JP2008261070A - Polypropylene-based fiber and woven or knitted fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polypropylene-based fiber which can provide a dyed product in deep color with a dispersion dye in dying of post-treatment step and having good light fastness and chlorine fastness, and a woven or knitted fabric including the fiber. <P>SOLUTION: The polypropylene-based fiber has a core-sheath composite structure in which a core part includes a thermoplastic resin expressing dyeability with a dispersion dye and a sheath part includes a polypropylene-based resin, and has a monofilament fineness of 1.5-10 dtex and a thickness of the sheath part in fiber cross-section of ≤12 μm. The woven or knitted fabric includes the propylene-based fiber. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a polypropylene-based fiber capable of obtaining a dyed product with a disperse dye by a dyeing process in a post-processing step, and a woven or knitted fabric including the fiber.

  2. Description of the Related Art Polypropylene fibers have been used in various industrial applications such as curing sheets, mesh sheets for building construction, and carpet yarns because they are excellent in light weight, water repellency, and easy recyclability. However, since the polypropylene resin constituting the polypropylene fiber cannot be dyed with disperse dyes commonly used for polyester fibers, it is difficult to use the polypropylene fiber for a dyeing process in a post-processing step such as clothing. there were.

  For this reason, development of a polypropylene fiber that can be dyed in a post-processing step has been conventionally performed. For example, Patent Document 1 or 2 proposes a method in which a dyeable resin is dispersed in a polyolefin resin that constitutes a polyolefin fiber. Polyesters such as polyethylene terephthalate and polybutylene terephthalate are used as the dyeable resin. Resin is shown.

  However, in these proposed methods, if the polyester resin necessary for obtaining sufficient dyeability is added, the spinning stability is lowered, so it is difficult to increase the amount of the polyester resin added. If the stability was ensured, sufficient dyeability could not be obtained, and the spinning stability was insufficient due to poor compatibility between the polyolefin resin and the polyester resin. Furthermore, the light fastness of the dyed product is not at a satisfactory level as a textile for clothing, and there have been problems such as discoloration and fading when used for a long time.

  Patent Document 3 or 4 proposes to use a polypropylene fiber or polyolefin fiber having a core-sheath composite, but the light fastness of the dyed product is not at a satisfactory level as a textile for clothing, There have been problems such as discoloration and fading when used for a long time.

JP-A-4-209824 JP-A-6-25912 Japanese Patent Laid-Open No. 7-48720 JP 2002-214019 A

  The present invention was made as a result of studies to solve the problem in dyeing by core-sheath composite without modifying the polypropylene resin itself constituting the polypropylene fiber, and the object of the present invention is a post-processing step It is an object of the present invention to provide a polypropylene fiber and a woven or knitted fabric including the fiber, which can obtain a dyed product having a deep color with a disperse dye and a good light fastness and chlorine fastness by dyeing.

The first gist of the present invention resides in a polypropylene fiber having a core-sheath composite structure and having the following requirements (1) to (4).
(1) Thermoplastic resin whose core part is dispersible dyeable (2) Sheath part is a polypropylene resin (3) Single fiber fineness is 1.5 to 10 dtex
(4) The thickness of the sheath part in the fiber cross section is 12 μm or less. The second gist of the present invention resides in the woven or knitted fabric containing the polypropylene fiber.

  The polypropylene fiber of the present invention can be obtained without any problem in the stability of the spinning process, and according to the present invention, it is dark and light-resistant by a disperse dye in the dyeing process of the post-processing process without depending on the original deposition. A polypropylene fiber capable of obtaining a dyed product excellent in fastness can be provided, and the polypropylene fiber of the present invention is used as a material for woven or knitted fabrics such as carpets and other upholstered fabrics or for clothing. In particular, since it becomes possible to easily obtain fine fibers, it can be suitably used for materials for clothing such as socks and sports inners. Furthermore, since it is excellent in chlorine fastness, it can be suitably used for swimwear applications.

  The polypropylene fiber of the present invention has a core-sheath composite structure, the core is composed of a thermoplastic resin exhibiting disperse dye dyeability, and the sheath is composed of a polypropylene resin that is not normally dyed with a disperse dye. It is necessary to The thermoplastic resin constituting the core part is a thermoplastic resin exhibiting dyeability with disperse dyes, and examples thereof include polyester resins, polyamide resins, etc., but are polyester resins from the standpoint of obtaining deep dyeability. It is preferable.

  The polyester resin may be either an aromatic polyester or an aliphatic polyester. The aromatic polyester as used herein refers to terephthalic acid or an ester-forming derivative thereof as a dicarboxylic acid component, and at least one selected from ethylene glycol and 1,4-butanediol or an ester-forming derivative thereof as a diol component. The polyester to be used is representative, but a part of the dicarboxylic acid component may be replaced with another dicarboxylic acid, or a part of the diol component may be replaced with another diol.

  Other dicarboxylic acids that can be substituted include isophthalic acid, monoalkali metal salts of S-sulfoisophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfone dicarboxylic acid, adipic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid And the like, and oxycarboxylic acids such as p-oxybenzoic acid and p-β-oxyethoxybenzoic acid or esters thereof.

  Other diols that can be replaced include alkylene glycols having 2 to 10 carbon atoms, 1,4-cyclohexanedimethanol, neopentyl glycol, 1,4-bis (β-oxyethoxy) benzene, and bisglycol A bisglycol. Examples include ether polyalkylene glycol.

  Furthermore, within the range in which the polyester resin is substantially linear, polycarboxylic acids such as trimellitic acid and pyromellitic acid, polyols such as pentaerythritol, trimethylolpropane, and glycerin, monohydric polyalkylene oxide, phenyl A polymerization terminator such as acetic acid may be used.

  In addition, the aliphatic polyester as used in the present invention refers to a polymer in which aliphatic alkyl chains are linked by an ester bond, such as polylactic acid, polyhydroxybutyrate, polybutylene succinate, polyglycolic acid, polycaprolactone, and the like. Is mentioned.

  Such a polyester resin may be synthesized by a known method. For example, when describing polyethylene terephthalate, terephthalic acid and ethylene glycol are directly esterified, or a lower alkyl ester of terephthalic acid such as dimethyl terephthalate is transesterified with ethylene glycol, or terephthalic acid is treated with ethylene. A general method is to synthesize a glycol ester of terephthalic acid and / or a low polymer thereof by addition reaction of oxide and then polycondensate by a conventional method. Furthermore, in the synthesis of polyester, known catalysts, antioxidants, anti-coloring agents, ether bond by-product inhibitors, flame retardants and the like can be used as appropriate.

  If the thermoplastic resin constituting the core part is dyeable to disperse dyes, it is dyeable to dyes other than disperse dyes, for example, cationic dyes such as basic dyes and anionic dyes such as acid dyes. It may be a thermoplastic resin such as a modified polyester resin or a polyamide resin that is dyeable to an anionic dye. However, if it is a thermoplastic resin that is not dyeable to disperse dyes, it will form the sheath even if it is going to be dyed with a cationic dye or an anionic dye in the post-processing step of the fiber that has formed the core with this resin. Since the polypropylene resin is hydrophobic, the cationic dye and the anionic dye do not penetrate to the core, and the thermoplastic resin constituting the core is not dyed.

  As the polypropylene-based resin constituting the sheath, a resin containing propylene as a main component, preferably containing 90% by mass or more of propylene is used. As such a polypropylene-based resin, for example, polypropylene, propylene and ethylene, which are propylene homopolymers, A copolymer with butene-1 or the like, or a mixed polymer of a combination of two or more of these may be mentioned, and a polypropylene single resin is particularly preferred. These polypropylene resins may contain antioxidants, stabilizers, etc. such as hindered phenol compounds, phosphorus compounds, hydroxylamine compounds, hindered amine compounds, or the like, fiber texture, gloss, etc. In order to improve the above, fine particles such as titanium oxide, silica and barium sulfate may be added. In addition, these polypropylene resins preferably have a melt flow rate value of 7 to 60 g / 10 min from the viewpoint of yarn production.

   Further, the polypropylene resin constituting the sheath may be a mixed resin having a mass ratio of polypropylene and polyester resin in the range of 99.5 / 0.5 to 90/10. It plays an auxiliary or direct role to impart disperse dyeability to the sheath, and when dyeing the fiber of the present invention with disperse dye, a darker dyed product can be obtained. The polyester resin to be mixed may be the same as or different from the polyester resin constituting the core. When the ratio of the polyester resin exceeds the above range, the effect of imparting disperse dyeability increases, but the polyester resin is peeled or dropped during stretching in the spinning process, which causes a problem in spinning.

  The polypropylene fiber of the present invention has a core-sheath composite structure, and the single fiber fineness is required to be in the range of 1.5 to 10 dtex, and preferably 2 to 5 dtex. In addition, the polypropylene fiber of the present invention requires that the thickness of the sheath portion made of the polypropylene resin in the fiber cross section is not more than 12 μm, and further passes through processing steps such as false twisting. When ensuring, it is preferable that it is 2-6 micrometers. When the thickness of the sheath portion is less than 2 μm, abrasion damage such as peeling off of the sheath portion is likely to occur in a processing step such as false twisting. The cross-sectional shape of the polypropylene fiber of the present invention is not particularly limited, but a circular cross-section is preferable for obtaining a dark coloring effect in the dyeing process.

  The polypropylene fiber of the present invention is a dyeing process using a disperse dye in a post-processing step, and a dyed product having a dyeing density equivalent to that of a fiber made of a thermoplastic resin constituting the core, preferably a polyester resin, is obtained. This dyeing effect is exhibited because the sheath part is made of a polypropylene resin that is not dyed with disperse dye, but the sheath part is extremely thin, so that the disperse dye penetrates into the core part through the thin film. Even if various additives are included in the polypropylene resin of the sheath part, the transparency of the sheath part is extremely thin and high in transparency. This is because the color density at which the core is dyed can be seen from the outside as it is.

  The dyeing process using a disperse dye is performed according to the dyeing conditions of a thermoplastic fiber constituting the core, preferably a polyester fiber made of a polyester resin. For example, when the core is made of a polyester-based resin, atmospheric dyeing with a disperse dye can be employed, and the dyeing temperature is 98 to 100 ° C boiling temperature and the dyeing time is 30 to 60 minutes. Dyeing can be performed.

  In order to produce the polypropylene fiber of the present invention, for example, a thermoplastic resin showing disperse dye dyeability as a core component, preferably a disperse dye dyeable polyester resin, and a polypropylene resin as a sheath component are used. The core component and the sheath component are respectively charged into the extruder of each component of the core-sheath compound melt spinning machine, and the extruder temperature is extruded as the temperature at which the component having the higher melting point is melted. A polymer is discharged from a core-sheath composite spinning nozzle having a diameter of 6 mm and a hole number of 12 to 30 at a total discharge rate of the core component and the sheath component of 7 to 29 g / min. Depending on the discharge rate, the winding speed is preferably 800 to 1500 m / min. And unstretched yarn is stretched 1.8 to 3.0 times in contact with a heated body having a temperature of 80 to 120 ° C., and the single fiber fineness is 1.5 to 10 dtex, preferably 2 ~ 5dtex Get as a multi-filament yarn. In spinning, it is preferable to spin into a circular fiber cross-sectional shape in order to obtain a uniform sheath thickness.

  Hereinafter, the present invention will be specifically described by way of examples. In addition, the measurement of the sheath part thickness of the fiber, the dyed color density measurement, and the fastness measurement in the examples were based on the following methods.

(Evaluation samples such as dyeability)
A fiber knitted fabric is prepared, and after atmospheric dyeing with a disperse dye under the following conditions, soaped with Emulgen 900 (manufactured by Kao Corporation, surfactant) 1 g / L, washed with water, air dried, and this dyed product is evaluated. A sample was used.
Dyeing conditions:
Dianics Black BG-FS 200% 01 (Dystar Japan, black disperse dye) 2% (weight to fiber)
Dispa-TL (made by Meisei Chemical Co., Ltd., dyeing assistant) 0.7cc / L
Ultra MT (Daiwa Chemical Industry Co., Ltd., dyeing assistant (neutralizing agent)) 0.55cc / L
Bath ratio 1:30
Temperature 98-100 ° C
30 minutes

(Measurement of fiber sheath thickness)
Single fibers were collected from the evaluation sample, and the fiber cross section of the single fibers was observed with an optical microscope at a magnification of 400 times, and obtained from the measured values of the diameter of the single fibers and the diameter of the core.

(Measurement of dyed product color density (L value))
L value was measured for the said evaluation sample using Color-Eye 7000A (The color difference measuring machine by Gretag Macbeth). The measurement was performed 3 times, and the average value was obtained as the L value. The L value represents lightness, and the darker the color, the smaller the value.

(Measurement of light fastness)
The evaluation sample is exposed in accordance with JIS L-0841 7.2 (c) third exposure method, a test with an ultraviolet carbon arc lamp according to JIS L-0842 is performed, and the test sample is compared and determined in gray scale. did.

(Measurement of chlorine fastness)
The said evaluation sample was tested based on D method which is a test by the chlorinated water of JISL-0884, and the test sample was compared and determined by the gray scale.

Example 1
Polybutylene terephthalate (manufactured by Changchun Co., Ltd. (PBT)) is used as the core component, polypropylene (PP) is used as the sheath component, and the core component and sheath component are respectively supplied to the single screw extruder of each component of the core-sheath compound melt spinning machine. The extrusion temperature was 260 ° C., and the discharge rate was 13.6 g / min (core component discharge rate 3.4 g / min) from the core-sheath compound spinning nozzle with a spinning nozzle temperature of 260 ° C., a hole diameter of 0.6 mm, and a hole number of 24. The polymer was discharged at a sheath component discharge rate of 10.2 g / min), and an undrawn yarn was obtained at a winding speed of 1000 m / min. The undrawn yarn was drawn 2.45 times at a final drawing speed of 400 m / min with a heating roller at a temperature of 90 ° C. and a hot plate at a temperature of 120 ° C. to obtain a multifilament of 56 dtex / 24 filaments. The yarn-making properties in obtaining this multifilament were good, and the measurement results of single fiber fineness (dpf), single fiber sheath thickness, dyed color density (L value), and fastness of the obtained multifilament are shown in Table 1. Indicated. In Table 1, “o” of fastness means excellent.

(Example 2)
In Example 1, the core-sheath compound spinning nozzle is discharged to a core-sheath compound spinning nozzle having a hole diameter of 0.4 mm and the number of holes of 12, and the discharge rate is 8.8 g / min (core component discharge rate 2.2 g / min, sheath component discharge). An undrawn yarn was obtained in the same manner as in Example 1 except that the amount was changed to 6.6 g / min) and the winding speed was changed to 1400 m / min. This undrawn yarn was drawn 1.93 times with a heating roller having a temperature of 90 ° C. at a final drawing speed of 400 m / min to obtain a multifilament of 33 dtex / 12 filaments. The yarn-making properties in obtaining this multifilament were good, and the measurement results of the obtained multifilament dpf, single fiber sheath thickness, dyed L value, and fastness are shown in Table 1. In Table 1, “o” of fastness means excellent.

(Example 3)
As a sheath component, a modified polyethylene terephthalate (modified PET) having an intrinsic viscosity of 0.58 and a melting point of 234 ° C. copolymerized with 2.3 mol% of 5-sodium sulfoisophthalic acid and 9 mol% of adipic acid in polyethylene terephthalate is used as a core component. , PP, 10% by mass of modified PBT copolymerized with 30% by mole of isophthalic acid in PBT, and 5% by mass of modified polyolefin resin (manufactured by Mitsubishi Chemical Corporation) in which a carboxylic acid ester and an aromatic vinyl compound are graft-polymerized. Using the mixed resin (PP alloy), the core component and the sheath component are respectively supplied to the single screw extruder of each component of the core-sheath compound melt spinning machine, and the extruder temperature is 265 ° C., and the extrusion nozzle temperature is 265 ° C. From the core-sheath composite spinning nozzle having a hole diameter of 0.6 mm and 30 holes, the discharge rate is 28.0 g / min (core component discharge rate 4.8 / Min, discharging the polymer in the sheath component discharge rate 23.2 g / min), to give the winding the undrawn yarn at a winding speed 900 meters / minute. This undrawn yarn was drawn 2.10 times with a heating roller at a temperature of 90 ° C. at a final drawing speed of 400 m / min to obtain a multifilament of 145 dtex / 30 filament. The yarn-making properties in obtaining this multifilament were good, and the measurement results of the obtained multifilament dpf, single fiber sheath thickness, dyed L value, and fastness are shown in Table 1. In Table 1, “o” of fastness means excellent.

(Comparative Example 1)
Polyethylene (PE) is used as the core component, PP is used as the sheath component, the core component and the sheath component are respectively supplied to the single-screw extruder of each component of the core-sheath compound melt spinning machine, and the extruder temperature is extruded at 220 ° C. From the core-sheath composite spinning nozzle having a spinning nozzle temperature of 220 ° C., a hole diameter of 0.6 mm, and a hole number of 24, the discharge rate is 13.6 g / min (core component discharge rate is 3.4 g / min, sheath component discharge rate is 10.2 g / min. ) To discharge the polymer, and an undrawn yarn was obtained at a winding speed of 1000 m / min. This undrawn yarn was drawn 2.45 times with a heating roller at a temperature of 90 ° C. at a final drawing speed of 400 m / min to obtain a multi-filament of 56 dtex / 24 filament. Although the yarn-making property in obtaining this multifilament was good, as with the preparation of the evaluation sample, the multifilament knitted fabric was dyed with a disperse dye, but it was colored with the degree of contamination of the knitted fabric. Was not recognized. Table 1 shows the measurement results of dpf of the obtained multifilament and the sheath thickness of the single fiber.

(Comparative Example 2)
Using the multifilament obtained in Example 3, the knitted fabric of this multifilament was made of Eisen Catillon Marine Blue GPLH (manufactured by Hodogaya Chemical Co., Ltd., blue cationic dye) 2% (vs. fiber). (Mass), atmospheric dyeing was carried out under normal cationic dyeing conditions at a boiling temperature of 30 minutes, but no coloring on the knitted fabric was observed.

(Comparative Example 3)
Undrawn yarn in the same manner as in Example 1 except that the discharge rate in Example 1 was changed to 45.8 g / min (core component discharge rate 3.4 g / min, sheath component discharge rate 42.4 g / min). The undrawn yarn was similarly drawn to obtain a multi-filament of 187 dtex / 24 filament. Although the yarn-making property in obtaining this multifilament is good, as with the preparation of the evaluation sample, when the multifilament knitted fabric is dyed with a disperse dye, the dyed product obtained is satisfactory in light color. The color density was not dyed. Table 1 shows the measurement results of the obtained multifilament dpf, single fiber sheath thickness, dyed L value, and fastness. In Table 1, “x” of fastness means inferior.

(Comparative Example 4)
PP is used for both the core component and the sheath component, the same PP is supplied to the single-screw extruder of each component of the core-sheath compound melt spinning machine, the extruder temperature is set to 220 ° C, the extrusion nozzle temperature is 220 ° C, the hole diameter is The polymer is discharged from a core-sheath composite spinning nozzle with 0.6 mm and 24 holes at a discharge rate of 13.6 g / min (core component discharge rate 3.4 g / min, sheath component discharge rate 10.2 g / min) and wound up An undrawn yarn was wound at a speed of 1000 m / min. This undrawn yarn was drawn 2.45 times with a heating roller at a temperature of 90 ° C. at a final drawing speed of 400 m / min to obtain a multi-filament of 56 dtex / 24 filament. Although the yarn-making property in obtaining this multifilament was good, when the multifilament knitted fabric was dyed with a disperse dye in the same manner as in the preparation of the evaluation sample, the obtained dyed product was extremely pale. The dyeing was not satisfactory in color density. Table 1 shows the measurement results of the obtained multifilament dpf, single fiber sheath thickness, dyed L value, and fastness. In Table 1, “x” of fastness means inferior.

The polypropylene fiber of the present invention can expand the range that can be used from conventional industrial use to apparel use because dyed products with satisfactory concentration and fastness can be obtained by dyeing in the post-processing step. Yes, it is useful and widely usable as a clothing material in the form of yarn or woven or knitted fabric.

Claims (4)

A polypropylene fiber having a core-sheath composite structure and having the following requirements (1) to (4).
(1) Thermoplastic resin whose core part is dispersible dyeable (2) Sheath part is a polypropylene resin (3) Single fiber fineness is 1.5 to 10 dtex
(4) The thickness of the sheath in the fiber cross section is 12 μm or less   The polypropylene fiber according to claim 1, wherein the thermoplastic resin exhibiting disperse dyeability is a polyester resin.   2. The polypropylene fiber according to claim 1, wherein the polypropylene resin is a polypropylene or a mixed resin having a mass ratio of polypropylene to a polyester resin of 99.5 / 0.5 to 90/10.   A woven or knitted fabric comprising the polypropylene fiber according to any one of claims 1 to 3.