Abstract: The present disclosure relates to a device for melting a material without a crucible and for atomizing the melted material in order to produce powder, comprising: an atomizing nozzle; an induction coil having windings, which become narrower in the direction of the atomizing nozzle at least in some sections; and a material bar at least partially inserted into the induction coil. The induction coil is designed to melt the material of the material bar in order to produce a melt flow. The induction coil and the atomizing nozzle are arranged in such a way that the melt flow is or can be introduced into the atomizing nozzle through a first opening of the atomizing nozzle in order to atomize the melt flow by means of an atomizing gas, which can be introduced into the atomizing nozzle.

Abstract: The invention relates to a device (1) for melting a material without a crucible and for atomizing the melted material in order to produce powder, comprising: an atomizing nozzle (5); an induction coil (4) having windings (4a-d), which become narrower in the direction of the atomizing nozzle (5) at least in some sections; and a material bar (3) at least partially inserted into the induction coil (4). The induction coil (4) is designed to melt the material of the material bar (3) in order to produce a melt flow (16). The induction coil (4) and the atomizing nozzle (5) are arranged in such a way that the melt flow (16) is or can be introduced into the atomizing nozzle (5) through a first opening (20) of the atomizing nozzle (5) in order to atomize the melt flow (16) by means of an atomizing gas (19), which can be introduced into the atomizing nozzle (5).

Abstract: A spinning apparatus for producing fine threads by splicing, which comprises a plurality of protruding spinneret jets disposed in a spinneret jet portion and having spinning orifices from which the spinning dopes exit as monofils and having a plurality of acceleration jets, in particular Laval jets, whose cross section reduces, only to widen downstream of the smallest cross section, which are assigned to the spinning orifices is proposed to be provided with means for feeding gas streams which surround the monofils and are accelerated by the acceleration jets. The acceleration jet, in an at least partially plate-shaped gas jet portion, is constructed as a funnel-shaped depression into which the spinneret jet reaches to form gas flow channels.

Abstract: The invention relates to a method for producing polylactic acid, comprising the steps of obtaining lactic acid from starchy agricultural products by fermentation, ultrapurification of the lactic acid by ultrafiltration, nanofiltration and/or electrodialysis, concentration of the lactic acid and production of a prepolymer, cyclizing depolymerization to dilactide, purification of the dilactide, ring-opening polymerization of the dilactide and demonomerization of the polylactide.

Abstract: The invention relates to a method and a device for the production of essentially continuous fine threads made of meltable polymers. The polymer melt is spun from at least one spin hole (5) and the spun thread is attenuated using gas flows which are accelerated to achieve high speeds by means of a Laval nozzle (6). As a result of the specific geometry of the melt hole (4) and the position thereof in respect to the Laval nozzle (6), the temperature of the polymer melt, the throughout per spin hole and the pressures determining the velocity of the gas flow upstream and downstream from the Laval nozzle (6) are controlled in such a way that the thread reaches an internal hydrostatic pressure before solidifying, whereby said thread bursts into a plurality of fine threads.

Abstract: A spunbonded fabric of nylon 6, bonded by binders such as polyacrylates and polyurethanes, in which the filaments are substantially in the .gamma.-modification in the crystalline regions and the average molecular orientation, produced by attenuation, of the nylon 6 filaments is at most 80% of the theoretically possible orientation. It is an object of the invention to produce spunbonded fabrics of improved properties and to do so more economically, e.g. with higher outputs.

Abstract: Dimensionally stable, high-tenacity non-woven webs and process for their manufacture. The non-woven webs of the invention are distinguished by a relative grab-tensile strength of at least 200 p/g/m.sup.2, a breaking extension of not more than 50% and a shrinkage of not more than 1%, as measured at 160.degree.C, and are primarily useful as reinforceing and backing materials in the manufacture of needle-punched and tufted carpets.