JP2008019528A - Stainproof polyester conjugate monofilament having sheath-core structure and industrial woven fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stainproof polyester monofilament having excellent stainproof properties against gum pitch and sufficient strength, and useful as a component material of a woven fabric for papermachine, such as a papermaking wire and a papermaking dryer canvas. <P>SOLUTION: The polyester monofilament having sheath-core structure comprises a core component and a sheath component both composed of a polyester. The sheath component contains 0.01-15.0 pts.wt. of 34-65C higher aliphatic monocarboxylic acid ester compound as a component except the polyester based on 100 pts.wt. of polyester, and the monofilament has a strength of ≥5.5 cN/dtex. The industrial woven fabric is obtained by using the monofilament. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to an antifouling core-sheath composite polyester monofilament having excellent antifouling properties and sufficient strength required for industrial fabrics such as papermaking wires, and an industrial fabric comprising the same.

  Fibers made of thermoplastic resins such as polyester, polyphenylene sulfide, and polyamide have excellent tensile strength and heat resistance, so they have been used in various industrial parts, clothing and industrial fiber materials, and various textiles. Have been used.

  Examples of these woven fabrics include polyester monofilaments for paper machines, filters, and net conveyors for thermal bonding non-woven fabric thermal bonding processes, and other uses such as various brushes, brushes, and printing screens. Widely used for fishing line, rubber reinforcing fiber material, etc.

  Among them, monofilaments are widely used as constituent materials in papermaking industry, such as papermaking wire for paper machines (paper weaving fabrics), paper press felt (paper weaving process fabrics) and paper dryer canvas (textile for paper drying processes). Have been used.

  However, in the papermaking process, various adhesives, slime, wood pitch, etc. present in the paper raw materials or adhesive properties such as gummed tape adhesive glue that has been attached to the recovered corrugated paper raw material due to the popularization of recycled recovered paper from the viewpoint of resource protection in recent years When dirt (hereinafter abbreviated as "gum pitch dirt") adheres to the papermaking fabric made of thermoplastic resin fibers, the drainage efficiency, the squeezing efficiency and the drying efficiency are reduced. In addition to causing problems such as susceptibility to contamination, deterioration of the quality of product paper due to transfer of these contaminants to paper has become a serious problem.

In order to solve such a problem, various proposals have been conventionally made.
For example, a polyester monofilament containing a melt-kneaded polysiloxane (for example, see Patent Document 1), a polyester monofilament to which a fluorine-based polymer is added (for example, see Patent Document 2), a fluorine-based polymer, and the like Polyester monofilament containing silicone oil (for example, see Patent Document 3), core / sheath composite polyester monofilament containing sheathed fluorine polymer and silicone oil (for example, see Patent Document 4), polyethylene, polypropylene, polybutene, poly Polyester monofilaments added with a specific amount of polyolefin such as -4-methylpentene 1 and polystyrene (for example, see Patent Document 5) are known, but these monofilaments are adhesive such as gum pitch. Is intended antifouling properties is still inadequate for dirt, further improvement has been desired.
JP-A-60-81313 (pages 1 to 4) Republished International Publication Number WO 92/07126 (pages 1 to 11) JP 2004-308090 A (pages 1 to 18) JP 2004-292960 A (pages 1 to 21) JP 51-136923 A (pages 1 to 5)

  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.

  Therefore, the object of the present invention is to have excellent antifouling properties (hereinafter abbreviated as gum pitch antifouling property) and sufficient strength such that the gum pitch stains are difficult to adhere and the attached gum pitch stains are easy to wash. In particular, an object of the present invention is to provide an antifouling monofilament suitable as a constituent material of a paper machine fabric such as a paper machine wire, a paper machine dryer canvas, and a paper machine press felt, and various industrial fabrics using the same.

  In order to achieve the above object, according to the present invention, the core component and the sheath component are both core-sheath composite polyester monofilaments made of polyester, and the sheath component is a component other than polyester having 34 to 34 carbon atoms. 65 high aliphatic monocarboxylic acid ester compound is contained 0.01 to 15.0 parts by weight with respect to 100 parts by weight of polyester, and the strength measured according to JIS L1013-1992 is 5.5 cN / An antifouling core-sheath composite polyester monofilament characterized by having a dtex or more is provided.

In the antifouling core-sheath composite monofilament of the present invention,
The sheath component contains 0.05 to 10.0 parts by weight of a higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms with respect to 100 parts by weight of the polyester,
The higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms is a wax derived from a natural plant;
The higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms is dispersed with a dispersion diameter of 10 μm or less in a cross section perpendicular to the axial direction of the monofilament,
The polyester is polyethylene terephthalate;
The core-sheath composite weight ratio of the core component and the sheath component is: core component / sheath component = 50 to 95/50 to 5, and the cross section perpendicular to the monofilament axial direction is circular or flat. It is mentioned as a preferable condition, and acquisition of a more excellent effect can be expected by satisfying at least one of these conditions.

  The industrial fabric of the present invention is characterized in that the antifouling core-sheath composite monofilament is used as at least a part of a weft and / or a warp, particularly a paper machine fabric, a filter fabric or a thermal bond method. It is desirable to use it as a fabric for a net conveyor for a thermal bonding process of a nonwoven fabric and a fabric for a conveyor belt in a heat treatment furnace.

  The industrial fabric of the present invention is preferably a papermaking wire or a papermaking dryer canvas, and particularly in the case of a papermaking wire, the average diameter measured by the following method is 0.05 to 0.50 mm. It is desirable that it is made of a monofilament having a circular cross section with a diameter variation rate of ± 5% or less with respect to the diameter.

[Measurement method of monofilament diameter (wire diameter patch rate)]
(1) Measure 30 diameters (mm) up to 3 digits after the decimal point in the length direction of the monofilament using a laser contour measuring instrument (SLB DIA MEASURING SYSTEM KL151A manufactured by Anritsu Co., Ltd. or equivalent).
(2) The average diameter (X) of 30 measured values is calculated (the fourth decimal place is rounded off to the third decimal place).
(3) The wire diameter unevenness rate is obtained by the following equation from the average diameter (X) of 30 measured values, with the difference between the maximum diameter value (A) and the minimum diameter value (B) of each measured value as the wire diameter unevenness.
{(A)-(B)} / (X) × 100 = line diameter spot rate (%)

  According to the present invention, as described below, the gum pitch dirt is less likely to adhere than the conventional one, and has excellent antifouling properties against gum pitch dirt such as easy cleaning of the attached gum pitch dirt, and at the same time sufficient It is possible to obtain an antifouling core-sheath composite monofilament having various strengths and particularly suitable as a constituent material of a paper machine fabric such as a papermaking wire, a papermaking dryer canvas, and a papermaking press felt, and various industrial fabrics using the same.

  The present invention is described in detail below.

  The polyester referred to in the present invention is a polyester composed mainly of dicarboxylic acid and glycol. Examples of the dicarboxylic acid component include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, and the like. Examples of the glycol component include ethylene glycol, propylene glycol, tetramethylene glycol, 1,4-cyclohexanedimethanol and the like. These dicarboxylic acid components and glycol components can be used in appropriate combination. In addition, a part of the dicarboxylic acid component may be replaced with adipic acid, sebacic acid, dimer acid, sulfonic acid metal salt-substituted isophthalic acid, etc., and a part of the glycol component may be diethylene glycol, neopentyl glycol, 1 , 4-cyclohexanediol, polyalkylene glycol, etc. may be substituted. Furthermore, a small amount of chain branching agents such as pentaesitol, trimethylolpropane, trimellitic acid, trimesic acid, boric acid can be used in combination.

  Among these, polyethylene terephthalate (hereinafter abbreviated as PET) in which 90 mol% or more of the dicarboxylic acid component is made of terephthalic acid and 90 mol% or more of the glycol component is made of ethylene glycol is preferable.

In order to efficiently express the effect of the present invention, the phosphorus compound can be contained in PET in an amount of 50 ppm or less as a phosphorus atom and within the range of the following general formula 1.
5 × 10−3 ≦ P ≦ M + 8 × 10−3 Formula 1
(In the formula, P is the mol% of the phosphorus atom with respect to the dibasic acid constituting PET, M is a metal in the PET resin, and is Group II, Group VII, Group VIII, and (It is the mol% with respect to the dibasic acid which comprises the polyester of the 1 type (s) or 2 or more types of metal atom selected from the period. M = 0 may be sufficient.)

  The above-mentioned polyester can contain various known organic and inorganic additives depending on the purpose. For example, different types of thermoplastic resins, various synthetic / polymerization catalyst residues, various antioxidants, light fasteners, Anti-aging agent such as flame retardant, copper iodide, potassium iodide, inorganic particles and pigments such as titanium oxide, silicon oxide, calcium carbonate, silicon nitride, silicon carbide, barium sulfate, clay, talc, kaolin, carbon black, Various organic pigments such as phthalocyanine metal, cobalt blue, stearic acid metal salts, ethylene bisstearylamide, stearic acid, calcium metasilicate, hydrous magnesium silicate, aminosilane, melamine cyanurate, ionomer, sequestering agent, inclusion compound , Anti-coloring agent, antistatic agent, silicone oil, various surfactants, various reinforcing fibers S, and when the thermoplastic resin is a saturated polyester may contain various carbodiimide compounds for improving the hydrolysis resistance and drought thermally decomposable, various epoxy compounds and various oxazoline compound.

  Further, when the antifouling core-sheath composite polyester monofilament of the present invention is used for textiles for paper making dryer canvases, carbodiimides such as monocarbodiimides and polycarbodiimides having one or more carbodiimide groups in one molecule. A compound, a mono- or diepoxy compound, a mon or bisoxazoline compound, and various polyolefin resins, fluorine resins, and the like can also be blended.

  The intrinsic viscosity of the polyester to be used is usually 0.5 or more, but preferably 0.6 or more, more preferably 0.7 or more, because the obtained monofilament has excellent strength properties.

  For the polyester constituting the antifouling core-sheath composite polyester monofilament of the present invention, a method of producing a high molecular weight polyester by solid phase polycondensation subsequent to melt polymerization can also be preferably employed. In particular, when polyester monofilament is a constituent material for industrial fabrics, solid-phase polycondensation subsequent to melt polymerization can be achieved by increasing the molecular weight of polyester and the concentration of carboxyl end groups (hereinafter referred to as COOH end group concentration). Is preferable.

  Further, the sheath component of the antifouling core-sheath composite polyester monofilament of the present invention needs to contain a higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms as a component other than polyester. As this ester compound, a carbon atom obtained by esterifying part or all of a higher aliphatic monocarboxylic acid having 10 to 33 carbon atoms with a monovalent or divalent alcohol having 2 to 33 carbon atoms. The higher aliphatic monocarboxylic acid ester compound of several 34-65 is preferable, and the monofilament which has the outstanding gum pitch antifouling property can be obtained by containing a higher aliphatic monocarboxylic acid ester compound in a sheath component. In particular, a higher aliphatic monocarboxylic acid having 16 to 33 carbon atoms, and a higher aliphatic monocarboxylic acid having 40 to 62 carbon atoms obtained by esterification of a higher aliphatic monocarboxylic acid having 20 to 32 carbon atoms. The use of ester compounds is preferred.

  When the number of carbon atoms of the higher aliphatic monocarboxylic acid ester compound is less than 34, due to the low molecular weight of the ester compound, the resulting polyester deteriorates or scatters when monofilarized, resulting in spinning. Not only does the base stain become intense, the resulting polyester monofilament becomes more intensely colored, but also the strength is reduced and the wire diameter becomes large, and the gum pitch antifouling property is further deteriorated. Further, when the number of carbon atoms of the higher aliphatic monocarboxylic acid ester compound exceeds 65, compatibility with the polyester is deteriorated, and not only the strength of the monofilament is lowered, but also the diameter variation is large and the gum pitch antifouling property is deteriorated. .

  Specific examples of the higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms may be those produced industrially or naturally obtained. For example, those manufactured industrially include hexyl montanate, ceryl montanate, octacosyl lignocerate, merisyl lignocerate, ceryl lignocerate, melyl cellolate, ceryl serotate and the like. However, there is no limitation to this. In addition, naturally-derived plant-derived waxes, animal-derived waxes, petroleum-derived waxes, mineral-derived waxes, among others, carnauba wax, candelilla wax, nuka wax, bead wax, ibotarou, montan wax, etc. Is mentioned. However, there is no limitation to this.

  In particular, natural montan wax (main component: ester of 52 carbon atoms composed of monocarboxylic acid having 28 carbon atoms), carnauba wax (main component: carbon atoms composed of monocarboxylic acid of 26 carbon atoms) 56), beeswax (main component: ester having 46 carbon atoms composed of monocarboxylic acid having 16 carbon atoms) and the like are preferably used. Of these, carnauba wax, which is a wax derived from natural plants, is particularly preferable.

  Further, when the acid value of the higher aliphatic monocarboxylic acid compound ester compound having 34 to 65 carbon atoms is 5 or less, an effect of improving antifouling property of gum pitch can be expected. When the acid value exceeds 5, the gum pitch antifouling property tends to be difficult to obtain.

  The amount of the higher aliphatic monocarboxylic acid ester compound of the present invention is required to be 0.01 to 15.0 parts by weight, preferably 0.05 to 100 parts by weight of the sheath component polyester. 10.0 parts by weight, more preferably 0.1 to 5.0 parts by weight. If the content of the higher aliphatic monocarboxylic acid ester compound is less than 0.01 parts by weight, the gum pitch antifouling property is insufficient, and if it exceeds 15.0 parts by weight, coloring of the resulting polyester monofilament becomes intense, Further, since the monofilament tends to be softened, it tends to be difficult to obtain a uniform monofilament, and the tensile strength, hook strength and knot strength are impaired, which is not preferable.

  Further, the higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms in the polyester in the sheath component of the antifouling core-sheath composite polyester monofilament of the present invention is dispersed in the form of particles, and the dispersion diameter is It is preferable that it is 10 micrometers or less, More preferably, it is 8 micrometers or less, More preferably, it is 5 micrometers or less. If the dispersion diameter exceeds 10 μm, the polyester monofilament may have insufficient gum pitch antifouling property or may impair strength properties and the like.

  In the antifouling core-sheath composite polyester monofilament of the present invention, the water contact angle on the surface of the monofilament is preferably 78 ° or more, more preferably 80 ° or more so that the gum pitch is less likely to adhere and the gum pitch is easily peeled off. More preferably, it is more preferably 82 ° or more.

  In addition, the gum pitch antifouling property of the antifouling monofilament in the present invention is determined by a gum pitch antifouling index (higher aliphatic monocarboxylic acid having 34 to 65 carbon atoms) in a cloth adhesive gum tape peeling stress measurement test method by a cloth adhesive gum tape sticking peeling method. The monofilament to which no carboxylic acid ester compound is added is taken as 100), and the smaller the gum pitch antifouling index, the better. The gum pitch antifouling property tends to be ineffective when the gum pitch antifouling index exceeds 90.

  The antifouling core-sheath composite polyester monofilament in the present invention is a continuous yarn composed of one single yarn.

The shape of the cross section perpendicular to the fiber axis direction of the antifouling core / sheath composite polyester monofilament in the present invention (hereinafter, abbreviated as a cross sectional shape or a cross section) is a circle, a flat shape, a square shape, a half moon shape, a triangular shape, or a polygon having five or more angles It may have any cross-sectional shape such as a multi-leaf shape, a dock bone shape, a saddle shape and a horseshoe shape. When the monofilament of the present invention is used as a constituent material for industrial fabrics, the cross-sectional shape is preferably circular or flat. In particular, when the monofilament is a papermaking wire, the cross-sectional shape of the monofilament may be a circle or a flat shape from the viewpoint of effectively expressing paper lifting and antifouling properties and the flatness of the wire. preferable. The flat in the present invention means an ellipse, a square or a rectangle. In addition to an exact ellipse, a square or a rectangle defined mathematically, a shape substantially similar to an ellipse, a square or a rectangle, for example, a square and a rectangle. Includes shapes with rounded corners. In the case of an ellipse, the length of the major axis (LD) and the length of the minor axis (SD) intersecting at right angles at the center of the ellipse satisfy the following equation. It is preferable that the long side length (LD) and the short side length (SD) of the rectangle satisfy the following expression.
1.0 ≦ LD / SD ≦ 10.0

  The length of the line segment passing through the center of gravity of the monofilament cross section can be appropriately selected depending on the application, but is preferably 0.01 to 3.0 mm.

  The antifouling core-sheath composite polyester monofilament of the present invention has a strength measured in accordance with JIS L1013-1992 of 5.5 cN / dtex or more, preferably 6.0 cN / dtex or more. When the strength is less than 5.5 cN / dtex, when the belt is used as an endless belt-like fabric by folding back both ends of the fabric using monofilaments as warp yarns and connecting the warp loops through weft yarns, the longitudinal tension of the belt In some cases, the warp loop part cannot endure, and the warp of the connection part breaks.

  The core-sheath composite weight ratio in the antifouling core-sheath composite polyester monofilament of the present invention can be arbitrarily designed, but the case where the core-sheath composite weight ratio is core component / sheath component = 50 to 95/50 to 5 is a monofilament. From the standpoints of the strong holding effect, imparting antifouling property of gum pitch, and sustainability of antifouling. More preferably, the core-sheath composite weight ratio is core component / sheath component = 70 to 90 / 30-10. On the other hand, when the weight ratio of the sheath component exceeds 50, the cross-sectional ratio of the core mainly holding the physical characteristics of the composite polyester monofilament becomes small, so that the physical characteristics such as strength may be inferior. Further, when the weight ratio of the sheath component is less than 5, the sheath portion may be worn due to the mechanical properties in the spinning process and the spinning process, and the core portion may be exposed. Not only is the effect not expected, but physical properties such as physical properties and quality are inferior.

  Further, when the antifouling core-sheath composite polyester monofilament of the present invention is used as a constituent material of a papermaking wire, it is preferably a monofilament having a circular cross section with a wire diameter spot rate of ± 5% or less with respect to the average diameter of the monofilament. . It is more preferable that the wire diameter spot rate is ± 3% or less. Papermaking wire is used in the process where the basic surface state and uniformity of the paper is formed by lifting the pulp from the dispersion containing pulp as the main component and sucking water. This is the application where the uniformity of the wire diameter is most needed. When the average diameter of the monofilament is 0.05 to 0.50 mm and the above-mentioned wire diameter unevenness ratio is ± 5% or less, the surface and the weave structure become a papermaking wire, and the water from the high-moisture pulp that has been fried is drawn. Since it can be performed uniformly, it is possible to obtain a preferable effect that a paper having a uniform thickness and excellent surface characteristics can be produced.

  In addition, the measuring method of the diameter (wire diameter spot rate) of the core-sheath composite monofilament in this case is as described above.

The method for producing the antifouling core-sheath composite polyester monofilament of the present invention comprises using a known core-sheath composite spinning machine, using polyester as the core component and a higher aliphatic monocarboxylic acid ester having 34 to 65 carbon atoms as the sheath component. It can be produced by supplying a polyester containing a compound, melt-kneading various additives as required, and then melt spinning.
Moreover, as a method of blending a higher aliphatic monocarboxylic acid ester compound with the sheath component of the antifouling core-sheath composite polyester monofilament of the present invention, A. A method for obtaining polyester pellets by adding and kneading at any time before, during, or immediately after the completion of the polyester polymerization reaction; A method of obtaining polyester pellets by adding and mixing in a monoaxial or biaxial extruder; There is a method of obtaining a high concentration polyester master pellet of a higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms by the methods A and B.

  Following the above, for example, a method of using polyester pellets kneaded in A or B, a method of blending a predetermined amount of high-density polyester master pellets of C with the same type of polyester pellets, or adding them during spinning, or polyester pellets and 34 carbon atoms A method of blending with a higher aliphatic monocarboxylic acid ester compound of ~ 65, a method of adding a higher aliphatic monocarboxylic acid ester compound of 34 to 65 carbon atoms directly into a spinning machine, etc. The antifouling core-sheath composite monofilament of the present invention can be produced by a method of spinning, stretching, heat setting, etc.

  The antifouling core-sheath composite polyester monofilament of the present invention thus obtained has excellent gum pitch antifouling properties and sufficient strength, and is useful as a constituent material for various industrial fabrics.

  Therefore, the various industrial fabrics comprising the antifouling core-sheath composite polyester monofilament of the present invention have sufficient strength, are difficult to adhere to the wood pitch and gum pitch stains, and wash the adhered gum pitch stains. Antifouling property such as easy to do is superior to conventional ones, and has high industrial utility value.

  The industrial fabric of the present invention is the above-described antifouling core-sheath composite monofilament of the present invention used for at least part of the weft and / or warp. In addition to being used as a single continuous yarn consisting of a single yarn, a combination of a plurality of continuous yarns consisting of this single yarn, and a single yarn consisting of a combination of multiple yarns What is necessary is just to use a thing etc. as at least one part of the warp and / or the weft which comprise a textile fabric. Specific examples of these industrial fabrics include a paper machine fabric, a fabric for a net conveyor for thermal bonding of a thermal bond nonwoven fabric, a fabric for a conveyor belt in a heat treatment furnace, and various filter fabrics.

  Furthermore, the paper machine fabric can be suitably used as the monofilament for the constituent material of the paper making wire or paper dryer canvas, and has an unprecedented excellent gum pitch antifouling property, and has high industrial utility value. Is.

  Here, the papermaking wire is a woven fabric used in a paper winding process as various woven fabrics such as plain weave, double weave, and triple weave, and is used as a long mesh or a round mesh. The paper dryer canvas is a paper machine as various fabrics such as plain weave, double weave, and triple weave (including spiral fabrics in which wefts and wefts that follow each other are woven by spiral monofilaments). It is a fabric used for drying paper in a dryer.

  In addition, the fabric for the net conveyor for the thermal bonding process of the thermal bond method nonwoven fabric is for passing the nonwoven fabric through a furnace in order to fuse the thermal adhesive fibers such as low melting point polyethylene constituting the nonwoven fabric. A woven fabric, such as a plain weave or a double weave.

  In addition, the fabric for the conveyor belt in the heat treatment furnace refers to a fabric that transports the semi-finished product in the high temperature zone for drying, thermosetting, sterilizing, heating cooking, and the like of various semi-finished products.

  The various filter fabrics are fabrics that filter high-temperature liquids, gases, powders, and the like.

  In these, it is especially suitable as a constituent material of the papermaking wire by which especially outstanding gum pitch antifouling property is requested | required.

  Hereinafter, the present invention will be described in more detail with reference to examples.

  The characteristic values in the following examples are measured by the following methods unless otherwise specified in each example.

1. Intrinsic viscosity The intrinsic viscosity of the polyester is the intrinsic viscosity obtained from a viscosity measured at 25 ° C. by adjusting a 0.1 g / 10 ml orthochlorophenol solution, and is represented by [η].

2. Method for measuring the carboxyl end group concentration of polyester (hereinafter referred to as COOH end group concentration) 0.5 g of a polyester sample was dissolved in 10 ml of o-cresol, cooled completely, cooled, added with 3 ml of chloroform, and then added with a methanol solution of NaOH. The value obtained by performing potentiometric titration.

3. Strength of monofilament Tensile test of monofilament A tensile tester (Tensilon / UTM-III-100 manufactured by Orientec Co., Ltd.) was used according to JIS L1013-1992.

4). Monofilament diameter (line diameter patch rate)
(1) Measure 30 diameters (mm) up to 3 digits after the decimal point in the length direction of the monofilament using a laser contour measuring instrument (SLB DIA MEASURING SYSTEM KL151A manufactured by Anritsu Co., Ltd. or equivalent).
(2) The average diameter (X) of 30 measured values is calculated (the fourth decimal place is rounded off to the third decimal place).
(3) The wire diameter unevenness rate is obtained by the following equation from the average diameter (X) of 30 measured values, with the difference between the maximum diameter value (A) and the minimum diameter value (B) of each measured value as the wire diameter unevenness.
{(A)-(B)} / (X) × 100 = line diameter spot rate (%)

5. Color tone About 13 g of a sample obtained by cutting a monofilament to about 5 mm is placed in a glass cell dedicated to a color computer (manufactured by Suga Test Instruments Co., Ltd .: touch panel SM color computer SM-T), measured five times with a color computer, and the average value is color tone (B value). As the b value is larger, it tends to be yellowish.

6). Dispersion diameter evaluation method of higher aliphatic monocarboxylic acid having 10 to 33 carbon yarns and / or higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms in antifouling monofilament with a single-blade razor in the monofilament axial direction A monofilament sample (about 2 mm) cut vertically is attached to a conductive tape affixed to an SEM sample stage so that the cross section of the sample is parallel to the upper part of the SEM sample stage, and a platinum-palladium alloy is deposited for 1 minute 30 seconds (deposition machine: HITACHI's E101 ION SPUTTER) and observe the entire cross section of the monofilament with a scanning electron microscope (Nikon's E (Environmental) SEM) (where there is no razor mark) and select the one with the largest dispersion diameter Find the maximum diameter passing through the center of gravity of the dispersion surface as the diameter of the circle in μm units, up to one decimal place . This operation was repeated 10 times, and the average dispersion diameter in 10 data was obtained and used as the dispersion diameter of the additive.

7). Water contact angle on the surface of monofilament One monofilament was fixed on the surface of a glass plate with a length of 20 mm and a width of 5 mm with double-sided adhesive tape, and used as a measurement sample. In an atmosphere of 20 ° C., a goniometer manufactured by Elma Optical Co., Ltd. It set on the sample stand, 2 microliters was made to adhere to the monofilament surface of this measurement sample with the micro syringe, and the adhesion angle (degree) of the water droplet was measured. This measurement operation was repeated 10 times, the maximum value and the minimum value of the measurement were removed, and the average value was taken as the water contact angle on the monofilament surface.

8). Gum pitch antifouling index of polyester monofilament The peel stress value is determined by the cloth adhesive gum tape peeling stress measurement test (hereinafter referred to as cloth adhesive gum tape peeling test) by the cloth adhesive gum tape affixing and peeling method shown below. Asked.
Test peel stress value / Comparative sample peel stress value × 100 = Gum pitch antifouling index

By measuring the peeling stress of cloth adhesive gum tape, it is possible to quantitatively evaluate the antifouling property against gum pitch stains of paper machine fabrics, etc., made of the target monofilaments, without processing the monofilaments into fabrics. The gum pitch antifouling index of less than 90 was set as the target value.
(1) Two biaxially stretched films made of polyethylene terephthalate having a thickness of 150 to 250 μm, a width of 30 mm, and a length of 120 mm are prepared.
(2) A double-sided adhesive tape (Nitto Denko Corporation product, No. 523 or equivalent) with a width of 10 mm and a length of 120 mm is pasted on the center of the length direction of one film, and cut to a length of about 200 mm. The polyester monofilament sample was affixed to the double-sided adhesive tape on the film without any gaps in parallel with the longitudinal direction of the double-sided adhesive tape, and the remaining ends of the monofilament protruding from both ends of the double-sided adhesive tape were removed with scissors, A monofilament sample affixing film is obtained.
(3) With the monofilament sample application surface facing up, 30 mm width of the monofilament sample application film and one end of the other film 30 mm width are aligned so as not to overlap each other, and an adhesive is applied to one side of the lower surface of the alignment surface A film having an apparent length of about 240 mm and a width of 30 mm is formed by pasting a cloth adhesive tape of 25 mm × 25 mm so as to extend over both ends of the two films, and joining them in the vertical direction at the joint. .
(4) After the monofilament sample application surface is on top and the monofilament surface is on the left side, the joined film having an apparent length of about 240 mm and a width of 30 mm is a glass plate (thickness: about 8 mm, length: about (300mm, width approximately 80mm) Set in the center.
(5) Longitudinal direction of cloth adhesive gum tape (made by Nichiban Co., Ltd., strong adhesive tape for cardboard packaging <LS> No. 101N or equivalent) with adhesive applied to one side cut to a width of 10 mm and a length of 150 mm Align the left end with the left end of the monofilament surface of the monofilament sample affixing film, and temporarily affix a cloth adhesive gum tape on the monofilament. Next, the cloth adhesive tape remaining about 30 mm at the right end of the monofilament surface is attached to one film surface.
(6) Turn over the monofilament adhesive film, and remove the 25 mm × 25 mm size cloth adhesive tape coated with an adhesive on the one surface, which was adhered to connect the two films in (3).
(7) The cloth temporarily set on the surface of the monofilament, set so that the monofilament sticking surface of the monofilament sticking film faces upward and the monofilament face is on the left side so as to be completely on the glass plate A rubber roller having a weight of 1.43 kg, a width of 50 mm, and a diameter of 86 mm is run on the adhesive gum tape at a speed of about 10 seconds / 120 mm from the right longitudinal direction to the left edge of the film on which the cloth adhesive gum tape is overlaid to adhere the fabric. A sample for measuring the tape peeling stress is prepared.
(8) The cloth adhesive is folded on the monofilament from the fold fulcrum, with the joint of the two films as a fulcrum so that the surface of the cloth adhesive gum tape is on the inside. Peel the gum tape about 15 mm long, set the exposed end of the monofilament film to the center of the upper chuck of the tensile tester (Orientec Co., Ltd. Tensilon / UTM-III-100), and attach one monofilament. The lower end of the film (the hem of the mountain fold) is set at the center of the lower chuck of the tensile tester, and the peel stress is measured under the conditions of a tensile speed of 100 mm / min and a chart speed of 100 mm / min. A peel stress chart in which peaks having high peel stress and valleys having low peel stress are alternately connected is obtained.
(9) From the peak of the first peel stress of the obtained peel stress chart, the peak of the peel stress about 20 mm later is used as a starting point, and the peel stress values at 50 points are read in the order of peaks and valleys. This measurement operation ((1) to (9)) is repeated 10 times, and the average value is defined as the cloth adhesive tape peeling stress.

[Example 1, Comparative Example 1]
1. Polyester production method [η] 0.87 containing 0.4 parts by weight of titanium dioxide produced by known melt polycondensation and solid phase polycondensation (based on 100 parts by weight of PET), COOH end group concentration 13 equivalents / 10 ⁶ g of PET dry chip (hereinafter abbreviated as polyester (A)) was obtained.

2. Method for Producing Carnauba Wax-Containing Polyester A polyester (A) and carnauba wax (manufactured by Celerica NODA: purified carnauba wax NO1) (hereinafter abbreviated as C-wax) are charged into each nitrogen-sealed hopper, C- The wax is weighed from the hopper so as to be 20 parts by weight with respect to 100 parts by weight of the polyester (A), supplied to the biaxial extruder type kneader through the feeder, melt kneaded, and discharged into cold water in a strand form. Immediately cutting was carried out to obtain a C-wax kneaded polyester. [Η] of this kneaded polyester chip was 0.602, and the COOH end group concentration was 26.0 equivalent / 10 ⁶ g. The kneaded chips were dried with a vacuum dryer at 150 ° C. for 15 hours (hereinafter abbreviated as polyester (B)).

3. Method for producing antifouling core-sheath composite polyester monofilament A single-screw extruder spinning machine for core components using a feeder so that the polyester (A) is supplied to a nitrogen-sealed core component hopper and the core component is 85 parts by weight. The uniaxial extruder was melted at 287 ° C. for about 4 minutes and supplied to the core-sheath composite spinning pack through a gear pump. In addition, the polyester (A) and the dried polyester (B) are supplied to each hopper of the nitrogen-sealed sheath component amount, and the C-wax in the polyester (B) is the polyester component 100 of the polyester (A) and the polyester (B). Using a feeder so as to be 1 part by weight with respect to parts by weight, it is put into an intermediate hopper provided with kneading blades, and using the feeder so that the sheath component becomes 15 parts by weight, the uniaxial extruder type spinning for sheath component Continuously supplied to the machine, melted for about 5 minutes at a single-screw extruder at 283 ° C., and supplied to a core-sheath composite spinning pack via a gear pump. The weight ratio of the core component / sheath component was set to 85/15, and merged immediately before the nozzle discharge holes through the respective filtration layers, and the mixture was spun from a spinneret having a hole diameter of 1.2 mm and 8 holes. After cooling the spun monofilament in a 70 ° C. hot water bath, it was stretched in two stages according to a conventional method to a first stage 93 ° C. magnification of 3.6 times, a second stage 180 ° C. magnification of 1.528 times, and an overall magnification of 5.5 times. Heat setting was performed at 220 ° C. to obtain a circular cross-sectional core-sheath composite polyester monofilament having an average diameter of 0.250 mm.

  Table 1 shows the physical properties of the obtained core-sheath composite polyester monofilament. The monofilament strength is 6.4 cN / dtex, the monofilament gum tape peel stress is 198.7 cN / cm, and the monofilament monofilament monofilament of Comparative Example 1 has a gum pitch antifouling index of 100 and the monofilament gum pitch. The antifouling index was 69, and a polyester monofilament excellent in gum pitch antifouling property was obtained. This monofilament physical property is suitable as a constituent material of a papermaking wire which is a kind of industrial fabric.

  In Comparative Example 1, a monofilament was obtained in the same manner as in Example 1 except that only the core component extruder of Example 1 was used to obtain a monofilament having an average diameter of 0.250 mm. The monofilament gum tape peel stress was 288.0 cN / cm. Table 1 shows the physical properties of the monofilament.

[Examples 2 to 6, Comparative Example 2]
Examples 2 to 6 are examples in which the amount of C-wax contained in the sheath component of the core-sheath composite polyester monofilament of Example 1 was appropriately changed within the specified range of the present invention as shown in Table 1. In either case, a polyester monofilament excellent in gum pitch antifouling property was obtained.

  On the other hand, Comparative Example 2 is an example in which the amount of C-wax contained in the polyester monofilament of Example 1 is outside the specified range of the present invention, the strength of the monofilament is reduced, and the wire diameter unevenness is increased. The coloring was large and it was unsuitable as a constituent material for papermaking wire. Table 1 shows the physical properties of the monofilament.

Example 7
In Example 7, the C-wax contained in the polyester monofilament of Example 1 was changed to montan wax, and in this case as well, the polyester monofilament excellent in gum pitch antifouling property and suitable as a constituent material for papermaking wire is used. Obtained. Table 1 shows the physical properties of the monofilament.

[Comparative Examples 3 and 4]
Comparative Example 3 is an example in which the C-wax contained in the polyester monofilament of Example 1 is changed to butyl stearate having 22 carbon atoms, and Comparative Example 4 is a hexatetracontane having similarly 76 carbon atoms. This is an example in which the acid is changed to merisyl acid, which is outside the range of 34 to 65 carbon atoms of the higher aliphatic monocarboxylic acid ester compound defined in the present invention. It was inferior in soiling and unsuitable as a constituent material for papermaking wire. Table 1 shows the physical properties of the monofilament.

[Examples 8 and 9]
In Example 8, the core-sheath composite weight ratio of the core-sheath composite polyester monofilament of Example 1 was changed to core component / sheath component = 95/5, and Example 9 was changed to core component / sheath component = 60/40. Also in this case, a polyester monofilament excellent in gum pitch antifouling property and suitable as a constituent material of a papermaking wire was obtained. Table 1 shows the physical properties of the monofilament.

  The antifouling core-sheath composite polyester monofilament of the present invention has excellent antifouling properties against gum pitch stains and sufficient strength, and therefore is used for paper machine fabrics, thermal bond method nonwoven fabrics for net conveyors for thermal bonding processes. It is effective as a woven fabric, a fabric for a conveyor belt in a heat treatment furnace, or a fabric for various filters. Among them, it is used in a process of squeezing a woven paper making wire and a pulverized pulp used in a pulp making process in a paper machine process. It is useful as a constituent material of a papermaking dryer canvas in a process of drying a papermaking press felt base fabric and squeezed wet paper or coated paper, and is particularly suitable as a constituent material of a papermaking wire.

Claims (11)

Both the core component and the sheath component are core-sheath composite polyester monofilaments made of polyester, and the sheath component is a component other than polyester, and a higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms is added to 100 parts by weight of polyester. Antifouling core-sheath composite polyester comprising 0.01 to 15.0 parts by weight and having a strength measured in accordance with JIS L1013-1992 of 5.5 cN / dtex or more Monofilament. The said sheath component contains 0.05-10.0 weight part of higher aliphatic monocarboxylic acid ester compounds of 34-65 carbon atoms with respect to 100 weight part of polyesters, The claim | item 1 characterized by the above-mentioned. Antifouling core-sheath composite polyester monofilament. 3. The antifouling core-sheath composite polyester monofilament according to claim 1, wherein the higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms is a wax derived from a natural plant. 4. The higher aliphatic monocarboxylic acid ester compound having 34 to 65 carbon atoms is dispersed with a dispersion diameter of 10 [mu] m or less in a cross section perpendicular to the axial direction of the monofilament. The antifouling core-sheath composite polyester monofilament according to item 1. 5. The antifouling core-sheath composite polyester monofilament according to any one of claims 1 to 4, wherein the polyester is polyethylene terephthalate. 6. The antifouling property according to claim 1, wherein a core-sheath composite weight ratio of the core component and the sheath component is core component / sheath component = 50 to 95/50 to 5. Core sheath composite polyester monofilament. The antifouling core-sheath composite polyester monofilament according to any one of claims 1 to 6, wherein a cross section perpendicular to the monofilament axial direction is a circle or a flat shape. An industrial fabric, wherein the antifouling monofilament according to any one of claims 1 to 7 is used for at least a part of a weft and / or a warp. The industrial fabric according to claim 8, which is a fabric for a paper machine, a fabric for a net conveyor for a thermal bonding process of a thermal bond method nonwoven fabric, a fabric for a conveyor belt in a heat treatment furnace, or a fabric for various filters. The industrial fabric according to claim 9, which is a papermaking wire or a papermaking dryer canvas. The paper making wire is characterized in that the average diameter of monofilaments measured by the following method is 0.05 to 0.50 mm, and the wire diameter percentage with respect to the average diameter is a circular cross-section monofilament of ± 5% or less. The industrial fabric according to claim 10.
[Measurement method of monofilament diameter (wire diameter patch rate)]
(1) Measure 30 diameters (mm) up to 3 digits after the decimal point in the length direction of the monofilament using a laser contour measuring instrument (SLB DIA MEASURING SYSTEM KL151A manufactured by Anritsu Co., Ltd. or equivalent).
(2) The average diameter (X) of 30 measured values is calculated (the fourth decimal place is rounded off to the third decimal place).
(3) The wire diameter unevenness rate is obtained by the following equation from the average diameter (X) of 30 measured values, with the difference between the maximum diameter value (A) and the minimum diameter value (B) of each measured value as the wire diameter unevenness.
{(A)-(B)} / (X) × 100 = line diameter spot rate (%)