KR102219555B1 - Light polymerised 3d printing method using slurry having high viscosity - Google Patents

Abstract

The present invention relates to a photocurable 3D printing method using high-viscosity slurry, capable of outputting a three-dimensional structure having excellent quality. According to an aspect of the present invention, the photocurable 3D printing method using high-viscosity slurry comprises: a slurry providing step of providing photocurable 3D printing slurry containing a pigment and a photocurable resin to a stage; and a light irradiation step of irradiating light to the photocurable 3D printing slurry to form a cross-section of the structure and a cross-section of a partition wall spaced apart from the one cross-section of the structure.

Description

Photocuring 3D printing method using high viscosity slurry {LIGHT POLYMERISED 3D PRINTING METHOD USING SLURRY HAVING HIGH VISCOSITY}

The present invention relates to a photocurable 3D printing method using a high viscosity slurry, and more particularly, to a photocurable 3D printing method using a high viscosity slurry with improved output accuracy.

3D printing technology is a technology for printing a three-dimensional structure, and there are cutting type 3D printing that forms a three-dimensional structure by sculpting raw materials and a layered 3D printing technology that forms a structure by layering materials layer by layer. Since the stacked 3D printing technology is a method of stacking materials, it has a higher material use efficiency compared to cutting type 3D printing, and has the advantage of being able to form a sophisticated structure, thus attracting great attention as a next-generation process technology.

The layered 3D printing technology is based on the material lamination method: Material jetting, Material Extrusion, Binder jetting, Directed Energy Deposition, and Powder Bed Fusion. , Sheet Lamination, a photo-curing method (eg, stereolithography), etc. There are various methods.

In particular, in the case of the photo-curing method, a three-dimensional structure is printed by using light to cure photo-curable materials, and has an advantage of being able to output an elaborate structure with high resolution.

Photocuring 3D printing technology can be divided into a bottom-up method in which light is irradiated from bottom to top and a top-down method in which light is irradiated from top to bottom.

The bottom-up photocurable 3D printing is a method in which light passes through a translucent stage or tank and is irradiated onto photocurable materials, so the output accuracy and efficiency may be degraded due to scattering or reflection during the process of passing the light through the stage or tank. have.

On the other hand, top-down photo-curable 3D printing directly irradiates light onto photo-curable materials, and thus has superior output precision and efficiency compared to bottom-up photo-curable 3D printing.

In the top-down photo-curing 3D printing, a photo-curable material is provided on a stage in the form of a layer, and the cross-sections of the structure are formed by irradiating light to the photo-curing layer. In this case, a blade that provides a photocurable material to the stage in the form of a layer may be used. However, there may be a case in which the blade cannot apply the photocurable material to the stage with a uniform thickness. In particular, when the viscosity of the photocurable material is high, the flowability of the photocurable material deteriorates, and the thickness variation of the photocurable layer may be further increased due to the surface tension of the photocurable material and the blade. The thickness deviation of the photocurable layer is expressed as a thickness deviation of the cross section of the structure to be printed, leading to a problem of deteriorating the output precision of photocurable 3D printing.

Particularly, when a metal pigment or a ceramic pigment is added to the photocurable material, the viscosity of the photocurable material is inevitably increased, and the above-described problems may occur even more.

Accordingly, there is a need for a technique for solving the above-described problem.

Meanwhile, the above-described background technology is not necessarily a known technology disclosed to the general public prior to the filing of the present invention.

Korean Patent Publication No. 10-2019-0130456

An object of the present invention is to provide a photo-curing 3D printing method using a high viscosity slurry capable of outputting a three-dimensional structure having an elaborate, excellent quality.

As a technical means for achieving the above-described technical problem, according to an aspect of the present invention, a photocurable 3D printing method using a high viscosity slurry provides a slurry for providing a photocurable 3D printing slurry containing a pigment and a photocurable resin to a stage. And a light irradiation step of irradiating light to the photo-curable 3D printing slurry to form a cross-section of the structure and a cross-section of the partition wall spaced apart from the cross-section of the structure.

According to another aspect of the present invention, the step of providing the slurry includes providing the slurry for photocuring 3D printing to the stage in a layer form using a blade crossing the stage, and the light irradiation step And forming a section of the rear end partition wall at the rear of one section of the structure based on the moving direction of the blade.

According to another aspect of the present invention, the light irradiation step may further include forming a cross section of the shear partition wall in front of the cross section of the structure based on the moving direction of the blade.

According to another aspect of the present invention, the step of providing the slurry includes providing the slurry for photo-curing 3D printing to the stage in a layer form using a blade crossing the stage, and the light irradiation step May include forming an enclosing partition wall to surround one end face of the structure.

According to another aspect of the present invention, forming the enclosing partition wall so as to surround one end face of the structure may include forming the enclosing partition wall separated into a plurality of pieces.

According to another aspect of the present invention, one end face of the structure is spaced apart from the upper surface of the stage, and the light irradiation step includes forming a supporter connecting the end face of the structure and the stage. It may contain more.

According to another aspect of the present invention, the structure includes a cavity recessed from an uppermost end, and the light irradiation step includes the photocuring 3D printing so that the structure is output in an inclined state with respect to the stage. It may include forming a cross section of the inclined structure and a cross section of a partition wall spaced apart from the cross section of the structure by irradiating light to the solvent slurry.

According to another aspect of the present invention, the structure may be output in a state that is inclined with an inclination within 90° with respect to the stage.

According to another aspect of the present invention, one cross-section of the partition wall may be spaced from 0.01 to 10 mm from the outline of the cross-section of the structure.

According to another aspect of the present invention, the photocurable 3D printing slurry may be a high viscosity slurry having a viscosity of 5000cp or more.

According to any one of the above-described problem solving means of the present invention, an embodiment of the present invention solves the problem of rounding or thickness non-uniformity occurring in the process of applying a high-viscosity slurry using a partition wall formed to be spaced apart from one end surface of the structure. And, through this, it is possible to provide a photocurable 3D printing method with improved precision.

In addition, according to any one of the problem solving means of the present invention, the sagging of the sections of the structure can be minimized by using a partition wall formed to be spaced apart from one section of the structure, and the supporter for suppressing the sagging of the sections of the structure is minimized. Through this, it is possible to provide a photocurable 3D printing method with improved precision.

In addition, according to any one of the problem solving means of the present invention, by outputting a structure having a cavity in an inclined state, and by using a partition wall spaced apart from one cross section of the structure, outputting cross sections of the inner shape of the cavity It is possible to minimize rounding or thickness non-uniformity of the high-viscosity slurry generated during the process, thereby providing a photocurable 3D printing method with improved precision.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those of ordinary skill in the art from the following description. will be.

1 is a flow chart of a photocurable 3D printing method using a high viscosity slurry according to an embodiment of the present invention.
2A to 2E are views for explaining each step of the photocurable 3D printing method using the high viscosity slurry of FIG. 1.
3A to 3C are partially enlarged views of portion R of FIG. 2D for explaining a process of solving the problem of thickness non-uniformity in the photocurable 3D printing method using a high viscosity slurry according to an embodiment of the present invention.
4A to 4C are diagrams for explaining a process in which a thickness non-uniformity problem occurs in a photocurable 3D printing method using a high viscosity slurry according to a comparative example.
5 is a perspective view showing an example of a partition wall in a photocuring 3D printing method using a high viscosity slurry according to an embodiment of the present invention.
6 is a perspective view showing another example of a partition wall in a photocuring 3D printing method using a high viscosity slurry according to an embodiment of the present invention.
7A and 7B are perspective and cross-sectional views illustrating structures output by a photocuring 3D printing method using a high viscosity slurry according to another embodiment of the present invention.
8 is a view for explaining a photo-curing 3D printing method using a high viscosity slurry according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part is said to be "connected" with another part, this includes not only "directly connected" but also "indirectly connected" with another element interposed therebetween. . In addition, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a flow chart of a photo-curing 3D printing method using a high viscosity slurry according to an embodiment of the present invention.

2A to 2E are views for explaining each step of the photocurable 3D printing method using the high viscosity slurry of FIG. 1.

The photo-curing 3D printing method using a high viscosity slurry according to an embodiment of the present invention can output a structure with excellent precision using a high viscosity raw material. Here, "high viscosity" means 5000cp or more. Preferably it may mean 5000cp to 100,000cp. The photocurable 3D printing method using a high viscosity slurry according to an embodiment of the present invention may perform photocurable 3D printing with excellent precision using the above-described high viscosity raw material.

Referring to FIG. 1, in the photocurable 3D printing method using a high viscosity slurry according to an embodiment of the present invention, a photocurable 3D printing slurry including a pigment and a photocurable resin is provided to a stage (S10).

Referring to Figure 2a, the photocurable 3D printing slurry 130 includes a pigment and a photocurable resin. Here, the pigment is a main material constituting the material of the product to be finally molded, and may be composed of ceramic or metal particles.

For example, ceramic pigments include aluminum oxide (Al ₂ O ₃ ), zirconia (ZrO ₂ ), titanium oxide (TiO ₂ ), silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), aluminum nitride (AlN), It may contain at least one of silica (SiO ₂ ), zinc oxide (ZnO), zinc sulfide (ZnS), and barium sulfide (BaS).

For example, as a metal pigment, at least one of aluminum (Al), tungsten carbide (WC), titanium (Ti), sus (SUS), iron (Fe), copper (Cu), nickel (Ni), and cobalt (Co) It can contain either.

Photocurable resin is a polymer resin containing photocurable organic functional groups, for example, polyester acrylate, epoxy acrylate, urethane acrylate, polyether acrylate, polyacrylate, silicone acrylate, unsaturated polyester, It may be a polymer resin containing at least one selected from epoxy.

The photocurable 3D printing slurry 130 includes a pigment in a content ratio of 70 to 90wt%, and a photocurable resin in a content ratio of 10 to 30wt%. As the content of the pigment is provided in an amount of 70 wt% or more, when the photo-curing 3D printing slurry 130 is photo-cured, the pigment may be uniformly and densely positioned on the polymer matrix, and the polymer matrix may be destroyed through the degreasing process. In this case, a structure composed of pure pigments can be finally formed.

In some embodiments, the pigment may be surface treated. For example, the surface of the pigment may be treated through a silane coupling agent including a vinyl group, an epoxy group, an amino group, a methacryloxy group, and a thiol group. In this case, the surface-treated pigment improves miscibility with the photocurable resin, and can maintain a uniformly dispersed state in the slurry. Evenly dispersed pigments can be strongly bonded to the polymer matrix of the photocurable resin upon photocuring. Accordingly, the pigments may be uniformly distributed in the molded structure, and even if the polymer matrix is removed by the degreasing process, the precision of the structure may be maintained.

Referring to FIG. 2B, the slurry 130 for photocuring 3D printing may be provided in the form of a layer on the stage 110 by using a blade 120 crossing the stage 110.

The stage 110 provides a space in which a structure is formed, and is configured in the form of a plate capable of supporting the structure. The stage 110 may have an area that is larger than or equal to the area of the bottom surface of the structure that is finally output. The stage 110 may have various shapes such as a circle, an oval, and a polygon.

The light irradiation unit 140 is disposed on the stage 110. The light irradiation unit 140 is configured to irradiate light onto the stage 110 to cure the slurry 130 for photocuring 3D printing on the stage 110. The light irradiation unit 140 may irradiate light of infrared rays, ultraviolet rays, or visible rays.

The light irradiation unit 140 may be composed of a laser or a beam projector that irradiates light only to a specific area. At this time, since the photocurable 3D printing slurry 130 is cured only in a specific area irradiated with light, a cured layer may be formed in a specific area irradiated with light.

When the light irradiation unit 140 is composed of a laser, light is concentrated at a specific point, and the light irradiation unit 140 may partially cure the photocurable 3D printing slurry 130 by moving the light irradiation point. In addition, when the light irradiation unit 140 is configured as a beam projector, light may be irradiated in a plane unit. In this case, the photocuring reaction occurs simultaneously and multiple times, and the structure can be rapidly formed on the stage 110.

The blade 120 provides the slurry 130 for photocuring 3D printing on the stage 110 in the form of a layer. The blade 120 is spaced apart from the upper surface of the stage 110 by a predetermined distance and moves from one side of the stage 110 to the other side of the stage 110, while forming the slurry 130 for photocuring 3D printing on the stage 110. Apply. The blade 120 has a length greater than or equal to the width of the stage 110 so that the photocurable 3D printing slurry 130 can be uniformly applied to the front of the stage 110, and the structure output on the stage 110 It can be made of a material having an appropriate elastic force so as not to damage the.

The blade 120 may be moved horizontally on the stage 110 in a direction crossing the stage 110. For example, the blade 120 may horizontally move in a direction crossing the stage 110 from one side of the stage 110 to the other side in a piston manner. However, the present invention is not limited thereto, and the blade 120 may be configured to move on a rail and may be moved horizontally.

The blade 120 may be configured to be able to move up and down from the upper surface of the stage 110. For example, the blade 120 may be raised to be spaced apart from the top surface of the stage 110 by 20 μm to 50 μm. In this case, while the blade 120 moves horizontally in a direction crossing the top surface of the stage 110, a layer of photocurable 3D printing slurry 130 having a thickness of 20 μm to 50 μm may be provided on the stage 110. have. However, the elevation height of the blade 120 is not limited thereto, and the elevation height of the blade 120 may be freely selected according to the thickness of the layer of the photocurable 3D printing slurry 130 to be provided.

Referring back to FIG. 1, the photo-curing 3D printing method using a high-viscosity slurry according to an embodiment of the present invention irradiates light to the photo-curing 3D printing slurry, so that one section of the structure and the partition wall spaced apart from the one section of the structure are One cross-section is formed (S20).

Referring to FIG. 2C, after the slurry 130 for photocuring 3D printing is provided in the form of a layer on the stage 110 by the blade 120, light is irradiated by the light irradiation unit 140.

As mentioned above, the light irradiation unit 140 irradiates light having energy to cure the photo-curing 3D printing slurry 130 from top to bottom. In this case, the light may be irradiated to only a part of the photo-curable 3D printing slurry 130. Specifically, light may be irradiated to a region corresponding to one end surface 151 of the structure to be finally formed. When light is irradiated, a photopolymerization reaction of the photocurable resin of the photocurable 3D printing slurry 130 is induced in the light irradiated region, and a polymer matrix is formed to form one end face 151 of the structure.

In addition, the light irradiation unit 140 may irradiate light to an area corresponding to one end face 161a and 161b of the partition wall spaced apart from one end face 151 of the structure. Through this, one end face 151 of the structure and one end face 161a and 161b of the partition wall spaced apart from each other are formed. For example, one end face 161a of the rear end bulkhead is formed behind one end face 151 of the structure based on the moving direction of the blade 120, and one end face of the structure based on the moving direction of the blade 120 One end surface 161b of the shear partition wall may be formed in front of the 151.

One end face 151 of the structure and one end face 161a and 161b of the partition wall may be spaced apart by a predetermined distance d. For example, one end face 161a of the rear end bulkhead may be spaced apart by 0.01 to 10 mm from the outline of one end face 151 of the structure adjacent thereto, and one end face 161b of the front end bulkhead is one of the adjacent structures. It may be spaced apart by 0.01 to 10 mm from the outline of the cross section 151. If one end face (161a, 161b) of the partition wall is separated by a distance (d) of less than 0.01mm from one end face 151 of the structure, the partition wall and the structure may be connected to each other during the photocuring process, and the partition wall from the structure It can be difficult to separate. In addition, when one end face 161a and 161b of the partition wall is spaced apart by more than 10 mm from the one end face 151 of the structure, the advantage of minimizing a rounding phenomenon due to the partition wall may be reduced. A detailed description of this will be described later with reference to FIGS. 3A to 4C.

Referring back to FIG. 1, the steps of providing a slurry and irradiating light are repeated until the structure is finally formed (S30).

Referring to FIG. 2D, after molding of one end face 151 of the structure and one end face 161a, 161b of the partition wall is completed, a view to cover one end face 151 of the structure and one end face 161a, 161b of the partition wall The slurry 130 for Hwa 3D printing is provided in the form of a layer.

Specifically, the blade 120 may be raised by a height corresponding to the height of a layer to be additionally provided based on the upper surface of the layer of the photocurable 3D printing slurry 130, which was initially provided. For example, the blade 120 may be raised by a height equal to the height of the layer of the initially provided photocurable 3D printing slurry 130 based on the upper surface of the layer of the photocurable 3D printing slurry 130 initially provided. have.

Thereafter, an additional photo-curable 3D printing slurry 130 is provided to one side of the stage 110, and the blade 120 horizontally moves in a direction crossing the stage 110, so that the photo-curable 3D printing slurry 130 An additional layer of may be provided.

An additional layer of the photocurable 3D printing slurry 130 may be provided to uniformly cover the upper surface of one end surface 151 of the structure. That is, the additional layer of the photocurable 3D printing slurry 130 formed on the one end surface 151 of the structure has a uniform thickness and has a substantially flat top surface.

On the other hand, as shown in the R region, the top surface of the additional layer of the photocurable 3D printing slurry 130 may be rounded in a region adjacent to one end face 161a and 161b of the partition wall. Specifically, based on the moving direction of the blade 120, the additional layer of the photo-curing 3D printing slurry 130 is formed at the rear edge of one end face 161a of the rear end bulkhead formed behind one end face 151 of the structure. The top surface can be rounded. In some embodiments, the addition of the photocurable 3D printing slurry 130 at the front edge portion of the one end face 161b of the shear bulkhead formed in front of the one end face 151 of the structure based on the moving direction of the blade 120 The top surface of the layer can be rounded. The rounding of the additional layer of the photocurable 3D printing slurry 130 includes the surface tension between the blade 120 and the photocurable 3D printing slurry 130 and the upper surface of the photocurable 3D printing slurry 130 and the stage 110 or It may be generated by a frictional force between the photo-curing 3D printing slurry 130 and one end faces 161a and 161b of the partition wall, and details thereof will be described later with reference to FIGS. 3A to 4C.

Referring to FIG. 2E, after an additional layer of the photocurable 3D printing slurry 130 is provided, light is irradiated, and the photocurable resin in the light irradiated region is cured to form another cross section 152 of the structure, and the partition wall The other cross-sections (162a, 162b) are formed.

After that, an additional layer of the photo-curing 3D printing slurry 130 is provided to cover the sections 151 and 152 of the cured structure and the sections 161a, 161b, 162a, 162b of the partition wall, and the structure Additional cross-sections and cross-sections of the partition wall may be formed. The above-described processes may be repeated until the structure is finally formed, and cross-sections of the structures are sequentially formed, thereby forming a three-dimensional structure.

The photocurable 3D printing method using a high viscosity slurry according to an embodiment of the present invention includes a light irradiation step (S20) of forming one end face 151 of the structure and one end face 161a, 161b of the partition wall spaced apart from the one end face 151 of the structure. Accordingly, a photocurable 3D printing slurry 130 having a uniform thickness may be provided on one end surface 151 of the structure, and a photocurable 3D printing slurry having a substantially flat top surface ( 130) may be continuously provided. Accordingly, cross-sections having a uniform thickness may be output, and output precision of photocurable 3D printing may be improved. Refer to FIGS. 3A to 4C for a detailed description of this.

3A to 3C are partially enlarged views of portion R of FIG. 2D for explaining a process of solving the problem of thickness non-uniformity in the photocurable 3D printing method using a high viscosity slurry according to an embodiment of the present invention.

4A to 4C are diagrams for explaining a process in which a thickness non-uniformity problem occurs in a photocurable 3D printing method using a high viscosity slurry according to a comparative example.

Referring to FIG. 3A, in a process in which the blade 120 provides a layer of the photo-cured 3D printing slurry 130, the blade 120 may pass over the top of one end surface 151 of the cured structure (ie, section A).

In this case, a surface tension may act between the slurry 130 for photo-curing 3D printing and the blade 120. In FIGS. 3A to 4C, the surface tension between the slurry 130 for photo-curing 3D printing and the blade 120 is shown by a dotted arrow. As the blade 120 is moved, the slurry 130 for photocuring 3D printing may flow together.

On the other hand, another surface tension acts between the one end surface 151 of the cured structure and the photo-cured 3D printing slurry 130. In this case, the surface tension between the one end surface 151 of the cured structure and the photocurable 3D printing slurry 130 hinders the flow of the photocurable 3D printing slurry 130 flowing as the blade 120 moves. It acts in the direction to which it works, and acts as a frictional force. The frictional force acting on the photocurable 3D printing slurry 130 flowing in FIGS. 3A to 4C is shown by a solid arrow.

When the frictional force between one end face 151 of the cured structure and the photocurable 3D printing slurry 130 is sufficiently strong, the photocurable 3D printing slurry 130 is cured despite the movement of the blade 120 It remains on one end face 151 of, and accordingly, a layer of the photocurable 3D printing slurry 130 is provided.

When the blade 120 passes one end face 151 of the structure and passes one end face 161a of the partition wall formed around the one end face 151 of the structure, photo-curing 3D printing slurry that flows along the blade 120 130 is continuously receiving the frictional force due to one end face 161a of the partition wall, and even if the blade 120 passes one end face 151 of the structure and passes one end face 161a of the partition wall, one end face 151 of the structure ) And a layer of the photocurable 3D printing slurry 130 having a uniform thickness may be provided on one end surface 161a of the partition wall.

Referring to FIG. 3B, when the blade 120 passes the corner of one end face 161a of the partition wall and passes the section B, it is generated between the upper surface of the one end face 161a of the partition wall and the slurry 130 for photocuring 3D printing. The resulting frictional force disappears, and a frictional force is generated between the upper surface of the stage 110 and the photocurable 3D printing slurry 130. In this case, since the frictional force action point in the B section is farther away than the friction force action point in the A section, the photocurable 3D printing slurry 130 flowing in accordance with the movement of the blade 120 flows more easily. That is, since the frictional force by the stage 110 is largely applied to the photocurable 3D printing slurry 130 that flows close to the stage 110, the flow is suppressed. On the other hand, the slurry 130 for photocuring 3D printing on the surface spaced apart from the stage 110 may facilitate flow since the surface tension of the blade 120 is greater than the frictional force of the stage 110. Accordingly, the flow of the photo-curing 3D printing slurry 130 along the blade 120 at the edge of one end face 161a of the partition wall increases, and as a result, photo-curing 3D printing is performed at the edge of one end face 161a of the partition wall. The upper surface of the slurry 130 is bent and rounding occurs.

In other words, while the blade 120 passes through section A, the frictional force between one end surface 151 of the structure and the photocurable 3D printing slurry 130 and the surface tension between the blade 120 and the photocurable 3D printing slurry 130 Since this is sufficiently close, the flow of the photocurable 3D printing slurry 130 according to the movement of the blade 120 is difficult, but one end face (161a) of the partition wall and the photocurable 3D printing slurry while the blade 120 enters section B Since the frictional force between 130 disappears, and frictional force between the stage 110 and the photocurable 3D printing slurry 130 is generated, the distance between the surface tension and the frictional force increases and the photocuring 3D according to the movement of the blade 120 The flow of the printing slurry 130 may be facilitated.

Referring to FIG. 3C, as the blade 120 moves away from the edge of one end face 161a of the partition wall, the photo-curing 3D printing slurry 130 continuously flows along the blade 120, and thus one end face of the partition wall (161a) The thickness of the layer of the photocurable 3D printing slurry 130 may be reduced in section B based on the corner. .

On the other hand, rounding of the photocurable 3D printing slurry 130 generated at the edge of one end surface 161a of the partition wall does not affect the layer thickness of the photocurable 3D printing slurry 130 provided on one end surface 151 of the structure. Does not. That is, as shown in FIGS. 3B and 3C, the rounding of the photocurable 3D printing slurry 130 occurs only around the edge of one end face 161a of the partition wall, and does not occur at the edge of one end face 151 of the structure. Does not. That is, one end face 161a of the partition wall and one end face 151 of the structure are separated by a short distance within 10 mm, and the friction force caused by one end face 151 of the structure in the process of passing the blade 120 is one end face of the partition wall It is connected and operated by frictional force by (161a). Accordingly, rounding of the photocurable 3D printing slurry 130 may not occur at the corner of one end face 151 of the structure, and a photocurable 3D printing slurry having substantially the same thickness on one end surface 151 of the structure A layer of 130 may be provided.

On the other hand, as shown in FIGS. 4A to 4C, when one cross-section of the partition wall does not exist in the periphery of one cross-section 451 of the structure, the photo-curing 3D printing of a uniform thickness is used on one cross-section 451 of the structure. The layer of the slurry 430 may not be provided.

Specifically, as shown in FIG. 4A, when the blade 420 passes through section A, the frictional force acting on the photo-curing 3D printing slurry 430 flowing along the blade 420 is one end surface 451 of the structure. Because it acts on the phase, the amount of the photocurable 3D printing slurry 430 flowing along the blade 420 is constant, and a layer of the photocurable 3D printing slurry 430 having a uniform thickness on one end surface 451 of the structure is Is provided.

However, as shown in FIG. 4B, when the blade 420 passes through the edge of one end face 451 of the structure and moves to section B, the slurry 430 for photocuring 3D printing flowing along the blade 420 The acting frictional force is generated on the upper surface of the stage 410. Accordingly, rounding of the photocurable 3D printing slurry 430 occurs at the edge of one end face 451 of the structure, and the thickness of the photocurable 3D printing slurry 430 at the edge of one end face 451 of the structure decreases. I can.

As shown in FIG. 4C, as the blade 420 continuously moves in section B, the flow of the photo-curing 3D printing slurry 430 continues along the blade 420, and one end face 451 of the structure The layer thickness of the photo-curing 3D printing slurry 430 in section B may be thinned based on.

As the thickness of the photo-curing 3D printing slurry 430 at the edge of one end face 451 of the structure decreases, the molding accuracy of the other end face of the structure to be formed on one end face 451 of the structure may decrease. That is, the variation in the thickness of the layer of the photocurable 3D printing slurry 430 is expressed as a variation in the thickness of the other section of the structure to be molded on the one section 451 of the structure, and causes a problem of reducing the molding precision of the structure.

That is, since the layer of the photocurable 3D printing slurry 430 rounded at the edge of one end face 451 of the structure is continuously accumulated and provided, sections with reduced edge thickness are provided on one end face 451 of the structure. It is continuously stacked, and this may reduce the accuracy of the output to the corners of the structure.

In addition, the above-described rounding phenomenon may be largely generated at the rear and side edges of the one end surface 451 of the structure based on the moving direction of the blade 430. That is, in the front part of one end surface 451 of the structure on the movement path of the blade 430, the photocuring 3D printing slurry 430 flowing along the blade 430 receives frictional force by the one end surface 451 of the structure. Therefore, the flow can be suppressed. On the other hand, in the rear and side corners of one end face 451 of the structure, the friction force caused by the one end face 451 of the structure suddenly disappears, so the flow of the photo-curing 3D printing slurry 430 according to the movement of the blade 430 This can be facilitated, and rounding can occur significantly.

3A to 3C, the photo-curing 3D printing method using a high viscosity slurry according to an embodiment of the present invention forms one end surface 161a of the partition wall around one end surface 151 of the structure, so that the high viscosity slurry Even if is used, a rounding phenomenon at the corner of one end surface 151 of the structure can be minimized. That is, even if the blade 120 is moved from the edge of one end face 151 of the structure, the flow of the photocurable 3D printing slurry 130 is suppressed due to the frictional force of one end face 161a of the partition wall, A layer of the slurry 130 for photocuring 3D printing having a uniform thickness may be provided on the front surface of the 151.

In particular, since one end face 161a of the rear end bulkhead is formed behind one end face 151 of the structure based on the moving direction of the blade 120, rounding that may occur at the rear edge of one end face 151 of the structure is effectively Can be suppressed. In addition, by forming one end face 161b of the shear bulkhead in front of one end face 151 of the structure, even if the blade 120 is driven in the reverse direction to provide the slurry 130 for photocuring 3D printing, one end face of the structure ( Rounding that may occur at the front edge of 151) can be effectively suppressed.

As the photocurable 3D printing slurry 130 is provided at a uniform thickness on one end surface 151 of the structure, the other end surface 152 of the structure formed on one end surface 151 of the structure is formed to have a uniform thickness. In addition, since the cross-sections of the structure can be continuously formed to have a uniform thickness, the molding precision of the structure can be improved.

5 is a perspective view showing an example of a partition wall in a photocuring 3D printing method using a high viscosity slurry according to an embodiment of the present invention.

Referring to FIG. 5, a partition wall 560 that suppresses rounding due to blade movement may be configured to surround the structure 550. As described above, the rounding phenomenon of the slurry for photocuring 3D printing according to the movement of the blades often occurs at the edge of the cross-section of the structure. In particular, the rounding phenomenon is generated by focusing on the rear and side edges of the structure 550 on the movement path of the blade. However, in some cases, the photocurable 3D printing slurry may flow non-uniformly at the front edge of the structure 550 to cause a rounding phenomenon. For example, in a photocurable 3D printer in which the blade is driven in both directions to provide a photocurable 3D printing slurry, a rounding phenomenon may occur at all corners of the structure 550.

As shown in FIG. 5, when the partition wall 560 is configured in an enveloping type, since all corners of the structure 550 are surrounded by the partition wall 560, rounding generated in the process of forming the cross section of the structure 550 This can be suppressed by the partition wall 560, the output precision of the structure 550 can be further improved.

6 is a perspective view showing another example of a partition wall in a photocuring 3D printing method using a high viscosity slurry according to an embodiment of the present invention.

Referring to FIG. 6, the partition walls 660a and 660b may be formed to surround all outer surfaces of the structure 650. In this case, the partition walls 660a and 660b may be composed of a plurality of separated pieces. For example, as shown in FIG. 6, when the structure 650 has a cylindrical shape, the partition walls 660a and 660b include a first partition wall 660a and a structure 650 surrounding the left outer surface of the structure 650. ) May be composed of a second partition wall (660b) surrounding the right outer surface.

When the partition walls 660a and 660b are composed of a plurality of separated pieces, the structure 650 and the partition walls 660a and 660b may be easily separated. As described above, the partition walls 660a and 660b are configured to suppress the rounding of the photo-cured 3D printing slurry by the blade, and thus are spaced apart from the structure 650 by a distance within 10 mm of one end face of the structure 650. That is, the structure 650 and the partition walls 660a and 660b are separated at very fine intervals, and damage may be inflicted on the structure 650 due to the operator's carelessness in the process of separating the structure 650 from the partition walls 660a and 660b. I can. In particular, when the partition walls 660a and 660b are configured as one body, it may be very difficult to separate the structure 650 from the partition walls 660a and 660b. In particular, the uncured photo-cured 3D printing slurry may remain on the partition walls 660a and 660b and the structure 650, and may interfere with the separation of the partition walls 660a and 660b from the structure 650. However, when the partition walls 660a and 660b are composed of a plurality of pieces, the structure 650 and the partition walls 660a and 660b are easily separated by separating the first partition wall 660a and the second partition wall 660b. ) Has the advantage of being able to separate it.

Meanwhile, a supporter 670 connecting the structure 650 and the stage may be formed during the photocuring 3D printing process. Specifically, in the process of forming cross-sections of the structure 650 by irradiating light to the photo-curable 3D printing slurry, a supporter 670 may be formed to connect one end surface of the structure and the stage.

The supporter 670 is a structure formed to support a portion of the upper section that is not supported by the lower section when the area of the upper section is larger than the area of the lower section of the structure 650. As shown in FIG. 6, in the case of the cylindrical structure, the area of the lower cross sections is smaller than the area of the upper cross sections based on the central axis of the cylinder. In this case, a part of the upper end surface cannot be supported by the lower end surface, and may be formed in a state floating in the air. In this case, there may be a problem that the upper end surface is hit by gravity while the upper end surface is hardened. However, when the supporter 670 is formed, since the upper end surface that is not supported by the lower end surface is supported by the supporter 670, the problem of hitting the upper end surface by gravity can be minimized.

Meanwhile, when the partition walls 660a and 660b are formed to surround the outer shape of the structure 650, the number of supporters 670 may be minimized. That is, in the process of forming the cross-sections of the structure 650, cross-sections of the partition walls 660a and 660b may be formed around the edges of the upper cross-section that are not supported by the lower cross-section, and are used for photocuring 3D printing of uncured high viscosity The upper cross-sectional edge may be connected to cross-sections of the partition walls 660a and 660b by the slurry. Accordingly, the sagging phenomenon of the edge of the upper section may be suppressed, and some supporters 670 for suppressing the sagging of the upper section may be omitted.

As some of the supporters 670 are omitted, a problem of damage to the structure 650 occurring in the process of separating the supporter 670 into the structure 650 may be minimized. The supporter 670 is a configuration that suppresses the gravitational sagging of the cross sections in the process of forming the structure 670, and thus must be removed from the final structure 650. However, since the supporter 670 is formed in a state in contact with the structure 650, a stress is applied to the structure 650 in the process of cutting the supporter 670 at the structure 650, and May cause cracking. However, as the partition walls 660a and 660b are formed, the gravitational sagging of the upper section that is not supported by the lower section can be suppressed, so that the number of formations of the supporters 670 can be minimized, so that the supporters 670 are removed. Micro-cracks generated in the process may be minimized, and the molding precision of the structure 650 may be further improved.

7A and 7B are perspective and cross-sectional views illustrating structures output by a photocuring 3D printing method using a high viscosity slurry according to another embodiment of the present invention.

The photo-curing 3D printing method using a high-viscosity slurry according to embodiments of the present invention may be applicable to molding a complex structure. Specifically, as shown in FIGS. 7A and 7B, it can be easily applied to the output of the structure 750 having a concave cavity (CV).

Referring to Figures 7a and 7b, the photocurable 3D printing method using a high viscosity slurry according to another embodiment of the present invention can be applied to the output of a structure 750 used as an implant prosthesis having a cavity (CV). The implant prosthesis has a cavity (CV) having an inner surface corresponding to the outer shape of the abutment so that it can be mounted on the implant abutment, and the outer surface of the cavity (CV) has a tooth shape.

By forming a partition wall to be spaced apart from the outer surface of the cavity CV, rounding of the photocurable 3D printing slurry generated at the outer edge of the cavity CV may be suppressed. However, as described above, since the inner surface of the cavity CV must be molded to correspond to the outer shape of the abutment, a partition wall cannot be formed in the inner region of the cavity CV, and is generated at the inner edge of the cavity CV. It may not be possible to suppress the rounding of the photocurable 3D printing slurry.

In the photocurable 3D printing method using a high viscosity slurry according to another embodiment of the present invention, the structure 750 may be output in an inclined state so that the rounding phenomenon can be minimized during the molding process of the structure having the cavity (CV).

8 is a view for explaining a photo-curing 3D printing method using a high viscosity slurry according to another embodiment of the present invention.

Referring to FIG. 8, in the photocurable 3D printing method using a high viscosity slurry according to another embodiment of the present invention, in the light irradiation step, the structure 750 is output in an inclined state with respect to the stage 110. The printing slurry 130 is irradiated with light to form one end face of the inclined structure 750 and one end face of the partition wall 760 spaced apart from the one end face of the structure 750.

As described above, the rounding of the photocurable 3D printing slurry 130 may occur at the rear edge of one end face of the structure 750 based on the moving direction of the blade 120. In the case of the structure 750 including the cavity (CV), the inner shape of the structure 750 exists beyond the rear edge of the cavity (CV) based on the moving direction of the blade 120, so that the partition wall 760 can be formed. Can't.

According to another embodiment of the present invention, when the rear side of the cavity CV is disposed substantially parallel to the upper surface of the stage 110 based on the moving direction of the blade 120, the cavity with respect to the upper surface of the stage 110 The slope of the rear side of the (CV) may be smooth, and rounding on the rear side of the cavity (CV) may be alleviated.

Specifically, when the structure 750 is output without being inclined with respect to the stage 110, the side surface of the cavity CV may have a steep inclination with respect to the stage 110. As described above, the rounding of the photocurable 3D printing slurry 130 causes the action point of the frictional force acting on the photocurable 3D printing slurry 130 flowing due to the movement of the blade 120 to move away from the blade 120 It is caused by. When the side slope of the cavity (CV) is steep, the point of action of the frictional force acting on the photocurable 3D printing slurry 130 flowing along the blade 120 in the process of forming the cross-sections of the side surfaces of the cavity (CV) suddenly It can be away from the blade 120. Accordingly, a lot of rounding of the photo-curable 3D printing slurry 130 may occur at the rear side of the cavity CV.

On the other hand, when the structure 750 is output while inclined with respect to the stage 110, the side surface of the cavity CV may have a gentle (or substantially flat) inclination with respect to the stage 110. In this case, the photocurable 3D printing slurry 130 flowing along the blade 120 continuously receives the frictional force of the rear sides of the cavity CV having a gentle slope, and rounding can be minimized.

In this case, the slope (a) of the structure 750 with respect to the stage 110 may be freely selected in the range of 0° to 90°. Preferably, the slope (a) may be determined so that the rear side of the cavity CV of the structure 750 is positioned substantially parallel to the top surface of the stage 110. However, as the structure 750 is tilted, the number of cross-sections to be output may increase, and the output time may increase. Accordingly, the slope (a) of the structure 750 with respect to the stage 110 may be determined in an appropriate way to minimize the output time while minimizing rounding at the rear side edge of the cavity CV.

As described above, in the photocurable 3D printing method using a viscosity slurry according to another embodiment of the present invention, the cross sections of the structure and the cross sections of the partition wall are formed so that the structure 750 is output in an inclined manner based on the stage 110. do. Through this, the inclination of the rear side of the cavity CV may be smooth, and a change in friction force with respect to the photo-curing 3D printing slurry 130 flowing along the blade 120 may be made smoothly. That is, a continuous friction force acts by the rear side of the cavity CV, and rounding of the photo-curing 3D printing slurry 130 generated by instantaneously reducing the friction force can be minimized.

The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. do.

110, 410: stage 120, 420: blade
130, 430: photo-curing 3D printing slurry 140: light irradiation unit
151, 451: one section of the structure
161a, 161b, 162a, 162b: one cross section of the bulkhead
550, 650, 750: structures
560, 660a, 660b, 760: bulkhead
670: supporter CV: cavity

Claims (10)

A slurry providing step of providing a slurry for photocuring 3D printing including a pigment and a photocurable resin to a stage; And
Including a light irradiation step of irradiating light to the photocurable 3D printing slurry to form a cross-section of a structure and a cross-section of a partition wall spaced apart from the cross-section of the structure,
One section of the partition wall is spaced apart from the outline of one section of the structure by a set distance so that the friction force by one end surface of the structure acting on the photo-curing 3D printing slurry is connected to the friction force by the one end section of the partition wall. Photo-curing 3D printing method using a high viscosity slurry. The method of claim 1,
The step of providing the slurry,
Including the step of providing the photo-curable 3D printing slurry to the stage in a layer form using a blade crossing the stage,
The light irradiation step,
A photocurable 3D printing method using a high-viscosity slurry comprising the step of forming a cross-section of a rear end bulkhead at a rear of one cross-section of the structure based on the moving direction of the blade. The method of claim 2,
The light irradiation step,
The photo-curing 3D printing method using a high viscosity slurry further comprising the step of forming a cross-section of the shear bulkhead in front of the cross-section of the structure based on the moving direction of the blade. The method of claim 1,
The step of providing the slurry,
Including the step of providing the photocurable 3D printing slurry to the stage in the form of a layer using a blade crossing the stage,
The light irradiation step,
A photocurable 3D printing method using a high viscosity slurry comprising the step of forming an enclosing partition wall to surround one end surface of the structure. The method of claim 4,
The step of forming the enclosing partition wall to surround one end face of the structure,
Photo-curing 3D printing method using a high viscosity slurry comprising the step of forming the enclosing partition wall separated into a plurality of pieces. The method of claim 4,
One cross section of the structure is spaced apart from the upper surface of the stage,
The light irradiation step,
A photocurable 3D printing method using a high viscosity slurry further comprising the step of forming a supporter connecting one end face of the structure and the stage. The method of claim 1,
The structure includes a cavity recessed from the top,
The light irradiation step,
Forming a section of the inclined structure and a section of the partition wall spaced apart from the section of the structure by irradiating light to the photocurable 3D printing slurry so that the structure is output in an inclined state based on the stage Containing, photocurable 3D printing method using a high viscosity slurry. The method of claim 7,
The structure is output in a state that is inclined at an inclination within 90° with respect to the stage, a photocurable 3D printing method using a high viscosity slurry. The method of claim 1,
One cross-section of the partition wall is spaced 0.01 to 10 mm from the outline of the cross-section of the structure, photo-curing 3D printing method using a high viscosity slurry. The method of claim 1,
The photocurable 3D printing slurry has a viscosity of 5000cp or more, a photocurable 3D printing method using a high viscosity slurry.

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