JP6420141B2 - Conductive yarn and method for producing the same - Google Patents

Description

  The present invention relates to a yarn excellent in static elimination performance. More specifically, the present invention relates to a yarn obtained from a multi-layer bonded composite fiber that can suppress dust generation during actual use, has excellent wiping performance, and can maintain conductive performance for a long period of time.

  In precision electronic equipment parts such as hard disks and magnetic tapes, and the body of automobiles, the presence or absence of dirt such as oil film or dust on the surface of these parts has a significant effect on quality and performance. A wiping process is provided to clean the product.

  Conventionally, as a wiping means in such a wiping process, for example, it has been proposed to use a wiping tape obtained by slitting a fabric using ultrafine fibers (for example, see Patent Document 1). Since the wiping tape made of a fabric using ultrafine fibers has less wiping residue on the surface to be treated compared to the wiping tape usually made of fine fibers, it can exhibit higher wiping performance. However, there is a problem that dust and the like are reattached by static electricity generated by friction during wiping.

  In order to prevent these, some antistatic treatment can be obtained by applying antistatic processing agent, but stable wiping because there are problems in the environment such as low humidity and durability including washing. Sex was not obtained.

  Furthermore, Patent Document 1 proposes a method of using conductive fibers excellent in charge removal performance in the wiper. However, since the fineness of the conductive fibers is large, the quality of precision materials such as scratches and damages during wiping is also proposed. It was not possible to use because it affected.

  As conductive fibers, for example, by applying metal plating to the surface of non-conductive fibers and imparting conductivity, or by dispersing conductive carbon black in resin or rubber, and coating this on the fiber surface For example, a conductive coating layer is formed. However, these can be obtained by methods that are complicated and technically difficult to manufacture, or are used for chemical treatment and practical use in the preparation stage for putting conductive fibers into practical use, for example, in the refining process for weaving and knitting. There is a problem that the electrical conductivity is easily lowered by an external action such as wear and repeated washing in the steel, and the practical use is lost.

  Other conductive fibers include metal fibers such as steel fibers, but they are expensive, cause troubles in weaving and dyeing processes, or cause troubles when wiping off. That is the problem.

  Furthermore, a method of obtaining a conductive fiber by fiberizing a polymer in which conductive carbon black is uniformly dispersed has been proposed. However, since the conductive carbon black is contained in a large amount, it is difficult to produce the fiber and the yield is also high. Unfortunately, the cost is high, the fiber properties are remarkably lowered, and it is difficult to produce conductive fibers having fineness.

  Further, as another conductive fiber, for example, a method is proposed in which a conductive carbon black is contained in a core component polymer of a core-sheath type composite fiber and is covered with a sheath made of a normal fiber-forming polymer ( For example, see Patent Document 2). In addition, a conductive fiber has also been proposed in which a substantial portion of the core component containing conductive carbon black penetrates the sheath component and is exposed on the surface of the fiber (see, for example, Patent Document 3).

  In the case of Patent Document 1, it is necessary to keep the core component at 50% or less in order to maintain the fiber physical properties. Therefore, if the non-conductive sheath component coats the core component thickly and the carbon black content in the core component is not increased. There is a problem that fineness cannot be achieved because sufficient performance is not exhibited. Patent Document 2 is intended to solve the problem of Patent Document 1 described above, but because the ratio of the core component containing carbon black exposed to the surface is large, the fineness cannot be achieved.

  Although it is possible to produce conductive fibers with a fineness by using composite fibers that combine a conductive polymer layer and a non-conductive polymer layer, the conductive polymer layer becomes a single fineness after splitting, resulting in low strength and practical use. No practical fineness such as peeling of conductive carbon was obtained.

  As described above, a wiper capable of obtaining a static elimination performance and a wiping performance excellent in long-term durability and a yarn having a particularly fineness that can be used for the wiper have not been proposed.

Japanese Patent Laid-Open No. 11-50350 U.S. Pat. No. 3,803,453 Japanese Examined Patent Publication No. 53-044579

  An object of the present invention is to provide a yarn having excellent static elimination performance and capable of improving the cleanliness after wiping using a textile product containing the yarn more than ever. The object is to provide a yarn having excellent wiping performance as well as performance.

  As a result of intensive studies to solve the above problems, the present inventors have used two different types of crystalline thermoplastic resins, and multilayer bonding containing a conductive resin composition on one side of the crystalline thermoplastic resins. The present inventors have found that the above-mentioned purpose is achieved by a yarn composed of a mold composite fiber, thereby completing the present invention.

That is, the first configuration of the present invention is a yarn produced by dividing a multilayer laminated composite fiber containing two different types of crystalline thermoplastic resins (A) and crystalline thermoplastic resins (B). The crystalline thermoplastic resin (B) contains a conductive resin composition (C),
The content ratio of the conductive resin composition (C) to the crystalline thermoplastic resin (B) is 1 to 50% by mass,
The content ratio of the conductive compound with respect to the conductive resin composition (C) is 15 to 50% by mass,
The SP value (ΦA) of the crystalline thermoplastic resin (A) and the SP value (ΦB) of the crystalline thermoplastic resin (B) are 5.0 ≧ | (ΦB) − (ΦA) | ≧ 1.2 Yes,
The length (a) of the major axis and the length (b) of the minor axis of the fiber cross section of the yarn are (a) / (b) ≧ 1.2,
The single fiber fineness of the yarn is 0.05 to 1.0 dtex,
The yarn has an electrical resistivity of 5.0 × 10 6 to 5.0 × 10 8 Ω / (cm · yarn).

The crystalline thermoplastic resin (A) may be a yarn containing polyamide or polyester, and the crystalline thermoplastic resin (B) may contain polyamide.

  The polyamide of the crystalline thermoplastic resin (B) is a dicarboxylic acid component in which 60 mol% or more of the dicarboxylic acid component is an aromatic dicarboxylic acid component, and 60% mol or more of the diamine component has 6 to 12 carbon atoms. It may be a thermoplastic polyamide comprising a diamine component which is an aliphatic alkylene diamine.

The conductive resin composition (C) may also comprise at least conductive compound (D) and the thermoplastic resin (E).

  The second configuration of the present invention may be a fiber assembly containing at least a part of these yarns, or may be a fiber product containing at least a part of the yarns. It may be a textile product containing the body at least partially.

  A third configuration of the present invention is a method for producing a yarn in which the multilayer laminated composite fiber is peeled and divided by a chemical method using an alkaline hot water solution or an acid hot water solution and / or a physical method.

  The yarn of the present invention has excellent wiping performance as well as a long-term stable static elimination effect.

The schematic diagram of one Embodiment regarding the cross section of the multilayer bonding type | mold composite fiber in this invention. The schematic diagram of one Embodiment regarding the cross section of the multilayer bonded composite fiber different from FIG. 1 in this invention. The schematic diagram of one form regarding the cross section of the composite fiber different from this invention.

  It is important that the conductive yarn of the present invention is produced by dividing a multilayer laminated composite fiber containing two different types of crystalline thermoplastic resins (A) and (B). It is a yarn containing ultrafine fibers made of a thermoplastic resin (A) and ultrafine fibers made of a crystalline thermoplastic resin (B) containing a conductive resin composition (C).

  First, the conductive resin composition (C) in the present invention will be described in detail. In the present invention, the conductive resin composition (C) contains at least a resin and a conductive compound. Examples of the conductive compound include carbon-based conductive compounds such as carbon black, acetylene black, oil furnace black, thermal black, channel black, and ketjen black. In the present invention, it is preferable to use carbon black. More preferably, conductive carbon black described later is used.

The carbon black used in the present invention is preferably a conductive carbon black having a specific electric resistance of 10 ⁻³ to 10 ³ Ω · cm. When carbon black is completely dispersed in particles, the conductivity is generally poor, and when a chain structure called a structure is formed, the conductivity performance is improved and it is called conductive carbon black. Become a thing. Accordingly, when conducting the resin composition with conductive carbon black, it is important to disperse the carbon black without destroying the structure.

  In general, the structure tends to be destroyed when ordinary stretching is performed. Therefore, in the present invention, it is preferable to use a special stretching method disclosed in Japanese Patent No. 49026652 (paragraph 0056 and paragraph 0057). The drawing method has a feature that the structure is hardly broken even though the fiber is drawn. That is, since the conventional general stretching method is a method of forcibly stretching due to the speed difference between the rollers, the fiber is forcibly stretched and the structure is cut. In the case of a method in which free stretching of the fiber is not used instead of the method of stretching in step 1, the structure is difficult to cut because excessive tension is not applied to the fiber.

  And as an electric conduction mechanism of the composition containing conductive carbon black, the one due to the contact of the carbon black chain and the one due to the tunnel effect are considered, but the former is mainly considered. Therefore, the longer the carbon black chain is, the higher the density of the carbon black in the resin composition is, and the higher the contact probability between the carbon blacks, the higher the conductivity. In order to lengthen the chain, if the conductive resin composition (C) is crystallized and has a loose structure in which the amorphous part can undergo molecular motion, the carbon black concentrates on the amorphous part and the amorphous part. As a result, the carbon concentration becomes higher and the conductive performance becomes higher.

  In the present invention, the conductive compound contained in the conductive resin composition (C) is preferably contained in an amount of 15 to 50% by mass, more preferably 20 to 40% by mass with respect to the conductive resin composition (C). . When the content of the conductive compound is less than 15% by mass, the intended conductivity cannot be obtained and sufficient static elimination performance may not be exhibited. On the other hand, when it exceeds 50% by mass, further improvement in conductivity is not recognized, and the fluidity of the resin composition (C) is remarkably lowered and the spinnability is extremely deteriorated.

  Next, the resin constituting the conductive resin composition (C) of the present invention will be described. The resin constituting the resin composition (C) preferably has a melting point of 200 ° C. or higher from the viewpoint of practical durability, and such a resin is preferably a thermoplastic polyamide or a thermoplastic polyester. In particular, it is more preferable to use thermoplastic polyamide from the viewpoint that a large amount of a conductive compound can be added and the conductive performance can be further improved. Specifically, nylon 12, nylon 11, nylon 6, nylon 66, nylon elastomer, semi-fragrance Group polyamide and the like.

  Examples of the thermoplastic polyester include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, 4,4′-dicarboxydiphenyl, and 5-sodium sulfoisophthalic acid, azelaic acid, Dicarboxylic acid component such as aliphatic dicarboxylic acid such as sebacic acid and aliphatic diol such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, polyethylene glycol, polytetramethylene glycol; ethylene of bisphenol A or bisphenol S Examples thereof include an aromatic diol such as an oxide adduct; and a fiber-forming polyester formed using a diol component such as an alicyclic diol such as cyclohexanedimethanol. Among these, polyesters containing 80 mol% or more, particularly 90 mol% or more of ethylene terephthalate units or butylene terephthalate units, which are general-purpose polyesters, are preferable.

  In particular, a polybutylene terephthalate resin, that is, a polyester resin containing 80 mol% or more of a butylene terephthalate unit is preferable because a conductive compound can be easily kneaded and crystallized easily, so that high conductive performance can be obtained. Polyethylene terephthalate resin can be used, but if a large amount of the conductive compound is added, the spinnability at the time of melt spinning is lowered. At that time, it is conceivable to use copolymerized polyethylene terephthalate in order to improve spinnability. However, when copolymerized polyethylene terephthalate is used, the crystallinity is generally lowered and the conductive performance is lowered. From the above, the polybutylene terephthalate resin, which is a polyester resin that easily forms crystals, is particularly excellent. Moreover, it is necessary from the point of practical durability that melting | fusing point of resin which comprises a conductive layer is 200 degreeC or more. Preferably it is 210 degreeC or more and 250 degrees C or less.

  The resin constituting the conductive resin composition (C) is preferably the same as the crystalline thermoplastic resin (B) described below because the adhesion to the crystalline thermoplastic resin (B) is improved. .

  Next, the crystalline thermoplastic resin (B) will be described. The crystalline thermoplastic resin (B) plays an important role in maintaining long-term durability performance without maintaining good processability and causing interfacial peeling from the conductive resin composition (C). Yes. Preferred examples of the resin contained in the crystalline thermoplastic resin (B) include polyolefins such as thermoplastic polyamide, thermoplastic polyester, polypropylene, polybutene, and polymethylpentene, and copolymers thereof, and 25 to 70 mol% of ethylene units. Modified polyvinyl alcohol containing mol% can be used. In particular, a thermoplastic crystalline resin having a melting point of 210 ° C. or higher is preferably used in terms of durability. A resin having poor spinnability is basically unsuitable as a resin contained in the crystalline thermoplastic resin (B) of the present invention.

  As described above, in the present invention, it is preferable to use thermoplastic polyamide as the crystalline thermoplastic resin (B). 4,6-nylon, 6-nylon, 6,6-nylon, 6,10-nylon, 6 , 12-nylon, 11-nylon, 12-nylon, and other aliphatic polyamides and aromatic polyamides. More preferable examples include 6-nylon, 6,6-nylon, 6,12-nylon, and 12-nylon. Particularly, dicarboxylic acid in which 60 mol% or more of the dicarboxylic acid component is an aromatic dicarboxylic acid component. A thermoplastic polyamide comprising a component and a diamine component in which 60 mol% or more of the diamine component is an aliphatic alkylene diamine having 6 to 12 carbon atoms is preferable because it has low hygroscopicity and leads to stability of conductive performance.

  Examples of the thermoplastic polyester include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, 4,4′-dicarboxydiphenyl, 5-sodium sulfoisophthalic acid; azelaic acid, Dicarboxylic acid component such as aliphatic dicarboxylic acid such as sebacic acid and aliphatic diol such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, polyethylene glycol, polytetramethylene glycol; ethylene of bisphenol A or bisphenol S Examples thereof include an aromatic diol such as an oxide adduct; and a fiber-forming polyester formed using a diol component such as an alicyclic diol such as cyclohexanedimethanol. Among them, polyesters containing ethylene terephthalate units and / or butylene terephthalate units, which are general-purpose polyesters, are 80 mol% or more, particularly 90 mol% or more, and modified polyesters containing a small amount of a third component can also be used. It is. Further, these may contain a small amount of additives, fluorescent whitening agents, stabilizers and the like. These polyesters have good melt viscosity characteristics when fiberized, and are excellent in fiber properties and heat resistance. Of these, polyethylene terephthalate-based polyester is preferred in terms of fiberizing process properties, fiber properties, and durability. In particular, a polyester having a melting point of 240 ° C. or higher and 280 ° C. or lower is preferable. Furthermore, it is preferable that a resin having a melting point higher by 10 to 50 ° C. than the resin constituting the conductive resin composition (C) is included in the crystalline thermoplastic resin (B).

  Furthermore, in the present invention, the SP value (ΦB) of the crystalline thermoplastic resin (B) containing the conductive resin composition (C) and the SP value (ΦC) of the conductive resin composition (C) are 0 ≦ It is preferable that | (ΦB) − (ΦC) | ≦ 1.1 is satisfied. A combination satisfying this condition has good adhesion between both polymers, hardly causes interfacial peeling, and is excellent in terms of fiber properties. When | (ΦB) − (ΦC) | exceeds 1.1, interfacial peeling is likely to occur, and durability in practical use is difficult to obtain.

  As an aspect in which the above-mentioned crystalline thermoplastic resin (B) contains the conductive resin composition (C), the conductive resin composition (C) is surrounded in the fiber cross section from the viewpoint of the conductive performance and the wiping performance. The crystalline thermoplastic resin (B) is preferably coated. In particular, it is preferable that the conductive resin composition (C) has a core-sheath structure in which the core component and the crystalline thermoplastic resin (B) are sheath components. Moreover, it is preferable that content of the conductive resin composition (C) in a crystalline thermoplastic resin (B) is 1-50 mass% with respect to a crystalline thermoplastic resin (B). More preferably, it is 3-45 mass%, More preferably, it is 5-40 mass%.

  On the other hand, in the multilayer bonded composite fiber of the present invention, the crystalline thermoplastic resin (A) containing no conductive compound can maintain good processability and easily divide the multilayer bonded composite fiber. Therefore, it is necessary to form a multilayer laminated composite fiber with a resin different from the crystalline thermoplastic resin (B). Preferred examples of the crystalline thermoplastic resin (A) include polyolefins such as thermoplastic polyamides, thermoplastic polyesters, polypropylene, polybutene, polymethylpentene, and the like mentioned as the crystalline thermoplastic resin (B). Examples thereof include polymers and modified polyvinyl alcohol containing 25 to 70 mol% of ethylene units.

  Furthermore, the SP value (ΦA) of the crystalline thermoplastic resin contained in the multilayer laminated composite fiber of the present invention and the SP value (ΦB) of the crystalline thermoplastic resin (B) are 5.0 ≧ | (ΦB ) − (ΦA) | ≧ 1.2. When | (ΦB) − (ΦA) | is smaller than 1.2, the splitting property of the multi-layer bonded composite fiber cannot be obtained, and the aimed ultrafine fiber cannot be obtained. On the other hand, when | (ΦB) − (ΦA) | is larger than 5.0, stable fiberizing process passability cannot be obtained. Preferably 4.0 ≧ | (ΦB) − (ΦA) | ≧ 1.5, more preferably 3.5 ≧ | (ΦB) − (ΦA) | ≧ 2.0.

Here, the solubility parameter SP value [(cal / cm ³ ) ^1/2 ] of the present invention is the polymer handbook second edition (Polymer Handbook SECOND EDITION) (John Wiley & Sons, Inc. 1975) IV-339 Table B1 or This is a value calculated using the following formula: Group Molecular Attraction Constants (G) and molecular weight (M), density (d), resin structural formula, SP value = d × ΣG / M.

  In the present invention, 0.05 to 10 inorganic fine particles other than the conductive compound having an average particle diameter of 0.01 to 1 μm are contained in the crystalline thermoplastic resin (A) and / or the crystalline thermoplastic resin (B). It may be contained in a proportion of mass%, and is preferable from the viewpoint of spinnability of the multilayer laminated composite fiber and further from the viewpoint of knitting and weaving. If the content of the inorganic fine particles is less than 0.05% by mass, loops, fluff, fineness spots, etc. are likely to occur in the obtained conductive yarn, and if it exceeds 10% by mass, the processability is poor and the yarn is broken. Cause. More preferably, the inorganic fine particles may be contained at a ratio of 0.2% by mass to 5% by mass.

  Any inorganic fine particles can be used as long as they have substantially no deterioration effect on the resin and are excellent in stability by themselves. Typical examples of such inorganic fine particles include inorganic fine particles such as silica, alumina, titanium oxide, calcium carbonate, and barium sulfate. These may be used alone or in combination of two or more.

  The average particle size of the inorganic fine particles is preferably 0.01 to 1 μm, more preferably 0.02 to 0.6 μm. When the average particle size is less than 0.01 μm, loops, fluff, fineness spots and the like are generated in the obtained fiber even if slight fluctuations occur in the tension applied to the yarn during drawing. On the other hand, if the average particle size exceeds 1 μm, the spinning property and stretchability of the fiber are lowered, and it is easy to generate spun yarn and stretched wrinkles. Here, the average particle diameter of the inorganic fine particles herein refers to a value obtained using a centrifugal sedimentation method. Moreover, the average particle diameter of this invention represents a primary average particle diameter.

  The method for adding the inorganic fine particles is not particularly limited, and may be added and mixed so that the inorganic fine particles are uniformly mixed in the resin at any stage from the polymerization of the polymer to immediately before melt spinning.

  In the present invention, in the crystalline thermoplastic resin (A) and / or the crystalline thermoplastic resin (B), if necessary, a fluorescent brightener, a stabilizer, an antioxidant, an ultraviolet absorber, a water You may contain 1 type (s) or 2 or more types of a decomposition inhibitor, an antistatic agent, a flame retardant, a coloring agent, and another additive.

  Using the above-described crystalline thermoplastic resin (A), crystalline thermoplastic resin (B), and conductive resin composition (C), a multilayer bonded composite fiber as shown in FIGS. 1 and 2 is produced. Thus, the conductive yarn of the present invention can be obtained. In the multilayer laminated composite fiber, the composite ratio of each component (A), (B), (C) is (A) :( B) :( C) = 20: 79.1: 0.9- It is preferable that (A) :( B) :( C) = 50: 25: 25 (mass ratio). When the crystalline thermoplastic resin (A) is less than 20% by mass or greater than 50% by mass, it becomes difficult to spin as a stable composite structure. In particular, it becomes difficult for the conductive resin composition (C) and the crystalline thermoplastic resin (B) containing the conductive resin composition to stably obtain fibers having continuity in the fiber cross section. In a preferred embodiment, if the ratio of the crystalline thermoplastic resin (B) covering the periphery of the conductive resin composition (C) is less than 25% by mass, durability against external action during wiper may be insufficient. If it is greater than 79.1% by mass, stable continuity of the fiber cross section may not be obtained. Furthermore, when the conductive resin composition (C) is less than 0.9% by mass, stable conductive performance cannot be obtained, and when it is more than 25% by mass, stable cross-section formation of the composite fiber is often not obtained. The composite ratio of each component is more preferably in the range of (A) :( B) :( C) = 30: 62: 8 to (A) :( B) :( C) = 45: 37: 18. Here, the ratio of (A), (B), (C) satisfies (A) + (B) + (C) = 100.

  A multilayer containing two different types of crystalline thermoplastic resins (A) and crystalline thermoplastic resins (B) as described above, and containing the conductive resin composition (C) in the crystalline thermoplastic resin (B). The yarn of the present invention can be obtained by peeling and dividing the bonded composite fiber by a chemical method using an alkali hot water solution or an acid hot water solution and / or a physical method. Specifically, it is easy to divide by applying a chemical method such as treatment with an aqueous alkali solution, treatment with a polyamide swelling agent and / or a physical method such as false twisting. In the case of a chemical method, it is preferable to select a treatment method for partially dissolving the crystalline thermoplastic resin (A). Thus, the yarn of the present invention produced by peeling and dividing the multi-layer bonded composite fiber becomes an ultrafine fiber. The ultrafine fiber made of the crystalline thermoplastic resin (A) and the ultrafine fiber made of the crystalline thermoplastic resin (B) containing the conductive resin composition (C) have an edge effect because the fiber cross section has a corner. Therefore, for example, superior wiping performance is exhibited as compared with the round cross section shown in FIG.

  In the yarn of the present invention, a crystalline thermoplastic resin (B) containing a yarn comprising the crystalline thermoplastic resin (A) after dividing the multilayer laminated composite fiber and the conductive resin composition (C) It is important that the fiber cross section of the yarn satisfies (a) / (b) ≧ 1.2. Here, (a) represents the length of the major axis of the fiber cross section, and (b) represents the length of the minor axis of the fiber cross section. By making the fiber cross section to be a flat cross section satisfying (a) / (b) ≧ 1.2, excellent wiping performance is exhibited due to an increase in contact area and edge effect in wiping properties. Preferably (a) / (b) ≧ 1.5, more preferably (a) / (b) ≧ 2.0. In the present invention, the length (a) of the major axis and the length (b) of the minor axis of the fiber cross section are cut along the fiber cross section using an enlarged photograph of the fiber cross section, and the length of the cross section is obtained. The lengths of the short axis and the short axis can be measured, and the ratio can be easily obtained.

  Further, in the yarn of the present invention, a crystalline thermoplastic containing the yarn comprising the crystalline thermoplastic resin (A) after the multi-layer bonded composite fiber is peeled and divided, and the conductive resin composition (C). It is important from the viewpoint of wiping performance that the single fiber fineness of the yarn made of the resin (B) is 0.05 to 1.0 dtex. Preferably it is 0.1-0.8 dtex, More preferably, it is 0.2-0.5 dtex.

The electrical resistivity of the yarn of the present invention is preferably 5.0 × 10 ^{6 to} 5.0 × 10 ⁸ Ω / (cm · yarn). When the electrical resistivity satisfies this range, a stable static elimination effect is exhibited, and as a result, it has excellent wiping performance over a long period of time. A more preferable electrical resistivity is 6.0 × 10 ^{6 to} 3.0 × 10 ⁸ Ω / (cm · yarn). In order to make the electrical resistivity less than 5.0 × 10 ⁶ , it is necessary to increase the content of the conductive resin composition (C), but there are problems of deterioration of the fiberizing process and falling off during wiping. Therefore, it is not preferable. When the electrical resistivity exceeds 5.0 × 10 ⁸ , sufficient wiping performance cannot be obtained. In the present invention, the multi-layer bonded composite fiber is divided, but it is important that the ultrafine fiber made of the crystalline thermoplastic resin (A) exists after the division, and the crystal containing the conductive resin composition (C) Long-lasting durability can be imparted to the ultrafine fibers made of the heat-resistant thermoplastic resin (B), and the wiping performance can be stably maintained.

  The production method of the multi-layer bonded composite fiber in the present invention is not particularly limited. For example, using a melt spinning apparatus used for manufacturing a known multi-layer bonded composite fiber, composite spinning is performed, and then stretching is performed. It may be manufactured by a method, or may be manufactured by a method in which high-speed spinning is performed and the drawing step is omitted. However, in order to cover the conductive resin composition (C) as much as possible with the crystalline thermoplastic resin (B), the introduction hole of the conductive resin composition (C) in the distribution plate in the spinning device It is preferable to adjust the positional relationship of the introduction holes for the crystalline thermoplastic resin (B) or adjust the composite ratio of the conductive resin composition (C) and the crystalline thermoplastic resin (B).

  It is preferable that the degree of division after the division treatment of the multilayer laminated composite fiber in the present invention is 30% or more. Here, the degree of division refers to a value measured by the following method. That is, any 100 cross-sections of the composite fiber in the area to be measured (including those that are split into fiber bundles and those that are not partly split) are observed using a scanning electron microscope. Then, the number (N) of the divided ultrafine fibers actually divided and present is counted. In this case, a composite fiber that is not divided at all is counted as one, and a partially divided composite fiber is counted as a total of a half-divided composite fiber and an ultrafine fiber that is divided therefrom. Next, the number (Np) of ultrafine fibers after division obtained when the 100 composite fibers are assumed to be completely divided is calculated, and the value of N / Np × 100 is divided in the yarn of the present invention. Degree. In addition, the said division | segmentation degree immerses the composite fiber of this invention for 5 to 20 minutes at 98 degreeC in alkaline aqueous solution (NaOH density | concentration 4g / L) or an acid solution (benzoic acid 1g / L) as division | segmentation process conditions. Determined for those that have been stirred and dried.

  In the present invention, it is necessary to adjust the single fiber fineness and the total dtex number of the multilayer bonded composite fiber so that the final single fiber fineness is 0.05 to 1.0 dtex. Although it can be suitably adjusted according to the application etc., the method of the present invention is a composite having a single fiber fineness of 0.5 to 6 dtex and a total dtex number of 30 to 200 dtex, particularly as a multi-layer bonded composite fiber before division. Suitable for producing fibers (multifilament yarn). Here, the total dtex represents the fineness as a multifilament.

  The yarn produced from the multilayer laminated composite fiber of the present invention can be used as various fiber assemblies. The fiber assembly in the present invention is not limited to the woven fabric and non-woven fabric made of the yarn of the present invention, but also the woven fabric and non-woven fabric using a part of the yarn, for example, normal natural fiber, chemical fiber, It may be an interwoven fabric with synthetic fibers, a knitted fabric as a blended yarn, a non-woven fabric, or the like. The yarn of the present invention occupying the woven or non-woven fabric is preferably 1% by mass or more, particularly 3% by mass or more from the viewpoint of obtaining the sufficient effect of the present invention. In addition, even if the knitting, weaving or non-woven fabric is followed by raising with a needle cloth raising as necessary, there is no problem with the present invention.

  The yarn of the present invention can be used as various textile products. Furthermore, you may use the said fiber assembly for a textile product. Specifically, it can be suitably used for textile products such as wipers.

  Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In the following examples, the spinnability of the multilayer laminated composite fiber, the measurement of the electrical resistivity of the yarn, the wiping property of the obtained knitted fabric (wiping cloth), and the charge amount were measured or evaluated as follows. .

[Spinnability of multilayer laminated composite fiber]
20 kg of multi-layer bonded composite fiber was spun and examined for the presence or absence of yarn breakage during spinning, and the presence or absence of fluff in the obtained composite fiber was visually observed and evaluated according to the following evaluation criteria.
<Evaluation criteria for spinnability of composite fibers>
A: No yarn breakage occurred during spinning, and no fluff was generated in the obtained multilayer laminated composite fiber, and the spinnability was very good.
○: No yarn breakage occurred during spinning, and the resulting multi-layer bonded composite fiber had slight fluff, but the spinnability was almost good.
Δ: When 100 kg is spun, yarn breakage occurs up to three times and the spinnability is poor.
X: When 100 kg is spun, yarn breakage occurs more than three times, and the spinnability is extremely poor.

[Electric resistivity R of fiber]
A DC voltage of 25 to 500 V was applied to the yarn sample set on the parallel clip electrode by the voltage ammeter method, and the voltage and current value flowing through the sample at that time were determined according to Ohm's law. Further, the electrical resistivity R (Ω / (cm · yarn)) defined in the present invention is obtained when 100V is applied.

[Wipeability of wiping cloth]
Using a wiping cloth containing the yarn of the present invention as a test cloth, a slide glass on which a contaminant for wiping performance evaluation is adhered is temporarily bonded to a flat test table of a friction tester (testing machine conforming to JIS L0823). Then, wiping was carried out with a friction element equipped with a test cloth. The wiping load was 200 g, the wiping width was 20 mm, and the wiping stress was 100 g / mm. Wiping was performed several times, the transmitted light rate before and after wiping was measured, and calculated as follows.
Wiping rate (%) = [(Wn−W ₀ ) / (Wb−W ₀ )] × 100
Wb: Transmittance of slide glass at 380 nm or 580 nm Wn: Transmittance after wiping W ₀ : Transmittance before wiping <Preparation of sample to which contaminant is attached>
a. Nicotine A slide glass (20 sheets) was placed horizontally in a fumigation box, fumigated with about 20 cigarettes (pieces), and pollutants were adhered mainly with nicotine. The visible light transmittance was adjusted to 20% or less.
b. Lubricating oil A frame was placed on a slide glass, and a commercially available lubricating oil was sprayed from a distance of 30 cm for 3 seconds to prepare a sample.
c. Paste Paste (0.5 g / cm ² ) composed of corn starch 10 g / L was applied to a slide glass.

[Charging charge density of wiping cloth]
The wiping cloth containing the yarn of the present invention was used as a test cloth according to RIISTR78-1 of the static electricity safety guide issued by the Ministry of Labor Safety Institute (measured after being left in a room at 22 ° C. and 30% RH for 24 hours). For washing, 1:30 bath ratio, standard detergent (weakly alkaline) added, wash for 5 minutes at 40 ° C, then rinse twice with 1:30 bath water, rinse for 5 minutes repeated 250 times a process of performing, comparing the charge density after washing the initial charge density ^{(μC / m 2) (μC} / m 2).

[Measurement method of single fiber fineness]
The measurement was performed under the conditions of a temperature of 25 ° C. and a humidity of 65% using a motorcycle blow type fineness measuring device (Denial Computer DC-11, manufactured by Search Control Electric Co., Ltd.). The measurement was performed 5 times and the average value was used.

[Example 1]
Nylon 6 containing 35% by mass of conductive carbon black (oil absorption: 115 cc / 100 g) as the conductive resin composition (C), titanium oxide having a primary average particle size of 0.4 μm as the crystalline thermoplastic resin (B) Of polyethylene terephthalate containing 0.5% by mass of titanium oxide having a primary average particle size of 0.5 μm as a crystalline thermoplastic resin (N) 6 containing 0.5% by mass of nylon 6 (“1013BK” manufactured by Ube Industries, Ltd.) (A) :( B) :( C) = 30: 56: 14 (mass ratio), using a melt viscosity of 0.65), each measured with a gear pump, then fed into a spinning pack, It discharged at a temperature of 290 ° C. and wound up at a speed of 1000 m / min. Subsequently, the film was stretched with a roller heater at 75 ° C. at a magnification of 2.5, and heat-set with a plate heater at 130 ° C. to obtain a stretched yarn of 56 dtex / 12 filament. The cross section of the yarn was a vertically split type cross section (11 layers alternately laminated type) structure as shown in FIG. This multilayer bonded composite fiber was false twisted at a false twist number of 4100 T / M and a temperature of 170 ° C. and divided to obtain conductive yarns made of ultrafine fibers having a single fiber fineness of 0.47 dtex.

  Next, nylon 6 ("1013BK" manufactured by Ube Industries, Ltd.) and polyethylene terephthalate having an intrinsic viscosity of 0.70 were melt-extruded with separate extruders, and the composite ratio was nylon 6: polyethylene terephthalate = 33: Each was measured with a gear pump so as to be 67 (mass ratio), then supplied into a spinning pack, discharged at a base temperature of 290 ° C., and wound at a speed of 1000 m / min. Subsequently, the film was drawn with a roller heater at 75 ° C. at a magnification of 2.9 times, and heat-set with a plate heater at 130 ° C. to obtain a drawn yarn of 84 dtex / 24 filament. The cross section of the yarn was a vertically divided type cross section (11 layers alternately laminated type) structure. Subsequently, the drawn yarn was false twisted at a false twist number of 3390 T / M and a temperature of 170 ° C., and divided. The single fiber fineness of the crimped yarn made of polyester and polyamide obtained was about 0.32 dtex. This ultrafine fiber is combined into two yarns (167 dtex / 48 filament), and further comprises a conductive material comprising the above-described crystalline thermoplastic resin (A), crystalline thermoplastic resin (B), and conductive resin composition (C). The yarn was mixed to create a tubular knitted fabric, and relaxed, washed with water, dried, preset, reduced with a slight alkali (5 wt% reduced), washed with water and dried to obtain a fabric. Using this fabric, performance evaluation as a wiping cloth was performed. The results are shown in Tables 1 and 2.

[Examples 2 to 7]
The conductive resin composition (C), the crystalline thermoplastic resin (B) containing the conductive resin composition (C), the type, the composite ratio, and the spinning nozzle part forming the cross section of the crystalline thermoplastic resin (A) were changed, and Table 1 In the same manner as in Example 1 except that the values shown in Table 2 were used, a multi-layer bonded composite fiber, a conductive yarn obtained therefrom, and a wiping cloth were prepared using the same, and were used for performance evaluation. The results are shown in Table 2.

[Comparative Example 1 and Comparative Example 2]
The values shown in Tables 1 and 2 were changed by changing the spinning nozzle part that forms the core-sheath cross-section with the conductive resin composition (C) as the core and the crystalline thermoplastic resin (B) containing it as the sheath component. A core-sheath type composite fiber having a round cross section shown in FIG. 3 was prepared in the same manner as in Example 1 except that the cross section was changed to a cross section. The results are shown in Tables 1 and 2.

[Comparative Example 3, Comparative Example 4]
The conductive resin composition (C), the crystalline thermoplastic resin (B) containing the conductive resin composition (C), the type, the composite ratio, and the spinning nozzle part forming the cross section of the crystalline thermoplastic resin (A) were changed, and Table 1 The yarn obtained by dividing the multi-layer bonded composite fiber and the multi-layer bonded composite fiber was obtained in the same manner as in Example 1 except that the values shown in Table 1 were obtained, and a wiping cloth was further prepared for performance evaluation. . The results are shown in Table 2.

  About Examples 1-7, all show the wiping performance which was excellent in the initial stage and after washing, and are excellent in long-term durability performance. In Comparative Examples 1 to 3, the wiping performance was insufficient, but the thinning was insufficient and the performance was poor due to the insufficient surface area and charge removal. In Comparative Example 4, the fiberization processability was not obtained and the wiping performance was poor.

  According to the present invention, it is possible to provide a yarn excellent in static elimination performance, in particular, a yarn capable of improving the cleanliness after wiping more than ever, and further excellent in wiping performance at the same time as a stable static elimination effect. Yarn can be provided.

1 Conductive resin composition (C)
2 Crystalline thermoplastic resin (B)
3 Crystalline thermoplastic resin (A)

Claims (9)

A yarn produced by dividing a multilayer laminated composite fiber containing two different types of crystalline thermoplastic resins (A) and crystalline thermoplastic resins (B), the crystalline thermoplastic resin (B) contains the conductive resin composition (C),
The content ratio of the conductive resin composition (C) to the crystalline thermoplastic resin (B) is 1 to 50% by mass,
The content ratio of the conductive compound with respect to the conductive resin composition (C) is 15 to 50% by mass,
The SP value (ΦA) of the crystalline thermoplastic resin (A) and the SP value (ΦB) of the crystalline thermoplastic resin (B) are 5.0 ≧ | (ΦB) − (ΦA) | ≧ 1.2 Yes,
The length (a) of the major axis and the length (b) of the minor axis of the fiber cross section of the yarn are (a) / (b) ≧ 1.2,
The single fiber fineness of the yarn is 0.05 to 1.0 dtex,
A yarn having an electrical resistivity of 5.0 × 10 ⁶ to 5.0 × 10 ⁸ Ω / (cm · yarn).   The yarn according to claim 1, wherein the crystalline thermoplastic resin (A) contains polyamide or polyester.   The yarn according to claim 1 or 2, wherein the crystalline thermoplastic resin (B) contains polyamide.   The polyamide is a dicarboxylic acid component in which 60 mol% or more of the dicarboxylic acid component is an aromatic dicarboxylic acid component, and a diamine component in which 60 mol% or more of the diamine component is an aliphatic alkylenediamine having 6 to 12 carbon atoms. The yarn according to claim 3, which is a thermoplastic polyamide.   The yarn according to any one of claims 1 to 4, wherein the conductive resin composition (C) contains at least a conductive compound (D) and a thermoplastic resin (E). A fiber assembly containing at least a part of the yarn according to any one of claims 1 to 5 . A textile product containing at least a part of the yarn according to any one of claims 1 to 5 . The fiber product of Claim 7 which contains the fiber assembly of Claim 6 in at least one part. The method for producing a yarn according to any one of claims 1 to 5 , wherein the multilayer laminated composite fiber is separated by a chemical method and / or a physical method using an alkaline hot water solution or an acid hot water solution.