Roehm Gmbh & Co Kg

Roehm Gmbh Chemische Fabrik

Other

Huels Aktiengesellschaft

Rohm Gmbh

Rohm Gmbh Chemische Fabrik

Michael Meier-Kaiser

Hans Lorenz

Volker Benz

Michael Mueller

Uwe Numrich

Klaus Hofmann

Thomas Pfaff

Martin Berkenkopf

Udo Fischer

Michael M&uuml;ller

Roger Hugh Emerson

Werner Siol

Heinz Gross

Stefan Rober

Wolfgang Scharnke

Herbert Groothues

Christoph Krohmer

Volker Mende

Claude Guenanten

Helmut Haering

Detlef Birth

Horst Greb

Helmut Haring

Georg Oenbrink

Bernhard Schaefer

Andreas Fetzer

Berthold Schoenig

Klaus-Ernst P&ouml;hlmann

Klaus-Ernst Poehlmann

Walter Meon

Christopher Neuroth

Klaus Koralweski

Christoph Steinfels

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 invention relates to a method for regulating the minimal value of the pressure in the first half of the metering zone in a direction of conveyance in a single-screw degassing extruder or in a cascade extruder during the conveying of a melt consisting of a thermoplastic. The single-screw degassing extruder or the cascade extruder each have a first screw section (), a degassing zone (), a metering zone (), and a measuring control loop (M), which includes a pressure measuring sensor (P) in the first half of the metering zone, a regulator (R) and an actuator (S) for influencing the pressure in the metering zone. The pressure is measured by the pressure measuring sensor (P) and is set by the regulator (R) and the actuator (S) so that the minimal value at the location of measurement ranges from 0.1 to 10 bar.

Method and device for regulating pressure in a single-screw degassing extruder or in a cascade extruder

Injection-molding materials comprised of polycarbonate can be processed into optically isotropic films in a chill roll extrusion method. The optically isotropic films for protecting data carriers (CD-ROMS) from becoming scratched, or they are used as supporting materials for the information layer.

Optically isotrophic polycarbonate films and a method for the production thereof

The invention relates to a polycarbonate composite material which can be thermoplastically shaped and which comprises at least two layers. The invention is characterised in that at least one layer comprises an LOI value of lower than 29 and at least one layer comprises an LOI value of higher than 29. The invention also relates to methods for producing said material, the use of the same and flame-proof polycarbonate moulded parts.

Polycarbonate composite material which can be thermoplastically shaped, methods for the production thereof, use of the same and a flame-proof polycarbonate moulded part

Multilayer plastic composites containing at least two incompatible plastics, A and B, in which the layering sequence alternates between A and B, the layers of plastic B are discontinued at regular intervals, and the resulting gaps in the layers are filled in with plastic A, exhibit good adhesion between the layers. In preferred embodiments of the invention, the amorphous, crystalline, or semi-crystalline plastic B has a higher coefficient of thermal expansion than the amorphous plastic A. The plastic composite is preferably produced via coextrusion.

Plastic composites made from incompatible plastics

A light-permeable, IR-reflecting body which contains a stiff, amorphous base material comprised of light-permeable plastic and IR-reflecting particles which are oriented parallel to the surface, said light-permeable IR-reflecting body having a transmissivity (T) in the visible range of 45-75%, an overall energy permeability (g) of 30-60%, and a T/g ratio of >1.15, and the IR-reflecting particles oriented parallel to the surface are disposed in a coating layer comprised of a transparent water-insoluble binder, which layer is 5-40 micron thick and adheres to the base material, wherewith red-reflecting particles with a layer of titanium dioxide 60-120 nm thick on a platelet-shaped carrier pigment are present in the aforesaid coating layer in the amount of 20-40 wt. % of said coating layer.

Infrared-reflecting bodies

An apparatus for calibrating hollow chamber sheet extruded lines out of thermoplastic resin includes a vacuum housing and a planar intake area at a first end of the vacuum housing. The planar intake area is configured to receive the extruded line. Support rollers within the vacuum housing are configured to support the extruded line. The extruded line exits the vacuum housing through a planar outlet area located at a second end of the vacuum housing opposite the first end.

Apparatus for the calibration of hollow chamber sheet extruded lines

Injection-molding materials comprised of polycarbonate can be processed into optically isotropic films in a chill roll extrusion method. The optically isotropic films are used as covering films for protecting data carriers (CD-ROMS) from becoming scratched, or they are used as supporting materials for the information layer.

Optically isotropic polycarbonate films and a method for the production thereof

The invention relates to optical diffuser plates (1) made of transparent plastics such as polycarbonate or polymethacrylate. Several thin strips (2) made of plastic B inserted into plates made of transparent plastic A with the proviso that A and B are incompatible and the strips (2) made of plastic B are subsequently withdrawn. The hollows that are formed in the plate (1) made of plastic A are used to deflect light.

Optical diffuser plates

Process for preparing multilayer plastic composites of incompatible plastics

An extrusion system includes a main extruder and a secondary injection extruder. Both extruders are connected via a three-way valve. The main extruder has a mixing section downstream of the junction point with the secondary injection extruder. An accelerated switch between molding masses with different colors can be made by switching the three way valve.

Extrusion system and process for minimizing color change times in

A process for the extrusion of plastic plates with very finely structured surface using an extrusion system which is equipped with an extruder and a three roll polishing stack containing a roller with the structuring surface. The system is designed for coextrusion and the plastic plates are produced via two extruders as a coextrudate CX from a highly viscous basic molding compound BF and a low viscosity molding compound NF which is extruded on BF. The surface of said plates is structured via the three roll polishing stack. Fresnel lenses produced by the process may be used in solar collectors.

Process for manufacture of fresnel lenses

Process for manufacture of Fresnel lenses

The height of the bulge in the glazing roll gap of a supercalender in the extrusion of plates or films of a thermoplastic material smoothed on both sides may be controlled by measuring the location of the edges of the plastic sheet by means of measuring sensors and regulating the speed of the roll or the rate of extrusion of the polymer melt based on the width of the sheet so that the height of the bulge is always kept within tight tolerances.

Method and apparatus for preparing thermoplastic sheets, films, and

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Alsbach-Haehnlein, Germany

Michael Meier-Kaiser