JP2012140721A - Raw yarn for producing void-containing yarn and void-containing yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide raw yarn for producing void-containing yarn including a fine crystal nucleus that meets conditions for stably and efficiently producing void-containing yarn with metallic gloss, high reflectance and excellent aesthetic property and design, by extension.SOLUTION: When raw yarn for producing void-containing yarn having an independent cavity inside is extended, the cavity is formed inside in an aligned state in the extension direction, and if the average length of the cavity is L (μm) while the average diameter of the cavity in the direction orthogonal to the alignment direction of the cavity is r (μm), the L/r ratio is 10 or more, and the raw yarn for producing void-containing yarn includes a crystal nucleus with the crystallite size in a crystal face of a (010) plane of 2-5 nm and has a degree of crystallization of 5-15%.

Description

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

In recent years, various efforts have been made to improve the functionality, aesthetics, and design of fibers. For example, by changing the cross-sectional shape of the fiber, improving water absorption, or modifying the polymer, the lightness is improved, the fibrillation is improved, or the deep color is improved (for example, , 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. Therefore, the quality of such fibers largely depends on the properties of the yarn for producing the yarn, that is, the crystallite size and crystallinity of the crystal nucleus contained in the yarn.
However, in the production of fibers shown in Patent Document 3 and the like so far, the type of resin used as a raw material and stretching conditions have been studied, but the properties of the yarn have not been sufficiently studied, and the wire breaks during stretching. Thus, there are problems such that stable stretching cannot be performed and sufficient reflectance cannot be obtained even when stretching.

  Therefore, in order to stably produce a yarn having a metallic luster, high reflectivity and excellent aesthetics and design, it is desired to improve the quality of the yarn used for the production of the yarn. .

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

  An object of the present invention is to solve the above-described problems and achieve the following objects. 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 as a result, obtained the following findings. That is, the quality of the reflectivity and the like 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-producing yarn for producing a void-containing yarn having an independent cavity inside, and when drawn, the cavity is formed in an oriented state in the drawing direction, The L / r ratio 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) is 10 or more, (010) A void-containing yarn-producing yarn characterized by including crystal nuclei having a crystallite size of 2 nm to 5 nm in a plane and having a crystallinity of 5% to 15%.
<2> The void-containing yarn manufacturing yarn according to <1>, wherein the average diameter is 10 μm to 500 μm.
<3> The void-containing yarn-producing yarn according to any one of <1> to <2>, which is made of a crystalline polymer.
<4> The reflectance 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 a void-containing yarn.
<5> Any one of <1> to <4>, wherein the crystallite size of the crystal plane of the (010) plane includes a crystal nucleus of 2.5 nm to 3.5 nm and the crystallinity is 7% to 10% A void-containing yarn production yarn according to any one of the above.
<6> A void-containing yarn obtained by drawing the void-containing yarn-producing yarn according to any one of <1> to <5>, wherein the cavity is oriented in the drawing direction inside. 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). This is a void-containing yarn characterized by the above.
<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 view for explaining the aspect ratio, and is a B-B ′ sectional view 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 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. 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 a 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. Is particularly preferred. When the crystallite size of the crystal plane 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. When it exceeds 5 nm, the crystallite size is too large, and when producing a void-containing yarn, it may be cut by stretching.
The crystallite size of the crystal plane of the (010) plane can be measured by, for example, X-ray diffraction.

<Crystallinity>
The degree of crystallinity of the void-containing yarn-producing yarn is 5% to 15%, preferably 5% to 12%, and more preferably 7% to 10%. When the degree of crystallinity is less than 5%, it may not be possible to obtain a sufficient metal-like gloss or high reflectance even when stretched when producing a void-containing yarn. When manufacturing a containing thread | yarn, it may cut | disconnect by extending | stretching.
The 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>
There is no restriction | limiting in particular as an average diameter of the said yarn for void containing thread | yarn manufacture, Although it can select suitably according to the objective, 10 micrometers-500 micrometers are preferable, and 30 micrometers-200 micrometers are more preferable. When the average diameter is less than 10 μm, sufficient voids may not be expressed inside the void-containing yarn after stretching. When the average diameter exceeds 500 μm, stretching tension becomes high and stretching becomes difficult. The contained yarn may be difficult to reduce in diameter sufficiently.
Here, when the void-containing yarn-producing yarn is a circular shape, the average diameter is the average of the maximum diameters in a cross section perpendicular to the extrusion direction of the resin when producing the void-containing yarn-producing yarn. In other words, when the void-containing yarn-producing yarn is an irregular shape, it means the length of the longest portion in the cross section perpendicular to the extrusion direction of the resin when the void-containing yarn-producing yarn is produced.
The average diameter can be measured by, for example, a photograph of a cross-sectional SEM after embedding the 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 0.1% to 10%. Degree.
The reflectance can be measured by, for example, a spectrophotometer or 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 (%). Thus, a void-containing yarn excellent in aesthetics and design can be obtained.

<Manufacturing method>
The void-containing yarn-producing 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 said thermoplastic resin, Although it can select suitably according to the objective, It is preferable that it is a polymer which has crystallinity.

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

The polymer having crystallinity is not particularly limited and may be appropriately selected depending on the intended purpose. For example, polyolefin resin, polyamide resin, polyester resin, polyacetal (POM), syndiotactic polystyrene (SPS), Examples include polyphenylene 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. When the melt viscosity is 50 Pa · s to 1,000 Pa · s, the shape of the melt-spun extruded from the nozzle during spinning is stable, and it is easy to form a uniform yarn containing void-containing yarn. preferable. 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. This is preferable in that the diameter is stable.
Here, the melt viscosity can be measured by, for example, a plate type rheometer, a capillary rheometer, or the like.

There is no restriction | limiting in particular as intrinsic viscosity (IV: Intrinsic Viscosity) of the polymer which has the said crystallinity, Although it can select suitably according to the objective, 0.4-1.5 are preferable, 0.6-1 .2 is more preferable, and 0.7 to 1.0 is particularly preferable. Where the IV is larger, when the void-containing yarn production yarn is used for the production of void-containing yarn, it is easy to express cavities at the time of drawing, but the IV is 0.4 to 1.5, This is because it is easy to extrude the molten resin during spinning, the flow of the resin is stable and it is difficult for stagnation to occur, the quality is stable, and a molten resin filter is installed during spinning. However, 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 manufacturing yarn is used for manufacturing void-containing yarn, the tensile strength is increased, Since the drawing tension is properly maintained at the time of drawing, it is possible to draw efficiently, thereby making it easy to draw uniformly, making it difficult for the device to be loaded, and further making the product (void-containing yarn) difficult to break. And Sex increases that, preferable in terms of such.
Here, the intrinsic viscosity (IV) can be measured by, for example, an Ubbelohde viscometer.

There is no restriction | limiting in particular as melting | fusing point (Tm) of the polymer which has the said crystallinity, Although it can select suitably according to the objective, 40 to 350 degreeC is preferable, 100 to 300 degreeC is more preferable, 150 degreeC ˜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-producing yarn within a temperature range expected for normal use, and specially required for processing at a high temperature Even if it does not use especially a technique, it is preferable at the point which can manufacture the said yarn for void containing yarn manufacture uniformly.
Here, the melting point can be measured by, for example, a differential thermal analyzer (DSC).

There is no restriction | limiting in particular as a weight average molecular weight of the polymer which has the said crystallinity, Although it can select suitably according to the objective, 5,000-1,000,000 are preferable and 10,000-800,000 are More preferred is 15,000 to 700,000. 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 is 1,000,000. If it exceeds 000, the void-containing yarn-producing yarn may be difficult to be stretched, and even if it is stretched, cavities may be difficult to develop. On the other hand, when the weight average molecular weight is 15,000 to 700,000, it is preferable from the viewpoint that both the ease of drawing the void-containing yarn-producing yarn and the ease of expression of voids can be achieved.
Here, the weight average molecular weight can be measured, for example, by a gel permeation chromatography (GPC Gel Permeation Chromatography) method.

--- Polyolefin resin--
The polyolefin resin is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include polyethylene, polypropylene (PP), a random copolymer of ethylene and propylene, and a block copolymer of ethylene and propylene. Random copolymers of ethylene and α-olefin (eg, 1-octene, 1-hexene, etc.), random copolymers of propylene and α-olefin (eg, 1-octene, 1-hexene, etc.) Can be mentioned. 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 said 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 terephthalate / isophthalamide (nylon 6T / 6I), polybis (4-aminocyclohexyl) methane dodecamide (Nairro PACM12), polybis (3-methyl-4-aminocyclohexyl) methane dodecamide (nylon dimethyl PACM12), polymetaxylylene adipamide (nylon MXD6), polyundecamethylene terephthalamide (nylon 11T), polyundecamethylenehexa 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. Can be mentioned. 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 , 5-sodium sulfoisophthalic acid and the like.
Among these, terephthalic acid, isophthalic acid, diphenyldicarboxylic acid, and naphthalenedicarboxylic acid are preferable, and terephthalic acid, diphenyldicarboxylic acid, and naphthalenedicarboxylic 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.

There is no restriction | limiting in particular as said diol component, According to the objective, it can select suitably, For example, aliphatic diol, alicyclic diol, aromatic diol, diethylene glycol, polyalkylene glycol etc. are mentioned.
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.

  There is no restriction | limiting in particular as a number average molecular weight of the said polyester resin, Although it can select suitably according to the objective, 12,000-40,000 are preferable, 18,000-40,000 are more preferable, 18, 500 to 30,000 is particularly preferred. When the number average molecular weight is less than 12,000, the mechanical strength of the void-containing yarn-producing yarn may be insufficient during spinning. When the number-average molecular weight exceeds 40,000, the void-containing yarn-producing yarn is Yarn polymerization can be difficult.

There is no restriction | limiting in particular as melt viscosity of the said polyester resin, Although it can select suitably according to the objective, 50 Pa.s-700 Pa.s are preferable, 70 Pa.s-500 Pa.s are more preferable, 80 Pa.s ˜300 Pa · s is particularly preferred. When the void-containing yarn production yarn is used for the production of void-containing yarn, the higher the melt viscosity, the easier to express cavities during drawing, but the melt viscosity is 50 Pa · s to 700 Pa · s. In spinning, the resin is easy to extrude, and the resin flow is stable and the retention is difficult to occur, which is preferable in terms of stable quality.
Further, when the melt viscosity is 50 Pa · s to 700 Pa · s, when the void-containing yarn production yarn is used for producing the void-containing yarn, the draw tension is appropriately maintained at the time of drawing. It is preferable in that it can be easily stretched and is difficult to break.
Furthermore, when the melt viscosity is 50 Pa · s to 700 Pa · s, it is easy to maintain the form of the molten resin extruded from the nozzle during spinning, and it is possible to stably form or the product is difficult to break. It is preferable in terms of improving physical properties.

  In addition, as the polyester resin, the dicarboxylic acid component and the diol component may each be polymerized to form a polymer, and the dicarboxylic acid component and / or the diol component may be a combination of two or more. It may be polymerized to form a polymer. Further, as the polyester resin, two or more kinds of polymers may be blended and used.

  In the blend of two or more kinds of polymers, the polymer added to the main polymer is closer to the melt viscosity and the intrinsic viscosity than the main polymer, and the amount added is smaller when spinning. It is preferable in that the physical properties are increased during extrusion of the molten resin, and the extrusion becomes easy.

  In addition, 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 light transmittance, and improving the adhesion with the coating solution.

-Other ingredients-
The other components in the resin composition are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include fillers, heat stabilizers, antioxidants, ultraviolet absorbers, organic lubricants, and cores. Agents, dyes, pigments, flame retardants, mold release agents, dispersants, coupling agents and the like.
Whether or not the other components contributed to the development of the voids in the void-containing yarn is detected in components other than the polymer having crystallinity (for example, each component described later) in the void or at the interface portion of the void. It can be determined by whether or not. 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 said 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 antioxidants 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.). Agents and the like.
Further, the antioxidant can be used as a primary antioxidant and further combined with a secondary antioxidant. Examples of the secondary antioxidant include antioxidants commercially available under trade names such as Sumilizer TPL-R, Sumilizer TPM, Sumilizer TP-D (all manufactured by Sumitomo Chemical Co., Ltd.). It is done.

---- 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; Examples include petroleum waxes such as paraffin wax and polyethylene wax; and oil-based waxes such as castor oil or derivatives thereof and fatty acids or derivatives thereof.
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 retardant ---
There is no restriction | limiting in particular as said flame retardant, Although it can select suitably according to the objective, A brominated flame retardant is especially preferable. As the brominated flame retardant, 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 >>
The method for melting the resin composition is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a method for heating and melting the resin composition.
There is no restriction | limiting in particular as the temperature of the said heating, According to the kind etc. of resin in the said resin composition, it can select suitably. The molten resin composition becomes a high-temperature viscous liquid and is extruded from a nozzle. The molten resin composition is preferably devolatilized as necessary.

<< Spinning method >>
Spinning of the molten 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 molten resin composition is extruded through the nozzle, whereby the resin composition can be formed into a thread.
There is no restriction | limiting in particular as a shape of the hole of the said nozzle opening part, According to the objective, it can select suitably, For example, a circular shape, an atypical shape, etc. are mentioned. The variant means various variants that are not circular (perfect circles), for example, a gear, an ellipse, a petal, a multileaf, a star, a C, a Y, a cross, and a well. Etc.
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 of the nozzle opening, and thereby the cross section orthogonal to the drawing direction of the void-containing yarn. The shape of is also determined.

-Extrusion speed-
The void-containing yarn-producing 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.
The extrusion speed at the time of producing the undrawn yarn is not particularly limited and may be appropriately selected depending on the amount of the resin composition, the nozzle diameter, etc., but is usually about 2,000 m / min or less. Of extrusion speed (also called spinning speed).

-Cooling-
There is no restriction | limiting in particular as said cooling method, According to the objective, it can select suitably, For example, the method of passing with the water stored in the water tank etc., the method of cooling with cooling air, etc. are mentioned.
There is no restriction | limiting in particular as said cooling temperature (an air temperature, water temperature, etc.), Although it can select suitably according to the objective, 5 to 60 degreeC is preferable, 10 to 40 degreeC is more preferable, 15 to 35 ° C. is particularly preferred.
If the cooling temperature is less than 5 ° C., the crystallite size of the (010) plane contained in the void-containing yarn-producing yarn is too small, and the void-containing yarn-producing yarn is stretched as it is. In some cases, void-containing yarns cannot be produced. When the temperature exceeds 60 ° C., the crystallite size of the (010) plane becomes too large, and when used in the production of void-containing yarns, they may be cut during stretching.

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

  There is no particular limitation on the winding speed (also referred to as “winding speed”) of the void-containing yarn-producing yarn (hereinafter sometimes referred to as “undrawn yarn”), and it 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. If the winding speed is less than 5 m / min, the void-containing yarn manufacturing yarn may be uneven. If the winding speed exceeds 1,000 m / min, the void-containing yarn manufacturing yarn is cut by stress. Sometimes.

When the void-containing yarn is produced from the void-containing yarn-producing yarn, the yarn may be drawn immediately after the 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 the temperature and time of the said annealing, According to the objective, it can select suitably.

<Application>
The void-containing yarn manufacturing yarn has a metal-like gloss, high reflectivity, and high aesthetics because the crystallite size and crystallinity of the included crystal nucleus are suitable conditions for the production of void-containing yarn. Can be suitably used for the production of void-containing yarns having excellent properties and 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 drawing the void-containing yarn-producing yarn of the present invention. Here, the cavity means a vacuum domain or a gas phase domain existing in 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 the void-containing yarn when the shape of the hole in the nozzle opening is circular, and FIG. 1B is the cross-sectional view of the void-containing yarn when the shape of the hole in the nozzle opening is irregular. It is sectional drawing. As shown in FIGS. 1A and 1B, the void-containing yarn 43 has a cavity 60 inside the resin portion 61. The void-containing yarn may have a coating layer 12 as shown in FIGS. 2B and 3B.

<Cavity>
<< Aspect ratio >>
2A to 2C are diagrams for explaining an aspect ratio in a case where the void-containing yarn is circular, and FIG. 2A is a perspective view of the void-containing yarn, and FIG. 2B is a perspective view of FIG. FIG. 2C is a cross-sectional view of the void-containing yarn in FIG. 2A, and FIG. 2C is a cross-sectional view of the void-containing yarn in FIG.
3A to 3C are diagrams for explaining an aspect ratio when the void-containing yarn is atypical, and FIG. 3A is a perspective view of the void-containing yarn, and FIG. 3B is a view in FIG. FIG. 3C is a cross-sectional view taken along line AA ′ of the void-containing 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 defined as an average diameter r (μm) of the cavity 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 cavity (FIG. 2B). And the average length of the cavities 60 in the orientation direction (BB ′ cross section) of the cavities L (μm) (see FIG. 2C and FIG. 3B). L / r ratio in the case of 3C).

The aspect ratio can be calculated by the following method.
(1) The AA ′ cross section and the BB ′ cross section are each embedded in an epoxy resin, cut with a razor or a microtome, and examined with a scanning electron microscope. 62 (see FIGS. 2B and 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 orthogonal to the longitudinal stretching direction is m, and the longitudinal stretching direction N is the number of cavities included in the measurement frame 62 (see FIGS. 2C and 3C) having a cross section parallel to the horizontal axis.
(3) The maximum diameter (r _i ) of each cavity included in the AA ′ cross section is measured, the average diameter is r (see FIG. 2B and FIG. 3B), and the BB ′ cross section The length (L _i ) of each longest portion of the cavities included in the measurement frame 62 (see FIGS. 2C and 3C) 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. When the aspect ratio is less than 10, the reflectivity may be lowered, and when 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.

  In addition, the orientation direction of the cavity usually indicates a stretching direction. Usually, since longitudinal stretching is performed along the flow direction of the void-containing yarn-producing yarn during production, this longitudinal stretching direction 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). ), The average of these ratios (A / a) is preferably 0.05 or more and 0.4 or less.
Each cross-sectional area in the cross section can be measured by, for example, an image of an optical microscope or an electron microscope.

  The void-containing yarn preferably has a product of an average number P of cavities in the thickness direction and a refractive index difference ΔN between the resin part having a crystallinity and the cavities, 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 reflectance may decrease.

Here, the number of cavities in the thickness direction is a plane that includes a direction perpendicular to the surface 43a of the void-containing yarn 43 and perpendicular to the orientation direction of the cavities (AA in FIGS. 2A and 3A). In the 'cross section, that is, the cross section in the thickness direction ", it means the number of cavities 60 included in the thickness direction.
The average number P of cavities 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 The above is particularly preferable.
The number of cavities in the thickness direction can be measured by, for example, images of an optical microscope or an electron microscope. On these images, a plurality of straight lines are drawn in parallel in the thickness direction, The average number P can be obtained by calculating the average value of the number of cavities existing in.

Further, the resin part 61 having crystallinity refers to a part other than the cavity (part made of resin having crystallinity) in the void-containing yarn 43 (shaded part in FIGS. 1A and 1B).
Specifically, the difference in refractive index ΔN between the resin part having crystallinity and the cavity in the void-containing yarn is N1 when the refractive index of the resin part having N1 is N1 and the refractive index of the cavity is N2. It means a value of ΔN (= N1−N2) which is a difference from N2.
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 the cavity therein. is doing. That is, characteristics such as metallic luster, reflectivity, concealing property, heat insulating property, cushioning property, and the like can be adjusted by changing the mode of the void inside the void-containing yarn.

<Average diameter>
There is no restriction | limiting in particular as an average diameter of the said void containing thread | yarn, Although it can select suitably according to the objective, 5 micrometers-200 micrometers are preferable, 5 micrometers-100 micrometers are more preferable, and 5 micrometers-50 micrometers are especially preferable. When the average diameter of the void-containing yarn is less than 5 μm, it may be cut at the time of drawing, or a sufficient cavity may not be vacant, and a sufficient metallic luster and high reflectance may not be obtained. When it exceeds 200 μm, the ratio of the cavities is too large, the color becomes worse, and it becomes stiff, so that it may be inferior in texture when further processed and 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 within the 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 a 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-containing yarn is atypical. In this case, it means the length of the longest portion in the cross section in the direction orthogonal to the length direction of the void-containing yarn.
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.
There is no restriction | limiting in particular as said reflectance (%), Although it can select suitably according to the objective, 30% or more is preferable, 50% or more is more preferable, and 60% or more is especially preferable. 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 or an integrating sphere.

<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 is More preferred.
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 a density gradient tube method. When the density is less than 1.05 g / cm ^{3, 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 Examples thereof include polymers. Thereby, especially water resistance, hydrolysis resistance, tensile elastic modulus, bending resistance, etc. can be improved.
The coating layer may contain a dye. For example, by coating the 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. It is preferable in terms of spreading.
There is no restriction | limiting in particular as thickness of the said coating layer, According to the objective, it can select suitably, For example, 3-30% of the radius in the cross section (The said resin part and cavity part) of the said void containing thread | yarn Is preferred. When the thickness of the coating layer is less than 3% of the radius in the cross section of the void-containing yarn, mechanical characteristics may not be sufficiently imparted, and when the thickness exceeds 30% of the radius in the cross section of the void-containing yarn, The suppleness and feel as a fiber may be insufficient, and productivity may be reduced.

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

<< Drawing method >>
The method for drawing the void-containing yarn-producing yarn is not particularly limited and may be appropriately selected depending on the purpose. However, in any drawing method, the void-containing yarn-producing yarn is produced at the time of production. Stretching is preferably performed along the flowing direction, and it is more preferable to stretch the void-containing yarn-producing yarn so that necking appears.
Here, the 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 Course 6 Plastic Molding, edited by Polymer Society of Japan, published by Jinjin Shoin) (See the first edition issued on April 25, 1966). Moreover, the phenomenon that 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-producing yarn 5 is inserted into, for example, a heating furnace 30 adjusted to 25 ° C. to 150 ° C., and the tensile force is increased by applying 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 void is 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. By being exfoliated and stretched in such a way that an amorphous resin that has not progressed crystallization between the crystallites and other hard-to-stretch microcrystals is torn off at the interface with the microcrystalline phase or inside the amorphous phase. It is considered that this serves as a cavity formation source to form a cavity.
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 the 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 the 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 1,000 m / min is more preferable. When 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 uneven metallic luster. When the drawing speed exceeds 5,000 m / min, the yarn is likely 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. In addition, when the stretching speed is 5,000 m / min or less, the yarn is not easily broken and uniform stretching is easily performed. In particular, a large stretching apparatus for high-speed stretching is not required, and the cost is reduced. It is preferable in that it can be reduced.

-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. Moreover, it is preferable that the stretching temperature (° C.) is {glass transition temperature (Tg) −30} ° C. or higher in 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).

  The stretched void-containing yarn 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 the elapse of 5 seconds from the start of stretching, and excising the transparent to milky white portion by visual inspection with respect to the entire length. The 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 manufactured using the void-containing yarn-producing yarn of the present invention, it is uniformly stretched. Therefore, it has a metal-like gloss and high reflectivity and aesthetics. It is an excellent one. 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. Therefore, it is preferably used for various applications such as clothing, building materials, medical materials, electronic equipment members, and electric vehicle members. Can do.

  EXAMPLES The present invention will be specifically described below 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 the cross-section perpendicular to the resin extrusion direction when producing the void-containing yarn-producing yarn. The diameter was measured and the average value was calculated.

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

<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 above formula (I), (A) is a sample of void-containing yarn over 100 m after 5 seconds after neck stretching has started, and the entire length is transparent to milky white by visual inspection. The length (m) remaining after excising the part is shown. The yield is preferably 70% or more from the viewpoint of continuous productivity.

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

-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). 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 orthogonal to the longitudinal stretching direction is parallel to the longitudinal stretching direction. The number of cavities included in the cross-section measurement frame 62 (see FIG. 2C) is n.
Then, to measure the cross section of the measurement frame 62 perpendicular to the longitudinal stretching direction maximum diameter (r _i) of each one of the cavities included in (see FIG. 2B), 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 AL wires (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 Photoelectric 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 scored (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 2-6 and Comparative Examples 1-9)
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 producing the void-containing yarn-manufacturing yarns of Examples 2 to 6 and Comparative Examples 1 to 9 in the same manner as in Example 1, and in the same manner as in Example 1, each of the void-containing yarn-producing yarns. 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.

Moreover, in the production of the void-containing yarn of Example 1, Examples 2-6 and Comparative Examples described in Table 1 below were used using the yarns for producing the void-containing yarn produced in Examples 2-6 and Comparative Examples 1-9. Except having followed the conditions of 1-9, the void containing thread | yarn of Examples 2-6 and Comparative Examples 1-9 was manufactured by the method similar to Example 1, and the void containing was carried out by the method similar to 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.
In Comparative Examples 1 and 5, no metallic luster was observed, and in Comparative Examples 2 and 4, white turbidity was observed, but no metallic luster was observed. Comparative Examples 3 and 6-9 were Since it cut | disconnected, when the strand of these comparative examples 1-9 was used, the void containing thread | yarn which has metallic luster was not able to be obtained stably.

The production conditions for 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.
5 plots 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 shows a scatter diagram in which the relationship between the yield of the void-containing yarns of Examples 1 to 6 and Comparative Examples 1 to 9 and the crystallinity of the void-containing yarn-producing yarn is plotted.

From the results in Table 2 and FIGS. 5 to 7, the void-containing yarn can be stably and efficiently produced by stretching the void-containing yarn production yarn of Examples 1 to 6, and the void-containing yarn production yarn is obtained. It has been found that the void-containing yarn obtained by drawing has 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) 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 manufactured using the void-containing yarn-producing yarn of the present invention, it is uniformly stretched. Therefore, it has a metal-like gloss and high reflectivity and aesthetics. It is an excellent one. 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. Therefore, it is preferably used for various applications such as clothing, building materials, medical materials, electronic equipment members, and electric vehicle members. Can do.

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 (5)

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 to 5 nm in a (010) plane and having a crystallinity of 5 to 15%.   The yarn for producing a void-containing yarn according to claim 1, having an average diameter of 10 µm to 500 µm.   3. The void-containing yarn manufacturing yarn according to claim 1, comprising a crystalline polymer.   The element for producing void-containing yarn according to any one of claims 1 to 3, wherein the reflectance is 0.1% to 10%, and the reflectance of the void-containing yarn obtained by drawing 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.