# US 7,744,711 B2 · Manufacturing method of ceramic slurry, green sheet and multilayer ceramic device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,744,711 B2 - Document ID: US7744711B2 - Status: Granted - Kind: B2 - Application number: 10/571,542 - Filed: 2004-08-31 - Published: 2006-12-14 - Granted: 2010-06-29 - Earliest claimed: 2003-09-12 - Assignees: TDK Corporation - Inventors: Hisashi Kobayashi; Shigeki Satou - Web page: https://patentgrep.com/patent/US7744711B2 ## CPC - C04B 35/62635: {Mixing details} - B32B 18/00: Layered products essentially comprising ceramics, e.g. refractory products - C04B 35/4682: {based on BaTiO3 perovskite phase} - C04B 35/62625: {Wet mixtures} - C04B 35/6263: {characterised by their solids loadings, i.e. the percentage of solids} - C04B 35/63: using additives specially adapted for forming the products {, e.g.. binder binders} - H01G 4/12: Ceramic dielectrics {(H01G4/085 takes precedence)} - C04B 2235/3206: Magnesium oxides or oxide-forming salts thereof - C04B 2235/3215: Barium oxides or oxide-forming salts thereof - C04B 2235/3236: Alkaline earth titanates - C04B 2235/3239: Vanadium oxides, vanadates or oxide forming salts thereof, e.g. magnesium vanadate - C04B 2235/3241: Chromium oxides, chromates, or oxide-forming salts thereof - C04B 2235/3436: Alkaline earth metal silicates, e.g. barium silicate - C04B 2235/3454: Calcium silicates, e.g. wollastonite - Y10T 428/252: Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.] - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - H01G: CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE (selection of specified materials as dielectric H01B3/00; capacitors having potential barriers H10D1/62, H10K10/10) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A manufacturing method of ceramic slurry being used for producing a green sheet which can have a smooth surface, exhibits a satisfactory sheet strength, and is excellent in workability such as releasing, a green sheet produced by the use of the slurry produced by the method, and a multilayer ceramic device produced by the use of the green sheet is provided. According to the present invention, a manufacturing method of ceramic slurry at least comprising a ceramic powder and a binder resin solution, wherein a high-pressure dispersing treatment of the ceramic powder and a lacquer for preliminary addition, which is a part of the binder resin solution, is carried out so that a shearing rate is set to 1×107 to 1×108 [1/sec] to prepare a preliminary slurry, and at least a lacquer for post-addition, which a high-pressure dispersing treatment is not applied, is added to the preliminary slurry which a high-pressure dispersing treatment is applied. ## Claims ### Claim 1 A manufacturing method of ceramic slurry at least comprising a ceramic powder and a binder resin solution, wherein a high-pressure dispersing treatment of the ceramic powder and a lacquer for preliminary addition, which is a part of the binder resin solution, is carried out so that a shearing rate is set to 1×107 to 1×108 [1/sec] to prepare a preliminary slurry, at least a lacquer for post-addition, which a high-pressure dispersing treatment is not applied, is added to the preliminary slurry which a high-pressure dispersing treatment is applied, and an amount of the binder resin contained in the lacquer for preliminary addition is less than 10 wt% and 1 wt% or more with respect to the whole amount of resin contained in the finally obtained ceramic slurry. ### Claim 2 (depends on 1) The manufacturing method of ceramic slurry as set forth in claim 1, wherein, when applying the high pressure dispersing treatment, shearing stress is applied to the preliminary slurry so that the shearing rate is set to 2×107 to 1×108 [1/sec]. ### Claim 3 (depends on 1) The manufacturing method of ceramic slurry as set forth in claim 1, wherein a binder resin of the binder resin solution is polyvinyl butyral resin or polyvinyl acetal resin. ### Claim 4 (depends on 3) The manufacturing method of ceramic slurry as set forth in claim 3, wherein degree of polymerization of the binder resin is at least 1000 and at most 2600. ### Claim 5 (depends on 1) The manufacturing method of ceramic slurry as set forth in claim 1, wherein the high pressure dispersing treatment is applied by pouring the preliminary slurry from a wide path to a narrow path under a high pressure. ### Claim 6 (depends on 1) The manufacturing method of ceramic slurry as set forth in claim 1, wherein a particle size of the ceramic powder is 0.01 μm to 0.5 μm. ### Claim 7 (depends on 1) The manufacturing method of ceramic slurry as set forth in claim 1, wherein at least a part of dispersants and/or plasticizers is added to the preliminary slurry before applying the high pressure dispersing treatment. ### Claim 8 (depends on 1) The manufacturing method of ceramic slurry as set forth in claim 1, wherein at least a part of dispersants and/or plasticizers is added to the preliminary slurry after applying the high pressure dispersing treatment. ### Claim 9 (depends on 1) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 1. ### Claim 10 (depends on 9) A multilayer ceramic device manufactured by the steps of: stacking the green sheet as set forth in claim 9 to obtain a green chip, and firing the green chip. ### Claim 11 (depends on 9) A multilayer ceramic capacitor manufactured by the steps of: stacking the green sheet as set forth in claim 9 to obtain a green chip, and firing the green chip. ### Claim 12 (depends on 2) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 2. ### Claim 13 (depends on 3) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 3. ### Claim 14 (depends on 4) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 4. ### Claim 15 (depends on 5) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 5. ### Claim 16 (depends on 6) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 6. ### Claim 17 (depends on 7) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 7. ### Claim 18 (depends on 8) A green sheet manufactured by using the ceramic slurry obtained by the manufacturing method of ceramic slurry as set forth in claim 8.