Bayer Aktiengesellschaft

Maschinenfabrik Hennecke Gmbh

Klaus Schulte

Wilfried Ebeling

Kurt Krippl

Heinrich Ersfeld

Karl D Kreuer

Hans-Michael Sulzbach

Volker Onnenberg

Heinz Muller

Alberto C Gonzalez-Dorner

Hansjurgen Rabe

Robert Peters

Klaus Nadolski

Uwe K&uuml;nzel

Rolf Coblenz

Dieter Evertz

Bernd Lehmann

Reiner Raffel

Rolf Wiedermann

Werner Dietrich

Heinrich Boden

Hanns I Sachs

Wolfgang Friederichs

Wilhelm Lamberts

Erwin Hoffmann

Peter Kasperek

Walter Schneider

Hans-Ulrich Weber

Christian Wolfrum

James Thompson-Colon

Lothar Klier

Hans Wirtz

Karl-Dieter Kreuer

Wolfgang Friedrichs

Dieter Kreuer

Rudolf Rudhart

Heinz Decker

The present invention is directed to a process and corresponding device for incorporating expanded graphite in a gentle manner into a polyurethane reactive mixture and, on the other hand, processes and corresponding means for reducing or preventing sedimentation of the expanded graphite in the liquid.

Method and device for producing polyurethanes containing filling materials

The present invention is directed to an agitator-free mixing head and a method for agitator-free production of a reaction mixture from an isocyanate and a higher-viscous polyol formulation, wherein both constituents are fed to a mixing zone and mixed with each other therein, whereby a polyol formulation with a viscosity of at least 3000 mPa.s is fed at low pressure into the mixing zone and at least two flows of low-viscosity constituents (isocyanate and optionally low-viscous polyol) are injected into the flow of high-viscous polyol formulation at high pressure.

Method and mixing head for producing a reaction mixture from an isocyanate and a higher-viscous polyol formulation

A process is described for the production of a curable multi-component reaction mixture (and, in particular, a polyurethane), containing filler in which the reaction components are premixed and then mixed with the dry filler in a friction mixer having a conically shaped screw rotatable in a conical mixing chamber. The friction mixer is preferably operated under a fractional load at a low rotational speed.

Process for the production of a filled reaction mixture

Leakage problems can be avoided in an apparatus for the preparation of a solid or cellular plastic-forming, flowable reaction mixture of at least two flowable reaction components and at least one additional component, by providing in the feed pipe of one of the reaction components a mechanical pre-mixer having a stirrer shaft. Upstream of the pre-mixer, a hydraulic motor comprising two meshing toothed wheels which is driven by the components themselves, is disposed in a manner such that one of the toothed wheels is disposed on an extension of the stirrer shaft, and wherein the bearings of the toothed wheels and the stirrer shaft are outwardly enclosed.

Apparatus for the preparation of a flowable reaction mixture

In devices for the production of a reaction mixture, which forms a foamed plastic, from at least two reaction components and a foaming agent, it is possible to determine the content of foaming agent in a reaction component mixed therewith in that an intermediate container is provided for this mixture. The intermediate container is provided with a circulating line in which are arranged a circulating pump and a temperature-compensating viscometer. Optionally, the foaming agent content can be automatically adjusted to the theoretical value via a computer and pulse lines by influencing the drive means of the dosing pumps for the respective reaction component and the foaming agent.

Device for the production of a reaction mixture

A mold for manufacturing polyurethane parts using the RIM process, has two mold halves which between them enclose a mold cavity. The mold cavity is sealed off from the outside by a sealing surface. A gap of 15 to 30 mm depth and 0.15 to 0.25 mm width is provided between the mold cavity and the sealing surface.

Mold for manufacturing polyurethane parts for using the rim process

An apparatus for continuously charging a liquid reactant with a gas is provided. The gas is dispersed in the reactant through a hollow stirrer in a gassing tank. The quantity of gas introduced per unit time is kept constant.

Apparatus for the continuous charging of a liquid reactant with gas for

The present invention relates to an improved apparatus for the production of a flowable mixture which reacts to form foam from flowable components stored in storage containers, wherein prior to metered introduction into a mixing zone, at least one of the components is charged with a defined quantity of gas, by (i) introducing said one component and gas separately into a gasification chamber equipped with a hollow stirrer, (ii) sucking gas into said component through the hollow shaft of the hollow stirrer, and (iii) stirring the gas into the component, until the desired value is attained, the improvement wherein (a) the component is circulated from the storage container through the gasification chamber and back into the storage container, (b) the gas sucked through the hollow shaft of the hollow stirrer being maintained at pressure at least equal to the pressure prevailing in the storage container, and (c) the component fraction remaining in the storage container is homogenized during those periods in which gasification does not take place.

Apparatus for the production of a flowable mixture which reacts to form

The present invention is directed to a novel process and apparatus for charging a liquid reactant with a gas. In the process, the liquid reactant which is as yet uncharged with gas is introduced into the gassing tank at a point just below the substantially constant liquid level of the reactant. When the reactant has been charged with gas, it is removed at a point below the region where gassing takes place. A three-layered arrangement is thereby established and maintained in the gassing tank so that the layer of gas is separated from the layer of gas charged component by the layer of uncharged component. The gas charged component is thus maintained at a density corresponding to the desired gas content, taking into account any significant starting conditions, such as the original density, the temperature and the pressure. If necessary, this density is maintained by suitably varying the stirrer speed.

Process and apparatus for charging a liquid reactant with gas

The present invention is directed to a process for charging a component with a gas. The gas is metered through a hollow stirrer into the component to be charged with gas. The stirrer is operated at a higher gas throughput capacity than the amount of gas metered.

Process for charging at least one component with gas in the preparation

The present invention relates to an improved process for the production of a flowable mixture which reacts to form foam from flowable components stored in storage containers, wherein prior to metered introduction into a mixing zone, at least one of the components is charged with a defined quantity of gas, by (i) introducing said one component and gas separately into a gasification chamber equipped with a hollow stirrer, (ii) sucking gas into said component through the hollow shaft of the hollow stirrer, and (iii) stirring the gas into the component, until the desired value is attained, the improvement wherein (a) the component is circulated from the storage container through the gasification chamber and back into the storage container, (b) the gas sucked through the hollow shaft of the hollow stirrer being maintained at a pressure at least equal to the pressure prevailing in the storage container, and (c) the component fraction remaining in the storage container is homogenized during those periods in which gasification does not take place.

Process for the production of a flowable mixture which reacts to form

This invention relates to a process for the preparation of polyurethane foams by the reaction of a foamable reaction mixture. A liquid blowing agent is added to either the isocyanate or the polyol prior to mixing of the components. An inert gas is dispersed in the component which contains the blowing agent and the gas charged component is immediately and continuously mixed with the other component, at the same time keeping it at least under the pressure required for charging it with gas until mixing has been completed, and leaving the resulting reaction mixture to foam up. The key to the present invention is in the small amount of gas charging.

Process for the preparation of polyurethane foams

The present invention is directed to a process for the manufacture of molded parts having areas in the form of grids, grills or gratings, in which a fluid mass is introduced into the mold cavity of a molding tool conforming to the molded part and the cavity is filled by said fluid mass, characterized in that in the mold cavity, the zones provided for the apertures in the areas conforming to the said grids, grills or gratings of the molded part are first flooded by the mass and the mass is subsequently displaced from these zones, and to a molding tool to be used in such process.

Process and molding tool for the manufacture of molded parts having

A piston metering device for the production of a plastic material from at least two flowable reaction components. This device is basically composed of (a) a hydraulic driving mechanism, (b) two piston cylinder units, (c) a mixer head and, optionally, (d) a control device common to at least one of the piston cylinder units. This device permits rapid and simple adjustment of the metering ratio of reaction components by adjustment of throughput. Such adjustment is accomplished by means of regulating elements made of hydraulic motors rigidly coupled to one another.

Piston metering device for the production of plastic material from at

Apparatus for producing moldings from flowable reactive components comprising

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Leverkusen, Germany

Klaus Schulte