EP1945592A2 - Particules reactives, procede pour les produire, utilisation de celles-ci dans des kits et ciments - Google Patents

Particules reactives, procede pour les produire, utilisation de celles-ci dans des kits et ciments

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Publication number
EP1945592A2
EP1945592A2 EP06807767A EP06807767A EP1945592A2 EP 1945592 A2 EP1945592 A2 EP 1945592A2 EP 06807767 A EP06807767 A EP 06807767A EP 06807767 A EP06807767 A EP 06807767A EP 1945592 A2 EP1945592 A2 EP 1945592A2
Authority
EP
European Patent Office
Prior art keywords
particles
ions
ionomer
elements
acid
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Withdrawn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
EP06807767A
Other languages
German (de)
English (en)
Inventor
Carsten Gellermann
Herbert Wolter
Thomas Ballweg
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.)
Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Original Assignee
Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
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 Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV filed Critical Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Publication of EP1945592A2 publication Critical patent/EP1945592A2/fr
Withdrawn legal-status Critical Current

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L24/00—Surgical adhesives or cements; Adhesives for colostomy devices
    • A61L24/0047—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material
    • A61L24/0073—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material with a macromolecular matrix
    • A61L24/0089—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material with a macromolecular matrix containing inorganic fillers not covered by groups A61L24/0078 or A61L24/0084
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/30—Compositions for temporarily or permanently fixing teeth or palates, e.g. primers for dental adhesives
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/80—Preparations for artificial teeth, for filling teeth or for capping teeth
    • A61K6/849—Preparations for artificial teeth, for filling teeth or for capping teeth comprising inorganic cements
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/80—Preparations for artificial teeth, for filling teeth or for capping teeth
    • A61K6/884—Preparations for artificial teeth, for filling teeth or for capping teeth comprising natural or synthetic resins
    • A61K6/887—Compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • A61K6/889—Polycarboxylate cements; Glass ionomer cements
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L24/00—Surgical adhesives or cements; Adhesives for colostomy devices
    • A61L24/04—Surgical adhesives or cements; Adhesives for colostomy devices containing macromolecular materials
    • A61L24/12—Ionomer cements, e.g. glass-ionomer cements
    • 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
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/28—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing organic polyacids, e.g. polycarboxylate cements, i.e. ionomeric systems
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/02—Compounds of alkaline earth metals or magnesium
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/28—Compounds of silicon
    • C09C1/30—Silicic acid
    • C09C1/3045—Treatment with inorganic compounds
    • C09C1/3054—Coating
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
    • C01P2002/82—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by IR- or Raman-data
    • 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
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/12—Surface area
    • 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
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00836—Uses not provided for elsewhere in C04B2111/00 for medical or dental applications

Definitions

  • the present invention relates to inorganic or optionally organically modified particles (ionomer particles) which can be subjected to leaching of certain cations in a targeted manner and thus are suitable for use as an inorganic component in so-called glass ionomer cements.
  • the invention further relates to processes for the preparation of these particles and their use in ionomer cements.
  • the term "ionomer particles” refers to inorganic particles which can be used in very varied ways as cements (self-hardening, photocurable, etc.) in combination with a preferably acid-containing matrix. In order for a cementing reaction to take place, these particles must be defined or intentionally unstable, i.e., in combination with water in the presence of the partner to which they are to bind, they must release metal ions which result in a hardening reaction in the partner substance.
  • Advantages of these materials are: little or no shrinkage up to an expansion due to the ionomer reaction as a result of water absorption, unproblematic incorporation of fluorides and phosphates, good bonding with the tooth tissue (or other body tissues such as bone) due to the acid groups in the matrix, simple application.
  • the basic structure of the usually glassy ionomers usually consists of the ternary system silica-alumina-calcium oxide. By melting these components, one obtains particles which undergo a two-stage reaction in the presence of, for example, polyalkenoic acids.
  • Glasionomerzemente Disadvantages of the Glasionomerzemente are still too low strength, the high abrasion and the low X-ray absorption, which can all be attributed to the previously used, conventionally ground glass ionomer particles.
  • the known ionomer particles can i.a. by melting together the respective starting compounds (mainly oxides).
  • the milling process to which the fused glass ionomer is subjected to obtain the desired particles promotes the formation of sharp-edged, non-circular particles.
  • the resulting abrasion resistance of the ionomer state is insufficient.
  • the particles formed are heterodisperse and relatively large and therefore generally have to be subjected to a complicated classification process in order to be able to be obtained in a size distribution which is even reasonably acceptable. In addition to high workload, this means a high loss of substance and thus extremely poor yields
  • the aluminum-silicate matrix is often not homogeneous due to the melting together.
  • the incorporation of fluorides in the form of droplets rich in calcium fluoride e.g. the incorporation of fluorides in the form of droplets rich in calcium fluoride.
  • WO 00/071082 discloses the use of a composition from the construction sector with the formula 3CaO SiO 2 to be strictly adhered to as a ceramic material in medicine. This material is also known as Portland cement. Under the
  • WO 00/05182 discloses particles produced in this way, which have a spherical or approximately spherical shape. These ionomer particles are either purely inorganic particles; but they can also be organically modified.
  • the ionomer particles which can be prepared according to WO 00/05182 contain, like the "classical" ionomer particles, at least three cationic components in their outer region, namely silicon ions, ions which can occupy the lattice sites of the silicon with formation of a negative charge surplus, eg aluminum, and ions , selected from among those of the elements of the first and second main group and other elements occurring in divalent form, which can compensate for the negative charge surplus, for example calcium.
  • a negative charge surplus eg aluminum
  • ions selected from among those of the elements of the first and second main group and other elements occurring in divalent form, which can compensate for the negative charge surplus, for example calcium.
  • the inventors of the present invention have surprisingly found that it is also possible to use those particles as ionomer particles in the glass ionomer cementation reaction which contain no more than two different cation species which are sparingly soluble as salts of polyalkenoic acids, provided they are wet-chemically (eg the sol-gel). Route) were made. Because of the wet-chemical preparation, the particles have a larger and more reactive surface than conventionally prepared particles (fired from glass or other oxides and / or ground). Because they have not been melted, they may also provide better interlocking with the polymer matrix.
  • the inventors were able to establish that there is no need for a network basis of SiO 2 in the inorganic matrix of the particles in which, as in the prior art, the other components are incorporated.
  • the presence of Si-O moieties can even mitigate the reactivity, which is not always desirable.
  • the invention provides ionomer particles having an inner region and an outer region, which are characterized in that the outer Area has an oxidic matrix with cations, the selection of the following
  • the oxidic matrix is preferably homogeneous or substantially homogeneous.
  • particles whose oxide matrix of calcium oxide and silicon oxide in a molar ratio of 3: 1 or contains this mixture, at least when the particles starting from calcium carbonate and finely divided silica (silica gel) with a Processes have been made, which requires the application of temperatures above 1000 0 C.
  • These particles are known from WO 00/71082.
  • the invention offers the possibility of much simpler than before and with the saving of at least one component and thus more cost-effective and in very great variability lonomerpumble provide or use. Due to the wet-chemical production, for example via the sol-gel route, the energy costs required for the production are low because no high melting or sintering temperatures are used.
  • the ionomer particles according to the invention may be particles having a (completely or substantially) homogeneous matrix of a mixed oxide of the two mentioned ionic species, which may contain particulate inclusions (for example fluoride salt (s), phosphate) and / or may be surface-modified. Then the inner and outer regions of the particles are identical.
  • the particles may be of the core-shell type. In this case, as mentioned above, the matrix surrounds a core which deviates in composition from that of the matrix.
  • the composition of the core is not critical, as this part of the particles does not participate in the ionomer reaction. It may therefore be chosen, for example, for the purpose of imparting additional properties to the particles, such as radiopacity or the like.
  • these particles may also contain particulate inclusions in their matrix region or be modified on their outside, as previously described for the homogeneous particles.
  • the ionomer particles further contain fluoride ions.
  • Fluoride ions are known to promote dental health through remineralizing effects (apatite formation).
  • the ionomer particles furthermore contain phosphate ions.
  • the cement reactivity in an advantageous manner in addition to the standard additives represent another instrument for setting the time for applicability essential time areas such as processing time and setting time and ultimately In terms of adhesion to the tooth and bone beneficial effect.
  • the oxide matrix of the particles is formed from a combination of elements of groups (a) and (b), groups (a) and (c) and groups (b) and (c). Among these combinations, those of groups (a) and (b) are particularly preferred.
  • Very particular preference is given to particles which contain calcium ions.
  • the individual particles according to the invention preferably have a spherical or approximately spherical shape. Particulate mixtures should preferably have a narrow particle size distribution. Their size is usually, but not necessarily, in the nanometer to micrometer range. The particle size can be adjusted, for example, to between 5 nm and 50 ⁇ m. Preference is given to the provision of relatively small particles, since they have more surface area.
  • Another advantage of smaller particles is an improved translucency of the resulting cement.
  • particle sizes are, for example, 20 nm to 20 ⁇ m or 0.5 ⁇ m to 50 ⁇ m; the selected particle size can be realized in a narrow distribution sector, which can be well below a power of ten. Smaller particles, for example in the range of 50 nm to 1 or 2 ⁇ m, are particularly well suited for dental fillings. In addition to the advantages already described, it is also possible to incorporate a particularly high proportion of ionomer in the case of small particles.
  • a mixture of two or three lots of ionomer particles is provided in a specific embodiment of the invention which, in their respectively defined narrow size distribution, have such a size relationship to each other that the smaller particles enter the Gaps of a densest packing of the larger particles thought fit and the possibly existing, still much smaller particles fit into gaps of the resulting packing.
  • This embodiment is particularly suitable for dental fillings, because a high ionomer content in the cement can be realized and mechanically demanding dental cements should contain the highest possible particle contents.
  • Bulk density is a parameter that provides information about the packing capacity of the particles. Thus, it can be estimated at an early stage to what extent high particle contents can be achieved.
  • larger particles are to be provided, whether as the largest batch of a size mixture, as described above, be it for the use of cements on other medical or off-medical fields (eg as bone substance or as an adhesive).
  • the particles are functionalized on their surface, which promotes the avoidance of agglomeration.
  • the particles are porous. porous
  • Particles ie, particles having pores on their outer surface
  • porous particles also have disadvantages: they result in a less mechanically stable cement. Therefore, the degree of porosity is selected for the desired purpose.
  • a lower porosity can then be selected if the particles are particularly reactive due to the ions used therefor, ie can be leached particularly strong in ionomer cement.
  • the porous glass ionomer particles preferably have a pore volume of from 0.001 to 2.0 cm-1, preferably from 0.01 to 1.5 cm-1, particularly preferably from 0.1 to 1.0 cm-1.
  • the pores are formed during wet-chemical production in low-temperature processes (sol-gel technology, emulsion processes, etc.). Among the wet-chemical
  • Reaction conditions initially arise clusters or primary particles of size 1 to 10 nm, which build up a network (gel) in the further course of the reaction.
  • the porous gel network can be more or less compacted or compacted.
  • the temperature range of below 500 0 C strongly porous systems result, it comes at temperatures above 800 0 C usually to form almost non-porous, but still generally amorphous glass ionomer.
  • the temperature range above 1000 ° C particulate systems are obtained, which have a glassy to ceramic character.
  • particles can be produced at high temperatures, which preferably have a low to no more porosity.
  • temperatures between 1,000 and 1,600 ° C sintered necks are first formed, and the individual components "flow together.” In these high-temperature processes, the pores disappear almost completely and dense particles are predominantly produced.
  • the particles may contain additives in homogeneous form or as particulate inclusions in said matrix. These additives can serve, for example, to increase the X-ray absorption capacity or to change the color, the transparency or the refractive index.
  • both particle variants, the homogeneous mixed particles as well as the particles of the core-shell type can be solved with the help of the sol-gel technology or other wet-chemical routes such as emulsion, aerosol, ink-jet or Stöberbacter produce.
  • the particles of the core-shell type are more elegant and less expensive to manufacture, since they have a shell, which is quite variable in thickness, of the mixed oxide matrix around an optionally very cheap core (eg of SiO 2).
  • the thickness of the shell can be adjusted according to the COOH content of the matrix.
  • Shell is therefore at least 10, preferably at least 50-100 times the radius of an MO group thick.
  • An upper limit can not be met because, as explained above, only the outer atomic layers determine the chemistry of the ionomer particles.
  • Additives such as those mentioned above may be present in the core and / or in the shell. This opens up the possibility of also possibly accommodating two incompatible additives in a particle type.
  • the preparation of the spherical ionomer particles succeeds, in particular, by way of various wet-chemical processes.
  • an organic component-containing dispersion is formed in which a controlled hydrolysis and condensation takes place.
  • the term "dispersion” is used herein although it may be possible to obtain true solutions, suspensions, or emulsions, or at certain stages of hydrolytic condensation.
  • sol and gelation processes should be encompassed by the term (eg, the disperse phase of a dispersion or emulsion may gel). He is therefore correspondingly broad to understand.
  • the dispersion can be converted into spherical particles in various ways, for example via the so-called Stöber process or spray drying.
  • organic compound is to be understood as meaning any "organometallic” compound which has at least one organic constituent bonded or complexed to the metal via oxygen or an organic constituent bonded to the metal in the presence of water, aqueous or other solvents or dispersants (eg alcohols) can use an at least partial hydrolysis of this compound, which possibly also starts only under the action of acid or base, whereupon the compound undergoes a controlled condensation, so that in the "solvent” chain or Form network condensates, but no uncontrolled precipitation reactions occur (the term “solvent” is of course to be understood that the agent is not a real solution of the organic compound (s) will cause it usually creates a suspension, a dispersion, an emulsion, a sol or a gel).
  • solvent is of course to be understood that the agent is not a real solution of the organic compound (s) will cause it usually creates a suspension, a dispersion, an emulsion, a sol or a gel).
  • organic compounds are, for example, oxo complexes, such as alcoholates or carboxylates, but also other suitable metal complexes or organometallic compounds. Depending on requirements, both cations of the later spherical particles can be used in the form of said organic compounds.
  • the organic component not only but in particular the carboxylates and alcoholates are suitable.
  • Particularly preferred are magnesium, calcium and strontium acetate and the alcoholates, for example isopropanolates, of these elements.
  • Further examples are calcium acetylacetonate or calcium oxalate.
  • this cation should not be used as an organic component, possibly extremely fine powders of the corresponding inorganic compounds, for example, the oxides, halides (chlorides, fluorides), phosphates or other Salts (eg Ca (NO 3 ⁇ , MgCl 2, SnCl 2)) Because these powders may not dissolve completely and therefore clusters, eg oxide clusters, can remain with predominantly one type of cation, the oxidic matrix may not be completely homogeneous. It is therefore sometimes also referred to as "substantially homogeneous.”
  • the clusters should advantageously be less than 50 nm in diameter, typically less than 10 nm in diameter.
  • the metals among which the cations of the group mentioned under (a) can be selected, include e.g. Beryllium, magnesium, calcium, strontium and barium, but also strontium, tin or zinc (the latter in its divalent form).
  • suitable cations specific properties can be specifically produced, for example, X-ray opacity, reactivity, optical properties or the like.
  • oxo complexes are preferably used for this purpose.
  • oxo complexes are, for example, alkoxides, diketonates and carboxylates.
  • alcoholates are ethanolate, secondary and tertiary butylate, for example of aluminum.
  • carboxylate is exemplified that of oxalic acid or methacrylic acid.
  • acetates or acetylacetonates and other complexes with chelating agents come into question.
  • this cation should not be used as an organic component, the use in the form of soluble or insoluble in the selected solvent, possibly extremely fine powders of corresponding inorganic compounds, for example the oxides, halides (chlorides, fluorides), phosphates or other salts (eg AICI3), to.
  • corresponding inorganic compounds for example the oxides, halides (chlorides, fluorides), phosphates or other salts (eg AICI3), to.
  • Further examples are ethylaluminum dichloride, iron (III) fluoride, iron (III) citrate, iron acetylacetonate.
  • the elements which can be used under (b) are preferably those of the third main group, with gallium, indium and thallium. Also trivalent niobium, trivalent tantalum, scandium, yttrium and rare earths such as lanthanum, cerium, gadolinium, ytterbium come into consideration. By selecting specific elements, e.g. very heavy elements, certain properties such as radiopacity can be generated. Aluminum is of limited scope for this group. Depending on the choice of the second component and the degree of porosity and thus the reactivity of aluminum-containing particles, their ion release rate can be so high that it is not ensured in all cases falls below a sufficient safety distance to the toxicity limit.
  • Examples of starting compounds for the incorporation of cations of group (c) are titanium (IV) butoxide, zirconium butoxide, zirconium acetate, n-butyltin trichloride, tin (IV) acetate, tin (IV) sulfate.
  • silicon as an element of group (c) is less favorable because it may be necessary to accept a reduction in reactivity.
  • silicon is to be used as an element of group (c) for certain reasons, for example in combination with a particularly reactive partner, and this cation is to be used as an organic component
  • hydrolyzable silanes or siloxanes can be added to the dispersion, for example alkyl- and / or alkoxysilanes. In this case one arrives at particles with a homogeneous silicate-containing matrix.
  • a dispersion with compounds of the complexed elements mentioned in group (a), (b) or (d), e.g. a second dispersion of very small diameter silica particles is admixed.
  • the silica forms cluster-like structures within the outer region of the forming particles which, because of their small diameter, are very well cross-linked with the oxide of the other element.
  • Examples of starting compounds for the incorporation of cations of group (d) are tantalum (IV) butoxide, tantalum (V) chloride, ammonium heptafluortantalate (V). If particles of two types of cations, selected from silicon, aluminum and calcium, are to be produced in spite of the abovementioned restrictions, the starting compounds are alkoxysilanes, aluminum alcoholates and calcium acylate.
  • aluminum butylate may be used with calcium acetate or aluminum butylate or calcium acetate, each in combination with silica.
  • oxide matrix of the ionomer particles contain phosphate, this can be added in the form of triethyl orthophosphate. Fluoride incorporation can be via hexafluorosilicic acid or ammonium fluoride.
  • tin dioxide particles can be added to the above-mentioned dispersion.
  • tin dioxide particles can be added into a sol containing the aforementioned components. This makes it possible to obtain spherical particles with an inner region (core) made of tin dioxide, which ensure, for example, good X-ray absorption.
  • the core of the ionomer particles may instead consist of silica;
  • silicon dioxide particles of the appropriate size eg with a diameter of 30-100 nm (eg for the dental sector) or from 1 to 2 ⁇ m
  • the aforementioned ionomer-reactive modifications are given by way of example only; All possible variants can be carried out as long as the ionomer particles have the above-mentioned ionomer-reactive constituents in their outer region.
  • organically modified constituents for producing the dispersion can be introduced, for example, into water and optionally combined with vinegar or glacial acetic acid (or added to the already acidified solvent).
  • Basic solvents are also possible.
  • the organically modified components for example, in a non-aqueous Dipersionsstoff, such as an alcohol, in a suitable manner for the required hydrolysis processes sufficient amount of water and optionally base or acid are added as a catalyst.
  • the optionally co-processed inorganic substances can be incorporated, which may be previously dissolved or dispersed.
  • a dispersion is formed, which can then be converted into preferably spherical or approximately spherical particles, or from which such particles are separated off.
  • This can be done in various ways known to those skilled in the art.
  • inert particle cores eg SiO.sub.2, SnO.sub.2 cores
  • a shell containing silicon ions the additional elements of group (a) or (b), if appropriate also contains (d).
  • the nuclei used can be any monodisperse, spherical germs produced. Et al Commercially available, agglomerate-free, monodisperse, spherical SiO 2 (for example Ludox, from DuPont) or SnO 2 particles are suitable.
  • monodisperse spherical SiO.sub.2 cores in the size range from 50 to 2000 nm, which are then provided with a "shell".
  • organosilicon compounds such as alkoxysilanes in combination with compounds of group (a) or (b) (the latter two in organic or inorganic form), optionally instead of group (d).
  • the organic compounds or a low molecular weight condensation product thereof for example, to 1-40 wt .-% of a solvent, preferably an alcohol added.
  • This solution is titrated in the manner of the mother dispersion of the cores, that in the course of the growth process of the particles a supersaturation concentration that would lead to the formation of new particles is not reached. Since the organic compounds are to be hydrolyzed by this method, water is added in a concentration which is adapted to the concentration of the educts.
  • a pH of 8-9 is beneficial for uniform growth of the particles and provides nearly perfectly spherical, monodisperse ionomer particles. These are characterized by a surprisingly fast ionomer reaction.
  • An in situ surface modification is achieved, inter alia, by adding a silane, for example of aminopropyltriethoxysilane or methacryloxypropyltrimethylsilane, in the form of a 1-100% strength by weight solution for dispersion.
  • the solvent used is preferably the same solvent of the mother dispersion, for example ethanol.
  • a subsequent surface modification of the dried particles for this purpose, the particle powder to about 10 wt .-% in an organic solvent such as toluene, suspended, added to the monomolecular occupancy necessary amount of silane, optionally added to a catalyst and optionally refluxed.
  • emulsion processes are also very suitable for the preparation of the ionomer particles described above.
  • the O / W and W / O methods can be used.
  • the W / O method is used (see, for example, EP 0363927).
  • the proportion of the aqueous phase is preferably about 15 to 45 vol .-%, of the emulsifier is preferably about 1 to 20 wt .-%.
  • Precipitation or gelation takes place in the water droplets during the course of the emulsion process, which is preferably initiated by a basic pH shift.
  • Suitable starting compounds are salts and organic complexes of the elements already described above, preferably nitrates, alcoholates and acetates, and also dispersions already prepared therefrom without restriction. Surprisingly, the resulting ionomer particles have a narrow size distribution, which can be significantly below one order of magnitude.
  • the liquid described above may also be subjected to an aerosol treatment, in particular a spray drying.
  • a spray drying For example, very finely dispersed SiO 2 particles or silicon alkoxides can be mixed with alcoholates or carboxylates of the cations of groups a) or b) in aqueous solution with a pH of ⁇ 7. With the aid of suitable nozzles, droplets are sprayed which have a spherical shape. These may optionally be dried, for example at about 250 ° C., until the volatile organic compounds have been removed.
  • Ingredients are present (for example, at 400 ° to 600 0 C). This produces hydrocarbon-free ionomer particles.
  • Temperatures above about 1000 ° C. are often undesirable because the individual particles melt together irreversibly to form an aggregate.
  • the particles may have a continuous homogeneous range of calcium silicates, strontium silicates, aluminum silicates or the like.
  • the ionomer particles may consist solely of these structures or may have a discrete internal region which has a different composition, for example silica, tin dioxide, a mixture of both, aluminum silicate or the like.
  • the spherical ionomer particles consist of an inner region and a plurality of outer, preferably cup-shaped regions.
  • spherical ionomer particles of the invention can also be silanized or otherwise surface-modified in the usual way.
  • cementitious materials e.g. Composites, cements, compomers.
  • Their properties can be adjusted as described, by using appropriate starting materials targeted, e.g. by the addition of X-ray opaque ingredients or by reaction conditions (e.g., concentration, temperature, pH) which allow the diameter of the particles to vary.
  • reaction conditions e.g., concentration, temperature, pH
  • materials with different transparency, color, different refractive index can be adjusted.
  • the ionomer particles according to the invention can be incorporated into a multiplicity of different organic or partially organic matrices, with which they undergo a glass ionomer reaction (cement formation).
  • Glass ionomer cements are formed by the reaction of inorganic glass ionomer particles with an acidic Matrix system formed in the presence of water.
  • the acidic matrix system can be organic in nature and is then usually a carboxyl-containing polymer matrix system, for example one of one (or more) polyalkenoic acid (s).
  • the matrix system may be a homopolymer or a copolymer of unsaturated mono-, di- or higher polycarboxylic acids (eg mono-, di- or tricarboxylic acids) or their anhydrides or mixtures thereof. Hydroxycarboxylic acids such as citric acid or tartaric acid can be added to the acidic matrix system.
  • polyacrylic acid As selected examples here are polyacrylic acid, polyitaconic acid and
  • the matrix system may also include an acidic inorganic-organic hybrid polymer, e.g. a carboxyl group-containing hybrid polymer such as e.g. such in the
  • the matrix system may also contain polymerizable monomers which can be converted to a polymer system via a curing reaction (e.g., UV, light, redox induced).
  • a curing reaction e.g., UV, light, redox induced
  • the proportion of these monomers is very high (up to 100%), so that the glass ionomer reaction is influenced by the monomers and the polymerization conditions.
  • acid matrix systems are possible, e.g. those with polyphosphonic acids such as poly (vinylphosphonic acid), systems which additionally contain photocurable constituents or matrices which can form the above-described compomers with ionomer particles.
  • Highly suitable acidic matrix systems for the glass ionomer particles of the present invention have preferred molecular weights, e.g. for polyacrylic acid are from 2,000 to 200,000, more preferably from 10,000 to 100,000. For other polyacids, the molecular weights may be calculated accordingly. If the molecular weight is too large, gel formation may occur which prevents the further glass ionomer reaction between the particles and the acidic matrix and adversely affects the compressive strength of the cement.
  • the mixing ratio (mass ratio) of acid to particles is favorably 0.001: 1 to 10: 1 and preferably between 1: 5 and 5: 1. If the latter In some cases, excessive proportions of acid or base in the cement may arise, which may have a negative effect, for example, with regard to the desired biocompatibility or the dentin adsorption capacity.
  • Suitable matrix systems with which the ionomer particles according to the invention can be processed into cements are the acidic systems already mentioned in detail above. These can be provided in the aqueous phase or freeze-dried; In the latter state, of course, water must be added when mixing with the ionomers.
  • the glass ionomer reaction takes place in an excess of the reaction medium water.
  • the mixing ratio of water to glass ionomer particles and acid-containing matrix is preferably from 0.01 to 100, particularly preferably from 0.1 to 10.
  • the concrete water content may be critical in some cases, exact limits are hardly given, as they are strongly dependent on the Composition, particle size, porosity and specific surface area of the glass ionomer particles. If the water content is too low, the release of ions is too low, which does not allow sufficient application and sufficient mechanical properties such as compressive strengths. But too high water contents can be critical, as it could then come to the formation of loose gel networks due to high ion releases. Gels are, as mentioned above, undesirable mainly because of their poor mechanical properties.
  • the reaction between the particles and the acidic matrix is preferably carried out in the normal reactor or in a small shaker (eg VOCO Mix 10).
  • a reaction in an autoclave is possible.
  • Temperatures from room temperature to 80 0 C are suitable, preferably 20 to 40 0 C is selected.
  • accelerators can be used.
  • these are complexing agents, for example citric acid or tartaric acid up to levels of 15 wt .-%, preferably up to about 5 wt .-%.
  • Other additives such as stabilizers, detergents, dispersing aids, pigments, etc. are possible.
  • other fillers, ie inactive and active fillers may be added to the reactive glass ionomer particles. This is always useful if too high a porosity of the cement to achieve good mechanical properties to be compensated.
  • ion releases after 24 hours have been found to be from 0.01 mg / l to 500 mg / l (data as metal oxides). Releases of preferably from 1 to 100 mg / l and very particularly preferably from 10 to 50 mg / l have proven particularly suitable. However, lonomer cements are also useful whose ion release values are outside the broader range mentioned above.
  • low-barium or non-barium compositions are preferred for realizing possibly desired high radiopacities.
  • These may contain other heavy elements such as preferably Sr, Y, Sn and the lanthanides or more preferably Zr, Nb or Ta.
  • the particles of the present invention can be used as exclusive fillers or combination fillers for dental cements, dental composites, bonding agents, toothpastes, dental primers, bonding primers, adhesive dental cements, self-curing composites, self-etching composites, fissure sealants, dental varnishes, abrasion fillers, temporary sealants, root fillers, mouthwashes, and the like be used.
  • dental cements dental composites, bonding agents, toothpastes, dental primers, bonding primers, adhesive dental cements, self-curing composites, self-etching composites, fissure sealants, dental varnishes, abrasion fillers, temporary sealants, root fillers, mouthwashes, and the like be used.
  • dental cements dental composites
  • bonding agents toothpastes
  • dental primers bonding primers
  • adhesive dental cements self-curing composites
  • self-etching composites self-etching composites
  • fissure sealants dental varnishes
  • abrasion fillers temporary sealants
  • Example 1 (SiO 2 / Al 2 O 3 particles, weight ratio: 75/25) 7.9 g of aluminum sec-butoxide were added at RT with stirring with 30 ml of water and glacial acetic acid. The resulting Al-containing solution was added dropwise to a dispersion obtained by diluting 12.3 g of a commercial SIO 2 sol (Kiesol Ludox AS40, DuPont) with 75 g of water and 2 ml of glacial acetic acid. After the spray-drying at about 250 0 C a white powder was obtained which, according to SEM images consisting of approximately spherical particles. Measurements by X-ray fluorescence (XRF) confirm a SiO 2 / Al 2 O 3 ratio that is similar to the educt ratio. A temperature treatment by continuous heating in a muffle furnace up to 800 0 C followed.
  • XRF X-ray fluorescence
  • the particles having dissolved in water commercial polycarboxylic acid (polyacrylic acid, MW 60,000) or a carboxylic acid-containing hybrid polymer (ORMOCER ®) resin were mixed. Hardening of the mixture occurred via an ionomer reaction, which was detected by means of FTIR spectroscopy of the forming COO-Al bonds by asymmetric vibrations at about 1593 cm -1 .
  • Example 2 SiO 2 / CaO particles, weight ratio: 75/25)
  • Polycarboxylic acid polyacrylic acid, MW 60,000
  • ORMOCER ® carboxylic acid hybrid polymer
  • a hardening of the mixture occurred via an ionomer reaction, which was detected by means of FTIR spectroscopy of the COO-Ca bonds forming on the basis of asymmetric vibrations at about 1555 cm -1 .
  • Example 3 Al 2 O 3 / CaO particles, weight ratio: 50/50
  • 7.7 g of aluminum sec-butoxide were added at RT with stirring with 30 ml of water and glacial acetic acid.
  • the particles having dissolved in water commercial polycarboxylic acid (polyacrylic acid, MW 60,000) or a carboxylic acid-containing hybrid polymer (ORMOCER ®) resin were mixed. Hardening of the mixture occurred via an ionomer reaction, which was detected by means of FTIR spectroscopy of the COO-Ca or COO-Al bonds forming on the basis of asymmetric vibrations at about 1556 and 1594 cm -1, respectively.
  • Example 4 Al 2 O 3 / SrO particles, weight ratio: 50/50
  • 8.0 g of aluminum sec-butoxide were added at RT with stirring with 30 ml of water and glacial acetic acid.
  • a solution of 3.3 g of strontium acetate was added at RT with vigorous stirring with stirring with 20 ml of water and 1 ml of glacial acetic acid and then diluted with 50 g of water.
  • After spray-drying at about 250 ° C. a white powder was obtained.
  • RFA measurements confirm an A ⁇ O ß / SrO ratio, which is similar to the educt ratio.
  • a temperature treatment by continuous heating in a muffle furnace up to 800 0 C followed.
  • Hybrid polymer (ORMOCER ®) resin. Hardening of the mixture occurred via an ionomer reaction, which was detected by means of FTIR spectroscopy of the COO-Sr or COO-Al bonds formed by asymmetric vibrations at about 1556 and 1590 cm -1, respectively.
  • Example 5 (SnO 2 / CaO particles, weight ratio: 75/25)
  • the temperature was maintained at 300 ° C. for a period of 30 minutes.
  • the resulting particles had a diameter of 4.7 ⁇ m (volume distribution) measured by Fraunhofer diffraction.
  • the specific surface area determined by N 2 sorption to BET was 121 m 2 / g.
  • the particles having dissolved in water commercial polycarboxylic acid (polyacrylic acid, MW 60,000) or a carboxylic acid-containing hybrid polymer (ORMOCER ®) resin were mixed.
  • a hardening of the mixture occurred via an ionomer reaction, which was detected by FTIR spectroscopy of the forming COO-Ca bonds by asymmetric vibrations at about 1556 cm -1 .
  • Example 6 SiO 2 / CaO particles, weight ratio: 75/25, F-containing 4.7 g of calcium acetate were added at RT with stirring with 20 ml of water and 1 ml of glacial acetic acid. The resulting Ca-containing solution was added dropwise to a dispersion obtained by dilution of 12.3 g of a commercial SiO 2 sol (Kiesol Ludox AS40, Grace Davison) with 75 g of water and 0.5 g of hexafluorosilicic acid. After spray-drying at about 250 ° C., a white powder was obtained which, according to SEM images, consists of approximately spherical particles. RFA measurements confirm an SiO 2 / CaO ratio that is similar to the reactant ratio. A temperature treatment by continuous heating in a muffle furnace up to 800 0 C followed.
  • a temperature treatment was carried out by a continuous heating in a muffle furnace up to 800 0 C, which was supplemented at 300 0 C by a holding time.
  • the resulting particles had a diameter of 4.5 ⁇ m (volume distribution) measured by Fraunhofer diffraction.
  • the BET specific surface area determined by N 2 sorption was 76 m 2 / g.
  • the particles having dissolved in water commercial polycarboxylic acid (polyacrylic acid, MW 60,000) or a carboxylic acid-containing hybrid polymer (ORMOCER ®) resin were mixed.
  • a hardening of the mixture occurred via an ionomer reaction, which was detected by means of FTIR spectroscopy of the COO-Ca bonds forming on the basis of asymmetric vibrations at about 1555 cm -1 .

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Abstract

La présente invention concerne des particules d'ionomère présentant une région intérieure et une région extérieure, caractérisées en ce que la région extérieure présente une matrice d'oxydation avec des cations qui est choisie selon les conditions suivantes : il ne doit y avoir que deux types de cations différents qui appartiennent à un des groupes (a) à (d) suivants et qui doivent être choisis parmi deux groupes différents des groupes (a) à (d) suivants : (a) des ions des éléments du deuxième groupe principal et des ions bivalents des éléments de transition et des lanthanides (b) des ions des éléments du troisième groupe principal, à l'exception du bore, et des ions trivalents des éléments de transition et des lanthanides (c) des ions des éléments du quatrième groupe principal, à l'exception du carbone, et des ions tétravalents des éléments de transition et des lanthanides (d) des ions des éléments du cinquième groupe principal choisis parmi des ions d'antimoine et de bismuth et des ions pentavalents des éléments de transition. Cette invention concerne également des procédés pour produire ces particules d'ionomère, des kits pour produire des ciments destiné à un usage dans le domaine médical ou dentaire, qui contiennent lesdites particules d'ionomère et une matrice polymère durcissable séparée, ainsi que les ciments ainsi produits et les utilisations des particules d'ionomère et des kits.
EP06807767A 2005-11-10 2006-11-07 Particules reactives, procede pour les produire, utilisation de celles-ci dans des kits et ciments Withdrawn EP1945592A2 (fr)

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DE102011050672B4 (de) 2011-05-27 2020-06-25 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Kieselsäure(hetero)polykondensate mit (Meth)acrylresten und entweder Sulfonat- oder Sulfatgruppen, für deren Herstellung geeignete Silane sowie Verfahren zum Herstellen der Kondensate und der Silane
WO2012163781A1 (fr) 2011-05-27 2012-12-06 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Composés comprenant des radicaux (méth)acrylate et des groupes sulfonate ou sulfate, polymères et condensats à partir de ceux-ci et utilisation des polymères et des condensats

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DE19508586C2 (de) * 1995-03-13 1997-07-10 Degussa Polymerisierbarer Dentalwerkstoff
DE59711025D1 (de) * 1996-09-30 2003-12-24 Degudent Gmbh Polymerisierbarer Dentalwerkstoff und Verwendung von Apatit-Füllstoffen im Dentalwerkstoff
DE19643781C2 (de) * 1996-10-29 2000-01-27 Fraunhofer Ges Forschung Sphärische Partikel auf der Basis von Metalloxiden, Verfahren zu deren Herstellung und deren Verwendung
DE19832965A1 (de) * 1998-07-22 2000-02-03 Fraunhofer Ges Forschung Sphärische Ionomerpartikel und deren Herstellung
US6306926B1 (en) * 1998-10-07 2001-10-23 3M Innovative Properties Company Radiopaque cationically polymerizable compositions comprising a radiopacifying filler, and method for polymerizing same
DE19846660A1 (de) * 1998-10-09 2000-04-13 Inst Oberflaechenmodifizierung Hochtemperaturbeständige polymerisierbare Metalloxidpartikel
US7432385B2 (en) * 2001-03-13 2008-10-07 Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V. Phosphorous-containing, organic polymerisable silanes and silicic acid polycondensates produced therewith

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Title
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