阅读说明：本技术 熔融各向异性芳香族聚酯复丝 (Melt anisotropic aromatic polyester multifilament yarn ) 是由 荻野祐二 中村卓志 研井孝太 于 2019-03-01 设计创作，主要内容包括：本发明提供耐磨损性优异的熔融各向异性芳香族聚酯复丝。所述熔融各向异性芳香族聚酯复丝是单丝纤度为10～80dtex的熔融各向异性芳香族聚酯复丝,其中,在复丝的纤维表面附着有相对于复丝重量为3～10重量％的二甲基硅酮类整理剂,所述二甲基硅酮类整理剂包含重均分子量为15000～40000的二甲基硅酮类化合物。(The invention provides a melt anisotropic aromatic polyester multifilament yarn having excellent abrasion resistance. The melt anisotropic aromatic polyester multifilament is a melt anisotropic aromatic polyester multifilament having a single-filament fineness of 10 to 80dtex, wherein a dimethylsilone finishing agent is attached to the surface of the fiber of the multifilament in an amount of 3 to 10 wt% based on the weight of the multifilament, and the dimethylsilone finishing agent contains a dimethylsilone compound having a weight-average molecular weight of 15000 to 40000.)

1. A melt anisotropic aromatic polyester multifilament is a melt anisotropic aromatic polyester multifilament having a single-filament fineness of 10 to 80dtex, wherein a dimethylsilone finishing agent is attached to the surface of the multifilament at a weight ratio of 3 to 10 wt% relative to the weight of the multifilament, and the dimethylsilone finishing agent contains a dimethylsilone compound having a weight-average molecular weight of 15000 to 40000.

2. The melt-anisotropic aromatic polyester multifilament yarn according to claim 1, which has a strength of 20cN/dtex or more.

3. The melt-anisotropic aromatic polyester multifilament according to claim 1 or 2, wherein the average fiber diameter of the monofilaments is 30 to 85 μm.

4. The melt anisotropic aromatic polyester multifilament yarn according to any one of claims 1 to 3, wherein the viscosity of the dimethylsilicone finishing agent is 300 to 3000mm²/s。

5. The melt anisotropic aromatic polyester multifilament according to any one of claims 1 to 4, wherein the melt anisotropic aromatic polyester multifilament has a fiber-to-fiber dynamic friction coefficient of 0.080 to 0.150.

6. A fiber structure at least a part of which comprises the melt anisotropic aromatic polyester multifilament according to any one of claims 1 to 5.

Technical Field

The present invention relates to a melt anisotropic aromatic polyester multifilament yarn having excellent abrasion resistance.

Prior Art

It is known that melt anisotropic aromatic polyesters are polymers composed of rigid molecular chains, and it is possible to obtain the highest strength and elastic modulus among fibers obtained by melt spinning by highly orienting the molecular chains in the fiber axis direction in melt spinning and further performing heat treatment (solid phase polymerization). It is also known that melt anisotropic aromatic polyester fibers can increase the molecular weight and increase the melting point by solid-phase polymerization, and therefore can improve the heat resistance and dimensional stability. Thus, the melt anisotropic aromatic polyester fiber can exhibit high strength, high elastic modulus, excellent heat resistance, and excellent dimensional stability by solid-phase polymerization.

In addition to the above characteristics, the melt anisotropic aromatic polyester fiber has high chemical resistance and low moisture absorption characteristics, and thus is useful for control cables, tension members (optical fibers, electric wires, head cones (head cone), etc.), electric wire reinforcements for various electric appliances, heater core wires, canvases, ropes, protective gloves, reinforcements for plastics, etc., and is particularly excellent in abrasion resistance, and thus is used for mountain climbing ropes, land nets (safety nets, purse nets for golf ranges, etc.), lifelines, fishing lines, fishing nets, hooks, slings, etc.

Among them, patent document 1 (jp 2013-133576 a) describes that by melt-spinning a melt anisotropic aromatic polyester containing a specific amount of a metal soap, unevenness occurring between single fibers of a multifilament can be suppressed, a multifilament having high strength, high elastic modulus, excellent heat resistance, excellent dimensional stability, less burrs, and excellent high-order process passability can be obtained, and a fiber suitable for use in ropes, fishing nets, and slings can be obtained.

Disclosure of Invention

Problems to be solved by the invention

However, in patent document 1, since the oil agent is applied before the solid-phase polymerization treatment in the production method thereof, the oil agent is decomposed in the solid-phase polymerization treatment depending on the kind of the oil agent, and there is a possibility that burrs are generated in the winding step after the solid-phase polymerization treatment. Even when the oil agent is not decomposed, the oil agent may move due to evaporation, heat convection, or the like of the oil-containing component caused by the influence of heat applied in the solid-phase polymerization treatment, and thus the adhesion distribution of the oil agent after the solid-phase polymerization treatment may become uneven. Therefore, the obtained melt anisotropic aromatic polyester multifilament yarn has insufficient abrasion resistance.

The present invention is an invention to solve the problems of the prior art and to provide a melt anisotropic aromatic polyester multifilament having excellent abrasion resistance.

Means for solving the problems

The present inventors have conducted various studies to improve the abrasion resistance of a melt anisotropic aromatic polyester multifilament, and as a result, have unexpectedly found that when a specific amount of a dimethylsilicone finishing agent containing a dimethylsilicone compound having a specific molecular weight is attached to the surface of a fiber while the single-yarn fineness is a specific coarse fineness, the abrasion resistance of a melt anisotropic aromatic polyester multifilament can be greatly improved while maintaining the strength of the melt anisotropic aromatic polyester multifilament as compared with a conventional multifilament having a fine single yarn, and have completed the present invention.

That is, the present invention can be configured as follows.

[ means 1]

A melt anisotropic aromatic polyester multifilament having a single-filament fineness of 10 to 80dtex (preferably 10 to 60dtex, more preferably 15 to 50dtex), wherein a dimethylsilone finishing agent having a weight-average molecular weight of 15000 to 40000 (preferably 18000 to 35000, more preferably 20000 to 30000) is attached to the surface of the fiber of the multifilament in an amount of 3 to 10 wt% (preferably 3 to 8 wt%, more preferably 4 to 6 wt%) based on the weight of the multifilament.

[ means 2]

The melt anisotropic aromatic polyester multifilament according to embodiment 1 has a strength of 20cN/dtex or more (preferably 21cN/dtex or more, and more preferably 23cN/dtex or more).

[ means 3]

The melt-anisotropic aromatic polyester multifilament according to mode 1 or 2, wherein the average fiber diameter of the monofilaments is 30 to 85 μm (preferably 33 to 80 μm, more preferably 35 to 70 μm).

[ means 4]

The melt-anisotropic aromatic polyester multifilament according to any one of aspects 1 to 3, wherein the viscosity of the dimethylsilicone finishing agent is 300 to 3000mm²(preferably 300 to 2000 mm)²A concentration of 300 to 1500mm is more preferable²/s)。

[ means 5]

The melt-anisotropic aromatic polyester multifilament according to any one of embodiments 1 to 4, wherein a fiber-to-fiber dynamic friction coefficient of the melt-anisotropic aromatic polyester multifilament is 0.080 to 0.150 (preferably 0.085 to 0.140, and more preferably 0.090 to 0.130).

[ means 6]

A fiber structure at least a part of which comprises the melt anisotropic aromatic polyester multifilament according to any one of embodiments 1 to 5.

In the present invention, the melt anisotropic aromatic polyester multifilament yarn is a concept including a dimethylsilone-based finish. Thus, for convenience, when simply referred to as multifilament, refers to the state of individual multifilament yarns without a dimethyl silicone based finish; when it is referred to as a melt anisotropic aromatic polyester multifilament, it means a multifilament to which a dimethylsilicone finish is attached.

It is to be noted that any combination of at least 2 constituent elements disclosed in the claims and/or the specification is also included in the present invention. In particular, any combination of 2 or more claims described in the claims is also included in the present invention.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a melt anisotropic aromatic polyester multifilament excellent in abrasion resistance can be provided. The melt anisotropic aromatic polyester multifilament of the present invention can be suitably used for a rope, an electric wire, and particularly for a fiber structure such as a sling.

Detailed Description

The present invention will be described in detail below.

(melt anisotropic aromatic polyester)

The multifilament yarn formed of the melt anisotropic aromatic polyester can be obtained by melt spinning the melt anisotropic aromatic polyester. The melt anisotropic aromatic polyester is composed of repeating structural units derived from, for example, an aromatic diol, an aromatic dicarboxylic acid, an aromatic hydroxycarboxylic acid, etc., and the chemical structure of the structural units derived from an aromatic diol, an aromatic dicarboxylic acid, or an aromatic hydroxycarboxylic acid is not particularly limited as long as the effect of the present invention is not impaired. The melt anisotropic aromatic polyester may contain a structural unit derived from an aromatic diamine, an aromatic hydroxylamine, or an aromatic aminocarboxylic acid within a range not to impair the effects of the present invention. For example, examples shown in table 1 can be cited as preferable constitutional units.

[ Table 1]

(wherein X in the formula is selected from the following structures)

(wherein m is 0 to 2, and Y is selected from hydrogen, halogen atom, alkyl group, aryl group, aralkyl group, and alkoxy group

Substituents of radicals, aryloxy radicals, aralkyloxy radicals)

In the structural units in table 1, m is an integer of 0 to 2, and Y in the formula, within the range of 1 to the maximum number of substitutable substituents, may each independently include a hydrogen atom, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, etc.), an alkoxy group (e.g., a methoxy group, an ethoxy group, an isopropoxy group, a n-butoxy group, etc.), an aryl group (e.g., a phenyl group, a naphthyl group, etc.), an aralkyl group (e.g., a benzyl group, a phenethyl group (phenylethyl), etc.), an aryloxy group (e..

More preferred examples of the structural units include those described in examples (1) to (18) shown in tables 2, 3 and 4 below. When the structural unit in the formula is a structural unit capable of expressing a plurality of structures, two or more of such structural units may be used in combination as a structural unit constituting a polymer.

[ Table 2]

[ Table 3]

[ Table 4]

In the structural units in tables 2, 3 and 4, n is an integer of 1 or 2, each structural unit n-1, n-2 may be present alone or in combination, and Y is₁And Y₂Each independently represents a hydrogen atom, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, etc.), an alkoxy group (e.g., a methoxy group, an ethoxy group, an isopropoxy group, a n-butoxy group, etc.), an aryl group (e.g., a phenyl group, a naphthyl group, etc.), an aralkyl group (e.g., a benzyl group (phenylmethyl group), a phenethyl group (phenylethyl group), etc.), an aryloxy group (. Among them, a hydrogen atom, a chlorine atom, a bromine atom or a methyl group is preferable.

Examples of Z include a substituent represented by the following formula.

[ chemical formula 1]

The melt anisotropic aromatic polyester may preferably have a naphthalene skeleton as a combination of structural units. Particularly, both the structural unit (a) derived from hydroxybenzoic acid and the structural unit (B) derived from hydroxynaphthoic acid are preferably contained. For example, the structural unit (a) includes the following formula (a); examples of the structural unit (B) include the following formula (B); the ratio of the structural unit (A) to the structural unit (B) may be preferably in the range of 9/1 to 1/1, more preferably 7/1 to 1/1, and still more preferably 5/1 to 1/1, from the viewpoint of improving melt moldability.

[ chemical formula 2]

[ chemical formula 3]

The total of the structural unit of (a) and the structural unit of (B) may be, for example, 65 mol% or more, more preferably 70 mol% or more, and still more preferably 80 mol% or more, based on the total structural units. Among the polymers, a melt anisotropic aromatic polyester having a structural unit of (B) of 4 to 45 mol% is particularly preferable.

The melting point (hereinafter, also referred to as Mp) of the melt anisotropic aromatic polyester preferably used in the present invention is preferably in the range of 250 to 360 ℃, more preferably 260 to 320 ℃. The melting point is a main absorption peak temperature measured by a differential scanning calorimeter (DSC; TA3000, manufactured by METTLER) in accordance with the test method JIS K7121. Specifically, in the DSC apparatus, 10 to 20mg of a sample was weighed and sealed in an aluminum pan, and then nitrogen gas as a carrier gas was introduced at a flow rate of 100 cc/min, and an endothermic peak at a temperature rise of 20 ℃/min was measured. Depending on the type of polymer, when no clear peak appears in 1st run in DSC measurement, the temperature is raised at a rate of 50 ℃ per minute to a temperature 50 ℃ higher than the expected flow temperature, and after complete melting for 3 minutes at that temperature, the temperature is lowered at a rate of 80 ℃ per minute to 50 ℃, and then the endothermic peak is measured at a rate of 20 ℃ per minute.

The melt anisotropic aromatic polyester may contain a thermoplastic polymer such as polyethylene terephthalate, modified polyethylene terephthalate, polyolefin, polycarbonate, polyamide, polyphenylene sulfide, polyether ether ketone, or fluororesin, as long as the effects of the present invention are not impaired. In addition, various additives such as inorganic substances such as titanium oxide, kaolin, silica, and barium oxide, colorants such as carbon black, dyes, and pigments, antioxidants, ultraviolet absorbers, and light stabilizers may be contained.

(melt anisotropic aromatic polyester multifilament yarn)

From the viewpoint of high strength and improved abrasion resistance, it is important that the melt anisotropic aromatic polyester multifilament of the present invention has a single-fiber fineness of 10 to 80 dtex. In the present invention, it has been unexpectedly found that the abrasion resistance of the melt anisotropic aromatic polyester multifilament can be greatly improved by setting the fineness of the single yarn to a specific range. When the conditions for fixing the finishing agent were observed and only the effect of the fineness was observed, the abrasion resistance was greatly improved when the single fiber fineness was 10dtex or more, and thereafter, although the larger the single fiber fineness was, the more the abrasion resistance was improved, the abrasion resistance tended to be lowered when the single fiber fineness was too large. The reason why the abrasion resistance can be improved by the single-fiber fineness of 10dtex or more is not clear. On the other hand, the tensile strength tends to decrease as the fineness of the single yarn increases, and when the fineness is too large, the effect of improving the abrasion resistance is offset or the abrasion resistance tends to decrease due to the decrease in the tensile strength. When the single-yarn fineness exceeds 80dtex, bundling properties as a multifilament are further reduced, and for example, when the multifilament is wound in a square end shape in a spinning step or a winding step, the multifilament is easily unraveled at the end face. The single fiber fineness is more preferably 10 to 60dtex, and still more preferably 15 to 50 dtex.

The average fiber diameter of the filaments of the melt anisotropic aromatic polyester multifilament yarn of the present invention may be 30 to 85 μm, preferably 33 to 80 μm, and more preferably 35 to 70 μm, from the viewpoint of high strength and improved abrasion resistance. The average fiber diameter of the monofilament is a value measured by the method described in the examples described later, and represents a value calculated from the fineness of the monofilament when the cross section is assumed to be a perfect circle. The specific gravity used for the calculation can be measured by a known method.

The number of filaments of the melt anisotropic aromatic polyester multifilament yarn of the present invention is preferably 5 to 5000. If the number of filaments is too small, the multifilament cannot withstand the winding tension and yarn breakage may easily occur. In addition, when the number of filaments is too large, the multifilament may become too thick and may be difficult to wind normally by a winder.

The total fineness of the multifilament is preferably 50 to 400000 dtex. When the total fiber is too small, it cannot withstand the tension in the process passage and yarn breakage may occur. When the total fineness is too large, the multifilament becomes too thick to be wound normally by a winder.

In the melt anisotropic aromatic polyester multifilament of the present invention, it is important that a specific dimethylsilicone finishing agent is attached to the surface of the fiber in an amount of 3 to 10 wt% based on the weight of the multifilament. More preferably 3 to 8 wt%, and still more preferably 4 to 6 wt%. If the amount of finish deposited is less than 3 wt%, the entire fiber surface is difficult to coat with the finish, uneven deposition is likely to occur, and excellent abrasion resistance may not be obtained. On the other hand, if it exceeds 10% by weight, the finishing agent is deposited on the surface of the guide or the roller, and the process passability is deteriorated, the workability of raising the product is deteriorated, and the productivity may be deteriorated.

The reason why the abrasion resistance of the melt anisotropic aromatic polyester multifilament yarn of the present invention can be significantly improved by providing a specific dimethylsilicone finish as a finish is not yet determined, but it is considered that one of the reasons is that the dimethylsilicone finish is attached to the outer surface of the multifilament yarn so as to form a film, and the dimethylsilicone finish is distributed so as to coat the filaments of the multifilament yarn and to collect and bundle the filaments. In this case, the dimethylsilicone finishing agent enters so as to coat the filaments, and abrasion between the filaments is suppressed, thereby improving abrasion resistance.

The strength of the melt anisotropic aromatic polyester multifilament yarn of the present invention may be 20 cN/dtex. If the strength is too low, the strength per 1 filament is low, and therefore, for example, in the case of a sling, the fineness and the number of filaments are increased to satisfy the required strength, and the resulting sling may become thick and heavy. However, if the strength is 20cN/dtex or more, even if the fineness or the number of filaments is small, a multifilament satisfying the strength required for a sling application, for example, can be obtained, and the sling can be made thinner and lighter. More preferably 21cN/dtex or more, and further preferably 23cN/dtex or more. The upper limit is not particularly limited, but is preferably 40cN/dtex or less, and more preferably 35cN/dtex or less. The strength represents tensile strength, and is a value measured by a method described in examples described later.

The melt anisotropic aromatic polyester multifilament of the present invention has a fiber-fiber dynamic friction coefficient in a state where a finish is adhered, as measured by a measurement method described later, of preferably 0.080 to 0.150, more preferably 0.085 to 0.140, and further preferably 0.090 to 0.130, from the viewpoint of improving abrasion resistance.

(Dimethylsilicone-type finishing agent)

As a finishing agent used for the melt anisotropic aromatic polyester multifilament yarn of the present invention, it is important to use a dimethyl silicone-based finishing agent in order to improve abrasion resistance. The dimethylsilicone finishing agent contains a dimethylsilicone compound as a main component, and the dimethylsilicone compound is not particularly limited as long as it has a dimethylpolysiloxane structure in its chemical structure, and a part or a terminal of a side chain may be modified to a functional group other than a methyl group. The dimethylsilicone finishing agent may contain various additives such as a surfactant, a penetrant, an antistatic agent, and an antibacterial agent in addition to the dimethylsilicone compound. The important weight average molecular weight of the dimethylsilone compound is 15000 to 40000, more preferably 18000 to 35000, and still more preferably 20000 to 30000. If the weight average molecular weight is less than 15000, sufficient film strength may not be obtained on the fiber surface, and abrasion resistance may be insufficient. In addition, if the weight average molecular weight exceeds 40000, the finishing agent viscosity becomes too high, and it may be difficult to uniformly apply the finishing agent to the fiber surface. The weight average molecular weight of the dimethylsilicone compound can be determined as a weight average molecular weight of polystyrene in terms of Gel Permeation Chromatography (GPC).

In addition, the viscosity of the dimethyl silicone finishing agent is preferably 300-3000 mm²And s. When the viscosity is too low, the coefficient of dynamic friction between fibers decreases, and the finish agent is easily applied uniformly to the fiber surface, but the finish agent is easily peeled off from the fiber surface by the friction between fibers, and the abrasion resistance may be deteriorated. When the viscosity is too high, the coefficient of dynamic friction increases, and therefore the finish cannot conform to the friction between fibers, and the abrasion of the monofilament cannot be reduced, which may deteriorate the abrasion resistance. Can be more preferably 300 to 2000mm²More preferably 300 to 1500mm in terms of a mass fraction of the total mass fraction²And s. Here, the viscosity means a dynamic viscosity, and can be measured, for example, by an ubbrunett viscometer in accordance with JIS Z8803.

The method for producing a melt anisotropic aromatic polyester multifilament yarn of the present invention may comprise at least: the method for producing the yarn comprises a step of forming a spun yarn composed of a melt anisotropic aromatic polyester, a step of heat-treating the spun yarn, and a step of applying a specific dimethylsilicone finishing agent to the heat-treated multifilament in an amount of 3 to 10 wt% based on the weight of the multifilament.

The method for forming fibers from spun yarn made of melt anisotropic aromatic polyester is not limited, and fibers obtained by melt spinning can be generally used. The melt spinning can be carried out by a known or conventional method, and for example, it can be obtained by melting a fiber-forming resin for obtaining a liquid crystal polyester fiber in an extruder and then ejecting the molten resin from a nozzle at a predetermined spinning temperature.

The melt anisotropic aromatic polyester fiber of the present invention can further improve the strength and elastic modulus of the fiber by heat-treating the spun yarn. The heat treatment is preferably carried out at a temperature of (Mp-80) to (Mp) ° c. For example, the heat treatment temperature may be more preferably (Mp-50) to (Mp) ° C, and still more preferably (Mp-30) to (Mp-1) ° C. Since the melting point of the melt anisotropic aromatic polyester fiber of the present invention increases as the heat treatment temperature increases, it is preferable to perform heat treatment while increasing the temperature stepwise as a heat treatment method. As the heat treatment gas atmosphere, an inert gas such as nitrogen or argon, an active gas such as air, or a gas atmosphere in which these gases are combined is preferably used. The heat treatment may be performed under reduced pressure.

The heat treatment can be performed in a twisted yarn form, a tow form, or a form in which a yarn is continuously formed between rolls even when the metallic bobbin is wound into a package form, and is preferably performed in a package form in view of simplifying the facility and improving productivity.

The method of applying the above-mentioned dimethylsilicone finishing agent to the heat-treated multifilaments in an amount of 3 to 10 wt% based on the weight of the multifilaments is not particularly limited as long as a specific amount of the dimethylsilicone finishing agent can be applied to the multifilaments, and examples thereof include known application methods such as impregnation treatment, discharge treatment, coating treatment, and treatment with a dipping press liquid. From the viewpoint of adjusting the amount of adhesion, a discharge treatment, a coating treatment, a treatment of immersing in a pressing liquid, and the like, which are applied to the running yarn at the time of winding the multifilament after the heat treatment, and the like, are preferable. By applying a dimethylsilicone finish to the multifilaments after the heat treatment, decomposition and movement of the dimethylsilicone finish due to the heat treatment can be suppressed, and thus the multifilaments can be attached to the surface thereof so as to form a coating film.

The form in which the dimethylsilicone finish is applied is not particularly limited as long as a specific amount of the dimethylsilicone finish can be applied to the multifilament, and may be a stock solution of the dimethylsilicone compound or a diluted solution (e.g., an emulsion). The amount of the dimethylsilicone finish added to the weight of the multifilament yarn does not include a solvent for dilution.

The melt anisotropic aromatic polyester multifilament yarn of the present invention can be suitably used for various fiber structures. The fiber structure herein refers to a rope, net, fishing net, sling, tension member, etc. made of the fiber of the present invention. The fiber structure may be composed of the melt anisotropic aromatic polyester multifilament alone, or may include other components within a range not impairing the effects of the present invention. The fiber structure is preferably used for a rope or a sling, which is particularly required to have high abrasion resistance due to a high load applied to the fiber structure in use.