DE102008028306A1 - Polymerizable, nanodiamond-containing dental material, obtained by cleaning, for at least one time, the nanodiamond with e.g. acid and incorporating into the dental material, useful as e.g. filler materials and binding materials - Google Patents

Abstract

Polymerizable, nanodiamond-containing dental material, obtained by cleaning, for at least one time, the nanodiamond with at least one acid, at least one organic solvent and/or at least one chelating agent and incorporating the cleaned nanodiamond into the dental material, is claimed. Independent claims are included for: (1) the dental material with redox initiator system comprising an initiator and a coinitiator, where the initiator and the coinitiator are present in components that are spatially separated from each other, preferably present in two-component system; (2) hardened dental material obtained from the polymerizable dental material; and (3) a method for preparing nanodiamond-containing dental material comprising cleaning, for at least one time, of the nanodiamond with at least one acid, at least one organic solvent and/or at least one chelating agent, optionally washing and/or neutralizing the nanodiamond, with distilled water, preferably with chloride-free water, optionally drying the nanodiamond and incorporating the nanodiamond in the dental material.

Description

The The invention relates to a polymerizable, storage-stable dental material with nanodiamond.

Polymerizable dental materials in which an organic phase is combined with an inorganic phase are familiar to the person skilled in the art as "composites" and are described in detail, for example Ullmann's Encyclopedia of Industrial Chemistry, 6th Edition, Volume 10, page 355 et seq. (denture base resins). The organic phase usually consists of dental resins, usually acrylates and methacrylates, in which the components of the initiator system and possibly further additives are dissolved. The inorganic phase usually consists of fillers in the nanometer to micrometer range. Also is off EP-A-1 913 927 known to incorporate nanodiamonds in dental composites to improve their mechanical properties.

It is known to be a set of substances for the human Body are poisonous. For example, all water or acid-soluble barium compounds and a Series of heavy metals, in particular dissolved lead and Lead compounds are toxic to the human organism. Even the smallest quantities, over a longer period of time steadily taken, accumulate in the body and can cause chronic poisoning. This is especially for Children and pregnant women are dangerous. The same applies for some organic tin compounds, for example the trialkyltin compounds, because of their toxicological effect u. a. used in paints for ships around Prevent infection of microorganisms and mussels.

consequently is based on the use of toxicologically hazardous substances in the dental field as far as possible omitted. This is especially true for Dental materials that make up the toxicologically questionable substances diffuse out or can be washed out by saliva and be absorbed by the organism.

chemical curing polymerizable dental materials (in the literature often also self-curing or autocatalyzed Called dental materials) contain polymerizable monomers, their polymerization triggered by radicals formed primarily becomes. The formation of these radicals takes place by the reaction of a suitable Initiator molecule, which at room temperature alone sufficient Has storage stability, with a coinitiator. This one Reaction immediately after the combination of initiator and coinitiator begins, both have to store the dental materials Components of the initiator system can be housed separately.

An initiator system most commonly used in the prior art for chemically curing dental materials consists of a mostly aromatic amine and an organic peroxide, such as, e.g. In DE-C-97 50 72 described. The required radicals are formed in this system via a redox reaction in the meeting of amine (coinitiator) and peroxide (initiator).

For Commercial use requires several dental materials Be storable for months to several years. Although dental materials based on a redox initiator system usually are offered as multicomponent systems in which the two Components, the initiator and the coinitiator, in separate primary containers (Cans, tubes, syringes, bottles, etc.) or in primary containers with separate chambers (eg double cartridges) are housed, It may nevertheless be subject to restrictions on the durability of such Materials by premature polymerization of one or more Pastes come.

mostly the paste is affected, which is the actual initiator molecule contains (eg peroxide, CH-acidic compounds or compounds, which release such acids). But also the paste, the containing the coinitiator can be affected. Possible Causes are the mutual contamination of both pastes, thermal effects, insufficient stabilization by suitable radical scavengers, Impurities of raw materials or the presence costartend acting organic groups on active surfaces such as for example, amino groups.

Of the present invention are the two objects mentioned below based.

The primary (first) task is a polymerizable To create dental material with nanodiamond, that for the Organism is toxicologically harmless.

Of the present invention is the secondary (second) task based, a polymerizable dental material with a redox initiator system and with nanodiamonds to create that better storage stability having.

The Invention solves the first object by a polymerizable Dental material with the features of claim 1 and a method with the features of claim 13. Preferred embodiments The invention are in the claims 2-12 and 14-15 discloses.

The the invention in fact solves the aforementioned first object is proved by the examples and will be briefly explained below.

The Invention has in solving the first problem in one First step realized that nanodiamond a surprising high proportion of possible toxic substances, in particular at the heavy metals lead and tin as well as barium in a for The dental field has unacceptable dimensions.

The Invention has in solving the first problem in one Second step recognized that a number of toxicological questionable substances in nanodiamonds, in particular lead, tin and Barium, before being processed in dental material to a toxicological let deprive harmless measure.

The Invention solves the second object by a polymerizable Dental material with the features of claim 2 and a method having the features of claim 13, wherein the redox initiator system is at least having an initiator. Preferred embodiments The invention are in the claims 3-12 and 14-15 discloses.

The the invention in fact solves the aforementioned second object is proved by the examples and will be briefly explained below.

The Inventors have found that the premature polymerization process to a particularly great extent in the case of polymerizable dental materials occurs with a redox initiator system in which conventional Dental glass filler (eg Aerosil) by nanodiamond powder was replaced. While that filled with Aerosil, nanodiamond-free nanocomposite is stable on storage, resulting in the Use of nanodiamond as nanoscale filler instabilities. Even with proper storage at room temperature begins the containing the initiator of the redox initiator system Component (initiator paste) after a short time (a few hours to days) and then polymerizes after a short time. Such storage-unstable pastes can be used for dental materials Not used.

The Invention has in the solution of the second task initially realized that nanodiamant a surprisingly high proportion has transition metal ions, in particular iron, Chromium, manganese, copper and nickel acting as a coinitiator for the initiator of the redox initiator system come into consideration. The Inventors assume that if the initiator and the nanodiamond with the coinitiator transition metal ions in one component (eg in an initiator paste), the initiation of the redox initiator system and thus the radical formation is favored, what a undesired polymerization of the component (initiator paste) according to pulls.

The Invention has in solving the second problem in one further step, that the coinitiator transition metal ions, especially iron, chromium, manganese, copper and nickel from nanodiamonds deplete before processing in the dental material, so that these no longer to the same extent as before as unwanted Coinitiatoren in the redox initiator system are available.

According to the invention the nanodiamonds before incorporation into the polymerizable dental material at least once with at least one acid and / or at least an organic solvent and / or at least one Chelating agent at least once, preferably twice, more preferably three times, more preferably four times, more preferably five times, more preferably six times, more preferably seven times, further preferably eight times, more preferably nine times, more preferably ten times, more preferably more than ten times, optionally washed and / or neutralized, preferably with distilled Water, more preferably with chloride-free water and optionally dried.

Of the Cleaning step can or cleaning steps can 1-600 min, 5-500 min, 10-400 min, 15-300 min, 20-250 min, 25-200 min, 30-150 min and combinations of the aforementioned times.

Since, in particular, the chlorides of the transition metal ions are readily water-soluble, treatment of the nanodiamond powder with hydrochloric acid, preferably with concentrated (37%) hydrochloric acid, is preferred. Furthermore, because of the water solubility of most of their salts, hydrochloric acid may be advantageously used instead For example, nitric acid or sulfuric acid can be used to pretreat the nanodiamond powder. It is also possible to use organic acids, provided that the reaction rate of the reaction of the impurities contained in the nanodiamond lies within a meaningful range. Suitable organic acids may be sulfonic acids or monocarboxylic acids selected from the group consisting of formic acid, acetic acid and benzoic acid or derivatives of these acids or dicarboxylic acids selected from the group consisting of oxalic acid, malonic acid, succinic acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, maleic acid, Fumaric acid, sorbic acid, phthalic acid and terephthalic acid or derivatives of these acids or tricarboxylic acids, selected from the group consisting of hemimellitic acid, trimellitic acid, trimesic acid, Agaricinsäu re, citric acid, 1,2,3-propane tricarboxylic acid or derivatives of these acids or multicarboxylic acids selected from Group consisting of pyromellitic acid and mellitic acid or derivatives of these acids or polycarboxylic acids, selected from the group consisting of polyacrylic acid and polymethacrylic acid or derivatives of these acids. The acids may contain one or more polymerizable groups, for example (meth) acrylic groups. Also possible is the reaction with organic acids to form non-water-soluble salts and dissolving with organic solvents. For technical processes, however, acid leaching with hydrochloric acid should have clear advantages.

Another possibility for the selective dissolution of ions is the complex formation. Well-known complexing agents are summarized by G. Schwarzenbach under the name Komplexon aminopolycarboxylic acids which form stable chelate complexes with polyvalent metal ions. Since the chelation takes place in a rapid reaction, these compounds are also used in the chemical analysis for complexometric titration ( G. Schwarzenbach: "The complexometric titration" 4th ed. Stuttgart 1960 ). The most commonly used chelating agents are complexone I (NTE = nitrilo-triacetic acid: N- (CH ₂ -COOH) ₃ ), complexone II (EDTA = ethylenediamine-tetraacetic acid: (HOOC-CH ₂ ) ₂ -N-CH ₂ -CH ₂ -N- (CH ₂ -COOH) ₂ ) and complexone III (disodium ethylenediaminetetraacetic acid).

According to one preferred embodiment of the invention comprises the inventive Method further comprises at least one thermal treatment the nanodiamonds, the nanodiamonds preferably being tempered, d. H. heated to a temperature below the melting temperature are (preferably 15-120 min., More preferably 30-105 min., more preferably 45-90 min., more preferably 45-75 min., More preferably 60 min.), More preferably at 400-450 ° C more than 0.5 hours, especially preferably heated at 425 ° C for 1 h.

The Thermal treatment may be, for example, as in the procedures according to Example 6a and 6b, with the cleaning of Nanodiamonds one or more times, alternating in any order.

The Nanodiamonds are dispersed in the organic resin matrix. Further fillers and additives are subsequently added stirred into the nanodispersion thus obtained.

Of the Total content of nanoparticles (including nanodiamond) in the polymerizable dental material is preferably not larger as 25% by weight, preferably less than 23% by weight, more preferably less than 21% by weight, more preferably 15-20% by weight, further preferably 16-19% by weight, more preferably 17-19 Wt .-%, particularly preferably 17.5-18.5 wt .-%.

According to the invention preferred For example, the organic phase is selected from polymerizable monomers from the group consisting of acrylic acid ester and methacrylic acid ester. The resin matrix can also consist of monomers which ring-opening and / or polymerize ionically. As the organic phase according to the invention a Used compound or a mixture of several compounds, the free-radically and / or cationically and / or anionically polymerizable Groups and / or groups undergoing curing a condensation and / or addition reaction and / or over allow an acid-base reaction contains. The Connections consist of a Phosphazene-based, silicon-based or organic (carbon-based) backbone and at least one functional group attached to this backbone is bound and the one about a radical and / or cationic and / or anionic polymerization reaction and / or via a condensation and / or addition reaction and / or over an acid-base reaction proceeding curing allowed. These functional groups are preferred acrylate, methacrylate, cyanoacrylate, acrylamide, methacrylamide, Vinyl, allyl, epoxide, oxetane, vinyl ether, amino, acid, Acid ester, acid chloride, phosphate, phosphonate, Phosphite, thiol, alcohol and / or isocyanate groups. The acid, Acid ester and acid chloride groups can z. As of carboxylic acids, phosphoric acids, phosphonic acids or sulphonic acids.

The backbone can be linear, branched, cyclic, dendritic and / or hyperbranched ("Hyperbranched") be constructed. The backbone may be a monomeric, oligomeric or polymeric structure. The chemical structure of the backbone is composed of aliphatic, alicyclic, heterocyclic, aromatic and / or heteroaromatic segments. Within the aliphatic, alicyclic, heterocyclic, aromatic and / or heteroaromatic segments, one or more functional groups may be included, e.g. B. -O-, -S-, -SO-, -SO ₂ -, -NR ¹ -, -PR ¹ -, -P (OR ¹ ) -, -POR ¹ -, -PO (OR ¹ ) -, -O-PO (OR ¹ ) -O-, -CO-, -CO ₂ -, O-CO-O-, -COS-, -CS ₂ -, -C = N-, -N = C = N- , -CO (NR ¹ ) -, O-CO-NR ¹ -, -NR ¹ -CO-NR ² -, -SiR ¹ R ² - and / or -SiR ¹ R ² -O-, wherein R ¹ = H or any organic radical, preferably an unsubstituted or substituted alkyl or aryl radical R ² = H or any organic radical, preferably an unsubstituted or substituted alkyl or aryl radical; identical or different from R ¹ .

are contain aliphatic segments in the backbone, so are these are preferably substituted (eg halogenated) and unsubstituted Alkyl and alkenyl compounds, ethers, esters, carbonates, urethanes, Derived polyethers, polyesters, polycarbonates and polyurethanes.

are contain alicyclic segments in the backbone, so are these are preferably substituted (eg halogenated) and unsubstituted Cycloalkanes (such as cyclohexane and its derivatives), spiranes (such as spiro [3.3] heptane) and bi- and polycyclic hydrocarbons (such as Decalin, Norbornane, Norcaran, Pinan, Adamantan, Twistan and Diamantane).

are heterocyclic segments contained in the backbone, so are these are preferably substituted (eg halogenated) and unsubstituted Derived from cyclodextrins, morpholines and Iminooxadiazindionen.

are contain aromatic segments in the backbone, so are these are preferably substituted (eg halogenated) and unsubstituted Benzene (such as benzene, toluene, phenol, aniline and biphenyl) and fused aromatic ring systems (such as indene, fluorene, Naphthalene, acenaphthene, anthracene, phenanthrene, naphthalene, pyrene and Chrysen).

are contain heteroaromatic segments in the backbone, so these are preferably of substituted (eg halogenated) and unsubstituted pyrroles, furans, thiophenes, indoles, benzofurans, Benzothiophenes, dibenzofurans, dibenzothiophenes, pyrazoles, imidazoles, Pyridines, pyrans, thiopyrans and quinolines derived.

When organic phase can also be a liquid crystalline compound or a mixture of several compounds, of which at least one is liquid crystalline, can be used that radically and / or cationic and / or anionic and / or ring-opening polymerizable groups and / or groups which cure via a condensation and / or addition reaction and / or over allow an acid-base reaction contains.

A Another preferred option is the use of a fluoride ion-releasing Compound or a mixture of several compounds, of which can release at least one fluoride ion, as an organic binder, additionally free-radical and / or cationic and / or anionic and / or ring-opening polymerizable groups and / or groups that have a cure over one Condensation and / or addition reaction and / or over allow an acid-base reaction contains.

Acrylates, methacrylates, acrylamides, methacrylamides, vinyl ethers, epoxides, oxetanes, spiroorthocarbonates, spiroorthoesters, bicyclic orthoesters, bicyclic monolactones, bicyclic bis-lactones, cyclic carbonates, cyclic acetals, allylsulfides, vinylcyclopropanes, organic phosphates, organic phosphonates, organic Phosphites or a combination of these compounds used. The generality not limiting are listed below some examples:
Methyl (meth) acrylate, ethyl (meth) acrylate, n- or i-propyl (meth) acrylate, n-, i- or tert-butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, phosphoric acid esters of hydroxyethyl (meth) acrylate or hydroxypropyl (meth) acrylate, (meth) acrylic acid, malonic acid mono- (meth) acrylate ester, succinic mono- (meth) acrylate ester, maleic mono (meth) acrylate ester, glycerin (meth) acrylate, glycerol (meth) acrylate ester, glycerol di (meth) acrylate, glycerol di (meth) acrylate ester (such as. Glycerol di (meth) acrylate succinate),
4- (meth) acryloyloxyethyltrimellitic acid, bis-4,6- or bis-2,5- (meth) acryloyloxyethyltrimellitic acid, 2- (((alkylamino) carbonyl) oxy) ethyl (meth) acrylates, allyl (meth) acrylate, Butanediol di (meth) acrylate, hexanediol di (meth) acrylate, decanediol di (meth) acrylate, dodecanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di ( meth) acrylates, glycerol di (meth) acrylate, glycerol propoxytri (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethoxylated and / or propoxylated trimethylolpropane tri (meth) acrylates, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A di (meth) acrylate, ethoxylated and / or propoxylated bisphenol A di (meth) acrylates, 2, 2-bis-4- (3- (meth) acryloxy-2-hydroxy-propoxy) -phenylpropane and compounds derived therefrom, chloro- and bromophosphoric acid esters of bisphenol A-glycidyl (meth) acrylate, urethane (meth) acrylates (such as B. 7,7,9-trimethyl-4,13-dioxo-3,14-dioxa-5,12-diazahexadecane-1,16-dioxy-dimethacrylate), polyester urethane (meth) acrylates, polyester (meth) acrylates, Polycarbonate (meth) acrylates, polyamide (meth) acrylates, polyimide (meth) acrylates, phosphazene (meth) acrylates and siloxane (meth) acrylates; Ethyl vinyl ether, n- or i-propyl vinyl ether, n-, i- or tert-butyl vinyl ether, hexyl vinyl ether, octyl vinyl ether, cyclohexyl vinyl ether, cyclohexyl-3,4-epoxy-1-methyl vinyl ether, dimethanol cyclohexyl monovinyl ether, 1,4-dimethanol cyclohexyl divinyl ether, propanediol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, octanediol divinyl ether, decanediol vinyl ether, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, triethylene glycol monovinyl ether mono (meth) acrylic acid ester, polyethylene glycol divinyl ether, tripropylene glycol divinyl ether, glycerol trivinyl ether, pentaerythritol tetravinyl ether, 7,7,9-trimethyl-4,13- dioxo-3,14-dioxa-5,12-diazahexadecane-1,16-dioxydivinyl ethers, bisphenol A divinyl ethers, ethoxylated and / or propoxylated bisphenol A divinyl ethers, polyester vinyl ethers, polycarbonate vinyl ethers, polyacrylate vinyl ethers, polyvinyl vinyl ethers, polyimide vinyl ethers, polyurethane vinyl ethers, Phosphazenovinyl ether and siloxane vinyl ether; Alkyl glycidyl ethers, glycidol, glycidyl (meth) acrylate, dipentene dioxide, 1,2-epoxyhexadecane, bis (3,4-epoxycyclohexyl) adipate, vinylcyclohexene oxides, vinylcyclohexene dioxides, epoxycyclohexanecarboxylates (such as 3,4-epoxycyclohexylmethyl-3,4- epoxycyclohexene carboxylate), butanediol diglycidyl ether, hexanediol diglycidyl ether, dodecanediol diglycidyl ether, diglycidyl ether of polyethylene glycols and polypropylene glycols, diglycidyl ethers of substituted (eg halogenated) and unsubstituted bisphenols (such as bisphenol A, bisphenol C and bisphenol F), Resorcinol diglycidyl ethers, trimethylolethane triglycidyl ethers, trimethylolpropane triglycidyl ethers, polybutadiene polyepoxides, polyester epoxies, polycarbonate epoxies, polyacrylate epoxies, polyamide epoxies, polyimide epoxies, polyurethane epoxies, phosphazene epoxies, and siloxane epoxies; 3,3-disubstituted oxetanes and dioxetanes (such as 3-ethyl-3- (2-hydroxyethyl) oxetane); (Trans / trans) -2,3,8,9-di (tetramethylene) -1,5,7,11-tetraoxaspira- [5.5] undecane; substituted 1,3-dioxolanes (such as 2-phenyl-4-methylene-1,3-dioxolane); difunctional 6-methylene-1,4-dithiepane and the reaction products of nucleophilic (meth) acrylates such. B. 2-hydroxyethyl (meth) acrylate or glycerol (meth) acrylate esters with reactive phosphoric acid, phosphonic acid or phosphinic acid derivatives such. B. P ₂ O ₅ , POCl ₃ or PCl ₃ . For curing the dental material according to the invention, preferably one initiator or a plurality of initiators and optionally one coinitiator or several coinitiators are incorporated into the dental material according to the invention. In this case, initiator or initiators and coinitiator or coinitiators may be contained together in one component and / or separately in two or more components. The dental material according to the invention can thus be cured thermally, chemically, photochemically, ie by irradiation with UV and / or visible light, and / or by reaction with the oral and / or atmospheric moisture.

The here usable initiators can, for. B. photoinitiators be. These are characterized by their absorption of light in the ultraviolet or visible range (wavelength range from 300 nm to 700 nm, preferably from 350 nm to 600 nm, and especially preferably from 380 nm to 500 nm) and optionally by the additional Reaction with one or more coinitiators curing of the material. Preference is given here phosphine oxides, Bezoin ethers, benzil ketals, acetophenones, benzophenones, thioxanthones, Bisimidazoles, metallocenes, fluorones, α-dicarbonyl compounds, Aryldiazonium salts, arylsulfonium salts, aryliodonium salts, ferrocenium salts, Phenylphosphoniumsalze or a mixture of these compounds used.

Especially preference is given to diphenyl-2,4,6-trimethylbenzoylphosphine oxide, benzoin, Benzoin alkyl ethers, benzil dialkyl ketals, α-hydroxy acetophenone, Dialkoxyacetophenones, α-aminoacetophenones, i-propylthioxanthone, Camphorquinone, phenylpropanedione, 5,7-diiodo-3-butoxy-6-fluorone, (eta-6-cumene) (eta-5-cyclopentadienyl) iron hexafluorophosphate, (eta-6-cumene) (eta-5-cyclopentadienyl) iron tetrafluoroborate, (eta-6-cumene) (eta-5-cyclopentadienyl) iron hexafluoroantimonate, substituted diaryliodonium salts, triarylsulfonium salts or a Mixture of these compounds used.

When Co-initiators for a photochemical curing tertiary amines, borates, organic phosphites, Diaryliodonium compounds, thioxanthones, xanthenes, fluorenes, fluorones, α-dicarbonyl compounds, condensed polyaromatics or a mixture of these compounds used. Particular preference is given to N, N-dimethyl-p-toluidine, N, N-dialkyl-alkyl-anilines, N, N-dihydroxyethyl-p-toluidine, 2-ethylhexyl-p- (dimethyl-amino) -benzoate, Butyrylcholine-triphenylbutyl borate or a mixture of these compounds used.

As initiators and so-called thermal initiators can be used by the Auf Taking thermal energy at elevated temperature can cause the material to cure. In this case, preference is given to using inorganic and / or organic peroxides, inorganic and / or organic hydroperoxides, α, α'-azobis (isobutyroethyl ester), α, α'-azobis (isobutyronitrile), benzopinacols or a mixture of these compounds. Particular preference is given to diacyl peroxides such as. As benzoyl peroxide or lauroyl peroxide, cumene hydroperoxide, benzopinacol, 2,2'-dimethylbenzopinacol or a mixture of these compounds used.

For a chemical curing at room temperature i. a. uses a redox initiator system consisting of one or more Initiators and serving as an activator coinitiator or coinitiators consists. As already mentioned for reasons storage stability initiator or initiator and coinitiator or coinitiators in spatially separated parts incorporated the dental material according to the invention, d. H. it is a multicomponent, preferably a two-component Material in front. As initiator or initiators are preferably inorganic and / or organic peroxides, inorganic and / or organic hydroperoxides, CH-acidic compounds such as barbituric acid derivatives and their salts, malonylsulfamides, protic acids, Lewis or Broensted acids or compounds which are such acids release, carbenium ion donors such. As methyl triflate or Triethyl perchlorate or a mixture of these compounds and preferably tertiary as coinitiator or as coinitiators Amines, heavy metal compounds, in particular compounds of the 8th and the 9th group of the periodic table ("iron and copper group"), compounds with ionically bonded halogens or pseudohalogens such. B. quaternary ammonium halides, weak Broenstedt acids such as As alcohols and water or a mixture of these compounds used.

The chemical elements with atomic numbers from 21 to 30, 39 to 48, 57 to 80 and 89 to 112 of the Periodic Table are becoming common referred to as transition elements. Because these elements are all Metals are in the present application also the term transition metals used.

In The dental material according to the invention can also every conceivable combination of the initiators described above and Co-initiators may be included. An example of this is so-called dual-curing dental materials containing both photoinitiators and optionally the corresponding coinitiators for a photochemical curing as well as initiators and corresponding Co-initiators for chemical curing at room temperature contain.

• – Herstellung von 0-dimensionalen Nanodiamanten durch Reaktion in der Gasphase (Niederdrucksynthese im Microwellen Plasma Reaktor durch Umsetzung von CH₂Cl₂/O₂-Gemischen: M. Frenklach et al., J. Appl. Phys. 66 [1989] S. 395–399 ; ggf unter Zusatz von B₂H₂: M. Frenklach et al., Appl. Phys. Lett. 59 [1991] S. 546–548 );
• – Herstellung von Detonationsnanodiamanten (UDD = ultradispersed diamond entsteht dadurch, dass Sprengstoffe unter Luftabschluß zur Detonation gebracht werden und aus deren Bestandteilen unter hohem Druck Nanodiamant entsteht);
• – Herstellung von Nanodiamanten durch Schockwellensynthese (es wird eine Schockwelle erzeugt, die dann auf Kohlenstofftargets unter Bildung von Nanodiamant einwirkt: Y. Q. Zhul et al., Chem. Phys. Lett. 287 [1998] S. 689–693 );
• – Herstellung von Nanodiamanten durch Einwirkung von Strahlung auf Kohlenstoffspezies (Einwirkung von CVD Plasma von CH₄/H₂: Y. Lifshitz et al.: Science 297 [2002] S. 1531–1533 oder von Ionenstrahlung unter Verwendung von Kohlenwasserstoffen, Wasserstoff oder Argon: H. Yusa, Diam. Relat. Mat. 11 [2002] S. 87–91 auf amorphe Kohlenstoffmatrixes an Siliziumoberflächen);
• – Herstellung von Nanodiamanten durch Ionenbombardment von SiC (Siliziumcarbid) mit C (60 keV, 900°C: F. Li et al., Appl. Phys. Lett. 77 [200] S. 3161–3163 ) oder von fein verteilten polykristallinen Graphit mit Krypton-Ionen (20°C, 350 MeV: T. L. Daulton et al., Nicl. Inst. Meth. Phys. Res. B175 [2001] S. 12–20 );
• – Herstellung von Nanodiamanten durch Umwandlung von Kohlenstoffspezies im Elektronenstrahl (1,2 MeV, 900 K: P. Banhart et al., Nature 382 [1996] S. 433 );
• – Herstellung von Nanodiamanten durch aus synthetisch hergestellten oder natürlich vorkommenden gröberen Diamantpulvern gegebenenfalls nach Mahlurig ausgesiebt, durch Klassierung oder andere geeignete Trennverfahren abgetrennt; und
• – Diamantnanorods (durch selektives Ätzen von CVD Diamantfilmen: E.-S. Baik et al. J. Mat. Res. 15 [200] S. 923–926 ) und Nanofasern (durch Laserabtragung von UDD-Pellets: A. Koscheev, Ximia zizn 1 [1999] S. 14–16 ).

The nanodiamonds usually have an average primary particle diameter of 0.5-100 nm, preferably 1-60 nm, more preferably 1-40 nm, more preferably 1-20 nm, more preferably 2-8 nm, further preferably 3-6 nm , more preferably 3.5-5.5 nm. Such nanodiamonds can be obtained by various methods known from the prior art and are described in detail, for example OA Shenderova; VV Zhirnov; DW Brenner: "Carbon Nanostructures", Critical Reviews in Solid State and Materials Sciences 27 (3/4) [2002] p. 227-356, in particular pages 266 ff , or in A. Krüger: New Carbon Materials - An Introduction; Vieweg & Teubner 2007 or in the aforementioned WO-A-2005/097045 , By way of example, reference is made to the production of nanodiamonds in the following ways:

• Production of 0-dimensional nanodiamonds by reaction in the gas phase (low-pressure synthesis in the microwave plasma reactor by reaction of CH ₂ Cl ₂ / O ₂ mixtures: M. Frenklach et al., J. Appl. Phys. 66 [1989] p. 395-399 ; if necessary with the addition of B ₂ H ₂ : M. Frenklach et al., Appl. Phys. Lett. 59 [1991] p. 546-548 );
• - Production of detonation nanodiamonds (UDD = ultradispersed diamond is caused by detonating explosives under exclusion of air and from components of which under high pressure nanodiamant is formed);
• - Production of nanodiamonds by shock wave synthesis (a shock wave is generated, which then acts on carbon targets to form nanodiamond: YQ Zhul et al., Chem. Phys. Lett. 287 [1998] pp. 689-693 );
• Production of nanodiamonds by action of radiation on carbon species (action of CVD plasma of CH ₄ / H ₂ : Y. Lifshitz et al .: Science 297 [2002] pp. 1531-1533 or ionic radiation using hydrocarbons, hydrogen or argon: H. Yusa, Diam. Relat. Mat. 11 [2002] pp. 87-91 on amorphous carbon matrix on silicon surfaces);
• - Production of nanodiamonds by ion bombardment of SiC (silicon carbide) with C (60 keV, 900 ° C: Li, F. et al., Appl. Phys. Lett. 77 [200] pp. 3161-3163 ) or finely divided polycrystalline graphite with krypton ions (20 ° C., 350 MeV: TL Daulton et al., Nic. Inst. Meth. Phys. Res. B175 [2001] p. 12-20 );
• Preparation of Nanodiamonds by Conversion of Carbon Species in the Electron Beam (1.2 MeV, 900 K: Banhart, P. et al., Nature 382 [1996] p. 433 );
• - Production of nanodiamonds by sieved from synthetically produced or naturally occurring coarser diamond powders optionally after Mahlurig, separated by classification or other suitable separation methods; and
• Diamond nanorods (by selective etching of CVD diamond films): IT. Baik et al. J. Mat. Res. 15 [200] p. 923-926 ) and nanofibers (by laser ablation of UDD pellets: A. Koscheev, Ximia zizn 1 [1999] p. 14-16 ).

As already mentioned, more detailed information on the processes mentioned and on those which lead to polycrystalline Naondiamantpulvern, for example in in OA Shenderova et al., "Carbon Nanostructures", Critical Reviews in Solid State and Materials Sciences 27 (3/4) [2002] p. 249ff ,

The Production of transparent or translucent nanodiamond powder can be advantageous if the dental materials produced therefrom to be translucent. For example, it may be desirable be that nanodiamond containing Fissurenversiegeler translucent are not as such visually on the tooth surface to be perceived. There are also translucent fillers required to high-transparency materials, for example make the enamel substitute or materials in very bright colors to be able to.

The Dental material according to the invention may be in the inorganic Phase contain dental usual fillers. at the fillers used in the invention they are preferably nano- and / or microscale fillers, preferably glass powder, glass ceramic powder, metal, metalloid or mixed metal oxides, silicate, nitride, sulfate, titanate, zirconate, Stannate, woframate, silica compounds or a mixture from these compounds or spherical fillers, Quartz powder or a mixture of these powders or filled or unfilled splintered polymers and / or bead polymers.

at the nano- or microscale used according to the invention Fillers are particularly preferably dental glasses, Silica, alumina, zirconia, titania, zinc oxide, Tin dioxide, cerium oxide, aluminum-silicon oxides, silicon-zinc oxides, Silicon-zirconium oxides, iron oxides and their mixtures with silicon dioxide, Indium oxides and their mixtures with silicon dioxide and / or tin dioxide, Boron nitride, strontium sulfate, barium sulfate, strontium titanate, barium titanate, Sodium zirconate, potassium zirconate, magnesium zirconate, calcium zirconate, Strontium zirconate, barium zirconate, sodium tungstate, potassium tungstate, Magnesium tungstate, calcium tungstate, strontium tungstate and / or Barium tungstate.

Of the Filler may be a surface-modified filler, preferably an organic surface-modified filler be. The filler can after its surface modification, for example, a silanization, on its surface functional groups, for example reactive (meth) acrylate groups possess, with the monomers chemically, preferably radically, can react and / or have a high affinity to the polymer matrix formed from the monomers.

The Dental material according to the invention can be used for adjustment certain properties additionally called additives or modifiers. Not restricting the general public Below are some examples: inorganic and / or organic color pigments or dyes, stabilizers (such as substituted and unsubstituted hydroxyaromatics, tinuvines, terpinene, Phenothiazine, HALS - Hindered Amine Light Stabilizers - and / or Heavy metal scavengers such as EDTA), plasticizers (such as polyethylene glycols, Polypropylene glycols, unsaturated polyesters, phthalates, Adipate, sebacate, phosphoric acid ester, phosphonic acid ester and / or citric acid esters), ion-emitting substances, especially those which release fluoride ions, such as. B. ion-releasing Dental glasses (reactive glasses), sodium fluoride, Potassium fluoride, yttrium fluoride, ytterbium fluoride and / or quaternary Ammonium fluorides), bactericidal or antibiotic substances (such as chlorhexidine, pyridinium salts, penicillins, tetracyclines, Chloramphenicol, antibacterial macrolides and / or polypeptide antibiotics) and / or solvents (such as, for example, water, acetone, ethanol, i-propanol, butanone and / or ethyl acetate).

The Dental material according to the invention can be used for Prosthetic, conservative and preventive dentistry and used in the dental laboratory. Without claim to Completeness are representative of some examples called: filling material, underfilling material, Buttstock material, fastening material, provisional and permanent Crown and bridge material, bonding materials, dental technology Material for the production of inlays, onlays, veneers, artificial Teeth, model materials and fissure and root canal sealing material.

The invention will be described below without limiting the generality by means of Ausführungsbei play explained.

Example 1: Characterization of the used Nano diamond

In The following examples were Nanodiamantpulver Fa. New Metals And Chemicals Corporation, Ltd. (Kyobashi TD, Kyobashi, Chuo-Ku, Tokyo), wherein the nanodiamond powder in the examples 2-4 and 5-6 each from the same delivery batch come.

The diamond powder was prepared by the detonation process from 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitro-1,3,5-triazinane (hexogen) and has a spherical to ellipsoidal particle shape with a primary particle size between 3 nm and 10 nm, which was determined by X-ray diffraction (X-ray diffraction or XRD), dynamic light scattering and high resolution transmission electron microscopy (HRTEM). The specific surface area is between 278 m ² / g and 335 m ² / g. The average chemical composition determined by elemental analysis is 91% carbon, 2% hydrogen, 5% oxygen, and 2% nitrogen. Electron Paramagnetic Resonance (EPR) spectroscopy studies show that most of the nitrogen is incorporated into the diamond lattice and the oxygen and hydrogen, along with the proportions of nitrogen as oxygen-, nitrogen-, and hydrogen-containing functional groups on the surface of the diamond crystallites (eg: -OH, -C = O, -COOH, -COC, -CN according to the manufacturer's instructions). The density of the nanodiamond powder is between 3.05 and 3.12 g / ml.

Example 2: Treatment of nanodiamond powder with 37% hydrochloric acid

Around the effect of acid on the content of various transition metals and other ions on the nanodiamond powder according to example 1, nanodiamant powder was mixed with concentrated hydrochloric acid purified and the content of transition metal and other Ions compared before and after cleaning.

It 100 g of hydrochloric acid were added to 20 g of nanodiamond powder and overnight at room temperature with stirring (3 hours) with conc. HCl treated. Subsequently was the hydrochloric acid separated. Since the separated hydrochloric acid still had a yellowish color, which is an indication of the Possibility of dissolving out further ions the HCl treatment was still 2 × with stirring times repeated for 3 hours. Subsequently, the diamond powder became washed to neutrality with water, then dried and for the preparation of a test composite according to Example 8 used.

The results of the treatment are summarized in the table below, in which the content of the various transition metal and other ions in the nanodiamond powder prepared by the explosion process [determined by atomic emission spectroscopy (AAS), ICP screening, DIN EN ISO 11885-E 22 ] are compared before and after HCl purification. The values of the HCl-untreated sample are mean values of three individual values. element Content [ppm] untreated HCl-treated barium 440 7.2 lead 61 1.7 chrome 4.3 0.6 iron 690 48 potassium 15.5 8.8 copper 9.5 0.8 magnesium 13.3 6.2 manganese 113.3 0.5 nickel 3.4 2.3 strontium 8.9 0.6 tin 8.6 2.1

The AAS determination after the HCl treatment shows a depletion of the transition metals Ei sen, manganese, chromium, nickel and copper. Particularly clear is the depletion of iron, manganese and copper. Furthermore, the content of barium and especially lead (from 61 ppm to 1.7 ppm) decreases. Thus, the filler harmless from the toxicological side.

Example 3: Kinetics of depletion of various transition metal and other ions when treating the diamond powder at 37% HCl

Around the effect of acid on the content of various transition metals and other ions of nanodiamond powder according to example 1 depending on the HCl treatment time, Nanodiamant powder was purified with concentrated hydrochloric acid and the content of transition metal and other ions the treatment with the after 30 min, 60 min, 90 min, 120 min and 150 min HCl treatment time compared.

It 50 g of nanodiamond in 325 g of hydrochloric acid (37%) were added 30 min stirred at room temperature. Subsequently was the acid is filtered off and the nanodiamond is filtered 2 times washed with distilled water. A sample of 3 g was removed dried and by means of atomic emission spectroscopy the elemental composition certainly. This process was for the further HCl treatment times from 60 min, 90 min, 120 min and 150 min, d. H. a total of 5 × performed. After the 5th extraction (150 min), the nanodiamond was multiply washed free of chloride with water (test with silver nitrate), then dried and for the preparation of a test composite used according to Example 8.

The results of the atomic emission spectroscopy measurements [ICP screening, DIN EN ISO 11885-E 22 ] are summarized in the following table, where the values of the HCl-untreated sample are averages of three individual values. element Content [ppm] untreated HCl-treated 30 min 60 min 90 min 120 min 150 min barium 440 180 79 41 13 1.8 lead 61 24 10 4.4 2.1 0.46 chrome 2.8 0.75 0.54 0.37 0.42 0.48 iron 690 270 140 79 52 46 potassium 15.5 37 12 14 8.8 11 copper 9.5 6.1 4.9 3.7 2.3 2.5 magnesium 13.3 7 7.5 6.3 6.3 5.8 manganese 113.3 27 7.3 2.3 1.2 0.8 nickel 3.4 0.53 0.39 0.27 0.30 0.44 strontium 8.9 2.4 1.0 0.9 0.6 0.6 tin 8.6 6.3 3.1 1.6 1.2 1.0

The AAS determination shows that the levels of copper, nickel and chromium already after an HCl treatment of 90 min. in the lower single digits ppm range can be lowered. That also applies to the higher-concentration elements manganese and lead. Also is the content over the investigated HCl treatment period significantly lowered in iron, but is at 46 ppm after 150 min still comparatively high.

Example 4: Treatment of nanodiamond powder with the chelating agent Komplexon II (ethylenediamine tetraacetic acid)

Around the effect of chelating agents on the content of various transition metals and other ions on the nanodiamond powder according to example 1, nanodiamant powder with the chelating agent was investigated Komplexon III (EDTA-disodium salt dihydrate) and the content of transition metal and other ions before and after Cleaning compared with each other.

There were 60 g of nanodiamant according to Example 1 4 hours at room temperature with 330 g of 0.1 m Lö solution of the EDTA disodium salt dihydrate with stirring. The solution was then filtered off and the solid was washed with distilled water (7 ×) until no more discoloration of the washing water was discernible. The sample was dried and the elemental composition was analyzed by atomic emission spectroscopy (ICP screening, DIN EN ISO 11885-E 22 ) for the elements iron manganese, lead, copper and chromium.

The results are summarized in the table below, where the values of the HCl-untreated sample are averages of three individual values. element Content [ppm] untreated treated with EDTA iron 690 510 manganese 113.3 26 lead 61 10 copper 9.5 7 chrome 4.3 2.8

Example 5: Kinetics of depletion of various transition metal and other ions in treating the nanodiamond powder with the Chelating agent complexone III (disodium ethylenediaminetetraacetic acid)

Around the effect of chelating agents on the content of various transition metals and other ions of nanodiamond powder according to example 1 depending on the treatment time, was nanodiamant powder with the chelating agent Komplexon III (disodium ethylenediamine tetraacetic acid) purified and the content of transition metal and other Ions before treatment with after 30 min, 60 min, 90 min, 120 min and 150 min chelator treatment time compared.

It were 60 g of nanodiamond in 330 g of 0.1 M disodium ethylenediaminetetraacetic acid dihydrate Stirred for 30 min at room temperature. Subsequently The solution was filtered off and the nanodiamond 2 × with washed with distilled water. A sample of 3 g was removed dried and by means of atomic emission spectroscopy the elemental composition certainly. This process was used for the further chelating treatment times from 60 min, 90 min 120 min and 150 min, d. H. a total of 5 × performed. After the 5th extraction (150 min), the nanodiamond was multiply washed free of chloride with water (test with silver nitrate), then dried and for the preparation of a test composite used according to Example 8.

The results of the atomic emission spectroscopy measurements [ICP screening, DIN EN ISO 11885-E 22 ] are summarized in the following table, where the values of the untreated sample are averages of three individual values. element Content [ppm] untreated treated with di-Na-EDTA solution 30 min 60 min 90 min 120 min 150 min barium 490 240 140 110 83 74 lead 58 23 6.4 2.4 1.1 0.61 chrome 3.4 2.5 2.3 3.0 2.0 2.1 iron 710 560 350 280 300 240 potassium 17 19 25 20 12 13 copper 9.0 7.9 7.1 7.1 4.6 5.9 magnesium 15 9.3 11 9.7 7.8 6.9 manganese 120 76 36 25 18 13 nickel 1.9 1.5 1.2 1.6 1.2 1.1 strontium 9.6 3.7 1.3 0.86 0.63 <0.5 tin 10 10 8.6 11 8.6 8.1

The AAS determination according to Examples 4 and 5 shows that in addition to the treatment with an acid according to Examples 2-3 also an effective depletion, in particular of the elements copper, Ni ckel, chromium, manganese, iron and lead is possible by treatment of the nanodiamond powder with chelating agents.

at the opposite to the acid treatment (Examples 2-3) apparently lower depletion efficiency of the used Chelating is to take into account that the chelating solutions were significantly less concentrated (eg, the 0.1 m = about 3.7 Disodium ethylene diamine tetra-acetic acid solution) as the concentrated acid solution in the examples 2-3 (37% HCl solution).

Of Further, the nanodiamond samples treated in Examples 4 and 5 became for the production of test composites according to example 8 used.

Example 6 Depletion of Various Transition Metal and other ions by combining a thermal treatment with an acid treatment of the nanodiamond powder

The Combined thermal and acid treatment of nanodiamond powder based on the idea of containing foreign ions as well as foreign phases on the one hand, to make it more acid-soluble or even better first to transform into an acid-soluble form and second, by burning off at the nanodiamond surface graphites the accessibility of the foreign ions or to improve foreign phases for the acid.

Example 6a

First was therefore 60 g of nanodiamond in the muffle furnace for 1 hour annealed at 430 ° C. The occurring loss of mass was 8.41%. Subsequently, the annealed nanodiamond powder was transferred to a round bottom flask and 37% with 30 min Hydrochloric acid refluxed. After that the acid was separated by means of a frit. This The process was repeated once. Subsequently, the Nanodiamant powder washed with water free of chloride, then dried at 110 ° C and to produce a test composite used according to Example 8.

The results of the atomic emission spectroscopy measurements [ICP screening, DIN EN ISO 11885-E 22 ] for this experiment [thermal / HCl (2 ×)] are summarized in column 4 in the following table and are concentrated to the values of the untreated nanodiamond sample (mean values of three individual values) shown in column 2 and the values of the 5-fold extraction shown in column 3 Hydrochloric acid from Example 3 set in comparison.

Example 6b

In in a further experiment, the aforementioned experimental set-up [thermal / HCl (2 ×)] with the 5-fold extraction according to Example 3 [HCl (5 ×)] combined [HCl (5x) / thermal / HCl (2x)].

To 90 g of nanodiamond powder in 450 g of conc. HCl boiled for 30 min at reflux. After 30 minutes, the hydrochloric acid was filtered off. After total 5 times cooking, the nanodiamond was washed free of chloride with water and dried at 110 ° C. Subsequently, the Powder in a muffle furnace preheated to 425 ° C for 1 hour annealed. After cooling, the powder became again Boiled twice with concentrated hydrochloric acid, then washed free of chloride with water, then at 110 ° C. dried and for the preparation of a test composite according to Example 8 used.

The results of the atomic emission spectroscopy measurements [ICP screening, DIN EN ISO 11885-E 22 ] for this further experiment [HCl (5 ×)] combined [HCl (5 ×) / thermal / HCl (2 ×)] are summarized in column 5 of the following table. element Content [ppm] untreated treated HCl (5X) thermal / HCl (2 x) HCl (5 x) / thermal / HCl (2 x) barium 490 1.8 2.3 2.2 lead 58 0.46 0.96 <1 chrome 3.4 0.48 1.7 2.9 iron 710 46 140 13 potassium 17 11 8.5 17 copper 9.0 2.5 0.91 <1 magnesium 15 5.8 7.7 11 manganese 120 0.8 2.8 <1 nickel 1.9 0.44 0.54 3.8 strontium 9.6 0.6 <0.5 <1 tin 10 1.0 2.3 3.6

Out The tabular comparison shows that after 5 treatments with concentrated hydrochloric acid a significant depletion of transition metal ions, as well as other ions, for example lead ions, in nanodiamond powder is achievable (column 3). In contrast leads the thermal treatment in combination with subsequent 2-fold HCl extraction of the nanodiamond powder (column 4) to partly lower Depletion values, for example for iron. combined But if you use both treatments together, the results are very low Contents in the nanodiamond powder, in particular iron (column 5).

Example 7: Characterization of the Example 8 base resin used in the composites

As a base resin for the preparation of the composites according to Example 8, a resin mixture was used with the following components:
31.73% by weight Until GMA,
31.73% by weight of ethoxylated bisphenol A dimethacrylate,
18.23% by weight TEDMA, triethylene glycol dimethacrylate,
18.23% by weight of TMPTMA, trimethylolpropane trimethacrylate,
0.08 wt .-% 2,6-di-tert. Butyl-4-methylphenol.

Example 8: Preparation and Examination the storage stability of initiator pastes

• 1: mit unbehandelten Nanodiamant gemäß Beispiel 1;
• 2: mit Nanodiamant gemäß Beispiel 2 [HCl(3×)];
• 3: mit Nanodiamant gemäß Beispiel 3 [HCl(5×)];
• 4: mit Nanodiamant gemäß Beispiel 4 [Chelatbildner Komplexon II (EDTA)];
• 5: mit Nanodiamant gemäß Beispiel 5 [Chelatbildner Komplexon III Di-Na-EDTA(5×)];
• 6a: mit Nanodiamant gemäß Beispiel 6a [thermisch/HCl(2×)]; und
• 6b: mit Nanodiamant gemäß Beispiel 6b [HCl(5×)/thermisch/HCl(2×)];

in folgender Art und Weise hergestellt:
Zunächst wurde das vorgenannte Nanodiamantpulver in ein Grundharz gemäß Beispiel 7 eingearbeitet. Die erhaltene Nanodiamantsuspension wurde anschließend mit dem Initiator Dibenzoylperoxid und weiteren Füllstoffen zu einem Komposit verarbeitet. Im Einzelnen:
Zur Herstellung der Komposite wurde zunächst das Nanodiamantpulver (21,007 Gew.-%) mit den weiteren Komponenten in das Grundharz der Basispasten („B” in der nachfolgenden Tabelle) und Initatorpasten („I” in den nachfolgenden Tabellen), wie in der nachfolgenden Tabelle im Einzelnen aufgeführt, eindispergiert. Dazu wurde ein Dispergierrad mit einem Durchmesser von 40 mm verwendet. Das flüssige Medium wurde in einem mit Wasser gekühlten (doppelwandigen) Edelstahlgefäß (T < 40°C, ⌀ 79 mm) vorgelegt und das Nanodiamantpulver portionsweise zugegeben. Die Gesamtdispergierzeit betrug 4 Stunden. Dabei wurde zunächst bei Drehzahlen von 5000–6000 1/min (10,5 m/s–12,6 m/s) das Nanodiamantpulver eingearbeitet (15–30 min). Anschließend wurde die Drehzahl auf 10000 1/min (21 m/s) gesteigert. Mit Zunahme der Viskosität der Nanodispersion wurde die Drehzahl so angepasst, dass ein Freilauf der Dispergierscheibe vermieden wurde.It became the following seven nanodiamond composites

• 1: with untreated nanodiamond according to Example 1;
• 2: with nanodiamant according to Example 2 [HCl (3 ×)];
• 3: with nanodiamant according to Example 3 [HCl (5 ×)];
• 4: with nanodiamant according to Example 4 [chelating agent complex II (EDTA)];
• 5: with nanodiamant according to Example 5 [chelating agent Komplexon III di-Na-EDTA (5 ×)];
• 6a: with nanodiamant according to Example 6a [thermal / HCl (2 ×)]; and
• 6b: with nanodiamant according to Example 6b [HCl (5 ×) / thermal / HCl (2 ×)];

made in the following manner:
First, the aforementioned nanodiamant powder was incorporated into a base resin according to Example 7. The resulting nanodiamond suspension was then processed into a composite with the initiator dibenzoyl peroxide and further fillers. In detail:
To prepare the composites, first the nanodiamant powder (21.007% by weight) with the other components in the base resin of the base pastes ("B" in the table below) and initiator pastes ("I" in the following tables), as in the following table listed in detail, dispersed. For this purpose, a dispersing wheel with a diameter of 40 mm was used. The liquid medium was placed in a water-cooled (double-walled) stainless steel vessel (T <40 ° C, ⌀ 79 mm) and the nanodiamond powder added in portions. The total dispersion time was 4 hours. Initially, the nanodiamant powder was incorporated at speeds of 5000-6000 1 / min (10.5 m / s-12.6 m / s) (15-30 min). Subsequently, the speed was increased to 10000 1 / min (21 m / s). With increase in the viscosity of the nanodispersion The speed was adjusted so that a free wheel of the dispersing disk was avoided.

Subsequently The nanodispersion was transferred to the container of a kneader and first incorporated the components of a starter system. After that was a small amount of Aerosil, which was the setting of certain Handling properties used, stirred. After all the dental glass and optionally further additives were incorporated. The filler content was measured so that flowable (flowable) composites resulted.

The following table shows the basic recipe of the composites. Component [% by weight] B I B + I base resin 63.16 61.38 62.27 nanodiamond 16,80 16.32 16.56 Aerosil Cab-O-Sil 1.92 1.92 1.92 Dental glass sil. 17.44 17.94 17.69 dibenzoyl - 0.46 0.23 N, N-bis-hydroxyethyl-p-toluidine 0.68 - 0.34 Alkenoic acid alkenyl esters - 1.98 0.99 Total content of nanoparticles 18.48 Gesamtfüllgrad 36.16 36.18 36.17

The determined storage stabilities for the initiator pastes of composites 1-5, 6a and 6b are as follows at room temperature: composites storage stability 1: with untreated nanodiamond according to Example 1; 2-3 hours 2: with nanodiamant according to Example 2 [HCl (3 ×)]; about 1 day 3: with nanodiamant according to Example 3 [HCl (5 ×)]; about 2 days 4: with nanodiamant according to Example 4 [chelating agent complex II (EDTA)]; about 6 hours 5: with nanodiamant according to Example 5 [chelating agent Komplexon III di-Na-EDTA (5 ×)]; about 2 days 6a: with nanodiamant according to Example 6a [thermal / HCl (2 ×)]; and about 1 week 6b: with nanodiamant according to Example 6b [HCl (5 ×) / thermal / HCl (2 ×)]. more than 5 months

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1913927 A [0002]
• - DE 975072 C [0006]
• WO 2005/097045 A [0046]

Cited non-patent literature

• - Ullmanns Encyclopaedia of Industrial Chemistry, 6th Edition, Volume 10, page 355 et seq. [0002]
• - G. Schwarzenbach: "The complexometric titration" 4th edition Stuttgart 1960 [0024]
• - OA Shenderova; VV Zhirnov; DW Brenner: "Carbon Nanostructures", Critical Reviews in Solid State and Materials Sciences 27 (3/4) [2002] p. 227-356, in particular pages 266 et seq. [0046]
• - A. Krüger: New carbon materials - An introduction; Vieweg & Teubner 2007 [0046]
• M. Frenklach et al., J. Appl. Phys. 66 [1989] p. 395-399 [0046]
• M. Frenklach et al., Appl. Phys. Lett. 59 [1991] p. 546-548 [0046]
• YQ Zhul et al., Chem. Phys. Lett. 287 [1998] p. 689-693 [0046]
• Y. Lifshitz et al .: Science 297 [2002] pp. 1531-1533 [0046]
• - H. Yusa, Diam. Relat. Mat. 11 [2002] p. 87-91 [0046]
• - F. Li et al., Appl. Phys. Lett. 77 [200] pp. 3161-3163 [0046]
• TL Daulton et al., Nic. Inst. Meth. Phys. Res. B175 [2001] p. 12-20 [0046]
• Banhart, P. et al., Nature 382 [1996], p. 433 [0046]
• - E.-S. Baik et al. J. Mat. Res. 15 [200] p. 923-926 [0046]
• - A. Koscheev, Ximia zizn 1 [1999] p. 14-16 [0046]
• OA Shenderova et al., "Carbon Nanostructures", Critical Reviews in Solid State and Materials Sciences 27 (3/4) [2002] p. 249ff [0047]
• - DIN EN ISO 11885-E 22 [0059]
• - DIN EN ISO 11885-E 22 [0063]
• - DIN EN ISO 11885-E 22 [0066]
• - DIN EN ISO 11885-E 22 [0070]
• - DIN EN ISO 11885-E 22 [0076]
• - DIN EN ISO 11885-E 22 [0079]

Claims (15)

Polymerizable, nanodiamond-containing dental material, obtainable by cleaning the nanodiamonds at least once with at least one acid and / or at least one organic Solvent and / or at least one chelating agent and Incorporation of the purified nanodiamonds into the dental material. Dental material according to claim 1, characterized it is a redox initiator system, preferably a redox initiator system with at least one initiator and / or at least one activator having serving co-initiator. Polymerizable dental material according to one of the preceding Claims, characterized in that the cleaning of Nanodiamonds to a depletion of - at least a transition metal ion, preferably selected from the group consisting of iron, chromium, manganese, copper and nickel and or - ions selected from the group consisting of lead, tin and barium leads. Dental material according to one of the preceding claims, characterized in that the nanodiamonds with an acid selected from the group consisting of - inorganic Acids, preferably selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid, - and organic acids, preferably selected from the group consisting of monocarboxylic acids, dicarboxylic acids, Tricarboxylic acids, multicarboxylic acids, polycarboxylic acids or derivatives of these acids, getting cleaned. Dental material according to one of the preceding claims, characterized in that the chelating agent under the name Complexed aminopolycarboxylic acids are, which form chelate complexes with polyvalent metal ions, preferably selected from the group consisting of complexone I (nitrilo-triacetic acid), Complexone II (ethylenediamine-tetraacetic acid) and complexone III (disodium ethylenediamine tetraacetic acid). Dental material according to one of the preceding claims, characterized in that the nanodiamonds before cleaning and / or after cleaning an at least one thermal Treatment, preferably annealed, continue preferably at 400-450 ° C more than 0.5 hours to be heated. Dental material according to claim 6, characterized that the nanodiamonds after cleaning and subsequent thermal Treatment repeated with at least one acid and / or at least one chelating agent to be cleaned. Dental material comprising a redox initiator system an initiator and a coinitiator according to any one of claims 2 to 7, characterized in that the initiator and the coinitiator in spatially separated components of the dental material, is preferably present in a two-component system. Dental material according to claim 8, characterized in that that the component containing the initiator and / or the coinitiator containing component has nanodiamonds. Dental material according to claim 8 or 9, characterized that the component (s) more than 3 hours, preferably more than 1 day, more preferably more than 1 week, more preferably more than 3 months, more preferably more than 6 months, further preferably more than 12 months, more preferably more than 24 months is stable on storage (are). Use of the dental material according to one of the preceding Claims as filling material, underfilling material, Buttstock material, fastening material, bonding material, provisional and permanent crown and bridge material, bonding material, Dental material for the production of inlays, onlays, veneers, artificial teeth, model materials, fissure sealing material and root canal sealing material. Hardened dental material, available of a polymerizable dental material according to any one of claims 1 to 10. Process for producing a nanodiamond-containing Dental material, wherein the dental material is preferably a redox initiator system, more preferably a redox initiator system having at least one Initiator and / or at least one coinitiator comprising the steps: - at least one-time cleaning of the Nanodiamonds with at least one acid and / or at least an organic solvent and / or at least one chelating agents, - optionally washing and / or neutralization the nanodiamond, preferably with distilled water on preferably with chloride-free water, - possibly Drying the nanodiamonds and - incorporation of Nanodiamonds in the dental material. Method according to claim 13, characterized in that that the method further comprises the step of: - at least one-time thermal treatment of the nanodiamond, wherein the nanodiamonds preferably annealed, more preferably at 400-450 ° C more than 0.5 hours, more preferably 1 h at 425 ° C are heated. Method according to claim 13 or 14, characterized that the incorporation of the nanodiamonds into the initiator of the Redox initiator system comprehensive component of the dental material he follows.