Glass-ceramic molded article and manufacturing method therefor

Abstract

The present invention relates to a glass-ceramic molded article and a manufacturing method therefor. The glass-ceramic molded article is manufactured by debinding and crystallization heat treatment of a 3D printed object including an organic binder and crystalline glass particles, to include a crystalline phase dispersed in a glass matrix, unlike the 3D printed object. Therefore, a high-strength glass-ceramic molded article can be provided with a low volume shrinkage rate using a simple method, and the high-strength glass-ceramic molded article may be useful, for example, as a glass-ceramic prosthesis.

Description

Glass ceramic molded body and method of manufacturing the same

[0001] The present invention relates to a glass ceramic molded body and a method for manufacturing the same, and more specifically, to a method for producing a high-strength glass ceramic molded body with a low shrinkage rate and a simplified process, and to a molded body obtained therefrom.

[0002] The concept of 3D printing and additive manufacturing was established by ASTM in 2009 by supplementing and expanding the existing concept of rapid prototyping, and it is defined as "a process technology that manufactures products layer by layer from 3D model data, in contrast to subtractive manufacturing, which involves removing material from the original material through processing."

[0003] Additive manufacturing processes have advantages in producing dental prosthetics such as inlays, crowns, or bridges, primarily because they can simplify the impression taking and casting processes, which require significant manual labor in dental laboratories in the case of ceramic materials, and also avoid material loss that occurs in non-productive processes such as milling and grinding.

[0004] The biggest difference between 3D printing using ceramic materials and the manufacturing of 3D molded bodies using polymers or metals is that, in most cases, post-processing including degreasing and densification through sintering is absolutely necessary after 3D molding. To maximize the advantages of 3D printing technology, it must be possible to control the volume shrinkage and deformation of the 3D structure caused by heat treatment throughout the entire process, from the selection of raw powder to sintering conditions.

[0005] For example, in a manufacturing method for ceramic molded parts using photopolymerization technology, a ceramic green compact is first produced through stacked radiation curing of free-flowing ceramic slip, and then sintered after debinding to form a high-density ceramic molded body. Here, the green compact is also referred to as a green body. The removal of the binder is called debinding. The binder used in this process is generally removed by heating the green compact to a temperature of approximately 80°C to 600°C, and it is important to prevent the occurrence of cracks and deformation as much as possible during this process. When the green compact is debinded, it becomes a so-called brown body. During the debinding process, the binder is decomposed into volatile components through thermal and thermochemical processes.

[0006] The sintering of the white body takes place during high-temperature firing in a sintering furnace. Therefore, the finely dispersed ceramic powder is exposed to a temperature lower than the melting temperature of the main component, where it is compressed and solidified; as a result, the porous components are reduced and the strength increases.

[0007] As an example of a manufacturing process for a ceramic prosthesis using an additive manufacturing process, U.S. Patent No. 10624820 describes a slip comprising at least one radical polymerizable monomer, at least one photoinitiator, ceramic and / or glass ceramic particles, and a nonionic surfactant, and also describes a method of curing such slip to produce a green compact, degreasing the green compact to obtain a white body, and then sintering the white body to produce a ceramic or glass ceramic molded body.

[0008] The present invention aims to provide a method for manufacturing a glass ceramic molded body that can obtain a glass ceramic molded body, which is a high-strength structure, from a 3D printed object with a low volume shrinkage rate.

[0009] The present invention also aims to manufacture a glass ceramic molded body having high strength obtained from a 3D printed mold.

[0010] The present invention aims to provide a 3D printed body that enables the production of a high-strength glass ceramic molded body in a simple manner.

[0011] One embodiment of the present invention provides a method for manufacturing a glass ceramic molded body, comprising the steps of: obtaining a 3D printed molded body comprising an organic binder and crystalline glass particles; degreasing to obtain a compact of crystalline glass particles from the 3D printed molded body; and crystallizing heat treatment to obtain a glass ceramic molded body from the compact of crystalline glass particles.

[0012] In the manufacturing method of the present invention, the 3D printed object may include crystalline glass particles such as SiO2-Al2O3-K2O-based crystalline glass particles or SiO2-Li2O-based crystalline glass particles.

[0013] In the manufacturing method of the present invention, the 3D printed object may be a crystalline glass particle with an average particle size (d(0.5)) measured by a particle size analyzer of up to 10㎛.

[0014] In the manufacturing method of the present invention, the 3D printed object may contain crystalline glass particles in an amount of 60 to 80 weight percent relative to the total weight of the object.

[0015] In one embodiment of the present invention, the degreasing step may be performed such that the weight reduction rate relative to the 3D printed object is 20 to 40%.

[0016] In one embodiment of the present invention, the step of crystallizing heat treatment may be performed such that the volume shrinkage rate relative to the compact of crystalline glass particles is 0.5 to 2.5%.

[0017] In one embodiment of the present invention, the step of crystallizing heat treatment may be performed by a method comprising the steps of: first heat treating a compact of crystalline glass particles at a first temperature of at least 280°C; second heat treating at a second temperature higher than the first temperature; and third heat treating at a third temperature higher than the second temperature.

[0018] As a more specific example, the first heat treatment may be performed at 280 to 320°C for 10 minutes to 2 hours, the second heat treatment may be performed at 400°C to less than 700°C for 10 minutes to 2 hours, and the third heat treatment may be performed at 700°C or higher to 980°C or lower for 5 minutes to 1 hour.

[0019] As an alternative example, the crystallization heat treatment step may be performed without undergoing the first heat treatment and the second heat treatment, by increasing the temperature at a rate of 2°C / min to 20°C / min up to the third heat treatment temperature range and maintaining it for 5 minutes to 1 hour.

[0020] The present invention also provides a glass ceramic molded body obtained by degreasing and crystallizing a molded body by 3D printing, comprising a crystalline phase dispersed within a glass matrix, wherein the crystalline phase is not present in the 3D printed molded body.

[0021] In the glass ceramic molded body according to the present invention, the crystalline phase may include a lithium silicate-based crystalline phase, and more preferably, the main crystalline phase may include lithium disilicate; and the secondary crystalline phase may include one or more selected from α-quartz, low-α-cristobalite, or lithium phosphate.

[0022] A glass ceramic molded body according to one embodiment of the present invention may have a degree of crystallinity of 30 to 70%.

[0023] The glass ceramic molded body according to the present invention may have a light transmittance of 10 to 40% at 550 nm for a specimen with a thickness of 1.2 mm.

[0024] The glass ceramic molded body according to the present invention may have a biaxial bending strength of 200 to 320 MPa for a specimen with a thickness of 1.2 mm.

[0025] Another example of the present invention provides a 3D printed object comprising an organic binder and crystalline glass particles.

[0026] In a 3D printed structure according to one example of the present invention, the crystalline glass particles may include SiO2-Al2O3-K2O-based crystalline glass particles or SiO2-Li2O-based crystalline glass particles.

[0027] In a 3D printed structure according to one example of the present invention, the crystalline glass particles may have an average particle size (d(0.5)) measured by a particle size analyzer within 10 μm.

[0028] In a 3D printed product according to an example of the present invention, crystalline glass particles may be included in an amount of 60 to 80 weight percent based on the total weight of the product.

[0029] According to the present invention, unlike the method of manufacturing a ceramic or glass ceramic molded body through a conventional additive manufacturing process, in which a final molded body is obtained through densification from a powder-molded body made of ceramic and / or glass ceramic particles, crystallization and densification are performed from a powder-molded body of crystalline glass particles, thereby enabling the production of a glass ceramic molded body with a relatively small shrinkage rate in terms of process.

[0030] FIG. 1 is a graph of the XRD results of a product that has undergone the process of first crystallization heat treatment to third crystallization heat treatment according to one embodiment of the present invention, and

[0031] FIG. 2 is an XRD result graph of a product (specimen no. 11) that has undergone a third crystallization heat treatment according to one embodiment of the present invention, and

[0032] FIG. 3 is a graph showing the light transmittance of a glass ceramic molded body that has undergone crystallization heat treatment according to one embodiment of the present invention.

[0033] The foregoing and additional aspects of the present invention will become more apparent through the preferred embodiments described below. The following description is to provide a detailed explanation so that those skilled in the art can easily understand and reproduce the present invention through such embodiments.

[0034] In one embodiment of the present invention, a method for manufacturing a glass ceramic molded body is provided, comprising the steps of: obtaining a 3D printed molded body comprising an organic binder and crystalline glass particles; degreasing to obtain a compact of crystalline glass particles from the 3D printed molded body; and crystallizing heat treatment to obtain a glass ceramic molded body from the compact of crystalline glass particles.

[0035] 3D printing technology is fundamentally based on three-dimensional digital models, which are generated through CAD or acquired through digital scanners. 3D printing methods can be defined as photopolymerization (PP), material extrusion (ME), binder jetting (BJ), material jetting (MJ), direct energy deposition (DED), powder bed fusion (PBF), and sheet lamination (SL). In one embodiment of the present invention, the step of obtaining a 3D printed object is not limited to these various methods and will be understood as a 3D printed result without such limitation.

[0036] However, if the 3D printing result, that is, the 3D printed object, comprises an organic binder and crystalline glass particles, it should be understood as being equivalent to the scope intended by the present invention in terms of the process following the step of obtaining the 3D printed object.

[0037] In the description above and below, the 'organic binder' can facilitate 3D printing by slurrying the ceramic. Preferably, it may be selected from (meth)acrylate-based monomers and oligomers containing unsaturated double bonds.

[0038] Accordingly, an organic binder according to one embodiment of the present invention comprises hydroxyethyl methacrylate (HEMA), 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (Bis-GMA), triethylene glycol dimethacrylate (TEGDMA), diurethane dimethacrylate, urethane dimethacrylate (UDMA), biphenyl dimethacrylate (BPDM), n-tolyglycine-glycidylmethacrylate (NTGE), and polyethylene glycol It may be at least one selected from the group consisting of dimethacrylate (polyethylene glycol dimethacrylate, PEG-DMA) and oligocarbonate dimethacrylic esters, 1,6-hexanediol dimethacrylate (HDDA), trimethylolpropane triacrylate (TMPTA), and bisphenol A diglycidyl methacrylate ethoxylated (Bis-EMA).

[0039] A ceramic 3D printed structure according to one embodiment of the present invention requires a ceramic content of at least 40 vol%, and accordingly, the viscosity of the slurry becomes very high, and it is desirable to use a binder that undergoes an immediate curing reaction due to light scattering of the filler. As an example, HDDA and / or TEPTA having high reactivity to polymerization and low viscosity characteristics may be used, but are not limited thereto.

[0040] In addition, since the ceramic 3D printed model according to one embodiment of the present invention ultimately burns out (BBO) all the organic binder used, the final physical properties of the ceramic 3D printed model are not affected by the organic binder. However, a minimum strength capable of maintaining its structure and shape in the green body state immediately after printing must be ensured so that deformation and defects do not occur during the debinding process. UDMA is desirable because it possesses strong strength characteristics and can play a role in providing the minimum strength mentioned above. Additionally, Bis-EMA resin has characteristics of lower strength and viscosity than UDMA and is a binder with high stability when polymerized; it is desirable to add it to control curing reactivity, but it is not limited thereto.

[0041] In order to produce a ceramic slurry having minimum strength, slurry flowability, and appropriate photocurability, an organic binder according to one embodiment of the present invention may preferably be used by mixing 25 to 40 weight% HDDA, 30 to 45 weight% TMPTA, 5 to 15 weight% UDMA, and 15 to 30 weight% Bis-EMA.

[0042] In the descriptions above and below, 'crystalline glass' may be defined as glass intended to form a crystalline phase within a glass matrix by controlling the composition and heat treatment process of the glass.

[0043] In addition, in the descriptions above and below, 'crystalline glass particles' may be defined as including both powder and granular glass particles intended to form a crystalline phase within a glass matrix by controlling the composition and heat treatment process of the glass.

[0044] The method for manufacturing a glass ceramic molded body according to the present invention does not impose limitations on the method of obtaining a 3D printed molded body through various methods, but rather includes crystalline glass particles within the molded body so that densification and crystallization occur simultaneously through subsequent post-processing, thereby lowering the volume shrinkage rate and obtaining a high-strength glass ceramic molded body when manufacturing a final molded body through 3D printing using ceramic or glass ceramic particles.

[0045]

[0046] In the descriptions above and below, the crystalline glass particles include SiO2-Al2O3-K2O-based crystalline glass particles or SiO2-Li2O-based crystalline glass particles, but are not limited thereto.

[0047] In addition, the crystalline glass particles may be desirable in that the average particle size (d(0.5)) measured by a particle size analyzer is within 10 μm, preferably 0.1 to 8 μm, and more preferably 0.5 to 5 μm, in order to prevent the problem of increased viscosity and the problem of hindering microdeposition when manufacturing a 3D printed object, and subsequently to achieve the degree of crystallization with the desired strength and transmittance when manufacturing a glass ceramic molded body.

[0048] Here, the particle size analyzer can be specifically identified as the Mastersizer from Marlvern Instruments.

[0049]

[0050] It may be desirable for these crystalline glass particles to be included in an amount of 60 to 80 weight percent of the total weight of 100 weight percent of the molded object in terms of achieving dispersibility and mechanical properties of the final molded object when obtaining a 3D printed object.

[0051] A 3D printed object containing an organic binder and crystalline glass particles is obtained, and then a glass ceramic molded body is manufactured through a post-processing process,

[0052] Specifically, first, a degreasing step is performed to obtain a compact of crystalline glass particles from a 3D printed object.

[0053] The degreasing step is a heat treatment process that removes various organic materials, such as organic binders other than crystalline glass particles contained in the 3D printed object. The temperature can be set over a wide range considering the organic binder used, and the degreasing efficiency can be increased by controlling the heat treatment temperature and time.

[0054] The degreasing step of the present invention is part of the crystallization heat treatment process below, in which degreasing is performed first during the crystallization heat treatment, and sintering proceeds at a higher crystallization heat treatment temperature. That is, degreasing and initial sintering occur during the first heat treatment, degreasing is completed during the second heat treatment, and final sintering is achieved through the third heat treatment. Therefore, it goes without saying that the temperature of the degreasing step can be understood as the initial sintering temperature of the crystallization heat treatment temperature below. However, it is acceptable as long as the degreasing step proceeds to a level where a certain weight loss rate is satisfied.

[0055] As a specific example, if the degreasing step is performed such that the weight reduction rate relative to the weight of the 3D printed object is 20 to 40%, preferably 30 to 35%, it can be considered that a compact of the desired crystalline glass particles has been obtained.

[0056] Next, a crystallization heat treatment step is performed to obtain a glass ceramic molded body from a compact of crystalline glass particles.

[0057] In general, in ceramic printing using ceramic particles or glass ceramic particles, a sintering process is performed to obtain a ceramic molded body or a glass ceramic molded body after obtaining a compact of ceramic particles or glass ceramic particles. This is a process that densifies the ceramic particles or glass ceramic particles, and in obtaining the desired final molded body based on this densification, the volume shrinkage rate is high and the strength may not be sufficient compared to the result obtained through machining based on a bulky structure.

[0058] In contrast, according to the present invention, the process of obtaining a glass ceramic molded body from a compact of crystalline glass particles, rather than a compact of ceramic particles or glass ceramic particles, involves crystallization accompanied by the formation of a crystalline phase within the glass particles as well as densification between the crystalline glass particles, thereby enabling the production of a glass ceramic molded body with a low volume shrinkage rate and high strength compared to a degreased 3D printed object.

[0059] The step of crystallizing heat treatment of the degreased 3D printed object is determined by considering the composition of crystalline glass particles contained in the 3D printed object and the transmittance and mechanical strength of the final molded body, and in general, it may be preferable to perform the crystallization heat treatment step such that the volume shrinkage rate of the glass ceramic molded body relative to the crystalline glass particle compact is 0.5 to 2.5%.

[0060] According to one embodiment of the present invention, the step of crystallizing heat treatment may be performed by a method comprising the steps of performing a first heat treatment on a compact of crystalline glass particles at a first temperature of at least 280°C, a second heat treatment at a second temperature higher than the first temperature, and a third heat treatment at a third temperature higher than the second temperature. More specifically, the first heat treatment may be performed at 280 to 320°C for 10 minutes to 2 hours, the second heat treatment may be performed at 400°C to less than 700°C for 10 minutes to 2 hours, and the third heat treatment may be performed at 700°C or higher to 980°C or lower for 5 minutes to 1 hour. It may be preferable to perform such crystallizing heat treatment by taking into account the minimum temperature range for crystallization and the maximum temperature at which the glass ceramic molded body is remelted.

[0061] If the above third heat treatment is performed at less than 700℃, the transmittance and strength of the glass ceramic molded body may be low, and if performed at more than 980℃, deformation may occur, so it is preferable to perform it at 700℃ or higher and 980℃ or lower.

[0062] Alternatively, the crystallization heat treatment step may be performed without undergoing the first and second heat treatments, by increasing the temperature at a rate of 2°C / min to 20°C / min up to the third heat treatment temperature range and maintaining it for 5 minutes to 1 hour, wherein the term "third heat treatment temperature range" refers to a range within the range of the third heat treatment temperature and is not necessarily limited to meaning the same temperature range.

[0063] As a specific example, a 3D printed mold comprising 60 to 80 weight% of SiO2-Li2O-based crystalline glass particles and 20 to 40 weight% of an organic binder out of 100 weight% of the total weight of the mold was degreased (weight loss rate before and after degreased was 20 to 40%), and then a first heat treatment was performed at 280 to 320°C for 10 minutes to 2 hours, a second heat treatment was performed at 400 to less than 700°C for 10 minutes to 2 hours, and a third heat treatment was performed at 700°C or higher to 980°C for 10 minutes to 1 hour for crystallization heat treatment. When the result was confirmed through XRD analysis, it was confirmed that a glass ceramic molded body was obtained in which a crystalline phase exists, unlike the SiO2-Li2O-based crystalline glass particles before heat treatment (Fig. 1).

[0064] In addition, the above 3D printed mold was degreased (weight loss rate before and after degreased is 20 to 40%), and then crystallization heat treatment was performed according to the alternative method described above (without undergoing the first and second heat treatments, the temperature was increased at a rate of 2℃ / min to 20℃ / min and maintained for 5 minutes to 1 hour). When the results were confirmed through XRD analysis, it was confirmed that a glass ceramic molded body having a crystalline phase was obtained, unlike the SiO2-Li2O-based crystalline glass particles before heat treatment (Fig. 2).

[0065] In the description above and below, the crystalline glass particles may be obtained by melting a crystalline glass composition, water-quenching the glass melt to obtain a glass molded body of a certain size, and then first crushing the glass.

[0066] As a preferred example, the crystalline glass composition may be a SiO2-Li2O-based crystalline glass composition, and the specific composition may comprise 60 to 85 wt% SiO2, 10 to 15 wt% Li2O, 1 to 15 wt% Al2O3, and 2 to 6 wt% of one or more selected from P2O5, ZrO2, and TiO2 as a nucleating agent. Preferably, it may comprise a metal oxide such as an alkali metal oxide or a divalent metal oxide. Examples of preferred metal oxides include an alkali metal oxide selected from K2O, Na2O, and mixtures thereof, and more preferably, the crystalline glass composition may comprise both K2O and Na2O. In addition, the crystalline glass composition may include a divalent metal oxide selected from the group consisting of MgO, CaO, SrO, BaO, ZnO, and mixtures thereof, and more preferably, may include a divalent metal oxide selected from the group consisting of ZnO, SrO, and mixtures thereof.

[0067] From these results, the present invention provides a glass ceramic molded body comprising a crystalline phase dispersed within a glass matrix by degreasing and crystallizing a molded body produced by 3D printing, wherein the crystalline phase is not present in the 3D printed molded body prior to degreasing and crystallizing heat treatment.

[0068] In the obtained glass ceramic molded body, the crystalline phase is a lithium silicate-based crystalline phase, preferably comprising lithium disilicate as the main crystalline phase in terms of strength; and preferably comprising one or more selected from α-quartz, low-α-cristobalite, or lithium phosphate as the secondary crystalline phase.

[0069] In addition, it is desirable for the obtained glass ceramic molded body to have a degree of crystallization of 30 to 70% to achieve appropriate strength and light transmittance. In the above and below descriptions, the degree of crystallization will be understood as a value automatically calculated through XRD analysis.

[0070] In the description above and below, XRD analysis will be understood as the result of analysis using an X-ray diffraction analyzer (D / MAX-2500, Rigaku, Japan; Cu Kα (40 kV, 60 mA), scan rate: 6° min, 2θ: 10~70 (degree), Rigaku, Japan).

[0071] In the step of degreasing and crystallizing heat treatment of a 3D printed object containing crystalline glass particles, a final glass ceramic molded body having various strengths and light transmittances can be obtained by controlling the temperature, holding time, and heating rate. For example, a 3D printed object containing SiO2-Li2O-based crystalline glass particles and an organic binder was degreasing (weight loss rate before and after degreasing is 20 to 40%), and then crystallized heat treatment was performed according to the alternative method described above (shrinkage rate relative to volume after degreasing is 0.5 to 2.5%). The light transmittance of the resulting objects was measured and the results are shown in FIG. 3.

[0072] In the descriptions above and below, light transmittance was measured using a UV-visible spectrometer (UV-2401PC, Shimadzu, Japan).

[0073] From this, it can be confirmed that the glass ceramic molded body according to one embodiment of the present invention has a light transmittance of 10 to 40% at 550 nm for a specimen with a thickness of 1.2 mm, and it can be expected that the molded body can be utilized for various purposes within this range of light transmittance.

[0074] In addition, a glass ceramic molded body according to one embodiment of the present invention may have a biaxial bending strength of 200 to 320 MPa for a specimen with a thickness of 1.2 mm, and the desired strength can be controlled by controlling the maximum temperature, holding time, and heating rate of the heat treatment temperature during the crystallization heat treatment step. For example, if the third heat treatment is performed at 700°C, the biaxial bending strength may be 200 MPa, and if performed at 980°C, the biaxial bending strength may be 320 MPa.

[0075] The biaxial flexural strength of the glass ceramic molded body manufactured including all of the first to third heat treatment processes for crystallization and the glass ceramic molded body manufactured through the third heat treatment process all showed a value of at least 315 MPa, and their XRD results are as shown in FIG. 1 and FIG. 2 (specimen number 11), respectively, and the XRD results of other specimens were omitted.

[0076] In addition, for various samples such as those shown in Fig. 3, glass ceramic molded bodies with biaxial flexural strength ranging from as low as 205 MPa to as high as 320 MPa could be obtained. The results of specimen numbers 5 to 17 shown in Fig. 3 were manufactured by controlling the heating rate in the range of 2°C / min to 20°C, the maximum temperature in the range of 820 to 870°C, and the holding time in the range of 5 minutes to 1 hour, and more specifically, each specimen was manufactured under the conditions of Table 1 below.

[0077] Specimen Maximum Temperature Heating Rate Holding Time 5845℃ 2℃ / min 5 min 6845℃ 20℃ / min 5 min 7870℃ 20℃ / min 5 min 8870℃ 20℃ / min 40 min 9820℃ 2℃ / min 10 min 10820℃ 20℃ / min 10 min 11845℃ 2℃ / min 40 min 12820℃ 2℃ / min 40 min 13820℃ 20℃ / min 5 min 14845℃ 20℃ / min 40 min 15820℃ 20℃ / min 40 min 16870℃ 2℃ / min 5 min 17820℃ 2℃ / min 5 min

[0078] Through the results of the above-described embodiments, the present invention also proposes a 3D printed body comprising an organic binder and crystalline glass particles in order to obtain a glass ceramic molded body with low volume shrinkage and high strength through 3D printing. As described above, the crystalline glass particles may include SiO2-Al2O3-K2O-based crystalline glass particles or SiO2-Li2O-based crystalline glass particles, and the crystalline glass particles may have an average particle size (d(0.5)) measured by a particle size analyzer of up to 10 μm, preferably 0.1 to 8 μm, and most preferably 0.5 to 5 μm. Including crystalline glass particles having such an average particle size can prevent the problem of increased viscosity of the 3D printed product and the problem of hindering microdeposition, and can subsequently be desirable in terms of achieving a degree of crystallization with the desired strength and transmittance when manufacturing a glass ceramic molded body.

[0079] In addition, it may be preferable for the crystalline glass particles to be included in an amount of 60 to 80 weight percent of the total weight of the molded product.

[0080]

[0081] In the description above and below, the glass ceramic molded body is not particularly limited in its use and may be, for example, a dental prosthesis such as a crown, inlay, onlay, veneer, bridge, etc. In particular, the examples described above were performed as examples of obtaining a glass ceramic molded body that is a crown-shaped prosthesis, but are not limited thereto.

[0082] In addition to dental prostheses, the glass ceramic molded body according to the present invention can be utilized in photosensitive glass ceramics, micro-patterns / substrates (support members, EUV, substrates within devices), sensors, displays, coatings, semiconductors / electronic devices, etc. Furthermore, through photosensitive glass ceramics, it can be applied to micro-optical elements, optical data storage devices, semiconductor fields, laser processing and micro-pattern processing, fiber optic sensors, biomedical devices, decorative glass, electronics / communications, optical control windows, anti-counterfeiting materials, etc.

[0083] Although the present invention has been described with reference to one embodiment, this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom.

[0084] The present invention relates to a glass ceramic molded body and a method for manufacturing the same, and more specifically, to a method for producing a high-strength glass ceramic molded body with a low shrinkage rate and a simplified process, and to a molded body obtained therefrom.

[0085] According to the present invention, unlike the method of manufacturing a ceramic or glass ceramic molded body through a conventional additive manufacturing process, in which a final molded body is obtained through densification from a powder-molded body made of ceramic and / or glass ceramic particles, crystallization and densification are performed from a powder-molded body of crystalline glass particles, thereby enabling the production of a glass ceramic molded body with a relatively small shrinkage rate in terms of process.

Claims

1. A step of obtaining a 3D printed object comprising an organic binder and crystalline glass particles; A step of degreasing to obtain a compact of crystalline glass particles from a 3D printed object; and A step comprising crystallization heat treatment to obtain a glass ceramic molded body from a compact of crystalline glass particles, Method for manufacturing a glass ceramic molded body.

2. In claim 1, the crystalline glass particles are characterized by comprising SiO2-Al2O3-K2O-based crystalline glass particles or SiO2-Li2O-based crystalline glass particles. Method for manufacturing a glass ceramic molded body.

3. In claim 1, the crystalline glass particles are characterized by having an average particle size (d(0.5)) measured by a particle size analyzer within a maximum of 10㎛. Method for manufacturing a glass ceramic molded body.

4. The crystalline glass particles according to claim 1, characterized in that they are included in an amount of 60 to 80 weight percent of the total weight of the 3D printed object. Method for manufacturing a glass ceramic molded body.

5. In claim 1, the degreasing step is characterized by being performed such that the weight reduction rate relative to the weight of the 3D printed object is 20 to 40%. Method for manufacturing a glass ceramic molded body.

6. In claim 1, the crystallization heat treatment step is characterized in that the volume shrinkage rate of the glass ceramic molded body relative to the shrinkage rate of the crystalline glass particle compact is 0.5 to 2.5%. Method for manufacturing a glass ceramic molded body.

7. The step of crystallization heat treatment according to claim 1 or 6 is characterized in that it is performed by a method comprising the steps of: first heat treating a crystalline glass particle compact at a first temperature of at least 280°C; second heat treating at a second temperature higher than the first temperature; and third heat treating at a third temperature higher than the second temperature. Method for manufacturing a glass ceramic molded body.

8. In claim 7, the first heat treatment of the crystallization heat treatment step is performed at a first temperature of 280 to 320°C for 10 minutes to 2 hours, the second heat treatment is performed at a second temperature of 400 to less than 700°C for 10 minutes to 2 hours, and the third heat treatment is performed at a third temperature of 700°C or higher to 980°C or lower for 10 minutes to 1 hour. Method for manufacturing a glass ceramic molded body.

9. In claim 8, the crystallization heat treatment step is characterized by being performed by increasing the temperature at a rate of 2℃ / min to 20℃ / min to within the third temperature range of the third heat treatment without undergoing the first heat treatment and the second heat treatment, and maintaining it for 5 minutes to 1 hour. Method for manufacturing a glass ceramic molded body.

10. A glass ceramic molded body obtained by degreasing and crystallizing a 3D printed body comprising an organic binder and crystalline glass particles, wherein The above glass ceramic molded body comprises a crystalline phase dispersed within a glass matrix, and The above crystalline phase is not present in the 3D printed object prior to degreasing and crystallization heat treatment, Glass ceramic molded body.

11. A glass ceramic molded body according to claim 10, characterized in that the crystalline phase comprises a lithium silicate-based crystalline phase.

12. A glass ceramic molded body according to claim 10 or 11, characterized in that the crystalline phase comprises lithium disilicate as the main crystalline phase; and comprises one or more selected from α-quartz, low-α-cristobalite, or lithium phosphate as the minor crystalline phase.

13. The glass ceramic molded body according to claim 10, characterized in that the glass ceramic molded body has a degree of crystallinity of 30 to 70%.

14. The glass ceramic molded body according to claim 10, characterized in that the glass ceramic molded body has a light transmittance of 10 to 40% at 550 nm for a specimen with a thickness of 1.2 mm.

15. The glass ceramic molded body according to claim 10, characterized in that the glass ceramic molded body has a biaxial bending strength of 200 to 320 MPa for a specimen with a thickness of 1.2 mm.

16. A 3D printed object comprising an organic binder and crystalline glass particles.

17. A 3D printed object according to claim 16, characterized in that the crystalline glass particles comprise SiO2-Al2O3-K2O-based crystalline glass particles or SiO2-Li2O-based crystalline glass particles.

18. A 3D printed object according to claim 16, characterized in that the crystalline glass particles have an average particle size (d(0.5)) measured by a particle size analyzer of up to 10 µm.

19. A 3D printed object according to claim 16, characterized in that crystalline glass particles are included in an amount of 60 to 80 weight percent of the total weight of the object.

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