Roehm Gmbh & Co Kg

Evonik Roehm Gmbh

Rohm Gmbh

Roehm Gmbh

Evonik Rohm Gmbh

Herbert Groothues

Jann Schmidt

Markus Parusel

Helmut Haering

Christoph Krohmer

Guenther Dickhaut-Bayer

Claude Guenanten

Uwe Numrich

Michael Meier-Kaiser

Guenther Ittmann

Hans Lorenz

Ghirmay Seyoum

Hans Lichtenstein

Wolfgang Scharnke

Michael Enders

Detlef Birth

Wangelis Karampougioukis

Girolamo Musci

Claude Guénanten

Berthold Schoenig

Christoph Steinfels

Stephan Neumayer

Christopher Neuroth

Helmut Häring

Walter Meon

Kim Struwe

Berthold SCHÖNIG

Claude Guenaten

An acrylic multilayer foil includes a layer A in which silica particles are uniformly distributed in an acrylic polymer matrix and a coating layer D. Due to adhesive promoting properties of the layer A containing silica particles, the coating layer D can be advantageously applied onto the layer A. The foil has a high weathering resistance and excellent mechanical properties. Therefore, the foil is highly suitable for surface-protection of materials such as polyvinyl chloride (PVC) and for use in high-pressure laminates (HPLs).

Acrylic multilayer foil with improved mechanical properties and a high weathering resistance

A process for producing a light guide plate includes producing a colorless transparent sheet from a colorless transparent material by extrusion with a polishing stack. A printed reflector film is laminated in-line to the colorless transparent sheet. The printed reflector film includes: a thermoplastic reflector film which is opaque white or translucent white and made of a thermoplastic material; and a colorless thermoplastic printed on the thermoplastic reflector film. There is no direct optical contact between the colorless transparent sheet and the thermoplastic reflector film. A glass transition temperature of the printed colorless thermoplastic is above 25&#xb0; C. and below glass transition temperatures of the colorless transparent material of the colorless transparent sheet and of the thermoplastic material of the thermoplastic reflector film.

Light guide plate and method for the production thereof

The invention relates to a method for producing a thermoplastic plastic film. According to said method, the thermoplastic plastic is melted and transported in an extrusion installation comprising an extruder, an extrusion nozzle with a wide-slot delivery opening and a chill roll, which is fixed to a roll system and then leaves the delivery opening of the extrusion nozzle in the form of a flat melted web. Said melted web is then applied to the chill roll and is cooled. The invention is characterised in that it uses an extrusion installation, in which the distance between the delivery opening of the extrusion nozzle and the surface of the cooled roll does not vary by more than +/&#x2212;50 &#x3bc;m during the operating time. The invention also relates to a film of this type and to uses of the latter.

Method for producing a thermoplastic plastic film, film and use thereof

The present invention relates to diffuser sheets for LCD applications encompassing at least one light-scattering polymethyl methacrylate layer which comprises a polymethyl methacrylate matrix and also from 0.5 to 59.5% by weight, based on the weight of the light-scattering polymethyl methacrylate layer, of spherical scattering particles (A) whose median size Vis in the range from 0.1 to 40 &#x3bc;m, and whose refractive index differs from that of the polymethyl methacrylate matrix by a value in the range from 0.02 to 0.2, and from 0.5 to 59.5% by weight, based on the weight of the light-scattering polymethyl methacrylate layer, of spherical particles (B) whose median size Vis in the range from 10 to 150 &#x3bc;m and whose refractive index differs from that of the polymethyl methacrylate matrix by a value in the range from 0 to 0.2, where the total concentration of the spherical scattering particles (A) and particles (B) is in the range from 1 to 60% by weight, based on the weight of the light-scattering polymethyl methacrylate layer, and the spherical scattering particles (A) and spherical particles (B) have a different median particle size V, where the transmittance of the diffuser sheets is in the range from 20 to 70% and their scattering power is greater than 0.3, where the ratio of the square of average surface roughness of the polymethyl methacrylate layer Rto the third power of the size of the spherical particles (B) R/Dis in the range from 0.0002 to 0.1300 &#x3bc;m.

Diffuser disk for LCD applications, method for the production and use thereof

The present invention relates to rear-projection screens which have at least one scattering layer encompassing scattering particles and has at least one backing layer, characterized in that the halved-intensity angle of the scattering layer is greater than or equal to 15&#xb0; and the halved-intensity angle of the backing layer is smaller than or equal to 6.5&#xb0;, where the gloss Rof the backing layer is smaller than or equal to 70.

Stable rear projection screen and method for the production thereof

The present invention relates to a rear-projection screen encompassing at least one light-scattering polymethyl methacrylate layer, which comprises a polymethyl methacrylate matrix and spherical scattering particles (A) and spherical particles (B) with a different median particle size V, where the spherical scattering particles (A) have a median size Vin the range from 0.1 to 40 &#x3bc;m, the difference between the refractive index of the spherical scattering particles (A) and that of the polymethyl methacrylate matrix being in the range from 0.02 to 0.2, where the spherical particles (B) have a median size Vin the range from 10 to 150 &#x3bc;m, the difference between the refractive index of the spherical particles (B) and that of the polymethyl methacrylate matrix being in the range from 0 to 0.2, and where the total concentration of the spherical scattering particles (A) and particles (B) is in the range from 1 to 60% by weight, based on the weight of the light-scattering polymethyl methacrylate layer, where the concentration of the spherical scattering particles (A) c, the thickness of the light-scattering polymethyl methacrylate layer dand the size of the spherical scattering particles (A) Dis selected in such a way that the ratio c*d/Dis in the range from 0.001 to 0.015% by weight*mm/&#x3bc;m, the concentration of the spherical particles (B) c, the thickness of the light-scattering polymethyl methacrylate layer dand the size of the spherical particles (B) Dis selected in such a way that the ratio c*d/Dis in the range from 0.000005 to 0.002% by weight*mm/&#x3bc;mand the ratio of the square of average surface roughness of the polymethyl methacrylate layer Rto the third power of the size of the spherical particles (B) R/Dis in the range from 0.0002 to 0.1300 &#x3bc;m.

Scratch-resistant rear projection screen and method for producing the same

A rear-projection screen that has at least one light-scattering polymethyl methacrylate layer in which is embedded spherical plastic particles; the previously described rear-project screen that has an additional plastic sheet that does not have embedded scattering beads; and a method of making a rear-projection screen.

Rear projection screen and method for the production thereof

The present invention relates to a light-guide body, which has at least one light-entry surface and at least one light-exit surface, the ratio of the light-exit surface area to the light-entry surface area being at least 4, comprising at least one light-guiding layer with a thickness of at least 2 mm, characterized in that the light-guiding layer comprises at least 60% by weight, expressed in terms of the weight of the light-guiding layer, of polymethyl methacrylate and from 0.001 to 0.08% by weight, expressed in terms of the weight of the light-guiding layer, of spherical barium sulphate particles with an average diameter in the range of from 0.3 to 20 &#x3bc;m.

Light-guide body and process for its production

Growing community of inventors

Weiterstadt, Germany

Herbert Groothues