Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
  • C09D7/40—Additives
  • C09D7/66—Additives characterised by particle size
  • C09D7/67—Particle size smaller than 100 nm
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
  • C09D7/40—Additives
  • C09D7/60—Additives non-macromolecular
  • C09D7/61—Additives non-macromolecular inorganic
  • C09D7/62—Additives non-macromolecular inorganic modified by treatment with other compounds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K3/00—Use of inorganic substances as compounding ingredients
  • C08K3/34—Silicon-containing compounds
  • C08K3/36—Silica
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K9/00—Use of pretreated ingredients
  • C08K9/04—Ingredients treated with organic substances
  • C08K9/06—Ingredients treated with organic substances with silicon-containing compounds
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/26—Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
  • Y10T428/263—Coating layer not in excess of 5 mils thick or equivalent

Definitions

• the invention relates to particle-containing coatings which have on their surface a higher concentration of particles than in their interior, and their use.
• Particles - in particular nanoparticles - containing coating systems are state of the art.
• Corresponding coatings are described for example in EP 1 249 470, WO 03/16370, US 20030194550 or US 20030162015.
• the particles lead to an improvement in the properties of the corresponding coatings, in particular with regard to their scratch resistance and optionally also their chemical resistance.
• a frequently occurring problem when using the - usually inorganic - particles in organic coating systems consists in a usually insufficient compatibility of particles and paint matrix. This can lead to the particles not being able to be dispersed sufficiently well in a coating matrix. In addition, even well-dispersed particles can settle at longer stand or storage times, possibly forming larger aggregates or agglomerates, which can not or only with difficulty be separated into the original particles during a redispersion.
• Lacquers which have smooth surfaces after their application and hardening can generally not be produced in this way or can only be produced by cost-intensive processes.
• coatings containing a nanoparticle-modified binder are also known. These can be prepared by reacting the reactive functionalized particles with a binder having a complementary function. Ie.
• the organofunctional particle is chemically incorporated into the paint matrix not only during paint curing but also during binder production.
• Such systems are described for example in EP 1 187 885 A or WO 01/05897. However, they have the disadvantage of being relatively expensive to produce, which leads to high production costs.
• a coating resin of hydroxy-functional prepolymers in particular of hydroxy-functional polyacrylates and / or polyesters, used in the paint curing with a isocyanate-functional hardener (polyurethane coatings) and / or a melamine hardener (melamine coatings) are reacted.
• the polyurethane coatings are characterized by particularly good properties. In particular, polyurethane coatings have superior chemical resistance, while melamine coatings generally have better scratch resistance.
• these types of paints are used in particularly high-quality and demanding fields of application, for example as clearcoats or topcoats for OEM coatings in the automotive and vehicle industry. Likewise, most automotive refinish topcoats are of such systems.
• the layer thicknesses of these coatings are typically in the range from 20 to 50 ⁇ m.
• Melamine paints are usually 1-component paints, the baking temperatures are typically in a comparable temperature range. Especially with these high-quality paints, a further property improvement would be desirable. This applies in particular to vehicle topcoats. So especially the achievable scratch resistance of conventional car paints is not sufficient, so it is z. B. in the car wash by particles in the wash water to a noticeable scratching of the paint. In the long term, the gloss of the paint is sustainably damaged. Here would be desirable formulations that can achieve better scratch resistance.
• a particularly advantageous way of achieving this object is the use of particles which have on their surface organo-functions which are reactive with the paint resin or with respect to the hardener.
• Such particles with suitable organ functions are already known in principle. Like their use in coatings, they are described, for example, in EP 0 768 351, EP 0 832 947, EP 0 872 500 or DE 10247359.
• the scratch resistance of paints can be significantly increased by the incorporation of such particles.
• no optimal results are obtained with all of the methods described in the prior art when using these particles.
• the corresponding coatings have such high particle contents that a
• paint-containing paint systems are described, which are characterized in that there are more particles in a surface segment of the paint than in a bulk segment.
• the advantage of this particle distribution is the comparatively low particle concentration, which is needed for a significant improvement in the scratch resistance.
• the desired high affinity of the particles to the paint surface is achieved by applying a silicone resin as a surface-active agent to the particle surfaces.
• the modified particles thus obtained have - for silicones often typical - a relatively low surface energy. As a result, they preferably arrange themselves on the surface of the paint matrix.
• a disadvantage of this method is the fact that not only the silicone resin modification of the particles, but also the preparation of the silicone resins required for this purpose is itself technically complicated. The latter is particularly problematic because it is necessary for achieving a good scratch resistance, the silicone resins with organ functions, eg. As carbinol functions to provide over which the correspondingly modified particles can be chemically incorporated in the paint curing in the paint. Such functionalized silicone resins are not available commercially or only to a very limited extent. Above all, however, the choice of possible organ functions in this system is relatively limited. Therefore, in this system, as well as in all other systems according to the prior art, no optimal results are achieved.
• the object of the invention was therefore the development of a paint system that overcomes the disadvantages of the prior art.
• the invention provides coatings (B) prepared from coating formulations (B1) which contain a) 20-90% by weight, based on the solids content, of a coating resin (L) having reactive groups, b) 0-90% by weight , based on the solids content, one
• Paint hardener (H) which has reactive functions with which it can react with the reactive groups of the coating resin (L) in the paint curing, c) 0.05 to 15 wt .-%, based on the solids content, of particles (P ) and d) 0 - 90 wt .-%, based on the total coating formulation (Bl), of a solvent or a solvent mixture, wherein a) the cured coating (B) aa) on its surface or ab) in the near-surface layers measured 1000 nm thick from the surface or ac) have a higher concentration of the particles (P) at their surface as well as in the near-surface layers measured 1000 nm thick than in their interior, and in which b) the particles (P) are obtainable by reacting colloidal metal or silicon oxide sols (P1) with organosilanes (A) selected from the general formula (I) and (II)
• R 1 is hydrogen, alkyl, cycloalkyl or aryl radicals each with 1 to 6 C atoms, wherein the carbon chain may be interrupted by non-adjacent oxygen, sulfur or NR 3 groups,
• R 2 is alkyl, cycloalkyl, aryl or arylalkyl radicals having in each case 1 to 12 C atoms, where the carbon chain may be interrupted by nonadjacent oxygen, sulfur or NR 3 groups,
• R 3 is hydrogen, alkyl, cycloalkyl, aryl, arylalkyl, aminoalkyl or aspartate, R 1 is hydrogen or any organic radical,
• A is a divalent, optionally substituted alkyl, cycloalkyl or aryl radical having 1-10 carbon atoms, which may optionally be interrupted by oxygen, sulfur or NR 3 - groups
• X is an organo function which reacts in the paint curing with a chemical reaction
• Y is an organo function which - optionally after the cleavage of the Si-Y bond - in the paint curing a chemical reaction with functions of the paint resin (L) or the
• Paint hardener (H) can mean, and n the values 0, 1 or 2, m the values 0, 1 or 2 and q can take the values 0 or 1.
• the solids content comprises those coating components which remain in the paint during the curing of the paint.
• the accumulation of the particles on the surface and / or in the near-surface layers is preferably limited to the upper 500 nm or 200 nm and particularly preferably to the uppermost 100 nm of the coatings (B).
• the invention is based on the discovery that the particles (P) during application and curing of the paint are preferably arranged on or near the surface of the coating (B) according to the invention. This discovery is particularly noteworthy because the silane modification of the particles (P) causes the particles on their surfaces reactive organic groups -. As hydroxyl functions, primary or secondary amine functions, isocyanate functions, protected isocyanate functions - have. These relatively polar organ functions commonly do not result in surfaces with particularly low surface energies. A preferred independent arrangement of the particles at or near the paint surface was therefore not to be expected, the near-surface distribution of the particles (P) in the coating (B) is completely surprising for the expert.
• the near-surface distribution of the particles (P) in the cured coating (B) means that when using the particles (P) in paint systems, the scratch resistance of the resulting coating (B) is not proportional to
• the small contents of the usually relatively expensive particles (P) allow for a comparatively cost-effective production of highly scratch-resistant paints, on the other hand reduce the low particle contents - possibly negative - influences the particles on other paint properties, such.
• the coating (B) according to the invention with low contents of synthetically readily accessible particles represents a great advantage over the prior art.
• the enrichment of the particles according to the invention on the surface preferably results from an independent arrangement of the particles. That when applying the coating formulation of the invention (Bl) are no special process steps - such. the application of different paint layers, each with different particle concentrations or aftertreatment of the already applied coating with a particle dispersion - required to achieve the particle distribution according to the invention.
• the coating formulations (B1) which can be processed to give the coatings (B) according to the invention are likewise provided by the present invention.
• the paint resin (L) and the paint hardener (H) preferably have sufficiently many reactive groups that a three-dimensional polymer network can form during the curing of the coating formulation (B1).
• the paint resin (L) preferably contains a hydroxyl-functional (pre) polymer, particularly preferably hydroxyl-functional polyacrylates and / or polyesters.
• the paint curing agent (H) preferably contains protected and / or unprotected isocyanate groups and / or contains melamine-formaldehyde resins.
• the coatings (B) are prepared from coating formulations (B1) which a) 30-80 wt .-%, based on the solids content of the paint resin (L), b) 5-60 wt .-%, based on the solids content of the paint curing agent (H), c) 0.1-12 wt .-%, based on the solids content, to
• Particles (P) and d) 0 to 70 wt .-%, based on the total coating formulation (Bl), a solvent or a solvent mixture.
• the coating formulations contain
• the proportion of solvent or solvents in the total coating formulation (Bl) is particularly preferably from 10 to 50% by weight.
• the coating formulations (B1) for the coatings (B) according to the invention are typically processed by the following working steps: coating of a substrate, drying and curing, in which case the last two steps can also take place simultaneously, in particular in 2-component paints.
• the content of particles (P) in the coating (B) is preferably at 0.1 to 12 wt .-%, based on the solids content, particularly preferably at 0.2 to 8 wt .-%. In very particularly advantageous embodiments of the invention, the content of particles (P) at 0.5 to 5 wt .-%, based on the solids content, in particular 0.7 to 3 wt .-%.
• the coatings (B) according to the invention are preferably used as clearcoats and / or topcoats, in particular for automotive OEM or automotive refinishes.
• the groups R ⁇ are preferably
• Methyl or ethyl radicals preferably represent alkyl radicals having 1 to 6 carbon atoms or phenyl radicals, in particular methyl, ethyl or isopropyl radicals. R 1 preferably has at most 10 carbon atoms, in particular at most 4 carbon atoms.
• R 4 preferably represents hydrogen or an alkyl radical having 1-10, particularly preferably 1-6, carbon atoms, in particular methyl or ethyl radicals.
• A is preferably a divalent alkyl radical having 1-6 carbon atoms which may optionally be interrupted by oxygen, sulfur or NR.sup.1 groups.
• the organosilanes (A) used are compounds of the general formula (I) in which the function X is an isocyanate or-particularly preferably-a protected isocyanate function.
• the latter releases an isocyanate function upon thermal treatment.
• Preferred elimination temperatures of the protecting groups are present at 80 to 200 0 C, particularly preferably at 100 to 170 0 C.
• the protecting groups may secondary or tertiary alcohols such as isopropanol or t-butanol, CH- acidic compounds, such as. For example, diethyl malonate, acetylacetone, ethyl acetoacetate, oximes, such as. B.
• Phenols such as phenol, o-methylphenol, N-alkylamides, such as. N-methylacetamide, imides such as phthalimide, secondary amines such as e.g. Diisopropylamine, imidazole, 2-isopropylimidazole, pyrazole, 3,5-dimethylpryazole, 1, 2, 4-triazole and 2.5 dimethyl-1, 2, 4-triazole can be used.
• protecting groups such as butane oxime, 3, 5-Diroethylpyrazol, caprolactam, diethyl malonate, methyl malonate, acetoacetic ester, diisopropylamine, pyrrolidone, 1, 2, 4-triazole, imidazole and 2-Isopropylimidazol used.
• protecting groups which allow a low stoving temperature, such.
• Isocyanate groups are preferably used in coating formulations (B1) which contain as curing agent (H) a compound which also has protected isocyanate functions.
• the corresponding coating formulations (B1) are thus IK polyurethane coatings.
• the protected isocyanate groups of the particles (P) are provided-at least predominantly-with protective groups which have a lower cleavage temperature than all or at least the majority of the protective groups of the protected isocyanate groups of the paint curing agent (H) .
• X preferably represents a hydroxyl or thiol function, a group of the formula NHR 1, a heterocyclic ring containing an NH function or an epoxide ring.
• X represents a piperazine ring.
• R 5 has the meanings of R 1 on. If X represents an epoxide ring, this is before, during or after the reaction of the silane (A) with the particles (Pl) by a suitable method, for. B. opened by a reaction with ammonia, an amine, water or an alcohol or an alcoholate.
• silanes (A) of the general formula (II) are used in the preparation of the particles (P), the ring structure of this silane is broken during particle production by the attack of a hydroxyl group of the particles (P1) on the silicon atom of the silane (A) the Si-Y bond opened.
• Y is preferably a function which, after this cleavage of the Si-Y bond, is a hydroxyl or
• Thiol function or a group of the formula NHR ⁇ represents.
• organosilanes (A) which correspond to the general formulas (III) or (IIIa)
• B is oxygen, sulfur, carbonyl, ester, amide or NR ⁇ represents,
• R 6 has the meanings of R 1
• x can assume the values from 0 to 10 and the remaining variables have the meanings given in the general formulas (I) and (II).
• the particulate sols (P1) are functionalized with organosilanes (A) which correspond to the general formulas (IV) or (IVa)
• organosilanes (A) as compounds of the general formulas (V) or (VI)
• any mixtures of the silanes (A) with other silanes (S1), silazanes (S2) or siloxanes (S3) can be used for surface modification of the particulate sols (P1) in addition to the silanes (A).
• the silanes (S1) have either hydroxysilyl groups or else hydrolyzable silyl functions, the latter being preferred.
• these silanes can have further organ functions, but it is also possible to use silanes (SI) without further organ functions.
• silazanes (S2) or siloxanes (S3) hexamethyldisilazane or hexamethyldisiloxane are particularly preferably used.
• the proportion by weight of silanes (A) in the total amount formed from silanes (A) and (S1), silazanes (S2) and siloxanes (S3) is at least 50% by weight, more preferably at least 70% by weight and 90% by weight, respectively.
• the use of the compounds (S1), (S2) and (S3) is completely dispensed with.
• the preparation of the particles (P) is based on colloidal silicon or metal oxide sols (P1) which are generally used as a dispersion of the corresponding submicron-sized oxide particles in an aqueous or non-aqueous
• sols are 1-50% solutions, preferably a 20-40% solution.
• Typical solvents are in addition to water, especially alcohols, especially alcohols having 1 to 6 carbon atoms, often other isopropanol but also other low molecular weight alcohols, such as.
• the preparation of the particles (P) from the colloidal silicon or metal oxides (P1) and the organosilanes (A) preferably takes place directly during the mixing of the reactants, if appropriate in the presence of further solvents and water.
• the order of addition of the individual reactants is arbitrary. However, preference is given to adding the silanes (A) - optionally in a solvent and / or in mixtures with other silanes (S1), silazanes (S2) or siloxanes (S3) - to the aqueous or organic particulate sol (P1).
• This sol may be acidic, e.g. By hydrochloric acid or trifluoroacetic acid, or basic, e.g. B. by ammonia stabilized.
• the reaction is generally carried out at temperatures of 0-200 ° C., preferably at 20-80 ° C., and more preferably at 20-60 ° C.
• the reaction times are typically from 5 minutes to 48 hours, preferably from 1 to 24 hours.
• acidic, basic or heavy metal-containing catalysts preference is given to omitting the addition of separate catalysts.
• the colloidal silicon or metal oxide sols (P1) are often present in aqueous or alcoholic dispersion, it may be advantageous for the solvent (s) during or after the preparation of the particles (P) against another solvent or against another solvent mixture exchange. This can be done for example by distillative removal of the original solvent, wherein the new solvent or solvent mixture can be added in one or more steps before, during or even after distillation.
• Suitable solvents may be, for example, water, aromatic or aliphatic alcohols, where aliphatic alcohols, in particular aliphatic alcohols having 1 to 6 carbon atoms (eg., Methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, the various regioisomers of pentanol and hexanol), esters (eg ethyl acetate, propyl acetate, butyl acetate, butyl diglycol acetate, methoxypropyl acetate), ketones (eg acetone, methyl ethyl ketone), ethers (eg diethyl ether, t-butyl methyl ether, THF), aromatic solvents (toluene, the various regioisomers of xylene, but also mixtures such as solvent naphtha), lactones (eg,
• aprotic solvents or solvent mixtures which consist exclusively or at least partly of aprotic solvents are preferred.
• Aprotic solvents are advantageous, at least when used in isocyanate-curing coating formulations (B1), ie in IK or 2K polyurethane coatings, since protic solvents, like water, are reactive towards isocyanate functions, leading to undesirable side reactions between hardener (H) and the solvent can lead.
• isocyanate-curing coating formulations (B1) ie in IK or 2K polyurethane coatings
• protic solvents like water
• isocyanate functions leading to undesirable side reactions between hardener (H) and the solvent can lead.
• P hardener
• organosilanes (A) are used in the preparation of the particles (P). of the general formulas (I) or (VI) in which the spacer A is a CH 2 bridge, or cyclic organosilanes of the general formulas (III), (IIIa), (IVa) or (V).
• These silanes are characterized by a particularly high reactivity towards the hydroxyl groups of the particles (P1), so that the functionalization of the particles can be carried out particularly rapidly and at low temperatures, in particular already at room temperature.
• the presence or addition of water in the preparation of the particles (P) is often advantageous because the alkoxysilanes then not only with the Si-OH functions of the particles (Pl), but - after their Hydrolysis - can also react with each other. This results in particles (P), which have a shell of interconnected silanes (A).
• the coating resins (L) contained in the coating formulations (B1) preferably comprise hydroxyl-containing prepolymers, more preferably hydroxyl-containing polyacrylates or polyesters.
• hydroxyl-containing polyacrylates and polyesters are well known in the art and in the relevant literature many times. They are manufactured by many manufacturers and distributed commercially.
• the coating formulations (B1) can be 1-component (1K) or 2-component (2K) coatings.
• melamine hardeners tris (aminocarbony) triazines and / or hardeners which possess protected isocyanate groups are preferably used as paint hardeners (H).
• compounds having free isocyanate groups are preferably used as hardener (H).
• Both melamine hardener and hardener with protected or unprotected NCO groups are well known in the prior art and described in many cases in the corresponding literature. They too are commercially available and are distributed by numerous manufacturers.
• the paint curing agent (H) contains free or protected isocyanate groups. Most commonly used for this purpose di- and / or polyisocyanates, which may have been previously provided with the respective protective groups. As isocyanates, it is possible in principle to use all customary isocyanates, as are frequently described in the literature.
• Common diisocyanates are, for example, diisocyanatodiphenylmethane (MDI), both in the form of crude or industrial MDI and in the form of pure 4,4'- or 2,4'-isomers or mixtures thereof, tolylene diisocyanate (TDI) in the form of its various regioisomers, diisocyanatonaphthalene (NDI), isophorone diisocyanate (IPDI), perhydrogenated MDI (H-MDI), tetramethylene diisocyanate, 2-methylpentamethylene diisocyanate, 2, 2, 4-trimethylhexamethylene diisocyanate,
• MDI diisocyanatodiphenylmethane
• TDI tolylene diisocyanate
• NDI diisocyanatonaphthalene
• IPDI isophorone diisocyanate
• H-MDI perhydrogenated MDI
• tetramethylene diisocyanate 2-methylpentam
• polyisocyanates are polymeric MDI (P-MDI), triphenylmethane triisocyanate and also all isocyanurate or biuret trimers of the diisocyanates listed above.
• P-MDI polymeric MDI
• triphenylmethane triisocyanate triphenylmethane triisocyanate and also all isocyanurate or biuret trimers of the diisocyanates listed above.
• the ratio of optionally blocked isocyanate groups of all constituents of the coating formulation (B1) to the isocyanate-reactive groups of all constituents of the coating formulation (B1) is usually from 0.5 to 2, preferably from 0.8 to 1.5 and more preferably from 1, 0 to 1.2 selected.
• organo-functions of the silanes to be used for particle modification i.e.
• the coating formulations (B1) may also contain the customary solvents and the additives and coating components customary in coating formulations as component (E).
• component (E) may also contain the customary solvents and the additives and coating components customary in coating formulations as component (E).
• flow aids such as UV absorbers and / or radical scavengers, thixotropic agents and other solids.
• the coating formulations (Bl) may also contain pigments.
• the coating formulations (B1) according to the invention are prepared by the
• Particles (P) are added during the mixing process as a powder or as a dispersion in a suitable solvent.
• a further method is preferred in which first of all a masterbatch is produced from the particles (P) and one or more coating components, with particle concentrations> 15% by weight, preferably> 25% by weight and particularly preferably> 30% by weight .-%.
• this masterbatch is then mixed with the other coating components. Used in the production of the masterbatch by a
• Particle dispersion it may be advantageous if the solvent of the particle dispersion in the course of masterbatch production is removed, for. B. via a distillation step, or exchanged for another solvent or solvent mixture.
• inventive coatings (B) can be used to coat any desired substrates for improving scratch resistance, abrasion resistance or chemical resistance.
• Preferred substrates are plastics, such as
• the coatings (B) particularly preferably serve as scratch-resistant clearcoats or topcoats, in particular in the vehicle industry.
• the coating formulations (B1) can be applied by any methods, such as dipping, spraying, and casting methods. Also an application of the coating formulation (Bl) to a basecoat for a "wet on wet" method is possible Curing is generally carried out by heating under the particular conditions required (2K coatings typically at 0 -.
• suitable catalysts 160 0 C are, in particular, acidic, basic as well as heavy-metal-containing compounds...
• Synthesis Example 1 Preparation of an alkoxysilane with diisopropylamine-protected isocyanate groups (silane 1). There are (from Borchers GmbH catalyst VP 0244) provided 86.0 g of diisopropylamine and 0.12 g Borchi® catalyst and heated to 80 0 C. Within 1 h 150.00 g of isocyanatomethyl-trimethoxysilane are added dropwise and the mixture for Stirred at 60 0 C for 1 h. 1 H-NMR and IR spectroscopy show that the isocyanatosilane has been completely reacted.
• Synthesis Example 2 Preparation of an alkoxysilane with diisopropylamine-protected isocyanate groups (silane 2).
• Synthesis Example 3 Preparation of SiO 2 Nanosol Particles Modified with Blocked Isocyanate Groups 1.40 g of the diisopropylamine-protected isocyanatosilane prepared according to Synthesis Example 1 (silane 1) are dissolved in 1.0 g of isopropanol. Then, within 30 minutes, 20 g of a SiO 2 organosol (IPA-ST from Nissan Chemicals,
• the resulting dispersion is stirred for 3 h at 60 0 C and then for 18 h at room temperature. Thereafter, 18.1 g of methoxypropyl acetate are added. The mixture is stirred for a few minutes and then distilled off a large part of the isopropanol at 70 0 C. Ie. It is distilled until the nanoparticle sol has been concentrated to 29.4 g.
• the result is a dispersion having a solids content of 25.5 wt .-%.
• the SiO 2 content is 20.8% by weight and the content of protected isocyanate groups in the dispersion is 0.17 mmol / g.
• the dispersion is slightly cloudy and shows a Tyndall effect.
• Examples 1 to 7 Preparation of a 1-component coating formulation containing SiO 2 nanosol particles which have been modified with blocked isocyanate groups To prepare a coating formulation according to the invention, an acrylate-based
• Paint polyol having a solids content of 52.4% by weight (solvent: solvent naphtha, methoxypropyl acetate (10: 1)), a hydroxyl group content of 1.46 mmol / g resin solution and an acid number of 10-15 mg KOH / g with Desmodur® BL 3175 SN from Bayer (butanoxime-blocked polyisocyanate, blocked NCO content of 2.64 mmol / g).
• the amounts of the respective components used can be found in Table 1. Subsequently, the in Table 1. specified amounts of the dispersion prepared according to Synthesis Example 3 was added. In each case, molar ratios of protected isocyanate functions to hydroxyl groups of 1.1: 1 are achieved.
• Example 8 Preparation of a 1K coating formulation containing SiO 2 nanosol particles modified with blocked isocyanate groups
• Synthesis Example 4 on the total solids content is 2.2 wt .-%. Furthermore, 0.01 g of a dibutyltin dilaurate and 0.03 g of a 10% strength by weight solution ADDID® 100 from TEGO AG (polysiloxane-based leveling agent) are mixed in isopropanol, giving a coating formulation of about 50% by weight. % Solids content is obtained. This initially slightly turbid mixture is stirred for 48 h at room temperature to give a clear coating formulation.
• ADDID® 100 polysiloxane-based leveling agent
• the coating compositions from Examples 1 to 8 are in each case wound up on a glass plate by means of a film applicator Coatmaster® 509 MC from Erichsen using a squeegee with a gap height of 120 ⁇ m. Subsequently, the obtained
• Both the coating formulations of the examples and of the comparative examples give optically flawless, smooth coatings.
• the particles are preferably located on the surface of the respective coating.
• FIG. 1 shows a TEM image of a vertical section produced by a paint from a paint formulation according to Example 4. The accumulation of the particles on the paint surface is clearly visible.
• the gloss of the coatings is determined with a gloss meter Micro gloss 20 ° from Byk and is in all paint formulation between 159 and 164 gloss units.
• the scratch resistance of the cured coating films produced in this way is determined using a scouring tester according to Peter-Dahn. For this, a scouring fleece Scotch Brite® 2297 with an area of 45 x 45 mm and a weight of 500 g is weighted. With this, the paint samples are scratched with a total of 40 strokes. Both before and after completion of the scratching tests, the gloss of the respective coating is measured with a gloss meter Micro gloss 20 ° from Byk. As a measure of the scratch resistance of the respective coating, the loss in gloss was determined in comparison with the starting value:

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• 2005
  • 2005-07-22 DE DE102005034347A patent/DE102005034347A1/de not_active Withdrawn
• 2006
  • 2006-06-29 WO PCT/EP2006/006324 patent/WO2007009569A2/de active Application Filing
  • 2006-06-29 KR KR1020087004371A patent/KR20080029004A/ko not_active Application Discontinuation
  • 2006-06-29 CN CNA2006800268875A patent/CN101228239A/zh active Pending
  • 2006-06-29 EP EP06762278A patent/EP1910479A2/de not_active Withdrawn
  • 2006-06-29 US US11/996,417 patent/US20080226901A1/en not_active Abandoned
  • 2006-06-29 JP JP2008521825A patent/JP2009503129A/ja active Pending

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