EP1968894A1 - Procede pour realiser un corindon colore de taille nanometrique - Google Patents

Procede pour realiser un corindon colore de taille nanometrique

Info

Publication number
EP1968894A1
EP1968894A1 EP06754655A EP06754655A EP1968894A1 EP 1968894 A1 EP1968894 A1 EP 1968894A1 EP 06754655 A EP06754655 A EP 06754655A EP 06754655 A EP06754655 A EP 06754655A EP 1968894 A1 EP1968894 A1 EP 1968894A1
Authority
EP
European Patent Office
Prior art keywords
agglomerates
coloring
grinding
carries out
oxide
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP06754655A
Other languages
German (de)
English (en)
Inventor
Norbert RÖSCH
Ernst Krendlinger
Peter Klug
Waltraud Simsch
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Clariant Finance BVI Ltd
Original Assignee
Clariant International Ltd
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
Priority claimed from DE102005033393.1A external-priority patent/DE102005033393B4/de
Priority claimed from DE102005039435A external-priority patent/DE102005039435A1/de
Priority claimed from DE102005039436A external-priority patent/DE102005039436B4/de
Priority claimed from DE102006012319A external-priority patent/DE102006012319A1/de
Priority claimed from DE200610020515 external-priority patent/DE102006020515B4/de
Priority claimed from DE200610020516 external-priority patent/DE102006020516A1/de
Priority claimed from DE102006021705A external-priority patent/DE102006021705B3/de
Application filed by Clariant International Ltd filed Critical Clariant International Ltd
Publication of EP1968894A1 publication Critical patent/EP1968894A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C01F7/30—Preparation of aluminium oxide or hydroxide by thermal decomposition or by hydrolysis or oxidation of aluminium compounds
    • C01F7/306—Thermal decomposition of hydrated chlorides, e.g. of aluminium trichloride hexahydrate
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • C01P2002/52—Solid solutions containing elements as dopants
    • C01P2002/54—Solid solutions containing elements as dopants one element only
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer

Definitions

  • Colored sintered corundum is already known from EP 524 519. These are alpha alumina, in whose matrix chromophoric oxides are incorporated. This colored sintered corundum is produced by the so-called SoI-GeI process with the addition of inorganic color bodies or colored pigments.
  • the primary crystallite size of the colored sintered corundum obtained by this process is given as 0.1 to 3 ⁇ m, preferably 0.1 to 1 ⁇ m.
  • the object of the present invention is to provide an alternative process for the preparation of colored nanocorundum; which also allows the production of such colored nanocorundum having a particle size of less than 0.1 microns.
  • the invention relates to a process for the preparation of colored nanocorundum, wherein an aqueous solution of aluminum chlorohydrate with crystallization seeds and a coloring oxide added, then dried, calcined within less than 30 minutes and comminuted the resulting agglomerates.
  • the starting point for the process according to the invention is aluminum chlorohydrate, which has the formula Al 2 (OH) x Cl y, where x is a number from 2.5 to 5.5 and y is a number from 3.5 to 0.5 and the sum of x and y is always 6.
  • This aluminum chlorohydrate is mixed as an aqueous solution with crystallization nuclei and one or more precursors of coloring metal oxides, then dried and then subjected to a thermal treatment (calcination).
  • the germs are very finely disperse corundum, diaspore or hematite.
  • Preference is given to taking very finely divided ⁇ -Al 2 O 3 nuclei having an average particle size of less than 0.1 ⁇ m. In general, 2 to 3 wt .-% of germs based on the resulting alumina from.
  • This starting solution additionally contains a coloring metal oxide or a compound which forms such a coloring metal oxide during calcination.
  • a coloring metal oxide for example, the oxides of chromium, vanadium, iron, nickel or cobalt are suitable.
  • the amount of coloring metal oxide is generally 0.1 to 30, preferably 0.1 to 20 wt .-%, based on the Al 2 O 3 matrix.
  • Particularly suitable precursors of chromophoric metal oxides are the chlorides, nitrates, sulfates, carbonates or the corresponding basic compounds of the salts mentioned.
  • This suspension of aluminum chlorohydrate, seeds and coloring metal oxide or metal oxide precursor is then evaporated to dryness and subjected to a thermal treatment (calcination).
  • This calcination is carried out in suitable devices, for example in push-through, chamber, tube, rotary kiln or microwave ovens or in a fluidized bed reactor.
  • suitable devices for example in push-through, chamber, tube, rotary kiln or microwave ovens or in a fluidized bed reactor.
  • the temperature for the calcination should not exceed 1100 0 C.
  • the lower temperature limit depends on the desired yield of colored nanocorundum, on the desired residual chlorine content and on the content of germs.
  • the corundum formation starts at about 500 0 C, but to keep the chlorine content low and the yield of colored nanocorner high, but you will work preferably at 700 to 1100 ° C, in particular at 1000 to 1100 0 C.
  • the time for the calcination is generally less than 30 minutes, preferably between 0.5 and 10, in particular between 0.5 and 5 minutes. Already after this short time, a sufficient yield of colored nanocorund can be achieved under the conditions given above for the preferred temperatures.
  • agglomerates of the colored nanocorundum accumulate in the form of nearly spherical primary crystallites, the term "nano-" meaning a particle size of generally from 1 to 100 nm.
  • These agglomerates are deagglomerated in a subsequent step, wherein all known in the ceramic deagglomeration can be used, since it is in the present case relatively easily destructible-wee agglomerates-
  • a wet or dry grinding the wet grinding preferably in an attritor or agitator ball mill, while the dry grinding is carried out in an air jet mill.
  • the nanoparticles aimed at as a product during grinding are extremely reactive, it is preferred to add additives before or during the grinding which prevent re-agglomeration of the nanoparticles. It is therefore particularly favorable to carry out the subsequent deagglomeration in the form of a wet grinding.
  • vibration mills, attritor mills, ball mills, stirred ball mills or similar devices are suitable.
  • the use of agitator ball mills has proven to be particularly advantageous.
  • the grinding time depends on the strength of the agglomerates and the desired fineness and is usually between 2 and 6 hours in the process according to the invention.
  • Wet grinding or deagglomeration is advantageously carried out in an aqueous medium, but it is also possible to use alcoholic or other organic solvents.
  • an aqueous suspension of nanocrystalline corundum having a d50 value of less than 80 nm is obtained.
  • the suspension obtained after wet grinding can be converted into a defined powder by spray drying, fluidized bed drying, granulation or freeze drying. Another possibility is to modify the surfaces of the colored nanocorundum and thus to obtain an adaptation to organic solvents and coating compositions.
  • nanoparticles For the inventive modification of the surface of these nanoparticles with coating agents such.
  • coating agents such as silanes or siloxanes there are two possibilities.
  • deagglomeration can be carried out in the presence of the coating agent, for example by adding the coating agent to the mill during milling.
  • a second possibility consists of first destroying the agglomerates of the nanoparticles and then treating the nanoparticles, preferably in the form of a suspension in a solvent, with the coating agent.
  • suitable solvents for deagglomeration are both water and conventional solvents, preferably those which are also used in the paint industry, for example C 1 -C 6 -alcohols, in particular methanol, ethanol or isopropanol, acetone, tetrahydrofuran, butyl acetate.
  • an inorganic or organic acid for example HCl, HNO3, formic acid or acetic acid, should be added to stabilize the resulting nanoparticles in the aqueous suspension.
  • the amount of acid may be 0.1 to 5 wt .-%, based on the mixed oxide.
  • aqueous suspension of the acid-modified nanoparticles is then preferably the grain fraction having a particle diameter of less than 20 nm separated by centrifugation.
  • the coating agent preferably a silane or siloxane
  • the nanoparticles thus treated precipitate are separated and dried to a powder, for example by freeze-drying.
  • Suitable coating agents are preferably silanes or siloxanes or mixtures thereof.
  • suitable coating agents are all substances which can bind physically to the surface of the mixed oxides (adsorption) or which can bond to form a chemical bond on the surface of the mixed oxide particles. Since the surface of the mixed oxide particles is hydrophilic and free hydroxy groups are available, suitable coating agents are alcohols, compounds having amino, hydroxyl, carbonyl, carboxyl or mercapto functions, silanes or siloxanes. Examples of such coating compositions are polyvinyl alcohol, mono-, di- and tricarboxylic acids, amino acids, amines, waxes, surfactants, hydroxycarboxylic acids, organosilanes and organosiloxanes.
  • Suitable silanes or siloxanes are compounds of the formulas
  • n is an integer with the meaning 1 ⁇ n ⁇ 1000, preferably 1 ⁇ n ⁇ 100
  • m is an integer 0 ⁇ m ⁇ 12 and p is an integer 0 ⁇ p ⁇ 60 and q is an integer 0 ⁇ q ⁇ 40 and r is an integer 2 ⁇ r ⁇ 10 and s is an integer 0 ⁇ s ⁇ 18 and
  • Y is a reactive group, for example ⁇ , ⁇ -ethylenically unsaturated groups, such as (meth) acryloyl, vinyl or allyl groups, amino, amido, ureido, hydroxyl, epoxy, isocyanato, mercapto, sulfonyl, Phosphonyl, trialkoxylsilyl, alkyldialkoxysilyl, dialkylmonoalkoxysilyl, anhydride and / or carboxyl groups, imido, imino, sulfite, sulfate, sulfonate, phosphine, phosphite, phosphate, phosphonate and
  • X is a t-functional oligomer with t an integer 2 ⁇ t ⁇ 8 and
  • the t-functional oligomer X is preferably a:
  • radicals of oligoethem are compounds of the type - (CaH2a-O) b-CaH2a- or O- (CaH2a-O) b-CaH2a-O with 2 ⁇ a ⁇ 12 and 1 ⁇ b ⁇ 60, z.
  • residues of oligoesters are compounds of the type -CbH2b- (C (CO) CaH2a- (CO) O-CbH2b-) c- or -O-CbH2b- (C (CO) CaH2a- (CO) O-)
  • R 1 methyl, phenyl, -C4F9; OCF2-CHF-CF3, -C6F13, -O-CF2-CHF2
  • silanes of the type defined above are, for. Hexamethyldisiloxane, octamethyltrisiloxane, other homologous and isomeric compounds of the series SinOn-1 (CH 3) 2n + 2, where n is an integer 2 ⁇ n ⁇ 1000, e.g. B. Polydimethylsiloxane 200® fluid (20 cSt).
  • Dihydrohexamethytrisiloxane, dihydrooctamethyltetrasiloxane other homologous and isomeric compounds of the series H - [(Si-O) n (CH 3) 2n] -Si (CH 3) 2 -H, where n is an integer 2 ⁇ n ⁇ 1000, preferably the ⁇ , ⁇ -dihydropolysiloxanes, e.g. B. polydimethylsiloxane (hydride end groups, Mn 580).
  • ⁇ -OH groups are also the corresponding difunctional compounds with epoxy, isocyanato, vinyl, AIIyI- and di (meth) acryloyl used, for.
  • R is an alkyl, such as. Methyl, ethyl, n-propyl, i-propyl, butyl,
  • R ' is an alkyl, such as. Methyl, ethyl, n-propyl, i-propyl, butyl,
  • R ' is a cycloalkyl n is an integer from 1 - 20 x + y 3 x 1 or 2 y 1 or 2
  • R is an alkyl, such as. As methyl, ethyl, propyl, m is a number between 0.1 - 20
  • R 1 is methyl, phenyl, -C 4 F 9; OCF2-CHF-CF3, -C6F13, -O-CF2-CHF2, -NH2,
  • R "" 1 H, alkyl
  • Preferred silanes are the silanes listed below: triethoxysilane, octadecyltimethoxysilane,
  • Tetramethoxysilanes Tetramethoxysilanes, tetraethoxysilanes, oligomeric tetraethoxysilanes (DYNASIL® 40 from Degussa), tetra-n-propoxysilanes,
  • 3-aminopropyltriethoxysilanes 3-aminopropyltrimethoxysilanes, 2-aminoethyl-3-aminopropyltrimethoxysilanes, triaminofunctional propyltrimethoxysilanes (DYNASYLAN® TRIAMINO from Degussa), N- (n-butyl-3-aminopropyltrimethoxysilanes, 3-aminopropylmethyldiethoxysilanes.
  • the coating compositions in particular the silanes or siloxanes, are preferably added in molar ratios of mixed oxide nanoparticles to silane of from 1: 1 to 10: 1.
  • the amount of solvent in the deagglomeration is generally 80 to 90 wt .-%, based on the total amount of mixed oxide nanoparticles and solvent.
  • the deagglomeration by grinding and simultaneous modification with the coating agent is preferably carried out at temperatures of 20 to 150 0 C, more preferably at 20 to 90 0 C.
  • the suspension is subsequently separated from the grinding beads.
  • the suspension can be heated to complete the reaction for up to 30 hours. Finally, the solvent is distilled off and the remaining residue is dried. It can also be advantageous to leave the modified mixed oxide nanoparticles in the solvent and to use the dispersion for other applications.
  • the dyed mixed oxide nanoparticles can be readily dispersed in non-aqueous systems.
  • the process according to the invention makes it possible to produce colored nanocorundum with very short reaction times, which is optionally surface-modified.
  • the colored, nanocrystalline, optionally surface-modified corundum produced in this way can be used in a variety of applications, for example as high-temperature stable pigment, for the production of ceramics and composites or abrasives or as an additive in paints and varnishes to improve scratch and abrasion resistance.
  • An X-ray structure analysis shows that predominantly ⁇ -alumina is present.
  • the images of the SEM image taken showed crystallites in the range 10 - 80 nm (estimate from SEM image), which are present as agglomerates.
  • the residual chlorine content was only a few ppm.
  • the images of the SEM image taken showed crystallites in the range 10 - 80 nm (estimate from SEM image), which are present as agglomerates.
  • the residual chlorine content was only a few ppm.
  • Example 2 40 g of the ruby powder obtained in Example 1 was suspended in 160 g of acetone. The suspension was deagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). The grinding beads used consisted of zirconium oxide (stabilized with yttrium) and had a size of 0.3 mm. After a grinding time of 3 hours, 5 g of H -tetrahydropane were added to the suspension and deagglomerated for a further hour. After separation of the grinding beads, a suspension of nanorubin in acetone was obtained.
  • the grinding beads used consisted of zirconium oxide (stabilized with yttrium) and had a size of 0.3 mm. After a grinding time of 3 hours, 5 g of H -tetrahydropane were added to the suspension and deagglomerated for a further hour. After separation of the grinding beads, a suspension of nanorubin in acetone was obtained.

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  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Nanotechnology (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Composite Materials (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Pigments, Carbon Blacks, Or Wood Stains (AREA)

Abstract

L'invention concerne un procédé pour réaliser un corindon coloré de taille nanométrique, selon lequel une solution aqueuse de chlorhydrate d'aluminium est mise à réagir avec des germes de cristallisation ainsi qu'avec un précurseur d'un formateur d'oxyde chromophore ou avec un oxyde chromophore, avant d'être séchée puis calcinée en moins de 30 minutes, les agglomérats obtenus étant ensuite fractionnés.
EP06754655A 2005-07-16 2006-07-01 Procede pour realiser un corindon colore de taille nanometrique Withdrawn EP1968894A1 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
DE102005033393.1A DE102005033393B4 (de) 2005-07-16 2005-07-16 Verfahren zur Herstellung von nanokristallinem α-Al2O3
DE102005039435A DE102005039435A1 (de) 2005-08-18 2005-08-18 Verfahren zur Herstellung von mit Silanen oberflächenmodifiziertem Nanokorund
DE102005039436A DE102005039436B4 (de) 2005-08-18 2005-08-18 Beschichtungsmassen enthaltend mit Silanen modifizierte Nanopartikel
DE102006012319A DE102006012319A1 (de) 2006-03-17 2006-03-17 Kosmetische Mittel enthaltend nanopartikuläres Korund
DE200610020515 DE102006020515B4 (de) 2006-04-29 2006-04-29 Nanopartikel aus Aluminiumoxid und Oxiden von Elementen der I. und II. Hauptgruppe des Periodensystems sowie deren Herstellung
DE200610020516 DE102006020516A1 (de) 2006-04-29 2006-04-29 Oberflächenmodifizierte Nanopartikel aus Aluminiumoxid und Oxiden von Elementen der I. und II. Hauptgruppe des Periodensystems sowie deren Herstellung
DE102006021705A DE102006021705B3 (de) 2006-05-10 2006-05-10 Verwendung von Mischoxid-Nanopartikeln in Beschichtungsmassen
PCT/EP2006/006431 WO2007009577A1 (fr) 2005-07-16 2006-07-01 Procede pour realiser un corindon colore de taille nanometrique

Publications (1)

Publication Number Publication Date
EP1968894A1 true EP1968894A1 (fr) 2008-09-17

Family

ID=36954592

Family Applications (1)

Application Number Title Priority Date Filing Date
EP06754655A Withdrawn EP1968894A1 (fr) 2005-07-16 2006-07-01 Procede pour realiser un corindon colore de taille nanometrique

Country Status (2)

Country Link
EP (1) EP1968894A1 (fr)
WO (1) WO2007009577A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007022821B4 (de) * 2007-05-15 2013-02-28 Clariant International Ltd. Spinnmasse für die Herstellung von Aluminiumoxid- und Mullitfasern und Verfahren zu deren Herstellung
DE102007024338A1 (de) * 2007-05-24 2008-11-27 Clariant International Ltd. Verfahren zur Herstellung von dotierten Yttriumaluminiumgranat-Nanopartikeln
WO2011144722A1 (fr) 2010-05-21 2011-11-24 Nestec S.A. Dispositif de stockage d'eau chaude ou de fourniture de vapeur
CN110312453A (zh) 2017-02-28 2019-10-08 雀巢产品有限公司 具有平行分配路径的分配器

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8531481D0 (en) * 1985-12-20 1986-02-05 Laporte Industries Ltd Alumina
DE4124630A1 (de) * 1991-07-25 1993-02-11 Starck H C Gmbh Co Kg Farbiger korund, verfahren zu seiner herstellung sowie dessen verwendung

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2007009577A1 *

Also Published As

Publication number Publication date
WO2007009577A1 (fr) 2007-01-25

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