Abstract:
PURPOSE: A manufacturing method of a perovskite powder is provided to obtain perovskite powder with excellent dielectric property and electrical performance by manufacturing core-shell structure perovskite powder with a different chemical composition and a matching structure, by using hydrothermal synthesis. CONSTITUTION: A perovskite powder consists of a core portion(1) and shell portion(2). The core portion has a perovskite structure represented by ABO3. The shell portion has a matching structure with the core part, has a different chemical composition from the core portion, and is doped on the core portion. The perovskite atom is doped by one or more selected from aluminum(Al), yttrium(Y), dysprosium(Dy), holmium(Ho), magnesium(Mg), manganese(Mn), vanadium(V), zirconium(Zr) and calcium(Ca). A manufacturing method of the perovskite powder comprises a step of forming a perovskite nuclei; a step of growing the perovskite nuclei in a hydrothermal reactor; a step of preparing a mixture solution by injecting a metal salt aqueous solution into the reactor; and a step of obtaining a perovskite powder by heating the mixture solution.
Abstract:
PURPOSE: A dielectric composition is provided to have an excellent reliability, dielectric property and electrical property by forming a doped layer on the surface in synthesis of perovskite powder using the hydrothermal synthesis method. CONSTITUTION: A dielectric composition comprises a ceramic body including a dielectric layer including peovskite powder(1) with a doped layer(2), on the surface, doped with rare earth resources and at least one material selected from the group consisting of alkaline-earth resources and boron group series; and an internal electrode layer arranged to place the dielectric layer in the interval and to face each other. The dielectric layer includes multiple dielectric grains with a doped layer, on the surface, doped with rare earth resources and at least one material selected from the group consisting of alkaline-earth resources and boron group series.
Abstract:
PURPOSE: A shutter device and handy camera with the same are provided to save the time to manufacture a camera by simplifying the inside structure of a shutter device. CONSTITUTION: A shutter device comprises a housing(210) and a driving part(201). A light through hole(211), through which light passes, is formed in the housing. The driving part is installed within the housing and opens and closes the light through hole. The driving part comprises a first shutter blade(230), a second shutter blade(240), a first electromagnet(280), a second electromagnet, and a third electromagnet(260). A permanent magnet is respectively one end of the first shutter blade. When, the first shutter blade and the second shutter blade close the light through hole, the first electromagnet and the second electromagnet is respectively installed close to the location of the permanent magnet. When the first shutter blade and the second shutter blade open the light through hole, the third electromagnet is closely installed in the location of the permanent magnet.
Abstract:
The present invention relates to a dielectric composition and a method for manufacturing the same. The dielectric composition according to the present invention comprises: a first perovskite powder for a core represented by ABO_3 and 1-70 parts by weight of a second peroveskite powder for a shell represented by ABO_3 for 100 parts by weight of the first perovskite powder and having 1/10-1/3 of an average particle diameter compared to the first perovskite powder, wherein the second perovskite powder comprises pores and the volume fraction of the pores is 3-50 vol%. According to the present invention, provided are the dielectric composition with the excellent dielectric properties and electric properties and a method for manufacturing the same.
Abstract:
The present invention relates to a production method of barium titanate and barium titanate powder produced by the same. The production method of high crystalline barium titanate by the present invention comprises the following steps: a step for preparing a barium hydroxide raw material with ionized barium by heating; a step for preparing a titanium raw material which is dispersed in acid or a base; a step for obtaining barium titanate seeds by mixing the barium hydroxide raw material and titanium raw material, and making the barium hydroxide raw material react with the titanium raw material; and mixing the barium titanate seeds with pure water and a sintering promotion agent for growing particles. The barium titanate powder produced by the production method of barium titanate has excellent particle distribution and low sintering initiating temperature for reducing problems of separation or connection degradation when the barium titanate powder is applied to laminated ceramic electronic components. [Reference numerals] (S1) Prepare a barium hydroxide raw material; (S2) Prepare a titanium raw material; (S3) Mix the barium hydroxide raw material and titanium raw material and make the barium hydroxide raw material react with the titanium raw materia at high temperatures(form barium titanate seeds); (S4) Mix the barium titanate seeds with a sintering promotion agent; (S5) Barium titanate seeds grain growth at high temperature and high pressure; (S6) Produce barium titanate powder
Abstract:
PURPOSE: A manufacturing method of perovskite powder is provided to obtain perovskite powder of highly crystalline granules by forming at least one film layer selected from a group consisting of salt which includes sulfide and sulfur when composing perovskite powder using hydrothermal synthesis method. CONSTITUTION: A perovskite powder formed a covering layer in surface. The covering layer is at least one which is selected from group consisting of salt which includes the sulfide and sulfur. The sulfide is ammonium sulfate. Salt including the sulfur is at least one selected from a group consisted of phosphate and acetate. A manufacturing method of the perovskite powder comprises following steps. (a) Form perovskite particle nuclear by mixing metal salt and metal oxide. (b) Mix more than one selected from a group consisting of the perovskite particle nuclear, sulfide dissolved in purified water and salt comprises sulfur. And (c) obtain perovskite powder by grain growing in a hydrothermal treatment. [Reference numerals] (AA) Step of forming perovskite particle nuclear by mixing metal salt and metal oxide; (BB) Step of mixing the perovskite particle nuclear and one or more selected from a group consisting of salts containing sulfide and sulfur dissolved in purified water; (CC) Step of grain growing the mixture with hydrothermal treatment and obtaining perovskite powder with the surface on which one or more film layers selected from a group consisting of the salts containing sulfide and sulfur are formed;