JP7144242B2 - Molded object manufacturing method - Google Patents

Description

The present invention relates to a method for manufacturing various shaped objects using, for example, a photosensitive slurry. For example, in fields such as medicine and aviation, it can be applied to development and manufacturing by a three-dimensional (3D) additive manufacturing method such as optical additive manufacturing.

2. Description of the Related Art Conventionally, two methods are known as a three-dimensional layered manufacturing method (more specifically, a slurry photocuring type layered manufacturing method) in which a modeled object is manufactured by irradiating a slurry containing a photolithographic material with light.
For example, a tank method is known in which the process of curing an arbitrary portion of the slurry in the tank by exposing it to a laser beam or the like, changing the height of the tank, and then curing the arbitrary portion again by a laser beam or the like is repeated. there is

In addition, the slurry is applied on the modeling stage, the slurry is flattened to the desired thickness with a blade or the like, an arbitrary portion is exposed to laser light and cured, and the slurry is applied again and then cured. It has been known.

Among these, with regard to the technique of the coating method, for example, as a method of manufacturing an artificial bone made of hydroxyapatite, a technique of manufacturing porous artificial bone by irradiating a laser beam to a slurry-like photofabrication material to harden it has been proposed. (See Patent Document 1).

JP 2012-232023 A

By the way, for example, when a slurry containing ceramics is used and a slurry photocuring type additive manufacturing method is used to manufacture a complicated three-dimensional shaped object (for example, a ceramic member), there are the following problems. .

Specifically, for example, when manufacturing a complicated three-dimensional shaped article having an overhang, first, the slurry is sequentially cured by a slurry photocuring type additive manufacturing method to prepare a cured product, and then, A modeled object is manufactured by placing a cured product on a baking base and then baking it.

However, in the case of a model having overhangs, there is a problem that the overhangs are pulled downward by gravity and deformed during firing. In addition, the problem of deformation of the model becomes more pronounced as the size of the model increases, and a countermeasure has been desired.

In addition, when manufacturing a three-dimensional modeled object made of resin or metal, a support member that supports the overhang from below may be used. At present, sufficient consideration has not been given to the case of manufacturing a modeled object by fabricating and baking the cured product.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for manufacturing a model that can suppress deformation of the model when firing a cured product produced by a three-dimensional layered manufacturing method. is to provide

(1) In a first aspect of the present invention, a three-dimensional surface is formed by repeating a step of forming a slurry layer on a base using a slurry and a step of hardening a part of the slurry layer to form a hardened layer. By the laminate manufacturing method (that is, the three-dimensional laminate manufacturing method) for producing the cured product, the grounding portion that contacts the base and the overhanging portion that projects outside the grounding portion in a plan view seen from above the base and a method for producing a shaped article, which comprises producing the cured product having the above and then baking the cured product to produce the shaped article.

In this method for manufacturing a modeled article, the cured product is produced on the base by the lamination molding method, and the surface of the overhanging portion on the base side and the surface of the base are brought into contact with each other to form the above-described molded article. A step of producing a composite cured product in which the cured product and the lower support portion are integrated by producing a lower support portion that supports the projecting portion; and after separating the composite cured product from the base. , baking the composite cured product to produce a composite modeled article; and removing the baked lower support portion from the composite modeled article to produce the modeled article. .

In the first aspect, the composite cured product is formed with a lower support portion that supports the overhang by contacting the surface of the base on the side of the base of the overhang and the surface of the base. , the projecting portion can be supported from below by the lower support portion. Therefore, since it is possible to suppress the overhanging portion from hanging downward during firing, it is possible to effectively suppress deformation of the overhanging portion during firing (thus, deformation of the molded article after firing).

(2) In the second aspect of the present invention, an upper support portion may be produced as part of the composite cured product on the upper surface of the projecting portion by the laminate manufacturing method, and then the baking may be performed.
In the second aspect, since the upper support part is produced on the upper surface of the projecting part, the upper support part functions as a weight. That is, since the upper support part presses the overhanging part from above when the overhanging part is fired, deformation of the overhanging part (in particular, deformation such that the outer peripheral side of the overhanging part is bent upward) is effectively suppressed. be able to.

(3) In the third aspect of the present invention, the upper support portion has an upper connecting portion that contacts the projecting portion, and the cross-sectional area of the upper connecting portion in the horizontal direction is greater than the upper connecting portion. It may be smaller than the horizontal cross-sectional area of the portion.

In the third aspect, since the cross-sectional area of the upper connecting portion is smaller than the cross-sectional area of the portion above the upper connecting portion, the strength of the upper connecting portion is lower than that of the upper portion. Therefore, after firing the composite cured product, the fired upper support portion can be easily separated at the fired upper connecting portion.

(4) In the fourth aspect of the present invention, the fired upper support portion may be removed from the composite modeled article.
This fourth aspect exemplifies a preferred manufacturing procedure for the shaped article.

(5) In the fifth aspect of the present invention, the lower support portion has a lower connecting portion that contacts the projecting portion, and the cross-sectional area of the lower connecting portion in the horizontal direction is lower than the lower connecting portion. It may be smaller than the horizontal cross-sectional area of the portion.

In the fifth aspect, since the cross-sectional area of the lower connecting portion is smaller than the cross-sectional area of the portion below the lower connecting portion, the strength of the lower connecting portion is lower than that of the lower portion. Therefore, after baking the composite cured product, the baked lower support portion can be easily separated at the baked lower connecting portion.

(6) In the sixth aspect of the present invention, in the step of manufacturing the composite modeled article, when the cured product is placed on a firing base, the lower support portion is a base that contacts the firing base. A side connecting portion may be provided, and the horizontal cross-sectional area of the base side connecting portion may be smaller than the horizontal cross-sectional area of the portion above the base side connecting portion.

In the sixth aspect, the cross-sectional area of the base-side connecting portion of the lower support portion is smaller than the cross-sectional area of the portion above the base-side connecting portion. Therefore, when the composite cured product is placed on a baking base (for example, a baking setter) and baked, even if the composite cured product shrinks due to baking (thus, even if the lower support part moves so as to slide) ), and the sliding resistance between the lower support portion and the firing base is small. Therefore, there is an effect that it is possible to suppress deformation of the composite cured product during firing (thus, the molded product after firing).

(7) In the seventh aspect of the present invention, the ground contact portion is produced by the laminate manufacturing method, and a lower side having a hardness lower than that of the composite cured product is formed outside the ground contact portion and the lower support portion in plan view. A low hardness support may be produced.

For example, when using a slurry with thixotropic properties in which ceramic particles are dispersed, for example, when producing a cured product by a three-dimensional layered manufacturing method such as a slurry photocuring type layered manufacturing method, when recoating the slurry (for example, a blade etc. When the slurry is applied many times using a recoating method, the cured portion of the slurry may swell excessively because both the cured portion and the uncured portion exist on the surface to be recoated with the slurry. In this case, since the excessively raised portion is also hardened, the hardened portion may collapse when the blade comes into contact with the raised hardened portion.

On the other hand, in the present seventh aspect, a low hardness lower hardness than the composite cured product is provided outside the ground contact portion and the lower support portion, which are hardened portions (for example, on the entire circumference of the ground contact portion and the lower support portion in the radial direction). Since the support portion is produced, it is possible to prevent the portion that becomes the contact portion and the lower support portion from being excessively raised when the slurry is recoated. As a result, the blade is less likely to come into contact with the raised portion, and collapse of the ground contact portion and the lower support portion can be suppressed.

(8) In the eighth aspect of the present invention, an uncured portion may be provided between at least one of the ground contact portion and the projecting portion and the lower low-hardness support portion.
In the eighth aspect, since the uncured portion where the slurry is not cured is provided between the grounding portion and/or the projecting portion and the lower low-hardness support portion, after forming the composite cured product, it is unnecessary to The bent lower low-hardness support portion can be easily removed.

(9) In the ninth aspect of the present invention, the thickness of the unhardened portion between at least one of the grounding portion and the projecting portion and the lower low-hardness support portion is 0.2 mm to 0.5 mm. It can be a range.

If the thickness of the uncured portion, which is the gap between at least one of the grounding portion and the overhanging portion, and the lower low-hardness support portion exceeds 0.5 mm, the slurry will not flow in the gap during recoating of the slurry. may occur and the slurry in the cured portion may rise excessively.

On the other hand, in the ninth aspect, since the thickness of the uncured portion is 0.5 mm or less (preferably 0.3 mm or less), even with slurries of various viscosities, excessive slurry during recoating can be used. It can effectively prevent overheating.

By reducing the thickness of the uncured portion to 0.5 mm or less, for example, when using a base film (that is, a film laid under the slurry), it is possible to obtain a shape that has a small adhesive surface with the base film. When shaping the cured product, the effect of suppressing the displacement of the cured product can be obtained.

Further, when the thickness of the uncured portion is less than 0.2 mm, when the curing of the slurry progresses so as to enter the gap in the planar direction, the vertical direction, etc., the contact portion or the overhang portion (that is, the cured portion portion) and the lower low-hardness support portion are likely to be in a connected state. Therefore, separation after modeling may become difficult.

On the other hand, in the ninth aspect, since the thickness of the uncured portion is 0.2 mm or more, it is difficult for the contact portion or the projecting portion to be connected to the lower low-hardness support portion during modeling. . Therefore, separation after modeling is easy.

(10) In the tenth aspect of the present invention, the lower low-hardness support portion may be removed before the firing.
This tenth aspect exemplifies a preferred manufacturing procedure for the shaped article.

(11) In the eleventh aspect of the present invention, the composite cured product is produced by the laminate manufacturing method, and an upper low-hardness support portion having a lower hardness than the composite cured product is produced on the upper surface of the composite cured product. may

As described above, for example, when a cured product is produced using a slurry having thixotropic properties by, for example, a slurry photocuring type additive manufacturing method or the like, the cured portion of the slurry may swell excessively during recoating of the slurry. A blade may come into contact with the excessively raised hardened portion.

On the other hand, in the eleventh aspect, since the upper low-hardness support portion having a hardness lower than that of the composite cured product is produced outside the ground contact portion, which is the hardened portion, when the slurry is recoated, the portion that becomes the ground contact portion is formed. Excessive excitement can be suppressed. As a result, the blade is less likely to come into contact with the raised portion, and collapse of the contact portion can be suppressed.

(12) In the twelfth aspect of the present invention, an uncured portion may be provided between the composite cured product and the upper low-hardness support portion.
In the twelfth aspect, since an uncured portion, which is an uncured portion of the slurry, is provided between the composite cured product and the upper low-hardness support portion, after forming the composite cured product, the unnecessary upper low-hardness support parts can be easily removed.

(13) In the thirteenth aspect of the present invention, the thickness of the uncured portion between the composite cured product and the upper low-hardness support portion may be in the range of 0.2 mm to 0.5 mm.
When the thickness of the uncured portion, which is the gap between the composite cured product and the upper low-hardness support portion, exceeds 0.5 mm, the slurry flows in the gap during recoating of the slurry, and the slurry in the cured portion is sometimes overexcited.

On the other hand, in the thirteenth aspect, since the thickness of the uncured portion is 0.5 mm or less (preferably 0.3 mm or less), even with slurries of various viscosities, excessive slurry during recoating can be used. It can effectively prevent overheating.

Further, when the thickness of the uncured portion is less than 0.2 mm, when the curing of the slurry progresses so as to enter the gap in the planar direction, the vertical direction, etc., the composite cured product (that is, the cured portion) It is likely to be in a state of being connected with the upper low-hardness support portion. Therefore, separation after modeling may become difficult.

In contrast, in the thirteenth aspect, since the thickness of the uncured portion is 0.2 mm or more, it is difficult for the composite cured product and the upper low-hardness support portion to be connected to each other during modeling. Therefore, separation after modeling is easy.

(14) In the fourteenth aspect of the present invention, the upper low-hardness support portion may be removed before the firing.
This fourteenth aspect exemplifies a preferred manufacturing procedure for the shaped article.

(15) In the fifteenth aspect of the present invention, the slurry contains a solid component and a photocurable resin that constitute the modeled object, and the slurry layer is partially cured by irradiating the slurry layer with light. You may let

The fifteenth aspect exemplifies a method of producing a cured product using a slurry photocuring type additive manufacturing method.
<Each configuration of the present invention will be described below>
The slurry (mud) is a suspension in which solid particles are mixed in a liquid, and has the property that a part of the slurry is hardened by an external stimulus such as light or heat.

Examples of the liquid constituting the slurry (that is, the material that hardens) include photo- or thermosetting resins. Moreover, examples of the solids that constitute the slurry include ceramics.

- When the slurry has photosensitivity, a material that is cured by exposure (stereolithography material) is used as the material of the slurry. Examples of the stereolithography material include acrylic photocurable resins.

- When the slurry contains ceramics, examples of the ceramics include alumina, zirconia, and hydroxyapatite.
- The vertical dimension (thickness) of the upper connecting portion and the lower connecting portion is in the range of 300 µm ± 200 µm. Moreover, as a configuration of the upper connection portion and the lower connection portion, for example, a mesh structure or the like can be mentioned.

As for the shape of the base-side connecting portion, when viewed from the horizontal direction, a smoothly curved shape (for example, a hemispherical shape) that protrudes downward can be mentioned. In this case, the vertical cross-sectional shape of the base-side connecting portion cut in the vertical direction may be an R shape.

・In the composite cured product, the firing shrinkage behavior of the upper support part and lower support part and the cured part corresponding to the modeled object (for example, the cured part corresponding to the ground part and the overhang part: cured product) should be similar. is preferred. For example, the amounts of shrinkage of the upper and lower support portions and the cured product are preferably the same, or (upper support portion and lower support portion)≦(cured product).

・The blade is a blade-shaped or plate-shaped member capable of moving the slurry, and examples of materials thereof include metals such as stainless steel and synthetic resins such as urethane rubber.

It is a perspective view which shows the molded article in 1st Embodiment. While showing the apparatus etc. for producing the three-dimensional hardened|cured material of 1st Embodiment, it is explanatory drawing which fracture|ruptures and shows a lower support part and a lower low-hardness support part in an up-down direction. FIG. 4 is a plan view showing the arrangement of lower support portions in the composite cured product of the first embodiment; FIG. 2 is a vertically cut cross-sectional view showing the arrangement of the composite cured product, the lower low-hardness support portion, and the uncured portion in the three-dimensional cured product of the first embodiment. 4 is a flow chart showing part of the process of manufacturing a modeled object according to the first embodiment. It is explanatory drawing which shows the method of baking the composite hardened|cured material of 1st Embodiment. While showing the apparatus etc. for producing the three-dimensional hardened|cured material of 2nd Embodiment, it is explanatory drawing which fracture|ruptures and shows a lower support part and a lower low-hardness support part in an up-down direction. 8A is a cross-sectional view showing an enlarged cross section (longitudinal cross section) of the lower connecting portion of the composite cured product of the second embodiment, etc., FIG. 8B is an AA cross-sectional view of FIG. 8A, and FIG. It is sectional drawing which expands and shows a vertical cross section, such as a lower connection part of a modification. While showing the apparatus etc. for producing the three-dimensional hardened|cured material of 3rd Embodiment, it is explanatory drawing which fracture|ruptures and shows a lower support part and a lower low-hardness support part in an up-down direction. While showing the apparatus etc. for producing the three-dimensional hardened|cured material of 4th Embodiment, it is explanatory drawing which fracture|ruptures and shows a lower support part, an upper support part, and an up-and-down low hardness support part in an up-down direction. It is a top view which shows arrangement|positioning of the upper support part in the composite hardened|cured material of 4th Embodiment. FIG. 12A is a sectional view showing an enlarged longitudinal section of the upper support portion of the fourth embodiment, and FIG. 12B is a sectional view showing an enlarged longitudinal section of the upper support portion of the modification. FIG. 13A is a sectional view showing a longitudinal section of the three-dimensional cured product etc. of the fifth embodiment, and FIG. 13B is a sectional view showing a longitudinal section of the three-dimensional cured product etc. of the sixth embodiment.

Next, an embodiment of a method for manufacturing a modeled article according to the present invention will be described.
[1. First Embodiment]
Here, for example, a method for manufacturing a modeled object having a predetermined shape by curing a photocurable resin using a laser beam will be described as an example.
[1-1. Structure of model]
First, the structure of the model manufactured by the manufacturing method of the model according to the first embodiment will be described.

As shown in FIG. 1, a three-dimensional (three-dimensional) shaped object 1 manufactured by the method for manufacturing a shaped object according to the first embodiment is a sintered body made of ceramic such as alumina. It comprises a flat plate member 3 having a circular shape (when viewed from the vertical direction in FIG. 2) and a grounding member 5 supporting the flat plate member 3 from below.

The grounding member 5 includes a shaft member 7 coaxial with the center of the axis of the flat plate member 3 and extending in the vertical direction, and a base member 9 provided below the shaft member 7 and having a circular flat plate shape in plan view. A projecting portion 11 is a portion of the flat plate member 3 that projects outward from the grounding member 5 (specifically, the shaft member 7 ) in a plan view.

For example, the modeled object 1 has a height of 50 mm, the flat plate member 3 has a diameter of 80 mm×thickness of 5 mm, the shaft member 7 has a diameter of 5 mm×length of 40 mm, and the base member 9 has a diameter of 20 mm×thickness of 5 mm.
[1-2. Modeled product manufacturing method]
Next, a method for manufacturing the modeled object 1 according to the first embodiment will be described.

a) First, the outline of the manufacturing method of the molded article 1 will be described.
In the first embodiment, a photocurable slurry in which ceramic powder and photocurable resin are mixed is prepared as a material for the modeled object 1 .

Then, as will be described in detail later, a three-dimensional cured product 21 (see FIG. 2) having an intended shape was produced by a slurry photocuring type additive manufacturing method, which is a three-dimensional additive manufacturing method. The three-dimensional cured product 21 includes a composite cured product 27 composed of a cured product 23 and a lower support portion 25 and a lower low-hardness support portion 29, as shown in FIG.

That is, in the first embodiment, the three-dimensional cured product 21 in which the photocurable slurry is cured is produced using a well-known stereolithography apparatus 31 that irradiates the photocurable slurry with an ultraviolet laser beam for modeling. . Thereafter, the lower low-hardness support portion 29 was removed from the three-dimensional cured product 21 to produce a composite cured product 27, which was then fired. Then, the molded article 1 was manufactured by removing the baked lower support portion 25 from the baked composite cured product 27 .

Here, as will be described later, in the following Example 1, a modeling program was used to produce the desired modeling model (that is, the three-dimensional cured product 21) by the slurry photocuring layered modeling method. That is, as shown in FIG. 2, using modeling data of a three-dimensional cured product 21 having a cured portion (that is, a cured product 23) corresponding to the modeled object 1, a lower support portion 25, and a lower low-hardness support portion 29, , modeling was performed by curing the slurry with light. After that, only the lower low-hardness support portion 29 was removed from the three-dimensional cured product 21 shaped as described above, and degreasing and baking were performed.

In addition, in Comparative Example 1 below, the modeling data for producing the three-dimensional cured product 21 is the same as in Example 1, and both the lower support portion 25 and the lower low-hardness support portion 29 are removed after modeling and fired. did In Comparative Example 2, modeling was performed using only the modeling model of the cured product 23 and modeling data in which the lower support portion 25 and the lower low-hardness support portion 29 were not arranged.

b) Hereinafter, a detailed manufacturing method of the modeled object 1 will be described based on Example 1 and the like.
<Photocurable slurry>
First, a method for preparing a photocurable slurry will be described.

Alumina powder with an average particle size of 0.4 μm (Sumitomo Chemical Advanced Alumina AA-03), acrylic photocurable resin (for example, monofunctional or multifunctional alkyl acrylate, photoinitiator 1-hydroxy A mixture of cyclohexane phenyl ketone) was mixed so that the alumina powder was 55% and the photocurable resin was 45% by volume.

Next, the mixture was uniformly stirred with a rotation/revolution mixer to prepare a photocurable slurry (hereinafter sometimes simply referred to as slurry).
<Examples and Comparative Examples>
Next, Example 1 within the scope of the present invention using the slurry described above and Comparative Examples 1 and 2 outside the scope of the present invention will be described.

(Example 1)
(1) First, the photocurable slurry was set in a slurry supply device (not shown) of the stereolithography device 31 . Then, modeling data (i.e., modeling slice data) was prepared from the CAD data of the modeling model corresponding to the three-dimensional cured product 21 including the composite cured product 27 and the lower low-hardness support portion 29 shown in FIG. .

The modeling data was created so that the slice thickness was 100 μm, which is the thickness of one layer that is cured by light.
Here, the configuration of the three-dimensional cured product 21 produced by the modeling data described above will be described.

The composite cured product 27 is a cured portion composed of the cured product 23 and the lower support portion 25, and the degree of curing of the cured product 23 and the lower support portion 25 are the same.
The hardened product 23 is a portion that will become the molded product 1 including the flat plate member 3 and the grounding member 5 after firing. A portion of the cured product 23 corresponding to the flat plate member 3 is a flat plate portion 33 , and a portion corresponding to the grounding member 5 is a grounding portion 35 . The grounding portion 35 is composed of a shaft portion 37 corresponding to the shaft member 7 and a base portion 39 corresponding to the base member 9 .

A portion of the flat plate portion 33 that projects outward from the base portion 39 in plan view, that is, a portion that faces the base 41 on which the three-dimensional cured product 21 is formed is the projecting portion 43 .
The lower support portion 25 is a support member that supports from below a portion (that is, the protruding portion 43) that may be deformed during modeling (the stage up to hardening before firing) and during firing. , extending to reach the surface of the base 41 . The lower support portion 25 is, for example, cylindrical and has a diameter of, for example, 5 mm.

As shown in FIG. 3, the lower support portions 25 are arranged along the outer circumference of the overhanging portion 43, more specifically, slightly inside the outer circumference, at equal intervals in the circumferential direction (that is, at equal angles around the center of the axis). ) are arranged at, for example, eight locations.

Further, the lower low-hardness support portion 29 is a portion having a hardness lower than that of the composite cured product 27 . As shown in FIG. 4, the lower low-hardness support portion 29 is arranged so as to surround the entire periphery of the composite cured product 27 (excluding the upper surface). For example, the lower low-hardness support portion 29 is arranged radially outside the ground contact portion 35 and the lower support portion 25 .

The lower low-hardness support portion 29 is arranged with a slight gap from the composite cured product 27 . This gap is an unhardened portion 45 in which the slurry has not hardened, and the thickness of this gap (that is, the unhardened portion 45) is in the range of 0.2 mm to 0.5 mm (for example, 0.5 mm).

(2) Next, as shown in FIG. 2, one layer of slurry was supplied from the slurry supply device onto the base 41, which is the modeling stage, and applied. A base film may be placed on the base 41 and the slurry may be supplied onto the base film.

(3) Next, a well-known blade (not shown) was used to flatten the surface of the slurry. Specifically, the slurry was shaped by moving the blade so as to trace the surface of the slurry to flatten the surface of the slurry. The blade was moved along the surface of the base 41 (that is, parallel to the surface). As is well known, this yields one layer of slurry (not shown).

(4) Next, the surface of the slurry was irradiated with ultraviolet laser light (that is, scanned) to cure one layer of the desired three-dimensional cured product 21 . That is, by curing the photocurable resin with an ultraviolet laser beam, two types of cured portions with different hardness were formed as one cured layer (not shown) in the slurry layer.

Specifically, in order to form the composite cured product 27 having a high hardness, the slurry was irradiated with ultraviolet laser light under predetermined conditions (that is, conditions for applying high energy) at the locations where the composite cured product 27 was to be formed.

As a device for irradiating the ultraviolet laser light, for example, an ultraviolet laser device with an output of 0.5 W was used, and the ultraviolet laser light with a wavelength of 355 nm was applied. Laser irradiation was performed under the conditions of a spot diameter of 50 μm and a scanning speed of 1000 mm/sec.

In addition, in order to form the lower low-hardness support portion 29 having a lower hardness than the composite cured product 27, a predetermined condition (i.e., when forming the composite cured product 27 The slurry was irradiated with an ultraviolet laser beam under the condition of applying energy lower than that of the slurry.

For example, when forming the lower low-hardness support portion 29, the scanning speed of the ultraviolet laser beam was increased to 5000 mm/sec (other conditions were the same), and laser irradiation was performed.
As a method for changing the hardening state of the slurry, various methods can be adopted, for example, changing the state of the energy applied by the ultraviolet laser beam. For example, various methods can be adopted, such as a method of changing the output of the ultraviolet laser device, a method of changing the spot diameter, and a method of changing the overlapping width of adjacent regions when scanning.

After forming the cured portion in one slurry layer, the base 41 is lowered by one layer to form the next (that is, upper) slurry layer.
(5) Next, the slurry was supplied to the surface of the partially hardened slurry layer in the same manner as in step (2) above.

(6) Next, the surface of the supplied slurry was flattened using a blade in the same manner as in the step (3).
(7) Next, the planarized surface of the slurry was irradiated with ultraviolet laser light in the same manner as in the step (4) above to harden the irradiated portion.

After that, the steps (5) to (7) were repeated to produce the desired three-dimensional cured product 21 including the composite cured product 27 and the lower low-hardness support portion 29 (see S100 in FIG. 5). .
(8) Next, since the three-dimensional hardened material 21 obtained as described above exists in the unhardened slurry, the unhardened slurry is removed and the lower low-hardness support portion 29 was removed, and composite cured product 27 including cured product 23 and lower support portion 25 was taken out (see S200 in FIG. 5). The slurry adhering to the surface of the composite cured product 27 was removed by ultrasonic cleaning or the like.

(9) Next, as shown in FIG. 6, the composite cured product 27 was placed on a baking base 51, which is a baking setter. At this time, the lower surface of the ground portion 35 (specifically, the base portion 39 ) of the composite cured product 27 and the lower end of the lower support portion 25 are in contact with the upper surface of the firing base 51 .

Then, the composite cured product 27 was fired under predetermined firing conditions. As the firing conditions, a condition of firing at 1500° C. for 2 hours in an air atmosphere can be adopted.
As a result, a composite shaped article 53 in which the composite cured product 27 was fired was obtained (see S300 in FIG. 5).

Thereafter, the baked lower support portion 25 (that is, the lower molded article 55) was removed from the composite molded article 53 to obtain the molded article 1 having the intended shape (see S400 in FIG. 5).
(Comparative example 1)
In Comparative Example 1, the same modeling model (that is, three-dimensional cured product) as in Example 1 was produced in the same manner as in Example 1 above. Next, the lower low-hardness support portion was removed from the three-dimensional cured product to produce a composite cured product. Next, a cured product was produced by removing the lower support portion from the composite cured product.

Then, this cured product was baked in the same manner as in Example 1 to prepare a modeled article of Comparative Example 1.
(Comparative example 2)
In Comparative Example 2, in the same manner as in Example 1, a molded model of a cured product without the lower low-hardness support portion and the lower support portion was produced.
[1-3. evaluation]
Next, the evaluation of Example 1 and Comparative Examples 1 and 2 described above will be described.

Specifically, in Example 1 and Comparative Examples 1 and 2, it was examined whether or not a molded article having a desired shape (that is, the molded article shown in FIG. 1) was obtained.
In addition, the flatness of the obtained shaped article, more specifically, the flatness of the upper surface of the flat plate member was examined.

The results are shown in Table 1 below.

なお、表１の造形可否の「○」は、目視で目的とする形状の造形物が得られたことを示し、「×」は、変形が大きく目的とする形状の造形物が得られなかったことを示している。また、平面度が「○」とは、平面度が０．１ｍｍ未満を示し、「×」とは、平面度が０．１ｍｍ以上を示している。

In Table 1, "○" indicates that a modeled object with the desired shape was obtained by visual inspection, and "×" indicates that a modeled object with the desired shape was not obtained due to large deformation. It is shown that. In addition, the flatness “O” indicates that the flatness is less than 0.1 mm, and the “X” indicates that the flatness is 0.1 mm or more.

As is clear from Table 1, in Example 1, the target shape can be formed, and the flatness is small, which is preferable.
In other words, in the case of Example 1, no swelling occurred in the hardened portions (that is, the ground contact portion 35 and the lower support portion 25) of the model during the modeling. Therefore, the blade did not come into contact with the hardened portion during the molding, and the molding could be performed favorably. Further, since the projecting portion 43 is supported by the lower support portion 25 during firing, deformation of the projecting portion 43 can be suppressed. Therefore, the flatness could be reduced.

On the other hand, in Comparative Example 1, modeling was possible, but the flatness was large, which is not preferable.
That is, in the case of Comparative Example 1, no bulge occurred in the hardened portion of the model during modeling. However, since there is no lower support portion during firing, the overhanging portion cannot be supported from below, and deformation of the overhanging portion cannot be suppressed.

In addition, in Comparative Example 2, swelling occurred in the hardened portion of the model during modeling. As a result, the blade came into contact with the hardened portion during modeling and collapsed, making it impossible to continue modeling.
[1-4. effect]
Next, the effects of the first embodiment will be described.

(1) In the first embodiment, a modeling model (three-dimensional cured product 21 in this case) having a desired shape is produced using a slurry photocuring layered modeling method.
Specifically, a lower support portion 25 that supports the overhanging portion 43 by contacting the surface of the overhanging portion 43 on the base 41 side and the surface of the base 41 is formed, whereby the cured product 23 and the lower support are bonded together. A composite cured product 27 in which the portion 25 is integrated is produced. Next, after separating the composite cured product 27 from the base 41 , the composite cured product 27 is fired to produce a composite shaped article 53 . Next, the molded article 1 is manufactured by removing the baked lower support portion 25 (that is, the lower molded article 55 ) from the composite molded article 53 .

Thus, in the first embodiment, the composite cured product 27 includes a lower support portion that contacts the surface of the overhanging portion 43 on the base 41 side and the surface of the base 41 to support the overhanging portion 43. 25 is provided, the projecting portion 43 can be supported from below by the lower support portion 25 when baking the composite cured product 27 . Therefore, it is possible to suppress the overhanging portion 43 from sagging downward during firing, thereby effectively suppressing deformation of the overhanging portion 43 during firing (thus, deformation of the modeled object 1 after firing).

(2) In the first embodiment, when the composite cured product 27 is produced, a lower lower layer having a hardness lower than that of the composite cured product 27 is placed outside (thus around) the grounding portion 35 and the lower support portion 25 in plan view. A hardness support portion 29 is produced.

Therefore, when the slurry is recoated (that is, reapplied), it is possible to prevent the portion that becomes the grounding portion 35 and the lower support portion 25 from being excessively raised. As a result, the blade is less likely to come into contact with the raised portion, and collapse of the grounding portion 35 and the lower support portion 25 can be suppressed.

(3) In the first embodiment, an unhardened portion 45, which is an unhardened portion of slurry, is provided between the grounding portion 35, the projecting portion 43, the lower support portion 25, and the lower low-hardness support portion 29. Therefore, after forming the composite cured product 27, the unnecessary lower low-hardness support portion 29 can be easily removed.
[1-5. Correspondence of wording]
Here, the correspondence relationship between the wordings of the embodiment and the scope of claims will be described.

Modeled object 1 , cured product 23 , lower support portion 25 , composite cured product 27 , lower low-hardness support portion 29 , ground contact portion 35 , base 41 , projecting portion 43 , and uncured portion 45 of the first embodiment , the fired base 51, and the composite molded article 53 are the molded article, the cured article, the lower support section, the composite cured article, the lower low-hardness support section, the ground section, the base, the projecting section, and the un It corresponds to an example of a curing part, a baking base, and a composite model.
[2. Second Embodiment]
Next, the second embodiment will be described, but the description of the same contents as in the first embodiment will be omitted or simplified. In addition, the same numbers are used for the same configurations as in the first embodiment.

In the second embodiment, as in the first embodiment, a modeling model (that is, a three-dimensional cured product 21) having a desired shape is produced using a slurry photocuring type additive manufacturing method, and the three-dimensional cured product 21 A modeled object 1 is produced from

In the second embodiment, as shown in FIG. 7 , as in the first embodiment, the composite cured product 27 in the three-dimensional cured product 21 has such a shape that it reaches the base 41 from the lower surface side of the projecting portion 43 . A lower support portion 25 is provided.

In particular, in the second embodiment, the lower support portion 25 has a lower connecting portion 61 that contacts the projecting portion 43 . The horizontal cross-sectional area S1 of the lower connecting portion 61 is smaller than the horizontal cross-sectional area S2 of the portion below the lower connecting portion 61 .

Specifically, as shown in FIG. 8, the lower connecting portion 61 has a structure in which a plurality of columns are arranged so as to extend vertically in FIG. 8A. Therefore, the cross-sectional area S1 on the AA cross section is smaller than the cross-sectional area S2 on the solid portion (BB cross section) of the lower support portion 25 below it. Therefore, the strength of the lower connecting portion 61 having a small cross-sectional area is lower than that of its surrounding (upper or lower) portion before and after firing.

In addition, since the lower connecting portion 61 having a small cross-sectional area and the overhanging portion 43 are joined with an area smaller than the cross-sectional area S2, the joint strength is low. In addition, the lower connecting portion 61 may have a mesh structure in which gaps are provided in the pillars instead of the above-described structure in which a plurality of pillars are arranged.

The second embodiment has the same effect as the first embodiment.
In addition, in the second embodiment, the cross-sectional area S1 of the lower connecting part 61 is smaller than the cross-sectional area S2 below it. It can be easily separated at the portion of the lower connecting portion 61 after firing.

As a modification of the second embodiment, as shown in FIG. 8C, the diameter (thus the cross-sectional area) of the upper end portion of the lower support portion 25 is made smaller toward the upper end side (that is, the projecting portion 43 side). may
[3. Third Embodiment]
Next, the third embodiment will be described, but the description of the same contents as in the first embodiment will be omitted or simplified. In addition, the same numbers are used for the same configurations as in the first embodiment.

In the third embodiment, as in the first embodiment, a modeling model (that is, a three-dimensional cured product 21) having a desired shape is produced using a slurry photocuring type additive manufacturing method, and the three-dimensional cured product 21 A modeled object 1 is produced from

In the third embodiment, as shown in FIG. 9 , as in the first embodiment, the composite cured product 27 in the three-dimensional cured product 21 has such a shape that it reaches the base 41 from the lower surface side of the projecting portion 43 . A lower support portion 25 is provided.

In particular, in the third embodiment, the lower end side of the lower support portion 25 has a smaller cross-sectional area in the horizontal direction toward the lower end side (that is, the tip end side).
Specifically, the lower support part 25 has a base-side connecting part 65 on its lower end side that contacts the firing base 51 during firing, and the cross-sectional area S1 of the base-side connecting part 65 in the horizontal direction is It is smaller than the cross-sectional area S2 in the horizontal direction of the portion above the base-side connecting portion 65 .

That is, the base-side connecting portion 65 has a hemispherical shape on the lower end side (that is, the tip end side) and protrudes downward. In other words, when the lower support portion 25 is broken along the axial direction, the lower end side of the lower support portion 25 has an R shape that curves into a circular shape.

The third embodiment has the same effect as the first embodiment.
In addition, in the third embodiment, the lower end side of the lower support portion 25 has a hemispherical base-side connecting portion 65 whose cross-sectional area decreases toward the tip side. Therefore, when the composite hardened product 27 is placed on the baking base 51 and baked, even if the composite hardened product 27 shrinks (thus, even if the lower support part 25 slides), the lower part The sliding resistance between the support portion 25 and the firing base 51 is small. Therefore, there is an effect that the deformation of the composite cured product 27 during firing (therefore, the shaped article 1 after firing) can be suppressed.
[4. Fourth Embodiment]
Next, a fourth embodiment will be described, but descriptions of the same contents as in the first embodiment will be omitted or simplified. In addition, the same numbers are used for the same configurations as in the first embodiment.

In the fourth embodiment, similarly to the first embodiment, a modeling model having a desired shape is produced using the slurry photocuring layered modeling method, and the modeled object 1 is produced from the modeling model.
As shown in FIG. 10, in the fourth embodiment, as in the first embodiment, the composite cured product 27 is provided with a lower support portion 25 reaching the base 41 from the lower surface side of the projecting portion 43. ing.

In particular, in the fourth embodiment, an upper support portion 67 having the same configuration as the lower support portion 25 is provided on the upper surface of the flat plate portion 33 (specifically, the projecting portion 43).
This upper support portion 67 is a part of the composite cured product 27 and has the same composition and hardness as the composite cured product 27 . The upper support part 67 is produced by the same method as the lower support part 25 when producing the composite cured product 27 .

In addition, as shown in FIG. 11, the upper support part 67 is arranged above the eight lower support parts 25, for example.
Further, as shown in FIG. 10, on the upper surface of the composite cured product 27, more specifically, on the outer side of the upper support portion 67 in plan view, an upper low-hardness support portion 69 having a hardness lower than that of the composite cured product 27 is provided. there is The upper low-hardness support portion 69 has the same configuration as the lower low-hardness support portion 29 and is manufactured in the same manner as the lower low-hardness support portion 29 .

Furthermore, an unhardened portion 71, which is a gap where the slurry is not hardened, is also formed between the composite hardened material 27 and the upper low-hardness support portion 69, similarly to the unhardened portion 45 described above. The thickness of this gap (that is, the uncured portion 71) is in the range of 0.2 mm to 0.5 mm (for example, 0.5 mm).

The modeling model of the fourth embodiment includes the cured product 23, the lower support portion 25, and the lower low-hardness support portion 29, and the upper support portion 67 and the upper low-hardness support portion 69, which are the same as those of the first embodiment. It is a three-dimensional cured product 21 with In this case, the composite cured product 27 is composed of the cured product 23 , the lower support portion 25 and the upper support portion 67 .

In the fourth embodiment, after the three-dimensional cured product 21 is produced, the lower low-hardness support portion 29 and the upper low-hardness support portion 69 are removed to produce the composite cured product 27 . After baking the composite cured product 27 , the baked lower support part 25 and upper support part 67 are removed to obtain the modeled object 1 .

The fourth embodiment has the same effect as the first embodiment.
Further, in the fourth embodiment, an upper support portion 67 is provided on the upper surface of the projecting portion 43 . Therefore, when the composite hardened material 27 is baked, the upper support portion 67 presses the projecting portion 43 from above, causing deformation of the projecting portion 43 (in particular, deformation such that the outer peripheral side of the projecting portion 43 is bent upward). can be effectively suppressed.

In addition, since the upper surface of the composite cured product 27 is provided with the upper low-hardness support portion 69, when the upper support portion 67 is sequentially formed with slurry, the portion that will become the upper support portion 67 will not protrude excessively. There is no Therefore, the upper support portion 67 can be easily shaped.

Furthermore, in the fourth embodiment, since the uncured portions 45 and 71 are provided, the lower low-hardness support portion 29 and the upper low-hardness support portion 69 can be easily removed.
As a modification of the fourth embodiment, an upper support portion 67 having a cross-sectional shape (a shape broken in the vertical direction) as shown in FIG. 12A can be employed.

That is, the lower part of the upper support part 67 has an upper connecting part 73 that contacts the projecting part 43, and the cross-sectional area S1 of this upper connecting part 73 in the horizontal direction is the portion above the upper connecting part 73 ( It is smaller than the cross-sectional area S2 in the horizontal direction of the solid portion of the upper support portion 67). Therefore, the strength of the portion with a small cross-sectional area is low.

Therefore, after baking the composite cured product 27, the baked upper support part 67 (that is, the upper molded article 75) can be easily removed.
As a modification of the fourth embodiment, as shown in FIG. 12B, the diameter (thus the cross-sectional area) of the lower end portion of the upper support portion 67 may be made smaller toward the lower end.
[5. Fifth Embodiment]
Next, the fifth embodiment will be described, but the description of the same contents as in the first embodiment will be omitted or simplified. In addition, the same numbers are used for the same configurations as in the first embodiment.

As shown in FIG. 13A, the fifth embodiment has a cured product 81 that extends in an arcuate shape from a portion of the upper surface of the base 41 . A lower support portion 83 extending from the tip of the hardened material 81 and reaching another portion of the upper surface of the base 41 is also provided.

Further, a lower low-hardness support portion 85 is provided inside the cured product 81 and the lower support portion 83 , and an upper low-hardness support portion 87 is provided outside the cured product 81 and the lower support portion 83 .

Between the cured product 81/lower support portion 83 and the lower low-hardness support portion 85, and between the cured product 81/lower support portion 83 and the upper low-hardness support portion 87, an uncured portion 89 have.

Parts with names similar to those of the first embodiment are made of materials similar to those of the first embodiment and have similar functions.
The fifth embodiment has the same effect as the first embodiment.
[6. Sixth Embodiment]
Next, the sixth embodiment will be described, but the description of the same contents as in the first embodiment will be omitted or simplified. In addition, the same numbers are used for the same configurations as in the first embodiment.

As shown in FIG. 13B, in the sixth embodiment, a ground portion 91 is provided on a portion (for example, the central portion) of the upper surface of the base 41, and the top portion of the ground portion 91 has a central portion. has a flat plate portion 93 (therefore, an overhang portion 95) that is convex upward and curved in an arc shape. In other words, it has a substantially T-shaped cured product 97 with an arcuate tip end.

A lower support portion 99 extending downward from the projecting portion 95 and reaching the upper surface of the base 41 is provided on the outer peripheral side of the projecting portion 95 . Moreover, the upper surface of the projecting portion 95 has an upper support portion 101 extending upward.

Further, inside the hardened material 97 and the lower support part 99, there is a lower low-hardness support part 103, and an upper low-hardness support part 103 is provided so as to cover the hardened material 97, the lower support part 99 and the upper support part 101 from the outside. It has a hardness support portion 105 .

Between the cured product 97/lower support portion 99 and the lower low-hardness support portion 103, and between the cured product 97/lower support portion 99/upper support portion 101 and the upper low-hardness support portion 105 , and an uncured portion 107 .

Parts with names similar to those of the first embodiment are made of materials similar to those of the first embodiment and have similar functions.
The sixth embodiment has the same effect as the first embodiment.
[7. Experimental example]
Next, an experimental example will be described.

This experimental example confirms the effect of defining the thickness of the uncured portion.
In this experimental example, as in the first embodiment, a photocurable slurry in which ceramic powder and a photocurable resin are mixed is prepared, and the slurry is scanned using an ultraviolet laser device. A three-dimensional cured product with a similar shape was produced.

As a modeling program of an experimental example, in Example 2, in a modeling model corresponding to a three-dimensional cured product, the thickness of the gap (that is, the uncured portion) between the composite cured product and the lower low-hardness support portion is set to 0.3 mm. , and in Example 3 it was set to 0.5 mm. In Comparative Example 3, the thickness of the gap was set to 0.8 mm, and in Comparative Example 4, it was set to 0.1 mm.

In this experimental example, the thickness of the uncured portion of 0.2 mm to 0.5 mm was used as an example, and the other samples were used as a comparative example.
A detailed description will be given below.

<Preparation of photocurable slurry>
The photocurable slurry used in this experimental example was prepared by the following method.
Alumina powder having an average particle size of 0.4 μm and an acrylic photocurable resin, which are the same as in the first embodiment, were uniformly stirred and mixed in a rotation/revolution mixer at a predetermined volume ratio. Specifically, after mixing, the mixing ratio of the alumina powder and the acrylic photocurable resin is adjusted so that the viscosity at a shear rate of 1 s ⁻¹ becomes two types of viscosities, 40 Pa s and 200 Pa s. to prepare slurries of different viscosities.

<Preparation and evaluation of three-dimensional cured product>
(Example 2)
(1) First, as in the first embodiment, one of the photocurable slurries having different viscosities was set in the slurry supply section of the stereolithography apparatus. In addition, slice data for modeling of a modeling model corresponding to the three-dimensional cured product was prepared.

The data was created with a slice thickness of 100 μm during modeling. In addition, the drawing laser conditions were set so that the composite cured product (high hardness) and the lower low-hardness support portion (low hardness) were in an appropriate cured state. In addition, a lower low-hardness support portion was provided with a clearance of 0.3 mm with respect to the composite cured product.

(2) Next, slurry was applied to the modeling stage, the slurry was flattened with a blade, and scanning was performed with an ultraviolet laser beam under each laser drawing condition according to processing data.
Then, the modeling stage is lowered by the thickness of the slice (for example, 100 μm) until the next layer can be modeled as one cycle, and this cycle is repeated until a predetermined modeling height is reached to produce a three-dimensional cured product.

A three-dimensional cured product was produced in the same manner using photocurable slurries with different viscosities.
(3) As an evaluation of defects during modeling, unevenness occurs in the slurry during recoating, and the blade eventually contacts the hardened part corresponding to the composite cured product [F1]. The problem that the composite cured product and the lower low-hardness support portion are difficult to separate when removing is evaluated as a problem [F2].

Defect [F1] is used to determine whether or not a defect has occurred. For defect [F1], when unevenness occurs during recoating but the blade does not come into contact with the blade and molding is possible up to a predetermined number of layers, "defect [F1] △" is determined. A case where the hardened portion was raised by the blade and the blade came into contact with the blade was determined as "failure [F1] x". Regarding the defect [F2], the case where the composite cured product and the lower low-hardness support portion were difficult to separate was determined as "defect [F2] x". The results are shown in Table 2 below.

(Example 3)
In Example 3, the thickness of the gap between the composite cured product and the lower low-hardness support was set to 0.5 mm. The results are shown in Table 2 below.

(Comparative Example 3)
In Comparative Example 3, the thickness of the gap between the composite cured product and the lower low-hardness support was set to 0.8 mm. The results are shown in Table 2 below.

(Comparative Example 4)
In Comparative Example 4, the thickness of the gap between the composite cured product and the lower low-hardness support was set to 0.1 mm. The results are shown in Table 2 below.

この表２から明らかなように、間隙が０．３ｍｍの実施例２では、どちらの粘度のスラリーでも、スラリーの盛り上がりによるブレードの接触や、下部低硬度サポート部の除去困難などの不具合は発生しなかった。

As is clear from Table 2, in Example 2 with a gap of 0.3 mm, problems such as contact of the blade due to swelling of the slurry and difficulty in removing the lower low-hardness support portion did not occur with either slurry of viscosity. I didn't.

Further, in Example 3 in which the gap was 0.5 mm, blade contact failure occurred with high-viscosity slurry, but no failure occurred with low-viscosity slurry.
On the other hand, in Comparative Example 3 in which the gap was 0.8 mm, the problem of contact with the blade due to swelling occurred regardless of the viscosity of the slurry. Moreover, in Comparative Example 4 with a gap of 0.1 mm, it was difficult to remove the lower low-height support portion.
[8. Other embodiments]
The present invention is by no means limited to the embodiments described above, and it goes without saying that various aspects can be implemented without departing from the scope of the present invention.

(1) For example, in the above-described embodiment, a laser beam is used to manufacture a modeled object using a photocurable resin. good.
For example, a slurry containing a thermosetting resin may be heated by irradiating it with a laser beam using, for example, a CO ₂ laser, and a predetermined portion of the slurry may be cured by the heat to manufacture a modeled object.

(2) Ceramics to be added to the slurry is not limited to the alumina mentioned above, and zirconia, hydroxyapatite, silicon nitride, aluminum nitride, silicon carbide, etc. can be used.

(3) Further, the molded object to be manufactured includes an artificial bone, a cutting tool, a bearing member, an insulating member, a wear-resistant member, and the like, depending on the slurry material (for example, ceramic material).
(4) In addition, for example, a low-hardness support portion composed of a lower low-hardness support portion and an upper low-hardness support portion is provided so as to surround the composite hardened product including the ground portion, the lower support portion, and the upper support. may

(5) Furthermore, the shape, number, arrangement, etc. of the lower support part and the upper support part are limited to the above embodiments as long as they can suppress deformation of the flat part and the overhanging part during firing as described above. not to be

(6) It should be noted that the function of one component in each of the above embodiments may be assigned to a plurality of components, or the function of a plurality of components may be performed by one component. Also, part of the configuration of each of the above embodiments may be omitted. Also, at least a part of the configuration of each of the above embodiments may be added, replaced, or the like with respect to the configuration of another embodiment. In addition, every aspect included in the technical idea specified from the wording of the claim is an embodiment of the present invention.

DESCRIPTION OF SYMBOLS 1... Molded object 23, 81, 97... Cured material 25, 83... Lower support part 27... Composite hardened material 29, 87... Lower low-hardness support part 35, 91... Ground part 41... Base 43, 95... Overhang Part 45, 71, 89, 107 Uncured part 51 Firing base 53 Composite model 61 Lower connection part 65 Base side connection part 67, 87, 101 Upper support part 69, 87, 105 Upper side Low-hardness support part 73 ... Upper connecting part

Claims (14)

A step of forming a slurry layer on a base using a slurry, and a step of hardening a part of the slurry layer to form a hardened layer are repeated to produce a three-dimensional hardened product. Producing the cured product having a grounding portion that contacts the base and an overhanging portion that projects outside the grounding portion in a plan view seen from the base,
After that, in the method for manufacturing a modeled product by baking the cured product,
A lower support that forms the cured product on the base by the layered manufacturing method and supports the overhang by contacting the surface of the overhang on the side of the base and the surface of the base. A step of producing a composite cured product in which the cured product and the lower support part are integrated by producing a part;
After separating the composite cured product from the base, baking the composite cured product to produce a composite shaped article;
a step of removing the fired lower support portion from the composite model to produce the model;
has
By the layered manufacturing method, the grounding portion is produced, and a lower low-hardness support portion having a hardness lower than that of the composite cured product is produced outside the grounding portion and the lower support portion in the plan view,
A method of manufacturing a modeled object. A step of forming a slurry layer on a base using a slurry, and a step of hardening a part of the slurry layer to form a hardened layer are repeated to produce a three-dimensional hardened product. Producing the cured product having a grounding portion that contacts the base and an overhanging portion that projects outside the grounding portion in a plan view seen from the base,
After that, in the method for manufacturing a modeled article by baking the cured product to manufacture a modeled article,
A lower support that forms the cured product on the base by the layered manufacturing method and supports the overhang by contacting the surface of the overhang on the side of the base and the surface of the base. A step of producing a composite cured product in which the cured product and the lower support part are integrated by producing a part;
After separating the composite cured product from the base, baking the composite cured product to produce a composite shaped article;
a step of removing the fired lower support portion from the composite modeled article to produce the modeled article;
has
By the laminate manufacturing method, the composite cured product is produced, and an upper low-hardness support portion having a lower hardness than the composite cured product is produced on the upper surface of the composite cured product.
A method of manufacturing a modeled object. An upper support part is produced as part of the composite cured product on the upper surface of the overhanging part by the laminate molding method, and then the baking is performed.
3. The method for manufacturing the shaped article according to claim 1 or 2 . The upper support part has an upper connecting part that contacts the overhanging part, and the horizontal cross-sectional area of the upper connecting part is smaller than the horizontal cross-sectional area of the portion above the upper connecting part.
The manufacturing method of the modeled article according to claim 3 . removing the fired upper support portion from the composite-shaped article;
5. The method of manufacturing a modeled article according to claim 3 or 4 . The lower support part has a lower connecting part that contacts the overhanging part, and the horizontal cross-sectional area of the lower connecting part is smaller than the horizontal cross-sectional area of the portion below the lower connecting part.
A method for manufacturing a shaped article according to any one of claims 1 to 5 . In the step of producing the composite modeled article, when the cured product is placed on a baking base, the lower support part has a base side connecting part that contacts the baking base, and the base side The horizontal cross-sectional area of the connecting portion is smaller than the horizontal cross-sectional area of the portion above the base side connecting portion,
A method for manufacturing a shaped article according to any one of claims 1 to 6 . The slurry contains a solid component and a photocurable resin that constitute the modeled object,
irradiating the slurry layer with light to cure a portion of the slurry layer;
A method for manufacturing a shaped article according to any one of claims 1 to 7. An uncured portion is provided between at least one of the grounding portion and the projecting portion and the lower low-hardness support portion;
The manufacturing method of the modeled article according to claim 1 . The thickness of the unhardened portion between at least one of the grounding portion and the projecting portion and the lower low-hardness support portion is in the range of 0.2 mm to 0.5 mm.
The manufacturing method of the modeled article according to claim 9 . removing the lower low-hardness support portion before the firing;
11. The method of manufacturing a modeled article according to any one of claims 1, 9, and 10. An uncured portion is provided between the composite cured product and the upper low-hardness support portion;
3. The method of manufacturing a modeled article according to claim 2 . The thickness of the uncured portion between the composite cured product and the upper low-hardness support portion is in the range of 0.2 mm to 0.5 mm.
13. The method for manufacturing a modeled article according to claim 12. removing the upper low-hardness support portion before the firing;
14. The method of manufacturing a modeled article according to any one of claims 2, 12, and 13.

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