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
  • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
  • D01F6/58—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products
  • D01F6/60—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products from polyamides
  • D01F6/605—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products from polyamides from aromatic polyamides

Definitions

• the present invention relates to para system aramide fiber and method for producing the same.
• Polyparaphenylene terephthalamide fiber (hereinafter, referred to as para system aramide fiber) is a synthetic fiber having high functions such as of high strength, high modulus elasticity, high thermal resistance, non-electro-conductivity, and no rust occurrence, as well as having flexibility and lightweight property, which are characteristics of organic fibers. From these properties, it is used as a reinforcement material for a tire for a motorcar, a motorcycle and a bicycle, a timing belt for a motorcar, a conveyer and the like. Further, it is also used for reinforcing an optical fiber cable, and as a rope. Furthermore, it is also applied to a bulletproof jacket, protection clothes which are formed as working gloves and working clothes by utilizing the feature being hard to be cut against an edged tool, and clothes for fire fighting formed by utilizing the feature being hard to burn.
• JP-A-SHO 50-12322 proposes a method for diffusing additives such as dye, antioxidant, ultraviolet insulation agent, and fireproofing agent in a fiber expanded by water.
• JP-A-SHO 50-12322 does not describe with respect to diffusion of all kinds of dyes into fibers, and also does not specify the conditions. Especially, it does not describe dyeing under a condition of a water content of 50% or less.
• JP-A-SHO 54-59476 discloses a method for dyeing from buckling portions of a fiber after providing crimps to the fiber at 10 crimps/inch or more. Further, JP-A-HEI 2-41414 discloses a method for adding an organic pigment to a dope for spinning. JP-A-SHO 63-145412 proposes a method for introducing para oriented aramide into a process, in which the tension is relaxed, at a coagulation step immediately after spinning, thereby bringing it into contact with a dyeing solution.
• JP-A-HEI 7-258980 proposes a method for bringing para system aromatic polyamide, whose inherent viscosity is 2.5 dl/g or less and which is expanded by water, into contact with a dyeing solution.
• JP-A-HEI 8-260362 discloses a method for dyeing by a cation system dye at a temperature of 130 °C or higher, while using a fiber expansion agent.
• JP-A-HEI 5-209372 discloses a method for dyeing a copolymerized para system aramide fiber at a temperature of 160 °C or higher by using a dispersed dye having a molecular weight of 400 or less.
• JP-A-HEI 9-87978 and JP-A-HEI 9-87979 propose a method for dyeing a para system aramide fiber under a condition of a high pressure and a temperature of 200 °C after treating it with a polar solvent such as dimethylsulfoxide.
• JP-A-SHO 54-59476 for a high-strength and rigid para system aramide fiber, it is difficult to provide crimps at 10 crimps/inch or more, and this method is restricted for a formation of a staple.
• the method disclosed in JP-A-HEI 2-41414 is a proposal for a so-called originally colored spinning, and the method described in JP-A-SHO 63-145412 is a method for bringing a fiber into contact with a dye solution at a tension-free condition without winding it after spinning. In any method, a fairly large volume of production per one color is required, and the color employed is limited.
• JP-A-HEI 7-258980 the strength of a fiber is extremely low because of a low viscosity of the polymer, and therefore, the method cannot satisfy the feature of high strength which aramide fiber essentially has.
• the method disclosed in JP-A-HEI 8-260362 is a proposal for a spun yarn, which is inferior to a filamentary yarn in tensile strength and tensile elastic modulus, and therefore, it is not satisfied as a method for dyeing a filament capable of utilizing the function of a high strength and a high elastic modulus of original aramide fiber.
• JP-A-HEI 5-209372, JP-A-HEI 9-87978 and JP-A-HEI 9-87979 are not common, because they require special equipment such as one for recovery of a polar solvent or for high-temperature dyeing.
• a method for post-dyeing capable of applying various colors at a form of a filament which can maintain the features of high-strength and high-elastic modulus of aramide fiber, namely, a method for dyeing various colors in a dyeing process, capable of dyeing at respective colors individually from each other, separatedly and after a process in which a spun filament is once wound onto a tube-like material, has not yet been realized.
• a yarn forming process for forming a filamentary yarn and a dyeing process for dyeing the yarn generally are separated from each other, and the respective processes are performed by respective technical experts using respective exclusive equipment. To satisfy severe requirements of customers as to colors of dyed textile products, it is important to break off the process once after producing fibers, and to transport the fibers to a plant for dyeing and dye the fibers in respective colors, that customers require, by technical experts for dyeing.
• the present invention takes the following ways.
• a polyparaphenylene terephthalamide (hereinafter, also referred to as "PPTA") according to the present invention is a polymer obtained by polycondensation of terephthalic acid and paraphenylenediamine, and a small amount of dicarboxylic acid and diamine may be copolymerized.
• Polyparaphenylene terephthalamide fiber (hereinafter, referred to as "para system aramide fiber") according to the present invention is produced by making an optically anisotropic dope from PPTA having an inherent viscosity ( ⁇ inh) of 5 or more and a concentrated sulphuric acid, once spinning the dope in air through fine holes of a spinning die, immediately thereafter, introducing the spun dope into water to coagulate it, introducing it into a Nelson roller and neutralizing it in a sodium hydroxide solution, slightly drying it by a hot roller after a water washing process, and passing it through a process for continuously winding it on a tube as a filament.
• ⁇ inh inherent viscosity
• Para system aramide fiber wound is wrapped by a wrapping material such as a polyethylene film so as to prevent it from being dried before being sent to a drying process.
• the crystallinity of the para system aramide fiber in this step is 50% or less.
• the tensile modulus elasticity of the fiber is over 400 g/denier and it has a feature as a high-modulus elasticity fiber, in order to further increase the modulus elasticity, the fiber is heat treated at a temperature of 350 to 400°C for 5 to 10 seconds after drying, and by this treatment, the crystallinity is generally increased up to a degree over 50%.
• the inherent viscosity ( ⁇ inh) of PPTA used in the present invention is preferably 5 or more. If the inherent viscosity ( ⁇ inh) is less than 5, it is hard to obtain the fiber properties of high strength and high modulus elasticity.
• the crystal size (110 direction) is in a range of 30 to 55 angstroms and the water content is always more than 8%. If the crystal size is less than 30 angstroms, it is difficult to sufficiently densify the fiber and to achieve the fiber properties of high strength and high modulus elasticity, and if the crystal size is more than 50 angstroms, it is difficult to dye.
• the water content is always more than 8% means that it has no history of a treatment that has dried it at a water content of 8% or less. If the fiber is dried at a water content of 8% or less, the structure is too densified and it becomes hard to dye it. In such a condition, even if water is provided again, the dyeability cannot be recovered.
• the water content of para system aramide fiber is in a range of 15 to 49%. If the water content is 50% or more, it is difficult to wind the fiber because the frictional resistance between the fiber and guide rolls and the like becomes great. To control such a preferable water content, it is desired to dry the spun para system aramide fiber at a hot roller temperature of 100 to 150 °C for 5 to 20 seconds. If drying temperature is lower than 100°C, it is difficult to remove water, and occurs a problem in handling after winding the fiber onto a tube. If higher than 150 °C, it is difficult to dye because the crystallinity is too accelerated.
• para system aramide fiber having such properties is served to a dyeing treatment.
• a particular apparatus and a particular method are not required, and an existing apparatus for dyeing synthetic fibers can be used.
• the dyeing is achieved by controlling pH by adding an assistant and an acid to a proper amount of dye, starting to dye at, for example, 60°C, elevating the temperature to 130°C for 60 minutes, and dyeing for 30 minutes.
• a cation dye which easily permeates even into a dense structure of fiber, is most desirable.
• Para system aramide fiber according to the present invention is useful to various applications.
• Dyed para system aramide fiber filament can be used as machine cottons, cords, ropes and woven fabrics with various colors.
• Para system aramide fiber fabrics with various colors obtained by the present invention can be used for clothing for sports, bag texture, working clothes, clothes for fire fighting, and various kinds of protection clothes, tents clothes and other applications.
• a texture for bulletproof jacket dyed in an inconspicuous color even if the outer skin is broken by shot and the para system aramide fiber used as a bulletproof texture is exposed, it is not conspicuous.
• dyed para system aramide fiber according to the present invention As products applied with dyed para system aramide fiber according to the present invention, seat belts for motorcars, protection clothes for speedboat race players, bowstrings, tennis guts, fishing lines and the like can be raised.
• dyed para system aramide fiber according to the present invention is used as a reinforcing material of a transparent or semi-transparent resin, it may be produced as a colorful resin product because the colored reinforcing material can be seen through the transparent or semi-transparent resin.
• a structure can be employed for a glass frame made from resin, a frame of tennis racket, a hockey stick, a fishing rod, a golf shaft and the like.
• Para system aramide fiber according to the present invention can be applied to ropes or electric wires whose production year is indicated by colors.
• reinforcement of each electric wire and discrimination of a terminal of each electric wire can be both achieved by using reinforcing materials having the respective colors different from each other. It can also be used for a so-called lip cord, in which the fiber is provided under the covering material of the electric wire and the covering material can be cut by using the fiber to expose the wire terminal.
• a colored para system aramide fiber staple can be obtained by passing a dyed para system aramide fiber filament through a crimper to provide 4 to 9 crimps/25mm (for example, 6 crimps/inch) similarly to that in commercial para system aramide fibers, and cutting the crimped fiber at a length suitable for spinning, namely, at a length of 20 to 150 mm.
• the dyed para system aramide fiber can be made as flocks for electrical flocking by cutting it at a length of 1 to 3 mm without crimping. In the present invention, it may be performed that para system aramide fiber before dyeing is crimped and cut, and after making a staple, it is dyed. Similarly, it may be performed that the fiber is dyed after being cut to make flocks for electrical flocking.
• Inherent viscosity ( ⁇ inh) is determined by a regular method, using a solution in which a polymer is dissolved in a concentrated sulphuric acid with a concentration of 98.5 wt% at a polymer concentration (C) of 0.5 g/dl and at a temperature of 30°C.
• ⁇ inh ( ln ⁇ ⁇ rel)/C
• Tensile strength and tensile modulus elasticity (initial tensile resistance) of fiber are determined according to JIS-L-1013.
• L value is determined according to JIS-Z-8729.
• Macbeth Color Eyes 3000 produced by Sumika Bunseki Center Corporation is used.
• dried para system aramide fiber B (filamentary yarn) was produced by introducing the para system aramide fiber A, without winding, into a following hot roller to further heat treat it at a temperature of 350 °C for 10 seconds, and thereafter, winding it.
• a sample of the para system aramide fiber was taken by a weight of 10 g as a weight converted into absolute dried condition, it was started to be dyed at a condition of a bath ratio of 1:15 and a temperature of 60 °C, the temperature was elevated up to 130°C for 60 minutes, and it was dyed for 30 minutes. After dyeing, it was served to reduction cleaning in a bath of an anti-ion active agent and a reductant at 80 °C for 20 minutes, and after dehydrated and dried, L value was determined. The smaller the L value is, the smaller the reflection of a light is and the darker the color tone is. In a case of an identical color, the smaller the L value is, the better it is dyed. In the dyeing method using the dyeing bath prepared in the above-described manner, a grade of 50 or less in L value was determined to be well-dyed.
• Para system aramide fiber A adsorbed the dye well, but para system aramide fiber B almost was not dyed.
• Para system aramide fiber A was left at a room temperature to release water, the water content before dyeing was varied, and then it was dyed at the same condition as that of the above-described Example.
• the fibers were well dyed except in Comparative Example 2 of a water content of 5 %. Comparative Example 3:
• Para system aramide fiber A was dyed under the aforementioned condition after the water content before dyeing had been controlled at 0 % by drying the fiber at 100°C for 60 minutes using a circulation type hot-air dryer. However, it almost was not dyed.
• the yarn of para system aramide fiber A was wound, without adding a twist to the yarn, onto a plastic tube at a tension of 0.04 g/denier, which tube has an inner diameter of 51 mm, an outer diameter of 57 mm and a length of 250 mm length and has many holes each having a diameter of 8 mm on the portion that the yarn is to be wound.
• the amount of winding was set at 1 kg as a weight in absolute dried condition. It was dyed under the aforementioned condition, using a cheese-dyeing apparatus, in which a dyeing solution was circulated from the holes defined on the plastic tube to the outside of the cheese through the yarn.
• the water content of the para system aramide fiber before dyeing determined was 48 %.
• This twisted yarn was cheese-dyed in the same manner as that of Example 5. Because the filamentary yarn had a circular section by the twisting and a space was formed between yarns at a state wound on a plastic tube, the circulation of the dyeing solution during dyeing was better than that in Example 5. However, partially there occurred an insufficient dyeing portion having a low concentration.
• a polyparaphenylene terephthalamide fiber which can be dyed while its properties of high strength and high modulus elasticity are maintained, and a polyparaphenylene terephthalamide fiber dyed in a variety of colors, can be provided.
• a polyparaphenylene terephthalamide fiber which can be dyed while its properties of high strength and high modulus elasticity are maintained, and a polyparaphenylene terephthalamide fiber dyed in a variety of colors, can be provided.
• the para system aramide fiber according to the present invention is suitable for various applications, especially the dyed para system aramide fiber filament can be used as machine cottons, cords, ropes and textiles with various colors.
• Para system aramide fiber textile with various colors according to the present invention can be used as clothing for sports, bag texture, working clothes, clothes for fire fighting, and various kinds of protection clothes, tents clothes and other applications.

Landscapes

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

Applications Claiming Priority (2)

Publications (4)

Family

ID=26440122

Family Applications (1)

Country Status (7)

Cited By (1)

Families Citing this family (7)

Family Cites Families (7)

• 1999
  • 1999-04-26 BR BRPI9911583-2A patent/BR9911583B1/pt not_active IP Right Cessation
  • 1999-04-26 CN CN99810113.3A patent/CN1205365C/zh not_active Expired - Fee Related
  • 1999-04-26 WO PCT/JP1999/002195 patent/WO2000065135A1/fr not_active Ceased
  • 1999-04-26 AU AU35363/99A patent/AU763815B2/en not_active Ceased
  • 1999-04-26 EP EP99917147A patent/EP1101843B2/fr not_active Expired - Lifetime
  • 1999-04-26 AT AT99917147T patent/ATE399890T1/de not_active IP Right Cessation
  • 1999-04-26 CA CA002336245A patent/CA2336245C/fr not_active Expired - Fee Related

Also Published As

Similar Documents

Legal Events