JP2003340813A - Method of manufacturing ceramic molded body and equipment using the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the manufacture of a ceramic molded body which requires much time and labor and very troublesome work and brings about nonuniformity in the quality according to manufactures. <P>SOLUTION: The ceramic molded body being an object is obtained by making powder, a gel or the like discharged on the basis of set data of the data which are obtained from three-dimensional imagination of the structure of the ceramic molded body and are decomposable. By adding primary colors to the powder and by injecting it in a plurality of shots, an object of dental prosthesis colored in a desired way is obtained. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to the manufacture of ceramics.

[0002]

2. Description of the Related Art A ceramic molded body is manufactured by pouring mud into a mold such as slip casting and drying it, or by injection molding, using a ceramic powder containing a binder as a mold. There are methods of forming by spraying, pressure molding, plastic molding, etc., but since these are molded according to the shape of the mold,
Although the appearance is somewhat complicated, if it is inside the molded body and is cut off from the outside, it is complicated to combine and combine partially formed products. Required work. On the other hand, as for the use of CAD / CAM, a method of forming a virtual three-dimensional structure on a computer and grinding the block based on this is also proposed. Cannot escape the complicated work described above.

[0003]

Many of the ceramics are used as biomaterials in medicine and dentistry, and are used as stable and safe materials as compared with metals and resins. However, the production of a conventional ceramic molded body is very time-consuming and requires a very complicated work. In addition, manufacturing of ceramics used as a dental prosthesis is performed manually by a dental technician, and quality and accuracy vary depending on a person. Further, what is needed for the ceramic molded body is not limited to the fields of medical science and dentistry, and there are many.

[0004]

The present invention has as its object 3
A step of three-dimensional shape measurement for referring to a certain shape in order to create a three-dimensional virtual structure. If you need to color, image analysis steps for reference. Based on the above measurement data, create a three-dimensional virtual structure by CAD etc.
Virtual structure manufacturing step to convert into processing data such as AM. While discharging ceramic powder or gel,
The step of producing a molded body. A method for freely producing a ceramic molded body, which includes a step of firing the molded body, is realized. Above all, the present invention is suitable for manufacturing a dental prosthesis which requires various shaping. Ceramics in the present invention, hydroxyapatite, calcium phosphate compounds such as alpha calcium phosphate, beta calcium phosphate, porcelain such as feldspar, quartz, silica stone,
Examples include various materials such as alumina, zirconia, titanium oxide, and metal oxides of magnesium oxide. The ceramic gel in the present invention is, for example, based on 1 of the above-mentioned ceramic powder (particle diameter 0.1 μm to 100 μm),
A mixture of 0.1 to 3 times the amount of water is shown, and if necessary, cornstarch, starch, polyvinyl alcohol, etc. are added as a binder in an amount of 0.01 to 1 times the amount of the ceramic powder. The amount of the binder is appropriately determined depending on the type of ceramics and the like. As the porcelain powder, a powder (frit) that is once dissolved, solidified, and pulverized may be used in some cases. Impurities can be eliminated by fritting. The ceramic gel preferably has a degree of drying and solidifying during the molding operation, and the drying and solidifying speed can be adjusted according to the molding speed, and if the solidifying speed is slow, the injection molding speed is lowered. The adjustment can be made appropriately.
Further, in some cases, there is also a method in which the ceramic gel is concentrated and the water content floats by applying vibration to the built up material, and the solidification is promoted by removing the water content. As a method of shaping with ceramic powder, a binder is applied to a certain mold in advance, and then the ceramic powder is applied. When the thickness is required, it can be solved by alternately coating the binder and the ceramic powder. In addition, the present invention also includes the case of spraying a colorant instead of the gel to color the prosthesis. That is, since the color of the dental prosthesis manufactured is not necessarily the same as the color of the adjacent tooth, the difference in tooth color is noticeable especially in the front tooth. Therefore, in order to eliminate this difference, the present invention provides, for example, a CCD camera and a CD.
S, a light-receiving element (for example, a combination of three light-receiving elements having an RGB filter), a scanner or the like is used to measure the coloring of adjacent teeth, and then the coloring agent is electromechanically selected and determined based on the coloring data. It is possible to form a state in which the prosthesis and the natural tooth are indistinguishable by discharging and coloring the selected and determined coloring agent on the prosthesis. or,
In some cases, coloring may be performed together with the ejection molding of the ceramic gel or the ceramic powder. The three-dimensional shape measurement step of the present invention refers to a reference three-dimensional virtual structure using a contact-type probe or a device capable of measuring three-dimensional shape such as optical measurement using laser light. It measures the dimensional shape. Moreover, if a three-dimensional virtual structure can be produced only by a computer,
It does not necessarily require this step. In the image analysis step, if there is something to refer to when coloring a ceramic molded body, the image is taken into a computer with a digital camera, digital video camera, scanner, etc., and the three primary colors of light are R (red) G (green). ) A step of analyzing the color of each portion by a generally used method such as a method of decomposing into B (blue) and analyzing the color, and this step is not necessarily required. In the virtual structure manufacturing step, if a reference shape or color exists, the data is taken into a computer, and the target shape is created on the computer by CAD or the like to create a virtual structure. Further, it is a step of converting the virtual structure into processed data by CAM or the like. Inject syringe, coloring agent, ceramic powder or gel.
Plural syringes are prepared depending on the type of coloring agent or ceramic. This is a step of moving the syringe based on the processed data of the virtual structure and producing a ceramic molded body by an apparatus having a three-dimensional drive unit for discharging a fixed amount. In the firing step, the ceramic molded body is heated to a temperature of 50.
It is fired at 0 to 2000 ° C. for 0.1 hour to 48 hours, and is appropriately selected depending on the properties of ceramics and molded products. Also, as the firing environment, vacuum, reduced pressure, high pressure, etc., atmosphere of nitrogen, argon, etc. are appropriately selected depending on the properties of the ceramics or the molded product. The mold used for discharging the ceramic powder or gel should have both the role of working model and the role of refractory material for firing porcelain.Basic composition is α-quartz and cristobalite, and it should be used as a binder. A refractory material using magnesia is conceivable. In the present invention, the base is, for example, a mold to be further molded, a mold to form a molded product, a mold to be molded around its periphery, and a mold to be removed later. The relative movement in the present invention refers to a case where the base is fixed and the discharge means is moved, and a case where the discharge means is fixed and the base is moved. The discharging operation refers to, for example, discharging the ceramic powder or gel continuously or intermittently while moving or while stopping the movement.

Example 1 The device (15) of the present invention automatically builds up a dental ceramic crown. This device (14)
Has an X-axis motor (3), a Y-axis motor (14) and a Z-axis motor (8) on the X-axis (12), Y-axis (13) and Z-axis (6), respectively, and moves three-dimensionally. Is made possible. Ceramics gel mainly composed of feldspar and composed of the following components Feldspar powder (average particle size 15 μm) 35% by weight Clay 15% by weight Polyvinyl alcohol 5% by weight Water 45% by weight are put in the dedicated tank (1). This ceramic gel is in a state in which color powder used in dentistry is mixed. Here, due to the difference in color of ceramics mainly composed of feldspar,
I prepared a variety of things. The six types are A2, A3, A3.5, A4, transparent, and stain in the dentistry. Six kinds of ceramic gels are supplied from the respective dedicated tanks (1) to the syringes (9) through the hoses (7) by the pumps (2). Each ceramic gel supplied to the syringe is discharged from the discharge port (10) to produce a ceramic molded body. 3 shows the production of a dental prosthesis crown. Take an impression of the dentition and make a refractory model (16) from the impression material. The refractory model material used here is one normally used in dentistry, and its basic composition is α-quartz and cristobalite, and magnesia is used as a binder. This plays both a role as a working model and a role as a refractory material for firing porcelain. The fire-resistant model (16) with the abutment teeth modeled is digitized with a three-dimensional shape measuring device. The adjacent teeth of the prosthetic crown are photographed with a digital camera, and the image data is analyzed on a personal computer for color. A virtual crown is created by CAD based on the digitized three-dimensional shape data and the analysis data of the color of the adjacent tooth. Virtual data on a personal computer is decomposed in the Z-axis direction and converted into processed data. An abutment model (16) made of refractory material in place on the device
(Fig. 2). The ceramic gel is ejected in a fault-like manner on the refractory abutment model. The ceramic molded body (18) produced as shown in FIG. 3 was fired together with the refractory model (16) in an electric furnace for dental technicians.
The fired ceramic compact was removed from the refractory model and completed.

Example 2 An impression of a connecting crown is taken and a working model (19) is made of plaster. This gypsum model (19) was measured in three-dimensional shape, and an alumina coping crown (20) was produced by grinding with a dental CAD / CAM. Create virtual data to build on alumina on a personal computer. In place on the device,
Install the alumina connecting coping crown (20) (FIG. 4). A ceramic gel is built up as in Example 1. The ceramic molded body (21) with an alumina coping as shown in FIG. 5 was fired in an electric furnace for dental technicians to complete the molding.

Example 3 A dental prosthesis obtained by a CAD / CAM apparatus for dental technique is a single color because it is processed from a block (cutting material). With this device it is also possible to color the crown obtained with a CAD / CAM device for dental technicians. By using the crown obtained by the CAD / CAM device for dental technique, the work of assembling can be omitted, so that the time can be shortened. A dental / technical CAD / CAM device (for example, the device described in Japanese Patent Laid-Open No. 10-58281) is used to mount the front tooth crown obtained by grinding on the device. The color of the crown is determined by analyzing the image of the adjacent tooth on a personal computer in advance. CA for dental technique
The three-dimensional shape data of the crown used in the D / CAM device was taken into this device and used as the data of the crown surface. Based on the surface shape data and the data for color arrangement, a colorant was applied to the crown by this device (15). afterwards,
Completed by firing in an electric furnace for dental technology.

[Brief description of drawings]

FIG. 1 is a diagram showing an apparatus for manufacturing a ceramic molded body by discharging a ceramic gel, which is an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of the present invention.

FIG. 3 is a diagram illustrating an example of the present invention.

FIG. 4 is a diagram illustrating an example of the present invention.

FIG. 5 is a diagram illustrating an embodiment of the present invention.

[Explanation of symbols]

1 Ceramics gel dedicated tank 2 Ceramics transport pump 3 X-axis motor 4 Abutment tooth dedicated stand 5 Ceramic molded body 6 Z axis 7 Ceramics transport hose 8 Z-axis motor 9 syringe 10 Ceramic discharge port 11 Dedicated base mounting jig for mounting abutment 12 X axis 13 Y axis 14 Y-axis motor 15 Ceramics molding equipment 16 Fireproof model 17 Abutment dedicated tooth mounting base 18 Ceramics molded body 19 plaster model 20 Alumina coping crown 21 Ceramic molded body

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Claims (7)

[Claims] 1. The structure of a desired ceramic molded body is
A manufacturing method for obtaining a target ceramics compact by discharging one or more of a powder, a gel, and a coloring agent based on aggregate data of decomposable data . 2. An apparatus for manufacturing a ceramic molded body having a discharge molding means for molding a ceramic powder or gel on a base by relative three-dimensional movement discharge based on model data obtained by converting a model shape into three-dimensional data. . 3. An apparatus for manufacturing a ceramic molded body having a coloring output means for outputting a colorant by three-dimensional relative movement on a prosthesis based on model coloring data obtained by converting a model shape into three-dimensional data. 4. The method for producing a ceramic molded body according to claim 1, which comprises a step of firing the molded body obtained above, or an apparatus using the same. 5. The method for producing a ceramic molded body according to claim 1, 2 or 3, or an apparatus using the same, having a plurality of discharges depending on the material and colorant of the ceramics. 6. The method for producing a ceramic molded body according to claim 1, wherein the powder or gel or the like is discharged onto a mold using a mold, or an apparatus using the same. 7. The method for producing a ceramic molded body according to claim 1, or an apparatus using the same, which is carried out by discharging the powder or gel onto a ceramic prepared in advance.