Basf Aktiengesellschaft

Gerd Wunsch

Volker Kiener

Eberhard Koester

Paul Deigner

Werner Steck

Wolfram Treptow

Eduard Schoenafinger

Hans Henning Schneehage

Werner Ostertag

Werner Loeser

Erfried Voelkl

Rolf Wurmb

Karl Uhl

Fritz Beck

Siegfried Schreiner

Werner Stumpfi

Hugo Boehn

Hermann Meyer

Gotthard Csizi

Heinrich Adolphi

Helmut Jakusch

Bernd Leutner

Hermann Roller

Joachim Hack

Klaus Boehlke

Herbert Motz

Wolfgang Schwarz

Roland Falk

Franz-Josef Mueller

Uwe Stabel

Knut Bittler

Job-Werner Hartmann

Hans-Ulrich Schlimper

Joachim Stabenow

Eckhard Hetzel

Peter Felleisen

Friedrich Domas

Manfred Steuerwald

Werner Senkpiel

Dietmar Werner

Hans Roos

Karl Mahler

Franz L Ebenhoech

Helmut Woerz

Andreas Fried

Ruediger Kotkamp

Theodor Mader

Dieter Graw

Henning Schneehage

Friedrich Fuchs

Hartwig Koester

Rudi Waibel

In a process for the recovery of a polymerizable useful fraction, consisting of styrene, methylstyrenes, vinyltoluenes, indene, methylindenes and fractions whose boiling points are between styrene and methylindenes, from the crack gases of a steam cracker, the sidestream of the crack gas column is divided, by means of a distillation unit, into the useful fraction and into fractions which are recycled to the crack gas column.

Recovery of a useful polymerizable fraction

In an electrode suitable for electrolysis of aqueous sodium chloride or potassium chloride solutions, at least the outer layer contains spinels, specifically a mixture of the individual spinels of iron and of cobalt, the weight ratio of iron spinels: cobalt spinels being from 30:70 to 90:10. The electrodes are produced by applying a powder mixture of iron spinel and cobalt spinel to a substrate by a plasma spraying process wherein argon is used as the plasma gas and the spraying energy is from 6 to 30 kW.

Spinel-containing electrode and process for its production

A process for the manufacture of wear-resistant magnetic recording media comprising a dimensionally stable base, a thin ferromagnetic metal layer, containing cobalt and/or nickel, firmly bonded thereto and a thin protective layer applied thereon. The protective layer is produced by treating the recording medium in a liquid basic medium, containing gaseous oxygen, for from 1 to 60 minutes at from 5.degree. to 70.degree. C., washing and drying the treated recording medium and then heating it in air at from 170.degree. to 300.degree. C. This method offers a particularly simple way of providing the ferromagnetic layer of the recording medium with a thin but uniform, mechanically stable and wear-resistant protective layer.

Manufacture of magnetic recording media having a wear-resistant surface

In a process for the manufacture of sodium dithionite by reacting sulfur dioxide with sodium formate and aqueous sodium hydroxide solution in the presence of methanol, an aqueous methanolic solution of sodium formate is first produced by reacting carbon monoxide with sodium hydroxide solution in an aqueous medium, containing from 1 to 50% by weight of methanol, based on the amount of water, at from 80 to 120.degree. C. under a pressure of from 10 to 40 bars. The resulting aqueous methanolic solution can be reacted directly, in the conventional manner, with sulfur dioxide and aqueous sodium hydroxide solution to give sodium dithionite.

Manufacture of aqueous methanolic solution of sodium formate

In an electrolysis cell with anodes and cathodes which are provided with openings, the cathode chamber is separated from the anode chamber by a diaphragm. The latter consists of a porous layer of oxides or oxidic compounds of the elements of sub-group 4B of the periodic table, of aluminum, of the rare earths or of chromium. The diaphragm is applied to that side of one of the electrodes which faces the counter-electrode.

Electrolysis cell

Manufacture of electrodes consisting of bases of valve metals with electrochemically active coatings applied thereto. The electrodes are pre-treated before the said coatings are applied, the pre-treatment comprising treating the base with hydrogen.

Manufacture of electrodes

Finely divided metal oxides produced by combustion of metal carbonyls are separated from the stream of gas by filtration. Before filtration, the stream of gas is subjected to a permanent change of direction in a tubular zone. This change of direction must be sufficient to cause a centrifugal acceleration which is from at least 1,000 to 10,000 times the acceleration due to gravity.

Separation of finely divided metal oxides, produced by combustion of

A process for the manufacture of rigid magnetic recording media by depositing a cobalt-containing ferromagnetic metal layer on a non-magnetic metallic base disc provided with a cured layer of binder which does not dissolve or swell in organic solvents and contains non-magnetic pigments, and which has been activated, before deposition of the ferromagnetic layer, by treatment with a solution of a palladium (O) complex in an organic solvent, followed by decomposition of this complex, to prepare it to receive the ferromagnetic metal layer which is produced by electroless deposition.

Process of making a magnetic recording medium

An accumulator having an acid electrolyte and possessing two electrodes of the first kind mounted on base electrodes. The active material on the positive side contains manganese dioxide. The base electrode on the negative side consists of powdered graphite embedded in a binder which is resistant to the electrolyte. The base electrode on the positive side has a coarse porous structure and consists of graphite or titanium coated with titanium nitride or titanium carbide. The average pore diameters are from 0.1 to 2 mm and the pore volume is from 20 to 70%.

Rechargeable accumulator having a manganese dioxide electrode and an

Accumulators having solution electrodes containing manganese dioxide and lead dioxide as active material on the cathode side and containing acid electrolytes. The electrolyte has a content of onium salts soluble in aqueous medium.

Accumulator equipped with cathodes of manganese dioxide or lead dioxide

A method of stabilizing pyrophoric metal powders by treating the metal powders with alkylene oxides to form a polymer coating on the metal particles.

Stabilization of pyrophoric metal powders with alkylene oxide polymers

A process for the manufacture of acicular gamma-iron(III) oxide, in which the non-magnetic, acicular iron(III) oxide is treated with a solution of a compound of the formula I ##STR1## where R.sup.1 and R.sup.2 are ##STR2## or O--R.sup.5, R.sup.3 is H, OH, ##STR3## or O--R.sup.5, R.sup.4 is alkyl or cycloalkyl of 1 to 16 carbon atoms and the R.sup.4 's may be identical or different, and R.sup.5 is alkyl, cycloalkyl or aralkyl of 3 to 18 carbon atoms, and is then converted to gamma-iron(III) oxide by reduction to magnetite, followed by oxidation. The gamma-iron(III) oxide obtained is distinguished by a high coercive force and improved magnetic orientation when used as a magnetic pigment for the manufacture of magnetic recording media.

Manufacture of gamma-iron(III) oxide

An anode for electrochemical processes consists of an electrode base plate of a metal which can be passivated electrochemically, a protective layer deposited thereon, and a further layer, consisting of manganese dioxide. The protective layer consists of the nitride of the metal of the electrode base plate.

Anode for electrochemical processes

A process for the manufacture of acicular ferromagnetic metal pigments containing iron, having a reduced field strength distribution and a steeper residual magnetization curve, by applying equivalent amounts of an alkaline earth metal cation and of a monobasic, dibasic or tribasic aliphatic carboxylic acid of up to 6 carbon atoms onto appropriate acicular iron oxides and then reducing the treated oxides.

Manufacture of ferromagnetic, acicular metallic iron particles by

Magnetic recording tape especially suitable for use as video tape and computer tape, comprising a base carrying a magnetic coating which consists essentially of a dispersion of a finely divided magnetic pigment and at least one lubricant in an organic binder. The lubricant is a compound of the formula ##STR1## IN WHICH N IS AN INTEGER OF FROM 3 TO 8 AND R.sup.1 and R.sup.2 are an alkoxy or aralkoxy radical or conjointly are an alkyldioxy radical of 3 to 18 carbon atoms. A magnetic recording tape prepared with a high proportion of such a lubricant is distinguished by high abrasion resistance coupled with a minimum transfer of material to the magnetic heads even under fluctuating climatic conditions.

Magnetic recording tape

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Speyer, Germany

Gerd Wunsch