Stabilisierte Suspensionen von anorganischen Nano-Partikeln

(A1) Die vorliegende Erfindung betrifft eine Suspension von anorganischen Nano-Partikeln, umfassend oder bestehend aus: (a) einer aeusseren Phase, umfassend oder bestehend aus: (a1) polymerisierbaren Monomeren, Oligomeren und/oder Prepolymeren und (a2) einer oder mehreren co-polymerisierbaren oder nicht co-polymerisierbaren organischen Saeuren, und (b) einer dispergierten Phase, bestehend aus: oberflaechenmodifizierten und/oder nicht oberflaechenmodifizierten anorganischen Nano-Partikeln, wobei die anorganischen Nano-Partikel eine mittlere Teilchengroesse von maximal 200 nm besitzen, wobei die Suspension frei ist von SiO2-Partikeln, die mittels eines Sol-Gel-Verfahrens herstellbar sind, wobei die Art und die Menge der co-polymerisierbaren oder nicht co-polymerisierbaren organischen Saeure bzw. Saeuren so ausgewaehlt sind, dass die oberflaechenmodifizierten und/oder nicht oberflaechenmodifizierten anorganischen Nano-Partikel nach Vermischen von einem Gewichtsteil Hexamethylendiisocyanat-Biuret (HDI-Biuret) mit einem Gewichtsteil der Suspension gegen Zusammenballung zu Partikeln einer mittleren Teilchengroesse von zumindest 1000 nm stabilisiert sind.

EP 1947141 A1 UPAB: 20081110 NOVELTY - Inorganic particles suspension comprises an outer phase comprising polymerizable monomers, oligomers and/or pre-polymers and one or more co-polymerizable or non co-polymerizable organic acids; and a dispersed phase comprising surface modified and/or non-surface modified inorganic particles, where the inorganic particles have an average particle size of 200 nm, preferably 100 nm. DETAILED DESCRIPTION - Inorganic particles suspension comprises an outer phase comprising polymerizable monomers, oligomers and/or pre-polymers and one or more co-polymerizable or non co-polymerizable organic acids; and a dispersed phase comprising surface modified and/or non-surface modified inorganic particles, where the inorganic particles have an average particle size of 200 nm, preferably 100 nm, and the type and the amount of the co-polymerizable or non-co-polymerizable organic acid and/or acid is selected so that the surface modified or non-surface modified inorganic particle is stabilized after mixing of 1 part/wt of hexamethylene-diisocyanate-biuret with 1 part/wt of the suspension against accumulation of particles with an average particle size of at least 1000 nm. INDEPENDENT CLAIMS are included for: (1) a preparation of the suspension comprising providing pre-suspension comprising the outer phase and the dispersed phase comprising surface modified and/or non-surface modified inorganic particles, and mixing the provided pre-suspension with the co-polymerizable or not co-polymerizable organic acids or acid anhydrides; and (2) a partly or completely cured dispersion, producible by polymerization of the polymerizable monomers, oligomers and/or pre-polymers, and/or the radically polymerizable monomers, oligomers and/or pre-polymers of the suspension. USE - The co-polymerizable or non co-polymerizable organic acid is useful as a stabilizer to stabilize the surface modified and/or non-surface modified silicon dioxide particles against the accumulation in the suspension, or the surface modified and/or non-surface modified inorganic nano-particle against the accumulation in the suspension. The suspension is useful in lacquer system, preferably clear lacquer systems and pigmented lacquer systems (all claimed). The suspension is useful in automobile lacquering. ADVANTAGE - The suspension is stable against the accumulation of the particles. The inorganic acid in the suspension has increased tensile strength and impact strength, improved scratch and abrasion resistance, and reduced thermal hardening expansion. The suspension is devoid of turbidity.