US3539679A - Process for producing polynosic fibers - Google Patents

Process for producing polynosic fibers Download PDF

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Publication number
US3539679A
US3539679A US569685A US3539679DA US3539679A US 3539679 A US3539679 A US 3539679A US 569685 A US569685 A US 569685A US 3539679D A US3539679D A US 3539679DA US 3539679 A US3539679 A US 3539679A
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Prior art keywords
bath
filaments
sulfuric acid
fibers
viscose
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US569685A
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English (en)
Inventor
Yukio Kimura
Taro Yamamura
Atsushi Kawai
Masamichi Ikeda
Takehiro Katsuyama
Takanori Oda
Sakae Kondo
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Mitsubishi Rayon Co Ltd
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Mitsubishi Rayon Co Ltd
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    • 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

  • the present invention relates to process for producing polynosic fibers having high tenacity, high knot tenacity, high loop tenacity, high wet modulus, high fibrillation resistance and excellent dyeability.
  • High Wet Modulus Fiber which are generally distinguished from polynosic fiber.
  • the characteristic features of High Wet Modulus Fiber resides in that they have suitably high elongation and excellent lateral properties of the fiber such as loop tenacity and that they are not brittle and have little tendency to fibrillation, and therefore it is ditferent from polynosic fiber in these points.
  • polynosic fiber As regards polynosic fiber, a number of improved methods have been thereafter proposed, and as a result, polynosic fibers of fairly good properties are presently being marketed. However, the polynosic fibers are still found unsatisfactory insofar as the lateral properties of the fiber such as loop tenacity and fibrillation resistance are concerned.
  • An object of the present invention is to provide fibers having high knot tenacity, high loop tenacity, high fibrillation resistance and excellent dyeability without spoiling the characteristic features of polynosic fiber, and a process for producing such fibers. More particularly the object of the present invention is to provide polynosic fibers having wet tenacity of 3.4 to 5.0 g./d., wet modulus of 1.0 to 2.0 g./d. at 5% elongation, loop tenacity of 2.0 to 4.0 g./d., fibrillation degree of below 20, and solubility of less than 70% in 2 N sodium hydroxide solution at 20 C. after ethanolysis. Still further object of the present invention is to provide a process for producing these polynosic fibers.
  • the above-mentioned objects of the present invention can be achieved by extruding a viscose having 'y-value of more than 55 into a coagulation bath containing from 8 to 25 g./l. of sulfuric acid, from 0.05 to 1.5 g./l. of zinc sulfate and from 10 to 150 g./l.
  • the sum of the concentrations of the zinc sulfate and the sodium sulfate being from 0.5 to 60 g./l.
  • brittleness and fibrillation properties of polynosic fiber are attributed to high molecular orientation, high crystallinity and high fibrillar structure which are formed through slow coagulation and regeneration of the viscose extruded into a coagulation bath and subsequent high stretch of the filament.
  • the filaments withdrawn from the coagulation bath are introduced into the second bath containing limited concentration of zinc sulfate, sodium sulfate and very low concentration of sulfuric acid, so that the outer layer of the filaments are subjected to swelling treatment with alkali contained in the interior of said filaments to relieve their excessively orientated structure, thereby producing filaments having excellent properties, for example, high fibrillation resistance and non-brittleness without spoiling the characteristic features of polynosic fiber.
  • the fibers in accordance with the present invention are excellent not only in mechanical property and fibrillation resistance but also in alkali resistance and dyeability. These are great characteristic features of the present invention.
  • either high grade or common pulp can be used.
  • Ageing of alkali cellulose is carried out according to a desired polymerization degree of cellulose.
  • the polymerization degree of cellulose in viscose is preferably above 350, more preferably from 400 to 650.
  • preferable viscosity of viscose on spinning is from to 1000 poises at 20 C., more preferably from 200 to 600 poises.
  • concentration of cellulose in viscose is determined in accordance with the polymerization degree of the cellulose, and it is usually from 4 to 8%.
  • the alkali concentration in viscose is preferably from 2 to When the alkali concentration is above 5%, the desirable concentration of sulfuric acid in the coagulation bath becomes higher, thereby reducing swelling of the filaments in the second bath.
  • the 'y-value of viscose on spinning must be above 55. When the 'y-value is below 55, that of the filaments introduced into the second bath becomes too W, that is, an amount of cellulose xanthate in the filaments decreases, and on this count swelling of the filaments becomes insufficient, and the 'y-value of viscose is preferably above 65.
  • surface active agent soluble in viscose and insoluble in coagulation bath may be added to viscose.
  • surface active agents those having the following general formulas are preferably employed:
  • R is an alkyl group having more than 8 carbon atoms
  • M is hydrogen, alkali metal or organic base
  • m is an integer of 1 or 2
  • n is an integer not greater than 2
  • X is an alkylene group having from 1 to 3 carbon atoms, at least one member of the group consisting of Y, Y and Y" is a (CH ),,COOM group and the remainder is hydrogen atoms.
  • R and R are alkyl groups having more than 7 carbon atoms, acyl groups or hydrogen atoms, but there is no case where R and R are simultaneously hydrogen atoms.
  • M is hydrogen or alkali metal
  • In is 0 or a positive integer and n is an integer not greater than 2, and
  • RCONX (CH CO OM wherein R is a saturated or unsaturated hydrocarbon radical having from 7 to 17 carbon atoms, X is a hydrogen or lower alkyl group, M is a hydrogen or alkali metal and n is an integer of 1 or 2.
  • the amount of surface active agent to be added is from 0.05 to 0.3% based on the weight of viscose.
  • the concentration of the sulfuric acid in the coagulation bath must be from 8 to 25 g./l.
  • concentration of sulfuric acid is below 8 g./l.
  • the spinning becomes difiicult
  • concentration of sulfuric acid is above 25 g./l.
  • concentration of acid adhered to the filaments withdrawn from the coagulation bath becomes excessively high and on this account swelling of the filaments in the second bath becomes insufiicient.
  • the concentration of zinc sulfate in the coagulation bath is one of the most important factors of the present invention. Said concentration must be from 0.05 to 1.5 g./l.
  • the action of the zinc sulfate is to form a thin film of zinc xanthate on the surfaces of the filaments formed in the coagulation bath and the resultant thin film is to control the diffusion of acid into the interior of the filaments, thereby promoting the swelling of the filaments in the second bath with alkali present in the interior of said filaments.
  • concentration of zinc sulfate is below 0.05 g./l.
  • the formation of zinc Xanthate film is insufficient and thereby the effect of the second bath cannot be exhibited.
  • said concentration is above 1.5 g./ 1., the Youngs modulus of the fibers to be obtained decreases.
  • Suitable concentration of sodium sulfate is from 10 to 150 g./l. and the concentration below 10 g./l. is economically undesirable. On the contrary, when said concentration is above 150 g./l., the fiber properties become inferior.
  • Optimum temperature of coagulation bath is below 35 C., preferably below 25 C.
  • the temperature is elevated above 35 C., the value of filaments in coagulation bath excessively falls.
  • the immersion length of the coagulation bath is determined in connection with composition and temperature of the coagulation bath, spinning speed and the like, hence it cannot be indiscriminately defined. But it is preferred to be as short as possible.
  • the filaments formed in a coagulation bath are withdrawn from the coagulation bath in such a state where the 'y-value of said filaments is above 40, and then they are introduced into the second bath containing sulfuric acid, zinc sulfate and sodium sulfate in a state where said filaments have a 'y-value of above 30.
  • the concentration of the sulfuric acid in the second bath must be below 3 g./l., that of the zinc sulfate must be from 0.005 to 3 g./l. and the sum of the concentrations of the zinc sulfate and the sodium sulfate must be from 0.5 to 60 g./l.
  • the concentration of sulfuric acid in the second bath is very low, swelling of the filaments becomes excessively large in case salts are not present in the second bath, and thereby the properties of the fibers obtained become inferior.
  • an excessively high concentration of salts is not desirable because the swelling effect of alkali is restrained.
  • especially the effect of the zinc sulfate in the second bath is remarkable. This is considered to be attributable to that besides a proper swelling restraining action, zinc sulfate controls the decomposition of the zinc xanthate on the surface of the filaments formed in the coagulation bath to make swelling of the filaments effective.
  • Temperature of the second bath is normally above 50 C., preferably above C. particularly when formaldehyde is contained in the coagulation bath.
  • the filaments withdrawn from the coagulation bath are introduced in a state where its v-value is above 40 into the second bath in which the concentration of sulfuric acid is below 3 g./l., that of zinc sulfate is from 0.05 to 3 g./l. and the sum of the concentrations of the zinc sulfate and the sodium sulfate is from 0.5 to 50 -g./l. and stretched in said bath.
  • the filaments withdrawn from the coagulation bath may be immediately treated with a diluted aqueous solution of heavy metal salt and then introduced into the second bath.
  • heavy metal salt cadanium sulfate and nickel sulfate are preferable.
  • concentration of heavy metal salt is preferably from 0.2 to 1 g./l.
  • Temperature of an aqueous solution of heavy metal salt is preferably below room temperature.
  • the filaments withdrawn from the second bath, if necessary after cutting, are introduced into the third bath (regeneration bath).
  • the filaments are completely regenerated.
  • an aqueous bath containing from 2 to 15 g./l. of sulfuric acid and kept at a temperature above 80 C. is preferably employed.
  • polynosic fibers having from 3.4 to 5.0 g./d. of wet tenacity, from 1.0 to 2.0 g./d. of wet modulus at 5% elongation, from 2.0 to 4.0 g./d. of loop tenacity fibrillation degree of below 20 and solubility of lower than 70% in 2 N sodium hydroxide solution at 20 C. after ethanolysis.
  • FIGS. 1-3 show the relation between concentration of sulfuric acid in the second bath and fiber property.
  • FIGS. 4-6 show the state of fibrillation of fibers.
  • the present invention is illustrated by referring to the following examples, but the scope of the present inven- 6
  • FIGS. 46 are photographs showing states of fibrillation of fibers obtained by the procedure for measuring the fibrillation degree. From these photographs, it is seen that the fibers produced according to the present invention are less prone to fibrillation.
  • Example l rvas extn id d into a coagu ation at containing 4 g. o sul uric EXAMPLE 1 acid, 75 g./l. of sodium sulfate and 0.3 g./l. of zinc sul- Alkali cellulose was prepared from wood pulp ac- 1O fate and kept at 20 C., through a spinneret having 12,000 cording to usual method. After aging, the resultant alkali orifices of 0.06 mm. diameter.
  • cellulose was xanthated with 57% of carbon disulfide
  • the filaments withdrawn from the coagulation bath based on the weight of cellulose.
  • the Xanthate was disof which the immersion length was 30 cm., were immesolved in dilute aqueous sodium hydroxide solution to diately introduced into the second bath containing 1.5 obtain viscose containing 6.5% of cellulose, the polymg./l. of sulfuric acid, 7 g./l. of sodium sulfate and 0.3 erization degree of the cellulose was 480, and 3.9% of g./l. of zinc sulfate and kept at 90 C., and stretched to total alkali. The viscose was then filtered, deaerated and 240%.
  • the 'y-value of the filaments introduced into the ripened to obtain a viscosity of 320 poises at C. second bath was 53.
  • the spinning speed was 15 m./min. and 'y-value of 81.
  • Through a spinneret having 12,000 20 The stretched filaments were withdrawn from the second orifices of 0.06 mm. diameter, the resultant viscose was bath and then passed through a bath having the same extruded into a coagulation bath containing 15 g/l. of composition and temperature as in the second bath withsulfuric acid, 60 g./l. of sodium sulfate and 0.6 g./l. of out stretching, and thereafter, passed through the third zinc sulfate and kept at 20 C.
  • the properties of the fibers thus was cm., were immediately introduced into the second obtained (A) are shown in the following table, compared bath containing 1 g./1. of sulfuric acid, 15 g./l. of sodium with those of the fibers (B) obtained in the same manner sulfate and 0.4 g./l. of zinc sulfate and kept at 90 C., as in this example except that zinc sulfate was not conand then stretched to 250%.
  • the xanthate was dis-
  • the properties of the fib r (A) thus obtained were solved in aqueous sodium hydroxide solution to obtain vis- Shown in the f ll i table, compared with those f cose containing 5.5% of cellulose, the polymerization depolynosic fibers being marketed and those of fi be 's gree Of the cellulose Was and Of total alkali. represented i (c), as a comparative example, b i d This viscose was filtered, deaerated and ripened to obtain in th Same manner as i thi example except th t th a viscosity of 390 poises and 'y-value of 88.
  • the viscose concentration of the sulfuric acid in the second bath was extruded through a spinneret having 18,000 r fi 10 g./l. of 0.06 mm. diameter, into a coagulation bath containing Wet tenacity alter Solubility in Dry treated 2 N NaOH Dry Wet Dry Wet knot Loop Wet modwith 5% solution tenaetenacelongaelongatenactenaculus at NaOH Water Dye ab- (20 C.) after ity, ity, tion, tion, 'y, ity, 5% elongasolution, swelling, sorption, Fibrillation ethanolysis, Denier g./d. g./d. percent percent g./d. g./d.
  • the filaments by cutting fiber in 5 mm. length and then crushing the 65 withdrawn from the coagulation bath, of which the immercut fiber with a domestic mixer (320W, 3,000 r.-p.m.) for sion length was 35 cm, were immediately introduced into 15 minutes together with water 10,000 times the amount the second bath containing 0.8 g./l. of sulfuric acid, 10 of the fibers at 20 C. g./l. of sodium sulfate and 0.5 g./l. of zinc sulfate and Ethanolysis conditions: 1 g. of sample fiber is sub kept at 90 C., and then stretched to 225%. The y-value jected to depolymerization in 100 cc.
  • FIGS. l-3 show the relation of the properties of the the third bath containing 5 g./l. of sulfuric acid and fiber obtained by the same method as in this example kept at C. to complete regeneration. except that the concentration of sulfuric acid in the s'ec- 75
  • the properties of the fibers thus obtained (A) are 0nd bath is varied within a range of less than 10 g./l.
  • Denier g./d. percent g./d. g./d. g./d. percent tion degree percent EXAMPLE'4 15 complete regeneration and then subjected to after-treat- Alkali cellulose was prepared from wood pulp according to usual method. After ageing, the resultant alkali cellulose was xanthated with 60% of carbon disulfide based on the weight of cellulose.
  • N,N'-dioctyltriethylenetetramine monoacetate (Na salt) based on the weight of the viscose was added together with aqueous sodium hydroxide solution and water to obtain a viscose containing 6.5% of cellulose, the polymerization degree of the cellulose 'was 490 and 4.1% of total alkali.
  • This viscose was filtered, deaerated and ripened to obtain a viscosity of 310 poises and 'y-value of 87.
  • the viscose was extruded through a spinneret having 12,000 orifices of 0.06 mm. diameter, into a coagulation bath containing 13 g./l.
  • the filaments withdrawn from the coagulation bath were immediately introduced into the second bath containing 0.1 g./l. of sulfuric acid, 2.0 g./l. of sodium sulfate and 0.2 g./l. of Zinc sulfate and kept at 90 C., and stretched to 255%.
  • the 'y-value of the filaments introduced into the second bath was 59.
  • the spinning speed was 23 m./minute.
  • the filaments withdrawn from the second bath were introduced into the third bath containing 3 g./l. of sulfuric acid and kept at 80 C. to complete regeneration and then subjected to after-treatment according to usual method.
  • the viscosity of the viscose was 280 poises, the 'y-value was 86, and the polymerization degree of the cellulose was 520 on spinning.
  • the viscose was extruded into a coagulation bath containing 13 g./l. of sulfuric acid, 70 g./l. of sodium sulfate and 0.5 g./l. of zinc sulfate and kept at 20 C., and the resultant filaments were withdrawn from the coagulation bath, immediately introduced into the second bath containing 0.3 g./l. of sulfuric Inent according to usual method.
  • a process for producing polynosic fibers characterized by extruding a viscous having 'y-value of above 55 into a coagulation bath substantially free of formaldehyde containing from 8 to 25 g./l. of sulfuric acid, from 0.05 to 1.5 g./l. of zinc sulfate and from 10 to g./l.
  • the sum of the concentrations of the Zinc sulfate and the sodium sulfate being from 0.5 to 50 g./l. in a state where 'y-value of the filaments is above 30, stretching the filaments more than 150% while immersed in said second bath, withdrawing the stretched filaments and then introducing the filaments into a third bath to complete regeneration.

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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)
US569685A 1965-08-03 1966-08-02 Process for producing polynosic fibers Expired - Lifetime US3539679A (en)

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JP4704065 1965-08-03
JP5135965 1965-08-23
JP6786365 1965-11-05

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3870596A (en) * 1971-06-22 1975-03-11 Tachikawa Res Inst Process for the preparation of dispersion water for incompletely regenerated cellulose substance
US3875141A (en) * 1968-02-16 1975-04-01 Chimiotex Regenerated cellulose filaments
US20100190891A1 (en) * 2007-05-09 2010-07-29 Borealis Technology Oy Polyefin compositions with highly crystalline cellulose regenrate fibers
WO2013020150A1 (de) 2011-08-10 2013-02-14 Lenzing Ag Aktivkohle-enthaltende cellulosische man-made faser sowie verfahren zu deren herstellung und verwendung

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2293504A1 (fr) * 1974-12-04 1976-07-02 Rhone Poulenc Textile Procede pour l'obtention de fibres de cellulose regeneree ayant un pouvoir de fibrillation elevee
IT1129652B (it) * 1980-01-09 1986-06-11 Snia Viscosa Procedimento perfezionato per la filatura in continuo di rayon viscosa

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2860480A (en) * 1956-04-18 1958-11-18 Du Pont Regenerated cellulose structures and process for producing them
US3038778A (en) * 1957-06-21 1962-06-12 American Enka Corp Manufacture of viscose rayon
US3084021A (en) * 1960-02-29 1963-04-02 Morimoto Saichi Process for producing regenerated cellulose filaments
US3139467A (en) * 1962-11-14 1964-06-30 Chimiotex Method for spinning viscose
US3226461A (en) * 1962-02-27 1965-12-28 Courtaulds North America Inc Manufacture of regenerated cellulose fibers from viscose
US3320117A (en) * 1962-05-31 1967-05-16 Tachikawa Res Inst Process for the manufacture of rayon paper or non-woven fabric by the wet system
US3324216A (en) * 1962-05-16 1967-06-06 Toyo Spinning Co Ltd Viscose spinning process
US3341645A (en) * 1963-03-07 1967-09-12 Teijin Ltd Method of producing viscose rayon staple and a spinning apparatus for use in the method
US3351696A (en) * 1960-04-22 1967-11-07 Cta Cie Ind De Textiles Artifi Method for producing regenerated cellulose products
US3352957A (en) * 1962-11-06 1967-11-14 Chimiotex Process for spinning cellulosic fibers
US3381075A (en) * 1962-05-28 1968-04-30 Teijin Ltd Process for preparation of viscose regenerated cellulose fibers
US3388117A (en) * 1963-03-28 1968-06-11 Courtaulds North America Inc Filaments of regenerated cellulose
US3419652A (en) * 1963-09-10 1968-12-31 Mitsubishi Rayon Co Process for producing highly crimped fibers

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2860480A (en) * 1956-04-18 1958-11-18 Du Pont Regenerated cellulose structures and process for producing them
US3038778A (en) * 1957-06-21 1962-06-12 American Enka Corp Manufacture of viscose rayon
US3084021A (en) * 1960-02-29 1963-04-02 Morimoto Saichi Process for producing regenerated cellulose filaments
US3351696A (en) * 1960-04-22 1967-11-07 Cta Cie Ind De Textiles Artifi Method for producing regenerated cellulose products
US3226461A (en) * 1962-02-27 1965-12-28 Courtaulds North America Inc Manufacture of regenerated cellulose fibers from viscose
US3324216A (en) * 1962-05-16 1967-06-06 Toyo Spinning Co Ltd Viscose spinning process
US3381075A (en) * 1962-05-28 1968-04-30 Teijin Ltd Process for preparation of viscose regenerated cellulose fibers
US3320117A (en) * 1962-05-31 1967-05-16 Tachikawa Res Inst Process for the manufacture of rayon paper or non-woven fabric by the wet system
US3352957A (en) * 1962-11-06 1967-11-14 Chimiotex Process for spinning cellulosic fibers
US3139467A (en) * 1962-11-14 1964-06-30 Chimiotex Method for spinning viscose
US3341645A (en) * 1963-03-07 1967-09-12 Teijin Ltd Method of producing viscose rayon staple and a spinning apparatus for use in the method
US3388117A (en) * 1963-03-28 1968-06-11 Courtaulds North America Inc Filaments of regenerated cellulose
US3419652A (en) * 1963-09-10 1968-12-31 Mitsubishi Rayon Co Process for producing highly crimped fibers

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3875141A (en) * 1968-02-16 1975-04-01 Chimiotex Regenerated cellulose filaments
US3870596A (en) * 1971-06-22 1975-03-11 Tachikawa Res Inst Process for the preparation of dispersion water for incompletely regenerated cellulose substance
US20100190891A1 (en) * 2007-05-09 2010-07-29 Borealis Technology Oy Polyefin compositions with highly crystalline cellulose regenrate fibers
WO2013020150A1 (de) 2011-08-10 2013-02-14 Lenzing Ag Aktivkohle-enthaltende cellulosische man-made faser sowie verfahren zu deren herstellung und verwendung

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DE1669494B2 (de) 1975-07-03
CH475377A (fr) 1969-07-15
DE1669494A1 (de) 1970-12-03
NL134509C (es)
GB1096509A (en) 1967-12-29
NL6610893A (es) 1967-02-06

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