JP2008223172A - Stainproof spun-dyed fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a stainproof spun-dyed fiber that is sufficiently usable for industrial materials such as material of construction, building material, etc., without any need of dyeing and stainproof processing and has a high strength and stain resistance. <P>SOLUTION: The stainproof spun-dyed fiber is a core-sheath type conjugate fiber comprising a core component composed of a polyethylene terephthalate containing a colored pigment and a sheath component composed of a polyethylene terephthalate containing a benzoxazole-based fluorescent brightener and having a core sheath mass ratio (core: sheath) of 1:1-5:1 and a strength at break of ≥5.5 cN/dtex. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an antifouling primary fiber suitable for use in civil engineering sheets and various nets used for civil engineering and construction materials.

  Conventionally, various types of processing have been performed to impart antifouling properties to some civil engineering sheets and various nets used for civil engineering and construction materials. For example, water-absorbing SR processing by hydrophilic processing that makes it easy to remove dirt in washing, SG processing that applies a fluorine processing agent and coating processing to make dirt difficult to adhere, or both SR processing and SG processing characteristics Combined SGR processing is common.

  However, since such processing has a high processing cost and does not have a continuous antifouling effect, as an attempt to impart antifouling properties to the fiber itself, Patent Document 1 discloses that benzoxazole-based fluorescent light is produced during the production of polyester fibers. An antifouling polyester synthetic fiber containing 0.01 to 0.3% by weight of a whitening agent has also been proposed.

The fiber proposed in Patent Document 1 is conscious of a white fabric mainly used for clothing. However, in recent years, civil engineering sheets and nets used for civil engineering and construction materials are commonly used in black or green colors. And since civil engineering sheets and nets are large-sized, large dyeing and antifouling processing facilities are required, resulting in high processing costs. Therefore, there is no need to perform dyeing or antifouling after the product is produced, and there is an increasing demand for antifouling primary fibers that are colored in a fiber state and imparted with antifouling properties.
Japanese Patent No. 2763940

  The present invention solves the above-mentioned problems and does not require dyeing or antifouling after making the product, and can be used sufficiently for industrial materials such as civil engineering materials and building materials, and has high strength and antifouling properties. It is a technical problem to provide antifouling raw fiber.

  The inventors of the present invention have arrived at the present invention as a result of studies to solve the above problems.

  That is, the present invention is a core-sheath type composite fiber in which the core component is composed of polyethylene terephthalate containing a color pigment, and the sheath component is polyethylene terephthalate containing a benzoxazole-based fluorescent whitening agent. The gist of the antifouling fiber is characterized in that the core (sheath) is 1: 1 to 5: 1 and the cutting strength is 5.5 cN / dtex or more.

  The antifouling primary fiber of the present invention is a core-sheath type composite fiber, colored by adding a coloring pigment to the core component, and containing a benzoxazole-based fluorescent whitening agent in the sheath component. Since antifouling property is imparted, there is no need to perform dyeing or antifouling processing by post-processing, which is advantageous in terms of cost. And since it consists of polyethylene terephthalate, its cutting strength is high, and it can be used for industrial materials such as civil engineering materials and building materials.

  Hereinafter, the present invention will be described in detail.

  Since the antifouling fiber according to the present invention is used for antifouling civil engineering sheets and nets used for civil engineering and construction materials, it is necessary that coloring and antifouling properties be imparted. It exhibits a core-sheath structure comprising a core component containing a color pigment and a sheath component containing a benzoxazole-based fluorescent brightener as an antifouling agent.

  The core component is mainly composed of polyethylene terephthalate (hereinafter referred to as PET) which is excellent in dimensional stability and weather resistance, and is inexpensive and versatile. The intrinsic viscosity [η] of the core component PET is preferably 0.8 to 1.1. When the intrinsic viscosity [η] is lower than 0.8, it is difficult to obtain high-strength fibers. When the intrinsic viscosity [η] is higher than 1.1, the stretchability is deteriorated and the cost is disadvantageous.

  In order not to require dyeing, the core component PET must contain a color pigment. Examples of the color pigment include inorganic pigments such as carbon black, titanium oxide, zinc oxide, chromium oxide and iron oxide, and organic pigments such as phthalocyanine, azo, perinone, perylene, and anthraquinone.

  As a method of incorporating a color pigment into PET, a master chip in which 20 to 30% by mass of a color pigment is kneaded into the same PET as the core component is prepared, so that it can have an arbitrary concentration with PET used for the core component during spinning. A method of dry blending and kneading using a measuring mixer or the like is preferable.

  The content of the color pigment in the core component (content in the core component) is preferably 0.3 to 1.0% by mass, and if the content concentration is less than 0.3% by mass, the color becomes dull. If it exceeds mass%, the stretchability becomes inferior and the strength becomes inferior.

  In addition to the color pigment, the core component may contain or copolymerize various additives and a third component to the extent that the original performance is not impaired.

  Next, the sheath component has PET as a main component in the same manner as the core component. The intrinsic viscosity [η] is preferably 0.8 to 1.1 as in the core component. When the intrinsic viscosity [η] is lower than 0.8, it is difficult to obtain a high-strength fiber. Becomes inferior, and it is disadvantageous in terms of cost.

  The sheath component needs to contain a benzoxazole fluorescent whitening agent in order to impart antifouling properties. As the benzoxazole-based fluorescent whitening agent, Hostalux KS manufactured by Clearant or East Bright Optical Brightener OB-1 manufactured by Eastman Chemical Japan can be used.

  In addition, the content of the benzoxazole fluorescent whitening agent in the sheath component (content in the sheath component) is preferably 0.1 to 0.5% by mass, and if the content is less than this range, the antifouling property is inferior, Exceeding this is not preferable because the sheath component is yellowed, so that the original coloration by the color pigment contained in the core component cannot be obtained, and the cost is disadvantageous.

  In addition, the method of kneading the benzoxazole-based fluorescent whitening agent into the sheath component can be dry blended with the sheath component PET in a powder state, but in order to knead to a uniform concentration, It is preferable to form a master chip as in the case of adding a color pigment.

  The sheath component may be copolymerized with a minute amount of a color pigment, various additives, and further a third component as long as the original performance is not impaired.

  The reason why the antifouling raw fiber of the present invention has a core-sheath structure is as follows. When a single type of fiber is combined with a color pigment necessary for obtaining an original color and a benzoxazole fluorescent whitening agent necessary for obtaining an antifouling effect, the antifouling effect is reduced. As a factor, it is presumed that the antifouling effect by the benzoxazole fluorescent whitening agent is hindered by the color pigment because the color pigment and the benzoxazole fluorescent whitening agent are mixed on the fiber surface.

  Next, the core-sheath composite ratio of the antifouling primary fiber of the present invention is 1: 1 to 5: 1, and preferably 2: 1 to 4: 1. When the core component is larger than this range, the composite form tends to be nonuniform between the single yarns, and the drawability becomes poor. On the other hand, when the core component is smaller than this range, coloring with the coloring pigment becomes insufficient.

  Furthermore, the cutting strength of the antifouling primary fiber according to the present invention is 5.5 cN / dtex or more, and preferably about 6.0 to 7.5 cN / dtex. When the cutting strength is less than 5.5 cN / dtex, the use is limited for use for industrial materials.

  In order to make the antifouling primary fiber of the present invention have such a strength, it is possible to adopt a manufacturing method as described below. In consideration of stretchability, the cutting strength is preferably 7.5 cN / dtex or less.

  Since the antifouling primary fiber of the present invention is mainly used for civil engineering and construction materials, the total fineness is preferably 500 to 2000 dtex, and the single yarn fineness is 5 to 30 dtex, which provides good stretchability. Is preferred. The cross-sectional shape of the fiber may be irregular for both the core and the sheath. However, it is preferable that the fiber has a circular cross-sectional shape and the core and the sheath are concentric as having excellent stretchability and high strength.

  Next, the manufacturing method of the antifouling original fiber of the present invention will be described. First, chips of a core component and a sheath component are supplied, and melt spinning is performed using a conventional compound spinning device. A two-step method in which the undrawn yarn is wound once and then drawn may be used, but the spin draw method in which drawing is performed continuously without winding is preferable in terms of productivity and cost. As the stretching method, a roller stretching performed using a heating roller or a method performed by providing a steam heat treatment apparatus between the rollers can be employed. The winding speed is preferably about 2000 to 4000 m / min. If the winding speed is slower than this range, the productivity is inferior, and if it is faster, high strength is difficult to obtain or the stretchability is inferior.

Next, the present invention will be specifically described with reference to examples. In addition, each physical-property value in an Example was measured with the following method.
(A) Intrinsic Viscosity of Polyester Measured at a concentration of 0.5 g / dl and a temperature of 20 ° C. using a mixture of equal mass of phenol and ethane tetrachloride as a solvent.
(B) Cutting strength, elongation According to the standard time test of tensile strength and elongation rate of JISL-1013, it was measured using a Shimadzu Autograph DSS-500 at a grip interval of 25 cm and a pulling speed of 30 cm / min.
(C) Evaluation of antifouling property In accordance with JISL-1919: 2006, artificial pollutants were subjected to the A-2 method stain resistance test using powder pollutant-2, visually determined and compared and evaluated by the following methods. . In addition, the test piece used what knitted the fiber, washed the water of the cylinder knitted fabric of length 8cm once with a washing machine without using detergent, removed the oil agent, and air-dried.
○: Little stain Δ: Slightly stain ×: Large amount of stain (d) Fiber color The fiber was knitted and visually evaluated for color shading.
○ ・ ・ ・ Dark × ・ ・ ・ Light

Example 1
Contains a core chip containing PET with an intrinsic viscosity [η] of 1.0, and a master chip containing 20% by mass of titanium oxide as a coloring pigment in PET with an intrinsic viscosity [η] of 0.7. The mixture was dry blended with a metering mixer so that the amount was 0.5% by mass.
Next, PET with intrinsic viscosity [η] 1.0 as the sheath component, PET with intrinsic viscosity [η] 0.7, and “East Bright” Optical Brightener OB-1 manufactured by Eastman Chemical Japan Co., Ltd. as the fluorescent whitening agent. The master chip kneaded with 20% by mass was dry blended with a measuring mixer so that the content of the optical brightener in the sheath component was 0.2% by mass.
A core-sheath type composite spinneret having a hole diameter of 0.5 mm and 96 holes was attached to a conventional composite melt spinning apparatus, and spinning was performed at a base temperature of 300 ° C. and a core-sheath mass ratio of 2: 1. After passing through a heating cylinder having a temperature of 400 ° C. and a length of 30 cm provided just below the spinneret, the product was cooled by a cooling fan having a temperature of 15 ° C. and a speed of 0.6 m / sec. Subsequently, an oil agent is applied and taken up by a non-heated first roller, followed by 1.01 time alignment by a non-heated second roller, and then steam at a temperature of 400 ° C. and a pressure of 0.6 MPa is applied to the yarn. Then, the film was stretched 5.1 times with a third roller having a surface temperature of 200 ° C. After that, 2% relaxation heat treatment was performed with a fourth roller having a surface temperature of 140 ° C., wound around a winder with a speed of 3000 m / min, and a circular cross-sectional shape (core and sheath were concentrically arranged) 1110 dtex / 96 filament An antifouling fiber was obtained.

Example 2
The same procedure as in Example 1 was performed except that the color pigment contained in the core component was changed to carbon black.

Example 3
It carried out like Example 1 except having changed content of the fluorescent whitening agent in a sheath component into 0.4 mass%.

Example 4
The same procedure as in Example 1 was performed except that the core-sheath mass ratio was changed to 4: 1.

Comparative Example 1
The same procedure as in Example 1 was performed except that the core-sheath mass ratio was changed to 1: 2.

Comparative Example 2
The same procedure as in Example 1 was performed except that the core-sheath mass ratio was changed to 7: 1.

Comparative Example 3
A single-type melt spinneret is mounted on a conventional melt spinning apparatus, PET having an intrinsic viscosity [η] of 1.0, 0.5% by mass of titanium oxide as a color pigment, and an example as a benzoxazole-based fluorescent brightening agent The same procedure as in Example 1 was performed except that 0.2% by mass of the same as in No. 1 was contained to obtain a single type of fiber.

Comparative Example 4
The same procedure as in Comparative Example 3 was performed except that the color pigment was changed to carbon black.

Comparative Example 5
The same operation as in Comparative Example 3 was conducted except that only the color pigment (titanium oxide) was contained in the fiber.

Comparative Example 6
The same operation as in Comparative Example 4 was conducted except that only the color pigment (carbon black) was contained in the fiber.

  Table 1 shows the evaluation results of the physical properties and antifouling properties of the fibers obtained in Examples 1 to 4 and Comparative Examples 1 to 6.

As is apparent from Table 1, the fibers obtained in Examples 1 to 4 were able to be obtained with good stretchability, high cutting strength, and excellent antifouling properties and color. On the other hand, since the fiber obtained in Comparative Example 1 has a small ratio of the core component containing the color pigment, the use of the light color is limited. Further, in Comparative Example 2, since the ratio of the sheath component was reduced, a uniform composite form could not be obtained, and yarn breakage occurred frequently at the time of drawing, and fibers could not be obtained. Since the fibers obtained in Comparative Examples 3 to 4 were single-type fibers, the fibers obtained in Comparative Examples 5 to 6 were single-type fibers and contained a benzoxazole-based fluorescent whitening agent. None of them were inferior in antifouling property.

Claims (1)

The core component is a core-sheath type composite fiber composed of polyethylene terephthalate containing a color pigment, and the sheath component is polyethylene terephthalate containing a benzoxazole-based fluorescent whitening agent, and the core-sheath mass ratio (core: sheath) is 1. : 1-5: 1, antifouling raw fiber characterized by having a cutting strength of 5.5 cN / dtex or more.