JP4434796B2 - Fiber modification method - Google Patents

Description

  The present invention relates to a fiber modification method, a modified fiber obtained by the method, and a fiber product produced using the modified fiber.

  Polyurethane elastic yarns are used for various applications because of their special functions. However, since this yarn has a high coefficient of friction, the high-order workability is extremely poor and the touch is also poor. Moreover, it has the fault that dyeing | staining property and dyeing fastness are also low, and a polyurethane elastic thread is not used independently as a stocking use.

  In order to compensate for such drawbacks, a covering yarn in which a nylon yarn is wound around a polyurethane elastic yarn is conceivable and used for stockings and the like. However, the covering yarn becomes thicker as much as the nylon yarn is wound, and when knitted to stockings or the like, it becomes thick and lacks transparency.

  Further, composite yarns having polyurethane as a core and polyamide as a sheath (see, for example, Patent Documents 1, 2, and 3) have been developed. In such a composite yarn structure, it is necessary to make the polyamide component of the sheath as thin as possible in order to maintain the elastic properties of polyurethane. However, in the conjugation method, it is very difficult to control such a core-sheath composite ratio.

  In addition, polyamide fibers such as nylon 6 and 6 are excellent in strength, dyeability, abrasion resistance, etc., but have drawbacks such as low elastic modulus and tendency to wrinkle. On the other hand, polyester fibers are excellent in resilience, heat setting properties, dimensional stability, etc., but have disadvantages such as poor dyeability. In order to compensate for these disadvantages, a composite yarn in which the surface of a polyester fiber is coated with a polyamide polymer has been developed (see, for example, Patent Documents 4 and 5).

However, since polyester and polyamide are incompatible materials, adhesion is poor. Therefore, the core-sheath component is easily peeled off, and the characteristics are not improved.
JP 4-11021 A Japanese Unexamined Patent Publication No. 4-300326 JP-A-8-260246 JP 58-208436 A Japanese Unexamined Patent Publication No. 4-34017

  Therefore, in view of the current state of the prior art described above, the present invention is produced using a method for producing a fiber having a highly adhesive polyamide film on the surface and improved properties, a fiber obtained by the method, and the fiber. The main purpose is to provide a textile product.

  The present invention relates to the following inventions.

1. (1) a step of treating a fiber in a supercritical fluid using a dicarboxylic acid halide; and (2) a fiber treated in the step (1) with a solution containing a diamine or a supercritical fluid to obtain a fiber. A method for producing a fiber having a polyamide film on a surface, comprising a step of forming a polyamide film on a surface.

  2. Item 2. The method according to Item 1, wherein in the step (2), the fiber is treated with a solution containing a diamine.

3. (1) treating the fiber in a supercritical fluid with diamine; and (2) treating the fiber treated in the step (1) with a solution containing a dicarboxylic acid halide or a supercritical fluid, A method for producing a fiber having a polyamide film on a surface, comprising a step of forming a polyamide film on a surface.

  4). Item 4. The method according to Item 3, wherein in the step (2), the fiber is treated with a solution containing a dicarboxylic acid halide.

  5. Item 5. The method according to any one of Items 1 to 4, wherein the substance forming the supercritical fluid is a substance containing at least one selected from the group consisting of water, carbon dioxide, nitrogen, ammonia, hydrocarbons, and alcohols.

  6). Item 6. The method according to any one of Items 1 to 5, wherein the dicarboxylic acid halide is a dicarboxylic acid halide having 2 to 20 carbon atoms.

  7). Item 7. The method according to Item 6, wherein the dicarboxylic acid halide is at least one selected from the group consisting of succinic acid chloride, adipic acid chloride, sebacic acid chloride and dodecanedioic acid chloride.

  8). 8. A fiber coated with a polyamide film obtained by the method according to any one of items 1 to 7.

  9. 9. A fiber product comprising the fiber according to item 8.

  10. Item 10. The textile product according to Item 9, which is stockings.

  In the present invention, the fiber is modified by forming a polyamide film on the surface of the fiber. In order to form a polyamide film on the surface of the fiber in the present invention, the fiber is sequentially treated with a dicarboxylic acid halide and a diamine. The order in which the fibers are treated with dicarboxylic acid halide and diamine is not limited. After treating the fiber with a dicarboxylic acid halide, it may be treated with a diamine or vice versa.

  However, the present invention requires the use of a supercritical fluid at least when treating the fiber with the first compound. This is because the compound can be uniformly and strongly adhered to the fiber surface by the treatment in the supercritical fluid.

  For example, as a first aspect of the present invention, there is a step of treating a fiber with a solution containing a diamine or a supercritical fluid after treating the fiber with a supercritical fluid using a dicarboxylic acid halide. In addition, as a second aspect of the present invention, there is a step of treating the fiber with a supercritical fluid using diamine and then treating the fiber with a solution containing a dicarboxylic acid halide or a supercritical fluid.

Dicarboxylic acid halide The dicarboxylic acid halide used in the present invention is not limited as long as a fiber having a desired effect is obtained. It may be saturated or unsaturated. Further, it may be a straight chain or a branched chain. In the dicarboxylic acid halide, a compound in which both of the two carboxylic acids in the molecule are halogenated is particularly preferred.

  Among dicarboxylic acid halides, it is preferable to use dicarboxylic acid halides having 2 to 20 carbon atoms, preferably 4 to 12 carbon atoms. This is because by using such a dicarboxylic acid halide, a fiber having a uniform polyamide layer firmly adhered to the surface can be obtained.

  More specifically, aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, corkic acid, azelaic acid, sebacic acid, dodecanedioic acid; phthalic acid, isophthalic acid, terephthalic acid And fluorides, chlorides or bromides of aromatic dicarboxylic acids such as naphthalic acid. Among these, when chlorides such as succinic acid, adipic acid, sebacic acid, and dodecanedioic acid are used, fibers having a uniform polyamide layer firmly adhered to the surface are more preferable.

  In this invention, dicarboxylic acid halide can also be used individually by 1 type, and can be used in combination of 2 or more type.

Diamine The diamine used in the present invention is not limited and can be appropriately selected according to the properties of the fiber used as a raw material, the properties desired to be imparted to the fiber when it becomes a polyamide, and the like.

  Examples of the diamine used in the present invention include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10. Examples include aliphatic diamines such as -diaminodecane, and aromatic diamines such as o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, o-xylylenediamine, m-xylylenediamine, and p-xylylenediamine.

  Among these, tetramethylene diamine, hexamethylene diamine, m-xylylenediamine, and the like are more preferable because a polyamide film can be easily formed and the properties of the obtained film are good.

Supercritical fluid A supercritical fluid refers to a fluid under a temperature and pressure exceeding the critical temperature and pressure. A supercritical fluid has high solubility and high diffusivity, and therefore has an advantage that it can easily penetrate into details of fine structures, for example. In addition, the supercritical fluid becomes a gas when the pressure is lowered or the like, whereby there is an advantage that the dissolved matter can be easily separated.

  Thus, in the present invention, a supercritical fluid is used at least when treating the fiber with the initial compound. Further, in this specification, the supercritical fluid includes not only the state of the supercritical fluid but also the state of the subcritical fluid and a state close to these states.

  Examples of the substance forming the supercritical fluid in the present invention include water, carbon dioxide, nitrogen, ammonia, hydrocarbons, alcohols and the like. Examples of the hydrocarbons include ethane, propane, ethylene, propane, propylene, butane, and hexane, and examples of the alcohols include methanol and ethanol. The critical temperatures and critical pressures of these materials are illustrated in Table 1 below.

  Since such a substance becomes a supercritical fluid under conditions of a critical temperature or higher and a critical pressure or higher, conditions may be set as appropriate according to the substance to be used. Of the above substances, carbon dioxide is preferably used. This is because it becomes a supercritical fluid easily, and it is safe from flammability and explosiveness. Further, carbon dioxide is advantageous in that it has an effect of being exhausted in a large amount by the fiber and causing the fiber to expand (particularly, it is a nonpolar hydrophobic material and has a large effect).

  The said substance can also be used individually by 1 type, and can be used in combination of 2 or more type. Furthermore, as long as the effects of the present invention are not impaired, those commonly used as solvents in addition to the above substances can be used as cosolvents. The amount of the cosolvent used is not limited, and can be appropriately selected according to, for example, the type and amount of the substance to be dissolved.

Fiber The fiber used in the present invention may be any of natural fiber, regenerated fiber, semi-synthetic fiber, and synthetic fiber. In addition, these fibers can be used as filaments (monofilaments, multifilaments, modified cross-section yarns, hollow yarns, composite yarns, etc.), spun yarns, woven fabrics, knitted fabrics, nonwoven fabrics, and the like. In the present specification, these are also included as fibers.

  Natural fibers include: (1) Seed hair fibers such as cotton, kapok, and bunya; gin leather fibers such as hemp, cannabis, and jute; leaf fiber fibers such as Manila hemp, sisal hemp, and New Zealand hemp; palm fibers; grass; Plant fibers, (2) eyebrow fibers; animal hair fibers such as wool, goat wool and cashmere; feather fibers; animal fibers such as spider silk.

  Examples of the regenerated fiber include cellulosic regenerated fiber rayon (viscose rayon), cupra (copper ammonia rayon), polynosic and the like.

  Examples of semisynthetic fibers include acetate, triacetate, and promix.

  Examples of the synthetic fiber include polyester, acrylic, aramid, polyvinyl chloride, polypropylene, polyurethane, polyamide-based elastomer, polyester-based elastomer, polyvinylidene, polyethylene, polyclar, fluororesin, biodegradable resin, and the like.

  The said fiber can also be used individually by 1 type, and can also be used in combination of 2 or more type. Among the above fibers, semi-synthetic fibers or synthetic fibers are preferable. This is because it is likely to expand when treated with a supercritical fluid, particularly a supercritical fluid using carbon dioxide.

  More specifically, when using urethane fiber having elasticity for underwear such as stockings (stockings, pantyhose), tights, etc., the method of the present invention can be suitably used for the urethane fiber. it can. Urethane fiber itself has a problem that the frictional resistance is large and the touch is bad. However, if the urethane fiber surface is coated with a polyamide film by the method of the present invention, the touch is drastically improved without impairing the properties of the urethane fiber such as transparency and stretchability.

  The method of the present invention is also suitably used for polyester fibers used as clothing materials for undergarments and outer garments. Polyester fibers have a problem that they can be dyed only with disperse dyes, and disperse dyes have a problem that they gradually discolor. However, such a problem is solved by coating the polyester fiber surface with a polyamide film by the method of the present invention.

  In addition, when a fiber product is manufactured using a blended yarn of polyester and other fibers, and dyeing it, there is a problem that uneven dyeing occurs because the polyester fiber part is difficult to dye. By using the polyester fiber treated by this method, the entire blended yarn can be easily dyed uniformly without impairing the properties of the polyester fiber.

  When other fibers such as silk are used in the method of the present invention, effects such as prevention of wrinkling can be obtained. When used for lame yarn, it can be dyed under mild conditions, so that an effect such as suppression of peeling of the lame film can be obtained.

  In this way, various fibers can be modified by the method of the present invention, and the problems of the fibers can be solved. That is, an excellent fiber product can be obtained by using the modified fiber obtained in the present invention.

Treatment of Fiber (1) First Aspect A first aspect in the method of the present invention will be described below.

  First, the fiber is treated with dicarboxylic acid halide in a supercritical fluid. The fiber and dicarboxylic acid halide may be placed in a high-pressure vessel, and a substance that forms a supercritical fluid may be added thereto. By adding the substance so as to be higher than the critical pressure and setting the temperature in the container to be higher than the critical temperature, the solvent substance becomes a supercritical fluid and can dissolve the dicarboxylic acid halide. The temperature in the container may be set to a critical temperature or higher before filling the solvent substance into the container, or may be raised to the critical temperature or higher while filling the solvent substance or after filling. .

  The material of the high-pressure vessel is not limited as long as it can sufficiently withstand the temperature and pressure above the critical point of the solvent substance. Further, the size of the high-pressure vessel is not limited and can be appropriately selected according to the purpose and conditions.

  The amount of dicarboxylic acid halide used is not limited as long as the desired fiber is obtained. For example, about 0.005 to 1 g, preferably about 0.05 to 0.5 g of dicarboxylic acid halide may be used per 1 g of fiber. By using a dicarboxylic acid halide in this range, the above object can be achieved. When an excess of dicarboxylic acid halide is used relative to the amount of fiber, the excess dicarboxylic acid halide can be reused.

  Furthermore, the time for treating the fiber with the dicarboxylic acid halide is not limited as long as the desired fiber is obtained. For example, it can be appropriately selected according to the material of the fiber, the amount of dicarboxylic acid halide used for the mass of the fiber, etc., and may be about 1 to 120 minutes, preferably about 5 to 60 minutes. If necessary, the treatment may be performed with stirring, or the high-pressure vessel may be shaken.

  After the fiber is treated with the dicarboxylic acid halide as described above, the solvent substance in the high-pressure vessel is gradually discharged from the vessel, and the treated fiber may be taken out.

  The fibers thus obtained are then treated with a solution containing diamine or a supercritical fluid. In the first embodiment, it is more preferable to use the treatment with a solution containing a diamine after the treatment with the dicarboxylic acid halide. This is because the elution of the dicarboxylic acid halide adhering to the fiber can be prevented by the treatment using the supercritical fluid. Further, for example, when a carbon dioxide supercritical fluid is used, a diamine is more easily dissolved in the solution than the supercritical fluid.

  The solvent for the diamine solution may be water, an aqueous solution, or an organic solvent. Since diamine is easily dissolved in water, it is preferable to use water or an aqueous solution as a solvent. Among them, in the first aspect of the present invention, it is preferable to use an aqueous solution made basic with a basic substance such as NaOH. It is because hydrogen chloride produced | generated by superposition | polymerization with dicarboxylic acid halide and diamine can be neutralized by using such aqueous solution. Further, the pH of the aqueous solution is not limited, and can be appropriately selected according to the amount of dicarboxylic acid halide and diamine used.

  The concentration of the diamine is not limited as long as the fiber is sufficiently coated with the polyamide film. For example, it may be about 0.1 to 1.0 mol / L, preferably about 0.3 to 0.7 mol / L.

  The temperature of the diamine solution when treating the fiber with diamine is not limited as long as the fiber is not damaged by the heat of reaction during polymerization. For example, it may be performed at about 30 ° C. or less, preferably about 15 ° C. or less. By performing the treatment at such a relatively low temperature, it is possible to prevent the fiber from being damaged by the heat generated when the diamine and the dicarboxylic acid halide are polymerized.

  Furthermore, the processing time of the fiber is not limited as long as the fiber is sufficiently coated with the polyamide film. For example, the fiber may be immersed in the diamine solution for about 0.1 to 30 minutes, preferably about 1 to 10 minutes. If necessary, it may be immersed under stirring.

(2) Second Aspect In the second aspect of the present invention, first, fibers are treated with diamine in a supercritical fluid, and then treated with a solution containing a dicarboxylic acid halide or a supercritical fluid.

  The treatment with the supercritical fluid can be performed in the same manner as in the first embodiment. The amount of diamine to be used is not limited. For example, it may be about 0.005 to 1 g, preferably about 0.05 to 0.5 g, per 1 g of fiber.

  The supercritical fluid in which diamine is dissolved may be the same as in the first embodiment, but other solvents may be used in combination as a co-solvent in order to increase the solubility. The type of co-solvent is not limited, but for example, when carbon dioxide is used as the supercritical fluid, it is preferable to add water, alcohol (ethanol or the like), or polar organic solvent (acetone or the like). The amount of the co-solvent is not limited as long as the diamine is sufficiently dissolved, and can be appropriately selected.

  The fibers thus obtained are then treated with a solution containing a dicarboxylic acid halide or a supercritical fluid. In the second aspect of the present invention, it is preferable to treat with a solution containing a dicarboxylic acid halide. This is because the diamine can be prevented from eluting into the supercritical fluid. In this case, the fiber remaining after the supercritical fluid is extracted from the high-pressure vessel may be taken out and the fiber may be treated with a dicarboxylic acid halide solution.

  As the solvent for the dicarboxylic acid halide solution, for example, at least one organic solvent selected from the group consisting of normal hexane, carbon tetrachloride, and 1,1,1-trichloroethane can be used. The concentration of the carboxylic acid halide to be used is not limited, but may be, for example, about 0.1 to 1.0 mol / L, preferably about 0.3 to 0.7 mol / L.

  The temperature of the dicarboxylic acid halide solution when treating the fiber is not limited as long as the fiber is not damaged by the heat of reaction during polymerization. For example, it may be performed at about 30 ° C. or less, preferably about 15 ° C. or less. By performing the treatment at such a relatively low temperature, it is possible to prevent the fiber from being damaged by the heat generated when the diamine and the dicarboxylic acid halide are polymerized.

  Moreover, the time which processes a fiber with a dicarboxylic acid solution is not limited, It can select suitably. For example, it may be about 0.1 to 30 minutes, preferably about 1 to 10 minutes.

  The fibers thus obtained can be subjected to treatments such as washing, drying and dyeing as required. In addition, treatment with a softening agent, an antistatic agent, a water repellent agent, an oil repellent agent, an antibacterial agent, a preservative, a fragrance, a pigment, a deodorant and the like can be performed as long as the properties of the fiber obtained in the present invention are not impaired.

Polyamide film The polyamide film formed on the fiber obtained by the above method can be adjusted to a thickness of about 3 μm or less, preferably about 1 μm or less. Further, in the fiber obtained by the method of the present invention, the ratio of the polyamide film to the cross-sectional area of the entire fiber can be adjusted to a very small value of less than 20%, preferably less than 10%.

  That is, according to the method of the present invention, a very thin polyamide film can be obtained along the fiber contour. Therefore, the properties of the film can be newly added without impairing the properties of the fiber on which the film is formed. Moreover, the said film | membrane has very high adhesiveness with respect to a fiber. Therefore, it has high durability against washing.

  For example, when the treatment is performed using urethane fibers, if a polyamide film having a thickness of about 0.1 to 3 μm is formed, the touch is sufficiently improved without substantially impairing the stretchability of the urethane fibers. Moreover, the transparency of urethane fiber is not impaired.

  When the treatment is performed using polyester fibers, if a film having a thickness of about 1 μm or less is formed, the dyeability can be improved without impairing the properties of the polyester fibers.

Fiber Dyeing The fiber coated with a polyamide film obtained above can be dyed by a known method such as dipping in a dye. The method and color for dyeing are not limited and can be appropriately selected according to the purpose. For example, various dyes such as reactive dyes, direct dyes, acid dyes, acid metal-containing dyes, acid mordant dyes, vat dyes, sulfur dyes, disperse dyes, and cationic dyes can be used. Thus, the dyed fiber is also included in the present invention.

Textile products The present invention also includes products made using at least one of the fibers coated with a polyamide coating and the dyed fibers.

  The fiber product is not limited at all. For example, pants, trunks, pantyhose, bra, girdle, tights, socks, shirt, blouse, skirt, suit, slacks, trousers, jeans, cotton bun, coat, blouson, windbreaker, sweatsuit, jersey, muffler, gloves, Mask, cardigan, fleece, down jacket, hat, bib, apron, arm cover, pillow cover, duvet cover, cushion cover, sheets, etc. are included.

  In particular, the polyester fiber is strong, so it is suitable for summer clothing that requires a large number of washings. Moreover, when using the urethane fiber processed by the method of this invention for stockings, since a touch is improved without impairing transparency and a stretching property, it is especially preferable. In this case, the stockings include not only stockings but also pantyhose.

  According to the method of the present invention, since the treatment in the supercritical fluid is included, a fiber having a dense and pinhole-free coating layer is obtained. Moreover, the obtained coating layer is thin and uniform, and the adhesiveness with respect to a fiber is very excellent.

  As a result, when urethane fibers are treated by the method of the present invention, fibers excellent in touch, stretchability, transparency, and the like can be obtained. Further, when used for polyester fibers, since dyes for nylon can be used, a very wide range of dyes can be used, and fibers excellent in fastness can be obtained.

  Furthermore, since the method of the present invention uses a supercritical fluid, the amount of waste liquid can be reduced, the labor for treating the waste liquid can be saved, and the method is environmentally friendly.

  Hereinafter, examples will be shown to further clarify the features of the present invention. The present invention is not limited to these examples.

Example 1
As the fiber to be subjected to the surface treatment, urethane fiber (40d / 4f) knitted into a cylindrical knitted shape was used. 2 g of this dough and 0.5 g of sebacic acid chloride were placed in a high-pressure container having an internal volume of 500 ml, and the temperature was raised to 50 ° C. while injecting carbon dioxide into the container. Further, carbon dioxide was continuously injected while maintaining the temperature, and the pressure was set to 20 MPa.

  This state was maintained for 15 hours, and carbon dioxide in the high-pressure vessel was discharged. The dough was taken out from the high-pressure vessel and impregnated with 0.5 mol / L hexamethylenediamine basic aqueous solution (aqueous solution adjusted to 50 ml by adding 0.5 mol / L NaOH aqueous solution to 2.91 g hexamethylenediamine) for 30 seconds. Thereafter, it was thoroughly washed with water and dried.

Example 2
The experiment was performed in the same manner as in Example 1 except that 0.75 g of sebacic acid chloride was used.

Comparative Example 1
No treatment was applied to the dough used in Example 1.

Comparative Example 2
No treatment was performed except that a urethane fiber (20d / 2f) covered with a nylon fiber (12d / 7f) was knitted into a cylindrical knitted shape.

Comparative Example 3
Urethane / nylon eccentric composite yarn (28d / 2f) was made into a cylindrical knitted shape and was not subjected to any treatment.

Comparative Example 4
After impregnating 2 g of fabric knitted with urethane fibers (40d / 4f) into a cylindrical knitted shape for 1 minute in a normal hexane solution of 0.25 mol / L sebacic acid chloride, impregnating with an aqueous hexamethylenediamine solution, washing thoroughly with water, Dried.

Test example 1
Various tests were performed using the fibers obtained in Examples 1-2 and Comparative Examples 1-4.

  The elongation was measured with an autograph manufactured by Shimadzu Corporation. The touch, transparency, and supportability (stretchability) were expressed as an average of 5 points by 8 monitors (the higher the score, the better the performance). For the adhesion of the nylon film, each sample was stretched several times, and the state of the film was observed. The obtained results are shown in Tables 2 to 4 below.

  From Table 2, the urethane fiber (Examples 1 and 2) coated with the polyamide film by the method of the present invention did not significantly reduce the elongation compared to the untreated urethane fiber (Comparative Example 1) (sufficiently) It is understood that the touch is very good.

  From Table 3, it can be seen that the urethane fiber coated with the polyamide film by the method of the present invention is excellent in supportability (stretchability) and transparency (Examples 1 and 2). In contrast, the covering yarn is inferior in transparency (Comparative Example 2), and the eccentric composite yarn is inferior in supportability (Comparative Example 3).

  When the fiber was treated with sebacic acid chloride in a supercritical fluid and then treated with a diamine solution, the fiber was stretched several times, but the polyamide film was not peeled off. Therefore, it can be seen that when the fiber is treated by the method of the present invention, the adhesion of the polyamide film to the fiber is very high (Examples 1 and 2 in Table 3).

  However, in the yarn (fabric) treated with a normal hexane solution of sebacic acid chloride and then treated with a diamine solution, the polyamide film peeled off the fiber very easily when the fiber was stretched. Therefore, it can be seen that the adhesion of the polyamide film is very poor (Comparative Example 1 in Table 3).

Example 3
An experiment was performed in the same manner as in Example 1 except that polyethylene terephthalate (PET) woven fabric for dyeing fastness test manufactured by Japan Standards Association was used instead of urethane fiber as the fiber used for coating.

Comparative Example 5
No treatment was performed on the PET woven fabric for dyeing fastness test manufactured by Japan Standards Association.

Comparative Example 6
An experiment was performed in the same manner as in Comparative Example 4 except that a polyethylene woven fabric for dyeing fastness test manufactured by Japan Standards Association was used instead of urethane fiber as the fiber used for coating.

Test example 2
Using the fibers obtained in Example 3 and Comparative Examples 5 to 6, the following various tests were performed.

  The dyeability is dyed with a blue acid dye (Nairosan Blue NL) and a blue reactive dye (ReaNova Blue CA Gran), respectively, and then a color difference meter CR-321 manufactured by Minolta Co. The lower the numerical value, the deeper the bluish color.).

  The adhesion of the polyamide coating was confirmed by bending the sample fabric and rubbing the surfaces of the fabric to determine whether the polyamide coating was peeled off.

  From Table 5, it can be seen that the dyeability is remarkably increased by coating the PET surface with a polyamide film by the method of the present invention.

  Table 6 also shows that when the polyamide film is coated on the PET surface by the method of the present invention, very high adhesion can be obtained.

Test example 3
Experiments were conducted in the same manner as in Example 3 using succinic acid chloride (carbon number 4) and adipic acid chloride (carbon number 6) instead of sebacic acid chloride (carbon number 10). When the obtained fiber was dyed with an acid dye (Nirosan Blue NL), it was confirmed that all the fibers were dyed blue (b value was -15.8 for succinic acid chloride, and b for adipic acid chloride). The value is -20.4.) Among these, the more the carbon number, the deeper the color.

2 shows an electron micrograph of the cross section of the fiber obtained in Example 1. FIG. 2 shows an electron micrograph of a part of the cross section of the fiber obtained in Example 1. FIG. 2 shows an electron micrograph of the cross section of the fiber obtained in Example 2. FIG. 2 shows an electron micrograph of a part of the cross section of the fiber obtained in Example 2. FIG. 2 shows an electron micrograph of a cross section of the fiber obtained in Comparative Example 1. An electron micrograph of a part of the cross section of the fiber obtained in Comparative Example 1 is shown.

Claims (8)

(1) a step of treating a fiber in a supercritical fluid using a dicarboxylic acid halide; and (2) a fiber treated in the step (1) with a solution containing a diamine or a supercritical fluid to obtain a fiber. A method for producing a fiber having a polyamide film on a surface, comprising a step of forming a polyamide film on a surface ,
In the step (2), the fiber is treated with a solution containing a diamine . (1) treating the fiber in a supercritical fluid with diamine; and (2) treating the fiber treated in the step (1) with a solution containing a dicarboxylic acid halide or a supercritical fluid, A method for producing a fiber having a polyamide film on a surface, comprising a step of forming a polyamide film on a surface , wherein the fiber is treated with a solution containing a dicarboxylic acid halide in step (2). The manufacturing method characterized by this . 3. The method according to claim 1, wherein the substance forming the supercritical fluid is a substance containing at least one selected from the group consisting of water, carbon dioxide, nitrogen, ammonia, hydrocarbons, and alcohols. The method according to any one of claims 1 to 3 , wherein the dicarboxylic acid halide is a dicarboxylic acid halide having 2 to 20 carbon atoms. The method according to claim 4 , wherein the dicarboxylic acid halide is at least one selected from the group consisting of succinic acid chloride, adipic acid chloride, sebacic acid chloride and dodecanedioic acid chloride. A fiber coated with a polyamide film, obtained by the method according to any one of claims 1 to 5 . A textile product comprising the fiber according to claim 6 . The textile product according to claim 7 , which is stockings.

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