Abstract: A magnetic tape cassette comprises a housing open on one side and, movable therein, a sheath enclosing a magnetic tape roll. Detachable retaining means in the cassette hold the sheath and the roll in position while the cassette is not on the recorder. The retaining means are detachable by unlatching means when the cassette is fitted to the recorder, so that, following a movement of the sheath, the cassette is opened to allow the roll to emerge at least partially from the cassette and the circumference of the roll to be rotated by means of a recorder-associated capstan provided outside the cassette. Further advantageous embodiments of the invention concern the cassette and the recorder. The cassette of the invention and the recorder associated therewith can be employed in all fields of magnetic tape recording and reproduction. Its application to a magnetic tape system with a self-threading tape end entails advantages.

Abstract: A process for the manufacture of thin layers based on polyurethane elastomers. A liquid reaction mixture essentially consisting of (A) polyesters, polyethers, polyester urethanes or polyether urethanes, all of which contain at least two hydroxyl groups in the molecule, and diisocyanates or (B) prepolymers obtained from the hydroxyl-containing compounds mentioned under (A) above with an excess of diisocyanates, said prepolymers containing at least two isocyanate groups in the molecule, and at least one of the compounds mentioned under (A) above which are capable of reacting with isocyanates, to which reaction mixture a minor quantity of substantially compatible monomers having at least two photocrosslinkable C--C multiple bonds and optionally a photopolymerization initiator have been added, is applied to a substrate to form a coating thereon, which coating is then gelled by irradiation and finally thermocured.

Abstract: Manufacture of insoluble polyvinyl lactams in the absence of oxygen and in the presence of .alpha.- or .beta.-ketocarboxylic acids or esters thereof.

Abstract: Gas mixtures containing ammonia and carbon dioxide are separated by fractional absorption in a solvent. The gas mixture and solvent are intimately mixed in a zone, the residence time of the gas in the mixing zone being restricted to a maximum of 0.1 second. Non-absorbed gas and solvent are then separated from one another and the gas separated off is subjected to a further absorption if necessary.

Abstract: Polymers which contain hydroxamic acid-O-sulfonyl groups in the side chains and which accordingly can undergo important substitution reactions. The polymers may also contain other reactive groups and may be used for the manufacture of moldings, coatings or adhesives.

Abstract: Hydrophobic diaphragm material, such as crystalline, highly expanded microporous polytetrafluoroethylene film, may be prepared for installation in a chlor-alkali cell by a process involving the steps of (1) immersing the diaphragm in a solution of acetal-type nonionic surfactant in a suitable non-aqueous solvent, (2) rinsing the diaphragm in deionized water, (3) immersing the diaphragm in an aqueous solution containing an amount of acetal-type nonionic surfactant effective to promote wetting for a suitable period of time, and (4) immersing the diaphragm in a brine solution containing about 100 to 200 grams per liter of sodium chloride and an amount effective to promote wetting of an acetal-type nonionic surfactant for a suitable period of time, such as several hours. In some instances, it is also advantageous to subject the diaphragm while immersed in the solvent solution to the action of a vacuum, to release trapped air.

Abstract: In the process of producing chlorine and caustic soda employing mercury amalgam electrolytic cells, mercury losses occur in both solid and liquid plant waste streams. This invention provides for an integrated system in which mercury is extracted from plant waste streams, the waste streams are discharged, and the mercury recovered by electro-reduction in the plant electrolytic cells.

Abstract: An improved method of removing heat from polymerization reactions of normally gaseous monomers in the gas phase comprising feeding the monomer in liquid form to a polymerization zone, immediately after entering said zone, removing a portion of said gaseous monomer from the polymerization zone, liquefying said portion of monomer by cooling it at the same pressure as that prevailing in the polymerization zone, recycling the liquefied monomer to the polymerization zone together with fresh monomer in liquid form and causing said liquid monomer to change to the gaseous form immediately after entering said zone. The improvement consists in not only condensing the monomer outside the polymerization zone but also storing the same, in keeping the temperature in the polymerization zone constant by regulating the rate at which liquid monomer is fed to the zone, and in keeping the temperature and pressure in the polymerization zone within limits conducive to the gaseous state of the monomer.

Abstract: New pyridazinium compounds which can be used as intermediates and are of interest because of their pharmacological properties, and their production.

Abstract: Electrochemical manufacture of aromatic esters of the naphthalene series by acylation of naphthalene derivatives in an alkanoic acid, wherein the electrolysis is carried out in the presence of a conducing salt of the formula[R.sup.1 R.sup.2 R.sup.3 NH] .sup.+ [OOCR.sup.4 ].sup.-in which R.sup.1, R.sup. 2 and R.sup.3 denote hydrogen and/or alkyl and R.sup.4 denotes hydrogen or alkyl of from 1 to 6 carbon atoms.

Abstract: Fluid photo-crosslinkable composition consisting essentially of a photo-initiator and a mixture ofA. a polyurethane obtained by reacting a hydroxyl-containing saturated aliphatic polyester with a polyisocyanate and a monoacrylate or monomethacrylate of a diol, andB. an N-vinyl lactam optionally in admixture with other monomers.These compositions are suitable for the production of high-quality relief printing plates and have a short processing time.

Abstract: 3-(P-Biphenylyl)-butyronitrile, its production and its use as an antiphlogistic agent.

Abstract: To obtain nonionic surfactants having solubility and stability in relatively strong aqueous solution of caustic, salt or other electrolytes, corn starch or a similar source of glucose units is reacted with an alcohol containing up to about 4 carbon atoms to obtain a glycoside somewhat more lipophilic than the saccharide, and then the resulting glycoside is reacted with a hydrophobic oxirane-containing material such as a C.sub.6 to C.sub.18 epoxyalkane or a glycidyl ether having about the same number of carbon atoms.

Abstract: A levelling auxiliary for dyeing fibrous material of polyamide fibers with acid dyes in the acid pH range in the presence of a mixture which contains (based on the solids in each case) from 30 to 90% by weight of a surfactant having sulfonic acid groups and from 10 to 70% by weight of an oxyethylated polyamide which has been prepared by the reaction of 1 part by weight of polyamide with from 2.5 to 3.5 parts by weight of ethylene oxide. Level dyeings devoid of streaks are obtained.

Abstract: The production of formaldehyde by oxidizing dehydrogenation of methanol in the presence of a silver catalyst which consists of three or more layers each of specific weight and particles of specific particle size and having a specific total layer thickness. Formaldehyde prepared according to the process of the invention is a disinfectant, tanning agent, reducing agent and valuable starting material for the production of synthetic resins, adhesives and plastics.

Abstract: A process for the manufacture of thiophen-3-aldehyde, in which a 2,5-dialkoxy-3-formyl-tetrahydrofuran is reacted with hydrogen sulfide in the presence of a strong acid, at temperatures of from 50.degree. to 320.degree. C.

Abstract: Condensation products of derivatives of naphtholactam and barbituric acid useful as dyes for synthetic fibers, particularly synthetic linear polyesters, and for coloring resins. The dyes give brilliant yellow to violet shades having outstanding fastness properties.

Abstract: Spherical refining catalysts containing cobalt and/or nickel together with molybdenum on aluminum oxide are prepared in closed mixers provided with mixing elements from spray-dried powders such as catalyst preparations or carriers using peptizing agents. The catalysts thus prepared have a bulk density much higher than that of extrudates of similar composition. Their surface and pore size distribution make them suitable for use in the catalytic refining of hydrocarbon fractions containing metal and asphalt, and particularly for refining vacuum distillates and residues from atmospheric distillation.

Abstract: Basic carbonate which contains copper and aluminum and is suitable for the manufacture of copper-containing catalysts and which has the general formula Cu.sub.m Al.sub.6 (CO.sub.3).sub.0.5m O.sub.3 (OH).sub.m.sub.+12, where m may be an integer or non-integer between 2 and 6.

Abstract: Bisstyryl-substituted aryl compounds of the formula (I): ##STR1## where X is arylene and R.sup.1 and R.sup.5 are substituents common to the dye art. The compounds are useful as optical brighteners, particularly for acrylonitrile polymers, and give excellent whitening having good fastness properties.