Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F11/00—Chemical after-treatment of artificial filaments or the like during manufacture
  • D01F11/02—Chemical after-treatment of artificial filaments or the like during manufacture of cellulose, cellulose derivatives, or proteins
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
  • D01F2/06—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from viscose
  • D01F2/08—Composition of the spinning solution or the bath
  • D01F2/10—Addition to the spinning solution or spinning bath of substances which exert their effect equally well in either

Definitions

• 1,266,492 dated April 22, 1960 describes a process for the manufacture of regenerated cellulose filaments belonging to the group of polynosic fibres, having a very high tenacity, both in the conditioned state and in the wet state, a good dimenisonal stability, a high modulus of elasticity in the wet state and a low degree of swelling, the process consisting essentially in spinning a highly viscous viscose having a high gamma index and containing a cellulose of high degree of polymerisation, in a bath with a low acid content and in the presence of an aldehyde, the latter being incorporated into the spinning bath and/ or into the viscose.
• threads or yarns of even better characteristics particularly threads or yarns having high strength both in the conditioned and in the wet state
• spinning viscoses such as those described in the above mentioned French patent in weakly acid cold baths and in the presence of an aldehyde
• the essential feature of the invention being that this aldehyde is not present in the spinning bath, but on the contrary in an intermediate bath disposed between the spinning bath and the second bath serving especially for the setting after drawing.
• the present process is characterized by the use of means enabling the freshly spun filaments to be hydroextracted, on the one hand for preserving in them a highest possible gamma index and, on the other hand, for increasing their power of absorption with respect to the intermediate bath containing an aldehyde.
• the freshly spun filaments can be subjected to a compressing action by means of rollers under a pressure sufficient to obtain the desired effect without any deformation of the filaments being produced. It is even possible to cause the filaments to travel over a finely perforated roller, the interior of which is under vacuum, the said roller comprising an internal screen on the parts not covered by the filaments.
• the present invention is carried out with a viscose which contains at least 3% of cellulose and at least 1.5% of caustic soda and of which the rate of sulphidation is 35% at least, relatively to the alpha-cellulose being used.
• the gamma index of the viscose at the time of spinning must be between 45 and 100 and preferably between 55 and 90.
• the cellulose contained in the viscose must have a degree of polymerisation of at least 400 and preferably higher than 500 and be as free as possible from short chains.
• the viscosity of the viscose at the moment of spinning is at least equal to 150 poises and it is preferably higher than 400 poises.
• the viscose is spun in a first bath which contains less than 60 g./l. and preferably 8 to 40 g./l. of sulphuric acid, 10 to 120 g./l. of sodium sulphate and also small quantities (less than 1%) of zinc sulphate, but not containing any aldehyde.
• the temperature of the first bath is between 5 and 40 C., preferably between 8 and 30 C.
• the filaments After having left the first bath, the filaments are hydroextracted in one or more stages by means of roller systems or by a suction means or by any other means, and they pass in one or more stages into a cold diluted acid intermediate bath containing from 1 to 40 g./l. of an aldehyde per litre.
• This intermediate bath may moreover have the same composition as the first bath from the point of view of the content of acids and sulphates.
• the filaments then enter a second hot dilute acid bath and optionally into a third degasification bath.
• a drawing of at least 100% and preferably of at least 200% is applied to the filaments by the usual means in the first bath and/ or in the second bath and/ or during the passage through air between the first and second baths.
• the process which has just been described is adapted for the manufacture of rayon, but it is particularly suitable for the spinning of staple fibres.
• the fibres are subjected to a relaxation treatment with caustic soda, in the primary swelled state, under the conditions indicated in the first addition; they are then desulphided, degreased and dried.
• the fibres manufactured according to the process described have a high strength which reaches at least 4 g./den., when conditioned, and 3.5 g./den., when wet. They have a high modulus of elasticity, which is shown by an elongation in the wet state below 4% under a load of 0.5 g./den., and they are circular in section.
• 70% nitric acid By an appropriate treatment in 70% nitric acid, it is found that the fibres obtained have a very characteristic fibrillar structure, much closer to that of cotton than to that of other regenerated cellulose fibres. Examination with X-rays, and also the measurements of birefringence, and of accessibility (formylation), etc.
• Example A wood pulp having a content of 97.5% of alphacellulose is steeped for 30 minutes in 242 g./l. of soda at 20 and is pressed at a ratio of 3.1 with respect to the alpha-cellulose.
• the alkali-cellulose obtained is comminuted and is immediately treated with thiocarbonate, without any previous ripening, using 45% of carbon di sulphide (with respect to the cellulose).
• the xanthate formed is then dissolved in dilute caustic soda while continuing the thiocarbonation with the supplementary introduction of 10% of carbon disulphide. In this way, there is obtained a viscose with 5.75% of cellulose and 4.2% of caustic soda, having a viscosity of 600 poises, a gamma index of and containing a cellulose of DP 550.
• the viscose is then spun through a tube, using a spinneret having 8000 holes, into a spinning bath at 15 C. and containing 22 g./l. of sulphuric acid, g./l. of sodium sulphate, 1 g./l. of zinc sulphate and also small quantities of Ceponol (sodium alkyl-aryl-sulfonate).
• the filaments formed are extracted from the first bath, then hydroextracted by means of a comprising roller system, and they are conducted into an intermediate bath at 20, which contains the same quantities of acid, sodium sulphate and zinc sulphate as the first bath, and also 10 g. of formaldehyde per litre.
• the bundle of filaments then passes into a second dilute acid bath which is very hot C.) and contains a little formaldehyde entrained from the intermediate bath, and then into a degasifying bath.
• the total drawing between the first bath and the second bath is 208%, allowing for a slight detensioning in the degasifying bath.
• the roving then enters a container at a speed of 15 m./ min.
• the roving is then cut into discontinuous fibres, which are subjected to a relaxation treatment with 53 g./l. of caustic soda at 30 C.
• the fibres are then washed, desulphided, degreased and dried; they have the following characteristics:
• Fibres of 1.5 den/40 mm. obtained by the process which has just been described, were converted into yarns of the metric number 50, twist 790 t./m., and the latter were woven with a cotton warp to give a fabric of weave 35/30, weighing 118 g. per square metre.
• the fibres according to the invention are clearly superior to the fibres spun Without intermediate bath.
• the fabrics obtained with these fibres in addition to the advantages referred to, have an excellent dimensional stability, which is not affected by washing With strongly alkaline solutions.
• a process for the production of filaments of regenerated cellulose having a very high tenacity both in the conditioned state and in the wet state, good dimensional stability, a high modulus of elasticity in the Wet state which comprises spinnning a viscose which contains a cellulose whose DP is equal to at least 500, and having a viscosity of 150 poises to 1000 poises and a gamma number of 45 to 100 into a first bath containing less than 60 grams per liter of sulphuric acid, to 120 grams per liter of sodium sulphate and less than 1% zinc sulphate to produce filaments, introducing the filaments so formed into an intermediate bath containing from 1 to grams per liter of an aldehyde, introducing the filaments from said intermediate bath into a second hot regenerative bath and stretching said filaments 100% of their length at a stage prior to removal from said second bath, and fixing said stretched filaments.
• a process for the production of filaments of regenerated cellulose having a very high tenacity both in the conditioned state and in the wet state, good dimensional stability and a high modulus of elasticity in the wet state which comprises spinning a viscose which contains a cellulose Whose DP is equal to at least .500, and having a viscosity of at least 400 poises and a gamma number of to into a first bath containing from 8 to 40 grams per liter of sulphuric acid, 10 to grams per liter of sodium sulphate and less than 1% zinc sulphate to produce filaments, introducing the filaments so formed into an intermediate bath containing from 1 to 40 grams per liter formaldehyde, introducing the filaments from said intermediate bath into a second hot regenerative bath and stretching said filaments by at least 200% of their length at a stage prior to removal from said second bath, and fixing said stretched filaments.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)

Applications Claiming Priority (4)

Publications (1)

Family

ID=27445166

Family Applications (1)

Country Status (8)

Cited By (6)

Citations (6)

• 0
  • NL NL295566D patent/NL295566A/xx unknown
  • BE BE626075D patent/BE626075A/xx unknown
  • BE BE626076D patent/BE626076A/xx unknown
  • BE BE602660D patent/BE602660A/xx unknown
  • BE BE635076D patent/BE635076A/xx unknown
  • NL NL263918D patent/NL263918A/xx unknown
• 1961
  • 1961-04-15 CH CH463461A patent/CH394474A/fr unknown
  • 1961-04-17 GB GB13841/61A patent/GB910878A/en not_active Expired
  • 1961-04-19 DE DEC23920A patent/DE1234916B/de active Pending
  • 1961-04-20 SE SE4148/61A patent/SE301022B/xx unknown
  • 1961-08-23 FR FR871412A patent/FR80315E/fr not_active Expired
  • 1961-08-23 FR FR871411A patent/FR80314E/fr not_active Expired
• 1962
  • 1962-07-20 FR FR904601A patent/FR82282E/fr not_active Expired
• 1963
  • 1963-07-13 DE DE19631469060D patent/DE1469060A1/de active Pending
  • 1963-07-17 CH CH898063A patent/CH424076A/fr unknown
  • 1963-07-18 US US296117A patent/US3351696A/en not_active Expired - Lifetime
  • 1963-07-19 SE SE8049/63A patent/SE317770B/xx unknown
  • 1963-07-22 GB GB28981/63A patent/GB1002403A/en not_active Expired
• 1973
  • 1973-01-05 NL NL7300200A patent/NL7300200A/xx unknown

Patent Citations (6)

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