Abstract: The invention relates to a silicon dioxide dispersion that comprises a) an outer flowable phase containing 1) polymerizable monomers, oligomers and/or prepolymers that can be converted to polymers by non-radical reaction; and/or 2) polymers, and b) a disperse phase containing amorphous silicon dioxide. The inventive dispersion is characterized in that the average particle size dmax of the silicon dioxide as measured by small angle neutron scattering (SANS) is between 3 and 50 nm at a maximum half-width of the distribution curve of 1.5 dmax. Such a silicon dioxide dispersion can be easily manufactured even at higher concentrations of the disperse phase and can be used to produce polymer materials that have advantageous properties, especially advantageous mechanical properties.

Abstract: The invention relates to a silicon dioxide dispersion that comprises a) an outer flowable phase containing 1) polymerizable monomers, oligomers and/or prepolymers that can be converted to polymers by non-radical reaction; and/or 2) polymers, and b) a disperse phase containing amorphous silicon dioxide. The inventive dispersion is characterized in that the average particle size dmax of the silicon dioxide as measured by small angle neutron scattering (SANS) is between 3 and 50 nm at a maximum half-width of the distribution curve of 1.5 dmax. Such a silicon dioxide dispersion can be easily manufactured even at higher concentrations of the disperse phase and can be used to produce polymer materials that have advantageous properties, especially advantageous mechanical properties.

Abstract: The object of the invention is a method for the production of a nano-scale silicon dioxide, said method comprising the following steps: a) provision of an aqueous suspension of a colloidal silicon dioxide with an average particle size of 1 to 500 nm; b) allowing said suspension to react with an organosilane or organosiloxane in an aprotic cyclic ether and silanization of the colloidal silicon dioxide; c) separation of the aqueous phase of the reaction mixture from the organic phase; d) allowing the organic phase to react again with an organosilane or organosiloxane in an aprotic cyclic ether and silanization of the colloidal silicon dioxide; e) separation of the aqueous phase of the reaction mixture from the organic phase.

Abstract: The invention relates to a silicon dioxide dispersion that comprises a) an outer flowable phase containing 1) polymerizable monomers, oligomers and/or prepolymers that can be converted to polymers by non-radical reaction; and/or 2) polymers, and b) a disperse phase containing amorphous silicon dioxide. The inventive dispersion is characterized in that the average particle size dmax of the silicon dioxide as measured by small angle neutron scattering (SANS) is between 3 and 50 nm at a maximum half-width of the distribution curve of 1.5 dmax. Such a silicon dioxide dispersion can be easily manufactured even at higher concentrations of the disperse phase and can be used to produce polymer materials that have advantageous properties, especially advantageous mechanical properties.

Abstract: The invention relates to organically modified, stable in storage, UV curable, NIR permeable silicic acid polycondensates which are photostructurable in layers having a thickness of 1 to 150 ?m. The invention also relates to the production and use thereof as negative resists. The polycondensates according to the invention are obtainable by condensation of organically modified silanediols of the formula I with organically modified silanes of the formula II. Ar2Si(OH)2 ??(I) RSi(OR?)3 ??(II) The radicals are identical or different and have the following meaning: Ar=a radical having 6 to 20 carbon atoms and at least one aromatic group, R=an organic radical having 2 to 15 carbon atoms and at least one epoxy group and/or at least one C?C double bond, R?=methyl or ethyl. Condensation occurs without the addition of water. The molar ratio of said compounds I and II is 1:1.

Abstract: The invention relates to hydrolyzable fluorinate silanes, methods of their roduction and of their use for producing silicic acid polycondensates and hetero silicic acid polycondensats The silanes in accordance with the invention are of the general formula: {[R'-(Y).sub.e ].sub.c+1 (C.sub.6 F.sub.4-c) (C.sub.6 F.sub.4).sub.d }.sub.f SiR.sub.a X.sub.b (I) in which the groups and indices are identical or different and have the following meaning:R=alkyl, alkenyl, aryl, alkylaryl or arylalkyl, substituted if required, each with 1 to 15 carbon atoms, whereby the groups may be interrupted by oxygen or sulfur atoms, ester, carbonyl, amide or amino groups;R'=I, Br, Cl (if d.noteq.0), F (if d.noteq.0), H (if X.noteq.H or R.noteq.methyl or e=1) or an organic group with 1 to 50 carbon atoms;X=hydrogen, halogen except fluorine, hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR".sub.