# US 7,745,534 B2 · Process for the production of ceramic green films with acetalized polyvinyl alcohols > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,745,534 B2 - Document ID: US7745534B2 - Status: Granted - Kind: B2 - Application number: 11/745,725 - Filed: 2007-05-08 - Published: 2007-11-15 - Granted: 2010-06-29 - Earliest claimed: 2006-05-10 - Assignees: Kuraray Europe GmbH - Inventors: Michael Frank; Robert Fuss - Web page: https://patentgrep.com/patent/US7745534B2 ## CPC - C04B 35/63416: {Polyvinylalcohols [PVA]; Polyvinylacetates} - C04B 35/111: Fine ceramics - C04B 35/46: based on titanium oxides or titanates (containing also zirconium or hafnium oxides, zirconates or hafnates C04B35/49) - C04B 35/468: based on barium titanates - C04B 35/486: Fine ceramics - C04B 35/495: based on vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates - C04B 35/581: based on aluminium nitride - C04B 35/6263: {characterised by their solids loadings, i.e. the percentage of solids} - C04B 35/6264: {Mixing media, e.g. organic solvents} - C04B 35/6342: {Polyvinylacetals, e.g. polyvinylbutyral [PVB]} - C04B 2235/3258: Tungsten oxides, tungstates, or oxide-forming salts thereof - C04B 2235/5409: expressed by specific surface values - C04B 2235/5445: submicron sized, i.e. from 0,1 to 1 micron - C04B 2235/6025: Tape casting, e.g. with a doctor blade - 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 ## Abstract Acetalized polyvinyl alcohols having a high residual polyvinyl acetate content are suitable as use as dispersing agents in the production of ceramic green films. ## Claims ### Claim 1 A process for the production of ceramic green films or ceramic moulded bodies, said process comprising casting and drying a suspension comprising one or more inorganic pigments, one or more organic solvents, one or more binders, one or more plasticizers, and one or more dispersing agents, wherein an acetalized polyvinyl alcohol with a vinyl acetate content of 8 to 50% by weight and a degree of polymerization Pw of 100 to 1200 is used as said dispersing agent, wherein said acetalized polyvinyl alcohol does not contain 1-alkyl vinyl alcohol units. ### Claim 2 (depends on 1) A process according to claim 1, wherein said suspension contains 0.1 to 10% by weight of said acetalized polyvinyl alcohol. ### Claim 3 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a vinyl alcohol content of 10 to 35% by weight. ### Claim 4 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a degree of polymerization of 100 to 1000. ### Claim 5 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a viscosity, determined according to DIN 53015, of 2 to 500 mPas. ### Claim 6 (depends on 1) A process according to claim 1, wherein one or several aldehydes selected from formaldehyde, acetaldehyde, propanal, butanal, isobutanal, pentanal, hexanal, heptanal, octanal, nonanal, isononanal, and decanal are used for the acetalation of said polyvinyl alcohol. ### Claim 7 (depends on 1) A process according to claim 1, wherein polyvinyl butyral is used as said acetalized polyvinyl alcohol. ### Claim 8 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a vinyl acetate content of 10 to 50% by weight. ### Claim 9 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a vinyl acetate content of 10 to 30% by weight. ### Claim 10 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has vinyl alcohol content of 10 to 35% by weight. ### Claim 11 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a vinyl alcohol content of 11 to 27% by weight. ### Claim 12 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a degree of polymerization Pw of 100-1000. ### Claim 13 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohols has a viscosity of 2 to 200 mPas determined in a 10% solution in ethanol at 20° C. ### Claim 14 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a vinyl acetate content of 10 to 50% by weight, and a vinyl alcohol content of 10 to 35% by weight. ### Claim 15 (depends on 1) A process according to claim 1, wherein said acetalized polyvinyl alcohol has a degree of acetalation of 20 to 60% by weight. ### Claim 16 In a process for production of ceramic green films or ceramic moulded bodies, said process comprising casting and drying a suspension, the improvement wherein said suspension contains, as a dispersing agent, an acetalized polyvinyl alcohol having a vinyl acetate content of 8 to 50% by weight and a degree of polymerization of 100 to 1200, wherein said acetalized polyvinyl alcohol does not contain 1-alkyl vinyl alcohol units. ### Claim 17 A suspension composition comprising one or more inorganic pigments, one or more organic solvents, one or more binders, one or more plasticizers, and one or more dispersing agents, wherein an acetalized polyvinyl alcohol with a vinyl acetate content of 8 to 50% by weight and a degree of polymerization Pw of 100 to 1200 is used as said dispersing agent, wherein said acetalized polyvinyl alcohol does not contain 1-alkyl vinyl alcohol units. ### Claim 18 (depends on 17) A suspension according to claim 17, wherein said suspension contains 0.1 to 10% by weight of said acetalized polyvinyl alcohol. ### Claim 19 (depends on 18) A suspension according to claim 18, wherein said suspension contains 1 to 8% by weight of said acetalized polyvinyl alcohol. ### Claim 20 (depends on 17) A suspension according to claim 17, wherein said one or more pigments are selected from Al2O3, BaTiO3, W oxides, ZrO2, TiO2 or aluminum nitrite, said one or more solvents are selected from methanol, toluene, methyl ethyl ketone, paraffins, and isopropanol, and said one or more plasticizers are selected from phthalates, adipates, polyethylene glycols, phosphoric acid esters, citric acid esters or esterified polyethylene glycols. ### Claim 21 (depends on 17) A suspension according to claim 17, wherein the binder and dispersing agent are the same material. ### Claim 22 (depends on 17) A suspension according to claim 17, wherein said suspension contains a mixture of dispersants and said mixture of dispersants contains at least 50% by weight of said acetalized polyvinyl alcohol. ### Claim 23 (depends on 17) A suspension according to claim 17, wherein said one or more binders are selected from polyvinyl butyrals, polyacrylates and said acetalized polyvinyl alcohols. ### Claim 24 (depends on 17) A suspension according to claim 17, wherein said suspension contains a mixture of binders containing one or more polyvinyl butyrals and one or more of said acetalized polyvinyl alcohols, wherein the proportion of polyvinyl butyrals is less than 50% by weight. ### Claim 25 (depends on 17) A suspension according to claim 17, wherein the amount of pigments(s) in the suspension is 40-80% by weight, the amount of solvent(s) in the suspension is 15-35% by weight, the amount of plasticizer(s) in the suspension is 1-10% by weight, the amount of dispersion agent(s) in the suspension is 0.5-5% by weight, and the amount of binder(s) in the suspension is 0.1-10% by weight. ### Claim 26 (depends on 17) A suspension according to claim 17, wherein said acetalized polyvinyl alcohol has a vinyl acetate content of 10 to 50% by weight, and a vinyl alcohol content of 10 to 35% by weight. ### Claim 27 (depends on 17) A suspension according to claim 17, wherein said acetalized polyvinyl alcohol has a degree of acetalation of 20 to 60% by weight.