Abstract: Magnetic recording media possess, on a dimensionally stable base which may or may not be provided with a non-magnetic lower layer, a thin ferromagnetic metal layer on which a protective layer consisting of a silicon monoxide/chromium dual coating is applied.

Abstract: Magnetic recording media comprise a non-magnetic base and one or more magnetic layers consisting of an organic binder matrix containing finely divided magnetic material, the said matrix being obtained by electron beam curing of a mixture of from 70 to 90% by weight of a polyurethane acrylate polymer possessing polymerizable double bonds and from 10 to 30% by weight of one or more copolymerizable compounds.

Abstract: Novel 2-aminopyrazines and processes for the preparation of 2-aminopyrazines and pyrazines by reaction of an .alpha.-iminodiacetonitrile (a) with a hydrogen halide or (b) with an alcohol or a thioalcohol and a hydrogen halide or (c) with an alcohol or a thioalcohol in the presence of an alkali metal compound and/or an alkaline earth metal compound. The 2-aminopyrazines and pyrazines obtainable by the process of the invention are useful starting materials for the preparation of dyes, fungicides, bactericides, textile assistants, scents, folic acid derivatives, flavorings, and active ingredients in crop protection and drugs.

Abstract: A reel for material of tape-like configuration, especially magnetic tape, comprises two side flanges which are rigidly connected together to form a flange unit, and a hub firmly clamped between said side flanges. Advantageously, an essentially continuous gap is provided between the flange unit and the hub to accommodate any radial deformation of the winding surface. The novel reel is particularly suitable for computer and video tapes which exert considerable compression on the hub when they are wound.

Abstract: A process for depositing metals onto electrically conductive, polymeric carriers, wherein a finely divided metal M having a standard potential E.sub.o of >-2 V is deposited, from a solution of a metal cation compound of the formula (I) ##EQU1## where M', L.sup.1, L.sup.2, L.sup.3, L.sup.4, l, m, n, o, and p are as defined in the claims, in an aprotic polar or non-polar solvent, onto a polymeric, electrically conductive carrier of the formula (II) ##EQU2## where M" is Li, Na, K, Rb or Cs,P is P=--CH--, --C.sub.6 H.sub.4 --, --C.sub.4 H.sub.2 S--, --C.sub.6 H.sub.4 S--, --C.sub.4 H.sub.2 O--, --C.sub.4 H.sub.2 NH-- --C.sub.6 H.sub.4 O-- or --C.sub.5 H.sub.3 N--y is from 0.001 to 0.6 andx is from 5 to 1,000, or onto a polymeric, electrically conductive carrier of the formula (III)[(P)(X).sub.y ].sub.x (III)whereP is one of the groups listed for formula (II), X is ClO.sub.4.sup..crclbar., AsF.sub.6.sup..crclbar., PF.sub.6.sup..crclbar., SbF.sub.6.sup..crclbar., BF.sub.4.sup..crclbar., HSO.sub.4.sup..crclbar.

Abstract: Compounds of the general formula I ##STR1## where R is unsubstituted or substituted alkyl, alkenyl, aryl or hetaryl and R.sup.1 and R.sup.2 independently of one another are each unsubstituted or substituted alkyl or aryl, or, together with the nitrogen, form a heterocyclic ring, are prepared by a process wherein a compound of the general formula II ##STR2## is reacted with a water-soluble monohaloacetate in an aqueous alkaline medium. They are very useful coupling components for the preparation of azo dyes.

Abstract: A process for the preparation of dyes which contain sulfonic acid groups and have a low electrolyte content, wherein an aqueous solution or suspension, which may or may not contain inorganic salts, of the dye containing sulfonic acid groups is(a) mixed with an amount, equivalent to the said dye, of a non-emulsifying, water-insoluble amine of a total of 12 to 40 carbon atoms, which forms, with the said dye, a salt which is sufficiently lipophilic for it to separate spontaneously from the aqueous phase,(b) the pH is brought to <5 with an acid and the batch is mixed thoroughly,(c) the two resulting phases of different density are separated, and(d) the phase which consists of the lipophilic ammonium salt of the dye is mixed, with or without prior washing with water, with a water-soluble base whose sulfonate salt is to be prepared, and with water, the resulting phases are separated, and the salt is left in the aqueous solution or is isolated therefrom.

Abstract: Compounds which in the form of the free acids correspond to the formula ##STR1## where A is a radical of a diazo component or of an amine,B is a radical of a coupling component or of an aldehyde,R.sup.1 is chlorine or bromine,R.sup.2 is methoxy or ethoxy,X is .dbd.N-- or .dbd.CH--,Y is --O-- or --COO-- andZ is --O-- or --NH--,are dyes which are very suitable for dyeing nylons and natural polyamides.

Abstract: Dienes are prepared by dehydration of aldehydes at elevated temperatures by a method in which the dehydration is carried out using a zeolite as a catalyst.

Abstract: Crystallite suspensions containing from 3 to 70 weight percent of a crystalline, ethylenically unsaturated polyester prepared through condensation polymerization, and having a molecular weight factor per double bond of 154.4 to 408, as the dispersed phase, and from 30 to 97 weight percent of a polyhydroxyl compound having a functionality of from 2 to about 8, a hydroxyl number of from 20 to 800, and a melting point of less than 30.degree. C. as the coherent phase are suitable for preparing non-cellular and cellular polyurethane- or polyurethane group-containing polyisocyanurate foams.

Abstract: A curable composition consisting ofA. 100 parts by weight of an epoxy resin,B. from 4 to 100 parts by weight of a conventional curing agent for epoxy resins, andC. from 0.1 to 5 parts by weight of an N-acylimidazole which possesses an aromatic acyl component which is substituted at the two positions ortho to the carbonyl groupcan be used to produce moldings, coatings, finishes, adhesives and composite fiber materials.

Abstract: Magnetic recording media comprise a non-magnetic base and one or more magnetic layers consisting of an organic binder matrix containing finely divided magnetic material, the said matrix being obtained by electron beam curing of a mixture of from 50 to 100% by weight of a polyurethane acrylate polymer possessing polymerizable double bonds and from 0 to 50% by weight of an acrylate and/or an acrylate prepolymer and/or an N-vinyl monomer and/or an N-vinyl prepolymer.

Abstract: Electrophotographic recording materials which comprise an electrically conductive base, charge carrier-producing compounds or sensitizers, charge carrier-transporting compounds and added metal acetylacetonates and possess high photosensitivity and low conductivity in the dark are used for reprographic purposes and for the production of electrophotographic printing plates, in particular offset printing plates.

Abstract: Water-soluble copolymers which consist of from 40 to 90% by weight of one or more ethylenically unsaturated monocarboxylic acids of 3 to 5 carbon atoms, from 60 to 10% by weight of one or more ethylenically unsaturated dicarboxylic acids of 4 to 8 carbon atoms and/or of the corresponding dicarboxylic acid anhydride and, if required, not more than 15% by weight, based on the total weight of the carboxyl-containing monomers, of one or more carboxyl-free monomers, and which are esterified with from 2 to 60% by weight, based on the total weight of the carboxyl-containing monomers, of one or more compounds which contain a terminal hydroxyl group and one or more alkylene oxide groups of 2 to 4 carbon atoms, the preparation of such water-soluble copolymers and their use as assistants in detergents, cleansing and dishwashing agents.

Abstract: The invention relates to a heat-hardenable binder mixture which comprises(A) an organic nonacidic resin having a hydroxyl group content of at least 0.2 equivalent in 100 g of resin and having a molecular weight of at least 850, and(B) a crosslinking agent based on an organic compound which contains at least 2 carbalkoxymethyl ester groups per molecule.

Abstract: A sheet-like packing material consisting ofA. from 2 to 90% by weight of melamine resin or phenol resin fibers and/or fibrids,B. from 5 to 90% by weight of finely divided inorganic fillers, preferably cement, andC. from 2 to 40% by weight of organic binders, preferably rubber, with or withoutD. from 0.1 to 50% by weight of thermoplastic fibrids, the percentages summing to 100,possesses low gas permeability, high compressive creep strength and advantageous compressibility, resilience and swelling behavior.

Abstract: Isobutylene polymers are prepared continuously, in aliphatic C.sub.3 -C.sub.6 -hydrocarbons in the presence of soluble cationic polymerization initiators and coinitiators at from -40.degree. to 40.degree. C. and under from 0.01 to 10 bar, and the solvents and monomers vaporized during the polymerization are recycled, by a process in which the liquid stream of the monomer solution, containing 40-95, in particular 50-85, percent by weight of the monomers, the liquid streams of the recycle and of the coinitiator solution and the separate stream of the initiator solution are combined in a first zone containing the polymerization zone, and the resulting polymer solution is taken off continuously through a second zone vertically below the first zone. The liquid streams of the monomer solution, the coinitiator solution and the recycle can furthermore be fed into the first zone separately from one another.

Abstract: A gas-evolving metal electrode consists of profiles which are arranged parallel to one another in a horizontal plane and are connected to one another by means of current distributors. The profile surfaces which face the counter-electrode are curved, the curvature at the sides being more pronounced than that in the middle. The profile is terminated above by means of two lateral surfaces tangential to the curvature. The electrode is useful as an anode for mercury cells for the chloralkali electrolysis.

Abstract: A process for polishing the ground surfaces of magnetic storage disks which consist of a rigid substrate provided on both sides with a firmly adhering magnetic coating consisting of a magnetic material finely dispersed in an organic polymer and conventional additives, by pressing felt rings or felt disks against the moving magnetic storage disk, to the surface of which an aqueous emulsion containing butyl acetate with or without butane-1,4-diol is applied.

Abstract: A water-dilutable coating agent for preparing the base layer of a multilayer coating. The coating agent contains pigments and optionally flow-control agents, thixotroping agents, fillers, organic solvents and other customary auxiliaries.