JP2007056392A - Flame retardant polyamide fiber and flame retardant fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide flame retardant polyamide fibers and fabrics not only excellent in physical properties such as strength and abrasion resistance and chemical properties such as flame retardance, weather resistance and chemical resistance, but also very small in flame retardance deterioration during practical use. <P>SOLUTION: The flame retardant polyamide fiber comprises polyamide multifilament having 1.5-100 dtex single fiber fineness, 4.5-9.0 cN/dtex strength and 5-15% boiling water shrinkage factor or polyamide monofilament having 80-80,000 dtex fineness and 4.5-9.0 cN/dtex strength, and contains 0.5-20 wt.% triazine-type compound having 0.1-2.3 μm average particle diameter and <5 μm maximum particle diameter. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a flame retardant polyamide fiber and a flame retardant fabric having flame retardancy, and more specifically, physical properties such as strength and abrasion resistance, and flame retardancy, weather resistance, chemical resistance, and the like. The present invention relates to a flame retardant polyamide fiber and a flame retardant fabric that are not only excellent in chemical characteristics of the above, but also have very little deterioration in flame retardant performance during practical use.

  Polyamide fibers are used for industrial materials such as tire cords, airbags, tents, tarpaulins, belts, ropes, land nets, and fishing nets, taking advantage of their high strength, toughness and excellent durability. Widely used.

  However, in industrial materials applications, in spite of many applications that require flame resistance in addition to the high strength, toughness, durability, etc. of polyamide fibers, the actual situation is that they have not been fully put into practical use. . The reason is that there was no suitable flame retardant to be blended with the polyamide fiber, and it was difficult to make it flame retardant. Therefore, a flame-retardant polyamide fiber having high strength and excellent weather resistance could not be obtained.

  As for the technology for imparting flame retardancy to a polyamide fiber excellent in weather resistance and abrasion resistance, it has been well known from the past. It has not been realized yet.

  For example, it is composed of 97 to 85% by weight of polyamide and 3 to 15% by weight of melamine cyanurate, and about 100% by weight of the melamine cyanurate has a particle size of 30 μm or less and 80% by weight or more and 7 μm or less. Flame retardant fibers having a single yarn diameter of 10 to 100 μm made of a polyamide composition dispersed therein (see, for example, Patent Document 1) have been proposed. According to this technology, the original properties of polyamide are impaired. It is claimed that a flame-retardant polyamide fiber having excellent flame retardancy can be obtained without any problems. However, in this technique, about 100% by weight of the melamine cyanurate is a flame-retardant fiber made of a polyamide composition having a particle size of 30 μm or less and 80% by weight or more and 7 μm or less dispersed in polyamide. Since the particle size of melamine cyanurate in the polyamide fiber is large, the flame-retardant polyamide fiber obtained has a strength of 4.5 to 4.9 g / d at most, and is demanded as an industrial fiber. The problem remains that the strength to be obtained is insufficient.

  Further, there has been proposed a flameproof artificial turf yarn (for example, see Patent Document 2) comprising 99.9 to 97.0 parts by weight of a polyamide resin and 0.1 to 3.0 parts by weight of a melamine flame retardant. According to the technology, it is claimed that a fireproof artificial turf yarn and a fireproof artificial turf that exhibit good flameproofness and can be used in places specified by the Fire Service Act or government ordinance are obtained. ing. However, in this technique, the use is limited to artificial turf use, and no consideration is given to the dispersibility of the melamine flame retardant, so the melamine flame retardant powder is used as described in the examples. The raw material is fed to the spinning machine at the same time as other raw materials, and the yarn is produced without taking any prescription for improving the dispersibility of the powder particles. As a result, coarse particles of the melamine flame retardant powder are produced in the fibers by secondary aggregation of the particles. It is possible that As a result, the strength of the flameproof artificial turf yarn obtained by this technology is at most about 3.5 to 4.5 g / d as described in the Examples, and the strength required for industrial fibers is as follows. It was insufficient.

And a flame retardant polyamide multifilament comprising a polyamide resin composition containing 98 to 80 parts by weight of a polyamide resin having a relative viscosity of 2.0 to 4.0 and 2 to 20 parts by weight of a triazine flame retardant. A flame retardant polyamide multi having a tensile strength measured by a measurement method based on JIS L 1013 of 2.0 cN / dtex or more and an average particle size of a triazine flame retardant dispersed in a multifilament is less than 5 μm Filaments (see, for example, Patent Document 3) have been proposed, and according to this technology, it is said that a safe polyamide multifilament excellent in flame retardancy and strength can be obtained without containing a halogen compound. However, since the average particle size of the triazine compound used in the examples of the technology is as large as 2.5 μm, the dispersion state of the triazine compound in the fiber is poor, and the triazine compound has a maximum particle size of 5 μm or more. When the compound is agglomerated secondaryly, it will be regarded as a foreign substance for the fiber. Therefore, the maximum strength of the obtained fiber is 4.4 cN / dtex. Had the problem of not being suitable. In addition, according to this technology, it is expected that multifilaments with a large single yarn fineness will exhibit the corresponding effects, but have recently been used to improve the high strength, toughness, durability, etc. of industrial materials. The flame retardancy of the single filament fineness multifilament that has come to be made has not been specifically disclosed.
JP 56-107012 A JP 2000-303257 A JP 2002-173829 A

  The present invention has been achieved as a result of studying the above-described problems in the prior art as a subject, and has been achieved by physical properties such as strength and wear resistance, and chemical properties such as flame retardancy, weather resistance, and chemical resistance. The object is to provide a flame retardant polyamide fiber and a flame retardant fabric that are not only excellent in mechanical properties but also have very little deterioration in flame retardant performance during practical use.

  To achieve the above object, according to the present invention, a polyamid multifilament having a single yarn fineness of 1.5 to 100 dtex, a strength of 4.5 to 9.0 cN / dtex, and a boiling water shrinkage of 5 to 15%, A flame retardant polyamide fiber containing 0.5 to 20% by weight of a triazine compound having an average particle size of 0.1 to 2.3 μm and a maximum particle size of less than 5 μm, and a fineness of 80 to 80,000 dtex, Polyamide monofilament with a strength of 4.5 to 9.0 cN / dtex, containing 0.5 to 20% by weight of a triazine compound having an average particle size of 0.1 to 2.3 μm and a maximum particle size of less than 5 μm A flame retardant polyamide fiber is provided.

In the flame-retardant polyamide fiber of the present invention,
The main dispersion peak temperature of loss tangent (tan δ) in dynamic viscoelasticity measurement is 103 to 120 ° C.,
The melting peak temperature of the DSC melting curve in the constant length constraint method is 227-280 ° C.,
Containing 0.5 to 10% by weight, preferably 0.5 to 1.9% by weight of the triazine compound,
The triazine compound is melamine cyanurate,
The flame retardant polyamide fiber further contains a copper compound as a copper metal amount of 10 to 500 ppm,
A preferable condition is that the polyamide fiber further contains 0.1 to 1% by weight of an organic or inorganic pigment.

  The flame-retardant fabric of the present invention is characterized by using the flame-retardant polyamide fiber described above.

  According to the present invention, as described below, not only is it excellent in physical properties such as strength and wear resistance and chemical properties such as flame retardancy, weather resistance and chemical resistance, but also while being put into practical use. It is possible to obtain a flame retardant polyamide fiber and a flame retardant fabric with extremely low flame retardant performance degradation.

  The present invention will be specifically described below.

  The flame-retardant polyamide fiber having high strength and excellent weather resistance according to the present invention is a polyamide having a single yarn fineness of 1.5 to 100 dtex, a strength of 4.5 to 9.0 cN / dtex, and a boiling water shrinkage of 5 to 15%. A flame retardant polyamide fiber, which is a multifilament and contains 0.5 to 20% by weight of a triazine compound having an average particle size of 0.1 to 2.3 μm and a maximum particle size of less than 5 μm, and A triazine-based compound having a fineness of 80 to 80,000 dtex and a strength of 4.5 to 9.0 cN / dtex, an average particle size of 0.1 to 2.3 μm, and a maximum particle size of less than 5 μm is 0.00. It is a flame retardant polyamide fiber characterized by containing 5 to 20% by weight.

  A technical feature that should be noted in the present invention is that a triazine compound having an average particle size of 0.1 to 2.3 μm and a maximum particle size of less than 5 μm is used, whereby 0.5 to 20% by weight of triazine is used. In the polyamide multifilament fiber, it is possible to obtain a high-strength polyamide fiber with good yarn-making property even if it contains a compound, and a triazine compound and the single yarn fineness satisfies the scope of the present invention. Because the surface area of the fiber is larger than that of fibers with a large single yarn fineness, the contact area between the flame-retardant triazine compound and the flame increases when burning fabrics that have been processed as industrial materials. It is to produce an effect.

  The triazine compound added to the flame retardant polyamide fiber of the present invention preferably has an average particle size of 0.1 to 2.3 μm, more preferably 0.1 to 1.5 μm, and most preferably 0.8. 1 to 1.0 μm. A triazine compound having an average particle size of less than 0.1 μm may be added to the polyamide polymer. However, the cost is increased and it is not practical. On the other hand, when the average particle size exceeds 2.3 μm, it becomes difficult to obtain a high-strength flame-retardant polyamide fiber suitable for industrial materials.

  The maximum particle size of the triazine compound is preferably less than 5 μm, more preferably 3.5 μm or less. When a triazine compound is used for the flame-retardant polyamide fiber of the present invention, if the maximum particle size of the triazine compound exceeds 5 μm, the probability of agglomeration with other triazine compounds in the molten polymer increases, and the spinning property Significantly decreases, and the dispersion state of the triazine compound in the fiber deteriorates, making it difficult to obtain high-strength fibers suitable for industrial materials. As a method for confirming the dispersion state of the triazine compound in the fiber, a yarn sample cut to 5 to 10 μm by a microtome is confirmed by a photograph taken at 400 to 500 times using an ECLIPSE E600W POL polarizing microscope manufactured by Nikon. Can do.

  The triazine compound having the above particle diameter can be obtained by a method such as dry classification after pulverizing the triazine compound by means of a ball mill or the like.

  Examples of the polyamide in the present invention include nylon 4, nylon 6, nylon 11 polycondensed from aminocarboxylic acid and its lactam, and polynylon 4-6, nylon 6-6, nylon obtained by polycondensation of dicarboxylic acid and diamide. Known polyamides such as 6-10 can be used. In addition, the polyamide fiber may contain a copolymer compound, a different polymer, or the like as long as the effect of the present invention is not impaired, preferably 10% by weight or less, and various light-proofing agents, flameproofing agents, Additives such as pigments, flame retardants, matting agents, and lubricants may be used.

  The single yarn cross section of the polyamide fiber of the present invention may be an irregular cross section other than a round cross section, and the irregular cross sectional shape may be a flat type, a triangular type, a C type, a Y type, a dumpling type, a hollow type, or those However, the present invention is not limited to this.

  Among the flame retardant polyamide fibers of the present invention, a flame retardant polyamide multifilament is required to have high strength as a material fiber, and therefore a high molecular weight polymer is used. The high molecular weight polymer referred to here is a high viscosity polymer having a relative viscosity of sulfuric acid of 3.0 to 5.0, preferably 3.5 to 4.5. If it is less than 3.0, it is difficult to obtain high-strength fibers. On the other hand, if it exceeds 5.0, it is difficult to produce yarn, and it is difficult to produce stable yarn with few yarn breakage and fluff at a yarn production speed of 3000 m / min or more.

  Moreover, the flame-retardant polyamide multifilament fiber of the present invention has a single yarn fineness of 1.5 to 100 dtex, and is a single yarn fineness suitable as a fiber for industrial materials. When the single yarn fineness is less than 1.5 dtex, the single yarn thickness is small compared to the size of the triazine compound, and there is a possibility that fluff and yarn breakage may occur in the fiber manufacturing process. In addition, when the single yarn fineness exceeds 100 dtex, there is a possibility that the stiffness of the fabric processed as an industrial material from the obtained multifilament is too strong, resulting in poor storage and workability.

  The flame-retardant polyamide fiber of the present invention has a strength of 4.5 to 9.0 cN / dtex, preferably 6.0 to 8.5 cN / dtex. If it is less than 4.5 cN / dtex, the strength as a fiber for industrial materials is not sufficient and cannot be useful. On the other hand, a flame-retardant polyamide fiber having a strength exceeding 9.0 cN / dtex can be obtained, but in that case, the yield of the yarn is inferior and a lot of fluff is generated, so that a flame-retardant polyamide fabric with good quality is obtained. I can't.

  When the flame-retardant polyamide fiber of the present invention is a multifilament, the boiling water shrinkage is required to be 5 to 15%, preferably 8 to 13%. As a result of heat treatment at a high temperature to sufficiently align the molecular chain as a high-strength polyamide multifilament fiber and to fix the high-strength fiber structure, it is necessary to have a boiling water shrinkage in the above range. is there. If the boiling water shrinkage rate is less than 5% or exceeds 15%, either a sufficient orientation is not achieved and only a low degree of orientation is obtained, or a heat treatment is not sufficiently performed and the fiber structure is not fixed. It is because it is not preferable because it hits.

  Next, when the flame-retardant polyamide fiber of the present invention is a monofilament, it is necessary that the single yarn fineness is 80 to 80,000 dtex and the strength is 5.0 to 9.0 cN / dtex.

  The fineness is 80 to 80000 dtex, preferably 80 to 20000 dtex. A high-strength flame-retardant monofilament of less than 80 dtex can also be obtained, but in this case, there are few suitable applications. On the other hand, in the case of a thick monofilament of more than 80000 dtex, a high-strength monofilament with a uniform cross-sectional inner and outer layers is obtained. Is difficult.

  The flame retardant polyamide fiber of the present invention contains 0.5 to 20% by weight, preferably 0.5 to 10% by weight, more preferably 0.5 to 1.9% by weight of the triazine compound having the above particle diameter. It is necessary to contain it in order to develop excellent flame retardancy.

  If the content of the triazine compound contained in the flame-retardant polyamide fiber of the present invention is less than 0.5% by weight, the required flame retardancy cannot be obtained, and conversely if it exceeds 20% by weight, it is difficult. This is not preferable because the flammability effect is saturated and the strength is rather lowered, or yarn breakage and fluff are generated and the yield of the yarn is reduced.

  Examples of the triazine compound used in the present invention include melamines and cyanuric acids, and adducts of melamines and cyanuric acids. Examples of cyanuric acids include cyanuric acid and isocyanuric acid, as well as cyanuric acid derivatives such as trimethylcyanurate, triethylcyanurate, methylcyanurate, diethylcyanurate, trinormalpropylcyanurate, regardless of enol form or keto form. Can be used. Further, the cyanuric acids may be hydrates or anhydrides. Examples of melamines include melamine, ammelide, ammelin, formoguanamine, guanylmelamine, cyanomelamine, allylguanamine, melam, melem, melamine phosphate, and the like. As an adduct of melamines and cyanuric acids, melamine cyanurate, which is an adduct of melamine and isocyanuric acid, can be exemplified, but an adduct of the melamines and cyanuric acids, preferably an equimolar adduct. The type is not limited. In addition, for example, the melamine and cyanuric acid salts obtained by mixing an aqueous solution of melamines and cyanuric acids to form a salt of both, and then filtering, contain unreacted melamines and cyanuric acids. Also good.

  Among these triazine-based compound flame retardants, cyanuric acid, isocyanuric acid, melamine, and melamicyanurate are preferably used. In particular, the use of melamine cyanurate is most preferable from the viewpoints of flame retardancy and processability.

  Moreover, the triazine type compound added to the flame retardant polyamide fiber of the present invention can further improve the flame retardancy by using various flame retardants in combination. Preferred flame retardants used in combination include alkali metal hypophosphites or earth metal hypophosphites such as sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, barium hypophosphite, hypophosphite. Examples thereof include magnesium phosphate, aluminum hypophosphite, aluminum hydroxide and magnesium hydroxide, and the amount added is usually 0.1 to 10% by weight, preferably 0.5 to 3% by weight. .

  The flame retardant polyamide fiber of the present invention preferably has a main dispersion peak temperature of 103 to 120 ° C. of loss tangent (tan δ) in dynamic viscoelasticity measurement. When the main dispersion peak temperature of tan δ is less than 103 ° C., the binding force of the molecular chain of the amorphous part in the polyamide fiber is weak, so that it is difficult to obtain the high-strength flame-retardant polyamide fiber targeted by the present invention. If the temperature is 120 ° C. or higher, yarn breaks frequently occur in the fiber manufacturing process, and stable production becomes difficult.

  In addition, the flame retardant polyamide fiber of the present invention preferably has a melting peak temperature of 227 to 280 ° C. in the DSC melting curve by the constant length constraint method. When the melting peak temperature is less than 227 ° C., the orientation of the polyamide fiber molecular chain is low, and it is difficult to obtain the high-strength flame-retardant fiber intended by the present invention. In addition, when the melting peak temperature is 280 ° C. or higher, it is necessary to apply high stress to the fiber in the fiber manufacturing process, so that the fiber tends to break and stable production becomes difficult.

  By setting the main dispersion peak temperature of tan δ and the melting peak temperature of the DSC melting curve by the constant length constraint method within the above range, it becomes easy to exert the intended strength of the present invention. As described separately, these properties can be achieved only by highly finely dispersing specific flame retardant particles and combining advanced spinning and drawing techniques.

  Furthermore, in order to prevent the weather resistance deterioration and heat resistance strength deterioration of the flame-retardant polyamide fiber of the present invention, it is preferable that the polyamide fiber further contains a copper compound in an amount of 10 to 500 ppm as a copper metal amount. When the amount of copper metal is less than 10 ppm, the effect of improving the weather resistance and heat resistance by the copper compound is low, and when the amount of copper metal exceeds 500 ppm, the copper compound becomes a foreign substance and has a risk of deteriorating the spinning performance. Yes. The amount of copper metal contained is preferably 20 to 300 ppm, more preferably 30 to 250 ppm, and the addition amount is selected depending on the use and purpose of the flame-retardant polyamide fiber. For example, when it is used as a fiber for an air bag, it may be added in an amount of about 30 to 150 ppm for the purpose of preventing thermal oxidative degradation, and when it is exposed to the outdoors such as a sheet for construction work and is intended for weather resistance, 100 A high concentration of ~ 1000 ppm is required. Examples of the copper compound include, but are not limited to, copper iodide, copper chloride, copper bromide and the like, and conventionally known inorganic and organic copper salts and simple copper metals can be used.

  Further, the polyamide fiber may further contain another heat-resistant agent in addition to the copper compound. Examples of the heat-resistant agent include amine compounds, mercapto compounds, phosphorus compounds, hindered phenol compounds, halogen compounds, alkali metal halides, alkaline earth metal halides, etc., but are not limited thereto, A combination of two or more of these may be used. Examples of the amine compound include N, N′-diphenyl-p-phenylenediamine, diallyl-p-phenylenediamine, and di-β-naphthyl-p-phenylenediamine. Examples of the mercapto compound include 2- Mercaptobenzimidazole and 2-mercaptothiazole can be exemplified, and examples of phosphorus compounds include, but are not limited to, organic and inorganic phosphoric acids such as stearyl phosphate, phosphorous acid or salts thereof. The copper compound and the heat-resistant agent may be added separately or may be added after forming a complex. As the heat-resistant agent added together with the copper compound, a mercapto compound is particularly preferable, and 2-mercaptobenzimidazole is particularly preferably combined. At this time, the addition amount of the mercapto compound is preferably 300 to 3000 ppm from the viewpoints of thermal oxidative degradation prevention and yarn-forming properties.

  Moreover, it is preferable that the flame-retardant polyamide fiber of the present invention is an original flame-retardant polyamide fiber further containing 0.1 to 1.0% by weight of an organic or inorganic pigment. By laying the polyamide fiber into a primary layer, there are advantages such as no need for dyeing, no generation waste liquid at low cost, and it is possible to obtain a flame-retardant polyamide fiber having a small load on the environment. The amount of organic or inorganic pigment added is preferably 0.02 to 0.08% by weight. When the amount of pigment added is less than 0.1% by weight, there is a possibility that fibers having the desired color tone cannot be obtained. In addition, when the addition amount exceeds 1% by weight, the pigment is deposited as a foreign substance, so that there is a possibility that it cannot be obtained with good yarn production in the fiber production process.

  Preferred pigments include zinc white, titanium oxide, bengara, titanium yellow, zinc-iron brown, titanium-cobalt green, cobalt green, cobalt blue, copper-iron black, ultramarine, calcium carbonate. Inorganic pigments such as manganese violet, carbon black, aluminum powder, bronze powder, titanium-coated mica, and copper phthalocyanine blue, copper phthalocyanine green, brominated copper phthalocyanine green, dianthraquinone red, beryllens scar And organic pigments such as retlet, beryllen red, beryllen marne, dioxane violet, isoindolinone yellow, and metal complex salt azomethine.

  As the black pigment, carbon black, iron oxide black, spinel black, manganese block, cobalt black and the like are used, and carbon black is particularly preferable.

  The flame retardant polyamide fiber containing the organic or inorganic copper compound and / or organic or inorganic pigment has remarkably excellent weather resistance, and is used for materials used outdoors, for example, an architectural net, a curing mesh, Suitable for tents, tarpaulins, tents and the like. According to the study by the present inventors, it was confirmed that the light resistance was remarkably improved when a specific flame retardant and a copper compound, more preferably a specific pigment, were used in combination. Although its action is not clear, by highly finely dispersing the flame retardant as in the present invention, the effect of blocking light on the fiber surface is high, and the distance between the copper compound and the flame retardant becomes close, It is presumed that a radical generated during photodegradation is selectively generated in the flame retardant and is caused by a synergistic effect such as being difficult to react with the polyamide molecular chain due to the effect of the copper compound.

  If the above-described conditions of the present invention are satisfied, there are no particular rules regarding various physical properties such as the elongation and the number of entanglements of the flame-retardant polyamide fiber.

The flame-retardant polyamide fiber of the present invention is woven and used as a fabric. The form of the fabric can be applied to all ordinary woven fabrics, including plain woven fabrics, oblique woven fabrics, satin woven fabrics, suede woven fabrics, russell nets,
Etc. can be used.

  Hereinafter, an example of a method for producing a flame-retardant polyamide fiber of the present invention, that is, a flame-retardant polyamide multifilament and a flame-retardant monofilament, and a flame-retardant polyamide fabric using them will be described. The manufacturing method of a fiber and a flame-retardant polyamide fabric is not restricted to this.

  As the polyamide polymer, the above-described high-viscosity polyamide polymer chip is used. Mixing of the polyamide chip with the flame retardant, the copper compound, and the original pigment can be carried out at any stage from immediately after completion of the polycondensation of the polyamide until the polyamide fiber is spun from the spinneret. For example, immediately after polycondensation is completed, in a polymerization can, flame retardant etc. is added to kneaded polyamide and kneaded, converted into chips by a conventional method, solid phase polymerization, then melt spinning with an extruder spinning machine, A method of stretching, a method of kneading a flame retardant etc. into a dried polyamide chip, melt spinning and stretching, or a master chip containing a high concentration of a flame retardant in advance, and producing the master chip and polyamide There are methods such as melt spinning and drawing while mixing chips. In order to finely disperse the flame retardant, it is preferable to mix a master chip having a flame retardant concentration of 5 to 30% in a mixing ratio of 1 to 100 with respect to the polyamide chip 100. When the concentration and mixing ratio of the flame retardant are out of the above ranges, the flame retardancy of the fiber is reduced, or secondary aggregation of the flame retardant particles is caused and it is difficult to obtain a high-strength fiber. Is likely to occur. In order to promote fine dispersion of the flame retardant, it is preferable to use a twin-screw extruder type extruder as the extruder, and a static mixer such as a static mixer is installed in the flow path of the molten polymer in the spinning machine. By incorporating, it is preferable to promote fine dispersion of the flame retardant during melting. The static mixer can be installed in any position as long as it is a molten polymer flow path, but the closer to the end of the flow path, the higher the effect of fine dispersion of the flame retardant in the fiber. More preferably, it is incorporated into a spinning pack. The number of elements of the static mixer is preferably 4 to 30 stages, more preferably 6 to 20 stages. When the number of elements is small, the effect of mixing is low. When the number is too large, the apparatus and the polymer flow path become long, which causes problems such as decomposition and deterioration of the polymer.

  The kneading and melt spinning of the polyamide chip and the flame retardant can be performed by a method common to the flame retardant polyamide multifilament and the flame retardant polyamide monofilament of the present invention.

  The melt-spun flame-retardant polyamide multifilament is cooled and solidified, then applied with an oil agent, wound around a take-up roller rotating at 300 to 2000 m / min and wound up once, or continuously in two or more stages. The film is hot-drawn and wound up by a winder. The hot stretching temperature is [glass transition point—10 to 50 ° C.] and the stretching ratio is 2.5 to 7.0 times, and the flame retardant polyamide multifilament of the present invention is produced.

  On the other hand, in the case of a flame-spun flame-retardant polyamide monofilament, after cooling and solidifying in a hot water bath at 40 to 100 ° C., preferably 60 to 80 ° C., one-stage stretching is performed in a hot water bath at 60 to 100 ° C. The film is stretched at a rate of 0.0 to 5.0 times, and then stretched in a dry heat furnace near 150 ° C. to the melting point of the polyamide in a range of a total stretch ratio of 4.0 to 7.0 times. Further, it is manufactured by performing a relaxation heat treatment at a rate of 0.8 to 1.0 times in a dry-heat furnace near 150 ° C. to the melting point.

  Thus, the flame-retardant polyamide fiber having high strength and excellent weather resistance according to the present invention is obtained.

  The polyamide fiber obtained above is woven into a fabric by a conventional method. For example, weaving on mesh sheets and curing nets, weaving on plain weaves and weaving on tarpaulins, tents, raschel nets, knotless nets, birch knot nets, safety nets, sport nets, fruit trees It can be used for nets and the like.

  Hereinafter, embodiments of the present invention will be described in more detail by way of examples. The definition and measurement method of the characteristics used in the specification text and examples are as follows.

(1) Fineness Fineness fineness was measured by the method of JIS L1017 (2002) 8.3.

(2) Strength and elongation Measured by the method of JIS L1017 (2002) 8.5.

(3) Limit oxygen index (LOI)
It was measured by the flammability test method E method (oxygen index method test) of JIS L1091 (2002) textiles. If the LOI is 25 or more, the required flame retardancy is satisfied.

(4) Boiling water shrinkage rate Measured according to JIS L1017 (2002).

(5) Main dispersion peak temperature of loss tangent (tan δ) in dynamic viscoelasticity measurement Using a DDV-II type dynamic viscoelasticity measuring device manufactured by Orientec Co., Ltd., frequency 110 Hz, heating rate 3 ° C./min The temperature at room temperature to 200 ° C. was measured, and the temperature at which the loss tangent (tan δ) showed a peak was determined.

(6) Melting peak temperature of DSC melting curve by constant length constraint method Polym. Sci. Phy. Ed. VOL. 15, 1507 “Melting of Constrained Draw Nylon 6 Yarns” was measured as follows. The weighed fibers samples, the aluminum plate 4.0X2.5X0.4Mm ^3, wound so as not slack and fixed to an aluminum plate using a thin wire that combines the sample ends, placed in an aluminum standard container measurement sample It was. For the measurement, an SSC5200 thermal analysis system manufactured by Seiko Instruments Inc. was used, and measurement was performed from 20 ° C. to 300 ° C. at a temperature rising rate of 10 ° C./min.

(7) Triazine-based compound maximum particle size and average particle size The maximum particle size and average particle size of the triazine-based compound powder can be measured using the following two methods.
A) Measurement was performed using a particle size distribution analyzer (SK Laser Micron Sizer: manufactured by Seishin Enterprise Co., Ltd.) to determine the maximum particle size and the average particle size.
B) Gold was vapor deposited on the triazine compound powder using an ion coater (IB-3 manufactured by Eiko Engineering). The prepared sample was observed using SEM (ABT-55 manufactured by Topcon Corporation), the maximum diameter of 100 particles was measured, the average was the average particle diameter, and the maximum diameter of the largest particle was the maximum particle diameter.

(8) Dispersion state of triazine compound in fiber, maximum particle diameter and average particle diameter Photograph taken at 400 to 500 times using a Nikon ECLIPSE E600W POL polarizing microscope with a thread sample cut to 5 to 10 μm Thus, the dispersion state of the triazine compound in the fiber was observed, and the maximum particle size and average particle size of the triazine compound that could be confirmed on the fiber cross section were measured. Whether the dispersed state is good or bad was judged by ○ or × depending on whether or not the secondary aggregate particle diameter having a diameter of 3 times or more of the average particle diameter of the added triazine compound can be confirmed in the fiber. .

(9) Sulfuric acid relative viscosity A polymer sample was dissolved in 98% sulfuric acid at a concentration of 1% by weight, measured at 25 ° C using an Ostwald viscometer, and determined according to the following formula.
Sulfuric acid relative viscosity (ηr) = (sample solution dropping time) / (sulfuric acid solution dropping time)
Each sample was measured twice and the average value was adopted.

(10) Weather resistance strength retention rate Using a Xenon Weather Meter manufactured by Suga Test Instruments Co., Ltd., the test conditions were a temperature of 63 ° C., water spraying, and a weather resistance test was conducted for 100 hours as a black panel method. The ratio (%) of the strength of the sample after the test to the strength (100%) of the sample before the test was determined.

(11) LOI measurement after weather resistance test Nets left outdoors for 800 days were measured by the above-mentioned critical oxygen index measurement method.

[Example 1]
Weighed a nylon polymer with a relative viscosity of sulfuric acid of 3.8 and a nylon 6 master polymer to which 10% by weight of melamine cyanurate powder with an average particle size of 1.2μm and a maximum particle size of 3.1μm was added and 0.5% by weight of carbon black. While continuously metered in a vessel, the mixture was continuously fed to a twin screw extruder type extruder at 285 ° C. at a ratio of 7: 3 and melted continuously. 100 ppm of copper iodide was added to each polymer.

  The molten polymer is kneaded with an eight-stage static mixer through a pipe at 285 ° C., weighed with a gear pump so that the total fineness becomes 1700 dtex, then led to a spinning pack at 285 ° C., and a 30 micron cut filter is installed in the pack. It was allowed to pass through and was extruded from a die having 200 single holes having a hole diameter of 0.5 mm and a hole length of 1.1 mm.

  After passing through a heated cylinder having a length of 20 cm and an ambient temperature of 310 ° C. provided with a spun yarn under the die, solidified by blowing cold air at 30 ° C. at a rate of 40 m / min using a uniflow type chimney, Oil was applied with an oil roller. The yarn provided with the oil was wound up by a first roller (non-heated) having a surface speed of 475 m / min, and then subjected to a stretching process continuously.

  The second roller (55 ° C.) with a speed of 500 m / min, a third roller (90 ° C.) with a speed of 1375 m / min, a fourth roller (155 ° C.) with a speed of 1800 m / min, a speed of 2250 m The nylon 6 multifilament with a total fineness of 1700 dtex was obtained by continuously applying to a fifth roller (195 ° C.) / Min and a sixth roller (130 ° C.) at a speed of 2150 m / min. The characteristics of the obtained nylon 6 multifilament are shown in Table 1.

  The obtained nylon 6 multifilament was netted by a Russell knitting machine so that the total fineness of the net yarn was 13600 dtex and the length of one side of the mesh was 15 mm. The obtained net was subjected to a treatment for 1 minute at a heat setting temperature of 180 ° C. using a tenter. The critical oxygen index of the obtained net and the critical oxygen index after the weather resistance test were measured, and the results are shown in Table 1.

[Example 2]
The polymer was extruded from the die with the same apparatus as in Example 1 except that the hole diameter of the die was 1.5 mm, the hole length was 1.8 mm, and the heating cylinder was not used. The obtained yarn was continuously cooled in water at 20 ° C. and taken up by a take-up roll at a speed of 10 m / min, then continuously stretched 3.8 times in a warm water bath at 95 ° C. and subsequently 180 ° C. The film was stretched 1.6 times in polyethylene glycol heated and then stretched at a stretch ratio of 0.95 times in a warm water bath at 90 ° C. to obtain a nylon 6 monofilament having a total fineness of 2000 dtex. The properties of the obtained nylon 6 monofilament are shown in Table 1.

  The obtained nylon 6 monofilament was netted by a Russell knitting machine so that the total fineness of the net yarn was 16000 dtex and the length of one side of the net was 15 mm. The obtained net was subjected to a treatment for 1 minute at a heat setting temperature of 180 ° C. using a tenter. The critical oxygen index of the obtained net and the critical oxygen index after the weather resistance test were measured, and the results are shown in Table 1.

[Example 3]
Nylon 6 polymer and nylon 6 master polymer were mixed at a ratio of 2: 8 and subjected to the spinning process, melamine cyanurate having an average particle size of 2.0 μm and a maximum particle size of 4.5 μm was added, and the number of pores Was performed in the same manner as in Example 1 except that 20 caps were used.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

[Example 4]
Nylon 6 polymer and nylon 6 master polymer were mixed at a ratio of 9: 1 and subjected to the spinning process, melamine cyanurate having an average particle size of 0.7 μm and a maximum particle size of 2.5 μm was added, carbon black The same procedure as in Example 1 was performed except that 0.7 wt% was added, 20 ppm of copper iodide was added to each polymer, and a die having 360 holes was used.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

[Example 5]
Nylon 6 master polymer and nylon 6 master polymer added with 20% by weight of melamine cyanurate powder with an average particle size of 0.7μm and maximum particle size of 2.5μm, and 0.2% by weight of carbon black were mixed at a ratio of 1: 9. And 300 ppm of copper iodide was added to each polymer, and the respective roller speeds were set to 560 m / min for the first roller, 590 m / min for the second roller, 1406 m / min for the third roller, The same operation as in Example 1 was performed except that the fourth roller was changed to 1830 m / min, the fifth roller was 2250 m / min, and the sixth roller was 2150 m / min.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

[Example 6]
Nylon 6 polymer and nylon 6 master polymer were mixed at a ratio of 2: 8 and subjected to the spinning process, melamine cyanurate having an average particle size of 2.0 μm and a maximum particle size of 4.5 μm was added, and carbon black The addition of 0.2% by weight, the addition of 200 ppm of copper iodide to each polymer, the production of monofilaments with a total fineness of 7000 dtex, and the obtained nylon 6 monofilament with a Russell knitting machine The same procedure as in Example 2 was performed except that the net was made to have a length of 56000 dtex and a length of one side of the mesh of 15 mm.

  The properties of the obtained nylon 6 monofilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 1]
The same procedure as in Example 1 was performed except that a single-screw extruder type extruder was used without using a master chip. The net obtained was 40% flame retardant (Daikyo Chemical Bigol NA-7) 40%, water 58.8%, hard finish (Sumitomo Chemical Sumitex Resin M-3) 1%, catalyst (Sumitomo Chemical Sumitex Accelerator ACX) ) Dip with a 0.2% solution to a pickup of 70% and dry at 140 ° C. for 2 minutes.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 2]
The same procedure as in Example 2 was performed except that a single-screw extruder type extruder was used without using a master chip. The net obtained was 40% flame retardant (Daikyo Chemical Bigol NA-7), 58.8% water, hard finish (Sumitomo Chemical Sumitex Resin M-3) 1%, catalyst (Sumitomo Chemical Sumitex Accelerator ACX) ) Dip with a 0.2% solution to a pickup of 70% and dry at 140 ° C. for 2 minutes.

  The properties of the obtained nylon 6 monofilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 3]
Nylon 6 polymer and nylon 6 master polymer were mixed at a ratio of 2: 8 and subjected to the spinning process, melamine cyanurate having an average particle size of 2.5 μm and a maximum particle size of 5.2 μm was added, and each roller Other than changing the speed to the first roller 660 m / min, the second roller 695 m / min, the third roller 1470 m / min, the fourth roller 1850 m / min, the fifth roller 2250 m / min, and the sixth roller 2150 m / min The same procedure as in Example 1 was performed.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 4]
Nylon 6 polymer and nylon 6 master polymer were mixed at a ratio of 2: 8 and subjected to the spinning process, melamine cyanurate having an average particle size of 2.5 μm and a maximum particle size of 5.2 μm was added, continuously The film was stretched 3.4 times in a 95 ° C warm water bath and subsequently stretched 1.1 times in polyethylene glycol heated to 180 ° C and then stretched in a 90 ° C warm water bath at a stretch ratio of 0.9 times. To obtain a nylon 6 monofilament with a total fiber length of 360 dtex, and to net the obtained nylon 6 monofilament with a Russell knitting machine so that the total fineness of the net yarn is 2880 dtex and the length of one side of the mesh is 15 mm. Except for this, the same procedure as in Example 2 was performed.

  The properties of the obtained nylon 6 monofilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 5]
Each roller speed was changed to the first roller 690 m / min, the second roller 725 m / min, the third roller 1470 m / min, the fourth roller 1850 m / min, the fifth roller 2250 m / min, and the sixth roller 2150 m / min. , And the same procedure as in Example 1 except that a multifilament having a total fineness of 240 dtex was obtained.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 6]
Continuously stretched 3.0 times in a 95 ° C hot water bath and subsequently stretched 1.0 times in polyethylene glycol heated to 180 ° C and subsequently stretched 0.9 times in a 90 ° C hot water bath A nylon 6 monofilament with a total fiber of 82000 dtex was obtained by stretching the ratio, and the obtained nylon 6 monofilament was manufactured with a Russell knitting machine so that the total fineness of the net yarn was 656000 dtex and the length of one side of the mesh was 15 mm. The procedure was the same as in Example 2 except that the mesh was used.

  The properties of the obtained nylon 6 monofilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 7]
Without using a nylon 6 polymer, only a nylon 6 master polymer to which 24% by weight of melamine cyanurate powder having an average particle size of 3.2 μm and a maximum particle size of 6.1 μm was added and 0.5% by weight of carbon black was used. The use of a single-screw extruder type extruder, the use of a nozzle with 12 holes, and the speeds of the respective rollers were as follows: first roller 660 m / min, second roller 695 m / min, third roller 1470 m / min The same procedure as in Example 1 was performed except that the fourth roller was changed to 1850 m / min, the fifth roller was 2250 m / min, and the sixth roller was 2150 m / min.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

[Comparative Example 8]
Nylon 6 polymer and nylon 6 master polymer were mixed at a ratio of 9.7: 0.3 and subjected to the spinning process, and melamine cyanurate powder having an average particle size of 3.2 μm and a maximum particle size of 6.1 μm was added. And the roller speeds of the first roller 660 m / min, the second roller 695 m / min, the third roller 1470 m / min, the fourth roller 1850 m / min, the fifth roller 2250 m / min, and the sixth roller 2150 m / min. The procedure was the same as in Example 1 except that the change was made.

  The properties of the obtained nylon 6 multifilament and net were evaluated, and the results are shown in Table 1.

  As is clear from Table 1, the nets of Examples 1 to 6 that satisfy the conditions of the present invention are flame retardant polyamide fibers and fabrics that are excellent in flame retardancy after netting without post-processing. The flame retardant performance hardly changes even after the deterioration test.

  However, as shown in Comparative Examples 1 and 2, the fabric imparted with flame retardancy by post-processing is a polyamide fiber fabric having a high LOI immediately after the flame-retardant processing and excellent flame retardancy, but is exposed to the outdoors for a long time. When fired, the flame retardancy was severely reduced.

  As in Comparative Examples 3 and 4, when the average particle size and the maximum particle size of the triazine compound exceeded the provisions of the present invention, it was possible to collect polyamide filament fibers, but in the polyamide fiber manufacturing process, fluff Occurrence occurred frequently, and fibers could not be collected stably.

  As in Comparative Example 5, when the single yarn fineness is less than that of the present invention, fluff and yarn breakage frequently occur in the polyamide multifilament manufacturing process, and it is not possible to obtain a polyamide multifilament fiber worthy of practical use. It was.

  When the total fineness exceeded the provisions of the present invention as in Comparative Example 6, fluff and thread breakage occurred frequently in the polyamide monofilament manufacturing process, and polyamide monofilament fibers worthy of practical use could not be obtained.

  As in Comparative Example 7, when the triazine compound content exceeds the definition of the present invention, and when the single yarn fineness exceeds the definition of the present invention, the polyamide multifilament can be collected, but the polyamide multifilament In the production process, fluff frequently occurred and fibers could not be collected stably.

  As in Comparative Example 8, when the content of the triazine-based compound is less than the provisions of the present invention, the required flame retardancy cannot be obtained, and the polyamide multifilament having flame retardance worthy of practical use The fiber could not be obtained.

  The flame retardant polyamide fiber and flame retardant fabric of the present invention are not only excellent in physical properties such as strength and abrasion resistance, but also in chemical properties such as flame retardancy, weather resistance and chemical resistance, and are also put into practical use. Because it has the characteristic that flame retardant performance deterioration is extremely small during the operation, it is effectively used as a tire cord, airbag, tent, tarpaulin, belt, rope, land net, fishing net, etc. can do.

Claims (10)

Polyamide multifilament having a single yarn fineness of 1.5 to 100 dtex, a strength of 4.5 to 9.0 cN / dtex, and a boiling water shrinkage of 5 to 15%, and an average particle size of 0.1 to 2.3 μm, A flame-retardant polyamide fiber comprising 0.5 to 20% by weight of a triazine compound having a maximum particle size of less than 5 μm. A triazine-based compound having a fineness of 80 to 80,000 dtex and a strength of 4.5 to 9.0 cN / dtex, an average particle size of 0.1 to 2.3 μm, and a maximum particle size of less than 5 μm is 0.00. A flame-retardant polyamide fiber containing 5 to 20% by weight. The flame retardant polyamide fiber according to claim 1 or 2, wherein a main dispersion peak temperature of loss tangent (tan δ) in dynamic viscoelasticity measurement is 103 to 120 ° C. The flame retardant polyamide fiber according to any one of claims 1 to 3, wherein a melting peak temperature of a DSC melting curve in a constant length constraint method is 227 to 280 ° C. The flame retardant polyamide fiber according to any one of claims 1 to 4, wherein the triazine compound is contained in an amount of 0.5 to 10% by weight. The flame retardant polyamide fiber according to any one of claims 1 to 5, comprising 0.5 to 1.9% by weight of the triazine compound. The flame retardant polyamide fiber according to any one of claims 1 to 6, wherein the triazine-based compound is melamine cyanurate. The flame retardant polyamide fiber according to any one of claims 1 to 7, wherein the flame retardant polyamide fiber further contains a copper compound in an amount of 10 to 500 ppm as a copper metal amount. The flame retardant polyamide fiber according to any one of claims 1 to 8, wherein the flame retardant polyamide fiber further contains 0.1 to 1% by weight of an organic or inorganic pigment. A flame-retardant fabric comprising the flame-retardant polyamide fiber according to any one of claims 1 to 9.