Abstract: A process for producing doped nanoparticles, in particular for N-doped nanoparticles, includes a hydrothermal process using an organic nitrogen-containing compound or a mineral acid having at least one nitrogen atom. In particular, the photocatalytically active particles produced are characterized by a particularly high activity even in visible light.

Abstract: A process for producing doped nanoparticles, in particular for N-doped nanoparticles, includes a hydrothermal process using an organic nitrogen-containing compound or a mineral acid having at least one nitrogen atom. In particular, the photocatalytically active particles produced are characterized by a particularly high activity even in visible light.

Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. A surface covered by the diffractive surface elements on the carrier element can occupy at least a partial region of the carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group including the portion of the plurality of diffractive surface elements, and an orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein together they make a single first image point of an associated first symbol to be represented visible to an observer under particular observation conditions.

Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. A surface covered by the diffractive surface elements on the carrier element can occupy at least a partial region of the carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group including the portion of the plurality of diffractive surface elements, and an orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein together they make a single first image point of an associated first symbol to be represented visible to an observer under particular observation conditions.

Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group. An orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein they make a first point of an associated symbol to be represented visible. A plurality of additional surface element groups each can make a respective additional point of the symbol to be represented visible. The symbol can include a sum of all points represented by the first surface element group and the plurality of additional surface element groups. A movement of the symbol can be perceived by the continuous change in an angle of incidence of the light or an observation angle.

Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group. An orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein they make a first point of an associated symbol to be represented visible. A plurality of additional surface element groups each can make a respective additional point of the symbol to be represented visible. The symbol can include a sum of all points represented by the first surface element group and the plurality of additional surface element groups. A movement of the symbol can be perceived by the continuous change in an angle of incidence of the light or an observation angle.

Abstract: A security device for improving the security against falsification of articles has a carrier element. Arranged on the upper side of the carrier element are a large number of diffractive surface elements. The surface elements respectively form a number of surface element groups, surface structures of which are made to match one another in such a way that they show a point of the symbol to be represented over an entire observation sphere. By changing the angle of incidence of the light and/or the angle of observation of an observer, a continuous movement of the symbol in the observation sphere is perceived by the observer.

Abstract: Magnetic composite particles can be used as proppants and allow for deliberate heating by applying an alternating magnetic field.

Abstract: Optical elements, in particular for holographic applications, have a gradient structure formed by a refractive index gradient and include one or more organic polymers and at least one ionic liquid.

Abstract: The invention relates to a method for producing structured optical materials. It also relates to a device for producing structured optical materials, and to use of the method. In order to create a novel, continuous method for the production of structured optical materials, which is more economical than the known production method, it is proposed within the scope of the invention that optical material be applied to a carrier, a carrier or protective film be laminated onto the optical material, the resulting laminate be exposed to light and thereby structured, and subsequently a delamination of at least one of the films be performed.

Abstract: Magnetic composite particles can be used as proppants and allow for deliberate heating by applying an alternating magnetic field.

Abstract: The invention relates to optical elements with gradient structure, in particular for holographic applications, wherein the gradient structure is formed by a refractive index gradient and a method for production of said optical elements with gradient structure.

Abstract: The invention relates to a method for the production of a flexible, gas-tight, and transparent composite film, comprising a transparent carrier layer made of plastic and a glass-like layer. The method comprises the following steps: a) a temperature-resistant substrate is coated with a lacquer comprising glass or glass-forming pre-stages by a wet chemical process, b) the coating is thermally compressed to form the glass-like layer, c) the transparent carrier layer made of plastic is applied onto the glass-like layer and bonded thereto, and d) the composite of the carrier layer and the glass-like layer is separated from the substrate. The composite films obtained in this way are suitable as encapsulation material or packing material, particularly for the use in displays, illumination and photovoltaics, for example for light-emitting diodes, solar cells, displays, or electronic circuits.

Abstract: The invention relates to a method for producing structured optical materials. It also relates to a device for producing structured optical materials, and to use of the method. In order to create a novel, continuous method for the production of structured optical materials, which is more economical than the known production method, it is proposed within the scope of the invention that optical material be applied to a carrier, a carrier or protective film be laminated onto the optical material, the resulting laminate be exposed to light and thereby structured, and subsequently a delamination of at least one of the films be performed.