating the first unit cell UGs after ink is ejected in the outward path of the head unit 50A of the second embodiment. As in the first embodiment, the description will be made assuming that the volume of the first unit cell UGs is filled with 20 pl. The head unit 50A of the second embodiment differs from the head unit 50 of the first embodiment in the discharge amount of the clear ink CL. The discharge amount of the chromatic color ink is the same as that in the first embodiment. That is, the head portion of the second embodiment discharges 2 pl when the discharge amount of the chromatic color ink is “small”, discharges 4 pl when it is “medium”, and discharges it when it is “large”. Dispense 6 pl. The head portion 50A discharges 4 pl when the discharge amount of the first clear ink CL1 is “small”, discharges 6 pl when it is “medium”, and discharges 10 pl when it is “large”. . The head portion 50A discharges 2 pl when the discharge amount of the second clear ink CL2 is “small”, discharges 8 pl when it is “medium”, and discharges 10 pl when it is “large”. The configuration of the ink in the first unit cell UGs shown in FIGS. 11A to 11D is as follows.
<Configuration of FIG. 11A>
CL1 “Medium” + C “Medium” + M “Medium” + Y “Medium” + CL2 “Small”
<Configuration of FIG. 11B>
CL1 “None” + C “Large” + M “Large” + Y “Large” + CL2 “Small”
<Configuration of FIG. 11C>
CL1 “Medium” + C “Medium” + M “None” + Y “Small” + CL2 “Medium”
<Configuration of FIG. 11D>
CL1 “Large” + C “None” + M “None” + Y “Small” + CL2 “Medium”

  According to the second embodiment described above, the number of nozzle groups that eject clear ink is not limited to that of the first embodiment. For example, even in the head unit 50A of the second embodiment shown in FIG. 9, nozzle groups 51A and 55A that discharge clear ink are arranged on both sides of the second nozzle group GN2 that discharges chromatic ink in the main scanning direction. Therefore, the clear ink can be easily ejected on the upper part of the chromatic color ink ejected into the unit cell in both the forward path and the backward path during scanning.

C. Third embodiment:
FIG. 12 is an explanatory diagram showing a schematic configuration of the head unit 50B of the third embodiment. The head unit 50B of the third embodiment differs from the head unit 50 (FIG. 2) of the first embodiment in the position of the nozzle group that ejects clear ink. The head portion 50B includes a first nozzle group 51B that discharges a first clear (CL1) ink droplet, a second nozzle group 52B that discharges a cyan (C) ink droplet, and a second clear (CL2). A third nozzle group 53B that ejects ink droplets, a fourth nozzle group 54B that ejects magenta (M) ink droplets, and a fifth nozzle group 55B that ejects third clear (CL3) ink droplets And a sixth nozzle group 56B for discharging yellow (Y) ink droplets and a seventh nozzle group 57B for discharging fourth clear (CL4) ink droplets in the main scanning direction (X direction). They are arranged in order.

  FIG. 13 is a diagram for explaining the stacking order of the ink ejected from the head unit 50B of the third embodiment in the first unit cell UGs. Similarly to the head unit 50 of the first embodiment, the head unit 50B of the third embodiment can fill the first unit cell UGs with chromatic ink and achromatic ink by only one of the forward path and the return path. It is configured. FIG. 13A shows the stacking order of the ink ejected in the forward path of the head unit 50B in the first unit cell UGs, and FIG. 13B shows the first order of the ink ejected in the return path. The stacking order within one unit cell UGs is shown. As shown in FIGS. 13A and 13B, the head portion 50B includes nozzle groups 51B, 53B, and 55B that discharge clear ink on both sides of the nozzle groups 52B, 54B, and 56B that discharge chromatic ink. 57B is provided. Therefore, the clear ink can be ejected on the upper part of the chromatic color ink ejected to the first unit grid UGs in one pass in both the forward path and the return path. Further, with the above configuration, it is possible to suppress the chromatic inks ejected to the first unit cell UGs from contacting each other. When different types of chromatic color inks come into contact with each other in the stacking direction, color mixing (bleeding) may occur between the inks in contact with each other, and the saturation may decrease. According to this embodiment, since the upper part and the lower part of the chromatic color ink are easily in contact with the clear ink, the contact between the chromatic color inks can be reduced. Thereby, it is possible to make it difficult for the saturation to decrease due to color mixing.

  As in the first embodiment, the control unit 70 of the third embodiment sets the discharge amount of the cyan (C) ink and the first clear ink CL1 with respect to the first unit grid UGs in the forward path of the head unit 50. The total is constant, the total discharge amount of magenta (M) ink and second clear ink CL2 is constant, and the total discharge amount of yellow (Y) ink and third clear ink CL3 is constant. Ink is ejected. In addition, the control unit 70 discharges a predetermined amount of the fourth clear ink CL4 on the uppermost part of the first unit grid UGs in the forward path of the head unit 50. In the return path of the head unit 50, the control unit 70 makes the total discharge amount of the yellow (Y) ink and the fourth clear ink CL4 constant with respect to the first unit cell UGs, and the magenta (M) ink and the third unit UGs. Each ink is ejected so that the total ejection amount of the clear ink CL3 is constant and the total ejection amount of the cyan (C) ink and the second clear ink CL2 is constant. Further, the control unit 70 discharges a predetermined amount of the first clear ink CL1 to the top of the first unit grid UGs in the return path of the head unit 50. That is, the control unit 70 causes each ink to be ejected so as to fill the space volume of the sub unit lattice SU by the sum of the ejection amounts of the set of chromatic color ink and clear ink described above.

FIG. 14 is a diagram illustrating the first unit cell UGs after each ink is ejected in the outward path of the head unit 50B of the third embodiment. As in the first embodiment, the description will be made assuming that the volume of the first unit cell UGs is filled with 20 pl. The head unit 50B of the third embodiment is the same as the head unit 50 of the first embodiment except for the ejection order when each ink is ejected to the first unit cell UGs. The configuration of the ink in the first unit cell UGs shown in FIGS. 14A to 14D is as follows.
<Configuration of FIG. 14A>
CL1 “Small” + C “Medium” + CL2 “Small” + M “Medium” + CL3 “Small” + Y “Medium” + CL4 “Small”
<Configuration of FIG. 14B>
CL1 “None” + C “Large” + CL2 “None” + M “Large” + CL3 “None” + Y “Large” + CL4 “Small”
<Configuration of FIG. 14C>
CL1 “None” + C “Large” + CL2 “Large” + M “None” + CL3 “None” + Y “Large” + CL4 “Small”
<Configuration of FIG. 14D>
CL1 “Large” + C “None” + CL2 “Large” + M “None” + CL3 “Medium” + Y “Small” + CL4 “Small”

  According to the third embodiment described above, the position of the nozzle group that discharges the clear ink is not limited to the first embodiment. For example, even in the head unit 50B of the third embodiment shown in FIG. 12, a nozzle group 51B that discharges clear ink to both sides of each of the nozzle groups 52B, 54B, and 56B that discharge chromatic ink in the main scanning direction. , 53B, 55B, and 57B, the clear ink can be easily ejected onto the upper part of the chromatic ink ejected into the unit cell in both the forward path and the backward path during scanning.

D. Fourth embodiment:
FIG. 15 is an explanatory diagram illustrating a schematic configuration of a head unit 50C according to the fourth embodiment. Compared with the head unit 50 (FIG. 2) according to the first embodiment, the head unit 50C according to the fourth embodiment includes two nozzle groups that discharge white (W) ink, and discharges clear ink. The difference is that the number of nozzle groups to be reduced is two. The head portion 50C includes a first nozzle group 51C that discharges a first white (W1) ink droplet, a second nozzle group 52C that discharges a first clear (CL1) ink droplet, and cyan (C). A third A nozzle group 53C that ejects ink droplets, a third B nozzle group 54C that ejects magenta (M) ink droplets, a third C nozzle group 55C that ejects yellow (Y) ink droplets, A fourth nozzle group 56C that ejects droplets of the second clear (CL2) ink and a fifth nozzle group 57C that ejects droplets of the second white (W2) ink are arranged in the main scanning direction (X direction). They are arranged in order. The nozzle groups 53C to 55C that discharge chromatic ink are collectively referred to as “third nozzle group GN3B”.

  FIG. 16 is a diagram for explaining the stacking order of the ink ejected from the head unit 50C of the fourth embodiment in the first unit cell UGs and in the third unit cell UGn. The head unit 50C ejects inks respectively designated in two unit lattices (UGs and UGn) arranged continuously in a direction (depth direction) from the surface side to the inside side of the object. Here, the first unit cell UGs is a unit cell corresponding to the side surface of the object. In FIG. 16A, the left side of the first unit cell UGs corresponds to the outer surface of the object. The third unit cell UGn is located on the side opposite to the outer surface of the object of the first unit cell UGs (the right side in FIG. 16A), and along the X or Y direction with the first unit cell UGs. It is a unit cell lined up. The head unit 50C is configured to be able to fill the first unit cell UGs with chromatic ink and clear ink and fill the third unit cell UGn with white (W) ink by only one of the forward path and the return path. Yes. FIG. 16A shows the stacking order of the ink ejected in the forward path of the head unit 50B in the first unit cell UGs and the third unit cell UGn, and FIG. 16B shows the return path. The stacking order of the ink ejected in the first unit cell UGs and the third unit cell UGn is shown. As shown in FIGS. 16A and 16B, the head portion 50C includes nozzle groups 52C and 56C that discharge clear ink on both sides of the third nozzle group GN3B that discharges chromatic ink, and therefore, the forward path In both the return path and the return path, the clear ink can be discharged onto the top of the chromatic color ink discharged to the first unit cell UGs in one pass. In addition, since the head unit 50C includes the nozzle groups 51C and 57C that discharge white ink, the third unit cell UGn positioned inside the first unit cell UGs can be filled with the white ink. According to the fourth embodiment, in the object, the portion colored with the white ink is arranged inside the outer surface colored with the chromatic color ink. Thereby, since a ground color turns into white, the reproducibility of the color of the colored outer surface can be improved.

E. Fifth embodiment:
FIG. 17 is a diagram for explaining the stacking order of the ink ejected from the head unit 50D of the fifth embodiment in the first unit cell UGs. The head unit 50D of the fifth embodiment differs from the head unit 50C (FIG. 15) of the fourth embodiment in the position of the nozzle group that ejects white (W) ink. The head unit 50D includes a first nozzle group 51D that discharges a first clear (CL1) ink droplet, a second nozzle group 52D that discharges a cyan (C) ink droplet, and a first white (W1). A third nozzle group 53D that ejects ink droplets, a fourth nozzle group 54D that ejects magenta (M) ink droplets, and a fifth nozzle group 55D that ejects second white (W2) ink droplets. And a sixth nozzle group 56D that discharges yellow (Y) ink droplets and a seventh nozzle group 57D that discharges second clear (CL2) ink droplets in the main scanning direction (X direction). They are arranged in order. Similarly to the head unit 50C of the fourth embodiment, the head unit 50D of the fifth embodiment fills the first unit lattice UGs with the chromatic color ink and the clear ink by only one of the forward path and the return path, and the third unit The lattice UGn can be filled with white (W) ink. FIG. 17A shows the stacking order of the ink ejected in the forward path of the head unit 50D in the first unit cell UGs and the third unit cell UGn, and FIG. The stacking order of the ink ejected in the first unit cell UGs and the third unit cell UGn is shown. As shown in FIGS. 17A and 17B, the head portion 50D includes nozzle groups 51D and 57D that discharge clear ink on both sides of the nozzle groups 52D, 54D, and 56D that discharge chromatic color ink. In both the return path and the return path, the clear ink can be discharged onto the top of the chromatic color ink discharged to the first unit cell UGs in one pass. The head unit 50D includes nozzle groups 53D and 55D that discharge white ink between the nozzle groups 52D, 54D, and 56D that discharge chromatic color ink. Therefore, white ink can be discharged between different chromatic inks. By this white ink, it is possible to prevent the colors of different chromatic inks from interfering with each other. Further, since the head unit 50D includes the nozzle groups 53D and 55D that discharge white ink, the third unit cell UGn positioned inside the first unit cell UGs can be filled with the white ink. As a result, the portion colored by the white ink is arranged inside the outer surface of the object colored by the chromatic color ink, so that the color reproducibility of the colored outer surface can be improved.

F. Sixth embodiment:
FIG. 18 is an explanatory diagram illustrating a schematic configuration of the three-dimensional modeling apparatus according to the sixth embodiment. The three-dimensional modeling apparatus 100 according to the first embodiment models a three-dimensional object by discharging a curable liquid to the powder supplied into the modeling unit 10. On the other hand, the three-dimensional modeling apparatus 100E of the sixth embodiment models a three-dimensional object using only a curable liquid containing a resin without using powder.

  The three-dimensional modeling apparatus 100 </ b> E includes a modeling unit 10, a head unit 50, a curing energy application unit 60, and a control unit 70. The modeling unit 10 includes a modeling stage 11, a frame body 12, and an actuator 13 as in the first embodiment. However, the frame 12 may be omitted. A tank 59 is connected to the head unit 50. The curing energy application unit 60 includes a light-emitting device 61 for main curing and a light-emitting device 62 for temporary curing. That is, the 3D modeling apparatus 100E is common to the configuration of the 3D modeling apparatus 100 of the first embodiment in many parts, and is flat with the powder supply unit 20 from the 3D modeling apparatus 100 of the first embodiment. The configuration is such that the forming mechanism 30 and the powder recovery unit 40 are omitted. Even in such a three-dimensional modeling apparatus 100E, a three-dimensional object can be modeled by the same process as the three-dimensional modeling apparatus 100 of the first embodiment, except for the process of forming a powder layer. In the case of the present embodiment, the chromatic color ink and the achromatic color ink are ejected into the space volume of the unit cell UG so as to be substantially equal to the volume of the unit cell UG.

G. Variations:
<First Modification>
In the above-described embodiment, the three-dimensional modeling apparatus 100 colored the outermost periphery of the three-dimensional object. However, clear ink for protecting the colored portion may be discharged further to the outer peripheral side of the colored portion. .
<Second Modification>
Not only in the fourth and fifth embodiments, but also in the first to third embodiments, a value for ejecting white ink may be stored in the inner coordinates adjacent to the outermost peripheral coordinates of the bitmap data. If the white ink is arranged at the inner coordinates of the adjacent coordinates, the ground color becomes white, so that the reproducibility of the colored color can be improved. Further, the achromatic color ink disposed in the depth direction inner side than the chromatic color ink may be white ink instead of clear ink. If the achromatic ink disposed inside is a white ink, the ground color can be made white, so that the gradation expression using the chromatic ink can be performed more accurately.

<Third Modification>
The three-dimensional modeling apparatus 100 discharges chromatic ink to the first unit cell UGs (FIG. 4) to color only the side surface of the object, and the bottom surface of the object without discharging the chromatic color ink to the second unit cell UGb. The structure which does not perform coloring of may be sufficient. On the contrary, the bottom surface of the object may be colored and the side surface may not be colored.

<Fourth Modification>
The arrangement order of the nozzle groups that discharge chromatic ink shown in the present embodiment is an example, and is not limited to the example of the above embodiment. That is, in the above embodiment, the color of any chromatic color ink can be replaced with the color of any other chromatic color ink.

<Fifth Modification>
In the above embodiment, the head unit 50 relatively moves in the Z direction by moving the modeling stage 11 in the Z direction. On the other hand, the position of the modeling stage 11 may be fixed and the head unit 50 may be moved directly in the Z direction. Moreover, in the said embodiment, although the head part 50 moves to a X direction and a Y direction, even if it fixes the position of the X direction and the Y direction of the head part 50, and moves the modeling stage 11 to a X direction and a Y direction, Good.

<Sixth Modification>
In the above embodiment, among the three-dimensional modeling process shown in FIG. 3, the processes from Step S <b> 10 to Step S <b> 40 are executed by the computer 200. On the other hand, these processes may be executed by the 3D modeling apparatus 100. That is, the three-dimensional modeling apparatus 100 may execute all processes from acquisition of polygon data to modeling of a three-dimensional object as a single unit. Moreover, in the said embodiment, the process of step S50 shown in FIG. 3 is performed by the control part 70 of the three-dimensional modeling apparatus 100. FIG. On the other hand, the process of step S50 may be executed by the computer 200 controlling each part of the three-dimensional modeling apparatus 100. That is, the computer 200 may fulfill the function of the control unit 70 of the 3D modeling apparatus 100.

<Seventh Modification>
The configurations of the first to sixth embodiments can be appropriately combined. For example, a clear ink is ejected between nozzle groups that eject chromatic ink, as in the head unit 50B of the third embodiment shown in FIG. 12, with respect to the head unit 50C of the fourth embodiment shown in FIG. A nozzle group may be arranged. In addition, for example, the head unit 50D of the fifth embodiment shown in FIG. 17 performs the first operation before discharging chromatic ink to the first unit cell UGs as in the modification of the first embodiment shown in FIG. Clear ink may be ejected onto one unit cell UGs, and chromatic ink may be ejected on top of the ejected clear ink.

  The present invention is not limited to the above-described embodiments and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments and modifications corresponding to the technical features in each embodiment described in the summary section of the invention are intended to solve part or all of the above-described problems, or In order to achieve part or all of the effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 10 ... Modeling part 11 ... Modeling stage 12 ... Frame 13 ... Actuator 20 ... Powder supply part 30 ... Flattening mechanism 40 ... Powder collection part 50, 50A-D ... Head part 51-56, 51A-55A, 51B- 57B, 51C to 57C, 51D to 57D ... Nozzle group 59 ... Tank 60 ... Curing energy application unit 61 ... Main curing light emitting device 62 ... Temporary curing light emitting device 70 ... Control unit 100, 100E ... Three-dimensional modeling device 200 ... Computer GN ... Nozzle group Nz ... Nozzle DL ... Three-dimensional lattice UG ... Unit lattice SU ... Sub unit lattice

Claims (8)

A three-dimensional modeling apparatus that stacks a plurality of cross-sectional bodies in the Z direction to model a three-dimensional object,
Liquid that becomes the material of the object for each unit cell determined according to the modeling resolution in the X direction of the cross section, the modeling resolution in the Y direction of the cross section, and the stacking interval of the cross sections in the Z direction A head part for forming the object by discharging
The head unit includes a plurality of nozzle groups for ejecting the liquid, and a plurality of types of achromatic liquids and a plurality of types for indicating a specified color are displayed for one unit cell while scanning in a predetermined direction. Each of the chromatic liquids can be discharged in a specified amount, and the achromatic liquid is discharged to both sides of the plurality of nozzle groups that discharge the plurality of types of chromatic liquids in the main scanning direction of the head unit. A three-dimensional modeling apparatus in which nozzle groups are respectively arranged. The three-dimensional modeling apparatus according to claim 1 further includes:
A control unit for controlling the head unit;
The control unit controls the head unit to discharge the chromatic liquid onto the unit cell, and then discharges the achromatic liquid onto the upper portion of the discharged chromatic liquid in the Z direction. Original modeling device. The three-dimensional modeling apparatus according to claim 2,
The control unit controls the head unit to discharge the achromatic color liquid to the unit cell before discharging the chromatic color liquid to the unit cell, and to discharge the achromatic color liquid in the Z direction. A three-dimensional modeling apparatus that discharges the chromatic liquid at an upper part. The three-dimensional modeling apparatus according to claim 2 or 3, wherein
The unit cell has a plurality of sub-unit cells,
The head portion is configured such that the number of nozzle groups that discharge the achromatic liquid is equal to or greater than the number of nozzle groups that discharge the plurality of types of chromatic liquids.
Each nozzle group that discharges the achromatic color liquid is associated with one different chromatic color liquid among the plurality of types of chromatic color liquid,
The control unit controls the head unit to discharge the specific chromatic color liquid to be discharged to one unit cell when the specific chromatic color does not satisfy the spatial volume of the sub unit cell. A three-dimensional modeling apparatus that discharges the achromatic liquid from a group of nozzles of the achromatic color associated with the liquid and fills the subunit cell with the specific chromatic color liquid and the achromatic color liquid. The three-dimensional modeling apparatus according to any one of claims 2 to 4,
The head portion includes a nozzle group for discharging a white liquid,
The achromatic liquid is a colorless liquid,
The control unit controls the head unit so that the second unit cell adjacent to each other in the direction from the surface of the object to the inside is within the first unit cell positioned on the surface side of the object. A three-dimensional modeling apparatus that discharges a chromatic liquid and the colorless liquid, and discharges the white liquid into a second unit cell located on the inner side of the object. A three-dimensional modeling apparatus that stacks a plurality of cross-sectional bodies in the Z direction to model a three-dimensional object,
Liquid that becomes the material of the object for each unit cell determined according to the modeling resolution in the X direction of the cross section, the modeling resolution in the Y direction of the cross section, and the stacking interval of the cross sections in the Z direction A head part for shaping the object by discharging
A control unit for controlling the head unit,
The head unit can discharge a specified amount of achromatic liquid and a plurality of types of chromatic liquids for representing a specified color, with respect to one unit cell,
The control unit controls the head unit to discharge the achromatic color liquid to the unit cell before discharging the chromatic color liquid to the unit cell, and to discharge the achromatic color liquid in the Z direction. A three-dimensional modeling apparatus that discharges the chromatic liquid on an upper portion and discharges the achromatic liquid on an upper portion in the Z direction of the discharged chromatic liquid. A manufacturing method for manufacturing a three-dimensional object by a three-dimensional modeling apparatus that models a three-dimensional object by stacking a plurality of cross-sectional bodies in the Z direction,
The three-dimensional modeling apparatus, for each unit lattice determined according to the modeling resolution in the X direction of the cross-sectional body, the modeling resolution in the Y direction of the cross-sectional body, and the stacking interval in the Z direction of the cross-sectional body, A head part for forming the object by discharging a liquid as a material of the object;
The head unit is capable of discharging a specified amount of achromatic liquid and a plurality of types of chromatic liquids for representing a specified color with respect to one unit cell. In the main scanning direction of the unit, nozzle groups that discharge the achromatic liquid are respectively disposed on both sides of the plurality of nozzle groups that discharge the plurality of types of chromatic liquid,
The manufacturing method of controlling the head unit to discharge the chromatic liquid onto the unit cell and then discharging the achromatic liquid onto the upper portion of the discharged chromatic liquid in the Z direction. A computer program for manufacturing a three-dimensional object by controlling a three-dimensional modeling apparatus that forms a three-dimensional object by stacking a plurality of cross-sectional bodies in the Z direction,
The three-dimensional modeling apparatus, for each unit lattice determined according to the modeling resolution in the X direction of the cross-sectional body, the modeling resolution in the Y direction of the cross-sectional body, and the stacking interval in the Z direction of the cross-sectional body, A head part for forming the object by discharging a liquid as a material of the object;
The head unit is capable of discharging a specified amount of achromatic liquid and a plurality of types of chromatic liquids for representing a specified color with respect to one unit cell. In the main scanning direction of the unit, nozzle groups that discharge the achromatic liquid are respectively disposed on both sides of the plurality of nozzle groups that discharge the plurality of types of chromatic liquid,
Controlling the head unit to cause the computer to realize a function of discharging the chromatic liquid onto the unit cell and then discharging the achromatic liquid onto the upper portion of the discharged chromatic liquid in the Z direction. Computer program for.

Images