Bayer Aktiengesellschaft

Rudolf J Klee

Hans-Josef Buysch

Gerhard Darsow

Edgar Muschelknautz

Heiko Herold

Christine Mendoza-Frohn

Ulrich Notheis

Richard Herold

Ralf Miessen

Theo Neukam

Gunter Turck

Herbert Schmidt

Ferdinand Kummeler

Joachim Kolbe

Jurgen Scharschmidt

Hans Kaloff

Hans Bach

Hans-Dieter Jurischka

Gerd Arenz

Karl-August Heinroth

Herbert Scherzberg

Wilfried Naunheim

J Urgen Scharschmidt

A description is given of the preparation of hydroxybiphenyl by dehydrogenation of completely or partially hydrogenated precursors using a supported Rh catalyst which additionally contains chromium, manganese and alkali metal and can contain a sulphur compound. The Rh catalyst which can be used according to the invention is prepared from halide-free starting materials. The Rh catalyst is distinguished by a low dependence of the initial selectivity, with the selectivity in the run-in state and the running-in time on the conditions of the reductive pretreatment and requires only short running-in times to reach the optimum state.

Process for preparing hydroxybiphenyl

The preparation of optionally substituted diphenylamine by reaction of optionally substituted aniline with optionally substituted cyclohexanone using a supported Rh catalyst containing rhodium or a combination of rhodium with another platinum metal from the group of palladium, platinum, ruthenium or iridium and which can additionally contain chromium, manganese, alkali metal and a sulphur compound is described. The catalyst of the invention is prepared from halide-free starting materials. The Rh catalyst is distinguished by a low dependence of the initial selectivity, the selectivity in the run-in state and the running-in time on the conditions of the reductive pretreatment and requires only short running-in times to the optimum state.

Process for preparing diphenylamines and catalysts usable for this

The process for production of polyacrylonitrile hollow threads with a stable, asymmetric pore structure by a dry-wet-spinning process with glycerine-based core liquids, definite draw and after treatment conditions and a treatment with alcohols and drying.

Method of preparing polyacrylonitrile hollow threads with asymmetric

The invention relates to new finishing mixtures, which contain fatty acid alkanolamides having softening points above 70.degree. C. as anti-blocking components, for synthetic fibers, particularly fibers of polyacrylonitrile, which are used as staple fibers. The invention also relates to the use of these finishing mixtures for the finishing of staple fibers, particularly polyacrylonitrile-based staple fibers.

Finishes for stable fibers of synthetic polymers

A liquid jet, which is not decomposed to droplets, is guided onto a hot yarn wad in a cooling section with rod guide means, and this leads to rapid, very uniform cooling. Smooth thread travel is produced during take-off at thread speeds of 2000 m/min and more. One deflection of the thread is usually sufficient for drying purposes since the liquid is thereby centrifuged off.

Method of cooling stuffer crimped yarn

An airstream impinging laterally on a thread can convey a running thread through an opening. This 'placing' of threads in nozzles fails at elevated thread speeds. According to the invention, placing succeeds even at high thread speeds if a strong stream of propelling gas is divided in the nozzle into edge streams which are deflected outwards and a fine central stream which conveys the thread through the narrow opening.

Method and apparatus for placing thread in a texturing apparatus at

The invention is related to a process for the stretch-texturing of high-molecular weight linear synthetic endless filaments travelling at speeds of 300 to 1200 meters per minute by continuously guiding the filaments through a delivery zone, a heat-fixing zone, a false-twister and a stretching godet. The endless filaments are passed through a stretching zone S 55 to 180 cm long, defined by the distance between the delivery stage and the stretching godet, the distance between the delivery stage and the false-twister inlet amounting to S-X cm and the distance X between the false-twister outlet and the stretching godet being 5 to 30 cm.

Process for the production of synthetic endless filaments with good

The invention is related to a process for the production of staple-fibre-like textured continuous filament yarns by interlacing and false-twisting, wherein a partly drawn filament is heat-treated before the texturing process, this filament is subsequently interlaced with a non shrunken filament and both are finally subjected to draw texturing.

Process for the production of textured filament yarns with the

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Dormagen, Germany

Rudolf J Klee