Bayer Aktiengesellschaft

Joachim Dross

Ulrich Reinehr

Toni Herbertz

Rolf-Burkhard Hirsch

Hermann-Josef Jungverdorben

Hermann J Jungverdorben

Hans K Burghartz

Herman-Josef Jungverdorben

A process for the production of crimped filaments and fibers of acrylonitrile polymers of copolymers containing at least 40% by weight acrylonitrile units, by dry spinning from highly polar solvents, where the filaments are brought to extremely low solvent contents in the actual spinning tube by a minimum of superheated steam prepared in the absence of water at very high spinning tube temperatures and spinning gas temperatures, but are cooled to low filament temperatures in the spinning tube by application of water or aqueous finishes in a quantity equivalent to more than 10% by weight moisture. In this way, spun PAN filaments of good natural color are safely obtained, in which there is no washing stage and no drying stage. Acrylic fibers and filaments combining a vacuolestable structure with a very high degree of whiteness and gloss are thus obtained with densities of at least 1.180 g/cm.sup.3, giving shrinkage-free to high-shrinkage fibers, depending on the aftertreatment applied.

Continuous production of acrylonitrile filaments and fibers from

Thread bundles which are transported from top to bottom, can be wetted with liquids by means of a device consisting of a system releasing the liquid, conduits and a storage container as well as suitable transporting means for the liquid, whereby the system releasing the liquid has at least two slotted nozzles positioned one above the other and opposite each other, having a horizontal slot and whereby rods are attached at the slot ends which, seen from above, form an angle with the slot of from 100 to 170.degree., preferably from 115 to 160.degree..

Process for wetting thread bundles with liquids

Threads, films or thread bundles which are transported from top to bottom, can be wetted with liquids by means of a device consisting of a system releasing the liquid, conduits and a storage container as well as suitable transporting means for the liquid, whereby the system releasing the liquid has at least two slotted nozzles positioned one above the other and opposite each other, having a horizontal slot and whereby rods are attached at the slot ends which, seen from above, form an angle with the slot of from 100.degree. to 170.degree., preferably from 115.degree. to 160.degree..

Device for wetting threads, films or thread bundles with liquids

Dry-spun synthetic fibers and filaments having an individual as-spun denier of 3 dtex are obtained by dry spinning a viscosity-stable spinning solution with a draft of at least 20.

Very fine denier synthetic fibers

The invention relates to a process for the continuous production of synthetic non-discolored filaments and fibers from a filament forming synthetic polymer being difficultly soluble in an organic polar solvent particularly polyacrylonitrile polymers which process comprises preparing a suspension of said polymer and said solvent at room temperature and subsequently heating the suspension thus formed for at least 3 minutes to at least 130.degree. C., and filtering the clear spinning solution formed without intermediate cooling, homogenizing and spinning it immediately afterwards into filaments.

Continuous process for the production of filaments or fibers from

Dry-spun synthetic fibers and filaments having an individual as-spun denier of 3 dtex are obtained by dry-spinning a viscosity-stable spinning solution with a draft of at least 20.

Process for producing very fine denier synthetic fibers

The invention relates to a process for the production of hydrophilic filaments and fibers from filament-forming synthetic polymers by spinning a solution which, in addition to a suitable solvent, contains from 5 to 50% by weight, based on the solvent and solids, of a substance which is essentially a non-solvent for the polymer, has a higher boiling point than the solvent used and is readily miscible with the spinning solvent and with a liquid suitable as a washing liquid for the filaments, and subsequently washing this substance out of the filaments, wherein a suspension is initially prepared at room temperature from the solvent, the polymer and the substance, the suspension thus prepared is subsequently heated, left for at least one minute and at most 15 minutes at a temperature of at least 30.degree. C. and of at most 60.degree. C. above the temperature at which the suspension becomes optically homogeneous, spinning the solution to form filaments or fibers and washing the said substance out of the filaments or fibers.

Growing community of inventors

Dormagen, Germany

Joachim Dross