Woven fabric

Abstract

To provide a woven fabric which has an excellent wavelength selective transmission function and is suitably used for obtaining a sunshade sheet in which a temperature of the sunshade sheet itself hardly becomes high due to high light-reflection performance.SOLUTION: A woven fabric is composed of: a tape-like yarn A containing a thermoplastic resin as a main component, having a value of 35% or more obtained by subtracting an infrared transmittance from a visible light transmissivity, and having a light reflectance of 20% or less; a tape-like yarn B containing a thermoplastic resin as a main component and having a light reflectance of 30% or more; and a yarn C containing a thermoplastic resin as a main component. The yarn C constitutes one of a warp and a weft. The tape-like yarn A and the tape-like yarn B constitute the other of the warp and the weft. A ratio (ratio A / ratio B) of a ratio A at which the tape-like yarn A is occupied in an area of the woven fabric and a ratio B at which the tape-like yarn B is occupied the area of the woven fabric is 0.30 to 3.00. The total of the ratio A and the ratio B is 0.700 or more. The yarn C satisfies specific conditions.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to textile fabrics. [Background technology]

[0002] In agriculture, there is a problem of poor growth of agricultural crops and reduced productivity due to deterioration in quality caused by high temperatures in summer. In horticultural greenhouses (hereinafter sometimes referred to as greenhouses), the temperature inside the greenhouse rises, and the risk of workers suffering from sunstroke or heat stroke is increasing year by year due to the recent rise in temperature caused by climate change. To address these issues, the conventional approach has been to cover the outside of the greenhouse with a sunshade sheet to suppress the rise in temperature inside the greenhouse caused by sunlight.

[0003] When a conventional sunshade sheet is used to cover a greenhouse, it blocks infrared rays, which are heat rays, but at the same time, it blocks visible light, which is necessary for crop growth, creating a trade-off. Therefore, a sunshade sheet with a wavelength selective transmission function that selectively transmits visible light and blocks infrared rays has been proposed.

[0004] Patent Document 1 describes a woven fabric as a sunshade sheet, in which tape-like yarns containing tungsten oxide microparticles having an infrared shielding function are used for at least one of the warp and weft threads, and the total exposed area of ​​the tape-like yarns accounts for 50% or more of the unit area of ​​the fabric. This sheet can block infrared rays over a wide wavelength range, but since the main infrared shielding mechanism is infrared absorption, there is a problem that the sunshade sheet itself becomes hot, and the thermal load on workers who unfold it in a hot environment is large. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2022-59582 Summary of the Invention [Problem to be solved by the invention]

[0006] There is a demand for the development of a sunshade sheet that has an excellent wavelength selective transmission function and is unlikely to become hot due to its high light reflecting performance. In the present invention, the light reflecting performance of the sunshade sheet can be evaluated by the light reflectance, which is the arithmetic average value of the reflectance in the wavelength range of 380 to 2500 nm, and the higher the light reflectance, the better the light reflecting performance. In addition, the heat shielding performance of the present invention is expressed by the solar heat gain coefficient. Although the details will be described later, the solar heat gain coefficient is the ratio of solar energy taken in to the inside of the sunshade sheet, and is the sum of the energy transmitted through the sunshade sheet and the energy absorbed by the sunshade sheet and released to the inside. Therefore, by reducing the energy transmitted through the sunshade sheet (referred to as the solar transmittance in the present invention) or reducing the energy absorbed by the sunshade sheet (referred to as the solar absorptance in the present invention), the solar heat gain coefficient can be reduced, that is, the heat shielding performance can be improved.

[0007] As mentioned above, there is a trade-off between visible light transmittance and solar heat gain coefficient, so for example, if there are two sunshade sheets with the same solar heat gain coefficient but a difference in visible light transmittance, it can be said that the sunshade sheet with the higher visible light transmittance has better wavelength selective transmission function.

[0008] In order to prevent the sunshade sheet itself from becoming too hot, it is important to reduce the amount of energy absorbed by the sunshade sheet, that is, to reduce the solar absorptance.

[0009] In view of these problems, the present invention aims to provide a woven fabric that has excellent wavelength selective transmission function and high light reflecting performance, which is suitable for use in obtaining a sunshade sheet that is less likely to become hot due to the high light reflecting performance. [Means for solving the problem]

[0010] In order to solve the above problems, the woven fabric of the present invention is as follows. That is, (1) Thermoplastic resin as the main component The value obtained by subtracting the infrared transmittance from the visible light transmittance is 35% or more, and Tape-shaped yarn A has a light reflectance of 20% or less. The main component is thermoplastic resin. Tape-shaped yarn B having a light reflectance of 30% or more; It is made of yarn C, whose main component is thermoplastic resin. The yarn C constitutes one of the warp yarn and the weft yarn, The tape-shaped yarn A and the tape-shaped yarn B together constitute the other of the warp and weft yarns. a ratio (proportion A / proportion B) of a proportion A of the woven fabric area occupied by the tape-like yarn A to a proportion B of the woven fabric area occupied by the tape-like yarn B is 0.3 to 3.0; The sum of the ratio A and the ratio B is 0.700 or more, The yarn C is a woven fabric characterized by satisfying at least one of the following conditions (A) and (B): (A) The ratio C of the area of ​​the yarn C overlapping the tape-shaped yarn A to the area of ​​the woven fabric is 0.182 or less. (B) The visible light transmittance of yarn C is 70% or more. Also, (2) it is preferable that the woven fabric according to (1) is characterized in that the tape-shaped yarn A contains at least one selected from the group consisting of tungsten oxide, indium-doped tin oxide, and lanthanum hexaboride; Also, (3) it is preferable that the tape-shaped yarn B is the woven fabric described in (1) or (2), which contains titanium oxide having a number average particle size of 500 to 2500 nm.

[0011] In addition, (4) it is preferable that the woven fabric is one according to any one of (1) to (3), characterized in that at least one surface of the tape-shaped yarn B is a color other than white and yellow. Effect of the Invention

[0012] According to the present invention, it is possible to provide a woven fabric that is suitable for use in obtaining a sunshade sheet that has excellent wavelength selective transmission function and high light reflecting performance so that the sunshade sheet itself does not easily become hot. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic diagram showing an example of a woven fabric according to the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing another example of a woven fabric according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The woven fabric of the present invention can be suitably used for a sunshade sheet and has the following characteristics. That is, the woven fabric of the present invention is composed of tape-shaped yarn A, tape-shaped yarn B, and yarn C. The tape-shaped yarn A is mainly composed of a thermoplastic resin, and has a visible light transmittance minus infrared transmittance of 35% or more, and a light reflectance of 20% or less. The tape-shaped yarn B is mainly composed of a thermoplastic resin, and has a light reflectance of 30% or more. The yarn C constitutes one of the warp and weft threads of the woven fabric of the present invention. In the woven fabric of the present invention, the tape-shaped yarn A and the tape-shaped yarn B together constitute the other of the warp and weft threads, and the ratio (proportion A / proportion B) of the proportion A of the woven fabric area of ​​the tape-shaped yarn A to the proportion B of the woven fabric area of ​​the tape-shaped yarn B is 0.3 to 3.0, and the sum of the proportion A and the proportion B is 0.700 or more. Furthermore, the yarn C satisfies at least one of the following conditions (A) and (B). (A) The ratio C of the area of ​​the yarn C overlapping with the tape-like yarn A to the area of ​​the woven fabric is 0.182 or less. The overlapping area of ​​the yarn C and the tape-like yarn A is 0.182 or less. (B) The visible light transmittance of yarn C is 70% or more.

[0015] The woven fabric of the present invention, which has all of the above-mentioned characteristics, has excellent wavelength selective transmission function, and due to its high light reflecting performance, it has the excellent effect of preventing the woven fabric (sunshade sheet) itself from becoming hot even when used under the blazing sun.

[0016] An embodiment of the present invention will now be described in detail with reference to Fig. 1. Fig. 1 is a schematic diagram showing an example of a woven fabric according to the present invention.

[0017] The woven fabric of the present invention (designated by reference number 1) is composed of tape-like yarn A (designated by reference number 2), tape-like yarn B (designated by reference number 3), and yarn C (designated by reference number 4).

[0018] This tape-shaped yarn A (designated by reference symbol 2) contains thermoplastic resin as its main component, and further has a visible light transmittance minus infrared transmittance of 35% or more and a light reflectance of 20% or less.

[0019] In the present invention, the above-mentioned light rays means light rays having a wavelength range of 380 to 2500 nm, and the above-mentioned light reflectance means the arithmetic mean value of the reflectance in the wavelength range of 380 to 2500 nm.

[0020] Moreover, this tape-shaped yarn B (indicated by reference numeral 3) contains a thermoplastic resin as a main component, and further has a light reflectance of 30% or more.

[0021] Furthermore, this yarn C constitutes the weft of the woven fabric, and the tape-like yarn A and tape-like yarn B together constitute the warp of the woven fabric, and the ratio of the proportion A of the tape-like yarn A in the woven fabric area to the proportion B of the tape-like yarn B in the woven fabric area (proportion A / proportion B) is 0.3 to 3.0, and the sum of the proportion A and the proportion B is 0.700 or more.

[0022] Moreover, this yarn C satisfies at least one of the following conditions (A) and (B). (A) The ratio C of the area of ​​the portion of the yarn C overlapping with the tape-shaped yarn A to the area of ​​the woven fabric is 0.182 or less. (B) The visible light transmittance of yarn C is 70% or more.

[0023] The mechanism by which the woven fabric of the present invention has excellent heat shielding performance against light rays and is unlikely to increase in temperature even when used under the scorching sun is presumed to be as follows. In addition, when the woven fabric has excellent wavelength selective transmission performance and light reflectance performance, the woven fabric has excellent light shielding performance against light rays. That is, the woven fabric of the present invention is characterized in that the value obtained by subtracting the infrared transmittance from the visible light transmittance is 35% or more, and the tape-shaped yarn A having a light reflectance of 20% or less and the tape-shaped yarn B having a light reflectance of 30% or more both constitute one of the warp and weft. The tape-shaped yarn A has the advantage of a wavelength selection function that selectively transmits visible light and blocks infrared rays (shielding here means blocking by absorbing infrared rays, and the same applies below), but the disadvantage that the yarn temperature is likely to increase due to the absorption of light rays. On the other hand, the tape-shaped yarn B may not have a wavelength selective transmission function, but has the advantage of being able to reflect light rays in a wide wavelength range from visible light to infrared rays, and therefore is unlikely to increase in temperature due to the absorption of light rays. Furthermore, since tape-like yarns A and B each constitute one of the warp and weft threads and are parallel to each other, tape-like yarns A and B do not overlap when the fabric is viewed perpendicular to the surface direction of the fabric. However, overlapping of tape-like yarns A and B is not preferable for the following reasons.

[0024] In a portion where tape-like yarn A and tape-like yarn B overlap in the order of light source / tape-like yarn A / tape-like yarn B / inside the house, even if visible light is selectively transmitted by tape-like yarn A, the visible light is reflected by tape-like yarn B, and the amount of visible light that reaches the inside of the house is reduced. Furthermore, tape-like yarn A absorbs both the incident light from the light source and the reflected light by tape-like yarn B, causing tape-like yarn A to generate heat, resulting in an increase in the temperature of the fabric. On the other hand, in a portion where the overlapping order is reversed, that is, in the order of light source / tape-like yarn B / tape-like yarn A / inside the house, a certain amount of visible light and infrared light is reflected by tape-like yarn B, and then the visible light and infrared light that have transmitted through tape-like yarn B are selectively transmitted by tape-like yarn A, resulting in a reduction in visible light transmittance compared to when there is no overlap.

[0025] The yarn C, which is perpendicular to both the tape-like yarn A and the tape-like yarn B, satisfies at least one of the following conditions (A) and (B). (A) The ratio C of the area of ​​the portion of the yarn C overlapping with the tape-shaped yarn A to the area of ​​the woven fabric is 0.182 or less. (B) The visible light transmittance of yarn C is 70% or more. When condition (A) is satisfied, when the woven fabric is viewed perpendicularly to the surface direction of the woven fabric, the area where tape-like yarn A or tape-like yarn B overlaps with yarn C is limited, and therefore, regardless of the visible light transmittance of yarn C, the decrease in visible light transmittance of the woven fabric can be limited. Even when the condition (B) is satisfied, when the woven fabric is viewed perpendicular to the surface direction of the woven fabric, the decrease in visible light transmittance at the points where the tape-shaped yarn A or the tape-shaped yarn B overlaps with the yarn C can be limited.

[0026] In the woven fabric of the present invention, the ratio (ratio A / ratio B) of the proportion A of the woven fabric area occupied by the tape-like yarn A to the proportion B of the woven fabric area occupied by the tape-like yarn B is 0.3 or more. When the ratio (ratio A / ratio B) of proportion A to proportion B is 0.3 or more, the woven fabric can sufficiently obtain the wavelength selective transmission function and can simultaneously achieve a high level of visible light transmittance and light reflectance. More preferably, the ratio (ratio A / ratio B) of proportion A to proportion B is 0.4 or more.

[0027] In addition, the woven fabric of the present invention has a ratio of proportion A to proportion B (proportion A / proportion B) of 3.0 or less. By having the ratio of proportion A to proportion B (proportion A / proportion B) of 3.0 or less, the woven fabric has excellent light reflecting performance, and the woven fabric of the present invention can be prevented from absorbing light and becoming hot. More preferably, the ratio of proportion A to proportion B is 2.2 or less. Methods for setting the ratio of proportion A to proportion B (proportion A / proportion B) within the above range include making the tape-shaped yarn A and the tape-shaped yarn B each have a predetermined width, and warping the tape-shaped yarn A and the tape-shaped yarn B at a predetermined ratio when weaving the fabric.

[0028] In the woven fabric of the present invention, the sum of the above ratio A and the above ratio B is 0.700 or more. When the woven fabric is viewed perpendicularly to the surface direction of the woven fabric, the area where neither the tape-like yarn A nor the tape-like yarn B is present becomes an opening where the yarn C or the yarn is not present, and the solar energy reaches the inside of the house without being blocked. Therefore, the more areas where neither the tape-like yarn A nor the tape-like yarn B is present, the worse the heat shielding performance of the woven fabric of the present invention (sunshade sheet using this woven fabric) becomes. Therefore, by making the area of ​​the areas where neither the tape-like yarn A nor the tape-like yarn B is present less than 0.300, that is, by making the area of ​​the areas where either the tape-like yarn A or the tape-like yarn B is present relative to the unit area of ​​the woven fabric 0.700 or more, the heat shielding performance of the woven fabric of the present invention (sunshade sheet using this woven fabric) as a whole becomes excellent.

[0029] In the woven fabric of the present invention, the sum of the ratio A and the ratio B is preferably 0.971 or less. When the woven fabric is viewed perpendicularly to the surface direction of the woven fabric, the portion where neither the tape-like yarn A nor the tape-like yarn B is present is an opening where the yarn C or the yarn is not present. When the ratio of the opening to the woven fabric when viewed perpendicularly to the surface direction of the woven fabric is 0.025 or more, it is preferable because the woven fabric (sunshade sheet using this woven fabric) is less likely to be blown by the wind when it is spread out. When the ratio of the opening to the woven fabric when viewed perpendicularly to the surface direction of the woven fabric is 0.296 or less, it is preferable in terms of heat shielding performance because the area A or area B can be increased. In addition, when the ratio of the portion of the yarn C that does not overlap with either the tape-like yarn A or the tape-like yarn B when viewed perpendicularly to the surface direction of the woven fabric is 0.004 or more, it is preferable because the mechanical strength of the woven fabric (sunshade sheet using this woven fabric) is high. When the proportion of the portion of yarn C that is not overlapped with tape-like yarn A or tape-like yarn B in the woven fabric viewed perpendicularly to the surface direction of the woven fabric is 0.275 or less, it is possible to increase area A or area B, which is preferable from the viewpoint of heat shielding performance. For these reasons, the sum of proportion A and proportion B is preferably in the range of 0.971 or less.

[0030] Methods for keeping the sum of ratio A and ratio B within the above range include adjusting the width of tape-like yarn A and tape-like yarn B, and adjusting the thread count per unit area of ​​the fabric for tape-like yarn A and tape-like yarn B. Note that the thread count in this invention is a numerical value indicating how many warp threads exist per inch in the width direction of the fabric in the case of warp threads, and is a numerical value indicating how many weft threads exist per inch in the length direction of the fabric in the case of weft threads.

[0031] Next, the tape-shaped yarn A of the woven fabric of the present invention will be described. This tape-shaped yarn A contains a thermoplastic resin as a main component.

[0032] In the present invention, containing a thermoplastic resin as a main component means that the thermoplastic resin is contained in an amount of more than 50 mass% based on the entirety of the tape-shaped yarn A. Specifically, any thermoplastic resin may be used as this thermoplastic resin, such as polyolefin, polyester, methacrylic acid ester, polycarbonate, and mixtures thereof. From the viewpoint of productivity, polyethylene, polypropylene, and polyethylene terephthalate are preferred.

[0033] In this tape-shaped yarn A, the value obtained by subtracting the infrared transmittance from the visible light transmittance is 35% or more. Here, the higher the value obtained by subtracting the infrared transmittance from the visible light transmittance, the more visible light the tape-shaped yarn A transmits and the more infrared rays it blocks. Therefore, it can be said that the higher the value obtained by subtracting the infrared transmittance from the visible light transmittance of the tape-shaped yarn A, the more suitable it is for a woven fabric to be used in a sunshade sheet. One method for making the value obtained by subtracting the infrared transmittance from the visible light transmittance of the tape-shaped yarn A 35% or more is to add an infrared absorbing agent to the tape-shaped yarn A.

[0034] Examples of the infrared absorbing agent include inorganic compounds such as tungsten oxide, antimony oxide, and indium oxide, and organic compounds such as cyanine dyes, phthalocyanine dyes, naphthalocyanine compounds, nickel dithiolein complexes, and azo compounds. The infrared absorbing agent dispersed in a thermoplastic resin has a feature that the visible light transmittance is higher than the infrared transmittance. From the viewpoint of weather resistance, the infrared absorbing agent is preferably an inorganic compound, and more preferably tungsten oxide because it has an excellent ability to block infrared rays of 800 to 1200 nm that are abundant in sunlight, and further, from the above viewpoint, cesium tungsten oxide is more preferable among tungsten oxides. That is, the tape-shaped yarn A preferably contains at least one selected from the group consisting of tungsten oxide, indium-doped tin oxide, and lanthanum hexaboride, more preferably the tape-shaped yarn A contains tungsten oxide, and even more preferably the tape-shaped yarn A contains cesium tungsten oxide.

[0035] When the tape-shaped yarn A contains an infrared absorbing agent, the basis weight of the infrared absorbing agent in the tape-shaped yarn A is determined depending on the intended visible light transmittance and infrared transmittance. From the viewpoint of excellent wavelength selective transmission function, it is preferably 0.2 to 2.5 g / m 2 It is preferable that the thickness is within the range of 0.3 to 2.0 g / m. 2 and more preferably 0.4 to 1.5 g / m 2 and particularly preferably 0.4 to 0.8 g / m 2 It is.

[0036] The tape-shaped yarn A has a light reflectance of 20% or less. The higher the reflectance of infrared rays (wavelength 781 to 2500 nm), the more preferable it is, but if an infrared absorbing agent is added so that the value obtained by subtracting the infrared transmittance from the visible light transmittance is 35% or more, infrared absorption occurs more predominantly than reflection, and the light reflectance becomes 20% or less.

[0037] The thickness of the tape-shaped yarn A is preferably 20 to 200 μm, more preferably 25 to 120 μm, even more preferably 30 to 70 μm, and particularly preferably 30 to 60 μm. By making the thickness 20 μm or more, the tensile strength in the direction parallel to the longitudinal direction of the tape-shaped yarn A can be increased. By making the thickness 200 μm or less, the woven fabric can be made lightweight.

[0038] The width of the tape-shaped yarn A is preferably 1.0 to 20.0 mm, more preferably 2.0 to 10.0 mm, and even more preferably 2.5 to 8.0 mm. By making the width of the tape-shaped yarn A 1.0 mm or more, the number of threads can be reduced, and the productivity can be increased. In addition, the tape-shaped yarn A becomes flat, and twisting of the threads during weaving can be suppressed. By making the width of the tape-shaped yarn A 20.0 mm or less, the tape-shaped yarn A can be easily applied to a general-purpose loom instead of a special loom.

[0039] When the tape-shaped yarn A is uniaxially stretched at a temperature below the melting point and above the softening point of the thermoplastic resin, the orientation and crystallization of the thermoplastic resin are promoted, and the tensile strength in the direction parallel to the tape-shaped yarn A is increased, which is preferable. The stretching ratio is preferably 3 to 15 times, more preferably 5 to 10 times. When the stretching ratio is 3 times or more, the tensile strength can be further increased, and when the stretching ratio is 15 times or less, the tape-shaped yarn A can be prevented from easily splitting in the direction perpendicular to the tape-shaped yarn A. As the method for uniaxial stretching, known methods such as a hot roll method, a hot plate method, and a hot air method can be used.

[0040] The tape-like yarn A may be a single layer consisting of only a base layer, or may be a laminated structure such as a three-layer laminate consisting of a fixing layer, a base layer, and a fixing layer laminated in this order. The fixing layer is a layer that has the function of fixing the contact portion (intersection) of the tape-like yarn A and the yarn C. It is preferable in that it can suppress the occurrence of floating and voids. If the tape-like yarn A and the yarn C are not fixed, or if there is floating or voids even if they are fixed, an air layer is present for the light passing through the woven fabric in a substantially vertical direction, and reflection occurs due to the difference in refractive index at the interface between the tape-like yarn A or the yarn C and the air layer, resulting in a decrease in visible light transmittance, which may result in a decrease in the wavelength selective transmission function of the woven fabric. When the tape-like yarn A and the yarn C are fixed, low-melting thermoplastic resins such as low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE), various adhesives such as acrylic, silicone, and epoxy, and various pressure-sensitive adhesives such as acrylic, silicone, urethane, and rubber can be used as materials for fixing the tape-like yarn A and the yarn C. Among these, it is more preferable to use low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), or a mixture thereof for the fixing layer of the tape-shaped yarn, since it is possible to produce it in one pass by co-extrusion, and it has no tackiness at room temperature and does not require a protective film.

[0041] The base material layer is a layer that functions as a base material when an infrared absorbing agent is contained and that provides the mechanical strength of the tape-shaped yarn A, and can be made of materials such as high density polyethylene (HDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), polypropylene, and polyvinyl chloride.

[0042] When the tape-like yarn A has a laminated structure, the thickness ratio of each of the fixing layer, the base layer, and the fixing layer is preferably 1:98 to 25:50, more preferably 5:90 to 15:70, for the ratio of the thickness of the fixing layer on one side to the thickness of the base layer. Here, by setting the thickness ratio obtained by dividing the thickness of one of the two fixing layers by the thickness of the base layer to 0.01 or more, the fixing of the tape-like yarn A and the yarn C can be strengthened and floating and voids can be reduced. In addition, by setting the thickness ratio obtained by dividing the thickness of one of the two fixing layers by the thickness of the base layer to 0.50 or less, that is, by setting the thickness of the base layer, which is more rigid than the fixing layer, to 2 times or more the thickness of one of the fixing layers, deformation of the tape-like yarn A can be suppressed. In addition, the ratio of the thickness of the fixing layer on the other side to the thickness of the base layer is preferably within the above range. In addition, the ratio of the thickness of the fixing layer on one side to the thickness of the base layer and the ratio of the thickness of the fixing layer on the other side to the thickness of the base layer may be the same or different.

[0043] Next, the tape-shaped yarn B of the woven fabric of the present invention will be described. This tape-shaped yarn B has a light reflectance of 30% or more. Here, if the light reflectance is high, the light absorption rate becomes relatively low, and when the tape-shaped yarn B is exposed to solar radiation, an increase in its own temperature can be suppressed. It is more preferably 35% or more, and even more preferably 40% or more. Methods for achieving a light reflectance of 30% or more include a method of adding an infrared scattering agent to the tape-shaped yarn B and a method of generating micropores in the tape-shaped yarn B.

[0044] Examples of the infrared scattering agent include titanium oxide, zinc oxide, calcium carbonate, and barium sulfate. Among these, titanium oxide is preferred because it has a large difference in refractive index from the thermoplastic resin.

[0045] The number average particle size of the infrared scattering agent is preferably 500 to 2500 nm. The infrared scattering agent utilizes a phenomenon called Mie scattering, and can most efficiently scatter light rays with a wavelength twice the particle size. In general, titanium oxide and zinc oxide have a particle size distribution when industrially produced. If the average particle size is 500 nm or more, it is possible to reduce the scattering of visible light by particles smaller than the average particle size, which exists with a certain probability due to the particle size distribution. The number average particle size of the infrared scattering agent is more preferably 600 nm or more, and even more preferably 700 nm or more. In addition, as the number average particle size becomes smaller, the number of interfaces between the thermoplastic resin and the infrared scattering agent per mass of the infrared scattering agent increases. Since Mie scattering occurs at the interface between materials with different refractive indexes, if the number of interfaces between the thermoplastic resin and the infrared scattering agent increases, a sufficient effect can be obtained even with a small amount of the infrared scattering agent added, so the number average particle size of the infrared scattering agent is 2500 nm or less. From the above viewpoint, it is preferably 2000 nm or less, and more preferably 1800 nm or less.

[0046] From the above viewpoints, it is particularly preferable that the tape-shaped yarn B contains titanium oxide having a number average particle size of 500 to 2500 nm.

[0047] To generate micropores in the tape-like yarn B, a known method such as uniaxial or biaxial stretching of a thermoplastic resin containing a nucleating agent such as barium sulfate or calcium carbonate can be used.

[0048] The width, thickness, preferred state when uniaxially stretched, layer structure, and material of each layer of the tape-shaped yarn B are the same as those of the tape-shaped yarn A.

[0049] The tape-shaped yarn B may be white in color because the infrared scattering agent contained therein also scatters visible light. Being white means that it does not have a specific absorption range in the wavelength range of visible light, which is preferable from the viewpoint that the sunshade sheet itself is less likely to become hot.

[0050] At least one surface of the tape-like yarn B may have a color other than white and yellow. As described in Non-Patent Document 1 (J. Jpn. Soc. Colour Mater., 89(6), 191-196 (2016)), it is known that white and yellow colors strongly attract phytophagous insects. From the viewpoint of being able to suppress the attraction of phytophagous insects, it is preferable that at least one surface of the tape-like yarn B has a color other than white and yellow. From the viewpoint of being able to further suppress the attraction of phytophagous insects, it is more preferable that both surfaces of the tape-like yarn B have a color other than white and yellow.

[0051] In the present invention, the color of the tape-shaped yarn B being white means that the color of the tape-shaped yarn B satisfies the following condition (A) in the CIE1976 L*a*b* color space described in condition C of JIS Z8722:2013, which can be calculated from the reflectance spectrum of the tape-shaped yarn B:

[0052] (A)L*>85 In the present invention, the color of the tape-shaped yarn B being yellow means that in the CIE1976 L*a*b* color space described in condition C of JIS Z8722:2013, which can be calculated from the reflectance spectrum of the tape-shaped yarn B, all of the following conditions (B), (C), and (D) are satisfied: (B) L*>50 (C)-15 <a*<10 (D)b*>10 In other words, in the present invention, when at least one surface of the tape-like yarn B has a color that is neither white nor yellow, this means that neither of the conditions that the tape-like yarn B is white in color nor the condition that the deep yarn B is yellow in color is satisfied.

[0053] Examples of methods for making the tape-shaped yarn B a color other than white or yellow include a method of adding a colorant in addition to the infrared scattering agent, and a method of painting or printing the surface of the tape-shaped yarn. From the viewpoints of weather resistance and productivity, the method of adding a colorant is preferred.

[0054] The colorant may be either a dye or a pigment, but is preferably a pigment, which has excellent weather resistance. The pigment may be either an inorganic pigment or an organic pigment. Examples of inorganic pigments include red lead, iron oxide red, ultramarine blue, and carbon flake, while examples of organic pigments include diketopyrrolopyrrole, perylene, quinacridone, dioxazine, and phthalocyanine.

[0055] The content of the colorant in the tape-shaped yarn B may be any amount within a range in which the average reflectance of the tape-shaped yarn B at wavelengths of 781 to 2500 nm is not less than 30%. The content of the colorant in the entire tape-shaped yarn B is preferably 20 mass % or less, from the viewpoint that the mechanical strength of the tape-shaped yarn B can be easily obtained.

[0056] Next, the yarn C contained in the woven fabric of the present invention will be described.

[0057] This yarn C contains a thermoplastic resin as a main component. Here, containing as a main component means that the thermoplastic resin is contained in an amount of more than 50 mass% of the entire monofilament. Specifically, this thermoplastic resin may be any thermoplastic resin such as polyolefin, polyester, methacrylic acid ester, polycarbonate, or a mixture thereof. From the viewpoints of productivity and weather resistance, polyethylene, polypropylene, and polyethylene terephthalate are preferred.

[0058] Yarn C satisfies at least one of the following conditions (A) and (B). (A) The ratio C of the area of ​​the portion of the yarn C overlapping with the tape-shaped yarn A to the area of ​​the woven fabric is 0.182 or less. (B) The visible light transmittance of yarn C is 70% or more. First, in the condition (A), the ratio C of the area of ​​the portion of the yarn C overlapping the tape-shaped yarn A to the woven fabric area is set to 0.182 or less. This will be described in detail below.

[0059] In the present invention, there are three possible states for yarn C: a first state in which tape-like yarn A and yarn C overlap; a second state in which tape-like yarn B and yarn C overlap; and a third state in which yarn C is exposed without overlapping either tape-like yarn A or tape-like yarn B. Here, the woven fabric of the present invention must be excellent in both wavelength selective transmission performance and light reflectance performance. Wavelength selective transmission performance is achieved by tape-like yarn A, which contains an infrared absorbing agent, selectively transmitting visible light and selectively absorbing infrared light, so the first state is the most important of the three above. The area of ​​the portion in the first state in which tape-like yarn A and yarn C overlap is: (A) be small enough to maintain the excellent wavelength selective transmission performance and excellent light reflectance performance of the fabric of the present invention; or, (B) The visible light transmittance of the portion in the first state is 70% or more. is required.

[0060] That is, in the present invention, the above-mentioned ratio C is the ratio of the total area of ​​the portions in the first state where the tape-shaped yarn A and the yarn C overlap to the area of ​​the woven fabric.

[0061] Since the light reflectance of the tape-shaped yarn B is 30% or more, the tape-shaped yarn B has poor wavelength selective transmission function. Therefore, regardless of the visible light transmittance of the yarn C, the portion in the second state where the tape-shaped yarn B and the yarn C overlap has poor wavelength selective transmission function.

[0062] The exposed yarn C that does not overlap either the tape-like yarn A or the tape-like yarn B, i.e., the portion in the third state, is second in importance after the portion in the first state because it may be possible for visible light to enter the inside of the house through that portion. If the ratio of the area of ​​the portion in the third state to the area of ​​the woven fabric is 0.182 or less, the effect of the portion in the third state on the entire woven fabric will be limited regardless of the level of the visible light transmittance of yarn C.

[0063] Next, a case where yarn C satisfies condition (A) will be described. When the woven fabric is viewed perpendicularly to the surface direction of the woven fabric, the area where tape-like yarn A or tape-like yarn B overlaps with yarn C is limited, so that the decrease in visible light transmittance of the woven fabric can be limited regardless of the visible light transmittance of yarn C. If the ratio C of the area of ​​the portion of yarn C overlapping with tape-like yarn A to the woven fabric area is 0.002 or more, this is preferable because the tensile strength in the direction parallel to yarn C can be increased. It is more preferable that it is 0.006 or more, and even more preferable that it is 0.012 or more.

[0064] Next, a case where condition (B) is satisfied will be described. A decrease in visible light transmittance is suppressed in the area where the tape-shaped yarn A and the yarn C overlap. The higher the visible light transmittance of the yarn C, the better, but since the difference in refractive index between the thermoplastic resin and air causes surface reflection, the transmittance is 92% or less.

[0065] As described above, in the woven fabric of the present invention, the yarn C satisfies at least one of the conditions (A) and (B). Next, a preferred embodiment that the yarn C can take when the yarn C satisfies at least one of the conditions (A) and (B) will be described. The yarn C may be a monofilament or a tape-like yarn. In general, the surface area per unit mass of a monofilament is smaller than that of a tape-like yarn, so it is preferable that the yarn C be a monofilament from the viewpoint that deterioration progressing from the surface is less likely to occur.

[0066] When the yarn C is a monofilament, its diameter is preferably 0.1 to 0.6 mm. By making the diameter 0.1 mm or more, the tensile strength in the direction parallel to the yarn C can be increased, and the thickness (diameter) of the yarn C can be used to generate three-dimensional gaps and surface irregularities in the woven fabric. The three-dimensional gaps in the woven fabric can be expected to provide a passage for air heated by sunlight to cool the house and to discharge moisture when condensation occurs due to environmental changes. In addition, the unevenness of the woven fabric can limit the contact area between the house ceiling or wall surface and the woven fabric when covering the house, which is preferable because it can suppress adhesion due to dirt. By making the diameter of the yarn C 0.6 mm or less, the stiffness (bending resistance) of the yarn C can be limited, making it easy to fold the woven fabric. In addition, it is preferable that the yarn C has a core-sheath structure with the fixing layer as the sheath and the base material layer as the core, since this makes the fixation of the intersections of the tape-like yarn A and the tape-like yarn B with the yarn C stronger and suppresses the occurrence of floating and voids. If there are floating or voids, an air layer will exist for the light passing through the fabric in a substantially perpendicular direction, and the reflection occurring at the interface may reduce the wavelength selective transmission function of the fabric. The fixing layer is a layer that has the function of fixing the contact parts (intersections) of the tape-like yarn A and the tape-like yarn B with the yarn C, and the fixing layer can be made of low-melting thermoplastic resins such as low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE), various adhesives such as acrylic, silicone, and epoxy, and various pressure-sensitive adhesives such as acrylic, silicone, urethane, and rubber. Among these, it is more preferable to use low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), or a mixture of these for the fixing layer of the monofilament, which is fixed by heat fusion, from the viewpoints of enabling one-pass production by co-extrusion, and being easy to handle because it has no tackiness at room temperature.

[0067] The base layer is a layer having the function of providing mechanical strength to the yarn C, and examples of the material that can be used for this layer include high density polyethylene, polypropylene, and polyvinyl chloride.

[0068] When the yarn C has a core-sheath structure with the fixing layer as the sheath and the base material layer as the core, the cross-sectional area ratio obtained by dividing the cross-sectional area of ​​the fixing layer in the cross section of the yarn C by the cross-sectional area of ​​the base material layer is preferably 0.01 to 0.50, more preferably 0.05 to 0.25. When this ratio is 0.01 or more, the tape-shaped yarn A or tape-shaped yarn B and the yarn C are firmly fixed, and floating and voids can be reduced. When this ratio is 0.5 or less, the content of the base material layer in the yarn C is relatively large, and since this base material layer is rigid, the tensile strength in the direction parallel to the longitudinal direction of the yarn C is increased, and as a result, the strength of the woven fabric of the present invention is improved. The cross-sectional shape of the yarn C is not particularly limited, such as a circle, an ellipse, a rectangle, a star, or a Y-shape, but a circle is preferable because it is easy to manufacture and maintain the spindle.

[0069] The fabric of the present invention can be woven by any known method such as plain weave, twill weave, satin weave, leno weave, etc. From the viewpoint of resistance to friction, it is preferable to use the plain weave method.

[0070] The woven fabric of the present invention may also have a form that further includes a yarn (hereinafter referred to as yarn D) that is a monofilament having a diameter of 0.6 mm or less, unlike both tape-shaped yarn A and tape-shaped yarn B. In this form of woven fabric, when tape-shaped yarn A and tape-shaped yarn B are warp yarns, yarn D is also a warp yarn, and when tape-shaped yarn A and tape-shaped yarn B are weft yarns, yarn D is also a weft yarn. When a woven fabric is produced using tape-shaped yarn A that has not been uniaxially stretched or tape-shaped yarn A having a thin thickness, tape-shaped yarn B that has not been uniaxially stretched or tape-shaped yarn B having a thin thickness, there is an advantage that a general-purpose extruder can be used, but the tensile strength in a direction parallel to tape-shaped yarn A and tape-shaped yarn B may be insufficient. Therefore, by using yarn D, which has excellent mechanical strength, as the warp when tape-like yarn A and tape-like yarn B are the warp, or as the weft when tape-like yarn A and tape-like yarn B are the weft, the tensile strength of the woven fabric in the direction parallel to tape-like yarn A and tape-like yarn B can be increased. Furthermore, when tape-like yarn A or tape-like yarn B is not fixed to yarn C by heat fusion, adhesive, pressure-sensitive adhesive, or the like, or when tape-like yarn A or tape-like yarn B is not fixed to yarn C by weak strength, the inclusion of yarn D in the woven fabric increases the number of intersections between the warp and weft of the woven fabric compared to the case where the woven fabric does not include yarn D, and therefore it is preferable to suppress the phenomenon in which the intersections of the warp and weft are misaligned on the plane of the woven fabric, which is called "weave misalignment." When the weave misalignment occurs in the woven fabric, the openings where no yarns are present may become large in some places, and the openings may catch on protruding objects such as pipes and metal fixtures of agricultural greenhouses, making the woven fabric more likely to tear. From the viewpoint of excellent mechanical strength and weather resistance, yarn D is preferably composed of one or more materials selected from the group consisting of high-density polyethylene, polypropylene, and polyvinyl chloride. Yarn D may be the same yarn as yarn C, so long as it satisfies the above characteristics. 2 shows a schematic diagram of another example of the fabric according to the present invention, that is, a fabric having yarn D. In the above-mentioned fabric 1, tape-like yarn A (indicated by reference number 2), tape-like yarn (indicated by reference number 3) and yarn D (indicated by reference number 5) are warp yarns, and yarn C (indicated by reference number 4) is a weft yarn.

[0071] The woven fabric of the present invention may be provided with functions such as anti-fog agent, antifouling agent, repellent, insect repellent, antibacterial agent, etc., by post-processing, within the range that does not impair the effects of the present invention. Examples of the method for providing the functions include a dip-nip method and a spray method.

[0072] When the woven fabric of the present invention is expected to be used in an environment exposed to sunlight, such as outdoors as an agricultural sheet, it is preferable to impart the function of an ultraviolet absorbing agent or a light stabilizer to improve weather resistance. Examples of the ultraviolet absorbing agent include triazine derivatives and benzotriazole derivatives. Examples of the light stabilizer include hindered amine derivatives. The ultraviolet shielding agent or the light stabilizer may be added to the film by blending it into the film or by post-processing.

[0073] The woven fabric of the present invention is also suitable for use as a sunshade sheet, awning, shade, interior curtain, and blind. Here, these may contain sheet-like materials other than the woven fabric of the present invention, as long as the effect of the woven fabric of the present invention is not impaired. Specifically, when the woven fabric of the present invention is applied to an object to be applied, such as an agricultural house, in the case where the width or length of the woven fabric is insufficient, the woven fabric may be integrated with a sheet-like material other than the above-mentioned woven fabric by sewing. When the woven fabric of the present invention is used as a sunshade sheet, the woven fabric can be joined together by a known method such as sewing, heat fusion, or ultrasonic fusion according to the required size. In addition, by applying eyelet processing to the outer periphery of the woven fabric, it becomes possible to fix it with a rope when it is stretched and fixed to the agricultural pipe house.

[0074] The above-mentioned sunshade sheet may be draped over an agricultural pipe house covered with an agricultural vinyl film or an agricultural PO film, or may be stretched directly over the pillars of the pipe house. When draped over a film, there are advantages in that the amount of moisture given to crops is easily controlled because rain does not fall on the crops, and the sunshade sheet can be easily removed when more light is required temporarily on cloudy days, etc. When stretched directly over the pillars of a pipe house, there is an advantage in that the woven fabric of the present invention is breathable, so that ventilation of air heated by sunlight is promoted, making it difficult for the temperature inside the house to rise. EXAMPLES

[0075] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these. The performances in the examples were measured by the following methods.

[0076] [Measurement method] (1) Visible light transmittance, infrared transmittance, and light reflectance of yarn The visible light transmittance, infrared transmittance, and light reflectance of the tape-shaped yarn A, tape-shaped yarn B, and yarn C were measured by the following method. Five yarn test pieces including parts where the yarns do not intersect were randomly taken from the woven fabric. Using a microscopic ultraviolet-visible-near infrared spectrophotometer "MSV-5200DGK (manufactured by JASCO Corporation)", the transmittance and reflectance of light in the wavelength range of 300 to 2500 nm were measured on one side and the other side of the test piece for the parts where the yarns do not intersect. The average value of the transmittance of the 10 light beams in the wavelength range of 380 to 780 nm obtained on one side and the other side was taken as the visible light transmittance (%), the average value of the transmittance of the light beams in the wavelength range of 781 to 2500 nm was taken as the infrared transmittance (%), and the average value of the reflectance of the light beams in the wavelength range of 380 to 2500 nm was taken as the light reflectance. The measurement aperture diameter was 100 μm, and the sampling interval was 1 nm.

[0077] (2) Visible light transmittance, infrared transmittance, solar absorptance, and solar heat gain coefficient of textiles Ten test pieces measuring 30 mm x 30 mm were randomly taken from the fabric. Using a UV-3600plus ultraviolet / visible / near-infrared spectrophotometer (Shimadzu Corporation), the test pieces were set in the sample holder at randomly selected angles, and the transmittance and reflectance of light in the wavelength range of 300 to 2500 nm were measured at 1 nm intervals on one side and the other side of the test piece. The average value of the transmittance of 20 light rays in the wavelength range of 380 to 780 nm on one side and the other side was taken as the visible light transmittance (%), and the average value of the transmittance of the arc in the wavelength range of 781 to 2500 nm was taken as the infrared transmittance (%) of the fabric. The measurement aperture size was 15 mm x 3 mm.

[0078] The solar absorptance of the fabric was calculated using the transmittance and reflectance of light in the wavelength range of 300 to 2500 nm measured by the method described above, following the method for one glass plate, Example 1 of 9 Calculation method for solar heat gain coefficient, on page 11 of JIS R3106 (2019), replacing the glass plate with a test piece. However, the ratio N1 of the heat flow absorbed by the test piece and transmitted to the room to the incident solar radiation was calculated as 1 / 3.

[0079] (3) The proportion A of the woven fabric area occupied by tape-shaped yarn A, and the proportion B of the woven fabric area occupied by tape-shaped yarn B Five test pieces measuring 100 mm x 100 mm were randomly taken from the woven fabric. Using a JIS Class 1 metal ruler, the area of ​​the tape-like yarn A on one side of the above-mentioned woven fabric test piece was measured, and the total area of ​​the taken test pieces (50,000 mm) was calculated. 2 ) to determine the proportion A of the tape-like yarn A in the woven fabric.

[0080] Five test pieces measuring 100 mm x 100 mm were randomly taken from the fabric. Using a JIS Class 1 metal ruler, the total area of ​​the fabric in which the tape-like yarn A was present was measured from a direction perpendicular to the surface direction of the fabric. The total area of ​​the fabric (50,000 mm 2 ) to measure the area A occupied by the tape-like yarn A in the woven fabric.

[0081] The proportion B of the tape-like yarn B in the woven fabric area was also measured in the same manner as in the measurement of the proportion A of the tape-like yarn A in the woven fabric area described above.

[0082] (4) The ratio C of the overlapping area of ​​yarn C and tape-like yarn A to the total fabric area Five test pieces measuring 100 mm x 100 mm were randomly taken from the woven fabric. The woven fabric was observed with a Keyence Corporation microscope VHX8000 at an objective lens magnification of 25x from a direction perpendicular to the plane of the woven fabric. The area measurement function of the attached software was used to determine the overlapping area of ​​yarn C and tape-like yarn A, and the total area of ​​the woven fabric (50,000 mm 2 ) to calculate the percentage C of the overlapping area of ​​yarn C and tape-like yarn A in the woven fabric area.

[0083] (5) Number average particle size of infrared scattering agent Tape-shaped yarn B was taken from the woven fabric and cut by ion milling. The cross section of tape-shaped yarn B was observed at 20,000 times magnification with a transmission electron microscope (TEM), and the particle size of the infrared scattering agent was determined using a scale bar. The particles contained in tape-shaped yarn B were subjected to qualitative analysis by energy dispersive X-ray spectroscopy to identify the material of the particles. Next, particles corresponding to the infrared scattering agent were identified from the identified material of the particles. The particle size of a total of 20 infrared scattering agents randomly selected from the particles corresponding to the infrared scattering agent was measured, and the average particle size was determined by the arithmetic average. In addition, when the cross section of the infrared scattering agent is not spherical, the TEM image of the cross section of the infrared scattering agent was surrounded by a rectangle with the longest side, and the arithmetic average value of the long side and the short side was taken as the particle size of the infrared scattering agent.

[0084] (6) Breathability of fabric Five test pieces measuring 100 mm x 100 mm were randomly taken from the fabric and measured using JIS L1096 (2010) Method A (Fragile method). One side and the other side of the test piece were measured, and the arithmetic average of the ten measurements was taken as the air permeability of the fabric.

[0085] (7) Color of tape-like yarn B (L*a*b* space color) The L*a*b* spatial color of tape-shaped yarn B was measured by randomly collecting five test pieces of yarn B, including areas where the yarns did not intersect, from the woven fabric. Using a spectrophotometer "CM-2600d (Konica Minolta, Inc.)," ​​the areas where the yarns did not intersect on one side and the other side of the test piece were measured using the method described in JIS Z8722 condition C. The conditions were SCI (specular reflection included) and a 10° viewing angle.

[0086] [Example 1] (Tape-shaped yarn A) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and powder in which cesium tungsten oxide was dispersed as an infrared absorber (YMDS-874 manufactured by Sumitomo Metal Mining Co., Ltd., purity 23%) were mixed in a ratio of 75:25 and then chipped to produce a master chip.

[0087] In a three-layered coextrusion, the master chip was diluted with a high-density polyethylene resin chip (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) to form a substrate layer so that the content of the cesium tungsten oxide in the substrate layer was 3.6% by mass, and a film was produced in which low-density polyethylene (Sumikasen F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the substrate layer. At this time, the thickness ratio of the anchoring layer / substrate layer / anchoring layer was 1 / 8 / 1.

[0088] Thereafter, the film was slit to a predetermined width to obtain tape-shaped yarn A having a width of 3 mm and a thickness (total thickness of anchoring layer / base layer / anchoring layer) of 40 μm.

[0089] (Tape-shaped yarn B) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and titanium oxide (PFR404 manufactured by Ishihara Sangyo Kaisha, Ltd.) as an infrared scattering agent were mixed in a ratio of 70:30, and then chipped to prepare a master chip.

[0090] In a three-layered coextrusion process, the master chips were diluted with high-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) to form a substrate layer so that the content of titanium oxide in the substrate layer was 22.5% by mass, and a film was produced in which low-density polyethylene (Sumikathen F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the substrate layer. At this time, the thickness ratio of the anchoring layer / substrate layer / anchoring layer was 1 / 8 / 1.

[0091] Thereafter, the film was slit to a predetermined width to obtain tape-shaped yarn B having a width of 3 mm and a thickness (total thickness of anchoring layer / base layer / anchoring layer) of 40 μm.

[0092] (Yarn C) In a spinning machine having a concentric core-sheath die, a high-density polyethylene resin (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) was used as the core, i.e., base layer, and a low-density polyethylene resin (Sumikasen F200 manufactured by Sumitomo Chemical Co., Ltd.) was used as the sheath, i.e., fixing layer, and the spinning conditions were an extrusion temperature of 190°C, a drawing water tank temperature of 100°C, a heat setting temperature of 120°C, and a draw ratio of 10 times to obtain Yarn C, a monofilament having a core-sheath structure. The extrusion amount was adjusted so that the diameter of the monofilament was 0.29 mm, and the area ratio of the core in the cross section when cut perpendicular to the longitudinal direction was 80%, and the area ratio of the sheath was 20%.

[0093] (fabric) Using a rapier loom, two tape-like yarns A obtained by the above method were arranged as warp yarns, followed by one tape-like yarn B obtained by the above method, in that order, and plain woven so that the tape-like yarns A or tape-like yarn B were spaced at 8.0 yarns / inch, and the weft yarn C obtained by the above method was spaced at 8.0 yarns / inch. Further, only one side of the fabric was brought into contact with a heated roll having a surface temperature of 125°C, thereby fixing the intersections of the tape-like yarns and the monofilaments by thermal fusion, and the woven fabric of Example 1 was obtained.

[0094] The structures and physical properties of the obtained tape-shaped yarn A, tape-shaped yarn B, yarn C and woven fabric are shown in Table 1.

[0095] [Example 2] (Tape-shaped yarn A) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and powder in which cesium tungsten oxide was dispersed as an infrared absorber (YMDS-874 manufactured by Sumitomo Metal Mining Co., Ltd., purity 23%) were mixed in a ratio of 75:25 and then chipped to produce a master chip.

[0096] In a single layer extrusion, the master chips were diluted with high density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) so that the content of the cesium tungsten oxide in the base layer was 1.7% by mass, to produce a film.

[0097] Thereafter, the film was slit to obtain tape-shaped yarn A having a width of 5.8 mm and a thickness of 100 μm.

[0098] (Tape-shaped yarn B) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and titanium oxide (PFR404 manufactured by Ishihara Sangyo Kaisha, Ltd.) as an infrared scattering agent were mixed in a ratio of 70:30, and then chipped to prepare a master chip.

[0099] In a single layer extrusion, the master chips were diluted with high density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) so that the content of the titanium oxide in the base layer was 7.2% by mass, to produce a film.

[0100] Thereafter, the film was slit to obtain tape-shaped yarn A having a width of 5.8 mm and a thickness of 100 μm.

[0101] (Yarn C) A single-layer monofilament, Yarn C, was obtained using a spinning machine with a circular die and high-density polyethylene resin (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) under spinning conditions of an extrusion temperature of 190°C, a drawing water tank temperature of 100°C, a heat setting temperature of 120°C, and a draw ratio of 10. The extrusion amount was adjusted so that the monofilament had a diameter of 0.25 mm.

[0102] (Yarn D) Yarn D was obtained in the same manner as Yarn C.

[0103] (fabric) Using a rapier loom, the tape-like yarn A obtained by the above method, three strands of yarn D obtained by the above method, the tape-like yarn A, three strands of yarn D, the tape-like yarn B obtained by the above method, and three strands of yarn D were arranged repeatedly in this order as warp yarns, and plain weaving was performed so that the tape-like yarn A or tape-like yarn B was spaced at 3.4 strands / inch, and the weft yarn C obtained by the above method was spaced at 13 strands / inch.

[0104] The structures and physical properties of the obtained tape-shaped yarn A, tape-shaped yarn B, yarn C and woven fabric are shown in Table 1.

[0105] [Example 3] (Tape-shaped yarn B) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and titanium oxide (R-390 manufactured by Ishihara Sangyo Kaisha, Ltd.) were mixed in a ratio of 70:30, and then chipped to prepare a master chip.

[0106] In the tape-like yarn B manufacturing process, the master chips were diluted with high-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) to form a substrate layer by co-extrusion of three layers so that the content of titanium oxide in the substrate layer was 15.2% by mass, and a film was produced in which low-density polyethylene (Sumikathene F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the substrate layer. At this time, the thickness ratio of anchoring layer / substrate layer / anchoring layer was 1 / 8 / 1.

[0107] The woven fabric of Example 3 was obtained in the same manner as in Example 1, except that the tape-shaped yarn B was changed.

[0108] The structures and physical properties of the obtained tape-shaped yarn A, tape-shaped yarn B, yarn C and woven fabric are shown in Table 1.

[0109] [Example 4] (Tape-shaped yarn A) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and powder in which cesium tungsten oxide was dispersed as an infrared absorber (YMDS-874 manufactured by Sumitomo Metal Mining Co., Ltd., purity 23%) were mixed in a ratio of 75:25 and then chipped to produce a master chip.

[0110] In a three-layered coextrusion, the master chip was diluted with a high-density polyethylene resin chip (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) to form a substrate layer so that the content of the cesium tungsten oxide in the substrate layer was 6.1% by mass, and a film was produced in which low-density polyethylene (Sumikathene F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the substrate layer. At this time, the thickness ratio of the anchoring layer / substrate layer / anchoring layer was 1 / 8 / 1.

[0111] Thereafter, the film was slit to a predetermined width to obtain tape-shaped yarn A having a width of 3 mm and a thickness (total thickness of anchoring layer / base layer / anchoring layer) of 40 μm.

[0112] (Tape-shaped yarn B) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and titanium oxide (PFR404 manufactured by Ishihara Sangyo Kaisha, Ltd.) as an infrared scattering agent were mixed in a ratio of 70:30, and then chipped to prepare a master chip.

[0113] In a three-layered coextrusion, the master chips were diluted with high-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) to form a substrate layer so that the content of titanium oxide in the substrate layer was 9.8% by mass, and a film was produced in which low-density polyethylene (Sumikathen F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the substrate layer. At this time, the thickness ratio of the anchoring layer / substrate layer / anchoring layer was 1 / 8 / 1.

[0114] Thereafter, the film was slit to a predetermined width to obtain tape-shaped yarn B having a width of 3 mm and a thickness (total thickness of anchoring layer / base layer / anchoring layer) of 40 μm.

[0115] (fabric) Using a rapier loom, one tape-like yarn A obtained by the method described in Example 1 was used as the warp yarn, followed by one tape-like yarn B obtained by the method described in Example 1, in that order, and plain weaving was performed so that the tape-like yarn A or tape-like yarn B was spaced at 8.0 yarns / inch, and the weft yarn C obtained by the method described in Example 1 was spaced at 8.0 yarns / inch.

[0116] The woven fabric of Example 4 was obtained in the same manner as in Example 1, except that the cesium tungsten oxide content of tape-shaped yarn A, the titanium oxide content of tape-shaped yarn B, and the ratio of tape-shaped yarn A to tape-shaped yarn B were changed (the value of ratio A / ratio B was set to 1.0).

[0117] The structures and physical properties of the obtained tape-shaped yarn A, tape-shaped yarn B, yarn C and woven fabric are shown in Table 1.

[0118] [Example 5] (Tape-shaped yarn B) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and titanium oxide (PFR404 manufactured by Ishihara Sangyo Kaisha, Ltd.) as an infrared scattering agent were mixed in a ratio of 70:30, and then chipped to prepare a master chip.

[0119] In the three-layer coextrusion, the master chips were diluted with high-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) so that the content of the titanium oxide in the base layer was 22.5% by mass, and 0.25% by mass of a colorant master batch (PEX3184BLUE#021 manufactured by Tokyo Ink Co., Ltd.) was added as a colorant to form the base layer, and a film was produced in which low-density polyethylene (Sumikathene F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the base layer. At this time, the thickness ratio of the anchoring layer / base layer / anchoring layer was 1 / 8 / 1.

[0120] Thereafter, the film was slit to a predetermined width to obtain tape-shaped yarn B having a width of 3 mm and a thickness (total thickness of anchoring layer / base layer / anchoring layer) of 40 μm.

[0121] A woven fabric of Example 5 was obtained in the same manner as in Example 1, except for using tape-shaped yarn B.

[0122] [Example 6] (Tape-shaped yarn B) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and titanium oxide (PFR404 manufactured by Ishihara Sangyo Kaisha, Ltd.) as an infrared scattering agent were mixed in a ratio of 70:30, and then chipped to prepare a master chip.

[0123] In the three-layer coextrusion, the master chips were diluted with high-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) so that the content of the titanium oxide in the base layer was 22.5% by mass, and 0.13% by mass of a colorant master batch (PEX3025RED#175 manufactured by Tokyo Ink Co., Ltd.) was added as a colorant to form the base layer, and a film was produced in which low-density polyethylene (Sumikathene F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the base layer. At this time, the thickness ratio of the anchoring layer / base layer / anchoring layer was 1 / 8 / 1.

[0124] Thereafter, the film was slit to a predetermined width to obtain tape-shaped yarn B having a width of 3 mm and a thickness (total thickness of anchoring layer / base layer / anchoring layer) of 40 μm.

[0125] A woven fabric of Example 6 was obtained in the same manner as in Example 1, except for using tape-shaped yarn B.

[0126] [Comparative Example 1] (Tape-shaped yarn A) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and powder in which cesium tungsten oxide was dispersed as an infrared absorber (YMDS-874 manufactured by Sumitomo Metal Mining Co., Ltd., purity 23%) were mixed in a ratio of 75:25 and then chipped to produce a master chip.

[0127] In a three-layered coextrusion, the master chip was diluted with a high-density polyethylene resin chip (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) to form a substrate layer so that the content of the cesium tungsten oxide in the substrate layer was 4.9% by mass, and a film was produced in which low-density polyethylene (Sumikasen F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the substrate layer. At this time, the thickness ratio of the anchoring layer / substrate layer / anchoring layer was 1 / 8 / 1.

[0128] Thereafter, the film was slit to a predetermined width to obtain tape-shaped yarn A having a width of 3 mm and a thickness (total thickness of anchoring layer / base layer / anchoring layer) of 40 μm.

[0129] (Yarn C) In a spinning machine having a concentric core-sheath die, a high-density polyethylene resin (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) was used as the core, i.e., base layer, and a low-density polyethylene resin (Sumikasen F200 manufactured by Sumitomo Chemical Co., Ltd.) was used as the sheath, i.e., fixing layer, and the spinning conditions were an extrusion temperature of 190°C, a drawing water tank temperature of 100°C, a heat setting temperature of 120°C, and a draw ratio of 10 times to obtain Yarn C, a monofilament having a core-sheath structure. The extrusion amount was adjusted so that the diameter of the monofilament was 0.29 mm, and the area ratio of the core in the cross section when cut perpendicular to the longitudinal direction was 80%, and the area ratio of the sheath was 20%.

[0130] (fabric) Using a rapier loom, the tape-like yarn A obtained by the above method was used as the warp yarn at a spacing of 8.0 yarns / inch, and the yarn C obtained by the above method was used as the weft yarn at a spacing of 8.0 yarns / inch. The fabric was then plain woven, and only one side of the fabric was brought into contact with a heated roll with a surface temperature of 125°C, thereby fixing the intersections of the tape-like yarn and the monofilament by thermal fusion, thereby obtaining the woven fabric of Comparative Example 1.

[0131] The structures and physical properties of the obtained tape-shaped yarn A, tape-shaped yarn B, yarn C and woven fabric are shown in Table 1.

[0132] [Comparative Example 2] (Tape-shaped yarn B) High-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) and titanium oxide (PFR404 manufactured by Ishihara Sangyo Kaisha, Ltd.) as an infrared scattering agent were mixed in a ratio of 70:30, and then chipped to prepare a master chip.

[0133] In a three-layered coextrusion, the master chips were diluted with high-density polyethylene resin chips (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) to form a substrate layer so that the content of titanium oxide in the substrate layer was 8.9% by mass, and a film was produced in which low-density polyethylene (Sumikathen F200 manufactured by Sumitomo Chemical Co., Ltd.) was arranged as an anchoring layer on both sides of the substrate layer. At this time, the thickness ratio of the anchoring layer / substrate layer / anchoring layer was 1 / 8 / 1.

[0134] The film was then slit to a specified width, stretched 7 times on a 110°C hot plate, and heat-fixed at 120°C to obtain tape-shaped yarn B with a width of 3 mm and a thickness (total thickness of fixing layer / base layer / fixing layer) of 40 μm.

[0135] (Yarn C) In a spinning machine having a concentric core-sheath die, a high-density polyethylene resin (E8040 manufactured by Keiyo Polyethylene Co., Ltd.) was used as the core, i.e., base layer, and a low-density polyethylene resin (Sumikasen F200 manufactured by Sumitomo Chemical Co., Ltd.) was used as the sheath, i.e., fixing layer, and the spinning conditions were an extrusion temperature of 190°C, a drawing water tank temperature of 100°C, a heat setting temperature of 120°C, and a draw ratio of 10 times to obtain Yarn C, a monofilament having a core-sheath structure. The extrusion amount was adjusted so that the diameter of the monofilament was 0.29 mm, and the area ratio of the core in the cross section when cut perpendicular to the longitudinal direction was 80%, and the area ratio of the sheath was 20%.

[0136] (fabric) Using a rapier loom, the tape-like yarn B obtained by the above method was used as the warp yarn at a spacing of 8.0 yarns / inch, and the yarn C obtained by the above method was used as the weft yarn at a spacing of 8.0 yarns / inch. The fabric was then plain woven, and only one side of the fabric was brought into contact with a heated roll having a surface temperature of 125°C, thereby fixing the intersections of the tape-like yarn and the monofilament by thermal fusion, thereby obtaining the woven fabric of Comparative Example 1.

[0137] The structures and physical properties of the obtained tape-shaped yarn A, tape-shaped yarn B, yarn C and woven fabric are shown in Table 1.

[0138] Comparing Example 1 with Comparative Example 1, which is composed only of tape-shaped yarn A without using tape-shaped yarn B, the solar heat acquisition coefficient is almost the same, but the solar absorption rate of Example 1 is smaller, indicating that the woven fabric is less likely to become hot even when exposed to direct sunlight.

[0139] When comparing Example 1 with Comparative Example 2, which does not use tape-shaped yarn A and is composed only of tape-shaped yarn B, it can be seen that the solar heat gain coefficients are almost the same, but Example 1 has a superior visible light transmittance.

[0140] Comparing Example 1 with Example 3, in which titanium oxide with a small number average particle size was used as the infrared scattering agent in tape-shaped yarn B, Example 1 has a lower infrared transmittance and a higher light reflectance for tape-shaped yarn B. As a result, it is found that while the solar heat gain coefficients are roughly the same, Example 1 has a superior visible light transmittance.

[0141] [Table 1] [Industrial Applicability]

[0142] The woven fabric of the present invention is preferably used for agricultural sunshade sheets, awnings, shades, interior curtains and blinds, etc. [Explanation of symbols]

[0143] 1 textile 2 Tape-shaped yarn A 3. Tape-shaped yarn B 4 Yarn C 5 Yarn D

Claims

1. The main component is thermoplastic resin. The value obtained by subtracting the infrared transmittance from the visible light transmittance is 35% or more, and A tape-shaped yarn A having a light reflectance of 20% or less; The main component is thermoplastic resin. A tape-shaped yarn B having a light reflectance of 30% or more; It is composed of yarn C mainly composed of thermoplastic resin, The yarn C constitutes one of the warp yarn and the weft yarn, The tape-shaped yarn A and the tape-shaped yarn B together constitute the other of the warp and weft yarns. The ratio (proportion A / proportion B) of the proportion A of the tape-like yarn A in the woven fabric area to the proportion B of the tape-like yarn B in the woven fabric area is 0.30 to 3.

00. The sum of the ratio A and the ratio B is 0.700 or more, The woven fabric is characterized in that the yarn C satisfies at least one of the following conditions (A) and (B). (A) Yarn C has a ratio C of the area of ​​the portion of yarn C overlapping with tape-shaped yarn A to the woven fabric area of ​​0.182 or less. (B) The visible light transmittance of yarn C is 70% or more.

2. 2. The woven fabric according to claim 1, wherein the tape-shaped yarn A contains at least one selected from the group consisting of tungsten oxide, indium-doped tin oxide, and lanthanum hexaboride.

3. 3. The woven fabric according to claim 1, wherein the tape-shaped yarn B contains titanium oxide having a number average particle size of 500 to 2500 nm.

4. 3. The woven fabric according to claim 1, wherein at least one surface of the tape-shaped yarn B is a color other than white or yellow.

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