JP2018197180A - Production method of sintered body and sintered body - Google Patents
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本発明は、無機粉末を含む粉体を焼成することにより焼結体を得る、焼結体の製造方法及び焼結体に関する。 The present invention relates to a sintered body manufacturing method and a sintered body, in which a sintered body is obtained by firing a powder containing an inorganic powder.
従来より、セラミック粉末、ガラス粉末等の無機粉末を含む粉体を所望の形状の成形物に成形し、前記成形物を焼成することで焼結体を製造することが行われている。 Conventionally, a sintered body is manufactured by forming a powder containing an inorganic powder such as ceramic powder or glass powder into a molded product having a desired shape and firing the molded product.
前記成形物を焼成する際には、粉体の粒界面に存在する空隙に起因する気泡が発生するが、得られた焼結体の内部に気泡が存在すると、焼結体の強度が低下するといった問題が生じる。
また、無機粉末として、ガラス粉末と蛍光体粉末を含んだ粉体を焼成することにより得られ、照射された所定の波長の光を前記所定の波長とは異なる波長の光に変換する焼結体の場合、内部に気泡が存在すると、強度低下に加えて光の変換効率が低下するといった問題が生じる。
When the molded product is fired, bubbles are generated due to voids present at the grain boundaries of the powder. If bubbles are present inside the obtained sintered body, the strength of the sintered body is reduced. Problems arise.
Also, a sintered body obtained by firing a powder containing glass powder and phosphor powder as inorganic powder, and converting irradiated light having a predetermined wavelength into light having a wavelength different from the predetermined wavelength. In this case, if bubbles exist inside, there arises a problem that the light conversion efficiency is lowered in addition to the strength reduction.
従って、従来においては、例えば特許文献１に記載されるように、ガラス粉末と蛍光体粉末との混合物を減圧雰囲気下にて焼成することにより、焼成時に発生する気泡を焼結体の内部から除去することが行われている。 Therefore, conventionally, as described in Patent Document 1, for example, by firing a mixture of glass powder and phosphor powder in a reduced-pressure atmosphere, bubbles generated during firing are removed from the inside of the sintered body. To be done.
しかし、前述のように、ガラス粉末と蛍光体粉末との混合物を減圧雰囲気下にて焼成した場合においても気泡を完全に除去することはできず、焼結体の内部にある程度の気泡が残存した状態となる。このように、焼結体の内部に気泡が残存した状態では、焼結体の強度を十分に高めることが困難であった。また、透明度の高い焼結体を得ることができず、焼結体における光の変換効率を十分に高めることが困難であった。 However, as described above, even when the mixture of the glass powder and the phosphor powder is fired in a reduced pressure atmosphere, the bubbles cannot be completely removed, and some bubbles remain in the sintered body. It becomes a state. As described above, it is difficult to sufficiently increase the strength of the sintered body in a state in which bubbles remain in the sintered body. In addition, a sintered body with high transparency cannot be obtained, and it has been difficult to sufficiently increase the light conversion efficiency in the sintered body.
そこで、本発明においては、無機粉末を含む粉体を焼成することによって焼結体を得る際に、焼結体内部に残存する気泡の、焼結体に対して占める割合を十分に小さくすることができる焼結体の製造方法及び焼結体を提供するものである。 Therefore, in the present invention, when a sintered body is obtained by firing a powder containing inorganic powder, the ratio of bubbles remaining in the sintered body to the sintered body is sufficiently reduced. A method for producing a sintered body and a sintered body are provided.
上記課題を解決する焼結体の製造方法及び焼結体は、以下の特徴を有する。
即ち、本発明に係る焼結体の製造方法は、請求項１記載の如く、無機粉末を含む粉体を所望の形状に成形することにより成形物を得る成形工程と、前記成形物を焼成して焼結体を得る焼成工程と、前記焼成工程の後に、前記成形物を冷却する冷却工程とを備え、前記焼成工程は、前記成形物を１気圧未満の圧力である第１圧力の雰囲気下で焼成する第１焼成工程と、前記第１焼成工程中に焼成雰囲気の真空破壊を行って、前記成形物を前記第１圧力よりも高い圧力である第２圧力の雰囲気下で焼成する第２焼成工程とを備える。
A method for manufacturing a sintered body and a sintered body that solve the above problems have the following characteristics.
That is, the method for producing a sintered body according to the present invention includes a molding step of obtaining a molded product by molding a powder containing an inorganic powder into a desired shape, and firing the molded product. A sintering step for obtaining a sintered body, and a cooling step for cooling the molded product after the firing step, wherein the firing step is performed under an atmosphere of a first pressure that is a pressure of less than 1 atm. A first firing step for firing at a second, and a vacuum firing of the firing atmosphere during the first firing step, and a second firing for firing the molded article in a second pressure atmosphere that is higher than the first pressure. And a firing step.
また、請求項２記載の如く、前記無機粉末が、ガラス粉末である。 According to a second aspect of the present invention, the inorganic powder is a glass powder.
また、請求項３記載の如く、前記第１焼成工程において、前記成形物を、前記ガラス粉末の屈伏点以下の温度から、前記ガラス粉末の屈伏点よりも高い温度まで昇温する。 According to a third aspect of the present invention, in the first firing step, the molded product is heated from a temperature below the yield point of the glass powder to a temperature higher than the yield point of the glass powder.
また、請求項４記載の如く、前記真空破壊は、前記ガラス粉末の屈伏点よりも高い温度にて行う。 Further, as described in claim 4, the vacuum break is performed at a temperature higher than the yield point of the glass powder.
また、請求項５記載の如く、前記第１圧力は、５００Ｐａ以下である。 According to a fifth aspect of the present invention, the first pressure is 500 Pa or less.
また、請求項６記載の如く、前記第２圧力は、０．８気圧以上である。 According to a sixth aspect of the present invention, the second pressure is 0.8 atm or more.
また、請求項７記載の如く、前記焼成工程の前に、前記成形物を加熱して前記成形物から水分を除去する乾燥工程を有する。 According to a seventh aspect of the present invention, the method includes a drying step of heating the molded product to remove moisture from the molded product before the firing step.
また、請求項８記載の如く、前記粉体は、さらにセラミック粉末を含む。 In addition, as described in claim 8, the powder further includes a ceramic powder.
また、請求項９記載の如く、前記粉体は、さらに蛍光体粉末を含む。 According to a ninth aspect of the present invention, the powder further includes a phosphor powder.
また、請求項１０記載の如く、前記粉体は、さらにセラミック粉末及び蛍光体粉末を含む。 According to a tenth aspect of the present invention, the powder further includes a ceramic powder and a phosphor powder.
また、請求項１１記載の如く、前記粉体は、平均粒子径（Ｄ５０）が１００μｍ以下である粒度を有する。 In addition, as described in claim 11, the powder has a particle size having an average particle diameter (D 50 ) of 100 μm or less.
また、本発明に係る焼結体は、請求項１２記載の如く、気泡の数が、２ケ／ｍｍ２以下である。 In addition, the sintered body according to the present invention has a number of bubbles of 2 / mm 2 or less as described in claim 12.
本発明によれば、焼結体内部に残存する気泡の、焼結体に対して占める割合が十分に小さい焼結体を得ることができる。 According to the present invention, it is possible to obtain a sintered body in which the ratio of bubbles remaining in the sintered body to the sintered body is sufficiently small.
次に、本発明に係る焼結体の製造方法を実施するための形態について説明する。 Next, the form for implementing the manufacturing method of the sintered compact concerning this invention is demonstrated.
本発明に係る焼結体の製造方法は、無機粉末を含む粉体を所望の形状に成形することにより成形物を得る成形工程と、前記成形物を焼成して焼結体を得る焼成工程と、前記焼成工程の後に、前記成形物を冷却する冷却工程とを備え、前記焼成工程は、前記成形物を１気圧未満の圧力である第１圧力の雰囲気下で焼成する第１焼成工程と、前記第１焼成工程中に焼成雰囲気の真空破壊を行って、前記成形物を前記第１圧力よりも高い圧力である第２圧力の雰囲気下で焼成する第２焼成工程とを備えるものである。 The method for producing a sintered body according to the present invention includes a molding step for obtaining a molded product by molding a powder containing inorganic powder into a desired shape, and a firing step for firing the molded product to obtain a sintered body. A cooling step for cooling the molded product after the firing step, the firing step firing the molded product in an atmosphere of a first pressure that is a pressure of less than 1 atmosphere; A second firing step of performing a vacuum break of the firing atmosphere during the first firing step and firing the molded product in an atmosphere of a second pressure that is higher than the first pressure.
前記粉体に含まれる無機粉末としては、ガラス粉末を用いることができる。なお、ガラス粉末のガラス組成は特に限定されるものではないが、例えば、ＳｉＯ２−Ｂ２Ｏ３系、ＳｉＯ２−Ｂ２Ｏ３−Ａｌ２Ｏ３系、ＳｉＯ２−Ｂ２Ｏ３−ＺｎＯ系、ＳｉＯ２−Ｂ２Ｏ３−ＴｉＯ２−ＺｎＯ−Ｎｂ２Ｏ５系、及びＳｎＯ−Ｐ２Ｏ５−Ｂ２Ｏ３系等の組成系を有するガラス粉末を用いることができる。 Glass powder can be used as the inorganic powder contained in the powder. Although not particularly limited in glass composition of the glass powder, for example, SiO 2 -B 2 O 3 based, SiO 2 -B 2 O 3 -Al 2 O 3 based, SiO 2 -B 2 O 3 - A glass powder having a composition system such as a ZnO system, a SiO 2 —B 2 O 3 —TiO 2 —ZnO—Nb 2 O 5 system, and a SnO—P 2 O 5 —B 2 O 3 system can be used.
前記粉体は、ガラス粉末に加えて、アルミナ（Ａｌ２Ｏ３）等のセラミック粉末を含んでいてもよい。
また、前記粉体は、ガラス粉末に加えて、蛍光体粉末を含んでいてもよい。
さらに、前記粉体は、ガラス粉末に加えて、セラミック粉末及び蛍光体粉末を含んでいてもよい。
The powder may contain ceramic powder such as alumina (Al 2 O 3 ) in addition to glass powder.
The powder may contain a phosphor powder in addition to the glass powder.
Further, the powder may contain ceramic powder and phosphor powder in addition to glass powder.
なお、前記粉体は、平均粒子径（Ｄ５０）が１００μｍ以下である粒度を有することが好ましい。より好ましくは平均粒子径（Ｄ５０）が８０μｍ以下であり、さらに好ましくは平均粒子径（Ｄ５０）が６０μｍ以下であり、最も好ましくは平均粒子径（Ｄ５０）が５０μｍ以下である。平均粒子径（Ｄ５０）が上記上限を超えると、所望する粉体形状への成形が困難になるおそれがある。平均粒子径（Ｄ５０）の下限は特に限定されないが、生産性の観点から０．５μｍ程度とすることができる。 Incidentally, the powder has an average particle diameter (D 50) preferably has a particle size is 100μm or less. More preferably, the average particle size (D 50 ) is 80 μm or less, more preferably the average particle size (D 50 ) is 60 μm or less, and most preferably the average particle size (D 50 ) is 50 μm or less. If the average particle diameter (D 50 ) exceeds the above upper limit, it may be difficult to form a desired powder shape. The lower limit of the average particle diameter (D 50 ) is not particularly limited, but can be about 0.5 μm from the viewpoint of productivity.
蛍光体粉末を構成する蛍光体は、ある波長の光を吸収し、吸収した光の波長とは異なる波長の光（即ち蛍光）を放出する物質であり、例えば２５０ｎｍ〜５００ｎｍの波長の領域に発光ピークを有する光を照射すると、波長が３８０ｎｍ〜７８０ｎｍの可視光域に蛍光を発する。 The phosphor constituting the phosphor powder is a substance that absorbs light of a certain wavelength and emits light having a wavelength different from the wavelength of the absorbed light (that is, fluorescence). When light having a peak is irradiated, fluorescence is emitted in a visible light region having a wavelength of 380 nm to 780 nm.
蛍光体粉末としては、例えば可視光域に発光ピークを有する無機蛍光体粉末を用いることができる。無機蛍光体粉末としては、例えば酸化物、窒化物、酸窒化物、塩化物、酸塩化物、硫化物、酸硫化物、ハロゲン化物、カルコゲン化物、アルミン酸塩、ハロリン酸塩化物、ＹＡＧ系化合物等からなるものがある。 As the phosphor powder, for example, an inorganic phosphor powder having an emission peak in the visible light region can be used. Examples of the inorganic phosphor powder include oxides, nitrides, oxynitrides, chlorides, acid chlorides, sulfides, oxysulfides, halides, chalcogenides, aluminates, halophosphates, and YAG compounds. There is something that consists of etc.
ガラス粉末及び蛍光体粉末を含んだ粉体、並びにガラス粉末、セラミック粉末及び蛍光体粉末を含んだ粉体を焼成することにより得られる焼結体は、例えば紫外（２５０ｎｍ〜４００ｎｍの波長）や青色（４００ｎｍ〜５００ｎｍの波長）の励起光を照射すると、少なくともその一部を吸収して可視光域の蛍光に変換する発光色変換部材として用いることができる。このような発光色変換部材は、例えば、板状、柱状、筒状、半球状等のそれ自身が特定の形状を有する部材、及び基材表面に形成された被膜として構成することができる。 A sintered body obtained by firing a powder containing glass powder and phosphor powder, and a powder containing glass powder, ceramic powder and phosphor powder is, for example, ultraviolet (wavelength of 250 nm to 400 nm) or blue When irradiated with excitation light (wavelength of 400 nm to 500 nm), it can be used as an emission color conversion member that absorbs at least a part thereof and converts it into fluorescence in the visible light range. Such a luminescent color conversion member can be configured as a member having a specific shape such as a plate shape, a columnar shape, a cylindrical shape, or a hemispherical shape, and a coating formed on the surface of the substrate.
次に、少なくともガラス粉末を含んだ粉体の一例である、ガラス粉末、セラミック粉末、及び蛍光体粉末を含んだ粉体を焼成することにより焼結体を製造する際のフローについて説明する。 Next, a flow for producing a sintered body by firing a powder containing glass powder, ceramic powder, and phosphor powder, which is an example of powder containing at least glass powder, will be described.
図１に示すように、まず、ガラス粉末、セラミック粉末、及び蛍光体粉末を混合して（Ｓ０１）、ガラス粉末、セラミック粉末、及び蛍光体粉末を含んだ粉体を得る。
次に、前記粉体を所望の形状に成形して、成形物を形成する（Ｓ０２）。つまり、粉体を所望の形状に成形することにより成形物を得る成形工程を実施する。なお、成形物の成形方法には、粉体のままプレスする成形方法や、粉体、有機溶剤、樹脂バインダー等からなるスラリーをシート状に成形する方法を用いることができる。
As shown in FIG. 1, first, glass powder, ceramic powder, and phosphor powder are mixed (S01) to obtain powder containing glass powder, ceramic powder, and phosphor powder.
Next, the powder is formed into a desired shape to form a molded product (S02). That is, a molding step is performed in which a molded product is obtained by molding the powder into a desired shape. In addition, the shaping | molding method of a molded object can use the shaping | molding method pressed with powder, and the method of shape | molding the slurry which consists of a powder, an organic solvent, a resin binder, etc. in a sheet form.
成形工程の後に、得られた成形物を加熱して、成形物から水分や有機溶剤、樹脂バインダー等を除去する乾燥工程を実施する（Ｓ０３）。乾燥工程においては、炉内温度が所定の温度になるように制御した加熱炉に成形物を入れることにより、成形物を加熱する。
乾燥工程において成形物が加熱されると、成形物に付着している水分が蒸発して水蒸気となり、成形物から除去される。
After the molding step, the obtained molded product is heated to carry out a drying step for removing moisture, organic solvent, resin binder and the like from the molded product (S03). In the drying step, the molded product is heated by placing the molded product in a heating furnace controlled so that the furnace temperature becomes a predetermined temperature.
When the molded product is heated in the drying process, the water adhering to the molded product evaporates to become water vapor and is removed from the molded product.
図２には、加熱炉の制御温度プロファイルが２点鎖線で示されており、加熱炉における実際の炉内温度のプロファイルが実線で示されており、加熱炉における炉内雰囲気の圧力プロファイルが鎖線にて示されている。
本実施形態の乾燥工程においては、加熱炉の制御温度は２００℃に設定されている。加熱炉における実際の炉内温度は、乾燥工程が開始された時刻Ｔ０から上昇し、少なくとも乾燥工程が終了する時刻Ｔ１においては、炉内温度は２００℃に達する。また、乾燥工程は、炉内雰囲気が大気圧となる大気圧雰囲気下にて行われる。
In FIG. 2, the control temperature profile of the heating furnace is shown by a two-dot chain line, the actual furnace temperature profile in the heating furnace is shown by a solid line, and the pressure profile of the furnace atmosphere in the heating furnace is shown by a chain line. Is shown.
In the drying process of this embodiment, the control temperature of the heating furnace is set to 200 ° C. The actual furnace temperature in the heating furnace rises from time T0 when the drying process is started, and the furnace temperature reaches 200 ° C. at least at time T1 when the drying process ends. Further, the drying step is performed in an atmospheric pressure atmosphere in which the furnace atmosphere becomes atmospheric pressure.
乾燥工程が終了する時刻Ｔ１になると、加熱炉の炉内雰囲気を昇温させるとともに減圧して（Ｓ０４）、成形物を１気圧（１．０１３×１０５Ｐａ）未満の圧力である第１圧力の雰囲気下で焼成する（Ｓ０５）。加熱炉の炉内雰囲気の昇温は、加熱炉内に設置されたヒータにより行い、加熱炉の炉内雰囲気の減圧は、加熱炉に接続された減圧ポンプにより行う。 At time T1 when the drying step is finished, the furnace atmosphere in the heating furnace is heated and depressurized (S04), and the first pressure is a pressure less than 1 atm (1.013 × 10 5 Pa). Is fired in an atmosphere of (S05). The temperature in the furnace atmosphere of the heating furnace is raised by a heater installed in the heating furnace, and the pressure in the furnace atmosphere in the heating furnace is reduced by a pressure reducing pump connected to the heating furnace.
成形物を第１圧力の雰囲気下で焼成する工程は第１焼成工程であり、第１焼成工程においては、成形物を、ガラス粉末の屈伏点以下の温度から、ガラス粉末の屈伏点よりも高い温度まで昇温される。
第１焼成工程においては、焼成雰囲気が１気圧未満の第１圧力に減圧されているため、成形物がガラス粉末の屈伏点以下の温度にあるときに、ガラス粉末、セラミック粉末、及び蛍光体粉末の粒界面に存在する空隙に含まれる大気成分が成形物内から容易に脱気される。
The step of firing the molded product in the atmosphere of the first pressure is the first firing step, and in the first firing step, the molded product is higher than the yield point of the glass powder from a temperature below the yield point of the glass powder. The temperature is raised to the temperature.
In the first firing step, since the firing atmosphere is depressurized to a first pressure of less than 1 atm, the glass powder, the ceramic powder, and the phosphor powder when the molding is at a temperature below the yield point of the glass powder. Atmospheric components contained in the voids existing at the grain interfaces are easily degassed from the molded product.
成形物に含まれる大気成分を脱気するといった観点からは、第１圧力は小さい方が有利である。従って、第１圧力は５００Ｐａ以下の圧力であることが好ましく、２０Ｐａ以下の圧力であるとより好ましく、１０Ｐａ以下の圧力であるとさらに好ましい。 From the viewpoint of degassing the atmospheric components contained in the molded product, it is advantageous that the first pressure is small. Therefore, the first pressure is preferably 500 Pa or less, more preferably 20 Pa or less, and even more preferably 10 Pa or less.
このように、成形物を１気圧未満となる第１圧力の雰囲気下にて焼成し、成形物に含まれる大気成分を脱気することにより、成形物がガラス粉末の屈伏点よりも高い温度に加熱されて軟化流動した際に、成形物内に残存する気泡を削減することが可能となっている。
この場合、第１圧力を５００Ｐａ以下の低い圧力とすることで、成形物内の大気成分を効果的に脱気して、残存する気泡を大きく削減することが可能となる。
In this way, the molded product is fired under an atmosphere of a first pressure that is less than 1 atm, and the atmospheric component contained in the molded product is degassed, so that the molded product has a temperature higher than the yield point of the glass powder. When heated and softened and flowed, it is possible to reduce bubbles remaining in the molded product.
In this case, by setting the first pressure to a low pressure of 500 Pa or less, it is possible to effectively deaerate atmospheric components in the molded product and greatly reduce the remaining bubbles.
また、第１焼成工程においては、成形物はガラス粉末の屈伏点以下の温度から加熱されるため、成形物が軟化流動する前に大気成分を脱気することができ、成形物内に残存する気泡の削減を効率的に行うことが可能となっている。
但し、ガラス粉末の屈伏点よりも高い温度に加熱されて軟化流動すると、成形物から完全に気泡を除去することは困難であり、多少の気泡が成形物内に残存することとなる。
In the first firing step, since the molded product is heated from a temperature below the yield point of the glass powder, atmospheric components can be degassed before the molded product softens and flows, and remains in the molded product. It is possible to efficiently reduce bubbles.
However, when heated to a temperature higher than the yield point of the glass powder and softened and flowed, it is difficult to completely remove the bubbles from the molded product, and some bubbles remain in the molded product.
本実施形態においては、加熱炉内における焼成雰囲気の圧力は、第１焼成工程の開始時刻となる時刻Ｔ１を経過した後、大気圧から４０Ｐａ程度まで一気に低下する。その後、一旦１００Ｐａ程度まで上昇した後、再度低下して１０Ｐａ以下の圧力に達する。
第１焼成工程において、加熱炉内の焼成雰囲気が４０Ｐａ程度まで低下した後に１００Ｐａ程度まで上昇するのは、以下の理由による。つまり、成形物には乾燥工程で除去しきれなかった水分が残存しており、その残存している水分が、焼成雰囲気が減圧されることにより蒸発して水蒸気になる。これにより、４０Ｐａ程度まで低下した焼成雰囲気の圧力が１００Ｐａ程度まで上昇する。
In the present embodiment, the pressure of the firing atmosphere in the heating furnace is rapidly reduced from atmospheric pressure to about 40 Pa after the time T1 that is the start time of the first firing step has elapsed. Then, after raising to about 100 Pa once, it falls again and reaches a pressure of 10 Pa or less.
In the first firing step, the firing atmosphere in the heating furnace rises to about 100 Pa after being lowered to about 40 Pa for the following reason. In other words, moisture that could not be removed in the drying process remains in the molded product, and the remaining moisture evaporates into steam by reducing the firing atmosphere. As a result, the pressure of the firing atmosphere, which has been reduced to about 40 Pa, rises to about 100 Pa.
但し、成形物に付着している水分の多くは、第１焼成工程の前に行われる乾燥工程にて除去されているため、第１焼成工程において成形物に残存している水分は僅かであり、減圧能力が小さな減圧ポンプを用いた場合でも、第１焼成工程における焼成雰囲気の圧力を所望の第１圧力にまで到達させることが可能となっている。 However, since most of the water adhering to the molded product is removed in the drying step performed before the first firing step, the moisture remaining in the molded product in the first firing step is very small. Even when a decompression pump having a small decompression capacity is used, the pressure of the firing atmosphere in the first firing step can reach the desired first pressure.
第１焼成工程においては、成形物の昇温速度が時刻Ｔ１から時刻Ｔ２までの間と、時刻Ｔ２から時刻Ｔ３までの間とで異なっている。具体的には、第１焼成工程が開始した直後の時刻Ｔ１から時刻Ｔ２までの間よりも、その後の時刻Ｔ２から時刻Ｔ３までの間の方が、昇温速度が小さくなっている。 In the first firing step, the temperature rising rate of the molded product is different between time T1 and time T2 and between time T2 and time T3. Specifically, the rate of temperature increase is lower between time T2 and time T3 than after time T1 and time T2 immediately after the start of the first firing step.
これは、第１焼成工程に要する時間を短くするためには、成形物の昇温速度を大きくした方が有利ではあるが、昇温速度を大きくし過ぎると、加熱される成形物のガラス粉末の屈伏点よりも高い温度への到達時刻が早くなって第１焼成工程の時間が短くなるため、焼成雰囲気の減圧速度が間に合わなくなり、所望の圧力まで減圧することが困難になるためである。
従って、時刻Ｔ２から時刻Ｔ３までの間の昇温速度を小さくして、第１焼成工程に要する時間を適度に確保し、第１焼成工程における焼成雰囲気を所望の圧力まで減圧することを可能としている。
なお、本実施形態では、昇温速度が切り替えられる時刻Ｔ２は、成形物がガラス粉末のガラス転位点となる温度まで加熱される時刻に設定されている。
In order to shorten the time required for the first firing step, it is advantageous to increase the temperature rising rate of the molded product. However, if the temperature rising rate is excessively increased, the glass powder of the molded product to be heated. This is because the time to reach a temperature higher than the yield point becomes earlier and the time of the first firing step is shortened, so that the decompression speed of the firing atmosphere is not in time, and it is difficult to decompress to the desired pressure.
Therefore, it is possible to reduce the temperature increase rate from time T2 to time T3, to ensure an appropriate time for the first firing step, and to reduce the firing atmosphere in the first firing step to a desired pressure. Yes.
In the present embodiment, the time T2 at which the temperature raising rate is switched is set to the time when the molded product is heated to a temperature at which the glass transition point of the glass powder is reached.
第１焼成工程においては、成形物は、ガラス粉末の屈伏点以下の温度からガラス粉末の屈伏点よりも高い温度まで昇温され、さらにガラス粉末の軟化点よりも高い温度まで加熱される。
例えば成形物に含まれるガラス粉末の軟化点が８３５℃である場合、時刻Ｔ１において２００℃に加熱されている成形物は、時刻Ｔ３において８８０℃まで加熱される。
第１焼成工程は、時刻Ｔ１から時刻Ｔ３まで行われる。
In the first firing step, the molded product is heated from a temperature lower than the yield point of the glass powder to a temperature higher than the yield point of the glass powder, and further heated to a temperature higher than the softening point of the glass powder.
For example, when the softening point of the glass powder contained in the molded product is 835 ° C., the molded product heated to 200 ° C. at time T1 is heated to 880 ° C. at time T3.
The first firing step is performed from time T1 to time T3.
時刻がＴ３に達すると、加熱炉における焼成雰囲気の真空破壊を行って、焼成雰囲気の圧力を第１圧力よりも高い圧力である第２圧力まで上昇させる（Ｓ０６）。焼成雰囲気の真空破壊は、例えば減圧状態にある加熱炉内を大気に開放して、加熱炉内に大気を流入させることにより行われる。
その後、成形物を第２圧力の雰囲気下で焼成する（Ｓ０７）。第２圧力は、０．８気圧以上の圧力であることが好ましく、本実施形態においては、大気圧としている。
When the time reaches T3, vacuum firing of the firing atmosphere in the heating furnace is performed, and the pressure of the firing atmosphere is increased to a second pressure that is higher than the first pressure (S06). The vacuum destruction of the firing atmosphere is performed, for example, by opening the inside of a heating furnace in a reduced pressure state to the atmosphere and flowing the atmosphere into the heating furnace.
Thereafter, the molded product is fired under an atmosphere of the second pressure (S07). The second pressure is preferably a pressure of 0.8 atm or higher, and is set to atmospheric pressure in the present embodiment.
成形物を第２圧力の雰囲気下で焼成する工程は第２焼成工程であり、第２焼成工程は時刻Ｔ３から時刻Ｔ４まで行われる。第２焼成工程においては、成形物は第１焼成工程における加熱温度よりも高い温度に加熱され、例えば時刻Ｔ４において９３０℃程度まで加熱される。 The step of firing the molded product in the atmosphere of the second pressure is the second firing step, and the second firing step is performed from time T3 to time T4. In the second firing step, the molded product is heated to a temperature higher than the heating temperature in the first firing step, and is heated to, for example, about 930 ° C. at time T4.
第２焼成工程においては、成形物は、ガラス粉末の屈伏点よりも高い温度（本実施形態においては８８０℃）に加熱されて軟化した状態で、第１圧力よりも高い圧力である第２圧力にて焼成されるため、成形物内に残留している気泡が焼成雰囲気の圧力により圧縮されて、第１焼成工程におけるサイズよりも小さなサイズの気泡となる。
特に、第２圧力を０．８気圧以上の高い圧力とすることで、第１圧力と第２圧力との圧力差を大きくすることができ、成形物内に残留している気泡の圧縮度合を高めることができる。
In the second firing step, the molded product is heated to a temperature higher than the yield point of the glass powder (880 ° C. in the present embodiment) and softened, and the second pressure is higher than the first pressure. Therefore, the bubbles remaining in the molded product are compressed by the pressure of the firing atmosphere, and become bubbles having a size smaller than the size in the first firing step.
In particular, by setting the second pressure to a high pressure of 0.8 atm or higher, the pressure difference between the first pressure and the second pressure can be increased, and the degree of compression of bubbles remaining in the molded product can be increased. Can be increased.
第２焼成工程では、第１焼成工程において第１圧力にて焼成された際に成形物内に残留した気泡を、第２圧力にて焼成することで圧縮させるため、第１圧力と第２圧力との圧力差は大きい方が好ましい。 In the second firing step, the bubbles remaining in the molded product when fired at the first pressure in the first firing step are compressed by firing at the second pressure. The pressure difference between is larger.
具体的には、第１圧力が５００Ｐａ以下、且つ第２圧力が０．８気圧以上であることが好ましく、第１圧力が２０Ｐａ以下、且つ第２圧力が０．８気圧以上であることがより好ましく、第１圧力が１０Ｐａ以下、且つ第２圧力が０．８気圧以上であることがなお好ましい。
さらには、第１圧力が５００Ｐａ以下、且つ第２圧力が１気圧であることが好ましく、第１圧力が２０Ｐａ以下、且つ第２圧力が１気圧であることがより好ましく、第１圧力が１０Ｐａ以下、且つ第２圧力が１気圧であることが特に好ましい。
Specifically, the first pressure is preferably 500 Pa or less and the second pressure is preferably 0.8 atm or more, and the first pressure is 20 Pa or less and the second pressure is 0.8 atm or more. Preferably, the first pressure is 10 Pa or less and the second pressure is 0.8 atm or more.
Furthermore, the first pressure is preferably 500 Pa or less and the second pressure is preferably 1 atm, the first pressure is 20 Pa or less and the second pressure is more preferably 1 atm, and the first pressure is 10 Pa or less. It is particularly preferable that the second pressure is 1 atm.
第１焼成工程の後に行われる焼成雰囲気の真空破壊は、ガラス粉末の屈伏点よりも高い温度にて行われるが、その温度はガラス粉末の軟化点よりも１００℃程度高い温度以下であることが好ましい。
これは、焼成雰囲気の真空破壊を行って成形物を第１圧力よりも高い第２圧力にて加圧して焼成する際に、成形物内の気泡を効果的に圧縮するためには成形物をガラス粉末の屈伏点よりも高い温度に加熱して軟化流動させることが好ましいが、成形物の温度がガラス粉末の軟化点よりも１００℃程度高い温度を超えると、成形物の流動度合が高くなり過ぎて、成形物の形状を保持できなくなるおそれがあるためである。また、成形物に含まれる蛍光体が熱により劣化するおそれがあるためである。
The vacuum break of the firing atmosphere performed after the first firing step is performed at a temperature higher than the yield point of the glass powder, but the temperature may be about 100 ° C. higher than the softening point of the glass powder. preferable.
This is because, in order to effectively compress the bubbles in the molded product, when the molded product is subjected to vacuum breakage in the firing atmosphere and pressed at a second pressure higher than the first pressure and fired. It is preferable to heat and soften the glass powder to a temperature higher than the yield point of the glass powder, but when the temperature of the molded product exceeds about 100 ° C. higher than the softening point of the glass powder, the flow rate of the molded product increases. This is because the shape of the molded product may not be maintained. Moreover, it is because the fluorescent substance contained in a molding may be deteriorated by heat.
時刻Ｔ４の経過後は、炉内雰囲気の温度を降温させて成形物を冷却する（Ｓ０８）。冷却された成形物は固化し、焼結体が得られる。時刻Ｔ４以降の、成形物を冷却して固化させる工程は冷却工程である。
本実施形態においては、冷却工程は、炉内雰囲気の圧力を、第２焼成工程と同じ大気圧に保持したままの状態で行われる。成形物は、炉内雰囲気を大気圧に保持した状態で冷却、固化されるため、残留している気泡が圧縮されて小さなサイズとなったままの状態で焼結体を得ることができる。
After the elapse of time T4, the temperature of the furnace atmosphere is lowered to cool the molded product (S08). The cooled molded product is solidified to obtain a sintered body. The process of cooling and solidifying the molded product after time T4 is a cooling process.
In the present embodiment, the cooling step is performed while maintaining the pressure in the furnace atmosphere at the same atmospheric pressure as in the second firing step. Since the molded product is cooled and solidified in a state in which the atmosphere in the furnace is maintained at atmospheric pressure, a sintered body can be obtained in a state where the remaining bubbles are compressed to a small size.
得られた焼結体は、残存する気泡が圧縮されて小さなサイズとなっているため、焼結体に対する気泡の占める割合が十分に小さくなっており、高い強度を有するとともに、透明度が高く光の変換効率に優れた焼結体となる。 In the obtained sintered body, since the remaining bubbles are compressed and have a small size, the ratio of the bubbles to the sintered body is sufficiently small, and has high strength, high transparency and high light intensity. It becomes a sintered body excellent in conversion efficiency.
本実施形態では、冷却工程における炉内雰囲気の圧力は、第２焼成工程における第２圧力と同じ大気圧に設定しているが、これに限るものではない。
つまり、冷却工程における圧力は、第１焼成工程における第１圧力よりも高い圧力であれば、第２焼成工程における第２圧力と異なる圧力に設定することも可能である。
但し、冷却工程においては、第２焼成工程で圧縮されて小さくなった気泡のサイズを保持したまま成形物を固化させるために、０．８気圧以上の圧力であることが好ましく、１気圧であることがより好ましい。
In the present embodiment, the pressure in the furnace atmosphere in the cooling step is set to the same atmospheric pressure as the second pressure in the second firing step, but is not limited thereto.
That is, the pressure in the cooling step can be set to a pressure different from the second pressure in the second firing step as long as the pressure is higher than the first pressure in the first firing step.
However, in the cooling step, in order to solidify the molded product while maintaining the size of the bubbles compressed and reduced in the second baking step, the pressure is preferably 0.8 atm or more, and preferably 1 atm. It is more preferable.
上述のように、本実施形態においては、ガラス粉末、セラミック粉末、及び蛍光体粉末を含んだ粉体を焼成することにより焼結体を製造する際のフローについて説明したが、当該フローは、ガラス粉末及び蛍光体粉末を含んだ粉体を焼成することにより焼結体を製造する際にも適用することができる。
この場合においても、得られた焼結体は、焼結体に対する気泡の占める割合が十分に小さくなっており、高い強度を有するとともに、透明度が高く光の変換効率に優れた焼結体となる。
As described above, in the present embodiment, the flow for producing a sintered body by firing a powder containing glass powder, ceramic powder, and phosphor powder has been described. The present invention can also be applied to the production of a sintered body by firing a powder containing powder and phosphor powder.
Even in this case, the obtained sintered body has a sufficiently small proportion of bubbles to the sintered body, and has a high strength and a high transparency and a high light conversion efficiency. .
さらに、当該フローは、ガラス粉末及びセラミック粉末を含んだ粉体を焼成することにより焼結体を製造する際にも適用することができる。
この場合、得られた焼結体は、焼結体に対する気泡の占める割合が十分に小さくなっており、高い強度を有する焼結体となる。
Furthermore, this flow can also be applied when a sintered body is produced by firing a powder containing glass powder and ceramic powder.
In this case, in the obtained sintered body, the ratio of bubbles to the sintered body is sufficiently small, and the sintered body has a high strength.
なお、高い強度を有し、蛍光体粉末を含む場合には、高い強度を有すると共に、透明度が高く光の変換効率に優れた焼結体とするには、焼結体に残存する気泡の数が、２ケ／ｍｍ２以下とする必要がある。好ましくは１ケ／ｍｍ２以下であり、より好ましくは０．５ケ／ｍｍ２以下であり、さらに好ましくは０．１ケ／ｍｍ２以下である。気泡の数が大きくなると、焼結体の強度が低下したり、蛍光体粉末を含む場合には、透明度が高く光の変換効率に優れた焼結体が得にくくなる。 In addition, when it has high intensity | strength and contains fluorescent substance powder, in order to make it a sintered compact with high intensity | strength and high transparency and excellent light conversion efficiency, the number of the bubbles which remain | survive in a sintered compact However, it is necessary to make it 2 or less / mm2. Preferably it is 1 piece / mm < 2 > or less, More preferably, it is 0.5 piece / mm < 2 > or less, More preferably, it is 0.1 piece / mm < 2 > or less. When the number of bubbles increases, the strength of the sintered body decreases or when a phosphor powder is included, it becomes difficult to obtain a sintered body with high transparency and excellent light conversion efficiency.
また、気泡の大きさは直径で１０μｍ以下であることが好ましい。より好ましくは５μｍ以下であり、さらに好ましくは３μｍ以下であり、最も好ましくは１μｍ以下である。気泡が大きくなりすぎると、焼結体の強度が低下したり、蛍光体粉末を含む場合には、透明度が高く光の変換効率に優れた焼結体が得にくくなる。 The size of the bubbles is preferably 10 μm or less in diameter. More preferably, it is 5 μm or less, more preferably 3 μm or less, and most preferably 1 μm or less. If the bubbles become too large, the strength of the sintered body is reduced, or when a phosphor powder is included, it becomes difficult to obtain a sintered body with high transparency and excellent light conversion efficiency.
Claims (12)
前記成形物を焼成して焼結体を得る焼成工程と、
前記焼成工程の後に、前記成形物を冷却する冷却工程とを備え、
前記焼成工程は、
前記成形物を１気圧未満の圧力である第１圧力の雰囲気下で焼成する第１焼成工程と、
前記第１焼成工程中に焼成雰囲気の真空破壊を行って、前記成形物を前記第１圧力よりも高い圧力である第２圧力の雰囲気下で焼成する第２焼成工程とを備える、
ことを特徴とする焼結体の製造方法。 A molding step of obtaining a molded product by molding a powder containing inorganic powder into a desired shape;
A firing step of firing the molded product to obtain a sintered body;
A cooling step for cooling the molded product after the firing step;
The firing step includes
A first firing step of firing the molded article in an atmosphere of a first pressure that is a pressure of less than 1 atmosphere;
Performing a vacuum break of the firing atmosphere during the first firing step, and firing the molded product in a second pressure atmosphere that is higher than the first pressure.
The manufacturing method of the sintered compact characterized by the above-mentioned.
ことを特徴とする請求項１に記載の焼結体の製造方法。 The inorganic powder is a glass powder;
The manufacturing method of the sintered compact of Claim 1 characterized by the above-mentioned.
ことを特徴とする請求項２に記載の焼結体の製造方法。 In the first firing step, the molded product is heated from a temperature below the yield point of the glass powder to a temperature higher than the yield point of the glass powder.
The manufacturing method of the sintered compact of Claim 2 characterized by the above-mentioned.
ことを特徴とする請求項２又は請求項３に記載の焼結体の製造方法。 The vacuum break is performed at a temperature higher than the yield point of the glass powder.
The manufacturing method of the sintered compact of Claim 2 or Claim 3 characterized by the above-mentioned.
ことを特徴とする請求項１〜請求項４の何れか一項に記載の焼結体の製造方法。 The first pressure is 500 Pa or less.
The manufacturing method of the sintered compact as described in any one of Claims 1-4 characterized by the above-mentioned.
ことを特徴とする請求項１〜請求項５の何れか一項に記載の焼結体の製造方法。 The second pressure is 0.8 atm or more.
The manufacturing method of the sintered compact as described in any one of Claims 1-5 characterized by the above-mentioned.
ことを特徴とする請求項１〜請求項６の何れか一項に記載の焼結体の製造方法。 Before the firing step, the drying step of heating the molded product to remove moisture from the molded product,
The manufacturing method of the sintered compact as described in any one of Claims 1-6 characterized by the above-mentioned.
ことを特徴とする請求項１〜請求項７の何れか一項に記載の焼結体の製造方法。 The powder further includes a ceramic powder,
The manufacturing method of the sintered compact as described in any one of Claims 1-7 characterized by the above-mentioned.
ことを特徴とする請求項１〜請求項７の何れか一項に記載の焼結体の製造方法。 The powder further includes a phosphor powder,
The manufacturing method of the sintered compact as described in any one of Claims 1-7 characterized by the above-mentioned.
ことを特徴とする請求項１〜請求項７の何れか一項に記載の焼結体の製造方法。 The powder further includes ceramic powder and phosphor powder,
The manufacturing method of the sintered compact as described in any one of Claims 1-7 characterized by the above-mentioned.
ことを特徴とする請求項１〜請求項１０の何れか一項に記載の焼結体の製造方法。 The powder has a particle size having an average particle size (D 50 ) of 100 μm or less.
The manufacturing method of the sintered compact as described in any one of Claims 1-10 characterized by the above-mentioned.
ことを特徴とする焼結体。 The number of bubbles is 2 / mm 2 or less,
A sintered body characterized by that.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5035209A (en) * | 1973-07-02 | 1975-04-03 | ||
| JPH0543271A (en) * | 1991-08-09 | 1993-02-23 | Tosoh Corp | Production of oxynitride glass |
| JP2003031117A (en) * | 2001-07-10 | 2003-01-31 | Nec Corp | Manufacturing method and manufacturing device of dielectric layer |
| JP2005235660A (en) * | 2004-02-20 | 2005-09-02 | Chugai Ro Co Ltd | Sealing treatment method and sealing treatment furnace of glass panel assembly |
| JP2009096653A (en) * | 2007-10-15 | 2009-05-07 | Panasonic Electric Works Co Ltd | Manufacturing method of color converting member |
| JP2013173643A (en) * | 2012-02-24 | 2013-09-05 | Sophia School Corp | Method for producing sintered body |
| JP2014073944A (en) * | 2012-10-05 | 2014-04-24 | Hitachi Metals Ltd | Method of producing silicon nitride sintered body |
| JP2015071699A (en) * | 2013-10-03 | 2015-04-16 | 日本電気硝子株式会社 | Wavelength conversion material, wavelength conversion member and light-emitting device |
-
2017
- 2017-05-24 JP JP2017102978A patent/JP6950279B2/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5035209A (en) * | 1973-07-02 | 1975-04-03 | ||
| JPH0543271A (en) * | 1991-08-09 | 1993-02-23 | Tosoh Corp | Production of oxynitride glass |
| JP2003031117A (en) * | 2001-07-10 | 2003-01-31 | Nec Corp | Manufacturing method and manufacturing device of dielectric layer |
| JP2005235660A (en) * | 2004-02-20 | 2005-09-02 | Chugai Ro Co Ltd | Sealing treatment method and sealing treatment furnace of glass panel assembly |
| JP2009096653A (en) * | 2007-10-15 | 2009-05-07 | Panasonic Electric Works Co Ltd | Manufacturing method of color converting member |
| JP2013173643A (en) * | 2012-02-24 | 2013-09-05 | Sophia School Corp | Method for producing sintered body |
| JP2014073944A (en) * | 2012-10-05 | 2014-04-24 | Hitachi Metals Ltd | Method of producing silicon nitride sintered body |
| JP2015071699A (en) * | 2013-10-03 | 2015-04-16 | 日本電気硝子株式会社 | Wavelength conversion material, wavelength conversion member and light-emitting device |
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