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
  • D01F2/24—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives
  • D01F2/28—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives from organic cellulose esters or ethers, e.g. cellulose acetate

Definitions

• the present invention relates to the wet spinning of organic acid esters of cellulose containing fewer than about 0.29 free hydroxyl group per anhydroglucose unit of the cellulose molecule, particularly cellulose triacetate.
• the cellulose triester is cellulose triacetate having an acetyl value of at least about 60% and generally above 61% calculated as combined acetic acid and is employed as a solution of about 18 to 26% concentration by weight in a solvent comprising a halogenated lower alkane which may contain up to about 15% by weight of a lower alkanol, e.g. methylene chloride plus methanol.
• the spin bath is preferably also made up of the halogenated al-kane and alkanol, except that the alkauol proportion is sufficiently high to ef fect precipitation of the cellulose triacetate.
• the halogenated alkane concentration may range from about 25 to 65% by weight of the spin bath, its concentration desirably varying inversely with the temperature of the spin bath which may range from about room temperature up to about the boil, e.g. about 15 to 45 C.
• the resulting products exhibit excellent physical properties and can readily be distinguished from other filamentary materials such as dry spun cellulose triacetate, for example.
• the individual filaments are generally substantially circular in cross-section, in contrast to the bulbous or potato-shaped cross-section of dry-spun filaments. Also, stress-strain curves for the wet-spun cellulose triacetate filaments show a higher modulus of elasticity and higher resistance to deformation throughout the whole range of strain, as compared with dry-spun cellulose triacetate filaments.
• the filaments produced in accordance with the Riley .u'isclosure exhibit tenacities in excess of about 1.8 and usually 2 grams per denier at elongations of at least about 18 and usually 20%, even for filaments whose denier is in the range of 1.5 to 4.
• the energy of rupture i.e. the area under the stress-strain curve from zero stretch to break, is high, above 800 dyne cm. for 1 cm. of a 3 denier filament.
• These filamentary materials are characterized by radial uniformity. This can be determined by treating the filamentary materials with a saponifying agent which deesterifies the surface portions of the filamentary material, forming a cellulose skin which is then removed with a solvent for cellulose. When subjected to this treatment a filamentary material which is non-uniform exhibits different properties as compared with the original material, while a radially uniform material has the same properties as before.
• the surface removal can be effected, for example, by wetting the filaments to be tested in cold water containing 0.1 gram per liter of Triton X-100 (iso-octyl phenyll ether or polyethylene glycol) then immersing them in 1000 times their weight of a 50 grams per liter solution of sodium hydroxide at C. for from 30 seconds to 3 minutes, and quickly transferring them to cold running water for 5 minutes.
• the filaments are then soured in acetic acid for 15 minutes, and again rinsed in running water for 15 minutes.
• the filaments After drying in air, the filaments are immersed at room temperature for 3 minutes in a solution made up of equal weights of cupriethylene diamineand water to dissolve the cellulose skin formed by the saponification. The filaments are then rinsed, soured, rinsed and dried as before.
• the dyebath was water containing 50 grams per liter of dispersed Amacel Red 2B (a red cellulose acetate dye), 1 gram per liter of Igepon T-5 l (a dispersing agent) and 1 gram per liter of sodium hexametaphosphate; the bath was maintained at 95 C.
• Amacel Red 2B a red cellulose acetate dye
• Igepon T-5 l a dispersing agent
• the Riley filamentary materials show a relatively high overall birefringence after complete saponification of said materials.
• the overall birefringence of the saponified material is above about 0.031, typical values being in the range of about 0.034 to 0.037.
• This overall birefringence is the sum of the birefringence through the fiber and is measured, in conventional manner, by a transmission technique.
• the filamentary material is saponified completely by immersion for atleast 30 minutes in times its weight of a solution containing, by weight,
• Cellulose triacetate filamentary materials produced in accordance with the Riley disclosure exhibit definite rubbery properties at elevated temperatures. This is demonstrated in the following manner: A 125 denier 40 filament yarn is held at constant length (e.g. 10 inches) and heated to a temperature of 220 C. at a just perceptible initial tension (about 0.03 g.). The temperature is then cycled between 217 C. and 223 C. It will be found that the tension on the filament increases as the temperature increases and decreases very perceptibly as the temperature decreases, typical of a rubber. By way of comparison, if the temperature'of the filament is cycled between 162 C. and 168 C., the. tnesion will be found to decrease as the temperature increases, typical of a glass.
• the Riley cellulose triacetate filamentary material may be heat treated to raise the safe ironing temperature of fabrics produced therefrom and to improve the dimensional stability, resistance to creasing, permanence of pleating, and the like.
• the wet-spun filamentary mate rial shows substantially no shrinkage or decrease of tenacity on such heat treatment. In fact, the tenacity may even increase. For example, a filament having an original tenacity of 2.15 grams per denier, when heat treated in air at 210 C. for 5 minutes shrinks less than 1% and has a final tenacity of 2.37 g./den.
• Cellulose triacetate filamentary material produced in accordance with the Riley invention is also characterized by resistance to creep at elevated temperature. This is demonstrated as follows: One end of a filament is anchored within a horizontal heating tube. 10 inches from the anchored end, the filament is knotted to a glass filament which extends outside the tube and runs over a pulley. A weight is suspended from the protruding end of the glass filament. With various size weights suspended from the glass filament the tube is heated and the displacement of the weight with change in temperature is noted. Cellulose triacetate filaments produced by dry spinning the initial solutions begin to creep at about 168 C. The wet-spun filamentary materials do not creep comparably below about 178183 C. The rate and amount of creep for dryspunrfilaments under a load of 0.033 gram per denier are only reached for the wet-spun filamentary material at a load equal to or in excess of 0.067 gram per denier.
• the crimps in adjacent filaments of the bundle or tow are randomly arranged, out of alignment; the crimp being threedimensional, either helically or randomly threedimensional, and not substantially in a single plane.
• the tow is much more voluminous or lofty than the conventional tows.
• Typical crirnped filaments contain 8 or more, e.g. 8 to 12, fine crimps per inch, the amplitude of the crimp being irregular but generally being onthe order of 1 mm. and the percent crimp, based on the straightened length, being above about 4%.
• Percent crimp is defined as Straightened lengthcrimped length Straightenecl length While this procedure overcomes the tendency to coalesce, it has been :found that if the resulting tow is in tended to be formed into a staple fiber yarn by the steps of completing drying, lubricating, cutting into staple fibers, carding to produce a sliver and spinning it is sometimes necessary to repeat the carding step to produce a sliver which will yield a satisfactory yarn upon spinnmg.
• Another object is to provide a process for producing cellulose triester filamentary material which can easily be handled in staple fiber form and can be converted into yarn in conventional manner.
• the cellulose triester dope is extruded into a spin bath exerting a swelling action thereon in the presence of a member selected from the group consisting of hydrocarbon oils, silicone oils, and poly-lower alkylene glycols.
• Representative materials include poly-dimethyl-siloxane, polyethylene glycol and the copolymer of ethylene and propylene oxides having molecular weights ranging from about 600 to 6000. From the standpoints of cost, tensile properties and physical condition of the product the best results are obtained using a hydrocarbon oil which is incorporated in the spin bath.
• the hydrocarbon oil is a white mineral oil having an essentially aliphatic base, such as parafiinic or naphthenic base, and having a viscosity of about 30 to 400 seconds as measured at 38 C. (100 F.) in the Saybolt Universal viscosimeter, and preferably a viscosity of about 40 to 100 seconds.
• Its molecular weight desirably ranges from abouf to 400 and preferably about 200 to 300.
• Its initial boiling point generally is in excess of about 200 C. and preferably in excess of about 250 C. and its vapor pressure is generally less than about 0.1 mm. Hg at 38 C.
• the hydrocarbon oil is generally present in about 0.1 to 3% and preferably about 0.5 to 1% to exert its beneficial effect to a substantial degree. Lower proportions result in a lesser improvement while higher proportions are less economical and do not appreciably improve the results achieved. If the mineral oil is added as a dispersion or solution along with other materials, e.g. pigments, anti-static agents or the like, the dispersion or solution is obviously added in amount sufficient to provide the desired percentage of the hydrocarbon oil component.
• the exact proportion of hydrocarbon oil in the spin bath will vary with factors such as the feed ratio of spin bath to filamentary material, the denier and residence time of the filamentary material in the spin bath, the degree of extraction of spent spin bath from the filaments as they leave the spin bath, and the like. All factors considered, the concentration of hydrocarbon oil should generally be sufficient to leave about 0.1 to 5% and preferably about 0.5 to 2% of hydrocarbon oil on the filaments based on the dry weight of the filaments.
• the filaments can be dried in any desired manner and an anti-static agent may be applied if desired and if not previously applied either in the dope, the spin bath or to the wet filaments.
• the hydrocarbon oil surprisingly improves the spinning stability, i.e. at a given spinning speed there are fewer broken fils or for a given number of fil breaks the maximum permissible spinning speed is higher with hydrocarbon oil in the spin bath. While not wishing to be bound thereby it is believed that the hydrocarbon oil retards the rate of coagulation of the filaments. At any rate, the filaments exhibit higher tenacities and/ or elongation than when no hydrocarbon oil is in the spin bath, the tensile factor, i.e. tenacity /elongation often being or more greater than without the hydrocarbon oil.
• the loop tensile properties are also improved by the pres ence of the hydrocarbon oil, the product exhibiting increased resistance to abrasion and fiexural fatigue.
• the hydrocarbon oil is distributed substantially uniformly on the surface of the filaments, as contrasted with the discontinuous film produced by spraying or brushing hydrocarbon oil onto dry filaments.
• 'I he filaments exhibit little or no coalescence even in the absence of spe cial drying or aftertreatmen-ts.
• the staple fibers can be processed on conventional equipment with no special techniques.
• the spinning stability, physical properties, freedom from coalescence and physical properties for filaments extruded into spin baths containing mineral oil are superior to those for filaments which have been treated with mineral oil subsequent to leaving the spin bath.
• Example I A 22% solution in 9% methylene chloride/methanol of cellulose triacetate, having an acetyl value of 61.5% calculated as combined acetic acid, is extruded horizontally through an orifice having a diameter of 0.1 mm. into a 1 meter long bath of 41.5/58.5 methylene chloride/methanol at 35 C. and containing 0.5% by weight of the total bath of a white mineral oil having a viscosity at 100 F. of 50 Saybolt Universal seconds. The monofi-lament is taken up at a speed of 72 meters per minute and is 3 denier.
• Its tenacity is 2.09 grams ,per denier and its elongation is 26.2%, each of these values being several percent higher than the corresponding values for a monofilament produced identically except for the absence of mineral oil from the spin bath.
• the loop tenacity is increased by about 25% and the loop elongation by about 50% when mineral oil is in the spin bath, the loop tensile properties being obtained by bending two fibers into U-shape, hooking one through the other and pulling at each pair of free ends.
• Example II The same dope as in Example I is extruded horizontally through a spinnerette having 40 orifices 0.1 mm. in diameter into a 42/58 methylene chloride/methanol spin bath at 35 C. and containing 0.12% by weight of the white mineral oil of Example I. 3 inches from the spinnerette the freshly formed filaments enter the flared en- 6 trance of a horizontal glass tube 26 inches long and 10 mm. in internal diameter through which the spin bath flows, concurrently with the coagulating filament bundle, at a linear velocity of 26 meters per minute. From the exit end of the spinning tube the yarn bundle is passed about three guides which separate it from the spin bath.
• the yarn then passes three times through a 2 inch internal diameter copper tube 53 inches long, between feed rolls operating at a peripheral speed of 150 meters per minute and then to a downtwister take up bobbin. Air at C. is blown through the copper tube to effect drying.
• the yarn is free of coalescence, has a soft hand and excellent physical properties; in the absence of mineral oil in the spin bath the filaments are coalesced to an appreciable degree and the yarn has a harsh or boardy hand.
• Example III The process of Example II is repeated except'that the 0.12% of mineral oil is replaced by 1% by weight of the spin bath of polyethylene glycol (polyethylene oxide) having a molecular weight of about 1500. The product is free of coalescence.
• polyethylene glycol polyethylene oxide
• Example IV The dope of Example -I is extruded upwardly through a spinnerette having 1396 holes 0.1 mm. in diameter into 41.7/58.3 methylene chloride/methanol at 34.7 C. and containing 2.3% based on total spin bath weight of the oil of Example I. From the spinnerette the freshly formed filaments travel 49 inches through a spinning column having an internal diameter of 1 inch. Fresh spin bath is supplied below the spinnerette at the rate of gallons per hour, moves in the same direction as the filaments and overflows at the top of the column. Spent spin bath is wiped away, the filaments pass between driven rolls operating at a peripheral speed of v80 meters per minute, they are separated from one another by passage through an air jet as described in application Serial No.
• the driven roll speed of 80 meters per minute is several times the speed at which dope passes through the spinnerette, causing stretching or drawdown of the filaments to impart the desired physical properties.
• the filaments average 3 denier, contain 3.5% of the mineral oil, have a tenacity of 2.57 grams per denier, an elongation of 24.5%, and a tensile factor of 12.7.
• Example V The process of Example IV is repeated except that the spin bath contains 0.5% of a composition containing 45.8% of the mineral oil of Example IV, 20% triethanolamine ester of coconut oil acids, 28.5% phosphate of C alkanols averaging C 3.2% triethanolamine, and 2.5% di-tertiaryamyl-phenol.
• the filaments contain 0.9% of the above materials, their tenacity averages 2.49 grams per denier, their elongation 25.3% and their tensile factor 12.5. Control filaments produced without the indicated composition in the bath have a tensile factor of 11.5. When the novel filaments are cut into staple fiber they can easily be processed into spun yarns by conventional equipment. 1
• the process which comprises wet spinning a solution of a cellulose triester into a spin bath including a minor amount of a poly-lower alkylene glycol having a molecular Weight ranging from about 600 to 6000.
• the process which comprises wet spinning a solution of cellulose acetate having an acetyl value of at least about by weight calculated as combined acetic acid in a solvent comprising methylene chloride and up to about 15% by weight of methanol into a spin bath comprising methylene chloride and methanol, the concentration of methylene chloride equalling approximately %:5-the temperature of the spin bath in C., said spin bath including about 0.1 to 3% by weight of white mineral oil having a viscosity at F. of about 30 to 400 Saybolt Universal seconds.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)

Priority Applications (7)

Applications Claiming Priority (3)

Publications (1)

Family

ID=27369486

Family Applications (2)

Family Applications After (1)

Country Status (5)

Cited By (4)

Citations (6)

Family Cites Families (14)

• 0
  • NL NL257294D patent/NL257294A/xx unknown
• 1959
  • 1959-11-03 US US850531A patent/US3109697A/en not_active Expired - Lifetime
• 1960
  • 1960-11-02 DE DE19601469042 patent/DE1469042A1/de active Pending
  • 1960-11-02 GB GB37647/60A patent/GB961400A/en not_active Expired
  • 1960-11-03 FR FR842915A patent/FR1273540A/fr not_active Expired
• 1962
  • 1962-11-07 US US236147A patent/US3267189A/en not_active Expired - Lifetime

Patent Citations (6)

Also Published As

Similar Documents