JP2023094669A - Heat-shielding black filament, masterbatch for manufacturing heat-shielding black filament, and manufacturing method thereof - Google Patents

Abstract

To provide a heat-shielding black filament capable of realizing both excellent black color and heat-shielding property by incorporating a pigment other than carbon black into the filament, a masterbatch used for manufacturing the filament, a heat-shielding black yarn using the filament, and methods for manufacturing them.SOLUTION: There are provided: a heat shielding black filament that comprises a black pigment contained in an organic polymer in a dispersed state, in which the black pigment is a metal oxide or a metal composite oxide, and a thickness of the filament is 10 denier or less; a masterbatch for manufacturing the filament; a heat-shielding black yarn formed by converging the filaments; and methods for manufacturing them.SELECTED DRAWING: Figure 3

Description

The present invention relates to a heat-shielding black filament, and in particular, a heat-shielding black filament containing a black pigment other than carbon black pigment in a dispersed state, a masterbatch for producing the heat-shielding black filament, and , and methods for their production.

Generally, a carbon black pigment is widely used for black coloring, and the object to be colored is made black by containing the carbon black pigment.
However, carbon black pigments have the property of absorbing "infrared rays including near-infrared rays" contained in sunlight and the like. It makes me warm. That is, in general, a colored object made black by dispersing a carbon black pigment has poor heat shielding properties.

On the other hand, the colored object is a filament (long fiber, long fiber), a filament yarn (filament yarn) made by twisting it; a staple (short fiber, staple fiber), made by spinning it. Spun yarns (spun yarns, staple yarns); fabrics such as woven fabrics and non-woven fabrics made by processing them; In the case of such as, the original coloring object is thin, so it is difficult to disperse the coloring pigment and the dispersibility is poor. However, there is a problem that the fiber, which is the object to be colored, is cut in the middle.

Black pigments other than carbon black pigments generally have extremely poor dispersibility, and thus black pigments dispersed in fibers have been limited to carbon black pigments.
However, as described above, carbon black pigments absorb near-infrared rays and have poor heat shielding properties. Therefore, no black fiber, thread, or cloth in which a black pigment is dispersed has satisfactory heat shielding properties. In other words, there have been no fibers, yarns, or cloths in which a black pigment is dispersed to achieve both blackness (jet-blackness) and heat-shielding properties.

Therefore, in order to obtain a black fiber having excellent heat-shielding properties without problems, "dispersion of the black pigment inside the fiber" alone is insufficient (because it is difficult to disperse it inside the fiber). We had no choice but to use a method or rely on a combination of other methods.
As the other method, that is, as the already known "heat shielding fiber", for example, fine particles (titanium oxide, special ceramics, etc.) are kneaded, cross-sectional shape (cross-shaped, flat, constricted, etc.) , core-sheath structure, etc.), knitting methods (highly crimped, etc.), special ceramics fixed to the fibers, and fibers covered with a film that reflects near-infrared rays.

In Patent Document 1, there is a thermal control substance layer containing at least one substance selected from metal oxide fine particles and near-infrared absorbing dyes. (Complement of coefficient)” is described.
Titanium oxide, zinc oxide, tin oxide, zirconium oxide, indium oxide and the like are mentioned as the thermal control substance.
However, the invention of Patent Document 1 is an invention relating to a "layer", and does not describe or suggest a black heat-shielding pigment whose problem and purpose is that the fibers do not break even when dispersed in the fibers.

Patent Document 2 describes a waterproof sheet having an infrared reflective layer, and it is said that the solar reflectance in the near-infrared wavelength region can be increased to 30% or more by containing hollow ceramic balloons in the infrared reflective layer. there is
However, the invention of Patent Document 2 relates to a waterproof sheet, and in addition to the fact that the object is not a fiber, the heat shielding means is not based on pigment dispersion.

Patent Document 3 describes a core-sheath composite fiber in which an infrared absorbing agent is kneaded and the mass ratio of the core component and the sheath component is within a specific range. It also describes the use of hexaboride as the infrared absorber.
However, although the invention of Patent Document 3 relates to a fiber, it relates to a composite fiber consisting of a core and a sheath, and the cross-sectional shape of the fiber is complicated and costly.

Patent Document 4 describes a method for producing a heat-shielding polyester fiber in which a treatment liquid containing a vinyl chloride resin is applied to a polyester fiber containing inorganic compound particles, and the inorganic compound particles include titanium dioxide, potassium titanate, Lead titanate, lead oxide, zinc sulfide, zinc oxide, zirconium dioxide, silicon dioxide, alumina are mentioned.
However, the polyester fiber of the invention of Patent Document 4 has a flat cross-sectional shape and has 2 to 5 constricted portions, thereby realizing heat shielding properties.

Patent Document 5 describes a light-receiving heat-shielding film material containing fine particles of a conductive metal oxide and barium sulfate particles in a specific ratio, and examples of the conductive metal oxide include antimony-doped tin oxide. It is
However, the invention of Patent Document 5 is an invention relating to a "membrane", and was not aimed at preventing the fiber from being cut even when dispersed in the fiber.

Patent Document 6 describes a heat-shielding fiber fabric having a synthetic resin film formed on at least one side of the fiber fabric, and the synthetic resin film is said to contain metal particles and/or carbon black.
However, the invention of Patent Document 6 is also an invention relating to a "membrane", and was not aimed at preventing the fiber from being cut even when dispersed in the fiber.

As mentioned above, there are many technologies that make films and layers heat-shielding, but there are not many technologies that make the fibers themselves such as filaments and staples heat-shielding. It was not known about the "fiber that is difficult to cut in the middle due to its good dispersibility", which was also realized.
In addition, even if an attempt is made to obtain heat shielding properties by means other than dispersing black pigments, there is a limit to the range of colors, and there is no suitable method other than using carbon black as the black pigment. Otherwise, the good heat shielding effect has been lost.
That is, the compatibility of "excellent black color" and "excellent heat shielding properties" of the fiber has not been achieved in the fiber that does not depend on the "cross-sectional shape of the fiber" or the "composite structure of the fiber".

Japanese Patent Application Laid-Open No. 2003-251728 Japanese Patent Application Laid-Open No. 2004-360332 JP 2006-161248 A JP 2014-101612 A JP 2015-101930 A JP 2020-059952 A

The present invention has been made in view of the above background art, and the problem is that the filament itself contains a pigment other than "carbon black, which generally has poor heat shielding properties", so that both excellent blackness and heat shielding properties can be achieved. It is an object of the present invention to provide a heat-shielding black filament that can be manufactured, a masterbatch used for the production thereof, a heat-shielding black yarn using the masterbatch, and a method for producing them.

As a result of intensive studies to solve the above problems, the inventors of the present invention have found that, even with filaments of 10 denier or less, if a metal oxide or a metal composite oxide is used as a black pigment, carbon To complete the present invention by discovering that a black filament for heat shielding that satisfies both blackness and heat shielding property can be obtained without using black and having good dispersibility, without cutting the filament by coarse powder. reached.

Furthermore, in addition to the black pigment, if a color tone modifier such as an organic pigment is included (in combination), the blackness can be improved without impairing the heat shielding property, and the present invention has been completed. .

That is, the present invention provides a heat-shielding black filament in which a black pigment is contained in an organic polymer in a dispersed state,
The black pigment is a metal oxide or a metal composite oxide,
The present invention provides a black filament for heat shielding, characterized in that the filament has a thickness of 10 denier or less.

In the present invention, the black pigment includes zinc (Zn), chromium (Cr), titanium (Ti), manganese (Mn), antimony (Sb), iron (Fe), and bismuth (Bi). The present invention provides the heat shielding black filament, which is a metal composite oxide containing at least one metal element selected from.

The present invention also provides the aforementioned heat-shielding black filament having an average reflectance of 10% or more in the entire wavelength range of near-infrared light.

The present invention also provides a masterbatch for producing the heat-shielding black filament,
The masterbatch is characterized in that the black pigment is contained in the organic polymer in a dispersed state in an amount of 20% by mass or more and 80% by mass or less with respect to the entire masterbatch. .

The present invention also provides a black heat-insulating yarn obtained by twisting or bundling 5 or more and 50 or less of the black filaments for heat-insulating.

The present invention also provides a method for producing the masterbatch,
There is provided a method for producing a masterbatch, characterized by heating and melting the organic polymer, adding the black pigment to the inside of the melted organic polymer, and kneading the black pigment into a dispersed state. .

The present invention also provides a method for producing a heat-shielding black filament, which is characterized by using the above method for producing a masterbatch.

ADVANTAGE OF THE INVENTION According to this invention, the said problem and the said subject are solved, and even if carbon black is not used as a black pigment, the filament of the outstanding blackness (high jet-blackness) can be provided.
Furthermore, all carbonaceous materials (except diamond), including carbon black, absorb near-infrared rays and thus have the disadvantage of being inferior in heat-shielding properties. Since the near-infrared reflectance is high and the near-infrared rays are hardly absorbed, a heat-shielding black filament having excellent heat-shielding properties can be provided.
In the present invention, "near infrared rays" refers to light with a wavelength in the range of 780 nm to 2500 nm.

The present invention relates to fibers called filaments (long fibers). Since staples (short fibers) can be made by cutting filaments (long fibers) into short pieces, even if staples (short fibers) are manufactured and used, once the filaments (long fibers) are manufactured and used, It is included in the technical scope of the present invention.

If the object to be dispersed is a film or layer, even if the dispersibility of the black pigment is somewhat poor, there is a possibility that it can withstand use (acceptable). However, in the case of fibers such as filaments (long fibers), extremely good dispersibility is essential.
According to the present invention, metal oxides and composite oxides can be preferably dispersed (because they are dispersed) inside an organic polymer. Even if the fibers are as thin as denier or less, the fibers will not be split in the middle.
In addition, since the dispersibility can be improved (because the dispersibility is good), there is no decrease in physical properties such as mechanical strength of the fiber (to be dispersed) due to poor dispersibility.

Carbon black has better dispersibility than metal oxides and composite oxides. Therefore, it is suitable for fine materials such as fibers in terms of dispersibility, fiber strength, suppression of splitting, and the like. However, as described above, it absorbs near-infrared rays and is therefore inferior in heat shielding properties.
According to the present invention, it is possible to provide a heat-shielding black filament that achieves both "heat-shielding properties" and "suppression of splitting (fiber strength)".

When it comes to blackness, nothing beats carbon black. ADVANTAGE OF THE INVENTION According to this invention, even if it does not use carbon black, the black filament for thermal insulation which has excellent blackness (high jet-blackness) can be provided.
The "organic polymer fiber such as polyester fiber" of the present invention can have a heat shielding effect even though it is a black fiber without using carbon black.
That is, according to the present invention, it is possible to provide a heat-shielding black filament that achieves both "heat-shielding properties" and "blackness (jet-blackness)".

A "metal composite oxide" that reflects near-infrared light is known, and even if it is expected that a heat shielding effect can be obtained by using it, in the form of a filament, as described in Background Art, In other words, there has been almost no problem of obtaining a black heat-shielding material in the form of a yarn or a cloth made by knitting or weaving a yarn. In particular, filaments of 10 denier or less were even less so. It is possible that this is due to unconscious resignation due to the poor dispersibility of the "metal complex oxide".

According to the present invention, the black pigment can be dispersed in the interior of the organic polymer at a high concentration.
Specifically, for example, 5% by mass or more and 20% by mass or less of a black pigment can be included in the entire "black filaments for heat shielding obtained by dispersion".
As a result, both "heat shielding properties" and "blackness (jet-blackness)" are more preferably achieved.

Regarding filament production, dispersibility is secured (improved), high concentration gives versatility on the user side as a product, increases production efficiency, and according to the present invention, a high-concentration masterbatch is obtained, and the like, so masterbatching is preferred.
When using a "masterbatch in which a black pigment is dispersed inside an organic polymer" as a raw material for the heat-shielding black filament of the present invention, the black pigment is dispersed inside the organic polymer at a higher concentration and with good dispersibility. can be made

In the present invention, the black pigment is contained in the organic polymer in a dispersed state at 20% by mass or more and 80% by mass or less with respect to the entire "finally obtained masterbatch", so the masterbatch thus obtained is more preferable from the above points.
The "heat shielding black masterbatch of the present invention" for producing organic fibers (organic polymers) such as polyester fibers can impart a heat shielding effect to black fibers without using carbon black.
The present invention is also characterized in itself that it attempts to solve "the above-described problems that have never existed in the past or that have been thought to be absolutely impossible."

4 is a graph showing the spectral reflectance [%] of the black pigments used in Production Examples 1 and 2 in the visible light region and the near-infrared light region. Results of Evaluation Example 2, showing the spectral reflectance [%] of the black filament (thread) for heat shielding of the present invention and the carbon black-containing filament (thread) as a control in the visible light region and the near infrared light region. graph. The result of Evaluation Example 3, showing the temperature rise over time of the heat-shielding black filament (thread) of the present invention and the carbon black-containing filament (thread) as a control (heat-shielding property (result of heat storage test)). graph. It is a particle size distribution of black pigment A from which coarse powder was cut in Production Example 2. It is a particle size distribution of the black pigment B obtained by cutting the coarse powder in Production Example 7 and making the particle size smaller than that of the black pigment A. FIG. 10 is a diagram of near-infrared spectral reflectance (spectrum) of a sheet produced in Production Example 7 and evaluated in Evaluation Example 6; "CB" means carbon black. FIG. 10 is a diagram showing the heat shielding properties (results of a heat storage test) of the sheet produced in Production Example 7 and evaluated in Evaluation Example 6; FIG. 10 is a diagram showing near-infrared spectral reflectance (spectrum) of the sheet obtained in Production Example 8;

The present invention will be described below, but the present invention is not limited to the following specific embodiments, and can be arbitrarily modified within the technical scope.

[Black filament for heat shield]
The heat-shielding black filament of the present invention is a heat-shielding black filament in which a black pigment is contained in an organic polymer in a dispersed state, and the black pigment is a metal oxide or a metal composite oxide. and the thickness of the filament is 10 denier or less.

Hereinafter, the “black filament for heat shielding of the present invention” may be abbreviated simply as “the filament of the present invention”, and “metal oxide or metal composite oxide” may be simply referred to as “metal composite oxide It may be abbreviated as "things, etc."
In addition, "blackness (jet-blackness)" is defined as what is judged by visually evaluating the degree of blackness and color tone regardless of whether it is a filament, a thread, or a cloth. Filaments and yarns are defined as those that are tightly wound around a plate and visually observed from above the plate.

<Black pigment>
<<substance, composition, particle size>>
The black pigment in the present invention has a high reflectance in the near-infrared wavelength region and is not particularly limited as long as it is a "metal composite oxide or the like" that provides heat shielding properties to the organic polymer containing them, but zinc (Zn), chromium (Cr), titanium (Ti), manganese (Mn), antimony (Sb), iron (Fe), and at least one metal element selected from the group consisting of bismuth (Bi) "Metal composite oxides, etc." are preferable because they have high reflectance in the near-infrared wavelength region.
From the above points, it is particularly preferable to contain at least one metal element selected from the group consisting of zinc (Zn), chromium (Cr), manganese (Mn), iron (Fe), and bismuth (Bi). It is "composite oxides of metals, etc."

"Metal composite oxide, etc." is the above metal, the reflectance can be increased over the near-infrared wavelength range (entire range), so the heat shielding property can be improved, and the blackness can be adjusted (absorbance can be increased over the entire visible wavelength range. ) and dispersibility (pigment properties) can be improved.
Furthermore, it is particularly preferable that all the metals in the composite oxide are the above-mentioned metals for the above reasons.

The black pigment in the present invention may contain at least one metal element selected from the above group, and may contain one, two, or three or more metal elements. Preferably, it contains two or three metal oxides.
In addition, since it is acceptable as long as it is a "composite metal oxide or the like" containing one or more metals selected from the above group, oxides of other metals not belonging to the above group can be used as long as the above effects of the present invention can be achieved. is not excluded. Examples of the "other metals" include aluminum (Al), cobalt (Co), nickel (Ni), and the like.
In order to keep the content (upper limit) of the black pigment constant and increase the reflectance of near-infrared rays, although there is no limitation, it is preferable not to include the "other metals".

It is more preferable that both of the two or more metals in the composite oxide are the above-described metals (preferably the above-described particularly preferable metals) for the above reasons (above-mentioned reasons), and all the metals in the composite oxide are the above-described metals. (preferably the particularly preferred metals described above).
Specifically, although not limited, a composite oxide of manganese (Mn) and bismuth (Bi), a composite oxide of iron (Fe) and cobalt (Co), and the like are most preferable.

The particle size of "the black pigment before kneading with a kneader or the like with the heated and softened organic polymer", that is, the particle size of the "dry-mixed black pigment before kneading" used as a raw material is particularly limited. However, the number average particle diameter determined by the laser light scattering method is preferably 0.10 μm or more and 2.0 μm or less, more preferably 0.15 μm or more and 1.0 μm or less, and particularly 0.20 μm or more and 0.7 μm or less. preferable.
With a particle size within this range, a masterbatch and filaments with a suitable dispersed state can be produced. In addition, even with the same content, it is easy to increase the blackness, and the filament is difficult to break in the middle.

Coarse powder of black pigment (including aggregated ones) is preferably as small as possible. On the other hand, if the average particle size is too small or the particle size distribution is too sharp, during the production of the masterbatch, in a kneader such as a twin-screw extruder, In some cases, reaggregation tends to occur.
In order to suppress the re-agglomeration, it is preferable to optimize the shearing force by, for example, adjusting the rotation speed and peripheral speed of the screw of the twin-screw extruder.

<<reflectance of black pigment>>
The black pigment in the present invention preferably has an average reflectance in the near infrared region (780 nm to 2500 nm) of 30% or more, more preferably 36% or more, and particularly preferably 43% or more.
Moreover, the reflectance is preferably 6% or more, more preferably 8% or more, and particularly preferably 10% or more at any wavelength in the near infrared region (780 nm to 2500 nm).
In addition, at any wavelength of 1200 nm to 2500 nm in the near infrared region, the reflectance is preferably 20% or more, more preferably 30% or more, further preferably 40% or more, and particularly preferably 50% or more. 60% or more is most preferred.

The reflectance of the black pigment in the present invention at any wavelength in the visible light region (380 nm to 780 nm) is preferably 10% or less, more preferably 7% or less, further preferably 4% or less, and particularly preferably 3% or less. .
If it is below the said upper limit, blackness (jet-blackness) will increase. In addition, it becomes pure black with no particular tint.
The above "near-infrared and visible reflectance of black pigment" is defined as a spectrophotometer measurement of a sheet or film in which the pigment is uniformly dispersed in a resin vehicle.

<Color tone modifier>
When the filaments or the filaments are bundled into a thread, the sensory (by visual observation) blackness tends to be inferior. That is, when the semi-drawn yarn (POY) is re-drawn to form a drawn yarn (FDY), which is wound around a plate or the like and visually observed, the blackness tends to be poor. In addition, when trying to achieve a high blackness with only a black pigment, it is necessary to increase the concentration of the black pigment (for example, 50% by mass), which causes an event in which the filament or thread is cut in the middle. Sometimes.
Therefore, it is conceivable to cut the coarse powder of the black pigment and further reduce the particle size, but this may change the color of the black color. Increasing the blackness in the form of filaments and threads, that is, increasing the blackness and adjusting the color (eliminate coloration), for example, reduces the glossiness of the thread surface, so it can be used as a film (membrane) or clumps. It is far more difficult than increasing the blackness in the (structure) state.

In order to improve such phenomena or further improve blackness, it is preferable to incorporate a color tone adjusting agent. If the blackness is further improved, the applications will be further expanded.
In addition to the black pigment, the heat-shielding black filament of the present invention preferably further contains a color tone adjusting agent inside the organic polymer. The color tone adjusting agent may be used alone or in combination of two or more.
The color tone adjusting agent is contained for the purpose of further enhancing blackness and further adjusting the color tone even in black.

In addition, when trying to achieve the desired blackness (color tone) only with metal oxides or their composite oxides, the content must be increased, which may reduce the strength of the filament or thread. However, even in such a case, if a color tone adjusting agent is used in combination, it is possible to improve the blackness (jet-blackness) while suppressing the decrease in filament or thread strength.
Even if the color tone modifier used in combination absorbs near-infrared light, the total solar reflectance (TSR) does not decrease significantly, so that the combined use of the color tone modifier does not reduce the heat shielding properties. not seen (see Examples).

As the color tone adjusting agent, a substance having a complementary color tone (in the visible light wavelength region) to the black pigment, that is, the composite metal oxide or the like, is preferable because the above object can be achieved.

Specifically, the color tone modifier is preferably an "organic or inorganic""dye or pigment" other than "a carbonaceous material such as carbon black" or "the above-described composite metal oxide, etc." and having the above physical properties. , “organic pigments or inorganic pigments” are more preferred, and organic pigments are particularly preferred.
Pigments do not deposit on the filament surface. Further, since there are many kinds of organic pigments, it is easy to adjust the color tone.

The organic pigment may be any one of blue, yellow, green-red, etc. having sharp absorption at a specific wavelength. Also, having (broad) absorption at wavelengths in the visible region; having absorption other than red (R), green (G) or blue (B); or the like may be used.

Specifically, there is no particular limitation, but from the viewpoint of dispersibility in general-purpose filament materials such as PET, and from the viewpoint of increasing blackness without reducing heat shielding properties, etc., it is listed in Table 7 below. Organic pigments are preferred.
In addition, the following organic pigments are preferred. Pigment number, color index (C.I. number), CAS. NO. indicates
P. BL-15:3 (copper phthalocyanine blue beta type) (74160) (CAS.NO 147-14-8),
P. B-60 (69800) (CAS.NO 81-77-6),
P. G-7 (74260) (CAS.NO 1328-53-6),
P. Y-95 (20034) (CAS.NO 5280-80-8),
P. Y-147 (60645) (CAS.NO 4118-16-5),
P. R-149 (CAS.NO 4948-15-6),
Aniline black, perylene black and the like are also preferred.

Among them, P. Y-147, P.I. R-149, P.R. BL-15:3 and the like are particularly preferable from the above points, the fact that they have a track record of use in fibers, and the fact that they are less likely to break.

By using a color tone adjusting agent, especially an organic pigment, even if it is simply called "black", it is possible to adapt to the preferences, demands, and performance differences in terms of blackness and tint depending on the application.
In addition, it is easier to achieve an increase in the degree of blackness by visual observation than with a black pigment alone. That is, even if the content of the black pigment is reduced, the deterioration of the blackness can be compensated for.

When carbon black (CB) is blended to adjust the color tone or improve the blackness, the reflectance of near-infrared light is reduced, so the total solar reflectance (TSR) is reduced and the heat shielding property is improved. However, for example, as shown in Production Example 8 and Evaluation Example 7, when an organic pigment is used as a color tone modifier, the total solar reflectance (TSR) decreases by only about 2% at most, and the combined use Surprisingly, the heat shielding property did not deteriorate.

When the color tone modifier is used, the amount of the color tone modifier used (the amount dispersed in the organic polymer) is not particularly limited, but is 0.2% with respect to the black pigment, that is, the composite metal oxide and the like as a whole. It is preferably from 1% by mass to 45% by mass, more preferably from 1% by mass to 40% by mass, still more preferably from 2% by mass to 35% by mass, and particularly preferably from 4% by mass to 30% by mass.
Too much color tone modifiers such as organic pigments may absorb near-infrared rays, resulting in poor heat shielding, reduced filament strength, increased material and manufacturing costs, and decreased processability of the masterbatch. , the dispersibility of the black pigment may decrease.

<Organic polymer>
The heat-shielding black filament of the present invention comprises the black pigment contained in an organic polymer in a dispersed state.
The organic polymers include all known organic polymers for synthetic fibers. The synthetic fibers also include semi-synthetic fibers derived from natural products.

Although not particularly limited, specifically, for example, polyester; nylon, nylon 6, nylon 66, aromatic nylon, polyamide such as aramid; acrylic polymer such as poly (meth) acrylate (copolymer); polystyrene ( (co)polymers such as vinyl acetate and vinyl alcohol; vinyl polymers such as vinylon; chlorine polymers such as polyvinylidene chloride and polyvinyl chloride;

Although not limited, polyester is particularly preferable for obtaining the above effects of the present invention. Examples of the diol component of the polyester include ethylene glycol, propylene glycol, 1,3-propanediol, butylene glycol, butanediol, their "di-form" or "tri-form", 1,4-cyclohexanedimethanol and the like, and examples of the dicarboxylic acid component of the polyester include terephthalic acid, 2,6-naphthalenedicarboxylic acid and the like. mentioned.

<include in distributed state>
It is essential that the heat-shielding black filament contains the black pigment described above in a dispersed state inside the organic polymer. Since it is "inside the organic polymer", it excludes an aspect in which there are a specific number of pigment particles protruding from the surface of the organic polymer, that is, from the surface of the filament. Such aspects include cases where the strength of the filament or thread is inferior, cases where the surface becomes dirty when rubbed, cases where the heat shielding effect is low, and the like.
Moreover, an embodiment in which a black pigment is applied to the surface of the filament after production, that is, an embodiment in which the surface of the filament is covered with a "composition containing a large amount of black pigment" is also excluded.
In such a mode, the manufacturing cost increases, the surface becomes dirty when rubbed, and the heat-shielding effect deteriorates due to peeling of the applied material.

The volume-average particle size of the black pigment contained inside the heat-shielding black filament of the present invention is preferably 0.10 μm or more and 2.0 μm or less, and preferably 0.15 μm, although it depends on the diameter of the filament to be obtained. 1.0 μm or less is more preferable, and 0.20 μm or more and 0.7 μm or less is particularly preferable.
If the particle size is too small, it may become difficult to disperse.

According to the present invention, even in the case of fine dispersion objects (specifically, organic polymers) such as filaments and fibers, metal complex oxides and the like can be dispersed surprisingly well inside the organic polymer. The present inventors have discovered that both filament cut suppression/dispersibility and heat shielding properties can be achieved.
The present invention has also been made based on the discovery that blackness and heat shielding properties can be achieved at the same time without making the cross section of the fiber into a special shape or making the fiber into a covering structure or a core-sheath structure. .
A method for including the black pigment in the organic polymer in a dispersed state will be described later.

The particle size distribution, the amount of coarse powder, etc. of the black pigment contained in the filaments are the same as those of the black pigment described in <Method for producing masterbatch> described later.

<Black pigment content>
In the heat-shielding black filament of the present invention, the black pigment is preferably contained in the organic polymer in an amount of 30% by mass or less with respect to the entire heat-shielding black filament. More preferably 5% by mass or more and 20% by mass or less, more preferably 4% by mass or more and 15% by mass or less, and particularly preferably 3% by mass or more and 10% by mass or less.

If the content of the black pigment is too high, the black pigment cannot be dispersed, the mechanical strength of the filament is lowered, the preparation of the filament is difficult, the filament is difficult to make into a yarn, and the staple yarn is difficult to spin. In some cases, it may be difficult to weave the obtained threads (yarns) into a cloth, or it may be difficult to produce a non-woven fabric from the obtained threads (yarns).
On the other hand, if the content of the black pigment is too small, the blackness (jet-blackness) is poor, or the near-infrared rays cannot be sufficiently reflected and the heat-shielding property is poor. There are cases, etc.

<Shape such as filament thickness>
It is essential that the filament of the present invention have a thickness of 10 denier or less. In the case of thick "fibers such as filaments" and in the case of membranes, layers or masses, poor dispersibility is often not a problem. In addition, blackness can be easily increased in many cases.
In the present invention, even if the fineness is 10 denier or less, the "metal composite oxide, etc.", which is generally inferior in dispersibility to carbon black, is well dispersed, and the "metal composite oxide, etc." Fibers such as filaments will not be cut.

The upper limit of the thickness of the filament of the present invention is essentially 10 denier (85 μm) or less, preferably 6 denier (51 μm) or less, more preferably 4 denier (34 μm) or less, and particularly 2 denier (17 μm) or less. preferable.
If the filament is too thick, it may be difficult to spin the filament into yarn, and even if the filament is cut into short pieces and stapled, it may be difficult to spin. In addition, if it is too thick, even if the dispersed particle size of the black pigment is large (even if it is aggregated), it is difficult to cause a problem, and the effect of the present invention due to good dispersibility may not be obtained. .

Although the lower limit of the thickness of the filament of the present invention is not particularly limited, it is preferably 1 denier (10 μm) or more, and particularly preferably 2 denier (15 μm) or more.
If it is too thin, it may be difficult to manufacture, it may be easy to cut, the diameter of the black pigment coarse powder cannot be ignored with respect to the filament diameter, and it may be difficult to reel or spin.

The shape of the cross section of the filament of the present invention is not particularly limited, but it can be a normal perfect circle or ellipse without special measures such as having a depression, a star shape, or a core-sheath structure. also provides excellent heat insulation. Compared to the case where the cross section of the filament, that is, the cross section of the organic polymer has a special shape, the manufacturing cost of the filament can be reduced.

The filaments (long fibers) of the present invention can be cut into staples (short fibers), in which case the length of the staples (short fibers) is not particularly limited and can be any length. (can be cut). Spunbond and meltblown processes for nonwoven fabrics are also possible.

<Average reflectance of heat-shielding black filament>
The filament of the present invention can have an average reflectance in the near infrared region (780 nm to 2500 nm) of 10% or more, 15% or more, or 20% or more, It can be 25% or more, it can be 30% or more. Therefore, the filament of the present invention preferably has an average reflectance in the near-infrared region (780 nm to 2500 nm) of 10% or more, more preferably 15% or more, even more preferably 20% or more, and particularly preferably 25% or more. 30% or more is most preferred.

Further, the reflectance at any wavelength from 1200 nm to 2500 nm in the near infrared region is preferably 30% or more, more preferably 35% or more, and particularly preferably 40% or more.

The reflectance of the filament of the present invention at any wavelength in the visible light region (380 nm to 780 nm) is preferably 30% or less, more preferably 25% or less, still more preferably 20% or less, and particularly preferably 15% or less.
If it is less than the above upper limit, the blackness (jet-blackness) is high, and a pure blackness (jet-blackness) is obtained without being particularly tinted.
The above "near-infrared and visible reflectance of the heat-shielding black filament" is measured according to JIS L1013:2010 by the method described in Examples, and is defined as that measured.

<Masterbatch>
The present invention is a masterbatch for producing the heat shielding black filament of the present invention, wherein the black pigment is contained in the organic polymer in an amount of 20% by mass or more and 80% by mass or less with respect to the entire masterbatch. It is also a masterbatch characterized by being contained in a dispersed state.

In the production of black filaments for heat shielding, it is preferable to prepare a masterbatch having a high concentration of black pigment or the like in order to have versatility. That is, it is also preferable to transfer or sell the masterbatch as a product with a high black pigment concentration.
The person who obtains the masterbatch dilutes it with an organic polymer to prepare a composition for making filaments.

According to the present invention, in the masterbatch, even if the concentration of the black pigment in the organic polymer is high, the dispersibility is good (because the dispersibility can be improved). Even when a filament is produced, the dispersibility is maintained even within the filament, and a mechanically strong filament can be obtained without being cut in the middle of the filament.

In the masterbatch of the present invention, the black pigment is preferably contained in the organic polymer in a dispersed state in an amount of 20% by mass or more, more preferably 30% by mass or more, and particularly preferably 40% by mass with respect to the entire masterbatch. It is desirable that at least 10% by mass is contained in a dispersed state.
If it is more than the said lower limit, the versatility and application range as a masterbatch will expand, it will become easy to use, and it will become easy to show a meaning, an effect, and a merit as a masterbatch. On the other hand, if it is not more than the above upper limit, the dispersibility (stability) of the black pigment is obtained, and preparation of the masterbatch is facilitated.

<Black thread for thermal insulation>
The present invention also provides a heat-insulating black filament comprising 5 or more and 50 or less heat-insulating black filaments of the present invention, which are bundled, twisted, or bundled together. The present invention is also a filament yarn (filament yarn) formed by twisting or bundling filaments (long fibers, long fibers).
The number is preferably 5 or more and 50 or less, more preferably 10 or more and 40 or less, and particularly preferably 15 or more and 30 or less.
Within the above range, there are effects such as easy preparation of filament yarn, easy improvement of blackness and heat shielding properties, favorable strength, widening of applications, and easy weaving into cloth.

The filament yarn (black yarn for heat shielding) obtained from the filament of the present invention and the cloth obtained from it have a black luster, have a smooth texture, and preferably reflect near infrared rays and have heat shielding properties. is high.

The filaments (long fibers, long fibers) of the present invention are cut into short staples (short fibers, staple fibers), which are spun to form spun yarns (spun yarns, staple yarns), which are heat-shielding black yarns. can do.
The heat-insulating black yarn, which is a spun yarn, can be woven into a raised cloth or a non-woven fabric. By using the present invention, it is possible to suitably obtain a cloth with a raised finish, a nonwoven fabric (spunbond), or the like, which has a high heat shielding property.

[Production method]
<Manufacturing method of masterbatch>
<<Black pigment and organic polymer when feeding extruder (kneader)>>
In order to prepare a masterbatch having a high black pigment concentration and to prevent the filament or thread from being cut in the middle, it is preferable to cut the coarse powder from the black pigment.
It is preferable to cut coarse powder of 2.0 μm or more, more preferably cut coarse powder of 1.5 μm or more, and particularly preferably cut coarse powder of 1.0 μm or more.

In order to obtain the above effects, etc., the number average particle diameter of the black pigment (in the kneader) used in the production of the masterbatch is preferably 0.2 μm or more and 1.0 μm or less, more preferably 0.3 μm or more, as a median diameter (D50). 0.8 μm or less is more preferable, and 0.4 μm or more and 0.5 μm or less is particularly preferable.

In addition, the organic polymer used in masterbatch production can be pulverized in advance into powder, and then put into an extruder (kneader) together with a black pigment or the like to improve dispersibility, and Preferred to avoid disconnection.
Furthermore, it is particularly preferable to put a mixture of pulverized powdery organic polymer and pelletized organic polymer into an extruder (kneader) together with a black pigment or the like.

<<Kneading conditions>>
The present invention is a method for producing "the above-described masterbatch", wherein the organic polymer is heated and melted, and the black pigment is contained in the melted organic polymer and kneaded to form a dispersed state. It is also a method for producing a masterbatch characterized by

Apparatus used for kneading includes a twin-screw extruder (twin-screw kneader, kneader), three rolls, a planetary mixer, a Banbury mixer, and the like.
Among them, a twin-screw extruder is preferable because it has high black pigment dispersibility, fine adjustment of the temperature (change, gradient) during kneading, continuous kneading, stable dispersion and no variation, etc. .

The temperature during kneading depends on the softening point of the organic polymer used, but is preferably 150 to 280°C, more preferably 165 to 270°C, and particularly preferably 180 to 260°C.

When a twin-screw extruder with a screw diameter of 28 mm is used, the screw rotation speed is preferably 200 to 1200 rpm, more preferably 300 to 1000 rpm, and particularly preferably 500 to 750 rpm.
When a twin-screw extruder with a screw diameter other than 28 mm is used, it is desirable that the peripheral speed (mm/s) falls within the above (more particularly) preferable range.

If the coarse powder of the black pigment is cut and the particle size distribution is sharp, the filaments in which the black pigment is dispersed and included will not be cut at the location of the coarse powder. Re-agglomeration of the black pigment may occur easily in the smelting machine.
In order to suppress the reaggregation, the rotational speed and the peripheral speed are adjusted to optimize the shearing force applied to the black pigment in the organic polymer.

In the method for producing a masterbatch of the present invention, the organic polymer is pulverized to a volume average diameter of 1000 μm or less, put into a kneader, and kneaded with the black pigment. Preferred for dispersion in polymers.
Pulverization to a volume average diameter of 700 µm or less is more preferable, and 500 µm or less is particularly preferable.

The organic polymer that is dry ground to the above volume average diameter may be part or all of the organic polymer used.
Hereinafter, the material obtained by pulverization to the above volume average diameter is referred to as "powder organic polymer", and the material before pulverization is referred to as "pellet organic polymer".
Although not particularly limited, the "powdered organic polymer" is preferably 20 to 100% by mass, more preferably 25 to 75% by mass, and particularly preferably 30 to 50% by mass, based on the total organic polymer.

First, a powdered organic polymer and a black pigment are dry-mixed and uniformly mixed, and then a pellet-shaped organic polymer is added, further dry-mixed, uniformly mixed, and then charged into a kneader. By doing so, a masterbatch is obtained in which the black pigment is suitably dispersed in the organic polymer.
By using the masterbatch to produce filaments, heat-shielding black filaments in which the black pigment is contained in the organic polymer in an excellent dispersed state can be obtained.

<<Formulation of dispersing aid>>
In the method for producing the masterbatch of the present invention, it is preferable to mix and knead a long-chain fatty acid amide as a dispersing aid.
The long-chain fatty acid amide may be blended at any stage of the above-described "dry mixing of the organic polymer and the black pigment". It is preferable because it is easy to obtain an effect on the dispersibility of the pigment.

The long-chain fatty acid of the long-chain fatty acid amide is preferably a fatty acid having 8 to 24 carbon atoms, more preferably a fatty acid having 12 to 22 carbon atoms, and particularly preferably a fatty acid having 16 to 20 carbon atoms. Although the presence or absence of a double bond is acceptable, a saturated fatty acid is preferred.
The long-chain fatty acid amide may be monovalent or divalent, but is preferably divalent, and alkylenebiscarboxylic acid amide is particularly preferred because it tends to have a good effect on the dispersibility of the black pigment in the masterbatch.
Among them, the alkylene group is preferably an ethylene group, a propylene group, or the like.
The above dispersing aids can be used singly or in combination of two or more.

When metal salts of long-chain fatty acids such as zinc stearate and calcium stearate are used as dispersing aids, organic polymers (especially polyesters) may decompose.

<<Formulation of color tone adjusting agent>>
In the method for producing the masterbatch of the present invention, it is also preferable to further mix and knead the aforementioned “color tone modifier such as an organic pigment”.
When blending the color tone modifier, it may be blended at any stage of the above-described "dry mixing of the organic polymer and the black pigment". It is preferable because the dispersibility of the color tone adjusting agent therein is improved.

That is, it is particularly preferable that the following steps (1) to (5) are performed as the method for producing the masterbatch of the present invention. A manufacturing method in which some of the following steps (1) to (5), for example two or less, are not performed is also preferred.
Through such a process, a black pigment having a high reflectance in the near-infrared region can be included in fine fibers in a suitable dispersed state.

(1) The black pigment is coarsely cut before it is put into the kneader.
(2) At least part of the organic polymer is dry pulverized to reduce the volume average diameter before being charged into the kneader, and then mixed with the black pigment, or mixed and then mixed with the total amount of the organic polymer. do.
(3) A black pigment, which is a metal oxide or a metal composite oxide, and an organic polymer are heated and kneaded in a kneader such as a twin-screw extruder to produce a masterbatch.
(4) Perform heat kneading with a specific dispersing aid.
(5) When using a twin-screw extruder, adjust the screw rotation speed (shear force) to an optimum value.

<< Effect of manufacturing method >>
In the present invention, the black pigment can be included in the filament at a high concentration due to its excellent dispersibility, the blackness and heat shielding properties are increased, and the filament is prevented from being broken due to coarse powder or aggregates of the black pigment.
In the present invention, if the filament has a diameter within the above range (even if it is) without devising such as coating the periphery of the fiber with a heat-shielding pigment or making the fiber cross-sectional shape special, Surprisingly, it was found that the "specific black pigment other than carbon black" can be included in fine fibers while maintaining a suitable dispersed state, preferably by the above-mentioned kneading method and preferably by the above-mentioned dispersing aid. is.

<Method for producing black filament for heat shielding>
The present invention also provides a method for producing a heat-shielding black filament, characterized by using the method for producing a masterbatch described above.
The filament manufacturing method is not particularly limited, and known methods can be used.

The present invention also provides a method for producing a black heat-insulating filament, comprising converging, more specifically, twisting or bundling 5 or more and 50 or less of the above-mentioned heat-insulating black filaments.

<Application>
Black filament for thermal insulation of the present invention; staple obtained therefrom (short fiber, staple fiber); filament yarn obtained by spinning it (filament yarn), spun yarn obtained by spinning it (spun yarn, staple yarn), etc. Heat-insulating black yarn; woven fabrics, non-woven fabrics, knitted fabrics, and other fabrics obtained therefrom are used in all applications requiring heat-shielding properties.
Application to (the surface material of) a structure that is exposed to direct sunlight but whose temperature should not be raised (the structure itself, its cover, attachment to it, etc.) is particularly effective.

Specific examples include, but are not limited to, interior materials for automobiles, trains, airplanes, ships, etc.; building materials and interior materials for houses, buildings, towers, stadiums, etc.; outdoor items such as roads, pillars, signboards; belongings such as bags and equipment covers; daily necessities and household items such as curtains, carpets and chairs; clothing such as T-shirts, suits, skirts and hats;

The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples and Production Examples unless it exceeds the gist of the invention.

Production example 1
<Production of masterbatch used for production of black filament for heat shielding>
<<Using black pigment that has not been cut into coarse powder>>
As a black pigment, 2500 g of "composite oxide of iron (Fe) and chromium (Cr) (Chromium Iron Oxide)" exhibiting the spectral reflectance shown in FIG. 02 bottle grade polyethylene terephthalate (hereinafter abbreviated as "PET") and 25 g of ethylene bisstearic acid amide as a dispersing aid were mixed under the following conditions using a twin-screw extruder capable of rotating at high speed. It was kneaded to produce a “masterbatch of 50% by mass of black pigment” for producing a black filament for heat shielding.

The black pigment used had a number average particle size of 0.7 μm as determined by a laser light scattering method. Although the particle size distribution was broad, it was used as it was without cutting the coarse powder.

As the PET, 1500 g of "pellet-shaped PET" having a size of about 7 mm, and the pellet-shaped PET were dry pulverized using a turbo disk mill to obtain a volume average diameter of 500 µm (particle size distribution of 400 to 1000 µm). 1000 g of powdered PET" was mixed, and a total of 2500 g was used.
That is, pellet-like PET and powder-like PET were used at a ratio of 3:2 (mass ratio) with respect to the entire masterbatch.

First, 1000 g of the "powder PET" obtained above, 2500 g of the black pigment, and 25 g of the ethylenebisstearic acid amide were dry-mixed using a general-purpose mixer.
After complete mixing, 1500 g of the above "pelletized PET" was added and dry-mixed using the same mixer for complete mixing.

Each mass of the used black pigment, organic polymer and dispersion aid is shown in Table 1 below together with each mass in "Production Example 2 using a black pigment from which coarse particles have been cut" described later (collectively). .

The obtained mixed powder was kneaded using a twin-screw extruder capable of rotating at high speed under the following configuration and conditions to produce a masterbatch.
The rotation speed (peripheral speed) of the screw was swung to the following four points for kneading.

Production example 2
<Production of masterbatch used for production of black filament for heat shielding>
<<Using black pigment with coarse powder cut>>
The black pigment used in Production Example 1 had a number average particle size of 0.7 μm and a broad particle size distribution.
Therefore, the black pigment "composite oxide of iron oxide and chromium oxide" used in Production Example 1 was cut off from coarse particles using a vortex flow (forced vortex type) airflow classification chamber rotating classifier.

Although the number average particle diameter of the black pigment from which coarse particles were cut remained at 0.7 μm, the particle size distribution became sharper than the black pigment (without coarse particles cut) used in Production Example 1, especially , coarse powder of 1.5 μm or more was largely cut.
FIG. 4 shows the particle size distribution of the black pigment cut into coarse particles. The median diameter (D50) of the black pigment cut into coarse particles was 0.750 μm.
Hereinafter, the black pigment from which coarse powder has been cut as described above may be abbreviated as "black pigment A".

A masterbatch was produced in the same manner as in Production Example 1 using the black pigment from which coarse particles were cut as described above, and the dispersibility of the black pigment in the masterbatch was quantitatively evaluated as follows.
The results are shown in Table 3 below together with the results of Production Example 1.

Evaluation example 1
<Evaluation of masterbatch (manufacturing method)>
<<Evaluation of dry mixing before kneading>>
First, the powdered PET, black pigment, and dispersing aid were dry-mixed to eliminate segregation (mixing unevenness). Sometimes there was complete mixing. That is, there was no segregation and no mixing unevenness.
Therefore, the black pigment was uniformly dispersed without segregation in the masterbatch obtained by kneading with an extruder.
The number of revolutions (peripheral speed) of the screw was set at 4 points, but all of them were uniform with no segregation and excellent as a masterbatch for manufacturing filaments.

<<Evaluation of dispersibility of black pigment in masterbatch>>
The dispersibility of the black pigment in the masterbatches obtained in Production Examples 1 and 2 was evaluated by performing a filtration pressure increase test using a filter tester manufactured by LabTech. All filter mesh sizes were 10 μm.
The results are shown in Table 3 below. The smaller the filtration pressure rise [MPa], the better the dispersibility.

Pigment dispersibility is generally proportional to the shear force (screw rotation speed), but it does not monotonically increase with the shear force (screw rotation speed) (high-speed screw rotation is not necessarily a good result). , it was found that there is an optimum value for the shear force (screw rotation speed). It is considered that the black pigment, which had once been dispersed, caused secondary aggregation again when excessively high-speed stirring was applied.

The black pigment of Production Example 1, which was not subjected to coarse powder cutting, had the best dispersibility at 750 rpm, and worsened at higher rotation speeds.
The black pigment of Production Example 2, from which coarse particles were cut, had the best dispersibility at 500 rpm, and worsened at higher rotation speeds. The black pigment in Production Example 2, from which coarse particles have been cut, has a uniform particle size distribution (sharp) due to the removal of coarse particles.

Production example 3
<Production of filaments>
For the general black pigment of Production Example 1 (without coarse powder cut), a masterbatch obtained at a screw rotation speed of 750 rpm is used, and for the black pigment A of Production Example 2 (with coarse powder cut), the screw rotation speed Using the masterbatch obtained at 500 rpm, filaments (yarns) were produced below and spinning tests were carried out.

Using the masterbatches obtained in Production Examples 1 and 2, three types of samples (1), (2), and (3) shown below were produced as multifilaments (filament yarns) having a thickness of 2 denier.
Filament (fiber) production was performed on a melt extrusion spinning tester.
That is, as a masterbatch and an organic polymer that is a natural resin, the pellet-shaped PET used in the production of the masterbatch is put into a melt extrusion spinning tester, heated and softened, and extruded from a spinning die to produce a semi-stretched yarn. Obtained.
The filament yarn was made by collecting (twisting or bundling) 36 filaments (long fibers) into a yarn of 75D36F.

(1) 3.0 parts by mass of black pigment (6.0 parts by mass in masterbatch) and masterbatch production using a masterbatch produced using "black pigment that has not been coarsely cut" in Production Example 1 A filament yarn was spun from 94 parts by mass of the same organic polymer (PET) as that used in the above.
(2) 6.0 parts by mass of black pigment (12.0 parts by mass in masterbatch) and masterbatch production using the masterbatch produced using "black pigment that has not been cut into coarse powder" in Production Example 1 A filament yarn was spun from 88 parts by mass of the same organic polymer (PET) as that used in the above.
(3) Using a masterbatch produced using the "black pigment with coarse powder cut" (black pigment A) in Production Example 2, black pigment (black pigment A) 10.0 parts by mass (20.0 parts by mass in the masterbatch parts) and 80 parts by mass of the same organic polymer (PET) as that used in the masterbatch production.

Evaluation example 2
<Evaluation of filament yarn>
<<Visual evaluation of the presence or absence of cutting (thread breakage) and blackness>>
In sample (1), there was no filament breakage (thread breakage) and the color was "light gray". It was almost black and could be used depending on the application, but the blackness was low (see Table 4).
Sample (2) had no filament breaks (thread breaks) and was "light gray to black" in color. Although it was black and could be used depending on the application, the blackness was slightly low (see Table 4).

In sample (3), there was no filament breakage (thread breakage), the color was "black", and the blackness was high (see Table 4).
In sample (3), as described above, the black pigment content was increased. Since the blending amount was increased, we were concerned about yarn breakage during spinning, so we used the masterbatch produced using the “black pigment from which coarse powder was cut” in Production Example 2.
10.0 parts by mass of black pigment (20.0 parts by mass in the masterbatch) and 80 parts by mass of PET, despite the large amount of black pigment, there was no problem of yarn breakage, and fibers that looked black to the naked eye were obtained. .

Even if the black pigment A, which had been cut into coarse particles, was contained in a large amount in the filament, the yarn breakage was less likely to occur.

Table 4 shows the mixing ratio of the black pigment (composite oxide of iron and chromium) and the organic polymer (PET) and the evaluation results in the spinning.
The numbers in Table 4 indicate parts by weight of the formulation. The numbers in parentheses indicate parts by weight of the 50% by mass masterbatch formulation. The same applies to FIGS. 2 and 3 as well.

In Table 4, those without "*" in the mass parts in parentheses (Samples (1) and (2)) use the masterbatch manufactured using "black pigment that has not been coarsely cut" in Production Example 1. The one with "*" in the mass part in parentheses (sample (3)) is a masterbatch produced using "coarse powder cut black pigment" (black pigment A) in Production Example 2. It is used.

In a masterbatch that was not produced by a method such as Production Examples 1 and 2, the dispersibility of the black pigment was poor, and when it was made into a filament (thread), the black pigment that was not well dispersed or coarse powder was included. Thread breakage was likely to occur at points where the black pigment was present.
"Methods like Production Examples 1 and 2" mean that the organic polymer is powdered in advance; part of the organic polymer is powdered and mixed with the pelletized organic polymer; extruder conditions as described above. coarse powder is cut from the black pigment; the black pigment is not excessively contained; and the like.

Evaluation example 3
<Evaluation of filament yarn>
<<Measurement of color tone and spectral curve of thread>>
Based on "JIS L1013:2010 Chemical fiber filament thread test method", the thread was wound around a sample plate of 5 cm x 5 cm to obtain a measurement sample. The winding amount was 0.8 g.
In order to conduct the heat storage test in Evaluation Example 4 using the same measurement sample, a galvanized steel plate was used as the sample plate.

As a control (comparison), a 30% by mass carbon black masterbatch was used, and 1.2 parts by mass (4.0 parts by mass of the masterbatch) and 0.4 parts by mass (1.3% of the masterbatch) containing A filament yarn was prepared.

Color tone and spectral curve were measured using a spectrophotometer. Table 5 shows the results.
In Table 5, the higher the value of "K/S", the higher the color density, and the lower the value, the higher the color density. Color density is low.
In Table 5, "TSR" is Total Solar Reflectance.

Numerical values in parentheses in Table 5 indicate parts by mass of formulations in a 50% by mass masterbatch.
Those without "*" in the mass parts in parentheses (samples (1) and (2)) use the masterbatch of Production Example 1 (black pigment without coarse powder cut), and the mass parts in parentheses Those with "*" (sample (3)) use the masterbatch of Production Example 2 (black pigment with coarse powder cut).

In addition, FIG. 2 shows the spectral reflectance [%] in the visible light region and the near-infrared light region of the heat-shielding black filament yarns (1), (2), and (3) and the carbon black-containing filament yarn as a control. .

As can be seen from Table 5, samples (1), (2) and (3) were all excellent as "black yarn". In addition, the TSR (total solar reflectance) was higher than that using carbon black, suggesting excellent heat shielding properties.
In particular, sample (3) had a higher K/S than the one using carbon black and a particularly high color density.
In the case of using carbon black, although the hue was good, as shown in FIG. 2 and FIG. 3 of Evaluation Example 4 below, the near-infrared reflectance was low and the heat shielding property was poor.

As can be seen from FIG. 2, the samples (1), (2) and (3) all had high near-infrared reflectance. On the other hand, those using carbon black all had low near-infrared reflectance.
This suggests that the heat-shielding black filament and the heat-shielding black filament yarn of the present invention are superior in heat-shielding properties to the black filament (thread) using carbon black.

In addition, the heat-insulating black filament and the heat-insulating black filament yarn of the present invention did not break. Furthermore, since thread breakage is less likely to occur, it can be contained in a large amount in the organic polymer to improve the blackness.

Evaluation example 4
Using the same sample plate as in Evaluation Example 3 (a sample wound around a galvanized steel sheet with a winding amount of 0.8 g), the heat shielding properties were evaluated (a heat storage test was performed).
Using the filament yarns of Samples (1), (2) and (3) evaluated in Evaluation Example 3, and the carbon black-containing filament yarn evaluated in Evaluation Example 3 as a control, light irradiation was continued for 20 minutes to accumulate heat. A test (temperature rise measurement) was performed. The temperature was measured by attaching a temperature sensor to the opposite side of the sample plate to the light irradiation surface.

Each evaluation was performed with n=5. The "five arithmetic mean values" and the "standard deviation (SD)" of the sample temperature after 20 minutes were determined.
The results are shown in Table 6 and FIG.

The numbers in parentheses in Table 6 indicate the parts by weight of the formulation in the 50% by weight masterbatch.
Those without "*" in the mass parts in parentheses (samples (1) and (2)) use the masterbatch of Production Example 1 (black pigment without coarse powder cut), and the mass parts in parentheses Those with "*" (sample (3)) use the masterbatch of Production Example 2 (black pigment A with coarse powder cut).

As can be seen from Table 6 and FIG. 3, the filament yarns of the samples (1), (2) and (3) of the present invention all have a lower temperature rise than the filament yarn using carbon black, and have excellent heat shielding properties. It was a thing.
In particular, the filament yarn of sample (3) had a sample temperature as low as 9.4 ° C. after 20 minutes compared to the “control filament yarn containing carbon black” (see Table 6 and FIG. 3), indicating heat-shielding properties. was extremely excellent.

Production example 4
<Change black pigment>
Production Examples 1, 2, A masterbatch, filaments, and filament yarns were produced in the same manner as in 3, and evaluated in the same manner as in Evaluation Examples 1 to 4.

Production example 5
<Change black pigment>
A masterbatch was prepared in the same manner as in Production Examples 1, 2, and 3, except that "Black 6340" (chromium Iron Oxide) (CAS No. 12737-27-8) manufactured by Asahi Kasei Kogyo Co., Ltd. was used as the black pigment. , filaments and filament yarns were produced and evaluated in the same manner as in Evaluation Examples 1-4.

Production example 6
<Change dispersing agent>
A masterbatch, a filament, and a filament yarn are produced in the same manner as in Production Examples 1, 2, and 3, except that ethylenebisbehenamide is used instead of ethylenebisstearicamide, which is a dispersing aid in Production Example 1. and evaluated in the same manner as in Evaluation Examples 1 to 4.

Evaluation example 5
The masterbatches, filaments, and filament yarns obtained in Production Examples 4, 5, and 6 were evaluated in the same manner as in Evaluation Examples 1 to 4, and almost the same results as in Evaluation Examples 1 to 4 were obtained. It was found that both of them are excellent in heat storage test and excellent in heat shielding property. In addition, neither filament breakage nor thread breakage occurred.

Production example 7
<Production of sheet for preliminary evaluation>
The sample (3) of Production Example 3, that is, the filament yarn prepared using the masterbatch produced using the "coarse-cut black pigment" (black pigment A) (see FIG. 4) in Production Example 2, As described above, although the amount of black pigment was large, fibers that looked black to the naked eye were obtained without any trouble of yarn breakage.
However, when the semi-drawn yarn (POY) was re-drawn to produce the drawn yarn (FDY), the strength of the yarn was slightly low, and the yarn was broken in some cases.
This phenomenon was the same even when the blending amount of the masterbatch was reduced to relatively lower the ratio of the black pigment.

Considering that the cause of this slight lack of strength lies in the particle size of the black pigment, the particle size of the black pigment was made smaller.
Coarse powder is cut in the same manner as black pigment A, and a black pigment having a particle size smaller than that of black pigment A of Production Example 2 (i.e., sample (3) of Production Example 3) is prepared, "black pigment B". , and its particle size distribution is shown in FIG.
The median diameter (D50) of black pigment B was 0.486 µm (Fig. 5). As described above, the median diameter (D50) of black pigment A was 0.750 μm (FIG. 4).

However, since the hue of the black pigment B shifted toward reddish brown compared to the heat shielding pigment A, a color tone modifier was added to further improve the blackness. In addition, if the blackness is further improved, the application will be further expanded.

A preliminary simulation (preliminary evaluation) was performed using a sheet using a polyvinyl chloride (PVC) compound in order to proceed with color tone adjustment in a simple manner. The reason why the compound containing titanium was used was that the difference in color development between the yarn and the PVC sheet was considered.

In order to confirm whether or not the heat shielding property is lowered when the color tone is adjusted, a test was conducted by combining various color tone adjusting agents.
In this preliminary evaluation, the polymer to be dispersed is not a fiber polymer such as PET but polyvinyl chloride (PVC); the shape to be dispersed is a sheet rather than a filament or thread; However, it is common technical knowledge and has been confirmed that the reflectance spectrum of near-infrared light, TSR (total solar reflectance), etc. tend to be the same.
Therefore, regarding the heat shielding property, which correlates with such physical properties, the evaluation results of the sheet can be applied (analogously) to filaments and threads, even if the shape and the organic polymer are different.

Evaluation example 6
<Preliminary evaluation on sheet (color tone, reflectance of near-infrared light (spectrum, TSR)>
The formulation is shown in Table 7 below.
Further, the obtained sheet was measured with a spectrophotometer, color tone was compared, and the TSR value was obtained. The results are shown in Table 8 below.
The unit of numerical values in Table 7 is "parts by mass".
In Tables 7 and 8, "heat-shielding pigment" means "black pigment", "heat-shielding A" and "heat-shielding pigment A" mean "black pigment A", and "heat-shielding pigment B" means It means "black pigment B" and "CB" means carbon black.

As can be seen from Tables 7 and 8, it was found that the total solar reflectance (TSR) was not significantly affected even when the color tone modifier was blended.
That is, the TSR of "black pigment A is 5% (5 parts by mass)" is 27.20, and the TSR of "black pigment A is 10% (10 parts by mass)" is 26.67, Since the TSR of "8 parts by mass of black pigment A, 2.05 parts by mass of P.BL-15:3, and 0.51 parts by mass of P.Y-95 NO.8" was 25.56 , the TSR decreased by only about 2% at most.

In addition, the reflectance (spectrum) of near-infrared light was measured for all of the above sheets (Fig. 6). % to 6% (see Figure 6).
On the other hand, NO. 1 to 8 are all 14% to 81% in the range of 780 nm to 2500 nm (wavelength range of "near infrared light"), particularly 40% to 81% in the range of 1100 nm to 2200 nm. (See Figure 6).

In addition, in FIG. 6, "CB" means carbon black.

If a "pigment other than carbon black (CB)" is blended (mixed) as a color tone modifier, the TSR does not decrease significantly, and the reflectance at the wavelength of near-infrared light does not decrease. It was found that there is little possibility that the blending (mixing of colors) of the color tone adjusting agent has an adverse effect on the deterioration of the heat shielding properties.

Also, from a comparison of the No. 7 and No. 8 sheets, it was found that the sheet using the black pigment B was more likely to produce a reddish or yellowish color tone than the black pigment A, and the TSR was also high.
It was found that the color tone can be adjusted by changing the particle size distribution of the black pigment or by adding a color tone adjusting agent.

Evaluation example 7
<Preliminary evaluation of sheet (heat shielding property)>
"CB 1.2%" (carbon black 1.2% by mass), "heat shielding A 10%" (black pigment A 10% by mass), "No .3”, “No. 6” and “No. 7” were evaluated for heat shielding properties.
Although this preliminary evaluation is an evaluation of the heat-shielding property of a polyvinyl chloride (PVC) sheet, it is clear that there is a correlation with the evaluation of the heat-shielding property of filaments and threads such as PET, which are commonly used as fibers.

The TSR from 300 nm to 2100 nm is
"CB 1.2%" (1.2% by mass of carbon black) is 5.18,
"Heat shield A 10%" (10% by mass of black pigment A) is 26.67,
"No. 3" is 27.33,
"No. 6" is 28.64,
"No. 7" was 28.67.

The heat shielding property was evaluated in the same manner as in Evaluation Example 4 (a heat storage test was conducted).
The results are shown in FIG.

As can be seen from FIG. 7, in the heat storage test for 20 minutes, No. 3, 6, and 7 were found to suppress the rise in temperature (41° C. or less), similar to “Heat Shielding A 10%” (10% by mass of black pigment A).
On the other hand, it was found that "CB 1.2%" (1.2% by mass of carbon black) did not suppress the temperature rise (54°C).

Production example 8
<Production of sheet for production of filament containing color tone modifier>
In Evaluation Examples 6 and 7, it was found that the mixed color of pigments other than carbon black (CB) (containing organic pigments) sometimes did not reduce the heat shielding properties. The following evaluations were performed using a pigment suitable for polyester fibers as a color tone modifier.
Considering the dispersibility in the PET resin, the organic pigment used was P.I. BL-15:3 (74160) and P. Y-147 (60645) was used.
The compositions are shown in Table 9 below. Numerical values in Table 9 indicate "mass parts".

Evaluation example 8
<Evaluation of sheet obtained in Production Example 8 (color tone, reflectance of near-infrared light (spectrum), TSR)>
The color tone, near-infrared reflectance (spectrum), and TSR of the sheet obtained in Production Example 8 were measured and evaluated.
The color tone is shown in Table 10 below, and the near infrared reflectance (spectrum) is shown in FIG.

From the results in Table 10 and FIG. 8, all of them were excellent in color tone and blackness, and excellent in near-infrared light reflectance.
Therefore, it was found that the inclusion of an organic pigment as a color tone adjusting agent can increase the blackness (blackness and color (color tone)) of the filament (thread) while maintaining its heat shielding properties.

Production example 9
<Production and evaluation of drawn yarn (FDY)>
Regarding the combined use of a black pigment and an organic pigment, up to Production Example 8 and Evaluation Example 8, it was an alternative test with a sheet, but actually produced a drawn yarn (FDY) and measured "thread breakage" and "blackness". "Thermal insulation" was evaluated.

<<Preparation of masterbatch>>
Among the above-described sheet compositions, No. 1 was expected to have a good color tone and a high temperature rise suppression effect from the TSR value. A masterbatch was made with 12 compositions.
Table 11 below shows the compositions of the prepared masterbatches "MB(1)" and "MB(2)". The numbers in Table 11 indicate parts by mass.

In Table 11, "powder PET" is obtained by dry pulverizing pellet PET using a turbo disk mill as described in Production Example 1.
"PBT" in Table 11 is polybutylene terephthalate.
MB(1) was prepared using a single black pigment for comparison with the black pigment A used in the preparation of the previous FDY.

Evaluation example 9
By using only powdered PET and powdered PBT without using pelletized polymer, segregation could be further suppressed.
Moreover, by combining PBT and lowering the melt viscosity of the masterbatch, the dispersibility was further improved. In addition, since the masterbatch is easily melted in the natural resin during spinning, the diffusibility of the masterbatch can be increased, and yarn breakage can be further suppressed.
If the diffusibility of the masterbatch is poor, there will be places in the yarn where the concentration of the black pigment is high, and the yarn will break due to variations in stretchability and the like.

As a result of increasing the amount of the dispersing aid in MB (2), the dispersibility of the black pigment did not deteriorate even when the organic pigment was mixed.
However, the content of the dispersing agent (ethylene bis-stearic acid amito) was suppressed to 0.7% by mass in order to suppress slippage due to excessive activity during extrusion melting during spinning.

Production example 10
<Preparation of filament (thread) and woven fabric>
A 2-denier multifilament semi-drawn yarn (POY) was prepared in the same manner as described above with the composition shown in Table 12 below, a drawn yarn was produced, and a woven fabric was produced using the yarn.
As the natural resin, the same PET (pellet-shaped material) as used in the production of the masterbatch was used.
The values in Table 12 are parts by mass.

Evaluation example 10
The filament, semi-drawn yarn, drawn yarn, and woven fabric obtained in Production Example 10 have excellent hue and blackness, and have excellent near-infrared reflectance from the TSR value, The effect of suppressing temperature rise was high. That is, the filament, semi-drawn yarn, drawn yarn, and woven fabric exhibited excellent blackness and heat-shielding properties.

It was found that even in the state of filaments, half-drawn yarns, drawn yarns, and woven fabrics, blackness can be improved while maintaining heat-shielding properties by using a color tone adjusting agent in combination. In general, when a woven fabric is used, the blackness deteriorates sensuously, but in the above study, sufficient blackness was obtained.
Compared to the filament (thread) obtained using the masterbatch of Production Example 2 (no color tone modifier), further blackness (jet-blackness) was observed.

In addition, the black pigment B had coarse powder cut off and had a good particle size distribution, so that it had good dispersibility, and there was no filament breakage (thread breakage).

The ``black filament for heat shielding in which ``a metal composite oxide, etc.'' is dispersed and included in the organic polymer of the present invention has a high reflectance of near infrared rays (780 nm to 2500 nm) and blackness (jet blackness). Since it is similar to carbon black, although it is black, it can suppress temperature rise.
Therefore, it is widely used in the fields of manufacture and application of members, materials, structures, etc., where it is desired to suppress the temperature rise.

Claims (12)

A heat-shielding black filament comprising a black pigment contained in an organic polymer in a dispersed state,
The black pigment is a metal oxide or a metal composite oxide,
A black filament for heat shielding, characterized in that the filament has a thickness of 10 denier or less. 2. The black filament for heat shielding according to claim 1, wherein the organic polymer is an organic polymer for synthetic fibers. At least one black pigment selected from the group consisting of zinc (Zn), chromium (Cr), titanium (Ti), manganese (Mn), antimony (Sb), iron (Fe), and bismuth (Bi) 3. The heat-shielding black filament according to claim 1, which is a metal composite oxide containing the above-described metal elements. 4. The black pigment according to any one of claims 1 to 3, wherein the black pigment is contained in the organic polymer in an amount of 5% by mass or more and 20% by mass or less with respect to the entire heat-shielding black filament. black filament for heat shielding. 5. The heat-shielding black filament according to any one of claims 1 to 4, having an average reflectance of 10% or more in the entire wavelength range of near-infrared light. 6. The heat-shielding black filament according to any one of claims 1 to 5, wherein in addition to the black pigment, a color tone adjusting agent is contained inside the organic polymer. A masterbatch for producing the heat shielding black filament according to any one of claims 1 to 6,
The masterbatch, wherein the black pigment is contained in the organic polymer in a dispersed state in an amount of 20% by mass or more and 80% by mass or less with respect to the entire masterbatch. 5 or more and 50 or less of the heat-shielding black filaments according to any one of claims 1 to 6 are twisted or bundled. thread. A method for producing a masterbatch according to claim 7,
A method for producing a masterbatch, wherein the organic polymer is heated and melted, and the black pigment is contained in the melted organic polymer and kneaded to form a dispersed state. 10. The method for producing a masterbatch according to claim 9, wherein the organic polymer is pulverized to a volume average diameter of 1000 [mu]m or less, put into a kneader, and kneaded together with the black pigment. 11. The method for producing a masterbatch according to claim 9 or 10, further comprising blending and kneading a long-chain fatty acid amide as a dispersing aid. 12. A method for producing a heat-shielding black filament, wherein the method for producing a masterbatch according to any one of claims 9 to 11 is used.

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