JP2008266873A - Polyester monofilament and woven fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester monofilament excellent in abrasion resistance, having small variation of monofilament diameter and good surface smoothness and having tensile strength which is necessary and sufficient as an industrial woven fabric and provides an industrial woven fabric which used the monofilament. <P>SOLUTION: The polyester monofilament is composed of a resin composition containing inorganic particles having 0.2-1.0 μm average particle diameter and ≤2.5 ratio of particle size distribution represented by d25/d75 in an amount of 1-15 wt.% based on polyester-based resin. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to polyester monofilaments and industrial fabrics. More specifically, the present invention relates to a polyester monofilament having excellent abrasion resistance, small wire diameter variation, good surface smoothness, and sufficient and sufficient tensile strength as an industrial fabric, and an industrial fabric using the same. is there.

  In general, fibers represented by monofilaments made of polyester, such as polyethylene terephthalate, have excellent mechanical properties, heat resistance, etc., and thus have been conventionally used in various industrial parts, clothing and industrial fiber materials, various fabrics, etc. Has been used.

  Specific examples of these fabrics include papermaking fabrics, filter fabrics, and other uses such as various brushes, writing brushes, printing screen rods, fishing lines, and rubber reinforcing fiber materials. ing.

  Among them, as a constituent material in the papermaking industry, such as papermaking wire (textile for lifting paper), papermaking dryer canvas (textile for paper drying process) and papermaking press felt (textile for paper squeezing process), polyester is used. Monofilaments are widely used.

  However, in these industrial applications, when the polyester monofilament is used for contact with other substances such as particles, structures such as metals, ceramics, and plastics, the polyester monofilaments are abraded by these particles or structures. Since they are easily damaged, nets and fabrics made of polyester monofilaments have the drawback of having a short product life.

  For example, in the paper manufacturing industry, acid paper has been mainly produced in the past. However, as the problem of aging deterioration of paper becomes more prominent, conversion to neutral paper has been actively performed. . Along with the conversion from acid paper to neutral paper, the filler for paper called filler was changed from talc to calcium carbonate, but the calcium carbonate particles are harder than talc particles, so they are used in the papermaking process. In particular, the paper making wire made of polyester monofilament has a drawback that its life is shorter than that of polyamide monofilament paper making wire such as nylon 6.

  However, although the papermaking wire made of nylon has the advantage that it is relatively hard to wear as described above, it has a fatal defect that the size of the papermaking wire changes due to moisture at the time of papermaking, causing trouble in papermaking. Therefore, it has been desired to improve the wear resistance of polyester monofilament papermaking wire having good dimensional stability even during papermaking.

  Also, in the field of papermaking dryer canvas, the problem of abrasion of polyester monofilament on the surface that comes into contact with filler-containing paper has been pointed out, and in particular, paints containing inorganic pigments such as dry powder calcium carbonate and kaolin are coated and dried. The polyester monofilament constituting the dryer canvas used in the process has been required to be improved because of its remarkable wear.

  In view of this situation, many attempts have been made to improve the abrasion resistance of polyester monofilaments.

  For example, a paper fabric (for example, see Patent Document 1) having improved wear resistance using a monofilament containing polyethylene terephthalate and thermoplastic polyurethane, which is a thermoplastic elastomer, has been proposed. Since the thermoplastic polyurethane resin used causes thermal decomposition of urethane bonds and ether chains at the melt spinning temperature of polyethylene terephthalate, the resulting monofilaments did not have sufficient tensile strength for industrial use.

  In addition, a non-lamellar platelet having a thickness of 20 to 100 nm and an aspect ratio of 20: 1 or less selected from the group consisting of inorganic oxide, hydroxide, carbonate, bicarbonate, nitride and carbide in polyester. Technology for improving the abrasion resistance of polyester fibers by blending shaped particles (for example, see Patent Document 2), or oxidation of silicon, aluminum and / or titanium with polyester having a hydrolysis stabilizer and an average particle size of 100 nm or less Although the technique (for example, refer patent document 3) which improves the abrasion resistance of industrial cloth by mix | blending a thing is proposed, although these polyester fibers have sufficient tensile strength for industrial use, Since the diameter of the non-lamellar platelet-shaped particles is small, sufficient abrasion resistance cannot be obtained, and it is not practical for industrial textiles.

  Further, a technique for suppressing white powder scum mainly composed of fiber shavings in the weaving process of polyester monofilament for screen wrinkles by blending a calcium compound (for example, see Patent Document 4), for papermaking by blending calcium carbonate Techniques for improving the abrasion resistance of polyphenylene sulfide monofilaments used in industrial fabrics such as dryer canvas (see, for example, Patent Document 5) have been proposed, but these fibers control the particle size distribution of the added particles. Therefore, the wear resistance could not be improved, and the latter also had a different composition.

In addition, a polyester composition capable of producing a fiber having excellent abrasion resistance obtained by adding zirconium oxide particles to an aromatic polyester obtained by copolymerizing a compound having at least one sulfonic acid group or sulfonic acid metal base (for example, The monofilament obtained from this composition has a slight wear resistance improving effect, but the added zirconium particles are agglomerated due to agglomeration. Due to the large fluctuation, the surface smoothness required for industrial fabrics could not be obtained.
Japanese Patent Laid-Open No. 2-80688 JP 2007-23474 A JP 2006-63511 A JP-A 63-262290 JP 2001-254227 A JP-A-5-171014

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue.

  Accordingly, an object of the present invention is to provide a polyester monofilament having excellent wear resistance, small wire diameter fluctuation, good surface smoothness, and necessary and sufficient tensile strength as an industrial fabric, and an industrial product using the same. To provide a woven fabric.

  To achieve the above object, according to the present invention, the polyester resin has an average particle size of 0.2 to 1.0 μm and d25 / d75 (d25: large particle size in a volume-based cumulative distribution of particles). Particle size at 25% of the total volume from the side d75: Inorganic particles having a particle size distribution ratio expressed by a volume-based cumulative distribution of particles of 75% of the total volume from the large particle size side) of 2.5 or less A polyester monofilament comprising a resin composition containing 1 to 15% by weight is provided.

In the polyester monofilament of the present invention,
The monofilament has a wire diameter of 0.1 mm to 2.0 mm,
The inorganic particles are at least one selected from calcium carbonate, titanium dioxide and silicon dioxide;
The polyester resin is mainly composed of at least one selected from polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate;
The polyester resin is polyethylene terephthalate, and the carboxyl terminal concentration is 10 equivalents / ton or less;
The filament diameter variation rate of the monofilament is 4.0 or less, and the tensile strength of the monofilament measured in accordance with JIS L-1013: 1999-8.5 is 2.0 cN / dtex or more, and The dry powder calcium carbonate wear rupture number measured by the method shown below for monofilament is preferably 200 times or more / reciprocation, and a preferable condition is obtained by satisfying this condition. be able to.

  The woven fabric of the present invention is characterized by using the above-mentioned polyester monofilament as at least a part of warp and / or weft, and exhibits an excellent wear resistance effect in industrial fabrics, particularly paper fabrics.

  According to the present invention, as described below, the wear resistance is superior to that of the conventional one, the wire diameter variation is small, the surface smoothness is good, and the necessary and sufficient tensile strength as an industrial fabric is obtained. Polyester monofilaments suitable as a constituent material for industrial fabrics, particularly papermaking fabrics, and industrial fabrics using the same can be obtained.

  The present invention is described in detail below.

  The polyester resin constituting the polyester monofilament in the present invention is a polyester resin synthesized from a dicarboxylic acid or ester-forming derivative such as polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate and a diol or ester-forming derivative.

  Specific examples of the inorganic particles used in the present invention include calcium carbonate, titanium dioxide and silicon dioxide, silicon nitride, clay, talc, kaolin, zirconium acid, carbon black and the like. Calcium, titanium dioxide and silicon dioxide provide excellent dry powder calcium carbonate wear resistance, with calcium carbonate being particularly preferred.

  In this invention, it is preferable that content of the inorganic particle contained in a polyester monofilament is 1 to 15 weight% with respect to a polyester-type resin, More preferably, it is 5 to 10 weight%. If the content is less than 1% by weight, the wear resistance is insufficient, and if it exceeds 15% by weight, not only will the operation become unstable, such as the occurrence of stretch breaks during the production of the monofilament, but the tensile strength of the monofilament Is unfavorable because it decreases.

  The average particle size of the inorganic particles used in the present invention needs to be 0.2 to 1.0 μm, and the inorganic particles used in the present invention have a particle size distribution ratio of 2.5 or less as described above. It is necessary to be. The particle size distribution ratio is an index greater than 1 representing the sharpness of the particle size distribution, and the closer the value is to 1, the sharper the distribution.

  Wear caused by fillers and inorganic pigments in a papermaking fabric, which is a preferred application of the present invention, is intense wear that wears away the fibers constituting the fabric, not just damage of the surface of the fabric. The present inventors have discovered that the average particle size and the particle size distribution ratio described above are essential in order to greatly reduce such wear. That is, such intense wear is a phenomenon in which fillers and inorganic pigments scrub the fiber surface, but microscopically, the filler and inorganic pigment particles compress the fiber surface layer, and the fiber surface layer is attacked by attacks such as compression, cutting, and striking. As a result, the following improvement technology was found to be effective.

  First, by mixing inorganic particles in the fiber, the inorganic particles present on the fiber surface layer are directly attacked by fillers and inorganic pigments to suppress the destruction of the fiber substrate, and second, the inorganic particles are excessive. If the particle size is too large, the inorganic particles are easily destroyed by the attack of the filler or inorganic pigment, and the wear resistance is not effective, and there is an upper limit size that can withstand the attack of the filler or pigment particles. When the particles are excessively small, the fiber substrate cannot be protected from the attack of the filler or inorganic pigment, the wear resistance is not effective, and there is a lower limit size that can withstand the attack of the filler or pigment particles.

  The above average particle diameter and particle size distribution ratio are critical values determined based on the above experiments and considerations.

  Moreover, the average particle diameter of the inorganic particles used in the present invention is preferably 0.3 to 0.7 μm. In order to provide excellent wear resistance, a certain degree of particle size is necessary as described above, and conversely, if it is too large, coarse protrusions are generated on the monofilament, which is important for industrial textile applications. The rate of fluctuation of the monofilament's wire diameter increases, which not only lowers the surface smoothness of the fabric but also reduces the wear resistance.

  The particle size distribution ratio of the inorganic particles used in the present invention is preferably 2.0 or less. By setting the particle size distribution ratio to 2.0 or less, it is difficult to form coarse protrusions when monofilaments are formed, and there are fewer cases of dropping off. In addition, the monofilament diameter fluctuation rate, which is particularly important in industrial textile applications, is reduced, and the surface smoothness of the textile can be improved. The particle size distribution ratio is particularly preferably 1.7 or less.

  In addition, the inorganic particles used in the present invention may use a dispersant or a surface treatment agent in order to control cohesion or improve the affinity with polyester. Examples of such dispersants or surface treatment agents include silane coupling agents, titanium coupling agents, esters such as carboxylic acid, phosphoric acid, and sulfonic acid or metal salts thereof, or polyacrylic acid and derivatives thereof and metal salts thereof. Etc. Of these, polyacrylic acid or a copolymer of polyacrylic acid and a derivative thereof and a metal salt thereof are particularly preferable.

  The polyester monofilament of the present invention has a dry powder calcium carbonate abrasion breakage measured by the above method of 200 times or more / reciprocation, and the outstanding abrasion resistance effect in the papermaking dryer canvas in which the abrasion due to the dry powder calcium carbonate is extremely remarkable. It is preferable from exhibiting.

  Moreover, although the tensile strength which the polyester monofilament of this invention requires changes with uses, it is preferable that it is generally 2.0 cN / dtex or more. If the tensile strength is less than 2.0 cN / dtex, the necessary minimum strength of the industrial fabric may not be maintained, and it may be difficult to develop the industrial fabric.

  The polyester monofilament of the present invention can satisfy the above-mentioned conditions and further apply appropriate yarn-making conditions, so that the variation rate of the wire diameter can be lowered to 3.0% or less, which is required when making a woven fabric. It can exhibit excellent surface smoothness. Here, when the variation rate of the wire diameter exceeds 3.0%, the surface smoothness of the woven fabric is deteriorated, and unevenness is likely to occur on the paper surface. The wire diameter variation rate is more preferably 2.5% or less, and particularly preferably 2.0% or less.

  The polyester monofilament of the present invention is a single continuous yarn, and the cross-sectional shape perpendicular to the fiber axis direction (hereinafter referred to as cross-sectional shape or cross-section) is round, elliptical, triangular, T, Y, H, It may have any cross-sectional shape such as +, 5 leaves, 6 leaves, 7 leaves, 8 leaves, etc., squares, rectangles, rhombuses, dogbones, and saddles.

  Among these cross-sectional shapes, a round cross-section is preferable from the viewpoint of wear resistance, posture stability, and smoothness.

  The polyester monofilament of the present invention can be produced, for example, as follows, but is not limited thereto.

  First, if necessary, the dried thermoplastic resin pellets and inorganic particles are preliminarily weighed and mixed, or mixed while being weighed and supplied to a single-screw extruder or a twin-screw extruder, and the melting point of the polyester resin used. After melt-kneading at a temperature 20 to 60 ° C. higher than that, extruded from the nozzle at the end of the extruder, guided to a cooling water tank, cut the gut cooled, and polyester resin pellets containing a predetermined amount of inorganic particles (hereinafter, preliminary kneading) Pellets).

  In this case, the content of inorganic particles in the polyester-based resin is set to a concentration desired to be contained in the monofilament, or a master batch set to be higher than the concentration desired to be contained in the monofilament.

  In the case of the pre-kneaded pellets thus obtained, the pellets are supplied to an extruder spinning machine having a metering gear pump and a spin block at the tip, and at a temperature 20 to 60 ° C. higher than the melting point of the polyester resin used. After melt-kneading, spinning from the spinneret. Next, after the molten spun yarn is introduced into a cooling water bath and cooled and solidified, it is stretched in the first and second stretching zones without being wound, and then heat-set in the heat-setting zone, and then as necessary. A desired polyester monofilament can be obtained by applying an oil agent and winding it around a bobbin. A stationary kneading element (streamline changer) can also be used in combination.

  As another method, when using a high-concentration masterbatch or inorganic particles, each of the thermoplastic resin pellets is preliminarily metered and mixed so as to have a predetermined amount of inorganic particle content, or each metered and mixed, It is supplied to an extruder type spinning machine having a measuring gear pump and a spin block at the tip, melted and kneaded at a temperature 20 to 60 ° C. higher than the melting point of the used thermoplastic resin, and then spun from the spinneret. Next, after the molten spun yarn is introduced into a cooling water bath and cooled and solidified, it is stretched in the first and second stretching zones without being wound, and then heat-set in the heat-setting zone, and then as necessary. The target polyester monofilament can also be obtained by applying an oil agent and winding it around a bobbin. A stationary kneading element (streamline changer) can also be used in combination.

  In order to make the wire diameter fluctuation rate of the monofilament 4.0 or less, the distance from the die to the cooling water tank is 10 cm or less, in addition to setting the average particle size and the particle size distribution ratio of the inorganic particles of the present invention within the scope of the present invention. It is preferable to set it as 7 cm or less. The lower limit is 1 cm. This distance is about 15 to 30 cm in the case of normal cooling, but in the case of the monofilament of the present invention in which inorganic particles are blended, instability of the melt deformation process can be eliminated by setting the above range.

  The industrial fabric of the present invention is one in which the above-described polyester monofilament of the present invention is used for at least a part of warp and / or weft. The polyester monofilament of the present invention is a continuous yarn composed of one single yarn. In addition to being used as a single yarn, a combination of a plurality of continuous yarns composed of this single yarn, and a twisted combination of a plurality of single yarns, etc. It may be used as at least a part of the weft.

  The weaving method of the industrial fabric can be appropriately selected depending on the application. For example, a known weaving method such as plain weaving, twill weaving, double weaving, and triple weaving can be employed.

  Applications of the industrial fabrics of the present invention include paper fabrics that make use of their excellent wear resistance, surface smoothness and tensile strength, especially papermaking wires, papermaking dryer canvases and papermaking press felts, among others. When applied to a paper-making dryer canvas that is greatly affected by dry powdered calcium carbonate, it can exhibit an excellent wear resistance effect.

  Hereinafter, the polyester monofilament of the present invention will be described in more detail based on examples.

  The average particle size and particle size distribution of the inorganic particles, the variation rate of the diameter of the polyester monofilament, the tensile strength, the spinning operability, and the dry powder calcium carbonate abrasion breakage were evaluated by the following methods.

[Average particle size and particle size distribution]
In the case of raw material particles, an ethylene glycol dispersion is diluted with water. In the case of particles in fibers, a particle dispersion in which fibers are dissolved in orthochlorophenol is prepared, and a laser diffraction scattering type particle size distribution analyzer (LA700 manufactured by Horiba Ltd.) is prepared. ) Was used to measure the average particle size and particle size distribution. For the particle size distribution, the water dilution concentration is adjusted so that the light transmittance is 80 to 95%, and the particle diameter of the integrated volume fraction of 50% in the equivalent spherical distribution measured at a measurement temperature of 25 ° C. and a circulation rate of 570 ml / min. The aggregated particle diameter (= average particle diameter) was set, and the particle diameters of 25% and 75% from the large particle diameter side were d25 and d75, respectively.

[Tensile strength]
According to JIS L-1013: 1999-8.5 tensile strength and elongation, the measurement was performed under the conditions of a test length of 250 mm and a tensile speed of 300 mm / min. The tensile strength is a value obtained by converting the measured sample fineness per decitex unit. For the measurement, a tensile tester (Tensilon / UTM-ll-100 manufactured by Orientec Co., Ltd.) was used.

[Wire diameter fluctuation rate]
Using an outer diameter measuring machine according to Anritsu laser outer diameter measuring machine KG601A, the outer diameter was measured under the conditions of a measuring speed of 15 m / min, a measuring interval of 0.1 sec / time, and a measuring point of 1024 times. Using a data processor according to NR-250 & PC manufactured by the manufacturer, the wire diameter variation in the length direction of the wire diameter is evaluated, and the result is a variation coefficient [standard deviation defined in JIS-Z8101-1. The value represented by (σ) / average value × 100] was defined as the wire diameter variation rate.

[Spinning operability]
The state during continuous extrusion spinning was observed, and the frequency of yarn breakage in the drawing process was evaluated according to the following three criteria.
○ ・ ・ All were good,
△ ・ ・ Although thread breakage occurred, it was able to operate sufficiently.
× ·· Many yarn breaks occurred, making operation extremely difficult.

[Dry powder calcium carbonate wear fracture number]
A load of 0.20 cN / dtex was applied to one end of the polyester monofilament, the other end was connected to a sliding device, and the sample was reciprocated 120 in a calcium carbonate powder perpendicularly and in contact with a SUS metal friction element. The sample was slid at a speed of times / min, and the number of sliding times until the sample broke was measured as the number of breaks. Then, for each of the five polyester monofilaments for the same sample, the number of ruptures / reciprocation until rupture was measured, and the average value was defined as the dry powder calcium carbonate wear rupture number.

[Example 1]
The dried polyethylene terephthalate virgin pellets and calcium carbonate having an average particle size of 0.29 μm and a particle size distribution ratio of 1.58 are mixed, supplied to a uniaxial extruder, melt-kneaded at 280 ° C., The gut that was extruded from the nozzle at the tip, guided to the cooling water tank and cooled, was cut to obtain polyethylene terephthalate pellets (hereinafter referred to as pre-kneaded pellets) containing 20% by weight of calcium carbonate.

  Next, the polyethylene phthalate pellets and the pre-kneaded pellets are fed to a single-screw extruder type spinning machine while being metered so that the calcium carbonate content in the monofilament composition is 5.0%, and melt kneaded at 290 ° C. The polyester monofilament having a circular cross section with a diameter of 0.40 mm was obtained by spinning, cooling in a hot water bath at 90 ° C., stretching 5.3 times at 180 ° C., and then setting heat at 0.95 times. . The distance between the nozzle cooling water tanks was 5 cm.

  Table 1 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate wear fracture number of the obtained monofilament.

[Examples 2 to 5]
A polyester monofilament having a diameter of 0.40 mm was prepared in the same manner as in Example 1 except that the average particle size of calcium carbonate to be mixed, the particle size distribution ratio, and the calcium carbonate content in the monofilament composition were changed as shown in Table 1. Obtained.

  Table 1 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate abrasion breakage.

[Comparative Examples 1-5]
A polyester monofilament having a diameter of 0.40 mm was prepared in the same manner as in Example 1 except that the average particle size of calcium carbonate to be mixed, the particle size distribution ratio, and the calcium carbonate content in the monofilament composition were changed as shown in Table 1. Obtained.
Table 1 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate abrasion breakage.

[Example 6]
The dried polyethylene terephthalate virgin pellets and titanium dioxide having an average particle size of 0.31 μm and a particle size distribution ratio of 1.62 are mixed, supplied to a uniaxial extruder, melt-kneaded at 280 ° C., The gut that was extruded from the nozzle at the tip and guided to the cooling water tank and cooled was cut to obtain polyethylene terephthalate pellets (hereinafter referred to as pre-kneaded pellets) containing 20% by weight of titanium dioxide.

  Next, Example 1 was carried out except that the polyethylene phthalate pellets and the pre-kneaded pellets were fed to a single-screw extruder type spinning machine while measuring so that the titanium dioxide content in the monofilament composition was 5.0%. A polyester monofilament having a circular cross section with a diameter of 0.40 mm was obtained in the same manner as described above.

  Table 2 shows the tensile strength, the wire diameter fluctuation rate, and the dry powder calcium carbonate abrasion breakage of the obtained monofilament.

[Examples 7 to 10]
A polyester monofilament having a diameter of 0.40 mm was prepared in the same manner as in Example 6 except that the average particle diameter of titanium dioxide to be mixed, the particle size distribution ratio, and the titanium dioxide content in the monofilament composition were changed as shown in Table 2. Obtained.

  Table 2 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate abrasion breakage.

[Comparative Examples 6-9]
A polyester monofilament having a diameter of 0.40 mm was prepared in the same manner as in Example 6 except that the average particle diameter of titanium dioxide to be mixed, the particle size distribution ratio, and the titanium dioxide content in the monofilament composition were changed as shown in Table 2. Obtained.

  Table 2 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate abrasion breakage.

[Example 11]
The dried polyethylene terephthalate virgin pellets and silicon dioxide having an average particle size of 0.28 μm and a particle size distribution ratio of 1.80 are mixed, supplied to a uniaxial extruder, melt-kneaded at 280 ° C., The gut that was extruded from the nozzle at the tip and guided to the cooling water tank and cooled was cut to obtain polyethylene terephthalate pellets (hereinafter referred to as pre-kneaded pellets) containing 20% by weight of silicon dioxide.

  Next, Example 1 was carried out except that the polyethylene phthalate pellets and the pre-kneaded pellets were fed to a single-screw extruder type spinning machine while measuring so that the silicon dioxide content in the monofilament composition was 5.0%. A polyester monofilament having a circular cross section with a diameter of 0.40 mm was obtained in the same manner as described above.

  Table 3 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate wear fracture number of the obtained monofilament.

[Examples 12 to 15]
A polyester monofilament having a diameter of 0.40 mm was prepared in the same manner as in Example 11 except that the average particle size of silicon dioxide to be mixed, the particle size distribution ratio, and the silicon dioxide content in the monofilament composition were changed as shown in Table 3. Obtained.

  Table 3 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate abrasion breakage.

[Comparative Examples 10 to 13]
A polyester monofilament having a diameter of 0.40 mm was prepared in the same manner as in Example 11 except that the average particle size of silicon dioxide to be mixed, the particle size distribution ratio, and the silicon dioxide content in the monofilament composition were changed as shown in Table 3. Obtained.

  Table 3 shows the tensile strength, the wire diameter variation rate, the average particle size and the particle size distribution ratio of the particles in the fiber, and the dry powder calcium carbonate abrasion breakage.

  As is clear from the results in Tables 1 to 3, the polyester monofilaments (Examples 1 to 15) in the present invention have high wear resistance and have the tensile strength and the wire diameter variation rate required for industrial fabrics. I understand that.

  On the other hand, polyester monofilaments obtained without satisfying the production conditions of the present invention, that is, monofilaments in which the average particle size and particle size distribution ratio of the inorganic particles deviate from the definition of the present invention (Comparative Examples 2-3, 6-7). 10-11) have low wear resistance and do not have the tensile strength and the wire diameter fluctuation rate required for industrial fabrics.

  Moreover, the monofilaments (Comparative Examples 4-5, 8-9, 12-13) whose inorganic particle content in the monofilament composition exceeded the provisions of the present invention can satisfy the wear resistance if the content is low. In addition, if the content is high, the tensile strength and the wire diameter fluctuation rate required as an industrial fabric cannot be satisfied, and the operability is unstable.

  The polyester monofilament of the present invention is excellent in abrasion resistance, has small fluctuations in wire diameter and good surface smoothness, and has a necessary and sufficient tensile strength as an industrial fabric. Useful as a constituent material.

Claims (12)

With respect to the polyester resin, the average particle diameter is 0.2 to 1.0 μm, and d25 / d75 (d25: particle size based on the volume distribution of particles, the particle diameter at 25% of the total volume from the large particle diameter side, d75: Resin composition containing 1 to 15% by weight of inorganic particles having a particle size distribution ratio of 2.5 or less in terms of a volume-based cumulative distribution of particles, the particle size distribution ratio represented by 75% of the total volume from the large particle size side) A polyester monofilament characterized by comprising: The polyester monofilament according to claim 1, wherein the monofilament has a wire diameter of 0.1 mm or more and 2.0 mm or less. The polyester monofilament according to claim 1 or 2, wherein the inorganic particles are at least one selected from calcium carbonate, titanium dioxide, and silicon dioxide. The polyester monofilament according to any one of claims 1 to 3, wherein the polyester-based resin is mainly composed of at least one selected from polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate. The polyester monofilament according to claim 4, wherein the polyester resin is polyethylene terephthalate, and the carboxyl terminal concentration is 10 equivalents / ton or less. The polyester monofilament according to claim 1, wherein the monofilament has a wire diameter variation rate of 4.0 or less. 7. The polyester monofilament according to claim 1, wherein the monofilament has a tensile strength of 2.0 cN / dtex or more measured according to JIS L-1013: 1999-8.5. 8. The polyester monofilament according to claim 1, wherein the dry breakage of the calcium carbonate carbonate measured by the following method is 200 times or more / reciprocation.
[Measurement method of dry powder calcium carbonate wear rupture frequency]
A load of 0.20 cN / dtex is applied to one end of the polyester monofilament, the other end is connected to a sliding device, and the sample is reciprocated 120 times in a calcium carbonate powder at right angles to and in contact with a SUS friction element. The sample was slid at a speed of / min, and the number of slides until the sample broke was measured as the number of breaks. Then, for each of the five polyester monofilaments for the same sample, the number of ruptures / reciprocation until rupture was measured, and the average value was defined as the dry powder calcium carbonate wear rupture number. A woven fabric comprising the polyester monofilament according to any one of claims 1 to 8 as at least a part of warp and / or weft. The woven fabric according to claim 9, which is an industrial woven fabric. The industrial fabric according to claim 10, which is a papermaking fabric. The woven fabric according to claim 11, which is a fabric for a paper-making dryer canvas.