Abstract: Multilayer interference pigment consisting of plateletlike titanium dioxide as carrier material, coated with alternating layers of metal oxides of low and high refractive index, the difference in the refractive indices being at least 0.1, which is obtainable by solidification and hydrolysis of an aqueous solution of a thermally hydrolysable titanium compound on a continuous belt, detachment of the resulting coat, coating of the resulting titanium dioxide platelets, with or without drying in between, by a wet method with, alternately, a metal oxide hydrate of high refractive index and a metal oxide hydrate of low refractive index by hydrolysis of the corresponding, water-soluble metal compounds, separation, drying and, if desired, calcining of the material obtained.

Abstract: Multilayer interference pigment consisting of a central layer of a transparent or semitransparent material of low refractive index and alternating layers of a metal or of a material of high refractive index and of a material of low refractive index either side of the central layer, the material of low refractive index preferably being magnesium fluoride or acrylate and the metal preferably being aluminium or chromium.

Abstract: Multilayer interference pigment consisting of a central, absorbing layer and alternating layers of a material of low refractive index and of a metal or of a material of high refractive index either side of the central layer, the material of low refractive index preferably being acrylate and the metal being aluminium or chromium. The absorbing layer consists of a coating system which comprises carbon black or color-imparting absorption pigments.

Abstract: Plateletlike titanium dioxide reduction pigment consisting of titanium dioxide, titanium suboxides and, if desired, a further metal oxide or titanium oxynitride, obtainable by solidifying an aqueous solution of a thermally hydrolysable titanium compound on a continuous belt, detaching the resulting coat, coating the resulting titanium dioxide platelets, with or without drying in between, with further titanium dioxide by a wet method, drying and, if desired, calcining the material, and treating the material obtained with a reducing agent in a nonoxidizing gas atmosphere.

Abstract: Single-layer or multilayer titanate-containing pearlescent pigments comprising iron titanate and, if appropriate, titanium oxide and/or iron oxide, which is obtainable by solidification of an aqueous solution of a thermally hydrolysable titanium compound on a continuous belt, detachment of the layer formed, coating of the resulting titanium dioxide platelets, after or without intermediate drying, with iron oxide in a wet process, and drying and calcining of the resulting material in an oxidizing or reducing gas atmosphere at not less than 500.degree. C., the layer thicknesses of the titanium dioxide layer and iron dioxide layer being adjusted such that either the stoichiometric ratio between iron oxide and titanium dioxide necessary for the formation of pseudo-brookite or ilmenite is obtained or an excess of iron oxide or titanium dioxide is present.

Abstract: The invention relates to electrically conductive pigments which as a conductive layer on a platelet-shaped or needle-shaped substrate have a niobium- and/or tantalum-doped tin oxide or titanium dioxide layer.

Abstract: Plateletlike, substrate-free titanium dioxide pigment obtainable by solidifying an aqueous solution of a thermally hydrolyzable titanium compound on a continuous belt, detaching the resulting layer, coating the resulting titanium dioxide platelets, with or without drying in between, with further titanium dioxide by a wet method, and separating off, drying and calcining the material obtained.

Abstract: The invention relates to carbon-containing pigments having improved abrasion resistance and dispersibility and to their production.

Abstract: Tin-containing grey pigments of high opacity, processes for their preparation and use thereof.

Abstract: Gold pigments of high opacity and processes for their preparation and use.

Abstract: A stabilized conductive pigment based on aluminum-doped zinc oxide which, for stabilizing the electric conductivity, contains an alkaline earth metal titanate or an oxide of an element from group III or IV.

Abstract: Substrate-free electrically conductive pigment containing 90 to 98% by weight of tin oxide and 1 to 10% by weight of at least one doping substance consisting of an oxide of an element form main group III, IV or V of the Periodic Table with the exception of tin, which pigment is preparable by intimate mixing of tin dioxide with at least one doping substance, followed by calcining of the resulting mixture at 800.degree. to 1,000.degree. C. for 30 to 120 minutes.

Abstract: A process for the preparation of light-colored, electrically conductive pigments based on substrates having an expansion of not more than 500 .mu.m, which pigments consist of one or more metals, metal oxides or materials containing metal oxide, silicon oxide or silicate materials and contain, if desired above one or more other metal oxide and/or silicon oxide layers, an outer layer based on halogen-doped tin oxide and/or titanium oxide.

Abstract: There is disclosed an electrically conductive pigment containing 20 to 95% by weight of a component A comprising one or more conductive platelet-like pigments and 5 to 80% by weight of a component B comprising one or more conductive needle-shaped or fibrous pigments.

Abstract: The invention relates to a pigment containing carbon black having improved abrasion resistance comprising a platelet-shaped substrate coated with a metal oxide layer containing carbon black, wherein the carbon black is fixed on the substrate by means of an anionic or cationic and a nonionic surfactant and an organosilane compound.

Abstract: A screw-type extruder has a housing and at least one screw which is rotatably arranged in a bore in the housing and which conveys material while melting or plasticizing in a conveying direction to a discharge channel, a starting valve and a throttle for generating a back pressure on the molten or plasticized material being arranged in the area of the discharge channel. In order to avoid long flow paths of the molten or plasticized material via the throttle and starting valve, there is provided a starting valve/throttle unit having a starting valve and throttle body which is displaceable at right angles to the conveying direction out of a starting position into a throttling position.

Abstract: An extractor for removing worm elements which are fastened for rotation on the worm shaft of a worm extruder wherein a frame formed of longitudinal and cross members has a locking device in one of the cross members for holding the worm elements and an opposed, displaceable, pneumatic piston-cylinder unit on another cross member. The piston-cylinder unit has a pressure piston which is extendable axially towards the worm shaft. Between the worm shaft and the piston-cylinder unit is a slide which is displaceable longitudinally and can be engaged by the piston of the piston-cylinder unit. The slide carries an impact device which is pneumatically actuatable and includes an impact shaft for engaging the worm shaft. The locking device includes two clamp jaws which are axially aligned with the impact shaft and the piston and engage the worm profile with an inner profile surface of identical type.

Abstract: A system for forming address signals which address respective converter switches in a frequency converter. The frequency converter is of the type wherein a DC voltage is provided for supplying electrical energy to phase outputs thereof in response to the states of the converter switches. In accordance with the invention, the phase output voltages, phase output currents, and predetermined desired phase currents are treated as space vectors from which are generated control difference space vectors. In one embodiment, a trigger pulse is generated externally and may be suppressed when the control difference vector has a value which is below a preselected tolerance limit. In a further embodiment, the trigger pulse is generated internally and is suppressed if the tolerance limit is exceeded. Upon the occurrence of each trigger pulse, a voltage space vector is addressed having a direction which is opposite to the control difference space vector.

Abstract: A system for forming addressing signals for addressing respective converter switches of a frequency converter; the frequency converter being of the type which is provided with DC input terminals for receiving electrical energy which is conducted to phase output terminals when the converter switches are operated in response to the addressing signals. Each of the combinations of converter switches is associated with a discrete space vector, and a load voltage vector is determined. In operation, two of the discrete space vectors which are adjacent to the voltage space vector are addressed for respective dwell times which correspond to the components of the voltage space vector as impressed upon the adjacent discrete space vectors. Either prior to or after the addressing of the adjacent discrete space vectors within a switching cycle, a short circuit state is addressed. In one embodiment, the order in which the adjacent discrete space vectors are addressed is reversed for each subsequent switching cycle.