WO2004110954A1 - Method for producing ceramic green films for ceramic components - Google Patents

Method for producing ceramic green films for ceramic components Download PDF

Info

Publication number
WO2004110954A1
WO2004110954A1 PCT/DE2004/000777 DE2004000777W WO2004110954A1 WO 2004110954 A1 WO2004110954 A1 WO 2004110954A1 DE 2004000777 W DE2004000777 W DE 2004000777W WO 2004110954 A1 WO2004110954 A1 WO 2004110954A1
Authority
WO
WIPO (PCT)
Prior art keywords
dispersion
ceramic
acid
components
solvent mixture
Prior art date
Application number
PCT/DE2004/000777
Other languages
German (de)
French (fr)
Inventor
Stefan Henneck
Friedericke Lindner
Alfons Kelnberger
Huu Nguyen
Original Assignee
Robert Bosch Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Priority to US10/560,125 priority Critical patent/US7713896B2/en
Priority to JP2006515648A priority patent/JP2006527154A/en
Priority to EP04727226A priority patent/EP1633686A1/en
Publication of WO2004110954A1 publication Critical patent/WO2004110954A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/48—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates
    • C04B35/49—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates containing also titanium oxides or titanates
    • C04B35/491—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates containing also titanium oxides or titanates based on lead zirconates and lead titanates, e.g. PZT
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/62605—Treating the starting powders individually or as mixtures
    • C04B35/62625—Wet mixtures
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/62605—Treating the starting powders individually or as mixtures
    • C04B35/62625—Wet mixtures
    • C04B35/6264—Mixing media, e.g. organic solvents
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • C04B35/634—Polymers
    • C04B35/63404—Polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B35/63424—Polyacrylates; Polymethacrylates
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/638—Removal thereof
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/01—Manufacture or treatment
    • H10N30/05—Manufacture of multilayered piezoelectric or electrostrictive devices, or parts thereof, e.g. by stacking piezoelectric bodies and electrodes
    • H10N30/053—Manufacture of multilayered piezoelectric or electrostrictive devices, or parts thereof, e.g. by stacking piezoelectric bodies and electrodes by integrally sintering piezoelectric or electrostrictive bodies and electrodes
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/44—Metal salt constituents or additives chosen for the nature of the anions, e.g. hydrides or acetylacetonate
    • C04B2235/449—Organic acids, e.g. EDTA, citrate, acetate, oxalate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
    • C04B2235/602—Making the green bodies or pre-forms by moulding
    • C04B2235/6025—Tape casting, e.g. with a doctor blade
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/72—Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics
    • C04B2235/721—Carbon content
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/85—Piezoelectric or electrostrictive active materials
    • H10N30/853—Ceramic compositions
    • H10N30/8548—Lead-based oxides
    • H10N30/8554—Lead-zirconium titanate [PZT] based

Definitions

  • the invention relates generally to a method for producing green films for ceramic components, in particular multi-layer components according to the preamble of claim 1.
  • Ceramic production technology One focus in ceramic production technology is the development of new green body manufacturing processes. Examples of this are ceramic injection molding, gel casting or near-net shape technology. All processes require the use of large quantities of organic aids, e.g. Binders, lubricants or stabilizers that have to be removed from the green parts before or during the sintering process.
  • organic aids e.g. Binders, lubricants or stabilizers that have to be removed from the green parts before or during the sintering process.
  • the debinding process is on the one hand time and cost intensive, on the other hand it causes environmental pollution from the resulting, partly harmful degradation products.
  • Binder systems for ceramic green sheets based on polyacrylates and methacrylates are known and are used, for example, in the capacitor industry.
  • Aqueous dispersions of polyacrylates are usually used for the very thin capacitor foils (2 - 20 ⁇ m). With layer thicknesses from around 100 ⁇ m, aqueous systems are no longer economical due to the long drying times.
  • formulations with acrylate resins are derived from polyvinyl butyral (PVB) formulations and the corresponding known dispersants such as fish oil or phosphoric acid esters and solvent mixtures such as ethanol / toluene are used.
  • Ceramic, in particular piezoceramic components comprise several, in particular many layers (multi-layer or multi-layer components), they are for example as Actuators in piezo stacks (piezo stacks) can be used by achieving a low-inertia mechanical deflection of comparatively high force by means of voltage control, or can be used as a bending element by the voltage control causing a high mechanical deflection of less force, or they allow the generation of high electrical voltages or serve in corresponding devices the detection of mechanical or the generation of acoustic vibrations.
  • the noble metal electrodes allow the dispersants and binders used in the process of producing ceramic foils as well as the other organic additives and also the organic components of the screen printing metal paste to be thermally eliminated from the multilayer stacks in the air by depolymerization and oxidation, so that a sinter compaction at approx. 1100 up to 115O 0 C is made possible without reducing effects, for example due to remaining carbon residues, which have a negative effect on the properties of the ceramic as a result of reduction reactions.
  • piezo actuators with optimal properties of the ceramic are obtained, which are similar to those of one Conditions separate from the copper-containing electrode layer or even air-sintered piezoceramic layer are not inferior to or even exceed the composition in question.
  • a polyurethane dispersion is used as a binder in DE 100 62 672 A1.
  • Formulations for pouring slurries based on solvent mixtures without aromatics, such as toluene or xylene, and without chlorinated hydrocarbons, such as trichlorethylene, have so far not been known, especially in combination with lead-containing powders (e.g. PZT).
  • the method according to the invention for the production of ceramic green foils has the advantage over the prior art that ceramic multilayer components can be debindered in a substantially more time-saving manner, at lower temperatures and thus in a significantly more economical manner.
  • a further advantage lies in the fact that ceramic multilayer components with copper internal electrodes built up with the ceramic green foils produced according to the invention can be debindered in air.
  • Acrylate methacrylate copolymers for the production of ceramic green films for ceramic Multi-layer components, in particular for piezo multilayer actuators, are presented, which enable time-saving, simple and complete thermal debinding of green, ceramic multilayer components, the maximum debinding temperature not exceeding 35O 0 C.
  • the complete degradation of the binder is completed at these temperatures. This is due to the catalyzing effect of the PZT surface on the acrylate binder.
  • a residual carbon content is obtained which is less than 100 pppm.
  • the degradation mechanism is predominantly depolymerization.
  • the structure of the carbon chain (“backbone”) is attacked, so that mainly monomers are formed and discharged. Pyrolysis carbon is hardly formed.
  • the recipe according to the invention also allows ceramic multilayer components with oxidation-prone but inexpensive inner electrode materials, such as copper, to be quickly and correctly debound in air instead of in a low-oxygen atmosphere, without an unacceptable oxidation of the electrode layers occurring.
  • the thermal decomposition of the polymer takes place primarily by depolymerization, which leads to the formation of volatile monomers, while when PVB-based systems used previously are degraded, the side groups are first split off and the remaining carbon chain (“backbone”) only at higher levels Temperatures is decomposed oxidatively.
  • the low residual carbon content of less than 100 ppm achieved when using the recipe according to the invention is particularly important because carbon acts as a reducing agent for PbO in PZT-based ceramics. Together with copper, lead forms a low-melting alloy and can, for example in the case of PZT actuators with copper-containing internal electrodes, melt the electrodes and thus destroy the component.
  • the ceramic green sheets according to the invention for ceramic multilayer components are obtained by using a novel formulation of a casting slip, the method comprising the following steps: 1) Prepare a dispersant solution
  • the dispersant solution is prepared by weighing and homogenizing dispersants and a solvent mixture in a proportion of approximately 50% by weight, based on the total solvent proportion of the slip.
  • Dispersants with acid groups which have a sufficient dispersing action without aromatic hydrocarbons, i.e. without non-polar solvent components, have proven to be advantageous as dispersants.
  • Such dispersants are known from the paint industry, for example as Disperbyk 102, 110, 111, 140, 142 and 180 (BYK-Chemie).
  • oxa acids such as 3,6-dioxaheptanoic acid, 3,6,9-trioxadecanoic acid, 3,6,9-trioxaundecanedioic acid or polyglycol diacids, in combination with the above-mentioned complex dispersants is necessary in order to achieve an optimal dispersing effect to achieve.
  • the amounts added depend on the BET surface area of the PZT powder used (the higher the BET surface area, the higher the proportion of
  • Oxa acid ranges from 0.5 - 2.0% by weight of active ingredient, based on the PZT powder.
  • the binder solution is preferably prepared in a ratio of 70:20:10 by weighing and homogenizing the solvent mixture, binder and plasticizer.
  • the proportion of solvent is in the range of 60-80% by weight
  • the ratio between binder and plasticizer is in the range of 55:45 to 75:25% by weight.
  • acrylate methacrylate copolymers such as, for example, are used as binders
  • Paraloid B-72 (Rohm & Haas), Elvacite 2014, 2042, 2043, 4021 (Lucite International) are used, which have the advantages mentioned above (debinding temperature ⁇ 35O 0 C, residual carbon content ⁇ 100 ppm).
  • Ester-based, phthalate-free plasticizers are preferably used as plasticizers, since these have a favorable degradation behavior or a favorable influence on the thermal debinding behavior of the ceramic multilayer components.
  • phthalate-free plasticizers are harmless to health.
  • Esters of citric and adipic acid for example tributlycitrate, triethylcitrate, acetyltributylcitrate, bis-2-ethylhexyl adipate and isononyl adipate, have proven to be particularly advantageous.
  • a ceramic powder in particular a PZT powder and the dispersant solution prepared in step 1 in a ratio of 70:30 to 90:10% by weight, depending on the concentration of the binder solution, preferably 85:15% by weight, homogenizing and Deagglomerating in a vibrating or an annular gap mill with ZrO 2 grinding media over a period of 0.1 to 10 hours, preferably 3 hours, a first dispersion (slip) is produced. 4) Preparation of the casting slip (second dispersion)
  • the first dispersion (pre-slip) produced in step 3 and the binder solution from step 2 are weighed out in a ratio of 70:30 to 90:10% by weight, preferably 80:20% by weight, homogenized and in a vibrating or a Annular gap mill with ZrO 2 grinding media deagglomerated over a period of 0.1 to 5 hours, preferably 1 hour.
  • step 4 With a vacuum pump, air and volatile solvent components are simultaneously removed from the casting slurry (second dispersion) prepared in step 4 and the viscosity for casting is adjusted on a conventional film casting installation, preferably using the known doctor blade method.
  • a stirred tank is evacuated by moving the slip with an agitator and tempering to room temperature.
  • the viscosity is set at a shear rate of 6.8 l / S to a value of 1500 to 4000 mPas ⁇ , preferably to 2000 mPas.
  • the advantage of the multi-layer components constructed with the green foils obtained by the above method lies above all in that, compared to the prior art, they can be debindered in a much more time-saving manner, at lower temperatures and thus much more economically.
  • Another advantage is that multi-layer components, in particular piezo multilayer actuators based on PZT, with inner electrodes that are more susceptible to oxidation but less expensive, for example made of passivated copper, because of the shorter debinding time and temperature, compared to precious metals (Pt, Ag, Pd and combinations thereof) Air can be released. So far, long (3 days and more), complicated, time-consuming and therefore expensive debinding processes under inert conditions (nitrogen and / or H 2 and / or H 2 O) have been required. The process effort is significantly lower due to the method according to the invention. Another advantage is that thermal debinding produces harmless degradation products that can be completely removed. This results in residual carbon contents of less than 100 ppm.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Composite Materials (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

The invention relates to a method for producing ceramic green films for ceramic components, in particular multi-layer ceramic components. According to said method, a dispersant solution is first produced by the homogenisation of a dispersant in a solvent mixture. A binding solution is then produced by the homogenisation of a solvent mixture with an acrylate-methacrylate copolymer and a softener. After the production of a first dispersion by the homogenisation of a ceramic powder and the dispersant solution and subsequent deagglomeration, a second dispersion is formed by the homogenisation of the first dispersion and the binding solution and by the subsequent removal of air and highly volatile solvent fractions from the second dispersion.

Description

Verfahren zur Herstellung von keramischen Grünfolien für keramische BauteileProcess for the production of ceramic green foils for ceramic components
Die Erfindung betrifft allgemein ein Verfahren zur Herstellung von Grünfolien für keramische Bauteile, insbesondere Mehrlagenbauteile nach dem Oberbegriff des Anspruchs 1.The invention relates generally to a method for producing green films for ceramic components, in particular multi-layer components according to the preamble of claim 1.
Stand der TechnikState of the art
Ein Schwerpunkt in der keramischen Produktionstechnologie liegt in der Entwicklung neuer Verfahren zur Grünlingsherstellung. Beispiele hierfür sind der keramische Spritzguß, das Gel- Casting oder die Near-Net Shape Technologie. Alle Prozesse erfordern den Einsatz großer Mengen organischer Hilfsmittel, wie z.B. Binder, Gleitmittel oder Stabilisatoren, die vor oder während des Sinterprozesses aus den Grünteilen entfernt werden müssen. DieserOne focus in ceramic production technology is the development of new green body manufacturing processes. Examples of this are ceramic injection molding, gel casting or near-net shape technology. All processes require the use of large quantities of organic aids, e.g. Binders, lubricants or stabilizers that have to be removed from the green parts before or during the sintering process. This
Entbinderungsprozess ist zum einen zeit- und kostenintensiv, zum anderen bedingt er Umweltbelastungen durch die entstehenden, zum Teil gesundheitsschädlichen Abbauprodukte.The debinding process is on the one hand time and cost intensive, on the other hand it causes environmental pollution from the resulting, partly harmful degradation products.
Bindersysteme für keramische Grünfolien auf Basis von Polyacrylaten und -methacrylaten sind bekannt und werden beispielsweise in der Kondensatorindustrie verwendet. Üblicherweise werden hierbei wässrige Dispersionen von Polyacrylaten für die sehr dünnen Kondensatorfolien (2 - 20 μm) verwendet. Bei Schichtdicken ab etwa 100 μm sind wässrige Systeme wegen der langen Trocknungszeiten nicht mehr wirtschaftlich. Soweit hier Rezepturen mit Acrylatharzen zum Einsatz kommen, leiten sie sich von Polyvinylbutyral (PVB)-Rezepturen ab und es werden die entsprechenden bekannten Dispergatoren wie zum Beispiel Fischöl oder Phosphorsäureester, und Lösungsmittelmischungen wie Ethanol/Toluol eingesetzt.Binder systems for ceramic green sheets based on polyacrylates and methacrylates are known and are used, for example, in the capacitor industry. Aqueous dispersions of polyacrylates are usually used for the very thin capacitor foils (2 - 20 μm). With layer thicknesses from around 100 μm, aqueous systems are no longer economical due to the long drying times. As far as formulations with acrylate resins are used, they are derived from polyvinyl butyral (PVB) formulations and the corresponding known dispersants such as fish oil or phosphoric acid esters and solvent mixtures such as ethanol / toluene are used.
Keramische, insbesondere piezokeramische Bauelemente umfassen mehrere, insbesondere viele Schichten (Vielschicht- oder Mehrlagenbauelemente), sie sind beispielsweise als Aktoren in Piezostapeln (Piezostacks) nutzbar, indem durch Spannungsansteuerung eine trägheitsarme mechanische Auslenkung vergleichsweise hoher Kraft erreicht wird, oder als Biegeelement einsetzbar, indem die Spannungsansteuerung eine hohe mechanische Auslenkung geringerer Kraft hervorruft, oder sie gestatten die Erzeugung hoher elektrischer Spannungen beziehungsweise dienen in entsprechenden Vorrichtungen der Detektion mechanischer oder der Erzeugung akustischer Schwingungen.Ceramic, in particular piezoceramic components comprise several, in particular many layers (multi-layer or multi-layer components), they are for example as Actuators in piezo stacks (piezo stacks) can be used by achieving a low-inertia mechanical deflection of comparatively high force by means of voltage control, or can be used as a bending element by the voltage control causing a high mechanical deflection of less force, or they allow the generation of high electrical voltages or serve in corresponding devices the detection of mechanical or the generation of acoustic vibrations.
Bisherige technische Lösungen basieren vorwiegend auf Keramikmassen vom Strukturtyp der Perowskite der allgemeinen Formel ABO3, wobei die piezoelektrischen Eigenschaften im ferroelektrischen Zustand zum Tragen kommen. Als besonders vorteilhaft haben sich durch bestimmte Zusätze modifizierte Bleizirkonattitanat-Keramiken, Pb(Zr1-XTix)O3 (PZT), erwiesen. Zwischen den nach typischen Verfahren der Keramik-Folientechnologie hergestellten Keramikschichten befinden sich mittels Siebdruck aufgebrachte Edelmetall- Innenelektroden. Die Edelmetallelektroden gestatten, die im Prozess der Keramikfolienherstellung angewandten Dispergatoren und Binder sowie die weiteren organischen Additive und ebenso die organischen Bestandteile der Siebdruck-Metallpaste aus den Vielschichtstapeln an der Luft durch Depolymeristion und Oxidation thermisch zu eliminieren, so dass anschließend eine Sinterverdichtung bei ca. 1100 bis 115O0C ermöglicht wird, ohne dass Reduktionseffekte, etwa bedingt durch verbliebene Kohlenstoffreste, wirksam werden, die die Eigenschaften der Keramik infolge von Reduktionsreaktionen negativ beeinflussen.Previous technical solutions have been based predominantly on ceramic masses of the structure type of the perovskite of the general formula ABO 3 , the piezoelectric properties having an effect in the ferroelectric state. Lead zirconate titanate ceramics modified with certain additives, Pb (Zr 1-X Ti x ) O 3 (PZT), have proven to be particularly advantageous. Between the ceramic layers produced according to the typical processes of ceramic film technology, there are precious metal internal electrodes applied by means of screen printing. The noble metal electrodes allow the dispersants and binders used in the process of producing ceramic foils as well as the other organic additives and also the organic components of the screen printing metal paste to be thermally eliminated from the multilayer stacks in the air by depolymerization and oxidation, so that a sinter compaction at approx. 1100 up to 115O 0 C is made possible without reducing effects, for example due to remaining carbon residues, which have a negative effect on the properties of the ceramic as a result of reduction reactions.
Die DE 100 62 672 Al beschreibt piezoelektrische Bauelemente in monolithischer Vielschichtbauweise mit einem Stapel aus mindestens zwei Keramikschichten und einer zwischen zwei Keramikschichten angeordneten Elektrodenschicht, bei dem die Elektrodenschicht Kupfer enthält. Mit diesen kupferhaltigen Innenelektroden gelingt eine praktisch vollständige Entbinderung vor dem Einsetzen der Sinterverdichtung unter Inertbedingungen dadurch, dass man der Inertatmosphäre bei der Entbinderung reichlich Wasserdampf zuführt und nur einen bestimmtemn Sauerstoffpartialdruck zulässt, der die kupferhaltigen Innenelektroden unversehrt lässt. Dadurch werden die Voraussetzungen geschaffen, dass im Prozess der anschließenden Sinterverdichtung Piezoaktoren mit optimalen Eigenschaftswerten der Keramik erhalten werden, die denen einer unter analogen Bedingungen getrennt von der kupferhaltigen Elektrodenschicht oder auch an der Luft gesinterten Piezokeramikschicht der betreffenden Zusammensetzung nicht nachstehen bzw. diese sogar noch übertreffen. Als Binder wird in der DE 100 62 672 Al eine Polyurethandispersion verwendet.DE 100 62 672 A1 describes piezoelectric components in a monolithic multilayer construction with a stack of at least two ceramic layers and an electrode layer arranged between two ceramic layers, in which the electrode layer contains copper. With these copper-containing internal electrodes, virtually complete debinding is achieved before the onset of sintering compression under inert conditions by supplying the inert atmosphere with a large amount of water vapor during the debinding and allowing only a certain partial pressure of oxygen, which leaves the copper-containing internal electrodes intact. This creates the prerequisites that in the process of subsequent sinter compaction, piezo actuators with optimal properties of the ceramic are obtained, which are similar to those of one Conditions separate from the copper-containing electrode layer or even air-sintered piezoceramic layer are not inferior to or even exceed the composition in question. A polyurethane dispersion is used as a binder in DE 100 62 672 A1.
Rezepturen für Gießschlicker basierend auf Lösungsmittelmischungen ohne Aromaten, wie zum Beispiel Toluol oder Xylol, und ohne chlorierte Kohlenwasserstoffe, wie zum Beispiel Trichlorethylen, sind insbesondere in Kombination mit bleihaltigen Pulvern (z.B. PZT) bisher nicht bekannt.Formulations for pouring slurries based on solvent mixtures without aromatics, such as toluene or xylene, and without chlorinated hydrocarbons, such as trichlorethylene, have so far not been known, especially in combination with lead-containing powders (e.g. PZT).
Vorteile der ErfindungAdvantages of the invention
Das erfindungsgemäße Verfahren zur Herstellung von keramischen Grünfolien hat gegenüber dem Stand der Technik den Vorteil, dass sich keramische Mehrlagenbauelemente wesentlich zeitsparender, bei geringeren Temperaturen und somit wesentlich kostengünstiger entbindern lassen.The method according to the invention for the production of ceramic green foils has the advantage over the prior art that ceramic multilayer components can be debindered in a substantially more time-saving manner, at lower temperatures and thus in a significantly more economical manner.
Ein weiterer Vorteil liegt darin, dass mit den erfindungsgemäß hergestellten keramischen Grünfolien aufgebaute keramische Mehrlagenbauelemente mit Kupfer-Innenelektroden in Luft entbindert werden können.A further advantage lies in the fact that ceramic multilayer components with copper internal electrodes built up with the ceramic green foils produced according to the invention can be debindered in air.
Weiterhin ist vorteilhaft, dass der Austrag der beim thermischen Entbindern entstehenden Abbauprodukte schädigungsfrei und vollständig erfolgen kann.It is furthermore advantageous that the degradation products formed during thermal debinding can be discharged completely and without damage.
Vorteilhafte Weiterbildungen der Erfindung ergeben sich aus den in den Unteransprüchen genannten Maßnahmen.Advantageous developments of the invention result from the measures mentioned in the subclaims.
Ausführungsbeispieleembodiments
Es wird eine verbesserte Rezeptur für einen Gießschlicker auf der Basis vonIt will be an improved formulation for a pouring slurry based on
Acrylatmethacrylatcopolymeren zur Herstellung keramischer Grünfolien für keramische Mehrlagenbauteile, insbesondere für Piezovielschichtaktoren, vorgestellt, die ein zeitsparendes, einfaches und vollständiges thermisches Entbindern von grünen, keramischen Mehrlagenbauteilen ermöglicht, wobei die maximale Entbinderungstemperatur 35O0C nicht übersteigt. In Verbindung mit der PZT-Keramik ist der vollständige Abbau des Binders bei diesen Temperaturen abgeschlossen. Dies liegt an der katalysierenden Wirkung der PZT- Oberfläche auf dem Acrylat-Binder. Dabei wird ein Restkohlenstoffgehalt erhalten, der weniger als 100 pppm beträgt. Der Abbaumechanismus ist überwiegend eine Depolymerisation. Dabei wird die Struktur der Kohlenstoffkette („backbone") angegriffen, so dass hauptsächlich Monomere gebildet und ausgetragen werden. Es kommt dabei kaum zur Bildung von Pyrolyse-Kohlenstoff.Acrylate methacrylate copolymers for the production of ceramic green films for ceramic Multi-layer components, in particular for piezo multilayer actuators, are presented, which enable time-saving, simple and complete thermal debinding of green, ceramic multilayer components, the maximum debinding temperature not exceeding 35O 0 C. In connection with the PZT ceramic, the complete degradation of the binder is completed at these temperatures. This is due to the catalyzing effect of the PZT surface on the acrylate binder. A residual carbon content is obtained which is less than 100 pppm. The degradation mechanism is predominantly depolymerization. The structure of the carbon chain (“backbone”) is attacked, so that mainly monomers are formed and discharged. Pyrolysis carbon is hardly formed.
Die erfindungsgemäße Rezeptur erlaubt weiterhin, keramische Mehrlagenbauteile mit oxidationsanfalligen, aber kostengünstigen Innenelektrodenmaterialien, wie zum Beispiel Kupfer, in Luft statt in sauerstoffarmer Atmosphäre schnell und fehlerfrei zu entbindern, ohne dass eine inakzeptable Oxidation der Elektrodenschichten auftritt.The recipe according to the invention also allows ceramic multilayer components with oxidation-prone but inexpensive inner electrode materials, such as copper, to be quickly and correctly debound in air instead of in a low-oxygen atmosphere, without an unacceptable oxidation of the electrode layers occurring.
Bei den verwendeten Bindersystemen erfolgt die thermische Zersetzung des Polymers in erster Linie durch Depolymerisation, was zur Bildung von leichtflüchtigen Monomeren führt, während beim Abbau von bisher verwendeten PVB-basierten Systemen zunächst die Seitengruppen abgespalten und die zurückbleibende Kohlenstoffkette („backbone") erst bei höheren Temperaturen oxidativ zersetzt wird.In the binder systems used, the thermal decomposition of the polymer takes place primarily by depolymerization, which leads to the formation of volatile monomers, while when PVB-based systems used previously are degraded, the side groups are first split off and the remaining carbon chain (“backbone”) only at higher levels Temperatures is decomposed oxidatively.
Der bei Verwendung der erfindungsgemäßen Rezeptur erzielte niedrige Restkohlenstoffgehalt von weniger als 100 ppm ist deshalb besonders wichtig, weil Kohlenstoff bei PZT-basierten Keramiken als Reduktionsmittel für PbO wirkt. Zusammen mit Kupfer bildet Blei eine niedrig schmelzende Legierung und kann beispielsweise bei PZT- Aktoren mit kupferhaltigen Innenelektroden zum Aufschmelzen der Elektroden und somit zur Zerstörung des Bauteils führen.The low residual carbon content of less than 100 ppm achieved when using the recipe according to the invention is particularly important because carbon acts as a reducing agent for PbO in PZT-based ceramics. Together with copper, lead forms a low-melting alloy and can, for example in the case of PZT actuators with copper-containing internal electrodes, melt the electrodes and thus destroy the component.
Die erfmdungsgemäßen keramischen Grünfolien für keramische Mehrlagenbauteile werden durch die Verwendung einer neuartigen Rezeptur eines Gießschlickers erhalten, wobei das Verfahren folgende Schritte aufweist: 1) Herstellen einer DispergatorlösungThe ceramic green sheets according to the invention for ceramic multilayer components are obtained by using a novel formulation of a casting slip, the method comprising the following steps: 1) Prepare a dispersant solution
Die Dispergatorlösung wird durch Einwiegen und Homogenisieren von Dispergatoren und eines Lösungsmittelgemisches mit einem Anteil von ungefähr 50% Gew.-%, bezogen auf den Gesamtlösungsmittelanteil des Schlickers, hergestellt.The dispersant solution is prepared by weighing and homogenizing dispersants and a solvent mixture in a proportion of approximately 50% by weight, based on the total solvent proportion of the slip.
Als Dispergatoren haben sich polymere Dispergatoren mit Säuregruppen als vorteilhaft herausgestellt, die ohne aromatische Kohlenwasserstoffe, d.h., ohne unpolare Lösungsmittelanteile eine ausreichende dispergierende Wirkung entfalten. Solche Dispergatoren sind aus der Lackindustrie bekannt, beispielsweise als Disperbyk 102, 110, 111, 140, 142 und 180 (Fa. BYK-Chemie). Die Verwendung von organischen Säuren, vorzugsweise sogenannter Oxasäuren, wie beispielsweise 3,6-Dioxaheptansäure, 3,6,9- Trioxadecansäure, 3,6,9-Trioxaundecandisäure oder Polyglycoldisäuren in Kombination mit den oben genannten komplexen Dispergatoren ist notwendig, um eine optimale Dispergierwirkung zu erzielen. Die Zugabemengen sind abhängig von der BET-Oberfläche des verwendeten PZT-Pulvers (je höher die BET-Oberfläche, desto höher der Anteil anPolymeric dispersants with acid groups which have a sufficient dispersing action without aromatic hydrocarbons, i.e. without non-polar solvent components, have proven to be advantageous as dispersants. Such dispersants are known from the paint industry, for example as Disperbyk 102, 110, 111, 140, 142 and 180 (BYK-Chemie). The use of organic acids, preferably so-called oxa acids, such as 3,6-dioxaheptanoic acid, 3,6,9-trioxadecanoic acid, 3,6,9-trioxaundecanedioic acid or polyglycol diacids, in combination with the above-mentioned complex dispersants is necessary in order to achieve an optimal dispersing effect to achieve. The amounts added depend on the BET surface area of the PZT powder used (the higher the BET surface area, the higher the proportion of
Oxasäure) und bewegen sich im Bereich von 0,5 - 2,0% Gew.-% Wirkstoff, bezogen auf das PZT-Pulver.Oxa acid) and range from 0.5 - 2.0% by weight of active ingredient, based on the PZT powder.
Der mit der Verwendung der o.g. Dispergatoren einhergehende Verzicht auf aromatische Kohlenwasserstoffe als Lösungsmittel ist ein entscheidender Vorteil des erfindungsgemäßen Verfahrens, da diese Substanzen gesundheitsschädlich und somit kennzeichnungspflichtig sind.With the use of the above Dispensing with aromatic hydrocarbons as solvents is a decisive advantage of the process according to the invention, since these substances are harmful to health and therefore require labeling.
Als Lösungsmittel haben sich Mischungen aus niederen Alkoholen, Estern und Ketonen, zum Beispiel Ethanol, Isopropanol, n-Propanol, n-Butanol, Ethylacetat, Butylacetat, l-Methoxy-2- propylacetat, Methylethylketon, als vorteilhaft herausgestellt, die in ihrer Flüchtigkeit und ihren Anteilen so aufeinander abgestimmt sind, dass sie während des Gießprozesses bei der Trocknung nacheinander schonend ausgetrieben werden können. Ein Beispiel einer solchen Mischung ist die Mischung Ethanol:Butylacetat:Butanol im Verhältnis (Gew.-%) 40:30:30. Andere Mischungen sind jedoch ebenfalls möglich. Der Anteil an Alkoholen ist wegen der Unterstützung der Dispergatorwirkung und der günstigen Beeinflussung des Fließverhaltens des Schlickers unverzichtbar. Es hat sich als vorteilhaft erwiesen, wenn mindestens ein Alkohol in der Mischung enthalten ist.Mixtures of lower alcohols, esters and ketones, for example ethanol, isopropanol, n-propanol, n-butanol, ethyl acetate, butyl acetate, l-methoxy-2-propyl acetate, methyl ethyl ketone, have been found to be advantageous as solvents, which in their volatility and their proportions are coordinated so that they can be gently driven out one after the other during the casting process during drying. An example of such a mixture is the mixture ethanol: butyl acetate: butanol in the ratio (% by weight) 40:30:30. However, other mixtures are also possible. The proportion of alcohols is due to the support of the dispersant effect and the favorable influence on the flow behavior of the slip indispensable. It has proven to be advantageous if the mixture contains at least one alcohol.
2) Herstellen einer Binderlösung2) Prepare a binder solution
Die Binderlösung wird durch Einwiegen und Homogenisieren von Lösungsmittelgemisch, Binder und Weichmacher vorzugsweise im Verhältnis 70:20:10 hergestellt. Allgemein liegt der Anteil an Lösungsmittel im Bereich von 60-80 Gew.-%, und das Verhältnis zwischen Binder und Weichmacher liegt im Bereich von 55:45 bis 75:25 Gew.-%.The binder solution is preferably prepared in a ratio of 70:20:10 by weighing and homogenizing the solvent mixture, binder and plasticizer. In general, the proportion of solvent is in the range of 60-80% by weight, and the ratio between binder and plasticizer is in the range of 55:45 to 75:25% by weight.
Als Binder werden erfindungsgemäß Acrylatmethacrylatcopolymere, wie zum BeispielAccording to the invention, acrylate methacrylate copolymers such as, for example, are used as binders
Paraloid B-72 (Fa. Rohm & Haas), Elvacite 2014, 2042, 2043, 4021 (Fa. Lucite International) verwendet, die die o.g. Vorteile (Entbinderungstemperatur < 35O0C, Restkohlenstoffgehalt < 100 ppm) aufweisen.Paraloid B-72 (Rohm & Haas), Elvacite 2014, 2042, 2043, 4021 (Lucite International) are used, which have the advantages mentioned above (debinding temperature <35O 0 C, residual carbon content <100 ppm).
Als Weichmacher werden bevorzugt esterbasierte, phthalatfreie Weichmacher eingesetzt, da diese ein günstiges Abbauverhalten beziehungsweise einen günstigen Einfluss auf das thermische Entbinderungsverhalten der keramischen Mehrlagenbauteile ausüben. Darüber hinaus sind phthalatfreie Weichmacher gesundheitlich unbedenklich. Als besonders vorteilhaft haben sich Ester der Zitronen- und Adipinsäure, beispielsweise Tributlycitrat, Triethylcitrat, Acetyltributylcitrat, Bis-2-Ethylhexyladipat und Isononyladipat erwiesen.Ester-based, phthalate-free plasticizers are preferably used as plasticizers, since these have a favorable degradation behavior or a favorable influence on the thermal debinding behavior of the ceramic multilayer components. In addition, phthalate-free plasticizers are harmless to health. Esters of citric and adipic acid, for example tributlycitrate, triethylcitrate, acetyltributylcitrate, bis-2-ethylhexyl adipate and isononyl adipate, have proven to be particularly advantageous.
3) Herstellen eines Vorschlickers (erste Dispersion)3) Preparation of a slip (first dispersion)
Durch Einwiegen eines keramischen Pulvers, insbesondere eines PZT-Pulvers und der in Schritt 1 hergestellten Dispergatorlösung im Verhältnis 70:30 bis 90:10 Gew.-%, abhängig von der Konzentration der Binderlösung, vorzugsweise 85:15 Gew.-%, Homogenisieren und Deagglomerieren in einer Schwing- oder einer Ringspaltmühle mit Zrθ2-Mahlkörpern über eine Zeitdauer von 0, 1 bis 10 Stunden, vorzugsweise 3 Stunden, wird eine erste Dispersion (Vorschlicker) hergestellt. 4) Herstellen des Gießschlickers (zweite Dispersion)By weighing a ceramic powder, in particular a PZT powder and the dispersant solution prepared in step 1 in a ratio of 70:30 to 90:10% by weight, depending on the concentration of the binder solution, preferably 85:15% by weight, homogenizing and Deagglomerating in a vibrating or an annular gap mill with ZrO 2 grinding media over a period of 0.1 to 10 hours, preferably 3 hours, a first dispersion (slip) is produced. 4) Preparation of the casting slip (second dispersion)
Die in Schritt 3 hergestellte erste Dispersion (Vorschlicker) und die Binderlösung aus Schritt 2 werden im Verhältnis von 70:30 bis 90:10 Gew.-%, vorzugsweise 80:20 Gew.-% eingewogen, homogenisiert und in einer Schwing- oder einer Ringspaltmühle mit ZrO2- Mahlkörpern über eine Zeitdauer von 0,1 bis 5 Stunden, vorzugsweise 1 Stunde deagglomeriert.The first dispersion (pre-slip) produced in step 3 and the binder solution from step 2 are weighed out in a ratio of 70:30 to 90:10% by weight, preferably 80:20% by weight, homogenized and in a vibrating or a Annular gap mill with ZrO 2 grinding media deagglomerated over a period of 0.1 to 5 hours, preferably 1 hour.
5) Fertigstellen des Gießschlickers (zweite Dispersion) und Einstellen der Rheologie5) Finishing the pouring slip (second dispersion) and adjusting the rheology
Mit einer Vakuumpumpe werden aus dem in Schritt 4 hergestellten Gießschlicker (zweite Dispersion) Luft und leichtflüchtige Lösungsmittelanteile gleichzeitig entfernt und die Viskosität für das Gießen auf einer konventionellen Foliengießanlage, vorzugsweise nach dem bekannten Doctor-Blade-Verfahren, eingestellt. Dabei wird ein Rührbehälter evakuiert unter Bewegen des Schlickers mit einem Rührwerk und Temperieren auf Raumtemperatur. Die Viskosität wird bei einer Scherrate von 6,8 l/S auf einen Wert von 1500 bis 4000 mPas < eingestellt, vorzugsweise auf 2000 mPas.With a vacuum pump, air and volatile solvent components are simultaneously removed from the casting slurry (second dispersion) prepared in step 4 and the viscosity for casting is adjusted on a conventional film casting installation, preferably using the known doctor blade method. A stirred tank is evacuated by moving the slip with an agitator and tempering to room temperature. The viscosity is set at a shear rate of 6.8 l / S to a value of 1500 to 4000 mPas <, preferably to 2000 mPas.
Der Vorteil der mit den nach dem obigen Verfahren erhaltenen Grünfolien aufgebauten Mehrlagenbauteile liegt vor allem darin, dass sie sich im Vergleich zum Stand der Technik wesentlich zeitsparender, bei geringeren Temperaturen und somit wesentlich kostengünstiger entbindern lassen.The advantage of the multi-layer components constructed with the green foils obtained by the above method lies above all in that, compared to the prior art, they can be debindered in a much more time-saving manner, at lower temperatures and thus much more economically.
Ein weiterer Vorteil liegt darin, dass Mehrlagenbauteile, insbesondere Piezovielschichtaktoren auf PZT-Basis, mit im Vergleich zu Edelmetallen (Pt, Ag, Pd und Kombinationen daraus) oxidationsanfälligeren, aber kostengünstigeren Innenelektroden, biespielsweise aus passiviertem Kupfer, wegen der geringeren Entbinderungsdauer und — temperatur in Luft entbindert werden können. Bisher sind hier lange (3 Tage und mehr), komplizierte, regelaufwendige und somit teure Entbinderungsprozesse unter Inertbedingungen (Stickstoff und/oder H2 und/oder H2O) erforderlich. Der Prozessaufwand wird aufgrund des erfindungsgemäßen Verfahrens wesentlich geringer. Noch ein weiterer Vorteil besteht darin, dass beim thermischen Entbindern unschädliche Abbauprodukte entstehen, die vollständig ausgetragen werden können. Es resultieren damit Restkohlenstoffgehalte von weniger als 100 ppm. Another advantage is that multi-layer components, in particular piezo multilayer actuators based on PZT, with inner electrodes that are more susceptible to oxidation but less expensive, for example made of passivated copper, because of the shorter debinding time and temperature, compared to precious metals (Pt, Ag, Pd and combinations thereof) Air can be released. So far, long (3 days and more), complicated, time-consuming and therefore expensive debinding processes under inert conditions (nitrogen and / or H 2 and / or H 2 O) have been required. The process effort is significantly lower due to the method according to the invention. Another advantage is that thermal debinding produces harmless degradation products that can be completely removed. This results in residual carbon contents of less than 100 ppm.

Claims

Ansprüche Expectations
1. Verfahren zur Herstellung von keramischen Grünfolien für keramische Bauteile, insbesondere Mehrlagenbauteile, gekennzeichnet durch die Schritte:1. Process for the production of ceramic green foils for ceramic components, in particular multi-layer components, characterized by the steps:
a) Herstellen einer Dispergatorlösung durch Homogenisieren eines oder mehrerer Dispergatoren in Kombination mit einer organischen Säure in einem Lösungsmittelgemisch; b) Herstellen einer Binderlösung durch Homogenisieren des Lösungsmittelgemisches aus Schritt a), einem oder mehrerena) preparing a dispersant solution by homogenizing one or more dispersants in combination with an organic acid in a solvent mixture; b) preparing a binder solution by homogenizing the solvent mixture from step a), one or more
Acrylatmethacrylatcopolymeren als Binder und einem oder mehreren Weichmachern; c) Herstellen einer ersten Dispersion durch Homogenisieren eines keramischen Pulvers und der Dispergatorlösung und anschließendes Deagglomerieren; d) Herstellen einer zweiten Dispersion durch Homogenisierung der ersten Dispersion und der Binderlösung; und e) Entfernen von Luft und leichtflüchtigen Lösungsmittelanteilen aus der zweiten Dispersion.Acrylate methacrylate copolymers as binders and one or more plasticizers; c) preparing a first dispersion by homogenizing a ceramic powder and the dispersant solution and then deagglomerating; d) preparing a second dispersion by homogenizing the first dispersion and the binder solution; and e) removing air and volatile solvent components from the second dispersion.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass als Dispergatoren polymere Dispergatoren mit Säuregruppen verwendet werden.2. The method according to claim 1, characterized in that polymeric dispersants with acid groups are used as dispersants.
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass als organische Säure Oxasäuren verwendet werden.3. The method according to claim 1 or 2, characterized in that oxa acids are used as organic acid.
4. Verfahren nach Anspruch 3, dadurch gekennzeichnet, dass die Oxasäuren ausgewählt sind aus der Gruppe bestehend aus 3,6-Dioxaheptansäure, 3,6,9-Trioxadecansäure, 3,6,9- Trioxaundecandisäure und Polyglycoldisäure.4. The method according to claim 3, characterized in that the oxa acids are selected from the group consisting of 3,6-dioxaheptanoic acid, 3,6,9-trioxadecanoic acid, 3,6,9- Trioxaundecanedioic acid and polyglycoledioic acid.
5. Verfaliren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass das Lösungsmittelgemisch ausgewählt ist aus der Gruppe bestehend aus Alkoholen, Estern und Ketonen, wobei das Lösungsmittelgemisch mindestens einen Alkohol enthält.5. Verfaliren according to any one of claims 1 to 4, characterized in that the solvent mixture is selected from the group consisting of alcohols, esters and ketones, wherein the solvent mixture contains at least one alcohol.
6. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass das Lösungsmittelgemisch ausgewählt ist aus der Gruppe bestehend aus Ethanol, Isopropanol, n-Propanol, n-Butanol, Ethylacetat, Butylacetat, l-Methoxy-2-propylacetat und Methylethylketon.6. The method according to claim 5, characterized in that the solvent mixture is selected from the group consisting of ethanol, isopropanol, n-propanol, n-butanol, ethyl acetate, butyl acetate, l-methoxy-2-propyl acetate and methyl ethyl ketone.
7. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass eine thermische Zersetzung des Binderpolymers durch Depolymerisation erfolgt.7. The method according to any one of the preceding claims, characterized in that the binder polymer is thermally decomposed by depolymerization.
8. Verfahren nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass der Weichmacher ein esterbasierter, phthalatfreier Weichmacher ist.8. The method according to any one of claims 1 to 7, characterized in that the plasticizer is an ester-based, phthalate-free plasticizer.
9. Verfahren nach Anspruch 8, dadurch gekennzeichnet, dass der Weichmacher ein Ester der Zitronen- oder Adipinsäure ist.9. The method according to claim 8, characterized in that the plasticizer is an ester of citric or adipic acid.
10. Verfahren nach Anspruch 8 oder 9, dadurch gekennzeichnet, dass der Weichmacher ausgewählt ist aus der Gruppe bestehend aus Tributlycitrat, Triethylcitrat, Acetyltributylcitrat,10. The method according to claim 8 or 9, characterized in that the plasticizer is selected from the group consisting of tributlycitrate, triethyl citrate, acetyltributyl citrate,
Bis-2-Ethylhexyladipat und Isononyladipat.Bis-2-ethylhexyl adipate and isononyl adipate.
11 Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass das keramische Pulver ein PZT-Pulver ist.11. The method according to any one of the preceding claims, characterized in that the ceramic powder is a PZT powder.
12. Verfahren nach Anspruch 10 oder 11, dadurch gekennzeichnet, dass das keramische Pulver und die Dispergatorlösung im Verhältnis zwischen 70:30 bis 90:10, vorzugsweise im Verhältnis 85:15 homogenisiert werden.12. The method according to claim 10 or 11, characterized in that the ceramic powder and the dispersant solution are homogenized in a ratio between 70:30 to 90:10, preferably in a ratio of 85:15.
13. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die erste Dispersion und die Binderlösung im Verhältnis zwischen 70:30 und 90:10, vorzugsweise im Verhältnis 80:20 homogenisiert werden.13. The method according to any one of the preceding claims, characterized in that the first dispersion and the binder solution in a ratio between 70:30 and 90:10, preferably be homogenized in a ratio of 80:20.
14. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass das Entfernen von Luft und leichtflüchtigen Lösungsmittelanteilen aus der zweiten Dispersion gleichzeitig mit Hilfe einer Vakuumpumpe erfolgt.14. The method according to any one of the preceding claims, characterized in that the removal of air and volatile solvent components from the second dispersion is carried out simultaneously with the aid of a vacuum pump.
15. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass das Verhältnis von Binder zu Weichmacher im Bereich von 55:45 und 75:25, vorzugsweise bei 67:33 liegt.15. The method according to any one of the preceding claims, characterized in that the ratio of binder to plasticizer is in the range of 55:45 and 75:25, preferably 67:33.
16. Verwendung der keramischen Grünfolien nach einem der Ansprüche 1 bis 15 zur Herstellung von Piezovielschichtaktoren. 16. Use of the ceramic green sheets according to one of claims 1 to 15 for the production of piezo multilayer actuators.
PCT/DE2004/000777 2003-06-10 2004-04-14 Method for producing ceramic green films for ceramic components WO2004110954A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US10/560,125 US7713896B2 (en) 2004-04-14 2004-04-14 Method for producing ceramic green compacts for ceramic components
JP2006515648A JP2006527154A (en) 2003-06-10 2004-04-14 Manufacturing method of ceramic green sheet for ceramic device
EP04727226A EP1633686A1 (en) 2003-06-10 2004-04-14 Method for producing ceramic green films for ceramic components

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10326040.4 2003-06-10
DE10326040A DE10326040A1 (en) 2003-06-10 2003-06-10 Process for the production of ceramic green foils for ceramic components

Publications (1)

Publication Number Publication Date
WO2004110954A1 true WO2004110954A1 (en) 2004-12-23

Family

ID=33482734

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE2004/000777 WO2004110954A1 (en) 2003-06-10 2004-04-14 Method for producing ceramic green films for ceramic components

Country Status (4)

Country Link
EP (1) EP1633686A1 (en)
JP (1) JP2006527154A (en)
DE (1) DE10326040A1 (en)
WO (1) WO2004110954A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1881024A1 (en) * 2006-07-18 2008-01-23 Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO Use of a plasticizer in an electroactive polymer composition
WO2010113628A1 (en) * 2009-03-31 2010-10-07 積水化学工業株式会社 Method for producing slurry composition
CN112142480B (en) * 2020-09-22 2022-06-21 中国振华(集团)新云电子元器件有限责任公司(国营第四三二六厂) Ceramic slurry of wet process multilayer chip ceramic dielectric capacitor and preparation method thereof
DE102022114964A1 (en) 2022-06-14 2023-12-14 Technische Universität Darmstadt Körperschaft des öffentlichen Rechts Method for producing a capacitor element with a dielectric ceramic film, slip for producing a dielectric ceramic film and capacitor element with a dielectric ceramic film

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0313412A1 (en) 1987-10-23 1989-04-26 Nippon Shokubai Co., Ltd. Ceramic green sheet
WO1994007808A1 (en) 1992-10-06 1994-04-14 Hoechst Aktiengesellschaft Aqueous casting compound for producing green ceramic films and ceramic mouldings produced therefrom
EP0601457A1 (en) 1992-12-05 1994-06-15 Hoechst Aktiengesellschaft Prepared mixture of inorganic powders with polymeric adjuvants and use
DE10062672A1 (en) 1999-12-16 2001-08-02 Epcos Ag Piezoelectric component used as an actuator in a piezo-stack consists of a stack of ceramic layers with a copper electrode layer between the ceramic layers
US20020019462A1 (en) 2000-06-29 2002-02-14 Murata Manufacturing Co., Ltd. Ceramic slurry composition and manufacturing method therefor
US6599463B2 (en) * 1999-12-13 2003-07-29 Murata Manufacturing Co., Ltd. Monolithic ceramic electronic component and production process therefor, and ceramic paste and production process therefor
FR2835828A1 (en) * 2002-02-08 2003-08-15 Ct De Transfert De Technologie METHOD AND COMPOSITION FOR THE MANUFACTURE OF CERAMIC PIECES BY STEREO-LITHOPHOTOGRAPHY AND DENTAL FIELD APPLICATION

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61146753A (en) * 1984-12-20 1986-07-04 株式会社東芝 Manufacture of circuit substrate green sheet
JPS62283858A (en) * 1986-05-30 1987-12-09 株式会社東芝 Organic binder for ceramic
JPH0826832A (en) * 1994-05-09 1996-01-30 Fuji Elelctrochem Co Ltd Production of slurry for ceramic green sheet
JPH09295870A (en) * 1996-04-26 1997-11-18 Fuji Elelctrochem Co Ltd Production of slurry for ceramic green sheet
JP3743588B2 (en) * 1997-03-17 2006-02-08 Ｔｄｋ株式会社 Dielectric material molding binder
JP3397753B2 (en) * 1999-09-30 2003-04-21 ティーディーケイ株式会社 Multilayer piezoelectric element and manufacturing method thereof

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0313412A1 (en) 1987-10-23 1989-04-26 Nippon Shokubai Co., Ltd. Ceramic green sheet
WO1994007808A1 (en) 1992-10-06 1994-04-14 Hoechst Aktiengesellschaft Aqueous casting compound for producing green ceramic films and ceramic mouldings produced therefrom
EP0601457A1 (en) 1992-12-05 1994-06-15 Hoechst Aktiengesellschaft Prepared mixture of inorganic powders with polymeric adjuvants and use
US6599463B2 (en) * 1999-12-13 2003-07-29 Murata Manufacturing Co., Ltd. Monolithic ceramic electronic component and production process therefor, and ceramic paste and production process therefor
DE10062672A1 (en) 1999-12-16 2001-08-02 Epcos Ag Piezoelectric component used as an actuator in a piezo-stack consists of a stack of ceramic layers with a copper electrode layer between the ceramic layers
US20020019462A1 (en) 2000-06-29 2002-02-14 Murata Manufacturing Co., Ltd. Ceramic slurry composition and manufacturing method therefor
FR2835828A1 (en) * 2002-02-08 2003-08-15 Ct De Transfert De Technologie METHOD AND COMPOSITION FOR THE MANUFACTURE OF CERAMIC PIECES BY STEREO-LITHOPHOTOGRAPHY AND DENTAL FIELD APPLICATION

Also Published As

Publication number Publication date
JP2006527154A (en) 2006-11-30
DE10326040A1 (en) 2004-12-30
EP1633686A1 (en) 2006-03-15

Similar Documents

Publication Publication Date Title
DE102007013874A1 (en) Multilayer piezoelectric element
EP2264800B1 (en) Multi-layered ceramic component
EP0716054A2 (en) Firing and sintering process for a ceramic, electronic component
DE102011117709A1 (en) Ceramic material, method for producing the same and electroceramic component comprising the ceramic material
EP1774603A1 (en) Multi-layered component and method for the production thereof
WO2004110954A1 (en) Method for producing ceramic green films for ceramic components
EP0750597B1 (en) Method of producing ceramic composite bodies
DE102006015042B4 (en) Lead-free piezoceramic material with copper doping, method for producing a piezoceramic component with the material and use of the component
WO2004110953A1 (en) Method for the production of pzt-based ceramics having a low sintering temperature
US7713896B2 (en) Method for producing ceramic green compacts for ceramic components
DE102005061528A1 (en) A piezoelectric composition containing: rare earth metal, alkali earth metal, Fe, W useful for fuel injection valves of internal combustion engines (claimed), piezoelectric transformers and motors and untrasonic transducers
DE68906981T2 (en) Composition for extruding a green body to be sintered.
DE102007028094B4 (en) Lead zirconate titanate ceramic with texturing, method for making the ceramic and a piezoceramic component and its use
EP3030537A1 (en) Piezoceramic material with reduced lead content
EP2147469A1 (en) Piezoelectric multi-layer component
DE102005061529B4 (en) Lead zirconate titanate with nickel-molybdenum doping, method for producing a piezoceramic component using the lead zirconate titanate and use of the piezoceramic component
EP0441219A1 (en) Slip for the production of green ceramic sheets and use thereof
DE19935271C2 (en) Matrix material for fuel cells, process for its production and its use
WO2017178239A1 (en) Paste-like composition and method for producing three-dimensional structures or structural elements on substrate surfaces
DE102019206018B4 (en) Electromechanical actuator with ceramic insulation, method for its production and method for controlling such an actuator
WO2002004379A2 (en) Sintered, electrically conductive material, ceramic multilayer component comprising this material, and method for the production thereof
DE102010029096B4 (en) Process for the production of a ceramic component
DE102015101311A1 (en) Method for producing piezoelectric multilayer components
DE102022114964A1 (en) Method for producing a capacitor element with a dielectric ceramic film, slip for producing a dielectric ceramic film and capacitor element with a dielectric ceramic film
DE102020107305A1 (en) Piezoelectric multilayer element

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

WWE Wipo information: entry into national phase

Ref document number: 2004727226

Country of ref document: EP

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 2006515648

Country of ref document: JP

WWP Wipo information: published in national office

Ref document number: 2004727226

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2006226569

Country of ref document: US

Ref document number: 10560125

Country of ref document: US

WWP Wipo information: published in national office

Ref document number: 10560125

Country of ref document: US