Abstract: The present invention relates to ZrO.sub.2 - and SiO.sub.2 -based ceramic fibers in which the weight ratio between SiO.sub.2 and ZrO.sub.2 is comprised between 99 and 0.7. The tetragonal ZrO.sub.2 phase is stable at temperatures comprised between 0.degree. and 1500.degree. C. The process comprises the preparation of: a solution of Zr(OR.sup.1).sub.4, where R.sup.1 is an alkyl or aryl, Si(OR.sup.2).sub.4, where R.sup.2 is alkyl or aryl, an organic solvent and an acid. Vapor-phase water is bubbled in said solution, then the obtained solution is drawn and the fibers thus obtained are heated to obtain the crystallization of ZrO.sub.2 and SiO.sub.2.

Abstract: A linear block copolymer of regular structure, comprising polyamide and polyethylene glycol blocks. Two polyamide blocks (A) are bound through an intermediate polyethylene glycol block (B) according to a structural scheme (A-B-A). Fibers exhibiting a high moisture absorption strong mechanical properties and a high dyeability. Textile manufactured goods comprising said fibers. A process to obtain said block copolymer, through the preparation of a polyamide (A) and a polyethylene glycol (B), and condensation of polyamide (A) and polyethylene glycol (B) so as to obtain a (A-B-A) structure.

Abstract: A method of producing continuous multifilament yarns of polyethylene terephthalate comprising the steps of extruding the polymer in the molten state, cooling the filaments by blowing, and application of dressing, interlacing and winding. The polymer viscosity is in the range of 0.52 to 0.82. The filaments, on exiting the die, meet a conduit which protects them against air streams. Winding is carried out at rates in the range of 3,500 to 5,500 meters/minute. The fiber yielded by the method has a modulus in the 300 to 500 cN/tex range, tenacity in the range of 30 to 40 cN/tex, ultimate elongation varying from 50% to 80%, and shrinkage in water of between 3% and 8%.

Abstract: A method of high-speed spinning polyamidic fiber, comprising the steps of extruding the polymer in the molten state, cooling the filaments by blowing, and finishing, which is performed in two stages, one upstream and the other downstream of the interlacing device.The latter device includes a containing enclosure wherein the interlacing nozzle and at least two pairs of yarn thread guides are accommodated.Fibers obtained with the method have 5 to 29 knots per meter.

Abstract: A method of dyeing textile materials of polycapronamide, enabling low temperature dyeing conditions and process duration times which do not exceed the art standards, is characterized by the following combined features: (a) use of at least two discrete combinations of dyestuffs, which show different kinetic behaviors from each other; (b) maintenance of an alkaline pH at tapering values, in the extreme down to neutral; (c) use of exclusively anionic dyeing aids; and (d) maintenance through the various method steps of a maximum temperature as high as 60.degree. C., preferably as 40.degree. C.Perfectly uniform dyeing is achieved through the utilization of conventional apparata and dyeing method procedures.

Abstract: The invention is concerned with a device for replacing cops with spools in a textile yarn spinning and winding system, comprising at least one main structure moving horizontally across at least one row of spool holding spindles for holding spools. The main structure includes an assembly for cutting and reattaching the yarns to the spools which is rigidly attached to said the main structure, and at least a spool changing assembly rotatable about and movable along a vertical axis. The thread cutting and reattaching assembly is movable vertically independently of the spool changing assembly, the spool changing assembly carrying at least two horizontal rigid elongated bodies in relation to their depth, anchored cantilever-fashion, the rigid bodies having a suitable cross-section to engage with the inside diameters of the spools.

Abstract: The invention is concerned with a method of producing in-line dyed fibers, in a gel state, characterized in that it essentially consists of extruding the spinning dope in a coagulum bath, stretching the resulting filaments, scrubbing said filaments to remove residual solvent, passing the resulting filament tow through a dyeing bath at an overall rate in excess of 4 cm.sup.3 bath per second per square centimeter of tow surface area. The overall rate, being preferably in the 4 to 10 cm.sup.3 /sec per cm.sup.2 range, is achieved by means of crossflows to the forward advance direction of said tow, and alternately directed to and from said tow, the tow residence time in the dyeing bath being no longer than 5 seconds. The tow is then subjected to a dye fixing heat treatment, and is then scrubbed, finished, and dried. The method is particularly suitable for use with substantially acrylic and modacrylic fibers.

Abstract: The invention is concerned with a combination of molecular weight controllers to be used in the production of a stabilized polyamide having a low content of monomers and oligomers and a high dye-taking capability by polymerization of caprolactam. The combination comprises: (a) a primary monofunctional amine having its boiling point at 180.degree. C. above, and a basic dissociation constant K.sub.b .gtoreq.1.7.times.10.sup.-5 ; (b) a monofunctional organic acid having a K.sub.a >1.5.times.10.sup.-5 ; and (c) an aminoacid containing at least ten carbon atoms having the --NH.sub.2 group salified by a monofunctional organic or inorganic acid which has K.sub.a >1.0.times.10.sup.-2. With this combination, a polyamide is obtained which, following residence in the molten state, has a monomer content of 0.25% or less and a dimer content of 0.15% or less.