| 摘要 |
522,542. Artificial silk. COMPTOIR DES TEXTILES ARTIFICIELS. Dec. 14, 1938, No. 36495. Convention date, Dec. 21, 1937. [Class 2 (ii)] Crimped artificial textile filaments are manufactured from viscose, cuprammonium cellulose solutions and other aqueous solutions of cellulosic derivatives which yield regeneratable soluble compounds upon coagulation, by spinning the solution, under such conditions that the velocity of the solution emerging from the jet is a multiple of the draw-off velocity, into a spinning bath having a rapid coagulating action but only a slow or delayed regenerating action so that the filaments are substantially coagulated throughout before any regeneration is initiated. Suitable spinning baths are those rich in alkaline salts, ammoniacal salts such as ammonium sulphate, or concentrated lower fatty acids such as acetic or formic acid. The spinning bath may also contain small proportions of mineral acids such as sulphuric acid. The coagulated filaments may be regenerated in baths more acid than the spinning baths ; for example, regeneration may take place in a sulphuric acid bath which may contain salts or glucose. Regeneration may also be effected with acid gases or hot saline baths. The filaments may then be subjected to drawing in the moist state, followed by drying without tension. In examples, viscose is spun into a bath containing sulphuric acid and sodium or ammonium sulphate or containing acetic acid and the coagulated filaments are regenerated in a bath containing sulphuric acid, sodium sulphate and glucose. The spinning solution may contain pigments, liquid delustering agents, substances adapted to evolve gases or substances such as proteins which impart to the filaments produced an affinity for acid colouring matters. The Specification as open to inspection under Sect. 91 states that the process of the invention is applicable to all aqueous solutions of cellulose derivatives, including solutions of feebly substituted cellulose esters or ethers. In an example, a methyl cellulose of a low degree of etherification is dissolved in sodium hydroxide solution and the mixture spun into a bath containing ammonium sulphate, ammonium hydroxide and glucose. The filaments formed are then immersed in a bath containing sulphuric acid, sodium sulphate and glucose. This subject-matter does not appear in the Specification as accepted. |
