WO2012090626A1

WO2012090626A1 - Thread material for void-containing thread production, and void-containing thread

Info

Publication number: WO2012090626A1
Application number: PCT/JP2011/077063
Authority: WO
Inventors: 清一渡辺; 小倉　徹; 後藤　靖友; 伸輔高橋
Original assignee: 富士フイルム株式会社
Priority date: 2010-12-28
Filing date: 2011-11-24
Publication date: 2012-07-05
Also published as: JP2012140721A

Abstract

Provided is thread material for void-containing thread production including a minute crystal nucleus and satisfying conditions such that it is possible by stretching to stably and efficiently produce void-containing thread having a metallic luster, a high degree of reflection, and excellent aesthetics and design. Thread material for void-containing thread production for producing void-containing thread having an independent void therein, wherein: when stretched, the void is formed so as to be positioned in the interior thereof in the direction of stretching; given that the average length of the void is L (μm), and the average diameter of the void in the direction orthogonal to the direction in which the void is positioned is r (μm), then the ratio of L/r is 10 or greater; a crystal nucleus having a crystallite size of 2-5nm in a crystal surface of a (010) surface is included therein the thread material; and the degree of crystallization is 5-15%, inclusive.

Description

Void-containing yarn manufacturing yarn and void-containing yarn

The present invention relates to a void-containing yarn production yarn and a void-containing yarn produced from the void-containing yarn production yarn.

In recent years, various efforts have been made to improve the functionality, aesthetics, and design of fibers. For example, by changing the fiber cross-sectional shape, or improve the water absorption, by reforming a polymer, and increasing the light weight, or improve fibril resistance, and or improve the bathochromic (e.g. , See Patent Document 1).
However, in the method for producing a fiber having a hollow structure described in Patent Document 1, in order to achieve a high hollow ratio in order to reduce the weight of the fiber, there is a technique in which a polymer melt-extruded from a discharge hole of a die is bonded. It is necessary and the process is complicated.

A hollow structure fiber can also be produced by adding a sodium sulfonate compound in the polymerization step, and melt-kneading polystyrene or polymethylmethacrylate into the resulting polymer pellets and melt-extruding from a melt spinning hollow die. (See Patent Document 2).
However, in the method described in Patent Document 2, it is difficult to obtain a uniform product because it requires complicated measures to manage the ratio of additive materials and the like, and it is difficult to obtain a uniform product. Therefore, there is a problem that separation is difficult during recycling, and in some cases it must be discarded.

As a fiber having improved aesthetics and design, it is strongly desired to provide a fiber having a metallic luster (shininess). As such a fiber, an excellent fiber such as a reflectance has been proposed by having a void inside (refer to Patent Document 3). Such a fiber can be produced by drawing a filament having a fine crystal nucleus inside.

JP 2002-173824 A JP 2005-256243 A JP 2009-191383 A

However, the quality of such fibers greatly depends on the properties of the yarn for producing the yarn, that is, the crystallite size and crystallinity of the crystal nucleus included in the yarn.
In addition, in the production of fibers shown in Patent Document 3 and the like, the type of resin used as a raw material and the drawing conditions have been studied, but the properties of the yarn have not been sufficiently studied, and the wire breaks during drawing. Thus, there are problems such that stable stretching cannot be performed and sufficient reflectance cannot be obtained even when stretching.
Therefore, the present situation is that an improvement in the quality of the yarn used for the production of yarn is desired in order to stably produce a yarn having a metallic luster, high reflectivity and excellent aesthetics and design.

This invention makes it a subject to solve the said various problems in the past and to achieve the following objectives. That is, the present invention encloses fine crystal nuclei with conditions capable of stably and efficiently producing a void-containing yarn having a metallic luster, high reflectivity and excellent aesthetics and design by stretching. An object of the present invention is to provide a yarn for producing void-containing yarn.

In order to solve the above-mentioned problems, the present inventors have made extensive studies and obtained the following knowledge. That is, the quality, such as reflectivity, in the void-containing yarn (also referred to as void yarn or void-containing yarn) depends on the crystallite size and crystallization of the crystal nucleus inside the void-containing yarn production yarn used for producing the void-containing yarn. Therefore, it has a metal-like luster by drawing a void-containing yarn for producing yarn containing a specific crystallite size and having a specific crystallinity and stretching it. The inventors have found that a void-containing yarn having high reflectivity and excellent aesthetics and design can be produced stably and efficiently, and the present invention has been completed.

The present invention is based on the above findings by the present inventors, and means for solving the above problems are as follows. That is,
<1> A void-containing yarn-manufacturing yarn for producing a void-containing yarn having an independent cavity inside. When drawn, the void is formed in an oriented state in the drawing direction. The L / r ratio is 10 or more when the average length is L (μm) and the average diameter of the cavities in the direction perpendicular to the orientation direction of the cavities is r (μm), and the crystal plane of the (010) plane A void-containing yarn for producing a yarn containing voids having a crystallite size of 2 nm to 5 nm and a crystallinity of 5% to 15%.
<2> The void-containing yarn producing yarn according to <1>, wherein the average diameter is 10 μm to 500 μm.
<3> A void-containing yarn manufacturing yarn according to any one of <1> to <2>, which is made of a crystalline polymer.
<4> The void according to any one of <1> to <3>, wherein the reflectance is 0.1% to 10%, and the reflectance of the void-containing yarn obtained by stretching is 30% to 90%. This is a yarn for producing contained yarn.
<5> Any one of <1> to <4>, in which a crystal nucleus of a (010) plane has a crystallite size of 2.5 nm to 3.5 nm and a crystallinity of 7% to 10% The void-containing yarn-producing yarn described in 1.
<6> A void-containing yarn obtained by drawing the void-containing yarn-producing yarn according to any one of <1> to <5>, wherein a cavity is formed in an oriented state in the drawing direction. The L / r ratio is 10 or more when the average length of the cavity is L (μm) and the average diameter of the cavity in the direction orthogonal to the orientation direction of the cavity is r (μm). It is a void-containing yarn.
<7> The void-containing yarn according to <6>, wherein the reflectance is 30% to 90%.

According to the present invention, the above-mentioned problems can be solved and the above-mentioned object can be achieved, and by stretching, a void-containing yarn having a metallic luster, high reflectivity and excellent aesthetics and design is stabilized. Thus, it is possible to provide a void-containing yarn-producing yarn that includes fine crystal nuclei with conditions that allow efficient production.

FIG. 1A is an example of a cross-sectional view of a void-containing yarn produced using the void-containing yarn-producing yarn of the present invention. FIG. 1B is an example of a cross-sectional view of a void-containing yarn produced using the void-containing yarn-producing yarn of the present invention. FIG. 2A is a diagram for explaining an aspect ratio, and is a perspective view of a void-containing yarn. FIG. 2B is a view for explaining the aspect ratio, and is a cross-sectional view taken along the line A-A ′ of the void-containing yarn in FIG. 2A. FIG. 2C is a diagram for explaining the aspect ratio, and is a cross-sectional view taken along the line B-B ′ of the void-containing yarn in FIG. 2A. FIG. 3A is a perspective view of the void-containing yarn for explaining the aspect ratio. FIG. 3B is a diagram for explaining the aspect ratio, and is a cross-sectional view taken along the line A-A ′ of the void-containing yarn in FIG. 3A. FIG. 3C is a diagram for explaining the aspect ratio, and is a B-B ′ sectional view of the void-containing yarn in FIG. 3A. FIG. 4 is a diagram showing an example of a drawing method when producing a void-containing yarn using the void-containing yarn-producing yarn of the present invention. FIG. 5 is a diagram showing the relationship between the crystallite size of the (010) plane of the crystal nucleus of the void-containing yarn-producing yarn and the yield of the void-containing yarn. Vertical axis: yield of void-containing yarn (%), horizontal axis: crystallite size (nm) on (010) plane. FIG. 6 is a diagram showing the relationship between the crystallinity of the void-containing yarn-manufacturing yarn and the yield of the void-containing yarn. Vertical axis: yield of void-containing yarn (%), horizontal axis: crystallinity (%).

(Various yarn for yarn containing voids)
The void-containing yarn-producing yarn of the present invention includes at least a crystal nucleus. The void-containing yarn manufacturing yarn can be produced by drawing the void-containing yarn.

<Crystallite size of crystal plane of (010) plane>
The crystallite size of the crystal plane of the (010) plane of the crystal nucleus included in the void-containing yarn-producing yarn is 2 nm to 5 nm, preferably 2.1 nm to 4 nm, and preferably 2.5 nm to 3.5 nm. Particularly preferred. When the crystallite size of the (010) plane is less than 2 nm, the crystallite size is too small, and when producing a void-containing yarn, sufficient metal-like gloss and high reflectivity are obtained even when drawn. In some cases, when the thickness exceeds 5 nm, the crystallite size is too large, and the void-containing yarn may be cut by stretching. The “(010) plane” herein refers to a crystal plane represented by a set of three disjoint integers (hkl) generally called a plane index or a Miller index. This is explained in the literature on X-ray diffraction (for example, X-ray diffraction technology Kazutake Takara and Satoshi Kikuta, The University of Tokyo Press, 1981, p23-p39).
The crystallite size of the (010) plane can be measured by, for example, X-ray diffraction.

<Crystallinity>
The degree of crystallinity of the void-containing yarn manufacturing yarn is 5% to 15%, preferably 5% to 12%, more preferably 7% to 10%. When producing a void-containing yarn with a crystallinity of less than 5%, sufficient metal-like luster and high reflectivity may not be obtained even when drawn, and when it exceeds 15%, a void is contained. When manufacturing a thread | yarn, it may cut | disconnect by extending | stretching.
The degree of crystallinity can be measured by, for example, a refractive index method, an infrared spectroscopy method, an X-ray diffraction method, a hydrometer or a density gradient tube method.

<Average diameter>
The average diameter of the void-containing yarn-producing yarn is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10 μm to 500 μm, more preferably 30 μm to 200 μm. If the average diameter is less than 10 μm, sufficient voids may not be expressed inside the void-containing yarn after stretching, and if it exceeds 500 μm, the stretching tension becomes high, making it difficult to stretch, and containing voids after stretching. It may be difficult to reduce the diameter of the yarn sufficiently.
Here, the average diameter means the average of the maximum diameters in the cross section perpendicular to the extrusion direction of the resin when manufacturing the void-containing yarn manufacturing yarn when the void-containing yarn manufacturing yarn is a circular shape. When the containing yarn-producing yarn is an irregular shape, it means the length of the longest portion in the cross section orthogonal to the resin extrusion direction when producing the void-containing yarn-producing yarn.
The average diameter can be measured by, for example, a photograph of a cross-sectional SEM after embedding a void-containing yarn-producing yarn with an epoxy resin and cutting with a razor or a microtome.

<Reflectance>
The reflectivity (%) of the void-containing yarn-producing yarn is not particularly limited and can be appropriately selected according to the purpose. However, the reflectivity is not usually high and is about 0.1% to 10%. It is.
The reflectance can be measured by, for example, a spectrophotometer, an integrating sphere, or a device that combines a spectrophotometer and an integrating sphere.
The void-containing yarn manufacturing yarn has a low reflectance (%), but by drawing it into a void-containing yarn, it has a metallic luster and a high reflectance (%). A void-containing yarn excellent in aesthetics and design can be obtained.

<Manufacturing method>
The void-containing yarn manufacturing yarn is produced by melt spinning a resin composition containing at least a thermoplastic resin. Specifically, the resin composition is dried, melted with an extruder, melted and discharged from a melt spinneret, cooled, and then wound up.

<< Resin composition >>
The resin composition contains at least a thermoplastic resin, and further contains other components as necessary.
There is no restriction | limiting in particular as a thermoplastic resin, Although it can select suitably according to the objective, It is preferable that it is a polymer which has crystallinity.

-Polymer with crystallinity-
In general, polymers are divided into crystalline polymers and amorphous (amorphous) polymers. A crystalline polymer is not usually 100% crystalline, and includes a crystalline region in which long chain molecules are regularly arranged in a molecular structure and an amorphous region that is not regularly arranged. Contains.
In the present invention, the polymer having crystallinity may include at least a crystalline region in the molecular structure, and a crystalline region and an amorphous region may be mixed, but the crystalline polymer is made of a crystalline polymer. Is particularly preferred.

There is no restriction | limiting in particular as a polymer which has crystallinity, According to the objective, it can select suitably, For example, polyolefin resin, polyamide resin, polyester resin, polyacetal (POM), syndiotactic polystyrene (SPS), polyphenylene Examples thereof include sulfide (PPS), polyether ether ketone (PEEK), liquid crystal polymer (LCP), and fluororesin. These may be used singly or may be used by blending or copolymerizing two or more polymers.
Among these, from the viewpoint of mechanical strength and production, a resin that melts at about 300 ° C. or less is preferable, a polyolefin resin, a polyester resin, or a polyamide resin is more preferable, and a polyester resin is particularly preferable.

The melt viscosity of the crystalline polymer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 50 Pa · s to 1,000 Pa · s, more preferably 70 Pa · s to 750 Pa · s. 80 Pa · s to 450 Pa · s is particularly preferable. A melt viscosity of 50 Pa · s to 1,000 Pa · s is preferred in that the shape of the melt-spun extruded from the nozzle during spinning is stable and it is easy to form a uniform yarn for producing void-containing yarns. . In addition, when the melt viscosity is 50 Pa · s to 1,000 Pa · s, the viscosity of the resin becomes appropriate during spinning, and it is easy to extrude from the nozzle, and the average diameter of the void-containing yarn manufacturing yarn is It is preferable in terms of stability.
Here, the melt viscosity can be measured by, for example, a plate type rheometer, a capillary rheometer, or the like.

The intrinsic viscosity (IV) of the crystalline polymer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.4 to 1.5, preferably 0.6 to 1. 2 is more preferable, and 0.7 to 1.0 is particularly preferable. When the yarn containing the void-containing yarn is used for producing the void-containing yarn, the larger the IV, the easier to express a cavity during drawing, but when the IV is 0.4 to 1.5, Even if it is easy to extrude the molten resin, the resin flow is stable and it is difficult for stagnation to occur, the quality is stable, even when a molten resin filter is installed during spinning, It is difficult to apply a load to the filter, the resin flow is stable, and it is difficult for stagnation to occur. When the void-containing yarn production yarn is used for the production of void-containing yarn, the tensile strength is high, and the drawing tension during drawing Is maintained properly, it can be efficiently stretched, it is easy to stretch uniformly, it is difficult to apply a load to the device, and the product (void-containing yarn) is not easily broken, the physical properties are To increase Preferable in terms of such.
Here, the intrinsic viscosity (IV) can be measured by, for example, an Ubbelohde viscometer.

The melting point (Tm) of the crystalline polymer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 40 ° C to 350 ° C, more preferably 100 ° C to 300 ° C, and more preferably 150 ° C to 260 ° C. is particularly preferred. When the melting point is 40 ° C to 350 ° C, it is easy to maintain the average diameter of the void-containing yarn manufacturing yarn within the temperature range expected for normal use, and special technology required for processing at high temperatures Even if it does not use especially, it is preferable at the point which can manufacture the yarn for void containing yarn manufacture uniformly.
Here, the melting point can be measured by, for example, a differential thermal analyzer (DSC).

The weight average molecular weight of the polymer having crystallinity is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5,000 to 1,000,000, more preferably 10,000 to 800,000. 15,000 to 700,000 is particularly preferable. If the weight-average molecular weight is less than 5,000, when the void-containing yarn-manufacturing yarn is used for the production of void-containing yarn, there is a concern of breaking during stretching, and the weight-average molecular weight exceeds 1,000,000. In some cases, the void-containing yarn-producing yarn is difficult to be stretched, and even if it is stretched, cavities are difficult to develop. On the other hand, when the weight average molecular weight is 15,000 to 700,000, it is preferable from the standpoint that both the ease of drawing the void-containing yarn-producing yarn and the ease of expression of cavities can be achieved.
Here, the weight average molecular weight can be measured by, for example, a gel permeation chromatography (GPC Gel Permeation Chromatography) method.

--- Polyolefin resin--
The polyolefin resin is not particularly limited and can be appropriately selected depending on the purpose. For example, polyethylene, polypropylene (PP), a random copolymer of ethylene and propylene, a block copolymer of ethylene and propylene, And a random copolymer of ethylene and α-olefin (eg, 1-octene, 1-hexene, etc.) and a random copolymer of propylene and α-olefin (eg, 1-octene, 1-hexene, etc.). It is done. These may be used alone or in combination of two or more.
Among these, polypropylene, a random copolymer of ethylene and propylene, and a block copolymer of ethylene and propylene are preferable, and a random copolymer of polypropylene and ethylene and propylene is particularly preferable.

--- Polyamide resin--
There is no restriction | limiting in particular as a polyamide resin, According to the objective, it can select suitably, For example, polycaproamide (nylon 6), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon) 66), polyhexamethylene sebamide (nylon 6/10), polyhexamethylene dodecamide (nylon 6/12), polyundecane adipamide (nylon 11/6), polyundecanamide (nylon 11), Polydodecanamide (nylon 12), polytrimethylhexamethylene terephthalamide, polyhexamethylene isophthalamide (nylon 6I), polyhexamethylene terephthale / isophthalamide (nylon 6T / 6I), polybis (4-aminocyclohexyl) methane dodecamide ( Nylon P CM12), polybis (3-methyl-4-aminocyclohexyl) methane dodecamide (nylon dimethyl PACM12), polymetaxylylene adipamide (nylon MXD6), polyundecamethylene terephthalamide (nylon 11T), polyundecamethylene hexa And hydroterephthalamide (nylon 11T (H)). These may be used alone or in combination of two or more.
Among these, nylon 6, nylon 66, nylon 11, nylon 12, nylon 6/10, nylon 6/12, and nylon 11/6 are preferable, and nylon 6, nylon 66, and nylon 11 are particularly preferable.

--- Polyester resin--
The polyester resin is a polymer having an ester bond obtained by a polycondensation reaction of a dicarboxylic acid component and a diol component as a main bond chain of the main chain.

The dicarboxylic acid component is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, oxycarboxylic acids, and polyfunctional acids. It is done. Among these, aromatic dicarboxylic acids are particularly preferable.

The aromatic dicarboxylic acid is not particularly limited and may be appropriately selected depending on the intended purpose.For example, terephthalic acid, isophthalic acid, diphenyldicarboxylic acid, diphenylsulfone dicarboxylic acid, naphthalenedicarboxylic acid, diphenoxyethanedicarboxylic acid, Examples include 5-sodium sulfoisophthalic acid.
Among these, terephthalic acid, isophthalic acid, diphenyl dicarboxylic acid, preferably naphthalene dicarboxylic acid, terephthalic acid, diphenyl dicarboxylic acid, naphthalene dicarboxylic acid are more preferable.

Examples of the aliphatic dicarboxylic acid include oxalic acid, succinic acid, eicoic acid, adipic acid, sebacic acid, dimer acid, dodecanedioic acid, maleic acid, and fumaric acid.
Examples of the alicyclic dicarboxylic acid include cyclohexyne dicarboxylic acid.
Examples of the oxycarboxylic acid include p-oxybenzoic acid.
Examples of the polyfunctional acid include trimellitic acid and pyromellitic acid.

Geo - The Le component is not particularly limited and may be appropriately selected depending on the intended purpose, for example, aliphatic diols, alicyclic diols, aromatic diols, diethylene glycol, polyalkylene glycol.
Of these, aliphatic diols are particularly preferred.

Examples of the aliphatic diol include ethylene glycol, propane diol, butane diol, 1,4 butylene glycol, pentane diol, hexane diol, neopentyl glycol, triethylene glycol, and the like.
Among these, ethylene glycol, 1,4 butylene glycol, propanediol, and butanediol are particularly preferable.
Examples of the alicyclic diol include cyclohexanedimethanol.
Examples of the aromatic diol include bisphenol A and bisphenol S.

Specific examples of such a polyester resin include PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PTT (polytrimethylene terephthalate), PBT (polybutylene terephthalate), PBN (polybutylene naphthalate) PLA ( Polylactic acid), PBS (polybutylene succinate), PHN (polyhexamethylene naphthalate), PHT (polyhexamethylene terephthalate) and the like.
Among these, PET, PBT, PEN, and PBS are preferable, and PET and PBT are particularly preferable.

The number average molecular weight of the polyester resin is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 12,000 to 40,000, more preferably 18,000 to 40,000, and 18,500 ˜30,000 is particularly preferred. When the number average molecular weight is less than 12,000, the mechanical strength of the void-containing yarn production yarn may be insufficient during spinning. When the number average molecular weight exceeds 40,000, polymerization of the void-containing yarn production yarn is performed. Can be difficult.

The melt viscosity of the polyester resin is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 50 Pa · s to 700 Pa · s, more preferably 70 Pa · s to 500 Pa · s, and more preferably 80 Pa · s to 80 Pa · s. 300 Pa · s is particularly preferable. If the melt viscosity is higher when the void-containing yarn production yarn is used for the production of the void-containing yarn, cavities are likely to appear during drawing, but if the melt viscosity is 50 Pa · s to 700 Pa · s, At this time, it is preferable in that the resin can be easily extruded, the flow of the resin is stable, the retention is difficult to occur, and the quality is stable.
In addition, when the melt viscosity is 50 Pa · s to 700 Pa · s, when the yarn for producing void-containing yarn is used for producing the void-containing yarn, the drawing tension is appropriately maintained at the time of drawing. This is preferable in that it is easy to break and is difficult to break.
Furthermore, when the melt viscosity is 50 Pa · s to 700 Pa · s, it becomes easy to maintain the form of the molten resin extruded from the nozzle during spinning, so that it can be stably molded and the product is less likely to be damaged. , Which is preferable in terms of enhancing physical properties.

In addition, as a polyester resin, the dicarboxylic acid component and the diol component may each be polymerized as a single type to form a polymer, and the dicarboxylic acid component and / or the diol component may be copolymerized as two or more types to form a polymer. It may be formed. Moreover, you may blend and use 2 or more types of polymers as a polyester resin.

In a blend of two or more kinds of polymers, the polymer added to the main polymer has a melt viscosity and an intrinsic viscosity close to that of the main polymer, and the addition amount is smaller when spinning. It is preferable in that the physical properties are enhanced when the resin is extruded, and the resin is easily extruded.

Also, a resin other than the polyester resin may be added to the polyester resin for the purpose of improving the flow characteristics of the polyester resin, controlling the light transmittance, and improving the adhesion with the coating solution.

-Other ingredients-
The other components in the resin composition are not particularly limited and can be appropriately selected depending on the purpose. For example, fillers, heat stabilizers, antioxidants, ultraviolet absorbers, organic lubricants, nucleating agents, Examples include dyes, pigments, flame retardants, mold release agents, dispersants, and coupling agents.
Whether other components contributed to the development of cavities inside the void-containing yarn is whether components other than the polymer having crystallinity (for example, each component described later) are detected in the cavities or at the interface portions of the cavities. It can be determined by how. For example, it can be detected by a scanning electron microscope with an energy-dispersive X-ray analyzer or a microscopic Raman method.

---Antioxidant---
There is no restriction | limiting in particular as antioxidant, According to the objective, it can select suitably, For example, a phenol type compound, a sulfur type compound, a phosphorus type compound etc. are mentioned. These may be used alone or in combination of two or more.
Among these, a known hindered phenol is particularly preferable as the antioxidant. Examples of the hindered phenol include an antioxidant commercially available under trade names such as Irganox 1010 (manufactured by Ciba Specialty Chemicals), Sumilizer BHT, Sumilizer GA-80 (all of which are manufactured by Sumitomo Chemical Co., Ltd.). Etc.
In addition, an antioxidant can be used as a primary antioxidant, and a secondary antioxidant can be used in combination. Examples of the secondary antioxidant include antioxidants marketed under trade names such as Sumilizer TPL-R, Sumilizer TPM, Sumilizer TP-D (all manufactured by Sumitomo Chemical Co., Ltd.). .

---Release agent---
The release agent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include plant waxes such as carnauba wax, animal waxes such as beeswax and lanolin; mineral waxes such as montan wax; paraffins Examples thereof include petroleum waxes such as wax and polyethylene wax; oil-based waxes such as castor oil or derivatives thereof, fatty acids or derivatives thereof, and the like.
Examples of the higher fatty acid derivatives include esters of higher fatty acids such as lauric acid, stearic acid, and montanic acid with monovalent or divalent alcohols.

---Flame retardants---
There is no restriction | limiting in particular as a flame retardant, Although it can select suitably according to the objective, A brominated flame retardant is especially preferable. As brominated flame retardants, organic halogen flame retardants such as high molecular weight organic halogen compounds and low molecular weight organic halogen compounds may be used singly or in combination of two or more. Moreover, you may use a phosphorus flame retardant and an inorganic flame retardant.

<< Melting method >>
There is no restriction | limiting in particular as a method of fuse | melting a resin composition, According to the objective, it can select suitably, For example, the method etc. which heat-melt a resin composition etc. are mentioned.
There is no restriction | limiting in particular as heating temperature, According to the kind etc. of resin in a resin composition, it can select suitably. The molten resin composition becomes a high-temperature viscous liquid and is extruded from the nozzle. Moreover, it is preferable that the molten resin composition is devolatilized as needed.

<< Spinning method >>
Spinning of the melted resin composition is performed by extruding the resin composition from a nozzle into a thread and cooling.

-nozzle-
The nozzle is formed with a large number of small holes, and the resin composition melted through the nozzle is extruded, whereby the resin composition can be formed into a thread.
There is no restriction | limiting in particular as a shape of the hole of a nozzle opening part, According to the objective, it can select suitably, For example, a circular shape, an atypical shape, etc. are mentioned. A variant means various variants that are not circular (perfect circles), such as a gear, ellipse, petal, multileaf, star, C, Y, cross, well, etc. Is mentioned.
The shape of the cross section perpendicular to the extrusion direction of the resin composition of the void-containing yarn manufacturing element yarn is determined by the shape of the hole in the nozzle opening, and thus the shape of the cross-section orthogonal to the drawing direction of the void-containing yarn is also determined. It is determined.

-Extrusion speed-
The yarn for producing a void-containing yarn is an undrawn yarn (UDY). Here, the undrawn yarn refers to a yarn that is in the form of a fiber but has a low degree of molecular chain orientation and can be easily stretched 3 to 4 times as it is and does not return to its original state.
There is no restriction | limiting in particular as extrusion speed at the time of manufacturing an undrawn yarn, Although it can select suitably according to the quantity of a resin composition, a nozzle diameter, etc., Usually, the extrusion speed of about 2,000 m / min or less (Also called spinning speed).

-cooling-
There is no restriction | limiting in particular as a method to cool, According to the objective, it can select suitably, For example, the method of cooling with cooling air, the method of letting the water stored in the water tank, etc. are mentioned.
The cooling temperature (air temperature, water temperature, etc.) is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5 ° C to 60 ° C, more preferably 10 ° C to 40 ° C, and more preferably 15 ° C to 35 ° C. ° C is particularly preferred.
When the cooling temperature is less than 5 ° C., the crystallite size of the (010) plane contained in the void-containing yarn manufacturing yarn is too small, and even if the void-containing yarn manufacturing yarn is stretched as it is, it contains voids. In some cases, the yarn cannot be produced. When the temperature exceeds 60 ° C., the crystallite size of the (010) plane becomes too large, and when used for producing a void-containing yarn, it may be cut during stretching.

<< Winding method >>
There is no restriction | limiting in particular as a winding method, According to the objective, it can select suitably, For example, the method etc. which wind up with a roller are mentioned.

The winding speed (also referred to as “winding speed”) of the void-containing yarn manufacturing yarn (hereinafter sometimes referred to as “undrawn yarn”) is not particularly limited and is appropriately selected according to the purpose. However, 5 m / min to 1,000 m / min is preferable, 20 m / min to 500 m / min is more preferable, and 25 m / min to 200 m / min is particularly preferable. When the winding speed is less than 5 m / min, the void-containing yarn manufacturing yarn may be easily uneven. When the winding speed exceeds 1,000 m / min, the void-containing yarn manufacturing yarn is cut by stress. There is.

When producing a void-containing yarn from a yarn for producing a void-containing yarn, the yarn may be drawn immediately after winding or may be drawn after a certain time at a certain temperature. In the present invention, setting the fixed temperature for a fixed time may be referred to as annealing.
There is no restriction | limiting in particular as temperature and time of annealing, According to the objective, it can select suitably.

<Application>
The void-containing yarn production yarn has a metal-like gloss, high reflectivity and high aesthetics because the crystallite size and crystallinity of the contained crystal nucleus are suitable conditions for the production of void-containing yarn. And can be suitably used for the production of void-containing yarns having excellent design properties.

(Void-containing yarn)
The void-containing yarn of the present invention is a yarn having a metallic luster having a cavity inside, and can be produced by stretching the void-containing yarn-producing yarn of the present invention. Here, the cavity means a vacuum domain or a gas phase domain existing inside the void-containing yarn.
An example of a cross-sectional view of the void-containing yarn is shown in FIGS. 1A and 1B. FIG. 1A is a cross-sectional view of a void-containing yarn when the shape of the hole in the nozzle opening is circular, and FIG. 1B is a cross-sectional view of the void-containing yarn when the shape of the hole in the nozzle opening is irregular. It is. As shown in FIGS. 1A and 1B, the void-containing yarn 43 has a cavity 60 inside the resin portion 61. Moreover, the void containing thread | yarn may have the coating layer 12, as shown to FIG. 2B and FIG. 3B.

<Cavity>
<< Aspect ratio >>
Figures 2A ~ 2C are cases voided yarn is circular, a diagram for explaining the aspect ratio, FIG. 2A is a perspective view of the void-containing yarn, FIG. 2B, the void in Figure 2A FIG. 2C is a cross-sectional view taken along line AA ′ of the containing yarn, and FIG. 2C is a cross-sectional view taken along line BB ′ of the void-containing yarn in FIG. 2A.
Figure 3A ~ 3C are cases voided yarn is atypical, a diagram for explaining the aspect ratio, FIG. 3A is a perspective view of the void-containing yarn, FIG. 3B, voided in Figure 3A FIG. 3C is a cross-sectional view taken along line AA ′ of the yarn, and FIG. 3C is a cross-sectional view taken along line BB ′ of the void-containing yarn in FIG. 3A.

The aspect ratio is the average diameter r (μm) of the cavities 60 in a direction (AA ′ cross section) perpendicular to the surface 43a of the void-containing yarn 43 and perpendicular to the orientation direction of the cavities (FIGS. 2B and 3B). And the average length of the cavities 60 in the orientation direction of the cavities (BB ′ cross section) is L (μm) (see FIGS. 2C and 3C). It means the L / r ratio.

The aspect ratio can be calculated by the following method.
(1) AA ′ cross section and BB ′ cross section are embedded with epoxy resin, cut with a razor or microtome, and examined with a scanning electron microscope. 2B and FIG. 3B) is set so that 50 to 100 cavities are included in the frame.
(2) The number of cavities included in the measurement frame 62 is measured, and the number of cavities included in the measurement frame 62 (see FIGS. 2B and 3B) having a cross section perpendicular to the longitudinal stretching direction is parallel to the longitudinal stretching direction. The number of cavities included in the measurement frame 62 (see FIGS. 2C and 3C) having a simple cross section is n.
(3) The maximum diameter (r _i ) of each cavity included in the AA ′ cross section is measured, the average diameter is r (see FIGS. 2B and 3B), and the measurement frame of the BB ′ cross section is measured. 62 (see FIG. 2C and FIG. 3C), the length (L _i ) of each longest portion of the cavities is measured, and the average length is defined as L.
That is, r and L can be expressed by the following formulas (1) and (2), respectively, whereby the aspect ratio L / r can be calculated.
r = (Σr _i ) / m (1)
L = (ΣL _i ) / n Expression (2)

The aspect ratio is 10 or more, preferably 10 to 100, more preferably 15 to 100, and particularly preferably 20 to 90. If the aspect ratio is less than 10, the reflectivity may be lowered, and if it exceeds 100, the mechanical properties may be lowered. When the aspect ratio is 10 to 100, it is advantageous from the viewpoint of coexistence of various properties such as reflection and heat insulation and mechanical properties.

The orientation direction of the cavities usually indicates the stretching direction. Usually, since longitudinal stretching is performed along the direction in which the void-containing yarn-producing yarn flows during production, the direction of longitudinal stretching becomes the orientation direction of the cavities.

<< Cavity occupied area >>
In the void-containing yarn, the cross-sectional area of the void-containing yarn in an arbitrary cross section orthogonal to the length direction (stretching direction) is a (μm ² ), and the cross-sectional area of the cavity in the cross section is A (μm ² ). In this case, the average of these ratios (A / a) is preferably 0.05 or more and 0.4 or less.
Each cross-sectional area in a cross section can be measured by, for example, an image of an optical microscope or an electron microscope.

In the void-containing yarn, the product of the average number P of cavities in the thickness direction and the refractive index difference ΔN between the resin part having crystallinity and the cavities is preferably 2 or more, more preferably 2.5 or more. 3 or more is particularly preferable. If the product of ΔN and P is less than 2, the reflectivity may decrease.

Here, the number of cavities in the thickness direction refers to a plane perpendicular to the surface 43a of the void-containing yarn 43 and including a direction perpendicular to the orientation direction of the cavities (cross section AA ′ in FIGS. 2A and 3A, That is, in the cross section in the thickness direction, this means the number of cavities 60 included in the thickness direction.
The average number P of voids in the thickness direction in the void-containing yarn is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5 or more, more preferably 10 or more, and 15 or more. Is particularly preferred.
The number of cavities in the thickness direction can be measured by, for example, images from an optical microscope or an electron microscope. On these images, a plurality of straight lines are drawn in parallel in the thickness direction and exist on the plurality of straight lines. The average number P can be obtained by calculating the average value of the number of cavities.

Further, the resin part 61 having crystallinity refers to a part other than the cavity (part made of a resin having crystallinity) in the void-containing yarn 43 (shaded part in FIGS. 1A and 1B).
Refractive index difference ΔN between the resin portion and the cavity having a crystallinity in the void-containing yarn is specifically a refractive index of the resin portion as N1 having a refractive index of the cavity upon the N2, N1 and N2 ΔN (= N1−N2), which is the difference between
The refractive indexes N1 and N2 of the resin part having a crystallinity and the cavity can be measured by, for example, an Abbe refractometer.

As described above, the void-containing yarn has various excellent characteristics in, for example, metallic luster, reflectivity, concealability, heat insulation, cushioning property and the like by having a cavity inside. Yes. That is, characteristics such as metallic luster, reflectivity, concealing property, heat insulating property, and cushioning property can be adjusted by changing the aspect of the void inside the void-containing yarn.

<Average diameter>
The average diameter of the void-containing yarn is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5 μm to 200 μm, more preferably 5 μm to 100 μm, and particularly preferably 5 μm to 50 μm. If the average diameter of the void-containing yarn is less than 5 μm, the void-containing yarn may be cut at the time of drawing, or a sufficient cavity may not be formed, and a sufficient metallic luster and high reflectance may not be obtained. If the ratio is more than 50%, the ratio of the cavities is too high, and the color becomes worse, and the texture becomes stiff, so that the texture may be inferior when the cloth is further woven. For example, when used for a composite material such as FRP (fiber reinforced plastic), it may be difficult to obtain a desired form. On the other hand, when the average diameter of the void-containing yarn is in a particularly preferable range, it is advantageous in that a sufficient metallic luster and high reflectance can be obtained.
The average diameter of the void-containing yarn means the average of the maximum diameter in the cross section in the direction orthogonal to the length direction of the void-containing yarn when the void-containing yarn is circular, and the void diameter when the void-containing yarn is irregular. The length of the longest part in the cross section in the direction orthogonal to the length direction of a containing thread | yarn is said.
Here, for example, after the void-containing yarn is cut with a razor or a microtome, the diameter of the void-containing yarn can be measured by a photograph of a cross-sectional SEM.

<Reflectance>
The reflectance (%) of the void-containing yarn is literally the reflectivity when the void-containing yarn is woven or knitted into a cloth shape.
The reflectance (%) is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 30% or more, more preferably 50% or more, and particularly preferably 60% or more. If the reflectance is less than 30%, the aesthetics and design of the void-containing yarn may be deteriorated. In addition, since the one where a reflectance is higher is excellent in the aesthetics and design nature by metal-like luster, the upper limit has no critical significance.
The reflectance can be measured by, for example, a spectrophotometer, an integrating sphere, or the like.

<Density>
The density of the void-containing yarn is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1.20 g / cm ³ or ^{less, 0.5g / cm 3 ~ 1.05g /} cm 3 Gayori preferable.
As a method for measuring the density, for example, when the density is 1.05 g / cm ³ or more, a 5 mm void-containing yarn can be measured by the density gradient tube method. When the density is less than 1.05 g / cm ³ , for example, in the method described in JIS K6920, for example, a weighted yarn-containing pycnometer (25 mL) is accurately weighed with an electronic balance and weighing about 1 g of void-containing yarn. can do.

<Coating layer>
The void-containing yarn may have a coating layer.
The material of the coating layer is not particularly limited as long as the effects of the invention are not impaired, and can be appropriately selected according to the purpose. For example, hydrophobic polymers such as polyolefins and fluororesins, UV curable polymers, etc. Is mentioned. Thereby, especially water resistance, hydrolysis resistance, tensile elastic modulus, bending resistance, etc. can be improved.
Moreover, the coating layer may contain a dye. For example, by covering a void-containing yarn with a polymer containing a dye such as black or blue, a yarn having a metallic luster such as metallic black or metallic blue can be obtained, and the range of uses of the void-containing yarn is widened. Is preferable.
The thickness of the coating layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 3% to 30% of the radius in the cross section (including the resin part and the cavity part) of the void-containing yarn. If the thickness of the coating layer is less than 3% of the radius in the cross section of the void-containing yarn, sufficient mechanical properties may not be imparted. If the thickness exceeds 30% of the radius in the cross section of the void-containing yarn, The suppleness and feel may be insufficient, and the productivity may be reduced.

<Manufacturing method>
The void-containing yarn can be produced by drawing the yarn for producing the void-containing yarn of the present invention.

<< Drawing method >>
The method for drawing the void-containing yarn-producing yarn is not particularly limited and can be appropriately selected according to the purpose. In any drawing method, the direction in which the void-containing yarn-producing yarn flows in the production process. It is preferable that the stretching is performed along the thread, and it is more preferable that the void-containing yarn-producing yarn is stretched so that necking is expressed.
Here, necking means a constriction-like deformation that occurs during drawing of a void-containing yarn manufacturing yarn that is an undrawn raw yarn (Polymer Engineering Lecture 6 Edited by Plastics Society of Polymer Science, published by Jijin Shoin, (Refer to the first edition issued on April 25, 1966). In addition, a phenomenon in which the void-containing yarn-producing yarn is deformed while being constricted at the time of drawing and the cross-section is sharply reduced at the constricted portion is defined as “necking has occurred”.

FIG. 4 is a diagram illustrating an example of a stretching method. As shown in FIG. 4, the void-containing yarn manufacturing yarn 5 is inserted into, for example, a heating furnace 30 adjusted to 25 ° C. to 150 ° C., and a tensile force is applied by adding a difference in rotational speed between the nip rolls 41 and 42. The void-containing yarn 43 having a cavity is produced by stretching by applying and causing necking. In some cases, the same void-containing yarn 43 can be produced simply by heating the nip roll 41 (25 ° C. to 150 ° C.) except for the heating furnace 30. In FIG. 4, 31 represents an annealing furnace, and 32 represents a winding device.
Specifically, the void-containing yarn 43 of the present invention is formed by stretching the void-containing yarn-producing yarn 5 (undrawn yarn) and forming a cavity having a major axis in the drawing direction therein. can get.

The reason why the cavities are formed by stretching is that the polymer having at least one crystallinity constituting the void-containing yarn-producing yarn has microcrystals that are difficult to stretch, and the microcrystals that are difficult to stretch during stretching. This is because the amorphous resin that is not crystallized between other hard-to-stretch microcrystals is peeled and stretched in such a way that it is torn off at the interface with the microcrystalline phase or inside the amorphous phase. It is considered that a cavity is formed as a cavity forming source.
Such void formation by stretching is possible not only when there is only one kind of crystalline polymer but also when two or more kinds of crystalline polymers are blended or copolymerized. is there.

Generally, in stretching, the number of stretching stages and the stretching speed can be adjusted by the combination of rolls and the speed difference between the rolls.
The number of stages of longitudinal stretching is not particularly limited as long as it is one or more, and can be appropriately selected according to the purpose.

In particular, recently, it has been studied to further reduce the diameter of the yarn in order to give the yarn functionality, but in order to obtain a void-containing yarn having a further reduced diameter, the fiber structure is not changed. It is also possible to adopt a fluid stretching process or the like that makes the diameter only ultrafine. By such a method, the average diameter of the void-containing yarn can be reduced to an ultrafine diameter of 10 μm or less.

-Stretching speed-
The stretching speed of stretching is not particularly limited as long as the effect of the present invention is not impaired, and can be appropriately selected according to the purpose, but is preferably 50 m / min to 5,000 m / min, preferably 100 m / min to 1 1,000 m / min is more preferable. If the stretching speed is less than 50 m / min, sufficient necking is less likely to occur, and the voids are not uniformly formed, resulting in uneven thickness and metal-like gloss. When the drawing speed exceeds 5,000 m / min, the yarn is liable to be broken, the yield is lowered, and the equipment becomes complicated and costs may be increased in order to maintain handling properties.
On the other hand, when the stretching speed is 50 m / min or more, it is preferable in that sufficient necking is easily expressed. Also, when the stretching speed is 5,000 m / min or less, the yarn is not easily broken and uniform stretching is easy, and in particular, a large-scale stretching device for high-speed stretching is not required and the cost is reduced. It is preferable in that it can be performed.

-Stretching temperature-
The temperature during stretching is not particularly limited and can be appropriately selected according to the purpose.
When the stretching temperature is T (° C) and the glass transition temperature is Tg (° C),
(Tg-30) ≦ T ≦ (Tg + 50)
It is preferable to stretch at a stretching temperature T (° C.) in the range indicated by
(Tg−25) ≦ T ≦ (Tg + 45)
It is more preferable to stretch at a stretching temperature T (° C.) in the range indicated by
(Tg−20) ≦ T ≦ (Tg + 40)
It is particularly preferable to stretch at a stretching temperature T (° C.) in the range indicated by

In general, the higher the stretching temperature (° C.), the lower the stretching tension, and the easier it can be stretched. However, when the stretching temperature (° C.) is {glass transition temperature (Tg) +50} ° C. or less, cavities are formed. This is preferable in that the volume ratio is high and the aspect ratio tends to be in a preferable range. Further, it is preferable that the stretching temperature (° C.) is {glass transition temperature (Tg) −30} ° C. or higher from the viewpoint that a cavity is sufficiently developed.
Here, the stretching temperature T (° C.) can be measured with a non-contact thermometer. The glass transition temperature Tg (° C.) can be measured by a differential thermal analyzer (DSC).

In addition, the void-containing yarn after drawing may be further subjected to heat shrinkage by applying heat or treatment such as tension for the purpose of shape stabilization.

<Yield>
The yield of the void-containing yarn having a metallic luster obtained by stretching the void-containing yarn production yarn of the present invention is set according to the business purpose, profitability, etc., and is not particularly limited.
The yield is, for example, the length remaining after sampling the void-containing yarn over 100 m after 5 seconds after stretching starts, and by cutting the transparent to milky white portion by visual inspection for the entire length. (M) is (A), and can be calculated from the following calculation formula (I).
Yield of void-containing yarn (%) = (A) / 100 × 100 Formula (I)

<Application>
Since the void-containing yarn is produced using the void-containing yarn-producing yarn of the present invention, the void-containing yarn is uniformly stretched. Therefore, the void-containing yarn has a metallic luster and is excellent in aesthetics and design. It is a thing. The void-containing yarn contains voids that do not communicate with each other, and is light and excellent in heat insulation and light shielding properties, so that it can be suitably used for various applications such as clothing, building materials, medical materials, electronic equipment members, and electric vehicle members. it can.

Hereinafter, the present invention will be specifically described with reference to examples of the present invention, but the present invention is not limited to these examples.

Example 1
<Preparation of void-containing yarn production yarn (undrawn yarn)>
A polybutylene terephthalate (PBT) resin (manufactured by Wintech Polymer Co., Ltd.) having an intrinsic viscosity (IV) of 0.72 and a glass transition temperature (Tg) of 37 ° C. is melt-spun (single-screw melt extruder having a screw diameter of 35 mmφ (Co., Ltd.) The yarn for producing the void-containing yarn of Example 1 was produced by melting at 255 ° C. using Chubu Chemical Machinery Co., Ltd., and cooling and solidifying through water. Was wound at a winding speed of 35 m / min, and the shape of the hole in the nozzle opening of the melt spinning machine was substantially circular, and the water temperature for solidifying the void-containing yarn manufacturing yarn was 30 ° C. Set to.

<Evaluation of yarn for producing void-containing yarn>
By the method shown below, the crystallite size, crystallinity, average diameter of the void-containing yarn-producing yarn, and reflectance were measured on the crystal plane of the (010) plane of the void-containing yarn-producing yarn. The results are shown in Table 2.

-Measurement of crystallite size of crystal plane of (010) plane inside void-containing yarn manufacturing yarn-
Using an X-ray diffractometer (RINT-TTR III, manufactured by Rigaku Corporation), the measurement was performed by arranging the yarns on a glass sample holder so as to have a width of 25 mm. A peak separation between a crystal peak and an amorphous peak (2θ = 21 °) was performed. Using the full width at half maximum of each peak, the crystallite size (nm) of the crystal plane of the (010) plane inside the void-containing yarn manufacturing yarn is obtained from the Scherrer equation (Scherrer coefficient = 0.9). It was.

-Measurement of crystallinity-
The crystallinity (%) of the void-containing yarn-producing yarn was measured by a density gradient tube method using a carbon tetrachloride / heptane mixed solution.

-Measurement of average diameter of yarn containing void-containing yarn-
The average diameter (μm) of the void-containing yarn-producing yarn is the maximum diameter of the cross-section SEM photograph after cutting a section perpendicular to the extrusion direction of the resin when producing the void-containing yarn-producing yarn. Was measured and the average value was calculated.

-Measurement of reflectance-
Spectrophotometer (V-570, manufactured by JASCO Corporation) and an integrating sphere (ILN-472, manufactured by JASCO Corporation) void containing yarn light reflectance (%) was measured at a wavelength of 550nm using.

<Production of void-containing yarn>
The drawing of the void-containing yarn-producing yarn was performed using two sets of drawing nip rollers and a plate heater installed therebetween. That is, the void-containing yarn manufacturing yarn 1 is uniaxially stretched by a nip roller (with a low-speed nip roller) at a speed of 35 m / min and a nip roller (high-speed nip roller) at a speed of 195 m / min in a heated atmosphere at 39 ° C. (Magnification: 5.5 times). At this time, the void-containing yarn-producing yarn was stretched while exhibiting necking. This produced the void-containing yarn of Example 1.

<Evaluation of void-containing yarn>
The yield of void-containing yarn was calculated by the method described below, and the average diameter, reflectance, and aspect ratio of the void-containing yarn were measured. In addition, the sensory evaluation of the metallic luster of the void-containing yarn was performed by the method described below. The results are shown in Table 2.

-Calculation of yield of void-containing yarn-
The yield of the void-containing yarn was calculated from the following calculation formula (I).
Yield of void-containing yarn (%) = (A) / 100 × 100 Formula (I)
However, in the formula (I), (A) indicates that the void-containing yarn is sampled over 100 m after the elapse of 5 seconds after the neck stretching has started, and the entire length is transparent to milky white by visual inspection. Indicates the length (m) remaining after excision. The yield is preferably 70% or more from the viewpoint of continuous productivity.

-Measurement of mean diameter of void-containing yarn-
The average diameter (μm) of the void-containing yarn was obtained by measuring the diameter with a photograph of the cross-section SEM after cutting a cross section perpendicular to the drawing direction of the void-containing yarn with a razor and calculating the average value of the maximum diameter.

-Measurement of aspect ratio-
A cross section perpendicular to the surface of the void-containing yarn and perpendicular to the longitudinal stretching direction (see FIG. 2B), and a cross section perpendicular to the surface of the void-containing yarn and parallel to the longitudinal stretching direction (see FIG. 2C), The sample was cut with a razor and examined with a scanning electron microscope at an appropriate magnification of 300 to 3,000, and a measurement frame 62 (see FIG. 2B) was set in each cross-sectional photograph. The measurement frame 62 was set so that 50 to 100 cavities were included in the measurement frame.
Next, the number of cavities included in the measurement frame 62 is measured, and the number of cavities included in the measurement frame 62 (see FIG. 2B) having a cross section perpendicular to the longitudinal stretching direction is m, and the cross section parallel to the longitudinal stretching direction. The number of cavities included in the measurement frame 62 (see FIG. 2C) is n.
Then, the cross section of the measurement frame 62 perpendicular to the longitudinal stretching direction maximum diameter of each one of the cavities included in (see FIG. 2B) to (r _i) was measured, and the average diameter of the r. Further, the length (L _i ) of each longest portion of the cavities included in the measurement frame 62 (see FIG. 2C) having a cross section parallel to the longitudinal stretching direction was measured, and the average length was defined as L.
That is, r and L can be represented by the following formulas (1) and (2), respectively.
r = (Σr _i ) / m (1)
L = (ΣL _i ) / n Expression (2)
Then, L / r was calculated as an aspect ratio.

-Sensory evaluation of metallic luster-
Twenty void-containing yarns after stretching were collected, and the samples that were closely arranged on the black plate and attached were used as evaluation samples. On the other hand, 20 wires made of AL (φ0.12 mm) were prepared as a reference sample in the same manner as the void-containing yarns, which were closely arranged and pasted on a black plate.
These samples were visually compared by five panelists of metal-like glossy yarn under a white fluorescent lamp. At this time, the illuminance on the sample surface was changed from 1,300 Lx to 1,500 Lx. The illuminance was measured with a pocket illuminometer (ANA-F9, manufactured by Tokyo Koden Co., Ltd.).
The number of panelists who judged that the metal-like gloss of the void-containing yarn was equal to or higher than that of the reference sample was rated (1-5). That is, the higher the score, the better the metallic luster. The results are shown in Table 2. Table 2 also shows the appearance and state at this time.

(Examples 2 to 6 and Comparative Examples 1 to 9)
In the production of the void-containing yarn production yarn (undrawn yarn) of Example 1, the resin and melt spinning conditions were in accordance with the conditions of Examples 2 to 6 and Comparative Examples 1 to 9 described in Table 1 below. Except for the above, the void-containing yarn production yarns of Examples 2 to 6 and Comparative Examples 1 to 9 were produced in the same manner as in Example 1, and each void-containing yarn production yarn was produced in the same manner as in Example 1. The crystallinity of the yarn, the crystallite size of the (010) plane, the average diameter of the void-containing yarn manufacturing yarn, and the reflectance were measured. The results are shown in Table 2.
Polybutylene terephthalate (PBT) resin having an intrinsic viscosity (IV) of 0.69 and a glass transition temperature (Tg) of 36 ° C. is manufactured by Daicel Chemical Industries, Ltd., and has an intrinsic viscosity (IV) of 0.7 and a glass transition temperature (Tg). A polyethylene terephthalate (PET) having a polyethylene terephthalate (PET) of 75 ° C. and an intrinsic viscosity (IV) of 0.76 and a glass transition temperature (Tg) of 75 ° C. was manufactured by FUJIFILM Corporation.

Further, in the production of the void-containing yarn of Example 1, the void-containing yarn production yarns produced in Examples 2 to 6 and Comparative Examples 1 to 9 were used, and Examples 2 to 6 and Comparative Examples described in Table 1 below were used. Except that the conditions 1 to 9 were followed, the void-containing yarns of Examples 2 to 6 and Comparative Examples 1 to 9 were produced in the same manner as in Example 1, and the void-containing yarns were produced in the same manner as in Example 1. Calculation of the yield of the yarn, measurement of the average diameter, reflectance and aspect ratio of the void-containing yarn, and sensory evaluation of the metallic luster were performed. The results are shown in Table 2.
Comparative Examples 1 and 5 showed no metallic luster, Comparative Examples 2 and 4 showed white turbidity but no metallic luster, and Comparative Examples 3 and 6-9 were subjected to stretching. Since the yarns were cut, void-containing yarns having a metallic luster could not be stably obtained when the yarns of Comparative Examples 1 to 9 were used.

The production conditions of the void-containing yarn production yarns and the void-containing yarns of Examples 1 to 6 and Comparative Examples 1 to 9 are summarized in Table 1 below. The evaluation results of Examples 1 to 6 and Comparative Examples 1 to 9 are shown in Table 2 below.
FIG. 5 is a plot of the relationship between the yield of the void-containing yarns of Examples 1 to 6 and Comparative Examples 1 to 9 and the crystallite size of the (010) plane of the crystal nucleus of the void-containing yarn-producing yarn. The scatter diagram was shown. FIG. 6 is a scatter diagram in which the relationship between the yield of void-containing yarns of Examples 1 to 6 and Comparative Examples 1 to 9 and the crystallinity of the yarn for producing void-containing yarns is plotted.

From the results in Table 2 and FIGS. 5 to 7, the void-containing yarn can be stably and efficiently produced by drawing the void-containing yarn production yarn of Examples 1 to 6, and the void-containing yarn production yarn is drawn. It was found that the void-containing yarn obtained in this way had a metallic luster, high reflectivity, and excellent aesthetics and design.
On the other hand, from Comparative Examples 1 to 9, when the crystallite size of the (010) plane crystal plane is less than 2 nm, a void-containing yarn cannot be obtained. It was found that the wire was broken when it was stretched. Further, when the degree of crystallinity is 5% or less, a void-containing yarn cannot be obtained. When the degree of crystallinity exceeds 15%, the void-containing yarn manufacturing strand may be broken or extreme unevenness may occur. It was found to occur.

Since the void-containing yarn manufacturing yarn according to the present invention is suitable for the production of void-containing yarns, the crystallite size and crystallinity of the internal crystal nucleus are suitable for the production of void-containing yarns. It is suitable for stably and efficiently producing a void-containing yarn having excellent properties and design properties.
Since the void-containing yarn is produced using the void-containing yarn-producing yarn of the present invention, the void-containing yarn is uniformly stretched. Therefore, the void-containing yarn has a metallic luster and is excellent in aesthetics and design. It is a thing. The void-containing yarn contains voids that do not communicate with each other, and is light and excellent in heat insulation and light shielding properties, so that it can be suitably used for various applications such as clothing, building materials, medical materials, electronic equipment members, and electric vehicle members. it can.

DESCRIPTION OF SYMBOLS 5 Element yarn for void containing yarn 12 Coating layer 30 Heating furnace 31 Annealing treatment furnace 32 Winding device 41 Nip roll 42 Nip roll 43 Void containing yarn 43a Surface of void containing yarn 60 Cavity 61 Resin part 62 Measurement frame

Claims

A void-containing yarn-manufacturing yarn for producing a void-containing yarn having an independent cavity inside,
When stretched, the cavities are formed in a state of being oriented in the stretching direction inside, the average length of the cavities is L (μm), and the average diameter of the cavities in the direction orthogonal to the orientation direction of the cavities is L / r ratio when r (μm) is 10 or more,
A void-containing yarn-producing yarn characterized by including a crystal nucleus having a crystallite size of 2 nm to 5 nm on a (010) plane and a crystallinity of 5% to 15%.
2. The void-containing yarn manufacturing yarn according to claim 1, wherein the average diameter is 10 μm to 500 μm.
3. A void-containing yarn manufacturing yarn according to claim 1, comprising a crystalline polymer.
4. The void-containing yarn-producing element according to claim 1, wherein the reflectance is 0.1% to 10%, and the reflectance of the void-containing yarn obtained by stretching is 30% to 90%. yarn.
A void-containing yarn obtained by drawing the yarn for producing the void-containing yarn according to any one of claims 1 to 4,
Inside, the cavity is formed in the state of being oriented in the stretching direction, the average length of the cavity is L (μm), and the average diameter of the cavity in the direction orthogonal to the orientation direction of the cavity is r (μm). A void-containing yarn having an L / r ratio of 10 or more.