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

Abstract: Magnetic recording media comprising a base and, applied thereto, at least one firmly adhering magnetic layer based on magnetic particles dispersed in a mixture of organic binders, wherein at least the uppermost magnetic layer additionally contains non-magnetic particles of precipitated silica having a primary particle diameter of from 0.02 to 0.1.mu., a secondary particle diameter of from 2 to 4.mu. and a pH of from 5 to 8.As a result of the incorporation of such a precipitated silica into the magnetic layer, the coefficient of friction between the latter and metals remains uniformly low even after prolonged use, and no stick-slip motion occurs.

Abstract: A process for the manufacture of heat-stable, brominated oligostyrenes by brominating selectively hydrogenated oligostyrenes in halogenated solvents in the presence of Lewis acids at from -25.degree. to +20.degree. C. The brominated oligomers are highly heat-stable and can be processed, by themselves or as components of mixtures with other thermoplastics, to give various shaped articles.

Abstract: Apparatus for the manufacture of the magnetic coatings of magnetic disks consisting essentially of a clamp/drive unit for the base plate to be coated, a unit for applying the magnetic dispersion, and flat covering elements which rotate during centrifuging of the coated base plate in the same direction as said base plate and at a short distance from the surfaces thereof.

Abstract: Ethylene polymers are manufactured by polymerizing ethylene under high pressure at high temperatures in an autoclave reactor. The heat of reaction generated by the polymerization is removed, within the reactor, by a cooling system in which the cooling medium is ethylene; the pressure of the monomer in the cooling system should differ by from 0 to 200 bars from the pressure prevailing in the polymerization system, and the temperature of the monomer on entering the cooling system is at least 40.degree. C. lower than the temperature prevailing in the autoclave. The process permits an increase in the conversion achieved in the polymerization reaction.

Abstract: Mineral lubricating oil compositions which contain a predominant proportion of a mineral lubricating oil together with a pour point depressant based on alkyl acrylate or alkyl methacrylate polymers and a viscosity index (VI) improver comprising a special selectively hydrogenated copolymer of styrene and a conjugated diene. The VI improver employed is a selectively hydrogenated, random butadiene-styrene copolymer containing from 35 to 45% by weight of styrene and possessing a particular structure and distribution of the monomers. The compositions exhibit high stability to shear and may therefore in particular be used for lubricating I.C. engines or gearboxes.

Abstract: Auramine salts having an ester of sulfopropionic acid as anion. The salts are more stable in storage than known auramine salts and therefore very suitable for the preparation of storage-stable solutions.

Abstract: Multi-block coupled polyoxyalkylene copolymer surfactants are prepared from individual blocks of polymers and copolymers of alkylene oxides by reacting these with bifunctional compounds to form polycarbonate esters and polyformals.

Abstract: Compositions of vanadyl alcoholate, organic titanate and polyhydric alcohol compounds are effective esterification and transesterification catalysts.

Abstract: An improved catalyst for the complete hydrogenation of acetylenically unsaturated alcohols and based on nickel, copper and manganese. The catalyst is used without a support and molybdenum is additionally included in an amount approximately equal to the content of manganese.

Abstract: Formaldehyde is prepared by oxidative dehydrogenation of methanol in the presence of a silver catalyst, specific amounts of steam and specific amounts of an off-gas, of a specific composition, taken from the manufacture of formaldehyde. The reaction is started at a lower throughput of methanol and at a lower temperature. The formaldehyde obtainable by the process is a disinfectant, tanning agent and reducing agent, and a starting material for the manufacture of synthetic resins, adhesives and plastics.

Abstract: Polyester fibers are dyed with disperse dyes at temperatures above 100.degree. C. in an aqueous liquor containing, as leveling agents, emulsions of aliphatic esters, nitriles or ketones each containing from 7 to 16 carbon atoms, level shades being obtained.

Abstract: An apparatus for guiding a span of high speed magnetic recording tape past a recording/transducing head. Pressurized air is utilized to lift the tape off of the guide thereby eliminating sliding friction between the apparatus and the tape. In addition, a pair of beveled flanges are provided on opposite sides of the path followed by the tape as it is transported, which are spaced apart at their base a distance less than the minimum width of the tape. In operation, an air film of substantially constant pressure is generated along the air chamber formed by the tape, guide, beveled flanges and tangent points where the tape enters and exits from the guide sufficient to lift the tape off of the guide to a point where its width substantially equals the horizontal distance between the beveled flanges, thereby maintaining the tape in a centered relationship with respect to the center line of the guide and impeding the airflow about the lateral edges of the tape.

Abstract: 1-Alkylcarbamoyl-3-(3,5-dichlorophenyl)-hydantoins and a method of combatting unwanted phytophathogenic fungi with these compounds.

Abstract: Pent-4-en-1-al is manufactured by passing an acetaldehyde-acetal of the general formula ##STR1## where R is allyl or alkyl of 1 to 3 carbon atoms, in the gas phase and at from 350.degree. to 450.degree. C, over an active-surface catalyst.

Abstract: 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.

Abstract: Cyclopentene derivatives (I) ##STR1## where R.sup.1 is isopropyl or isopropenyl, R.sup.2 is alkyl of 1 to 3 carbon atoms, X is --CHO, a dialkyl acetal or 1,2- or 1,3-alkylene acetal thereof where the acetal radical is of 2 to 6 carbon atoms, --CH.sub.2 OH or --CH.sub.2 OCOR.sup.3 where R.sup.3 is hydrogen or alkyl or alkenyl of up to 3 carbon atoms. The manufacture of I from the corresponding halomethyl cyclopentenes and aldehydes R.sup.2 --CH(CH.sub.3)--CHO in the presence of a base and a quaternary ammonium salt, followed if desired by acetalization or conversion of the --CHO group to the --CH.sub.2 OH or --CH.sub.2 O--CO--R.sup.3 groups. The compounds are useful as fragrance materials.

Abstract: A phthalocyanine formulation which is stabilized against recrystallization and change of modification and which contains, as the stabilizer (a) a finely divided phthalocyanine as the pigment and (b) a salt or the corresponding homogeneous mixture of (.alpha.) a phthalocyanine derivative, which carries basic groups ##STR1## (R.sup.1 = H, alkyl of 1 to 20 carbon atoms, unsubstituted or substituted phenyl, --C.sub.2 H.sub.4 --NH).sub.z H or --(C.sub.3 H.sub.6 --NH).sub.z H, z = 1, 2 or 3, and R.sup.2 = H, alkyl of 1 to 6 carbon atoms or cycloalkyl of 6 to 8 carbon atoms) and (.beta.) an aliphatic sulfonic acid of 8 to 20 carbon atoms, a monoalkylbenzenesulfonic acid or dialkylbenzenesulfonic acid where alkyl is of 6 to 20 carbon atoms, or a monoalkylnaphthalenesulfonic acid or dialkylnaphthalenesulfonic acid where alkyl is of 6 to 20 carbon atoms, which acids may be substituted by hydroxyl, the molar ratio of .alpha.:.beta.

Abstract: A process for the manufacture of aliphatic isocyanates by thermal decomposition of aliphatic carbamic acid halides. The decomposition is carried out in stages and the hydrogen halide liberated is expelled, in the first stage, without passing inert gas through the reaction mixture, while in the second stage it is expelled while passing an inert gas, which is recycled, through the reaction mixture.

Abstract: In a process for the manufacture of polychloro-copper phthalocyanines by chlorinating copper phthalocyanines in aluminum chloride/sodium chloride melts at from 110.degree. to 190.degree. C, the improvement wherein from 0.20 to 0.33 part by weight of copper phthalocyanines, per part by weight of melt, is rapidly introduced into the melt at temperatures from the solidification point of the melt to 120.degree. C, and after this material has been introduced, the chlorination, to give polychloro-copper phthalocyanine, is carried out at from 140.degree. to 160.degree. C by rapidly passing chlorine into the mixture. A polychloro-copper phthalocyanine which contains less than 0.05 per cent by weight of aluminum and which can be converted, by any conventional finishing process, into yellowish green pigment forms, is obtained with high space-time yield.