Infrared radiation resin composition

Abstract

To provide an infrared radiation resin composition containing an infrared radiation material capable of emitting radiation with high emissivity, uniformity, and stability in a predetermined wavelength range. 【Solution means】An infrared radiation resin composition containing an infrared radiation material and a resin, wherein the infrared radiation material contains conductive carbon black and gold nanoparticles, and in the infrared radiation material, the mass ratio of conductive carbon black to gold nanoparticles is 99.95:0.05 to 99.999:0.001.

Description

Technical Field

[0001] The present invention relates to an infrared radiation resin composition. In particular, the present invention relates to an infrared radiation resin composition used for drying various materials, imparting functional properties such as heat retention to clothing, etc., air conditioning, and hair and beauty care.

Background Art

[0002] Conventionally, as infrared radiation materials, ceramics containing alumina, titania, zirconia, silica, etc. have been proposed. Such materials radiate infrared rays, and when the infrared rays are absorbed by a substance, the substance is heated.

[0003] Water molecules perform vibrational motions such as stretching and angular variation. When water molecules absorb infrared rays, they are excited to a high vibrational state. As a result, the temperature of the water molecules increases. Therefore, substances containing water molecules, the human body, animals and plants, etc. increase in temperature when they absorb infrared rays.

[0004] Therefore, in order to efficiently warm substances containing water molecules, the human body, animals and plants, etc., it is necessary to use an infrared radiation material that radiates infrared rays having a wavelength capable of exciting the vibrational motion of water molecules. As such an infrared radiation material, the present inventors have proposed, in Patent Document 1, an infrared radiation material that can radiate infrared rays that are easily absorbed by animals and plants such as the human body.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] When an infrared radiation material is applied to, for example, fibers used in clothing, the infrared radiation material needs to absorb infrared rays radiated from the human body wearing the clothing, store heat, and radiate the stored heat energy as infrared rays to the human body. That is, the infrared radiation material is required to absorb infrared rays radiated from other substances, store heat, and efficiently radiate the stored heat energy as infrared rays.

[0007] However, the infrared radiation material described in Patent Document 1 had a problem that, for example, the efficiency of absorbing and storing heat from infrared rays radiated from a human body or the like was not sufficient. As a result, when the stored heat energy was radiated as infrared rays, the radiation efficiency in the wavelength range (for example, 4 to 20 μm) that was easily absorbed by animals and plants such as the human body was not uniform, and there was a problem that the absorption and radiation of infrared rays by animals and plants such as the human body were insufficient.

[0008] In view of such a situation, the present invention aims to provide an infrared radiation resin composition containing an infrared radiation material capable of highly and uniformly radiating with stability in a predetermined wavelength range.

Means for Solving the Problems

[0009] From the above, the aspects of the present invention are as follows.

[0010] [1] An infrared radiation resin composition containing an infrared radiation material and a resin, The infrared radiation material contains conductive carbon black and gold nanoparticles, An infrared radiation resin composition in which, in the infrared radiation material, the mass ratio of conductive carbon black to gold nanoparticles is 99.95:0.05 to 99.999:0.001.

[0011] [2] The infrared radiation resin composition according to [1], wherein the average particle diameter of the conductive carbon black is 10 nm or more and 100 nm or less.

[0012] [3] The infrared radiation resin composition according to [1] or [2], wherein the gold nanoparticles are particles having an irregular shape.

[0013] [4] The infrared radiation resin composition according to any one of [1] to [3], wherein the gold nanoparticles are spike-shaped gold nanoparticles and the average particle diameter of the gold nanoparticles is 10 nm or more and 700 nm or less.

[0014] [5] The infrared radiation resin composition according to any one of [1] to [3], wherein the gold nanoparticles are rod-shaped gold nanoparticles, the average diameter of the gold nanoparticles is 10 nm or more and 50 nm or less, and the average length is 20 nm or more and 250 nm or less.

[0015] [6] The infrared radiation resin composition according to any one of [1] to [5], wherein the infrared radiation resin composition is plate-shaped, cylindrical, or sheet-shaped, and the infrared radiation material is dispersed in the resin.

[0016] [7] The infrared radiation resin composition according to any one of [1] to [5], wherein the infrared radiation resin composition is fibrous and the infrared radiation material is dispersed in the resin.

[0017] [8] The infrared radiation resin composition according to [6], wherein the infrared radiation material is contained in an amount of 5 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the resin.

[0018] [9] The infrared radiation resin composition according to [7], wherein the infrared radiation material is contained in an amount of 0.5 parts by mass or more and 2 parts by mass or less per 100 parts by mass of the resin.

Advantages of the Invention

[0019] According to the present invention, it is possible to provide an infrared radiation resin composition containing an infrared radiation material capable of highly radiating, uniformly and stably radiating in a predetermined wavelength range.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, the present invention will be described in detail in the following order based on specific embodiments. 1. Infrared Radiation Resin Composition 1.1. Infrared Radiation Material 1.2. Conductive Carbon Black 1.3. Gold Nanoparticles 2. Method for Producing Infrared Radiation Resin Composition

[0022] (1. Infrared Radiation Resin Composition) The infrared radiation resin composition according to the present embodiment has an infrared radiation material and a resin. The infrared radiation material is preferably in powder form, and in the infrared radiation resin composition, it is preferable that the infrared radiation material powder is dispersed in the resin. The infrared radiation material will be described later.

[0023] As the resin, known resins can be used according to the application of the infrared radiation resin composition. Examples of known resins include thermoplastic resins such as polyester, polyethylene, polypropylene, polystyrene, polycarbonate, polyurethane, acrylic, nylon, polylactic acid-based resins, and epoxy resins; thermosetting resins such as melamine resins and urea resins; rubbers such as natural rubber and synthetic rubber; and recycled resins such as rayon. In this embodiment, polypropylene and polyethylene of the polyolefin type; polyethylene terephthalate of the polyester type; nylon, etc. are preferably used.

[0024] The infrared radiation resin composition is molded into various shapes according to the application and then used. In this embodiment, the infrared radiation resin composition is preferably in a plate shape, a cylindrical shape, a sheet shape, or a fibrous shape, and more preferably in a fibrous shape. In the fibrous infrared radiation resin composition, the infrared radiation material is dispersed in the fibrous resin.

[0025] The fibrous infrared radiation resin composition is made fibrous by a spinning process. Such fibers are chemical fibers artificially manufactured using chemical methods. Chemical fibers include fibers other than natural fibers, for example, synthetic fibers (polyester-based, polyamide-based), semi-synthetic fibers (cellulose-based), recycled fibers (cellulose-based), etc.

[0026] The blending ratio of the infrared radiation material and the resin may be set according to the application. In this embodiment, when the infrared radiation resin composition is in a plate shape, a cylindrical shape, or a sheet shape, it is preferable that the infrared radiation material is 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the resin. Also, when the infrared radiation resin composition is in a fibrous shape, it is preferable that the infrared radiation material is 0.5 parts by mass or more and 2.0 parts by mass or less with respect to 100 parts by mass of the resin.

[0027] (1.1. Infrared Radiation Material) An infrared radiation material is a material that emits infrared rays. In this embodiment, in particular, it is preferably a material that emits infrared rays having a wavelength suitable for exciting water molecules contained in substances, the human body, animals and plants, etc. Further, the infrared radiation material is preferably a material having a high infrared radiation rate in the wavelength range of 5 μm to 20 μm, particularly preferably in the range of 7 μm to 14 μm. The infrared radiation rate can be measured using a Fourier Transform Infrared Spectroscopy (FTIR), for example, based on a measurement method approved by the Far Infrared Association.

[0028] In this embodiment, the infrared radiation material contains conductive carbon black and gold nanoparticles. Further, in the infrared radiation material, the mass ratio of conductive carbon black to gold nanoparticles is 99.95:0.05 to 99.999:0.001.

[0029] When the mass ratio of conductive carbon black to gold nanoparticles is within the above range, the absorption and radiation rate of the infrared radiation thermal energy of the infrared radiation material can be increased. Therefore, the infrared radiation rate of the infrared radiation material according to this embodiment can be increased, and furthermore, the infrared radiation rate can be made uniform in the wavelength range of 5 μm to 20 μm.

[0030] The mass ratio of conductive carbon black to gold nanoparticles is preferably 99.98:0.02 to 99.998:0.002.

[0031] (1.2. Conductive Carbon Black) Carbon black is an aggregate of almost pure carbon fine particles. The aggregate of the minimum unit of carbon black is a network plane (plate) in which about 30 to 40 six-membered carbon rings are bonded two-dimensionally. Crystallites are formed by stacking these network planes approximately at equal intervals for 3 to 5 layers. And 1,000 to 2,000 crystallites aggregate to form one primary particle. Furthermore, several tens of primary particles aggregate and chemically and physically bond to each other to form secondary particles. The size of the particle connection in the secondary particles is called structure, which affects the physical properties of carbon black.

[0032] The carbon black contained in the infrared radiation material according to this embodiment is conductive carbon black. The conductivity exhibited by conductive carbon black is expressed by the movement of π (pi) electrons on the six-membered carbon ring on the particle surface to form a conductive path. In particular, carbon black with a high structure having a wide and large secondary structure of the structure and a network structure in the medium exhibits excellent conductive performance.

[0033] The manufacturing method of conductive carbon black is not particularly limited, and a known manufacturing method of carbon black is adopted. Examples of known methods include the oil furnace method, the acetylene method, the gasification method, etc. For example, in the oil furnace method, hydrocarbons as raw materials are pyrolyzed by the combustion heat of oil or gas to produce carbon black. In the acetylene method, carbon black is produced by pyrolyzing acetylene. In the gasification method, carbon black is produced by utilizing the gasification process of heavy oil.

[0034] In this embodiment, the average particle diameter of the primary particles of conductive carbon black is preferably 10 nm or more and 100 nm or less, and more preferably 15 nm or more and 70 nm or less. In this embodiment, the average particle diameter of the primary particles of carbon black is a value calculated from the arithmetic average diameter obtained by observing the primary particles with an electron microscope.

[0035] Examples of commercially available conductive carbon blacks include "No. 3230B" manufactured by Mitsubishi Carbon Black, "No. 3030B" manufactured by Mitsubishi Carbon Black, "Denka Black" (powdered product) manufactured by Denka Co., Ltd., "Ketjen Black EC600JD" manufactured by Lion Specialty Chemicals, and the like.

[0036] (1.3. Gold Nanoparticles) Gold nanoparticles are an aggregate of gold fine particles having a particle diameter of 1 to 1000 nm. On the surface of gold nanoparticles, among the light irradiated to the particles, light of a specific wavelength interacts with the electrons on the particle surface, resulting in a collective vibration phenomenon of electrons called surface plasmon resonance (SPR).

[0037] The wavelength of the interacting light changes depending on the difference in the shape of the gold nanoparticles. This is due to the anisotropic (non-uniform) distribution of the surface electron layer of the gold nanoparticles. For example, spherical gold nanoparticles have a maximum absorption at a wavelength of 515 to 570 nm. On the other hand, gold nanoparticles having an irregular shape other than spherical have a red shift in the absorption wavelength to the longer wavelength side compared to spherical gold nanoparticles, and have a maximum absorption in the infrared region. As a result, the electromagnetic field due to surface plasmons is enhanced, and the absorption and radiation of light are strengthened. As a result, the infrared emissivity increases. Therefore, in the present embodiment, the gold nanoparticles are preferably gold nanoparticles having an irregular shape. Further, the gold nanoparticles having an irregular shape are preferably not surface-modified.

[0038] Examples of gold nanoparticles having an irregular shape include rod-shaped gold nanoparticles (gold nanorods) and spike-shaped gold nanoparticles (gold nanoarches, gold nanostars).

[0039] The size of the gold nanorods is preferably such that the diameter (minor axis diameter) is 10 nm or more and 50 nm or less, more preferably 10 nm or more and 40 nm or less. The length (major axis diameter) is preferably 20 nm or more and 250 nm or less, more preferably 60 nm or more and 180 nm or less. Further, the aspect ratio of the gold nanorods is more preferably 2 or more and 5 or less, even more preferably 3 or more and 4 or less. In this embodiment, the diameter and length are the values measured by the laser diffraction method.

[0040] The size of the gold nanoarchin is preferably such that the average particle diameter is 10 nm or more and 700 nm or less, more preferably 15 nm or more and 650 nm or less, even more preferably 20 nm or more and 600 nm or less. The average particle diameter is the value measured by the laser diffraction method.

[0041] Examples of commercially available products of irregularly shaped gold nanoparticles include "Gold Nanorods A12-10-2100" manufactured by Nanopartz, "Gold Nanorods A12-25-1400" manufactured by Nanopartz, "Gold Nanoarchin GU-100" manufactured by Cytodiagnostics, and the like.

[0042] (2. Method for producing infrared radiation resin composition) The infrared radiation resin composition according to this embodiment is obtained as a mixture by mixing a resin and an infrared radiation material. In the mixture, it is preferable that the infrared radiation material is dispersed in the resin. It is desirable that the infrared radiation material is uniformly dispersed in the resin at the nanometer level to the micrometer level. Due to this dispersibility, the infrared radiation rate is improved and the energy loss is reduced.

[0043] The mixing of the resin and the infrared radiation material is carried out, for example, by melt-kneading the resin and the infrared radiation material using a known kneader. Examples of known kneaders include mixers, kneaders, rolls, extruders, etc. Further, the mixture of the resin and the infrared radiation material may be obtained by preparing a masterbatch containing the infrared radiation material at a high concentration and kneading the masterbatch with the remaining resin raw material.

[0044] In this embodiment, the obtained infrared radiation resin composition is preferably formed into a predetermined shape according to the application. The forming of the infrared radiation resin composition may be carried out simultaneously with the above mixing.

[0045] When forming the infrared radiation resin composition into a plate shape, a cylindrical shape, or a sheet shape, it is preferable to use a forming method such as injection molding, extrusion molding, T-die molding, or calendar molding. Further, when forming the infrared radiation resin composition into a fibrous shape, it is preferable to use a spinning method such as melt spinning, dry spinning, wet spinning, or centrifugal spinning. The infrared radiation resin composition formed into a fibrous shape is processed, for example, into a fabric, a knitted fabric, a non-woven fabric, a felt, a punching sheet, etc.

[0046] The infrared radiation resin composition can be used as clothing, medical materials, building materials, and vehicle interior materials, and is particularly preferably used as clothing and bedding for thermotherapy using infrared rays.

[0047] As described above, the embodiments of the present invention have been described, but the present invention is not limited to the above embodiments at all, and may be modified in various ways within the scope of the present invention.

Examples

[0048] Hereinafter, the invention will be described in more detail using examples, but the present invention is not limited to these examples.

[0049] (Test 1) As raw materials for the infrared radiation material, conductive carbon black (「#3230B」manufactured by Mitsubishi Carbon Black) and gold nanoparticles (「Gold Nanoarchin GU-100」manufactured by Cytodiagnostics and 「Gold Nanorod A12-10-2100」manufactured by Nanopartz) were prepared. The average particle diameter of the primary particles of the conductive carbon black was 55 nm, the average particle diameter D50 of the gold nanoarchin was 100 nm, the average diameter of the gold nanorod was 110 nm, and the average length was 175 nm.

[0050] The prepared conductive carbon black and gold nanoparticles were mixed at the compounding ratios shown in Table 1 to obtain an infrared radiation material.

[0051]

Table 1

[0052] The obtained infrared radiation material was compounded so that the ratio of the total mass of the conductive carbon black and gold nanoparticles to the mass of the polyethylene resin was 1:9, and using a kneader (「Plasticorder Lab Station W50EHT type」manufactured by Brabender), kneading was performed at a rotational speed of 50 rpm and a resin temperature of 180 °C for 10 minutes to obtain pellets.

[0053] For the obtained pellets, hot pressing was performed using a press molding machine (manufactured by Toho Press Manufacturing Co., Ltd.) under the conditions of a heating temperature of 200 °C and a gauge pressure of 10 Mpa to obtain a sheet-like infrared radiation resin composition having dimensions of 100 mm × 100 mm × 0.6 mm.

[0054] Regarding Comparative Example B-4, it was compounded so that the mass ratio of the mass of the gold nanoparticles to the mass of the polyethylene resin was 0.05:99.95, and in the same manner as above, a sheet-like infrared radiation resin composition was obtained. Also, regarding Comparative Example B-5, as a blank, in the same manner as above, a sheet-like resin composition composed only of polyethylene resin without containing an infrared radiation material was obtained.

[0055] The infrared spectral emissivity of the obtained infrared radiation resin composition was measured as follows. A test piece measuring 40 mm × 40 mm was cut out from the obtained sheet-like infrared radiation resin composition, and using an infrared spectral emissivity measuring machine ("SpectrumOne Frontier T" manufactured by PerkinElmer), the infrared spectral emissivity was measured in the infrared wavelength range (5 to 20 μm) by the FT-IR method under the conditions of measurement temperature: 40°C, ambient temperature: 20°C, and humidity: 65%. Also, the infrared spectral emissivity of the blank sample was measured under the above conditions. From the measurement results, when calculating the average emissivity of the blank in the infrared wavelength range (7 to 14 μm), it was 86.1%.

[0056] In this example, considering the criteria of the evaluation item "radiation characteristics, spectral emissivity" in the "Infrared Fiber Product Evaluation Criteria" stipulated by the Far Infrared Association, a sample with an average emissivity of 94.7% or more in the infrared wavelength range (7 to 14 μm) was judged to be good. The results are shown in Table 2 and Figures 1 to 3.

[0057]

Table 2

[0058] From Table 2 and Figures 1 to 3, it was confirmed that when the infrared radiation material contains the above-mentioned components and the content is within the above-mentioned range, a high average emissivity and a uniform infrared radiation resin composition can be obtained.

[0059] (Test 2) As raw materials for the infrared radiation material, conductive carbon black ("#3030B" manufactured by Mitsubishi Carbon Black) and gold nanoparticles ("Gold Nanorods A12-25-1400" manufactured by Nanopartz) were prepared. The average particle size D50 of the conductive carbon black was 55 nm, the average diameter of the gold nanorods was 25 nm, and the average length was 245 nm.

[0060] The prepared conductive carbon black and the mass of the gold nanoparticles were mixed so that the mass ratio became 99.99:0.01 to obtain an infrared radiation material. The infrared radiation material and the nylon resin were blended so that the mass ratio became 1:9, and kneading was performed using a resin melting and kneading apparatus ("50C type 150" manufactured by Toyo Seiki Co., Ltd.) under the conditions of a heating temperature of 270°C and a rotation speed of 100 rpm to prepare a masterbatch A3M-1.

[0061] Next, the obtained masterbatch A3M-1 and the nylon resin were blended so that the mass ratio became 1:9, and using a multifilament production apparatus (manufactured by Musashino Kikai), under the condition of a heating temperature of 280°C, nylon multifilament yarn AMF-1 with a fineness of 88 dtex and 36 filaments was produced by melt spinning.

[0062] The produced nylon multifilament yarn AMF-1 was processed by the POY·DTY method (a method in which by spinning at high speed, partial stretching is performed to obtain POY (Partially Oriented Yarn), and then through the stretching and false twisting process, it becomes DTY (Draw Textured Yarn)). Under the condition of a false twist POY stretching roller winding speed of 4,000 m / min, a POY yarn was made, a twist of 3,200 t / m was applied to the drawn textured yarn DTY, and after heat setting, the twist was removed to process it into a bulky and stretchable yarn.

[0063] The processed AMF-1 was used to produce a fabric using a circular knitting machine and a rib knitting machine (MXC-S3.2 manufactured by Fukuhara Seisakusho Co., Ltd.), and a ribbed T-shirt (AMF-1) was produced.

[0064] Except for using an infrared radiation material blended so that the mass ratio of the conductive carbon black and the mass of the gold nanoparticles became 99.92:0.08, a nylon multifilament yarn BMF-1 was produced by the same method as above, and using the produced nylon multifilament yarn BMF-1, a ribbed T-shirt (BMF-1) was produced.

[0065] Furthermore, a nylon multifilament yarn L-1 was produced in the same manner as above, except that a resin composition made of nylon resin without an infrared radiation material was used, and a knitted cotton T-shirt (L-1) was produced using the produced nylon multifilament yarn L-1.

[0066] According to the test method shown below, the obtained knitted cotton T-shirt was worn, and the heat retention property of the knitted cotton T-shirt was evaluated by measuring the body surface temperature after undressing.

[0067] After the subject entered the laboratory maintained at an indoor temperature of 20°C and an indoor humidity of 65%, the subject sat quietly, and the body surface temperature at the measurement site (back) was measured using a thermograph (FLIR A615 manufactured by FLIR Systems Inc.), and the body surface temperature at the stable time point was taken as the body surface temperature before wearing. After confirmation, the knitted cotton T-shirt produced above was worn and the subject sat quietly, and the knitted cotton T-shirt was undressed after 20 minutes. The body surface temperature of the back immediately after undressing was measured using a thermograph (FLIR A615 manufactured by FLIR Systems Inc.). The results are shown in Table 3 and Figure 4.

[0068]

Table 3

[0069] From Table 3 and Figure 4, it was confirmed that the knitted cotton T-shirt (AMF-1) had high heat retention property.

[0070] (Test 3) As raw materials for the infrared radiation material, conductive carbon black ("#3230B" manufactured by Mitsubishi Carbon Black) and gold nanoparticles ("Gold Nanoarchin GU-100" manufactured by Cytodiagnostics) were prepared. The average particle diameter D50 of the conductive carbon black was 23 nm, and the average particle diameter D50 of the gold nanoarchin was 100 nm.

[0071] The conductive carbon black and the gold nanoparticles were blended so that the mass ratio was 99.995:0.005, and an infrared radiation material (the same blend as Example A-3) was obtained. The infrared radiation material and polyethylene terephthalate (PET) resin were blended so that the mass ratio was 1:9, and kneading was performed using a resin melting and kneading apparatus (Toyosha Seisakusho Co., Ltd. "50C type 150") under the conditions of a heating temperature of 280°C and a rotation speed of 100 rpm to prepare masterbatch AN-1.

[0072] Next, the obtained masterbatch AN-1 and PET resin were blended so that the mass ratio was 1:9, and PET resin staple yarn STA-1 with a fineness of 6.6 dtex and a fiber length of 51 mm was produced by melt spinning under the condition of a heating temperature of 280°C using a short fiber spinning and drawing production apparatus.

[0073] Using the produced staple yarn STA-1 as a raw material, a web was formed using a carding machine (Ikegami Machinery Co., Ltd. "H2DS"). The formed web was laminated in multiple layers using a layer machine (Ikegami Machinery Co., Ltd. "IK30-2"), and it was made into a PET non-woven fabric NWA-1 with a width of 1000 mm and a fabric thickness of 100 g / m 2 by a non-woven fabric needle punching machine (Feller Co., Ltd. "NL21").

[0074] PET resin staple yarn PSB-1 was produced in the same manner as above except that an infrared radiation material obtained by blending the conductive carbon black and the gold nanoarchin so that the mass ratio was 99.5:0.5 was used, and PET non-woven fabric NWB-1 was produced using the produced staple yarn STB-1.

[0075] Furthermore, PET resin staple yarn BL-1 was produced in the same manner as above except that a resin composition made of nylon resin without an infrared radiation material was used, and PET non-woven fabric BL-1 was produced using the produced staple yarn BL-1.

[0076] The temperature change when the produced PET non-woven fabric was heated was measured as follows.

[0077] From the obtained PET nonwoven fabric, a test piece having dimensions of 200 mm × 150 mm was cut out. The cut-out test piece was heated from an upper oblique direction of the test piece using two halogen lamps (CASTER's "CHP-500") arranged to face each other with the test piece sandwiched therebetween, and the average temperature of the test piece (PET nonwoven fabric) from the start of heating to 180 seconds was measured. The output of the halogen lamp was 500 W. The average temperature of the test piece was measured by detecting a spectrum of 7.5 to 14 μm from above the test piece using an infrared camera (FLIR Systems Inc.'s "FLIR SC655"). The results are shown in Table 4 and FIG. 5.

[0078]

Table 4

[0079] From Table 4 and FIG. 5, it was confirmed that the thermal energy radiated from the PET nonwoven fabric NWA-1 was high.

[0080] (Test 4) (In Test 3), the knitted cotton T-shirts (AMF-1) and the knitted cotton T-shirts (Blank L-1) obtained were worn alternately by a total of 4 subjects, 2 men and 2 women, and blood flow data were measured for the case of wearing the knitted cotton T-shirts (AMF-1) and the case of wearing the knitted cotton T-shirts (Blank L-1) by the following method.

[0081] As a blood flow meter, a contact-type probe was used, and a blood flow meter (manufactured by Omega Wave Co., Ltd., Laser Blood Flow Meter OMEGAFLO-Lab) that can continuously measure subcutaneous microcirculation was used to measure the tissue blood flow volume (mL / min / 100g) at a depth of about 1 mm from the subcutaneous surface. Regarding the measurement site, the skin surface of the abdomen covered with a knitted cotton T-shirt was used as the measurement site, and the probe was fixed to the measurement site, and the blood flow volume was measured every 1 second for 30 minutes (1800 seconds) at room temperature of 25°C and humidity of 50%. For each measurement result, a t-test was performed. From the results, when the one-sided value of P(T<=t) is smaller than the significance level (0.05), it was determined that the blood flow volume when wearing AMF-1 was statistically significantly increased compared to the blood flow volume when wearing L-1. The results are shown in Table 5.

[0082] Also, the change rate between the average blood flow volume of the knitted cotton T-shirt (AMF-1) and the average blood flow volume of the knitted cotton T-shirt (blank L-1) was calculated as follows. First, the difference between the average blood flow volume of the knitted cotton T-shirt (AMF-1) and the average blood flow volume of the knitted cotton T-shirt (blank L-1) (the average blood flow volume of the knitted cotton T-shirt (AMF-1) - the average blood flow volume of the knitted cotton T-shirt (blank L-1)) was calculated, and the change rate was calculated by the formula "(difference in average blood flow volume / average blood flow volume of the knitted cotton T-shirt (blank L-1)) × 100". The results are shown in Table 5.

[0083]

Table 5

[0084] From Table 5, from the results of the t-test regarding the average blood flow volume when wearing the knitted cotton T-shirt (AMF-1) and the average blood flow volume when wearing the knitted cotton T-shirt (blank L-1), it was confirmed that wearing the knitted cotton T-shirt (AMF-1) statistically significantly increased the blood flow volume compared to wearing the knitted cotton T-shirt blank (L-1). Also, in accordance with the blood flow improvement regulation in the home-use far-infrared blood circulation promotion clothing for medical device class 1 determined by the Ministry of Health, Labour and Welfare, it was confirmed that the change rate of the average blood flow volume of the subjects was 5% or more.

Industrial Applicability

[0085] Since the infrared radiation resin composition according to the present invention contains an infrared radiation material having a high average value of emissivity in a predetermined wavelength range, it is suitable as a fiber used for clothing etc. that requires heat retention, and as a material used for drying various materials.

Claims

1. An infrared emitting resin composition comprising an infrared emitting material and a resin, the infrared emitting material includes conductive carbon black and gold nanoparticles; In the infrared emitting material, a mass ratio of the conductive carbon black to the gold nanoparticles is 99.95:0.05 to 99.999:0.

001.

2. 2. The infrared radiating resin composition according to claim 1, wherein the conductive carbon black has an average particle size of 10 nm or more and 100 nm or less.

3. 2. The infrared radiating resin composition according to claim 1, wherein the gold nanoparticles are particles having an irregular shape.

4. The infrared radiating resin composition according to claim 3, wherein the gold nanoparticles are spike-shaped gold nanoparticles, and the average particle diameter of the gold nanoparticles is 10 nm or more and 700 nm or less.

5. The infrared radiating resin composition according to claim 3, wherein the gold nanoparticles are rod-shaped gold nanoparticles, and the average diameter of the gold nanoparticles is 10 nm or more and 50 nm or less, and the average length is 20 nm or more and 250 nm or less.

6. 6. The infrared emitting resin composition according to claim 1, wherein the infrared emitting resin composition is in the form of a plate, a cylinder, or a sheet, and the infrared emitting material is dispersed in the resin.

7. 6. The infrared emitting resin composition according to claim 1, wherein the infrared emitting resin composition is in a fibrous form, and the infrared emitting material is dispersed in the resin.

8. The infrared emitting resin composition according to claim 6 , wherein the infrared emitting material is contained in an amount of 5 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the resin.

9. The infrared emitting resin composition according to claim 7 , wherein the infrared emitting material is contained in an amount of 0.5 parts by mass or more and 2 parts by mass or less per 100 parts by mass of the resin.

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