JP5299243B2 - Polyester fiber with UV shielding and antibacterial properties - Google Patents

Description

  The present invention relates to a polyester fiber having ultraviolet shielding properties, antibacterial properties, and excellent weather resistance.

  Synthetic fibers are widely used in various fields such as general clothing, interiors, industrial materials, etc. due to various excellent properties including mechanical properties. As a method of imparting a function to a synthetic fiber, a method of adding various functional agents is known, and zinc oxide is known as a functional agent having ultraviolet shielding properties and antibacterial properties.

  As a fiber containing a functional agent, there is known a polyester fiber containing fine particle zinc oxide and fine particle titanium oxide and imparting antibacterial properties using its photoactive point (Patent Document 1). However, the above-described polyester fibers have the disadvantage that fine inorganic particles are likely to aggregate, and not only bleed out during yarn production, but also resin degradation due to photoactivity during ultraviolet irradiation.

  As a method for suppressing aggregation and preventing bleed-out during yarn production, a polyamide fiber using a plasticizer when adding zinc oxide has been proposed (Patent Document 2). However, the method using a plasticizer can be used for a highly hydrophilic polymer composition such as polyamide, but when used for a highly hydrophobic polyester, the excellent mechanical properties, heat resistance, and chemical resistance of the polyester are significantly impaired. Have the disadvantage of being

  Moreover, the method of suppressing aggregation and bleed-out of zinc oxide by making the amount of zinc oxide addition to a polyester fiber small is proposed (patent document 3). However, in order to impart functionality to the fiber, it is necessary to use it together with other functional agents, and due to the photoactive effect of zinc oxide, there is a disadvantage that it is inferior in weather resistance such as causing thermal deterioration during ultraviolet irradiation. It was.

JP 2009-84758 A JP 2002-339163 A Japanese Laid-Open Patent Publication No. 7-189018

  The object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a polyester fiber having ultraviolet shielding properties, antibacterial properties and excellent weather resistance.

  As a result of intensive studies to achieve the above-mentioned object, the present invention results in that titanium oxide having an average particle size of 0.3 to 1.2 μm acts as a zinc oxide dispersant during the production of polyester fibers. We have found that the dispersibility of zinc oxide particles is improved, and as a result, it is possible to obtain polyester fibers having ultraviolet shielding properties, antibacterial properties, and excellent weather resistance by using zinc oxide particles coated with a coupling agent. The present invention has been reached. That is, the gist of the present invention is as follows.

  (1) 0.1 to 4.0% by weight of zinc oxide particles obtained by coating the surface of particles having an average particle size of 0.06 to 1.0 μm with a coupling agent, and an average particle size of 0.3 to 1.2 μm A polyester fiber having ultraviolet shielding properties and antibacterial properties, comprising 0.1 to 3.0% by weight of titanium oxide.

  (2) A woven or knitted fabric using at least a part of the polyester fiber having ultraviolet shielding properties and antibacterial properties according to (1).

  According to the present invention, as described below, an object of the present invention is to provide a polyester fiber having high dispersibility of zinc oxide particles in the polyester fiber and excellent in ultraviolet shielding properties, antibacterial properties, and weather resistance.

  Hereinafter, the present invention will be described in more detail.

  As the zinc oxide contained in the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention, those obtained by coating the particle surface with a coupling agent are applied. Zinc oxide fine particles have antibacterial and antibacterial effects in addition to the effects of ultraviolet absorption and deodorization. However, since they have photocatalytic activity, they cause photodegradation when they are contained in the resin, and the resulting fibers There is a drawback that the physical properties are inferior.

  Therefore, in the present invention, the surface of the particles is coated with a coupling agent in order to suppress the photocatalytic activity, which is a defect of the zinc oxide fine particles, and to have the properties of zinc oxide both optically and chemically. Use the processed one.

  As the coupling agent, a silane coupling agent is preferable, and other coupling agents such as titanium-based, aluminum-based, zirconium-based, and zirco-aluminate-based or silane may be used. Examples of the silane coupling agent include silane coupling agents KBM-403 and KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.

  The method of coating treatment is not particularly limited, but a wet method in which a coupling agent is added while stirring a slurry of zinc oxide powder in water or in a non-aqueous solvent, a Henschel mixer capable of high-speed rotation, a high-speed mixer, etc. Dry method in which zinc oxide powder is sprayed or dropped while stirring at high speed, gas phase method in which coupling agent carried by inert gas such as nitrogen is introduced into reaction vessel containing zinc oxide powder and coated. Etc. can be processed.

  The coating amount of the coupling agent is preferably 0.1 to 20% by weight, although it depends on the surface area of the zinc oxide fine particles. Thus, by covering the surface of the zinc oxide fine particles with the coupling agent, the photocatalytic activity of the zinc oxide fine particles can be sufficiently suppressed without waste with a small amount of coating. Actions such as antibacterial and sterilization can be maintained as they are.

  The content of the zinc oxide particles contained in the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention needs to be 0.1 to 4.0% by weight, preferably 0.2 to 3.0% by weight. %. When the content is less than 0.1% by weight, functions such as ultraviolet shielding and antibacterial properties are not sufficiently imparted. On the other hand, when the content exceeds 4.0% by weight, some of the zinc oxide particles are difficult to be dispersed, the strength of the fiber is reduced, and yarn breakage and fluff are generated due to guide wear during weaving, Operability deteriorates.

  The zinc oxide particles whose surface is coated with the coupling agent contained in the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention must have an average particle size of 0.06 to 1.0 μm, preferably It is 0.07-0.7 micrometer, More preferably, it is 0.08-0.5 micrometer. When the average particle size is less than 0.06 μm, the surface area of the zinc oxide particles is increased, and the amount of the coupling agent coating treatment for sufficiently suppressing the photocatalytic activity is increased. Since the active sites are also covered, not only the antibacterial function can be obtained, but also the aggregation of zinc oxide occurs, which causes deterioration of the yarn production properties such as a decrease in fiber strength and an increase in pressure at the time of discharging molten polymer. On the other hand, when the average particle diameter exceeds 1.0 μm, the surface area of the coated zinc oxide particles becomes small, and the antibacterial function cannot be obtained, and the strength of the fiber is reduced, resulting in guide wear during weaving and the like. Yarn breakage and fluffing occur and operability deteriorates.

  The content of titanium oxide contained in the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention needs to be 0.10 to 3.0% by weight, preferably 0.12 to 2.0% by weight. It is. When the content of titanium oxide is less than 0.10% by weight, the dispersibility of zinc oxide in the polyester fiber becomes low, and functions such as ultraviolet ray shielding and antibacterial properties are not sufficiently imparted. The reason for the low dispersibility of zinc oxide is not clear, but one hypothesis is that titanium oxide, which has high dispersibility in polyester fibers, becomes crystal nuclei and is dispersed in the form of zinc oxide adhering to its periphery. It is possible that Based on this idea, it is possible to increase the dispersibility of zinc oxide in the polyester fiber by using titanium oxide, and it is possible to effectively impart the ultraviolet shielding properties and antibacterial properties that the zinc oxide particles have, It is possible to prevent deterioration of operability due to bleed-out and aggregation of zinc oxide particles during spinning. On the other hand, when the titanium oxide content exceeds 3.0% by weight, the dispersibility of the zinc oxide particles is maintained, but the strength of the fiber is reduced, and yarn breakage and fluff due to guide wear occur during weaving. The operability deteriorates.

  The titanium oxide particles contained in the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention must have an average particle size of 0.30 to 1.2 μm, preferably 0.35 to 1.0 μm, more preferably 0.40 to 0.8 μm. When the average particle diameter of the titanium oxide particles is less than 0.3 μm, aggregation of titanium oxide occurs, and the effect as a dispersant for zinc oxide cannot be obtained. In addition, as the particle size becomes smaller, the photoactivity becomes stronger, and it is activated by irradiating light such as ultraviolet light having energy higher than the band gap of titanium oxide, causing deterioration of the resin, resulting in poor weather resistance. . On the other hand, when the average particle diameter of the titanium oxide particles exceeds 1.2 μm, the fiber strength decreases due to the coarse particles of the titanium oxide, and thread breakage and fluff due to guide wear during weaving and weaving occur, resulting in poor operability. To do.

  The polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention has a strength retention of 70% or more during forced deterioration when irradiated with ultraviolet rays for 6 hours. If the strength retention is less than 70%, it is inferior in weather resistance when irradiated with light of high energy such as ultraviolet rays, and used for applications that require weather resistance such as curtains and industrial materials used outdoors. It becomes difficult to do.

  The polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention has a bactericidal activity value of greater than 0 after 50 washing tests. When the bactericidal activity value is 0 or less, skin resident bacteria and harmful bacteria on the fiber increase, so that it is difficult to use in applications requiring clean and hygienic management such as curtains and sheets used in medical institutions.

  Although the manufacturing method of the polyester fiber which has ultraviolet shielding property and antibacterial property of this invention is not specifically limited, It can manufacture using a melt spinning apparatus by a conventional method. Moreover, the addition of each inorganic particle of zinc oxide and titanium oxide into polyester is a method of preparing a resin composition (master chip) containing these inorganic particles at a high concentration and adding an appropriate amount thereof, or inorganic during polyester polymerization. A method of adding particles in powder form is exemplified and is not particularly limited. However, in order for titanium oxide particles to function effectively as a dispersant for zinc oxide particles, titanium oxide particles are first added to polyester, and then zinc oxide is added. A method of adding particles is preferred.

  The total fineness of the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention is not particularly limited, but is preferably 22 to 250 dtex. In particular, in the case where the thickness is about 84 dtex, the ultraviolet shielding property can be most improved when a low-density woven or knitted fabric is used as a curtain.

  The polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention preferably has a yarn strength of 2.0 to 5.0 cN / dtex and an elongation of 20 to 200%. More preferably, the yarn strength is 2.5 to 5.0 cN / dtex, and the elongation is 20 to 180%. When the yarn strength is less than 2.0 cN / dtex, not only the yarn breakage or fluff due to guide wear or the like occurs during knitting or weaving, but the operability is deteriorated. On the other hand, it is difficult to obtain a fiber having a yarn strength exceeding 5.0 cN / dtex by an ordinary melt spinning method using a single component. If the elongation is less than 20%, it is poor in stability from the viewpoint of stretchability when made into a fabric. On the other hand, fibers with an elongation exceeding 200% tend to cause abnormalities such as dyeing unevenness in a high-order process and are inferior in practicality.

  The cross-sectional form of the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention can be various cross-sectional fibers such as a flat cross section, a multi-leaf cross section, and a hollow cross section in addition to a round cross section.

  The polyester woven or knitted fabric having ultraviolet shielding properties and antibacterial properties of the present invention is obtained by knitting and weaving at least a part of the polyester fibers having ultraviolet shielding properties and antibacterial properties of the present invention. As long as sufficient ultraviolet shielding properties and antibacterial properties are obtained, entangled mixed yarns and twisted yarns with fibers other than the polyester fiber having ultraviolet shielding properties and antibacterial properties of the present invention are produced and knitted and woven. Or those obtained by weaving or knitting fibers other than the polyester fibers having ultraviolet shielding properties and antibacterial properties of the present invention.

Hereinafter, the present invention will be described more specifically based on examples. The measurement and evaluation items in the examples were measured by the methods described below.
-UV shielding property Using a drawn yarn of 84 dtex-36 fil for the warp, using the drawn yarn obtained in the examples and comparative examples for the weft, so that the warp density is 95.0 / inch and the weft density is 93.0 / inch. Fabricate the woven fabric, measure the ultraviolet transmittance in the wavelength range of 0.28 μm to 0.40 μm using a spectrophotometer, and measure the area difference from the measurement sample without blank (blank) as ultraviolet absorptivity (ultraviolet shielding). did. An ultraviolet shielding property of 80% or more was regarded as acceptable.
・ Antibacterial (bactericidal activity value)
After scouring the tubular knitted sample obtained by making the obtained fiber into a tubular knitting using a circular knitting machine, Staphylococcus aureus is used as a test bacterium in accordance with the antibacterial processed fiber product certification standard set by the Japan Fiber Evaluation Technology Council. It is used to measure the bactericidal activity value. The test method was the quantitative test method (bacterial solution absorption method) of JIS L1902 (antibacterial test method for textile products), and the viable cell count method after the culture was performed by the pour plate culture method (colony method).

  The samples were evaluated for untreated (after scouring) and after 50 washing tests. However, the washing method was performed according to the test method of JIS L0217 103, and the detergent was a JAFET standard detergent.

Those with a bactericidal activity value greater than 0 were considered acceptable.
・ Weather resistance Using a UV tester manufactured by Suga Test Instruments Co., Ltd., UV irradiation was performed for 6 hours at a black panel temperature of 83 ± 3 ° C, and the tensile strength of the fiber before and after irradiation was measured with Tensilon. Asked. A strength retention of 70% or more was accepted.

Tensile strength retention = maximum fiber strength after UV irradiation / maximum fiber strength before UV irradiation / dispersibility The cross section of the yarn was observed with a TEM, and the ratio of the number of aggregates of 3.0 μm or more was measured.

◎ ・ ・ ・ less than 0.50% ○ ・ ・ ・ less than 5.0% × ... 5.0% or more (5) Yarn strength Test length 20cm, tensile speed 20cm / min, initial load 1 with Tensilon tensile tester Tensile at / 10 cN / dtex and determined by maximum strength / fineness.

Example 1
A polyethylene terephthalate chip having a melt viscosity of 0.64 to which 10% by weight of zinc oxide has been added is mixed with a polyethylene terephthalate chip having a melt viscosity of 0.64 obtained by adding titanium oxide during polymer polymerization. This was spun by the method and drawn under normal drawing conditions to obtain a polyester fiber having 84 dtex / 36 filaments and an elongation of 40%. Table 1 shows the zinc oxide content, average particle diameter, presence / absence of surface coating with a silane coupling agent, titanium oxide content and average particle diameter of the polyester fiber. Table 1 shows the ultraviolet shielding properties, antibacterial properties, weather resistance, dispersibility, and yarn strength of the polyester fibers. High antibacterial properties, UV shielding properties, weather resistance, dispersibility, and yarn strength were obtained.

Example 2
In Example 1, spinning and stretching were carried out in the same manner except that the content of zinc oxide was 4.0% by weight to obtain a polyester fiber. The dispersibility was at a level where no coarse particles were observed, but no problem, high UV shielding properties, antibacterial properties, and weather resistance were obtained, and the yarn strength was at a level with no problem.

Example 3
In Example 1, spinning and drawing were carried out in the same manner except that the content of zinc oxide was 0.15% by weight to obtain a polyester fiber. The UV shielding property and antibacterial property were at a level with no problem, and high weather resistance, dispersibility, and yarn strength were obtained.

Example 4
In Example 1, spinning and stretching were carried out in the same manner except that the average particle diameter of zinc oxide was changed to 0.10 μm to obtain polyester fibers. High ultraviolet shielding properties were obtained, and antibacterial properties, weather resistance, dispersibility, and yarn strength were at a level with no problem.

Example 5
In Example 1, spinning and stretching were performed in the same manner except that the average particle diameter of zinc oxide was changed to 1.0 μm, and polyester fibers were obtained. The ultraviolet shielding property, antibacterial property, weather resistance, dispersibility, and yarn strength were at a level with no problem.

Examples 6-9
In Example 1, spinning and stretching were carried out in the same manner except that the content of titanium oxide was changed as shown in Table 1, and polyester fibers were obtained. Dispersibility and yarn strength tend to decrease as the content of titanium oxide relative to Example 1 increases, and UV shielding, antibacterial properties, dispersibility, and the content of titanium oxide relative to Example 1 decrease. The yarn strength tended to decrease, but all were at a satisfactory level.

Examples 10-15
In Example 1, spinning and stretching were carried out in the same manner except that the average particle diameter of titanium oxide was changed as shown in Table 1, and polyester fibers were obtained. As the average particle size of the titanium oxide compared to Example 1 was increased, the dispersibility of zinc oxide was lowered, and the ultraviolet shielding property, antibacterial property, and yarn strength tended to decrease. Moreover, since the average particle diameter of the titanium oxide compared with Example 1 became small, dispersibility became low in both zinc oxide and titanium oxide, and the ultraviolet shielding property, antibacterial property, weather resistance, and yarn strength tended to decrease. However, none of them was a problem level.

Comparative Example 1
In Example 1, spinning and drawing were carried out in the same manner except that the content of zinc oxide was 5.0% by weight to obtain a polyester fiber. High UV shielding properties and antibacterial properties were obtained, and weather resistance was at a level that was not a problem, but dispersibility and yarn strength were low, and operability was unstable.

Comparative Example 2
In Example 1, spinning and stretching were carried out in the same manner except that the content of zinc oxide was 0.08% by weight to obtain a polyester fiber. High weather resistance, dispersibility, and yarn strength were obtained, but UV shielding properties and antibacterial properties were insufficient.

Comparative Example 3
In Example 1, spinning and drawing were performed in the same manner except that the average particle diameter of zinc oxide was 0.03 μm, and polyester fibers were obtained. The ultraviolet shielding property and weather resistance were at a level with no problem, but the antibacterial property was insufficient, the dispersibility and the yarn strength were low, and the operability was unstable.

Comparative Example 4
In Example 1, spinning and stretching were carried out in the same manner except that the average particle diameter of zinc oxide was 1.30 μm, and polyester fibers were obtained. The ultraviolet shielding property and weather resistance were at a level with no problem, but the yarn strength was low and the operability was unstable, and the antibacterial property and dispersibility were insufficient.

Comparative Example 5
In Example 1, spinning and drawing were carried out in the same manner except that the surface coating with a silane coupling agent of zinc oxide was not carried out to obtain a polyester fiber. The ultraviolet shielding property, antibacterial property, dispersibility, and yarn strength were at a level that was not a problem, but the strength was greatly deteriorated during ultraviolet irradiation, and the weather resistance was insufficient.

Comparative Example 6
In Example 1, spinning and drawing were carried out in the same manner except that the content of titanium oxide was 4.0% by weight to obtain a polyester fiber. High UV shielding properties, antibacterial properties, weather resistance, and dispersibility were obtained, but yarn strength was low and operability was unstable.

Comparative Example 7
In Example 1, spinning and stretching were carried out in the same manner except that the content of titanium oxide was 0.05% by weight to obtain a polyester fiber. Although the weather resistance was at a level with no problem, the yarn strength was low and the operability was unstable, and the ultraviolet shielding property, antibacterial property and dispersibility were insufficient.

Comparative Example 8
In Example 1, spinning and stretching were carried out in the same manner except that the average particle diameter of titanium oxide was 2.0 μm to obtain a polyester fiber. Although high weather resistance was obtained and ultraviolet shielding properties and antibacterial properties were at a level that was not a problem, dispersibility and yarn strength were low and operability was unstable.

Comparative Example 9
In Example 1, spinning and stretching were carried out in the same manner except that the average particle diameter of titanium oxide was 0.20 μm to obtain a polyester fiber. The yarn strength was low and the operability was unstable, and the ultraviolet shielding properties, antibacterial properties, weather resistance, and dispersibility were insufficient.

Comparative Example 10
In Example 1, spinning and stretching were carried out in the same manner except that the master chip to which zinc oxide was added was not mixed to obtain a polyester fiber. High weather resistance, dispersibility, and yarn strength were obtained, but UV shielding properties and antibacterial properties were insufficient.

Comparative Example 11
In Example 1, spinning and stretching were carried out in the same manner except that no titanium oxide was added to the base chip to obtain a polyester fiber. Although the weather resistance was at a level with no problem, the yarn strength was low and the operability was unstable, and the ultraviolet shielding property, antibacterial property and dispersibility were insufficient.

Claims (2)

0.1 to 4.0 wt% of zinc oxide particles obtained by coating the surface of particles having an average particle size of 0.06 to 1.0 μm with a coupling agent, and titanium oxide having an average particle size of 0.3 to 1.2 μm A polyester fiber having ultraviolet shielding properties and antibacterial properties, characterized by containing .1 to 3.0% by weight. A woven or knitted fabric using at least a part of the polyester fiber having ultraviolet shielding properties and antibacterial properties according to claim 1.