JP2011195792A - Exothermic light-transmitting sheet and exothermic light-transmitting film roof structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-transmitting sheet having a high transmittability in a visible light region and raising temperature by absorbing near infrared rays, and a film roof structure capable of preventing generation of dew condensation and controlling the state of snow accretion on a roof one by one.SOLUTION: The light-transmitting sheet has a heat conversion resin layer. The heat conversion resin layer has a sea-island phase structure comprising an incompatible mixture due to a synthetic resin blend, and. in the sea-island phase structure, either one phase of a sea component phase or an island component phase includes at least one kind of near infrared ray-absorbing material selected from near infrared ray-absorbing inorganic compound particles and near infrared ray-absorbing organic pigments and the other phase includes particles comprising a light-dispersing material to obtain the resin layer. Moreover, in the film structure constructed by using the exothermic light-transmitting sheet, near infrared rays can be converted to heat energy by irradiating near infrared rays to the exothermic light-transmitting sheet to prevent the generation of inside dew condensation, and the light-transmitting film roof structure capable of controlling the state of snow accretion on the roof one by one can be obtained.

Description

  The present invention relates to an exothermic translucent sheet that absorbs near infrared rays and raises its temperature, and an exothermic translucent membrane roof structure using the sheet. More specifically, the present invention has high transparency in the visible light region, and a film structure such as an amusement space, an event space, a rainy field, a tent warehouse, an event tent, an agricultural horticultural house, and a lighting structure thereof. Exothermic translucent sheet that can be suitably used for the film, and it is used for the roof material of the membrane structure, and when the near-infrared ray is irradiated, the light-transmitting sheet converts the near-infrared ray into thermal energy, thereby the near-infrared ray The present invention relates to an exothermic translucent membrane roof structure that absorbs heat and generates heat to prevent internal dew condensation, and can sequentially melt and remove snow on the roof.

  Tent warehouses, event tents, work tents, agricultural and horticultural houses, amusement spaces, event spaces, rain playgrounds, and other membrane structures covered with composite sheets made of fiber fabric and synthetic resin are flexible and easy to assemble and install. It is widely used because of its high outdoor durability. However, especially in these applications, in a membrane structure that forms a sealed space, condensation may occur on the inner surface of the sheet depending on the season. This dripping of condensation has problems such as wetting the goods being stored in a tent warehouse, discoloring leaves and fruits, and causing disease in an agricultural and horticultural house. In addition, due to snowfall on these membrane structures, the roof portion often deformed by the weight of snow, or the internal environment was darkened by blocking sunlight transmission due to snow accumulation.

  Concerning condensation, by providing a heat insulating layer, for example, a foamed resin layer, on the sheet, a decrease in the sheet inner surface temperature can be reduced and condensation can be suppressed, but in order to obtain a sufficient effect, several millimeters to 1 A foamed resin layer of about a centimeter is required, and the sheet for forming the membrane structure is not practical. In addition, an attempt to absorb condensed water by providing a layer having a water absorption capability on the inner side of the sheet and prevent condensation is also disclosed. (For example, refer to Patent Documents 1 and 2) However, there is a limit to the water absorption capacity, and only a certain amount of moisture can be absorbed, which causes a problem that the sheet becomes heavier and mold is likely to grow. An attempt to suppress the generation of water droplets by making the sheet inner surface hydrophilic is also disclosed. (For example, refer to Patent Document 3) According to this method, the attached water spreads and it becomes difficult to form water droplets, but a guiding structure for escaping condensed water to the ground is necessary, and the appearance inside the membrane structure is improved. Make it worse.

  With regard to snow accumulation, it is dangerous for people to climb on a membrane structure without a foothold and directly drop snow manually. In snowy areas, it is possible to take measures such as dropping the gravity at a sharp angle, but it is difficult to implement such a design in areas where snow rarely falls. In addition, attempts have been made to drop snow using the slipperiness of fluororesin (see, for example, Patent Document 4). The snowfall effect could not be obtained. In addition, a method has been proposed in which a sheet having an infrared absorbing layer is used, the temperature of the sheet is increased by receiving sunlight, and snow is removed while melting. (For example, refer to Patent Document 5) However, it is difficult to use the effect of sunlight when snowing at night or snowing for a long time. Furthermore, a method for preventing snow accretion by incorporating a heater in the roofing material has been proposed (see, for example, Patent Document 6), but the apparatus and cost are large, and the roof portion of the membrane structure is made heavy, and at the same time, the daylighting property is increased. Had the problem of damaging.

  As described above, there is no membrane structure that can prevent the occurrence of condensation, control the snowfall on the roof, and obtain high daylighting properties. It has been desired to obtain a membrane roof structure obtained by using a sheet that can control the snowfall state on the roof one after another.

JP 58-024439 A JP 05-336846 A Japanese Patent Application Laid-Open No. 07-102094 Japanese Patent Laid-Open No. 04-085369 JP 2006-009452 A JP-A-10-292565

  The present invention provides an exothermic translucent sheet that is excellent in daylighting (transmission of visible light) and absorbs near-infrared light and raises its temperature in order to solve the above-described problems of the prior art. When used in materials, when near infrared rays are irradiated, the light transmission sheet converts near infrared rays into thermal energy, preventing internal condensation, and heat generation that can sequentially melt and remove snow on the roof. It aims at providing a transparent translucent membrane roof structure.

  In order to solve the above problems, the inventors of the present invention, as a result of intensive studies, in a light-transmitting sheet having a heat-converting resin layer, the sea-island consisting of an incompatible mixture of a synthetic resin blend in the heat-converting resin layer. In the sea-island phase structure, at least one near-infrared ray selected from the near-infrared-absorbing inorganic compound fine particles and the near-infrared-absorbing organic dye in any one of the sea component phase and the island component phase. It is a phase containing an absorptive substance and the other phase contains particles made of a light diffusing substance. In this way, an exothermic translucent sheet that is equivalent to or better than containing these near-infrared-absorbing substances can be obtained and used as a membrane structure roofing material. Infrared heat By converting to rugi, it is found that heat generation prevents condensation inside the membrane structure, and an exothermic translucent membrane roof structure that can sequentially melt and remove the snow falling on the roof can be obtained, The present invention has been completed.

That is, the exothermic translucent sheet of the present invention is a light transmissive sheet having a heat-convertible resin layer, and the heat-convertible resin layer has a sea-island phase structure made of an incompatible mixture of a synthetic resin blend, In the sea-island phase structure, at least one near-infrared absorbing substance selected from the near-infrared-absorbing inorganic compound fine particles and the near-infrared-absorbing organic dye is used as one of the sea component phase and the island component phase. It is preferable that the other phase contains particles made of a light diffusing substance. In the exothermic translucent sheet of the present invention, an antifouling layer is preferably provided on the outermost layer of the light transmitting sheet. The exothermic translucent sheet of the present invention preferably has a static contact angle with water on the surface of the antifouling layer of 15 to 50 °. The exothermic translucent sheet of the present invention preferably has a static contact angle with water on the surface of the antifouling layer of 80 to 110 °. Exothermic translucent sheet of the present invention, the near-infrared absorbing inorganic compound particles, tungsten oxide, the composite tungsten oxide, represented by the hexaboride (general formula XB _6, X is Y, La, Ce, Pr Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Zr, Ba, Sr and Ca, one or two elements), and hydrotalcites It is preferable to include one or more of the above. In the exothermic translucent sheet of the present invention, the near-infrared absorbing organic dye is selected from phthalocyanine compounds, naphtholquinone compounds, imonium compounds, anthraquinone compounds, aminium compounds, and nickel-thiol complex compounds. It is preferable that 1 or more types are included. In the exothermic translucent sheet of the present invention, it is preferable that the particles made of the light diffusing substance contain at least one selected from ceramic particles, interference mica particles, glass beads, glass particles, resin beads and resin particles. The exothermic translucent sheet | seat of this invention WHEREIN: It is preferable that the said light transmissive sheet | seat is a laminated body which contains a coarse knitted fabric as a base fabric. The exothermic translucent membrane roof structure of the present invention is a membrane structure having a light transmissive sheet having a heat-convertible resin layer as a roof material, and the heat-convertible resin layer has a sea-island phase structure, In the sea-island phase structure, at least one near-infrared absorbing substance selected from the near-infrared-absorbing inorganic compound fine particles and the near-infrared-absorbing organic dye is used as one of the sea component phase and the island component phase. It is preferable that the near-infrared light is converted into thermal energy when the light-transmitting sheet is irradiated with near-infrared light by containing particles made of a light diffusing substance. In the exothermic translucent membrane roof structure of the present invention, an antifouling layer is preferably provided on the outermost layer of the light transmitting sheet. In the exothermic translucent membrane roof structure of the present invention, the light transmissive sheet is preferably a laminate including a coarse knitted fabric as a base fabric.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the exothermic translucent sheet | seat which has the high transmittance | permeability of visible region, and absorbs near infrared rays efficiently, and generate | occur | produces heat | fever, It is used for a membrane structure roof material, and exothermic translucency is provided. By irradiating the light sheet with near-infrared rays, condensation on the inner surface of the sheet can be prevented, and the snow on the roof can be controlled sequentially to prevent the load on the structure due to snow load. It is possible to provide a translucent membrane roof structure capable of ensuring the above.

1 shows an example of an exothermic translucent sheet according to the present invention, in which a heat-convertible resin layer has a sea-island phase structure, an island component phase includes a near-infrared absorbing material, and a sea component phase is composed of a light-diffusing material. The figure which shows the state including 1 shows an example of an exothermic translucent sheet of the present invention, in which the heat-convertible resin layer has a sea-island phase structure, the island component phase includes particles made of a light diffusing material, and the sea component phase is a near-infrared absorbing material. The figure which shows the state which includes The figure which shows a tent warehouse as an example of the exothermic translucent membrane roof structure of this invention Figure showing a tent for an event as an example of the exothermic translucent membrane roof structure of the present invention The figure which shows an agricultural and horticultural house as an example of the exothermic translucent membrane roof structure of this invention The figure which shows the structure which evaluated the exothermic property in an Example and a comparative example. The figure which shows the structure which evaluated the condensation prevention property in an Example and a comparative example The figure which shows the structure which evaluated snow-sliding property in the Example and the comparative example The figure which shows the structure which evaluated snow melting property in the Example and the comparative example.

  The exothermic light-transmitting sheet of the present invention is a light-transmitting sheet having a heat-converting resin layer, and the heat-converting resin layer has a sea-island phase structure composed of an incompatible mixture of a synthetic resin blend, Either one of the sea component phase or the island component phase of the phase structure contains at least one near infrared absorbing material selected from near infrared absorbing inorganic fine particles and near infrared absorbing organic dyes. In the phase, the other phase contains particles made of a light diffusing substance, so that the resin layer has high exothermic properties when absorbing near infrared rays while having high translucency (transmittance of visible light). An exothermic translucent sheet is obtained which is equivalent to or better than containing these near-infrared absorbing materials as a whole. The form is a base fabric-containing laminate including a resin sheet (resin film) or a coarse knitted fabric as a base fabric. The resin sheet can be molded by a method such as a calendar molding method, a T-die extrusion method, or a casting method, and the heat-generating translucent sheet may be a single heat-convertable resin layer. The laminated body which laminated | stacked the some resin sheet containing may be sufficient. The base fabric-containing laminate is a method of laminating a film or sheet molded by a calendar molding method, a T-die extrusion method, a casting method or the like with an adhesive layer interposed on one or both sides of the coarse knitted fabric, or the coarse knitted fabric Can be produced by a method of laminating and heating both sides of the film via a void, and it is sufficient that these films or sheets contain at least one heat-converting resin layer. A convertible resin layer may be used. The visible light transmittance (JISZ8722.5.4 (condition g)) of the exothermic translucent sheet of the present invention is preferably 40 to 90% in the case of a resin sheet and 30 to 80% in the case of a base fabric-containing laminate. .

  In the present invention, the heat-converting resin layer is molded by a known processing method by melting a synthetic resin blend or by stirring a liquid synthetic resin in a synthetic resin blend. Synthetic resins preferably used in the present invention include, for example, vinyl chloride resins, vinyl chloride copolymer resins, olefin resins (PE, PP, etc.), olefin copolymer resins, urethane resins, urethane copolymer resins. , Acrylic resin, acrylic copolymer resin, vinyl acetate resin, vinyl acetate copolymer resin, styrene resin, styrene copolymer resin, polyester resin (PET, PEN, PBT, etc.), polyester copolymer resin Fluorine-containing copolymer resin, silicone resin, silicone rubber, polycarbonate, polyamide, polyether, polyesteramide, polyphenylene sulfide, polyetherester, vinylester resin, unsaturated polyester resin, etc. Listed thermoplastic and curable resins It is.

  The heat-convertible resin layer in the present invention has a sea-island phase structure composed of an incompatible mixture of a synthetic resin blend, and the combination of the synthetic resin blend is not particularly limited as long as it is incompatible. Examples of incompatible combinations include vinyl chloride resin and polyethylene, vinyl chloride resin and polypropylene, vinyl chloride resin and styrene resin, vinyl chloride resin and styrene copolymer resin, vinyl chloride resin and silicone resin, vinyl chloride resin and fluorine. Containing copolymer resin, vinyl chloride resin and vinyl ester resin, polystyrene and polyethylene, polystyrene and polypropylene, urethane resin and polyethylene, urethane resin and polypropylene, polyester resin and polyethylene, polyester resin and polypropylene, polyamide and polycarbonate, acrylic resin and polystyrene A blend of two kinds of synthetic resins such as acrylic resin and polycarbonate, polyamide and polystyrene, polyamide and polypropylene is preferable. Another kind of resin can be further contained with respect to these incompatible flexible resin pairs.

  These incompatible mixtures preferably have a sea-island phase structure with a cloudy appearance showing a phase separation structure. In this sea-island phase structure, the sea component phase and the island component phase are composed of different types of resins. For example, in an incompatible mixture composed of synthetic resin A and synthetic resin B, by setting the ratio of synthetic resin A and synthetic resin B, The sea component phase can be composed of synthetic resin A, the island component phase can be composed of synthetic resin B, the sea component phase can be composed of synthetic resin B, and the island component phase can be composed of synthetic resin A. . In addition, when the thermoplastic resin C is further different from the incompatible thermoplastic resin pair AB, the island component phase is composed of the island component phase by the thermoplastic resin B and the thermoplastic resin C in the sea-island phase structure. The island component phase may be composed of an island component phase. Similarly, the island component phase may be composed of an island component phase made of the thermoplastic resin A and an island component phase made of the thermoplastic resin C. The heat-convertible resin layer has a sea-island phase structure, and either the sea component phase or the island component phase is a phase containing a near-infrared absorbing material, and the other phase is a particle made of a light diffusing material. By containing near-infrared light when it is irradiated, the near-infrared absorbing material contained in the other phase is scattered in the phase containing particles made of a light diffusing substance. It can be efficiently absorbed and converted to heat energy, and high exothermic properties can be obtained without including a near infrared absorbing substance in the entire resin layer. On the other hand, in the phase containing particles composed of a light diffusing substance, by suppressing the scattering of visible light, the visible light transmittance (JISZ8722.5.4) is higher than when the near infrared absorbing substance is contained in the entire resin layer. (Condition g)) can be obtained.

  The ratio of the synthetic resin constituting the island component phase is preferably 3 to 50% by volume, more preferably 5 to 40% by volume with respect to the volume of the synthetic resin constituting the sea component phase. 2.9-33.3 volume% is preferable and, as for the island component content rate with respect to the whole heat converting resin layer which has a sea island phase structure, 4.7-28.6 volume% is more preferable. If the island component content is less than 2.9% by volume with respect to the entire heat-converting resin layer having a sea-island phase structure, the exothermic effect may be insufficient when a near-infrared absorbing substance is contained in the island component phase. When the near-infrared absorbing substance is contained in the sea component phase, there is no difference from the case where there is no sea-island phase structure. On the other hand, if the island component content exceeds 33.3% by volume, the resin strength of the heat-converting resin layer is lowered, and the strength and durability of the resulting sheet are lowered, which is not preferable. The island component phase has a spherical shape, a distorted spherical shape, a meteorite shape, a rugby ball shape, and the like. The average particle size of the island component phase is 0.4 to 30 μm, and 1 to 20 μm is particularly preferable. When the average particle size of the island component phase is larger than 0.4 μm, the near infrared ray is scattered inside the heat-convertible resin layer, and is easily absorbed by the near infrared absorbing material contained in the sea component phase or the island component phase. On the other hand, since the scattering of visible light is suppressed, a good near-infrared absorption effect can be obtained while maintaining a high visible light transmittance. When the average particle size of the island component phase is less than 0.4 μm, near-infrared scattering is reduced while visible light scattering is increased, and the near-infrared absorption effect and visible light transmittance may be reduced. If the average particle size of the island component phase exceeds 30 μm, visible light may be reflected and the visible light transmittance may be reduced. In the present invention, the thickness of the heat-convertible resin layer having a sea-island phase structure is 0.03 to 1.0 mm, preferably 0.05 to 0.5 mm. When the thickness of the heat-converting resin layer is less than 0.03 mm, sufficient heat generation may not be obtained. When the thickness exceeds 1.0 mm, the texture of the obtained sheet becomes hard, which causes problems in productivity and handleability. May occur.

The tungsten oxide used for the near-infrared absorbing inorganic fine particles in the heat-converting resin layer of the present invention is expressed as WyOz (W: tungsten, O: oxygen), and 2.2 ≦ z / y <3. It is preferably 0. In tungsten trioxide (WO ₃ ), effective free electrons do not exist, so there are few absorption characteristics in the near infrared region, and it is not very effective as a near infrared absorbing material. If z / y is 2.2 or more, it is possible to avoid the appearance of the WO ₂ crystal phase in the tungsten oxide, and it is possible to obtain chemical stability as a material. In the present invention, the composite tungsten oxide fine particles used for the near infrared absorbing inorganic fine particles have the formula MxWyOz (where M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P , S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, I, Cs, one or more elements, W is tungsten, O is Oxygen), and preferably 0.001 ≦ x / y ≦ 1, 2.2 ≦ z / y ≦ 3. By adding element M to tungsten oxide to form a composite tungsten oxide, free electrons are generated in the composite tungsten oxide, and free electron-derived absorption characteristics are exhibited in the near infrared region, and the near infrared absorptivity. Effective as a substance. Here, if the value of x / y indicating the addition amount of the element M is larger than 0.001, a sufficient amount of free electrons is generated, and the intended near infrared absorptivity can be obtained. As the amount of the element M added increases, the supply amount of free electrons increases and the near-infrared absorptivity also increases. However, when the value of x / y is about 1, the effect is saturated. Moreover, it is preferable that the value of x / y is smaller than 1 because it is possible to avoid the generation of an impurity phase in the near infrared absorbing material. On the other hand, the value of z / y indicating the control of the amount of oxygen is preferably 2.2 ≦ z / y <3.0, similar to the above-described tungsten oxide, but in the case of composite tungsten oxide, z / y = Even if it is 3.0, the supply of free electrons due to the addition of the element M is effective as a near-infrared absorbing substance. The average particle size of the tungsten oxide or composite tungsten oxide is preferably 1 to 1000 nm, and more preferably 2 to 200 nm. When the average particle diameter exceeds 1000 nm, the concealing property of the resin containing particles is increased, and the visible light transmittance may be lowered. As the average particle size is smaller, the concealing property is lowered. When the average particle size is 200 nm or less, a heat-convertible resin layer having a high visible light transmittance can be obtained, but particles less than 1 nm are difficult to obtain, and into the resin. Is difficult to disperse. The tungsten oxide or composite tungsten oxide contained in the sea component phase or island component phase is preferably 0.001 to 5 parts by mass with respect to 100 parts by mass of the synthetic resin constituting the sea component phase or island component phase. 005-3 mass parts is more preferable. If it is less than 0.001 part by mass, the near infrared absorption effect by addition becomes insufficient, and sufficient near infrared absorptivity may not be obtained. Even when added in excess of 5 parts by mass, the near-infrared absorption effect is only slightly improved, and when the amount added is increased, the transmitted color shows a deep blue color, the visible light transmittance is reduced, and economically Disadvantageous.

6 boride in a heat conversion resin layer of the present invention used in the near-infrared absorbing inorganic compound fine particles is a compound represented by the general formula XB _6. (X is one or two selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Zr, Ba, Sr and Ca. Element, B is boron) 6 boride has absorption in the near-infrared region, and can be added to provide exothermic properties. The average particle size of the hexaboride particles is preferably 1 to 800 nm, and more preferably 2 to 200 nm. When the average particle diameter exceeds 800 nm, the concealability of the resin containing the particles increases, and the visible light transmittance may decrease. The smaller the average particle diameter, the lower the concealability. If it is 200 nm or less, a heat-converting resin layer having a higher visible light transmittance can be obtained, but particles less than 1 nm are difficult to obtain, and the resin Difficult to disperse in. 0.001-5 mass parts is preferable and, as for the addition amount of the hexaboride with respect to 100 mass parts of resin which comprises a sea component phase or an island component phase, 0.005-3 mass parts is more preferable. If the addition amount is less than 0.001 part by mass, the near infrared absorption effect by addition becomes insufficient, and sufficient near infrared absorptivity may not be obtained. Even if added in excess of 5 parts by mass, the effect of improving the near infrared absorptivity is slight, and when the amount added is increased, the transmitted color shows a dark green color, the visible light transmittance decreases, and economically Is also disadvantageous.

The hydrotalcite compound used for the near-infrared absorbing inorganic fine particles in the heat-converting resin layer of the present invention is represented by the general formula [M 2 ⁺ _1-x M ³⁺ _x (OH) ₂ ] [A ⁿ⁻ _{x / n} · mH. ₂ O] is a double hydroxide having a layer structure. (In the formula, M ²⁺ represents a divalent metal ion such as Mg ²⁺ , Fe ²⁺ , Zn ²⁺ , Ca ²⁺ , Li ²⁺ , Ni ²⁺ , Co ²⁺ , Cu ²⁺ , and M ³⁺ represents Al ³⁺ , Fe ³⁺ , Mn ^{3+. ,} an in ^3+, represents a trivalent metal ion ^{Ce 3+} or the ^{like, a n-is OH -, F -, Cl -} , Br -, NO 3-, CO 3 2-, SO 4 2-, Fe (CN) ₆ ³⁻ , CH ₃ COO ⁻ , an n-valent interlayer anion such as an oxalate ion, a salicinate ion, and an alkylbenzenesulfonate ion, and x and m are 0 <x <0.5 and 0 ≦ m, respectively. Hydrotalcite compounds (in the range) have a refractive index of about 1.5, which is close to the refractive index of a general resin, so there is almost no light scattering at the interface between the hydrotalcite compound and the resin, and visible light The absorption of light in the area Since Tondo no there is almost no decrease in the change and the visible light transmittance of the color it is added to the resin. Moreover, since it has absorption in the infrared region, by adding this, it is possible to improve the near infrared absorption while minimizing the influence on the hue and visible light transmittance. The amount of the hydrotalcite compound added to 100 parts by mass of the resin constituting the sea component phase or island component phase is preferably 0.1 to 15 parts by mass, and more preferably 0.5 to 10 parts by mass. If the addition amount is less than 0.1 parts by mass, the effect of addition may not be obtained. Even if the addition amount exceeds 15 parts by mass, the effect of improving near-infrared absorption is slight, and the resin layer becomes hard. Flexibility may be impaired. The average particle diameter of the hydrotalcite compound particles is preferably 0.01 to 10 μm from the viewpoint of dispersibility in the resin, and more preferably 0.1 to 3 μm.

  In the present invention, the tungsten oxide, composite tungsten oxide, hexaboride, and hydrotalcite compound have a surface of silica, alumina, silica-alumina, and higher fatty acid in order to improve dispersibility in the resin. What was covered with etc. may be used.

  1 selected from a phthalocyanine compound, a naphtholquinone compound, an imonium compound, an anthraquinone compound, an aminium compound, and a nickel-thiol complex compound as the near infrared absorbing organic dye in the heat-converting resin layer of the present invention. It is preferable to use at least seeds, which are disclosed in JP-A-51-135886, JP-A-56-143242, JP-A-58-13676, JP-A-60-23451, JP-A-61. -115958, JP-A-63-295578, JP-A-4-174402, JP-A-5-93160, JP-A-5-222302, and JP-A-6-264050. It can be selected from known dyes. The near-infrared absorbing organic pigment contained in the sea component phase and the island component phase is preferably 0.01 to 3.0 parts by mass with respect to 100 parts by mass of the synthetic resin constituting the sea component phase or the island component phase. 0.1-2.0 mass parts is especially preferable. If the addition amount is less than 0.01 parts by mass, the near infrared ray absorbing effect is insufficient, and sufficient exothermic properties may not be obtained. Even if added over 3.0 parts by mass, the effect of improving the near infrared absorptivity is slight, and when the amount added is increased, the transmitted color shows a deep coloring, and the visible light transmittance may decrease. is there.

  In the heat-convertible resin layer of the present invention, the near-infrared-absorbing inorganic compound fine particles and the near-infrared-absorbing organic dye as the near-infrared absorbing substance contained in either the sea component phase or the island component phase Only one type selected from among them may be used, or two or more types may be used in combination. When two or more types are used in combination, the amount of the near-infrared absorbing substance contained in the resin can be determined according to the respective characteristics, but with respect to 100 parts by mass of the resin constituting the sea component phase or the island component phase. It is preferable that each addition amount is within the above-mentioned range and 0.01 to 15 parts by mass in total, and more preferably 0.1 to 6 parts by mass. These near-infrared absorbing substances are contained only in either the sea component phase or the island component phase at the above-mentioned addition amount, so that they absorb near infrared rays without disturbing the transmission of visible light. It can be converted into thermal energy.

  In the heat-convertible resin layer of the present invention, either the sea component phase or the island component phase contains the near-infrared absorbing material, and the other phase contains particles made of a light diffusing material. In this way, the near infrared rays can be scattered by the phase containing the light diffusing substance and absorbed by the phase containing the near infrared absorbing substance, and the near infrared ray can be irradiated to the light transmitting sheet having the heat converting resin layer. In this case, high exothermic properties can be obtained. In the present invention, as the light diffusing substance, particles made of at least one kind of light diffusing substance selected from ceramic particles, interference mica particles, glass beads, glass particles, resin beads and resin particles are preferably used.

As ceramic particles used in the present invention, titanium oxide, zinc oxide, aluminum oxide (alumina), magnesium oxide, tungsten oxide (WO ₃ ), zirconium oxide (zirconia), tin oxide, indium oxide, silicon dioxide, aluminum borate, Particles made of ceramics such as magnesium borate, zirconium silicate, aluminum nitride, silicon nitride, boron nitride, titanium nitride, zirconium boride, phosphorus boride, and molybdenum silicide, or composite ceramics thereof are preferably used. Among these, titanium oxide, tungsten oxide (WO ₃ ), tin oxide, zinc oxide, and zirconium oxide (zirconia) having a low absorption in the visible light region and a high refractive index are particularly preferably used. The average particle diameter of the ceramic particles varies depending on the refractive index, but is preferably 0.3 to 3.0 μm, and more preferably 0.4 to 2.1 μm. By setting the average particle diameter within this range, it is possible to suppress the scattering of visible light in the phase containing the light diffusing material and to effectively scatter near infrared rays. When the average particle diameter of the ceramic particles exceeds 3.0 μm, the concealing property of the resin containing the particles increases, and the visible light transmittance may decrease. When the average particle diameter is less than 0.3 μm, the near-infrared scattering effect is not good. In addition, the visible light transmittance may be reduced by scattering visible light. The addition amount of the ceramic particles in the phase containing the light diffusing material is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin constituting the phase. preferable. If the addition amount is less than 0.01 parts by mass, the near-infrared scattering effect is insufficient, and sufficient exothermic properties may not be obtained. When the addition exceeds 20 parts by mass, the visible light transmittance may be lowered, and the resin strength may be lowered to adversely affect the durability of the resulting exothermic translucent sheet. In order to improve the dispersibility in the resin, the ceramic particles may be those whose surfaces are coated with silica, alumina, silica / alumina, higher fatty acid and the like. The ceramic particles have higher thermal conductivity than the resin, and by using these, the heat of the heat-converting resin layer can be transferred to the surface of the heat-generating translucent sheet more quickly and used for the film structure. In this case, it is possible to more effectively prevent the occurrence of condensation inside the membrane structure and sequentially melt and remove the snowfall on the roof.

As the interference mica particles used in the present invention, the surface of the mica particles is coated with a titanium oxide thin film or a thin film having a multilayer structure of three layers of titanium oxide / silicon oxide / titanium oxide (TiO ₂ / SiO ₂ / TiO ₂ ). Preferably, the light interference particles are used. The average particle diameter of the interference mica particles is preferably 1 to 100 μm, and more preferably 5 to 60 μm. When the average particle size exceeds 100 μm, the resin containing the material exhibits a metallic luster and the visible light transmittance may be lowered. When the average particle size is less than 1 μm, the near infrared light may not be sufficiently scattered. The amount of interference mica particles added in the phase containing the light diffusing material is preferably 0.01 to 20 parts by mass, and 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin constituting the phase. More preferred. If the addition amount is less than 0.01 parts by mass, the near-infrared scattering effect is insufficient, and sufficient exothermic properties may not be obtained. When the addition exceeds 20 parts by mass, the visible light transmittance may be lowered, and the resin strength may be lowered to adversely affect the durability of the resulting exothermic translucent sheet.

  Examples of the glass beads used in the present invention include hollow glass beads and solid glass beads, and examples of the glass particles include glass powder and broken glass beads. Examples of the resin beads used in the present invention include resin beads made of acrylic resin, silicone resin, polystyrene resin, polyurethane resin, polyethylene resin, benzoguanamine resin, epoxy resin, and the like. -It may have a shell multilayer structure, and may have a crosslinked structure. The resin particles are amorphous particles obtained by crushing these resin beads. The average particle diameter of the glass beads, glass particles, resin beads, and resin particles is preferably 1 to 20 μm, and more preferably 1 to 8 μm. If the average particle diameter exceeds 20 μm, the visible light scattering in the phase containing the light diffusing material may be strong and the visible light transmittance may be reduced. If the average particle diameter is less than 1 μm, the near-infrared scattering is not good. May be enough. The addition amount of the glass beads, glass particles, resin beads, or resin particles in the phase containing the light diffusing material is 0.1 to 50 with respect to 100 parts by mass of the resin constituting the phase containing the light diffusing material. It is preferable that it is a mass part, and 1-20 mass parts is more preferable. If the addition amount is less than 0.1 parts by mass, the near-infrared scattering effect may be insufficient, and sufficient heat generation may not be obtained. If the amount exceeds 50 parts by mass, the visible light transmittance may be lowered, and the resin strength may be lowered, which may adversely affect the durability of the resulting exothermic translucent sheet.

The particles made of the light diffusing substance may be used by selecting one of the above, or may be used in combination of two or more. When two or more types are used in combination, the amount of particles made of a light diffusing substance contained in the resin can be determined according to the respective characteristics, but the resin 100 constituting the near-infrared absorbing substance-free phase. It is preferable that each addition amount with respect to a mass part is in said range, and is 0.01-50 mass parts in total, and 0.1-20 mass parts is more preferable. Of the particles made of a light diffusing substance, titanium oxide, tungsten oxide (WO ₃ ), tin oxide, zinc oxide, zirconium oxide (zirconia), and interference mica particles, which are ceramics having a high refractive index, are particularly preferably used. When using in combination of seeds or more, it is preferable to use a combination containing these.

  Since the heat-convertible resin layer of the present invention has a sea-island phase structure and contains a near-infrared absorbing substance only in either the sea component phase or the island component phase, the near-infrared ray for the hue of the heat-generating translucent sheet The influence of the absorbing inorganic compound fine particles and the near-infrared absorbing organic dye is suppressed to a low level, and it is also possible to add a pigment to the sea component phase and / or the island component phase for coloring. In particular, a heat-convertible resin layer containing only a near-infrared absorbing substance only in the island component phase is preferable because it is less colored by the near-infrared absorbing substance and has a high degree of freedom in coloring with a pigment. The pigment used for coloring is not particularly limited, and can be appropriately selected from conventionally known organic pigments and inorganic pigments. In addition, fluorescent pigments, phosphorescent pigments, fluorescent brighteners, and the like can be used as necessary. I can do it. The heat-convertible resin layer of the present invention may also contain known additives in addition to the sea component phase and the island component phase. Examples of the additive include an antistatic agent, a flame retardant, a plasticizer, a flexibility imparting agent, a filler, an adhesive, a crosslinking agent, an ultraviolet absorber, an antioxidant, a stabilizer, a lubricant, a processing aid, and an antibacterial agent. Examples thereof include agents and fungicides.

  In the exothermic translucent sheet of the present invention, an antifouling layer is provided on at least the outermost layer on the front side of the light transmitting sheet in order to prevent a decrease in visible light transmittance due to adhesion of dirt over time and to maintain an aesthetic appearance. Is preferably provided. As long as the antifouling layer does not impair the visible light transmittance of the exothermic translucent sheet and does not have an extreme concealing property, the formation method and the material thereof are not particularly limited. Such an antifouling layer is, for example, a coating film formed by applying a resin solution or a resin dispersion composed of at least one of an acrylic resin or a fluorine resin solubilized in a solvent, silica fine particles, or A coating containing colloidal silica, a coating containing an organosilicate and / or its condensate to form a hydrophilic coating layer, a coating containing a photocatalytic inorganic material (eg photocatalytic titanium oxide) and a binder It can be appropriately selected from those in which a photocatalyst layer is formed by applying an agent, and those obtained by laminating a film having at least the outermost surface formed of a fluororesin by an adhesive or hot melt processing. Between the light transmission sheet and the antifouling layer, if necessary, an adhesive layer for improving the adhesion between the light transmission sheet surface and the antifouling layer, or a photocatalyst when the antifouling layer contains a photocatalytic substance. A protective layer for preventing the resin from decomposing, an additive migration preventing layer for preventing the additive contained in the resin constituting the light transmitting sheet from migrating to the antifouling layer, and the like may be formed. In addition, if necessary, the antifouling layer on the surface opposite to the surface on which the antifouling layer is formed, an antifouling layer for preventing the exothermic translucent sheet from being damaged, and the exothermic translucent sheet Conventionally known methods such as an additive migration preventing layer for preventing the additive contained in the resin layer on the opposite side from migrating onto the antifouling layer, while being rolled up and stored May be formed.

  In the exothermic translucent sheet of the present invention, the static contact angle with respect to water on the surface of the antifouling layer provided in the outermost layer is preferably 15 to 50 °, and more preferably 15 to 30 °. When the static contact angle is 50 ° or less, even if dirt adheres to the surface, it is easy to be washed away by rain, etc., and moreover, when the rain containing dirt tends to spread out when it flows on the surface, streak-like dirt is removed. Hard to remain. Moreover, the melted water due to the snow at the beginning of falling forms a water film on the surface of the heat-generating translucent sheet, and the subsequent snowfall can be efficiently dissolved. When the static contact angle is 15 ° to 50 °, if there is snowfall when the membrane structure is not irradiated with near infrared rays, it is easy for snow to adhere and snow accumulation occurs. By melting the snow in the part touching the light sheet, a water film is formed between the surface of the heat-generating translucent sheet and the snow, and the snow can be easily slid down. If the static contact angle is less than 15 °, it is easier for snow to adhere, more likely to accumulate snow, and even if the snow that touched the sheet is melted by irradiating near infrared rays, the melted water will spread quickly. It is difficult to form a water film between the seat surface and the snow, and it may take time for the snow to slide down. The static contact angle with respect to water on the surface of the antifouling layer provided in the outermost layer is also preferably 80 to 110 °, more preferably 95 to 110 °. When the static contact angle is 80 ° or more, it is difficult for dirt to adhere to the surface, and characteristics that can be easily removed even if dirt is attached are obtained. Furthermore, when the static contact angle is 80 ° or more, it is difficult for snow to adhere, and even if there is snowfall when the membrane structure is not irradiated with near infrared rays, it is difficult to cause snow accumulation in the initial stage, and there is some snowfall. Even if it exists, snow can be slid down and removed by irradiating near infrared rays and melting the snow of the part which has touched the exothermic translucent sheet | seat. An antifouling layer with a static contact angle exceeding 110 ° is difficult to use with ordinary processing methods such as solution coating and film lamination, even if fluorine resin is used, and requires special processing methods such as sputtering and plating. Therefore, there is no versatility, and even if the static contact angle exceeds 110 °, the above effect is not so improved. If the static contact angle of the antifouling layer surface with water is more than 50 ° and less than 80 °, dirt is likely to adhere to the surface, and the attached dirt is difficult to remove and is not easily washed away by rain or the like. is there. Moreover, the effect of preventing the adhesion of snow is low at the initial stage, and even if the snow is melted by irradiating near infrared rays, the slipperiness of the snow is insufficient, and it may take time to slide down.

  It is preferable that at least the front surface side of the exothermic translucent sheet of the present invention is smooth, and the unevenness thereof has a ten-point average roughness Rz value (JIS B0601-1994) of preferably less than 30 μm, and less than 15 μm. It is more preferable that Since the surface facing the outside is smooth, the heat raised by the near-infrared radiation is easily transferred to the snow, and the efficiency of snow melting is improved. Furthermore, it becomes difficult for snow to stay on the roof in the early stage of snowfall, and it is difficult to generate snow. As a method for obtaining such a smooth surface, for example, one surface of the sheet is smoothed by mirror embossing, or a smooth molding film (for example, a polyester film) is formed by a calendar molding method, a T-die extrusion method, or a casting method. Examples of the method include a method of peeling off and removing the process film after the sheet is formed by, for example.

  The exothermic translucent sheet of the present invention is preferably a laminate comprising a coarse knitted fabric as a base fabric in order to impart strength, durability, dimensional stability, and the like. Here, as the coarse knitted fabric, a coarse knitted fabric composed of yarns including warp and weft arranged in parallel with a gap between yarns (the porosity is 90% at maximum, preferably 5 to 50%) ) Can be used. The yarn constituting the coarse knitted fabric may be any of multifilament yarn, short fiber spun yarn, monofilament yarn, split yarn yarn, tape yarn yarn, etc., but the flexibility of the sheet obtained And from the viewpoint of strength, a multifilament yarn is preferred. The fibers used in the coarse knitted fabric include synthetic fibers such as polypropylene fibers, polyethylene fibers, polyester fibers, nylon fibers and vinylon fibers, natural fibers such as cotton and hemp, semi-synthetic fibers such as acetate, glass fibers, silica fibers, Examples thereof include inorganic fibers such as alumina fibers and carbon fibers, and these may be composed of single or a mixture of two or more kinds. When a woven fabric is used, it may have any structure such as plain weave, twill weave, satin weave, and patterned weave, but plain weave fabric is preferably used because it has an excellent balance of physical properties of the exothermic translucent sheet to be obtained. . When using a knitted fabric, a weft insertion tricot of Russell knitting is preferably used. The coarse knitted fabric may be subjected to water repellency treatment, water absorption prevention treatment, adhesion treatment, flame retardant treatment, and the like as necessary.

  The exothermic translucent membrane roof structure of the present invention is a membrane structure having a light transmissive sheet having a heat-converting resin layer as a roof material, and the heat-converting resin layer is an incompatible mixture by a synthetic resin blend. The sea-island phase structure is composed of any one of the sea component phase and the island component phase selected from near-infrared absorbing inorganic fine particles and near-infrared absorbing organic dyes. Containing at least one kind of near-infrared absorbing substance and containing particles made of a light diffusing substance in the other phase, when the near-infrared ray is irradiated, the near-infrared ray is converted into thermal energy, Condensation can be prevented and the snow on the roof can be melted and removed sequentially.

  In the present invention, near infrared rays include near infrared rays contained in sunlight as well as near infrared rays emitted from a near infrared irradiation device installed inside the membrane structure. As a near-infrared irradiation device, a device that emits near-infrared rays electrically is preferable to lamps, heaters, and burners that involve burning of kerosene, oil, gas, coal, etc., for reasons of disaster prevention. Specifically, it is preferable to select appropriately from a heating device such as a halogen heater or a carbon heater, or a lighting fixture such as an incandescent bulb, a halogen lamp, or a mercury lamp, and use them alone or in combination of two or more. These near-infrared irradiation devices may be devices that emit light having a wavelength in the near-infrared region (wavelength 800 to 2500 nm), and the emission peak may not necessarily be in the near-infrared region.

  Near-infrared rays are hardly absorbed by air, but are absorbed by the heat-converting resin layer and converted to thermal energy, and the temperature of the heat-generating translucent sheet rises. If the surface temperature of the exothermic translucent sheet inside the membrane structure can be maintained higher than the dew point temperature (the temperature at which water condensation starts when air containing water vapor is cooled), condensation can be prevented and the roof of the membrane structure can be prevented. If the outer exothermic translucent sheet surface temperature is maintained higher than 2 ° C., the snow falling on the roof can be melted and removed sequentially. The dew point temperature can be obtained by calculation by measuring the temperature and relative humidity inside the membrane structure, but it can also be directly measured by using a dew point meter. The surface temperature of the exothermic translucent sheet can be measured by a temperature sensor using a contact type thermocouple, a non-contact type radiation thermometer, or the like. It is always optimal by automatically adjusting on / off of the near infrared irradiation device and increasing / decreasing the output in conjunction with the measurement results of the dew point temperature and the surface temperature (front side or inside) of the exothermic translucent sheet. It is possible to maintain this state and to save power. Specifically, for example, in a membrane structure heated to 20 ° C. in the winter, the dew point temperature is about 9 ° C. when the internal relative humidity is 50%, preventing the occurrence of condensation. In order to do so, it is necessary to maintain the inner surface temperature of the exothermic translucent sheet to exceed 9 ° C. In addition, in the rainy season, for example, when the temperature in the membrane structure is 25 ° C. and the relative humidity is 90%, the dew point temperature is about 23 ° C. In order to prevent the formation of dew condensation, It is necessary to maintain the inner surface temperature above 23 ° C. In the case of using a conventional highly translucent sheet, the sheet does not absorb near infrared rays sufficiently, and in order to obtain such a sheet surface temperature, a near infrared irradiation device is arranged at a high density and a high output near It was necessary to irradiate infrared rays. On the other hand, if the sheet is a dark colored sheet, the temperature can be increased by absorbing near infrared rays sufficiently, so that a high sheet surface temperature can be obtained with a small amount of near infrared irradiation. Since the visible light transmittance is low when used in a structure, it is necessary to turn on the illumination even in the daytime on a sunny day. However, the exothermic translucent sheet used in the exothermic translucent membrane roof structure of the present invention absorbs near infrared rays contained in sunlight and rises in temperature in the daytime on a sunny day. There is almost no need to operate the irradiation device, and since the visible light transmittance is high, there is no need to turn on the illumination. Even if it is not fine weather, it is possible to obtain sufficient brightness without lighting during the day, and when the seat is below the dew point temperature or during snowfall, the near infrared irradiation device is operated appropriately to prevent internal condensation. In addition, snow on the roof can be melted and removed sequentially.

  FIG. 3 shows an example of a tent warehouse (8-1) as the exothermic translucent membrane roof structure of the present invention. A tarpaulin-type exothermic translucent sheet (1) having a heat-converting resin layer and having a coarse knitted fabric as a base fabric is used for the roof portion and the wall portion. A plurality of straight tube halogen heaters (9-1) attached with a reflecting plate for irradiating the light source are arranged at intervals toward the roof side. A dew point thermometer (not shown) is installed in the tent warehouse, and multiple contact-type thermocouple temperature sensors (not shown) are attached to the inner surface of the exothermic translucent sheet. The measured value of each temperature sensor is always dew point. By controlling the output of the halogen heater so as to exceed the temperature, condensation can be prevented. If the inside of the tent warehouse is not particularly heated, the dew point temperature may be below 2 ° C, and snow melting may not be possible with the above settings. Therefore, regardless of the dew point temperature, for example, the surface temperature of the exothermic translucent sheet By controlling the lower limit to be 2 ° C., it is also possible to melt and remove snow successively during snowfall. The exothermic translucent sheet contains a coarse knitted fabric as a base fabric, so that it has sufficient strength as a sheet for use in a tent warehouse. Since the temperature of the sheet rises by absorbing near infrared rays contained in, the generation of condensation can be prevented by not operating the halogen heater during the day or by operating at a low output. The exothermic translucent sheet allows light in the visible region to pass well, so that it can be bright enough to work inside without illumination even during sunny days, even during snowfall. Since snow can be melted and removed sequentially, light is not blocked by snow. In FIG. 3, although the halogen heater is fixed, it is possible to freely move between the main building (10) and the eaves (11) by installing rails on the aggregate (not shown) that supports the tent warehouse. It may also be possible to install a lighting device that also serves as a near-infrared irradiation device as a working light source when there is a shortage of external light, such as at night, and illumination separately from the near-infrared irradiation device A device may be installed.

  FIG. 4 shows an example of an event tent (8-2) as the exothermic translucent membrane roof structure of the present invention. This tent has a dome-shaped roof portion and a cylindrical wall portion, and a plurality of halogen lamps (9-2) are arranged toward the roof side as a near infrared irradiation device along the circumference of the upper end of the wall portion. Has been placed. A tarpaulin type exothermic translucent sheet (1) having a heat-convertible resin layer and including a coarse knitted fabric as a base fabric is used for the roof. The exothermic translucent sheet contains a coarse knitted fabric as a base fabric, has sufficient strength as a sheet used for an event tent, and has a heat-converting resin layer, so that it contains near infrared rays contained in sunlight. As the temperature of the heat-generating translucent sheet rises by absorbing water, it is possible to prevent the occurrence of condensation by turning off the halogen lamp during the daytime in fine weather or by operating at a low output. Since the exothermic translucent sheet allows light in the visible region to pass well, it is possible to obtain a brightness that can be used for setting up an event venue without lighting even if it is not sunny in the daytime. When the halogen lamp is turned on, near infrared rays contained in the radiation raise the temperature of the sheet to prevent condensation, and visible light functions as illumination for illuminating the inside of the tent. Like the above tent warehouse, it is also possible to manage the temperature of the exothermic translucent sheet using a dew point thermometer and a temperature sensor, in which case, in order to properly control the internal brightness and sheet temperature, another An illumination device or a near-infrared irradiation device can also be used in combination.

  FIG. 5 shows an example of an agricultural and horticultural house (8-3) using the exothermic translucent membrane roof structure of the present invention. This house has a skirt that is perpendicular to the arched roof, and a plurality of straight tube halogen heaters (9-1) with a reflector as a near-infrared ray irradiator inside the roof at intervals. It is arranged toward the roof side. A tarpaulin type exothermic translucent sheet (1) having a heat-convertible resin layer and including a coarse knitted fabric as a base fabric is used for the roof. A dew point thermometer (not shown) is installed in the agricultural and horticultural house, and multiple contact-type thermocouple temperature sensors (not shown) are attached to the inner surface of the exothermic translucent sheet. Condensation is prevented by controlling the output of the halogen heater so that the dew point temperature is exceeded. Moreover, it can prepare for snowfall by controlling so that the minimum of the inner surface temperature of an exothermic translucent sheet | seat may be 2 degreeC. Durability and strength (especially tear resistance) can be imparted by including the base fabric in the exothermic translucent sheet, and the visible light transmittance of the sheet can be increased by increasing the porosity of the included base fabric. Can be increased to such an extent that sufficient light can be taken into the cultivation of crops. In addition, in agricultural and horticultural houses, in order to prevent the temperature of crops and soil in the house from excessively rising due to near infrared rays contained in sunlight, a light shielding sheet may be used in the summer, and the removal work is not possible. Although it is a big burden, the exothermic translucent sheet of the present invention absorbs and shields near infrared rays, and has the effect of greatly reducing near infrared rays reaching crops and soil in the house. Can be reduced.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited to these.

The following evaluation was performed about the sheet | seat produced by the following Example and comparative example.
(1) Exothermic test environment: Sheet (12) prepared in Examples / Comparative Examples in a constant temperature and humidity chamber of 20 ° C. × 65% is cut into 50 cm squares and kept in a constant temperature and humidity chamber for 24 hours. After standing still above, it is installed vertically as shown in FIG. 6, and a halogen lamp (100V,
An 85 W reflex lamp type (made by Ushio Lighting Co., Ltd.) (9-2) was fixed so that the direction of the straight line connecting the center point of the lamp and the center point of the sheet overlapped in the vertical direction.
Measurement method: The halogen lamp was turned on at a voltage of 100 V for 10 minutes and then turned off. Thereafter, the temperature at the center of the sheet was measured with a contact-type surface thermometer using a thermocouple sensor.
The measurement surface is described in the following examples and comparative examples.
(2) Condensation prevention test environment: The inside size is 50cm in height x 50cm in width x 50cm in length, and has a temperature control device that can cool and cool the inside. A box-shaped structure (13) having a 20 cm square hole at one center was prepared. The sheet (12) prepared in the example and the comparative example is cut into a 30 cm square in the hole of the box structure, and the front surface of the sheet is directed to the inside of the box structure so that the inside of the box is The sheet was attached in close contact so that there was no external air flow, and the sheet was attached vertically and placed in a constant temperature and humidity room of 20 ° C. × 65%. Fix the same halogen lamp (9-2) used in the exothermic test at a position 50 cm on the back side of the sheet so that the direction of the straight line connecting the center point of the lamp and the center point of the sheet overlaps the vertical direction. did. The halogen lamp was connected to a power source (not shown) whose voltage can be adjusted steplessly.
Measurement method: With the temperature inside the box structure at 20 ° C, the halogen lamp is turned on at a voltage of 100 V, and after 1 minute, the temperature control device attached to the box structure is activated, and the box structure The temperature inside the body was adjusted to 5 ° C. When the temperature inside the box-shaped structure is stabilized at 5 ° C, the back of the sheet is observed. If no condensation occurs, the voltage supplied to the halogen lamp is reduced by 5V.
Observe the back of the sheet after a minute. This operation was repeated to lower the voltage to a minimum of 50 V and evaluated as follows.
Condensation did not occur even at 1: 50V.
2: Condensation occurred at 50 to 70V.
3: Condensation occurred at 75 to 90V.
4: Dew condensation occurred at 95-100V.
* The dew point temperature at 20 ° C x 65% is 13.2 ° C. In the state where the front side of the sheet is exposed to an atmosphere of 5 ° C, condensation occurs when the backside surface of the sheet falls below 13.2 ° C. The A sheet that can be maintained at a temperature exceeding 13.2 ° C. at a lower voltage is a sheet that is highly effective in preventing the occurrence of condensation by near infrared irradiation.
(3) Snow sliding test environment: An aluminum frame 1 (14) having a width of 60 cm and a length of 100 cm is prepared.
Four sides of the sheet (12) prepared in the comparative example were fixed and stretched. Next, a snow block 1 (15) having a width of 20 cm, a length of 20 cm, and a thickness of 5 cm is placed at the center of the front surface of the sheet, and the aluminum frame to which the sheet is fixed is inclined by 15 ° to cover the periphery. Base 1 without board or top plate
Fixed to (16). On the back side of the sheet, the same halogen lamp (9-2) as that used in the exothermic test was applied, and the direction of the straight line connecting the center point of the lamp and the center point of the sheet overlapped the vertical direction. The sheet was fixed so that the distance was 50 cm. (Refer to Fig. 8) A series of operations, including evaluation, were all performed in a cold storage room at 0 ° C. In addition, the snow blocks were placed on the sheets after the sheets were left in the cold storage for 1 hour.
Snow mass creation method: Form with no bottom on a sheet placed horizontally in a 0 ° C cold storage (inside size:
(20cm in length, 20cm in width, 30cm in depth), put 200g of fresh snow sampled outdoors at -5 ℃ into the mold, and press-mold it to a uniform thickness of 5cm. Removed.
Evaluation method: A halogen lamp is turned on at a voltage of 100 V, the state of the snow mass is observed every hour,
The time until the snow block slipped and the snow on the sheet disappeared was measured and evaluated as follows.
Within 1: 1 hour, there was no snow on the sheet.
The snow on the sheet disappeared within 2 hours after 2: 1 hours.
3: Snow remained after 2 hours.
(4) Snow melting property test environment: An aluminum frame 2 (17) having a width of 30 cm and a length of 30 cm was prepared, and the four sides of the sheet (12) prepared in the examples and comparative examples were fixed and stretched. Next, a snow block 2 (18) having a width of 10 cm, a length of 10 cm, and a thickness of 1 cm is placed in the center of the front surface of the sheet, and there is no plate or top plate covering the periphery with the aluminum frame to which the sheet is fixed. It was fixed on a horizontal base 2 (19). On the back side of the sheet, the same halogen lamp (9-2) used in the exothermic test,
The direction of the straight line connecting the center point of the lamp and the center point of the sheet overlapped in the vertical direction, and the distance between the lamp and the sheet was fixed to 20 cm. (See Fig. 9) A series of operations including evaluation was performed in a cold storage warehouse at 0 ° C. In addition, the snow blocks were placed on the sheet after the sheet was left in the cold storage warehouse for 1 hour.
Snow mass creation method: Form with no bottom on a sheet placed horizontally in a 0 ° C cold storage (inside size:
10cm in length, 10cm in width, 10cm in depth), put 10g of fresh snow sampled outdoors at -5 ℃ into the mold, and press-mold it to a uniform thickness of 1cm. Removed.
Evaluation method: A halogen lamp was lit at a voltage of 100 V, and observed every 10 minutes, and evaluated as follows.
The snow was completely melted within 1:30 minutes.
2:30 More than 60 minutes and the snow was completely melted within 60 minutes.
3: Some snow remained even after 60 minutes.
(5) Visible light transmittance
Measurement was performed using a Minolta spectrocolorimeter CM-3600d according to JIS Z8722.5.4 (Condition g).
(6) Static contact angle About the front surface of the sheet, using a contact angle meter (CA-D type, manufactured by Kyowa Science Co., Ltd.)
The static contact angle with distilled water was measured by a droplet method in a constant temperature and humidity room at 20 ° C. and 65%. The measurement was performed 30 seconds after dropping of distilled water.
(7) Ten-point average roughness Rz value (JISB601-1994)
Only the reference length is extracted in the direction of the average line from the roughness curve of the cross section of the sheet, and the sum of the average value of the altitude at the top of the mountain from the highest to the fifth and the average value of the altitude at the bottom of the valley from the deepest to the fifth The value was determined.

[Example 1]
The hot-melt kneaded product of the light-diffusing substance-containing soft vinyl chloride resin of the following formulation 1 and the hot-melt kneaded product of the tungsten oxide fine particle-containing styrene butadiene block copolymer (SBS) of the following formulation 2 are added to the mass of the vinyl chloride resin alone. 20 mass% was added, and it heat-kneaded and kneaded with the Banbury mixer, and obtained the incompatible resin mixture 1 in which the styrene butadiene block copolymer was uniformly disperse | distributed. In Formulation 1, titanium oxide particles having an average particle size of 1.0 μm were used as the light diffusing substance, and in Formulation 2, WO _2.72 having an average particle size of 80 nm was used as the tungsten oxide fine particles. This immiscible resin mixture 1 was passed through four calender rolls set at 180 ° C. to form a heat-converting resin layer film 1-1 having a thickness of 0.25 mm. On the other hand, a soft vinyl chloride resin hot-melt kneaded product from which titanium oxide particles were omitted from formulation 1 was passed through four calender rolls set at 180 ° C. to form a film 1-2 having a thickness of 0.25 mm. Next, the following base fabric 1 was inserted between the obtained film 1-1 and film 1-2, and laminated by thermocompression bonding to obtain a tarpaulin-shaped light transmitting sheet. When the heat-converting resin layer made of the film 1-1 is observed with a microscope, the styrene-butadiene block copolymer containing tungsten oxide fine particles constitutes the island component phase, and the soft vinyl chloride resin containing titanium oxide particles constitutes the sea component phase. It was. The island component content in the heat-convertible resin layer was 11.7% by volume, and the average particle size of the island component phase was 6.2 μm. Next, the surface of the heat-convertible resin layer side is smoothed by mirror surface embossing, and then a processing liquid consisting of the following composition 3 is applied to the embossed surface side using a gravure coater, dried at 120 ° C. for 3 minutes and then cooled. A 5 g / m ² fluororesin-containing antifouling layer was formed, and a light blue exothermic translucent sheet slightly turbid was obtained. Various evaluations were performed on the heat-generating translucent sheet using the surface provided with the antifouling layer as the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 1>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate ( Stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight UV absorber: benzotriazole-based 0.5 part by weight Light diffusible substance (titanium oxide particles: average particle size 1 μm) 2 parts by weight

<Formulation 2>
100 parts by mass of styrene / butadiene block copolymer (product name: Asaflex 830, manufactured by Asahi Kasei Chemicals Corporation)
Tungsten oxide fine particles (WO _2.72 : average particle diameter 80 nm) 1.5 parts by mass

<Formulation 3>
100 parts by mass of fluoroolefin vinyl ether resin (manufactured by Asahi Glass Co., Ltd., trade name: Fluorotop 1053, solid content 50% by mass)
10 parts by mass of isophorone isocyanate curing agent (manufactured by Takeda Pharmaceutical Co., Ltd., trade name: Takenate D-140N, solid content 75% by mass)
Silica (made by Tokuyama Corporation, trade name: Fine Seal X37) 5 parts by mass Methyl ethyl ketone (solvent) 100 parts by mass

(Base fabric 1)
Coarse plain weave fabric using polyester 833dtex multifilament Density Warp (warp) 18 / inch Weft (weft) 19 / inch

[Example 2]
A hot-melt kneaded product of a light-diffusible substance-containing soft vinyl chloride resin comprising a composition of the following formulation 4 and a styrene-butadiene block copolymer (SBS) containing a composite tungsten oxide fine particle comprising the composition of the following formulation 5 Was added in an amount of 20% by mass based on the mass of the vinyl chloride resin alone, followed by hot melt kneading with a Banbury mixer to obtain an incompatible resin mixture 2 in which the styrene-butadiene block copolymer was uniformly dispersed. In Formulation 4, as the light diffusing substance, titanium oxide particles having an average particle diameter of 1 μm and crosslinked polystyrene particles having an average particle diameter of 6 μm were used in combination. Further, in Formulation 5, Na _0.33 WO ₃ having an average particle diameter of 80 nm was used as the composite tungsten oxide fine particles. This incompatible resin mixture 2 was passed through four calender rolls set at 180 ° C. to form a film 2-1 for a heat-converting resin layer having a thickness of 0.25 mm. On the other hand, hot melt kneaded material of soft vinyl chloride resin from which titanium oxide particles and cross-linked polystyrene particles are omitted from formulation 4 is passed through four calendar rolls set at 180 ° C. to form a film 2-2 having a thickness of 0.25 mm. did. Next, the following base fabric 1 was inserted between the obtained film 2-1 and film 2-2 and laminated by thermocompression to obtain a tarpaulin-shaped light transmitting sheet. When the heat-converting resin layer of the obtained light-transmitting sheet is observed with a microscope, the composite tungsten oxide fine particle-containing styrene butadiene block copolymer constitutes an island component phase, and soft vinyl chloride containing titanium oxide particles and crosslinked polystyrene particles The resin constituted the sea component phase. The island component content in the heat-convertible resin layer was 10.7% by volume, and the average particle size of the island component phase was 6.2 μm. Next, the surface of the light-transmitting sheet on the heat-converting resin layer side is smoothed by mirror embossing, and then a processing liquid comprising the following composition 6 is applied to both the front and back surfaces using a gravure coater and dried at 120 ° C. for 1 minute. Upon cooling, a 5 g / m ² additive migration preventing layer was formed. Next, a processing liquid consisting of the following formulation 7 was applied onto the additive migration prevention layer on the mirror embossed side using a gravure coater, dried at 100 ° C. for 1 minute, and then cooled to adhere 1.5 g / m ² . -A protective layer is formed, and further, a processing liquid comprising the following formulation 8 is applied thereon with a gravure coater, dried at 120 ° C for 2 minutes and then cooled to form a 1.5 g / m ² photocatalyst-containing antifouling layer. As a result, a transparent pale blue exothermic translucent sheet was obtained. Various evaluations were performed on the exothermic translucent sheet with the surface provided with the antifouling layer as the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 4>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate ( Stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight UV absorber: benzotriazole-based 0.5 part by weight Light diffusible substance (titanium oxide particles: average particle size 1 μm) 1 part by weight Light diffusible substance ( Cross-linked polystyrene particles: average particle diameter 6 μm) 15 parts by mass

<Formulation 5>
100 parts by mass of styrene / butadiene block copolymer (product name: Asaflex 830, manufactured by Asahi Kasei Chemicals Corporation)
Composite tungsten oxide fine particles (Na _0.33 WO ₃ : average particle diameter 80 nm)
1.5 parts by weight

<Formulation 6>
20 parts by mass of vinylidene fluoride-tetrafluoroethylene copolymer resin (manufactured by Elf Atchem Japan Ltd., trade name: Kyner 7201)
MEK (solvent) 80 parts by mass

<Formulation 7>
Ethanol-ethyl acetate (50/50 mass ratio) solution containing 8 mass% (solid content) of an acrylic silicone resin having a silicone content of 3 mol% 100 mass parts 20% ethanol solution of methylsilicate MS51 (manufactured by Colcoat Co., Ltd.) Polysiloxane) 8 parts by mass γ-glycidoxypropyltrimethoxysilane (silane coupling agent) 1 part by mass

<Formulation 8>
Colloidal silica (manufactured by Nissan Chemical Industries, Ltd., trade name: Snowtex O) 67 parts by mass Methyltrimethoxysilane 33 parts by mass Photocatalyst: aqueous dispersion containing 10% by mass of titanium oxide
(Product name: TS-S4420, manufactured by Sumitomo Chemical Co., Ltd.) 10 parts by weight Diluting solvent (ethyl alcohol) 30 parts by weight

[Example 3]
To the stirring mixture of the light diffusible substance-containing soft vinyl chloride resin paste of the following formulation 9, 20% by mass of the hexaboride fine particle-containing vinyl ester resin stirring mixture of the following formulation 10 is added to the mass of the vinyl chloride resin alone and stirred. Then, the hexaboride fine particle-containing vinyl ester resin was uniformly dispersed to obtain an incompatible resin mixture liquid 3. In Formulation 9, interference mica particles having an average particle size of 30 μm and coated with a thin film having a multilayer structure of three layers of (TiO ₂ / SiO ₂ / TiO ₂ ) as a light diffusing substance in Formula 10 , LaB ₆ having an average particle diameter of 80 nm was used as a boride. Next, this resin mixture liquid 3 is coated on one surface of the PET film with a clearance of 2.5 mm, and heated in an electric furnace at 180 ° C. for 5 minutes to solidify the resin mixture liquid 3, and heat conversion with a PET film Film 3-1 for a conductive resin layer was molded. On the other hand, a stirred mixture of soft vinyl chloride resin paste from which the interference mica particles are omitted from Formulation 9 is coated on one surface of a PET film with a clearance of 2.5 mm, and solidified by heating at 180 ° C. for 5 minutes in an electric furnace. A film 3-2 with a PET film was molded. Between the obtained film 3-1 and film 3-2, the base fabric 1 is inserted so that the PET film faces outside, and is laminated by thermocompression bonding, and then the PET film is removed, so that both surfaces are smooth. A tarpaulin-like light transmissive sheet was obtained. When the heat-converting resin layer made of the film 3-1 is observed with a microscope, the hexaboride fine particle-containing vinyl ester resin constitutes the island component phase, and the light diffusible substance-containing soft vinyl chloride resin constitutes the sea component phase. It was. The island component content in the heat-convertible resin layer was 7.8% by volume, and the average particle size of the island component phase was 7.2 μm. Next, in the same manner as in Example 2, an additive migration preventing layer is formed on both the front and back surfaces, and an adhesive / protective layer and a photocatalyst-containing antifouling layer are further formed on the additive migration preventing layer on the heat-converting resin layer side. As a result, a pale green exothermic translucent sheet having a pearly luster was obtained. Various evaluations were performed on the exothermic translucent sheet with the surface provided with the antifouling layer as the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 9>
Emulsion polymerization polyvinyl chloride resin (degree of polymerization 1600) 100 parts by weight Di-2-ethylhexyl phthalate (plasticizer) 50 parts by weight tricresyl phosphate (plasticizer) 20 parts by weight Antimony trioxide (flame retardant) 10 parts by weight Stearic acid Zinc (stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight UV absorber: benzotriazole-based 0.5 part by weight Light diffusing substance (interference mica particles: average particle size 30 μm) 2 parts by weight

<Formulation 10>
100 parts by mass of vinyl ester resin (manufactured by Nippon Iupika Co., Ltd., trade name: Neopole 8319)
1 part by weight of curing agent (di- (4-tert-butylcyclohexyl) peroxydicarbonate)
6 boride fine particles (LaB ₆ : average particle diameter 80 nm) 1 part by mass

[Example 4]
A hot melt kneaded product of a composite tungsten oxide fine particle / hydrotalcite compound-containing styrene butadiene block copolymer (SBS) of the following formulation 12 is chlorinated into a hot melt kneaded product of the light diffusing substance-containing soft vinyl chloride resin of the formulation 11. An incompatible resin mixture 4 in which the styrene-butadiene block copolymer was uniformly dispersed was obtained by adding 17% by mass with respect to the mass of the vinyl resin alone and hot-melt-kneading with a Banbury mixer. In Formulation 11, aluminum oxide particles having an average particle size of 2 μm as a light diffusing substance, Cs _0.33 WO ₃ having an average particle size of 80 nm as composite tungsten oxide fine particles in Formulation 12, and an average particle size as a hydrotalcite compound “MIZUKALAC (trade name)” manufactured by Mizusawa Chemical Co., Ltd. having a size of 2.8 μm was used. This incompatible resin mixture 4 was passed through four calendar rolls set at 180 ° C. to form a film 4-1 for a heat-converting resin layer having a thickness of 0.25 mm. On the other hand, a soft vinyl chloride resin hot-melt kneaded product in which aluminum oxide particles were omitted from Formulation 11 was passed through four calendar rolls set at 180 ° C. to form a film 4-2 having a thickness of 0.25 mm. Next, the base fabric 1 was inserted between the obtained film 4-1 and film 4-2 and laminated by thermocompression to obtain a tarpaulin-like light transmitting sheet. When the heat-converting resin layer composed of the film 4-1 is observed with a microscope, the composite tungsten oxide fine particles / hydrotalcite compound-containing styrene-butadiene block copolymer constitutes an island component, and the aluminum oxide particle-containing soft vinyl chloride resin Constructed a sea component phase. The island component content in the heat-convertible resin layer was 10.0% by volume, and the average particle size of the island components was 6.2 μm. Next, after the surface of the light-transmitting sheet on the heat-converting resin layer side was smoothed by mirror surface embossing, an additive migration preventing layer was formed on both the front and back surfaces in the same manner as in Example 2, and further mirror surface embossing was performed. An adhesive / protective layer and a photocatalyst-containing antifouling layer were sequentially formed on the side of the additive-transfer-preventing layer to obtain a light blue exothermic translucent sheet that was slightly cloudy. Various evaluations were performed on the exothermic translucent sheet with the surface provided with the antifouling layer as the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 11>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate ( Stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight Ultraviolet absorber: benzotriazole-based 0.5 part by weight Light diffusing substance (aluminum oxide particles: average particle diameter 2 μm) 2 parts by weight

<Formulation 12>
100 parts by mass of styrene / butadiene block copolymer (product name: Asaflex 830, manufactured by Asahi Kasei Chemicals Corporation)
Composite tungsten oxide fine particles (Cs _0.33 WO ₃ : average particle diameter 80 nm)
0.7 parts by mass Hydrotalcite compound 5 parts by mass (manufactured by Mizusawa Chemical Co., Ltd., trade name: MIZUKALAC, average particle size: 2.8 μm)

[Example 5]
The hot melt kneaded product of the light diffusible substance-containing soft fluororesin of the following formulation 13 and the hot melt kneaded product of the phthalocyanine compound-containing soft vinyl chloride resin of the following formulation 14 are 10% by mass with respect to the mass of the soft fluororesin alone. In addition, hot melt kneading was performed with a Banbury mixer, and the vinyl chloride resin was uniformly dispersed to obtain an incompatible resin mixture 5. In Formulation 13, interference mica particles having an average particle diameter of 30 μm, in which the surface of mica particles is coated with a thin film having a multilayer structure of (TiO ₂ / SiO ₂ / TiO ₂ ) as a light diffusing substance in Formulation 14, As a phthalocyanine compound, Nippon Shokubai Co., Ltd .: e-color 702K (trade name) was used. This resin mixture 5 was passed through four calendar rolls set at 180 ° C. to form a heat-converting resin layer film 5-1 having a thickness of 0.25 mm. On the other hand, a soft fluorinated resin hot melt kneaded product from which the interference mica particles were omitted from formulation 13 was passed through four calendar rolls set at 180 ° C. to form a film 5-2 having a thickness of 0.25 mm. Next, the base fabric 1 is inserted between the obtained film 5-1 and film 5-2, laminated by thermocompression bonding to form a tarpaulin, and the surface of the heat-converting resin layer side made of the film 5-1 is further formed. It was smoothed by mirror surface embossing to obtain a pale green exothermic translucent sheet having a pearly luster. This heat-converting resin layer is a layer which is composed of a soft fluororesin and has a function as an antifouling layer. When the heat-converting resin layer was observed with a microscope, the phthalocyanine compound-containing soft vinyl chloride resin constituted the island component, and the interference mica particle-containing soft fluororesin constituted the sea component. The island component content relative to the entire heat-converting resin layer was 13.4% by volume, and the average particle size of the island component phase was 1.7 μm. About this exothermic translucent sheet | seat, various evaluation was performed by making the surface which laminated | stacked the film 5-1 into the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 13>
100 parts by mass of soft fluororesin (tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride terpolymer resin)
Ultraviolet absorber: 0.5 parts by weight of benzotriazole series Light diffusing substance (interference mica particles: average particle size 30 μm) 2 parts by weight

<Formulation 14>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Zinc stearate (stabilizer) 2 parts by mass Barium stearate ( Stabilizer) 2 parts by weight Phthalocyanine compound (manufactured by Nippon Shokubai Co., Ltd., trade name: e-ex color 702K)
1 part by mass

[Example 6]
The heat-melt kneaded product of the composite tungsten oxide fine particle-containing polyethylene resin of the following formulation 15 is added to the heat-melt kneaded product of the light-diffusing substance-containing soft vinyl chloride resin of the formulation 1 to 20% by mass with respect to the mass of the vinyl chloride resin alone. In addition, an incompatible resin mixture 6 in which polyethylene resin was uniformly dispersed was obtained by hot melt kneading with a Banbury mixer. In Formulation 15, Na _0.33 WO ₃ having an average particle diameter of 80 nm was used as the composite tungsten oxide fine particles. The resin mixture 6 was passed through four calender rolls set at 180 ° C. to form a heat-converting resin layer film having a thickness of 0.25 mm. This film was laminated as a heat-convertible resin layer on both sides of the base fabric 1 by thermocompression bonding to obtain a tarpaulin-like light transmitting sheet. When the heat-converting resin layer was observed with a microscope, the composite tungsten oxide fine particle-containing polyethylene resin constituted the island component phase, and the titanium oxide particle-containing soft vinyl chloride resin constituted the sea component phase. The island component content in the heat-convertible resin layer was 12.1% by volume, and the average particle size of the island component phase was 10.2 μm. Next, the surface of the heat-converting resin layer on one side is smoothed by mirror embossing, and then a processing liquid comprising Formulation 3 is applied to the embossed surface side using a gravure coater, dried at 120 ° C. for 3 minutes, and then cooled. Then, a 5 g / m ² fluororesin-containing antifouling layer was formed to obtain a slightly blue cloudy light blue exothermic translucent sheet. Various evaluations were performed on the heat-generating translucent sheet using the surface provided with the antifouling layer as the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 15>
Low density polyethylene resin (density 0.945) 100 parts by mass Composite tungsten oxide fine particles (Na _0.33 WO ₃ : average particle size 80 nm)
1 part by mass

[Example 7]
13 wt% of the composite tungsten oxide fine particle-containing silicone resin stirring mixture of the following formulation 16 is added to the stirring mixture of the light diffusing substance-containing soft vinyl chloride resin paste of the formulation 4 and the mixture is stirred. Thus, an incompatible resin mixture liquid 7 in which the composite tungsten oxide fine particle-containing silicone resin was uniformly dispersed was obtained. In compound 16, Cs _0.33 WO ₃ having an average particle diameter of 80 nm was used as the composite tungsten oxide. Next, this resin mixture liquid 7 is coated on one surface of the PET film with a clearance of 2.5 mm, and heated in an electric furnace at 180 ° C. for 5 minutes to solidify the resin mixture liquid 7, and heat conversion with a PET film Film 7-1 for a conductive resin layer was molded. On the other hand, a stirred mixture of soft vinyl chloride resin paste from which the titanium oxide particles and the crosslinked polystyrene particles were omitted from Formulation 4 was coated on one side of the PET film with a clearance of 2.5 mm and heated in an electric furnace at 180 ° C. for 5 minutes. The film 7-2 with a PET film was molded. Between the obtained film 7-1 and film 7-2, the base fabric 1 is overlapped and inserted so that the PET film is on the outside, laminated by thermocompression bonding, then the PET film is removed, and both surfaces are smooth. A tarpaulin-like light transmissive sheet was obtained. When the heat-converting resin layer made of the film 7-1 is observed with a microscope, the composite tungsten oxide fine particle-containing silicone resin constitutes the island component phase, and the soft vinyl chloride resin containing the titanium oxide particles and the crosslinked polystyrene particles is the sea. It constituted the component phase. The island component content in the heat-convertible resin layer was 6.1% by volume, and the average particle size of the island component phase was 3.4 μm. Next, in the same manner as in Example 2, an additive migration preventing layer was formed on both sides of the back, and an adhesive / protective layer and a photocatalyst-containing antifouling layer were further formed on the additive migration preventing layer on the film 7-2 side. It formed in order and the transparent light blue exothermic translucent sheet | seat of Example 7 was obtained. Various evaluations were performed on the exothermic translucent sheet with the surface provided with the antifouling layer as the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the back side was measured.
<Formulation 16>
CY52-110 (silicone resin manufactured by Toray Dow Corning Silicone Co., Ltd.)
Liquid A 50 parts by mass Liquid B 50 parts by mass Composite tungsten oxide fine particles (Cs _0.33 WO ₃ : average particle diameter 80 nm)
2.5 parts by weight

[Example 8]
The hot melt kneaded product of the tungsten oxide fine particle-containing soft vinyl chloride resin of the following formulation 17 and the hot melt kneaded product of the light diffusing substance-containing styrene butadiene block copolymer (SBS) of the following formulation 18 are added to the mass of the vinyl chloride resin alone. In addition, 40% by mass was added and heat-melt kneaded with a Banbury mixer to obtain an incompatible resin mixture 8 in which the light-diffusing substance-containing styrene butadiene block copolymer (SBS) was uniformly dispersed. In Formulation 17, WO _2.72 having an average particle size of 80 nm was used as tungsten oxide fine particles, and in Formulation 18, titanium oxide particles having an average particle size of 1 μm were used as a light diffusing substance. This incompatible resin mixture 8 was passed through four calender rolls set at 180 ° C. to form a film 8-1 for a heat-converting resin layer having a thickness of 0.25 mm. On the other hand, a soft vinyl chloride resin hot melt kneaded product from which the tungsten oxide fine particles were omitted from formulation 17 was passed through four calender rolls set at 180 ° C. to form a film 8-2 having a thickness of 0.25 mm. Next, the base fabric 1 was inserted between the obtained film 8-1 and film 8-2 and laminated by thermocompression to obtain a tarpaulin-like light transmitting sheet. When the heat-converting resin layer comprising the film 8-1 is observed with a microscope, the titanium oxide particle-containing styrene butadiene block copolymer constitutes the island component phase, and the tungsten oxide fine particle-containing soft vinyl chloride resin constitutes the sea component phase. It was. The island component content in the heat-convertible resin layer was 20.9% by volume, and the average particle size of the island component phase was 6.2 μm. Next, the surface of the heat-convertible resin layer side is smoothed by mirror surface embossing, and then the processing liquid consisting of Formulation 3 is applied to the embossed surface side using a gravure coater, dried at 120 ° C. for 3 minutes and then cooled, A 5 g / m ² fluororesin-containing antifouling layer was formed, and a light blue exothermic translucent sheet slightly turbid was obtained. Various evaluations were performed on the heat-generating translucent sheet using the surface provided with the antifouling layer as the front surface. The results are shown in Table 1. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 17>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate ( Stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight UV absorber: benzotriazole-based 0.5 part by weight Tungsten oxide fine particles (WO _2.72 : average particle size 80 nm) 0.3 part by weight

<Formulation 18>
100 parts by mass of styrene / butadiene block copolymer (product name: Asaflex 830, manufactured by Asahi Kasei Chemicals Corporation)
Light diffusing substance (titanium oxide particles: average particle diameter 1 μm) 3 parts by mass

  Each of the exothermic translucent sheets of Examples 1 to 8 has a sea-island phase structure, and either the sea component phase or the island component phase contains a near-infrared absorbing material, and the other phase (near-infrared ray). Absorbing substance-free phase) has a heat-convertible resin layer containing a light diffusing substance, can generate heat efficiently by near-infrared irradiation, can prevent condensation, and has excellent snow melting properties. In addition, the sheet showed high visible light transmittance. The static contact angle with water on the front side surface of these sheets satisfies 15 to 50 ° or 80 to 110 °, respectively. In the evaluation of snow sliding performance, the snow blocks completely slip within 1 hour in all sheets. It was falling.

[Comparative Example 1]
Instead of the film 1-1 molded from the incompatible resin mixture 1, a film ratio of 1-1. A colorless and transparent sheet was prepared in the same manner as in Example 1 except that was used. This sheet was subjected to various evaluations using the side on which the antifouling layer was formed as the front surface. The results are shown in Table 2. For the exothermic test, the surface temperature on the front side was measured.

  The sheet of Comparative Example 1 has a film ratio of 1-1, which does not have a sea-island phase structure, and contains neither a near-infrared absorbing material nor a light diffusing material. The sheet was inferior in snow-sliding and snow melting properties.

[Comparative Example 2]
Instead of the film 1-1 molded from the immiscible resin mixture 1, the film ratio 2-1 of 0.25 mm thickness molded from the hot melt kneaded material of the light diffusible substance-containing soft vinyl chloride resin of Formulation 1 is used. A milky white sheet was prepared in the same manner as in Example 1 except that. This sheet was subjected to various evaluations using the side on which the antifouling layer was formed as the front surface. The results are shown in Table 2. For the exothermic test, the surface temperature on the front side was measured.

  The sheet of Comparative Example 2 has a film ratio of 2-1 and does not have a sea-island phase structure and does not contain a near-infrared absorbing material. Therefore, compared with Example 1, heat generation, anti-condensation prevention, and snow sliding properties are achieved. And a sheet having poor snow melting properties. Moreover, since the film ratio 2-1 did not have a sea-island phase structure and contained a light diffusing substance as a whole, the visible light transmittance was inferior to that of Comparative Example 1.

[Comparative Example 3]
Instead of the film 1-1 molded from the immiscible resin mixture 1, a film ratio 3-1 of 0.25 mm in thickness molded from a hot-melt kneaded product of tungsten oxide fine particle-containing soft vinyl chloride resin of the following formulation 19 A transparent blue sheet was prepared in the same manner as in Example 1 except that it was used. This sheet was subjected to various evaluations using the side on which the antifouling layer was formed as the front surface. The results are shown in Table 2. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 19>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate ( Stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight UV absorber: benzotriazole-based 0.5 part by weight Tungsten oxide fine particles (WO _2.72 : average particle size 80 nm) 0.3 part by weight

  The sheet of Comparative Example 3 had a layer having a film ratio of 3-1 containing tungsten oxide fine particles as a near infrared absorbing material, and the content of tungsten oxide fine particles per area was the same as in Example 1. However, since the film ratio 3-1 does not have a sea-island phase structure and does not contain a light diffusing substance, it cannot absorb near infrared rays sufficiently, and compared with Example 1, it is exothermic and prevents condensation. The inferiority was also poor, and the snow-sliding and melting properties were also inferior. Moreover, since it did not have a sea-island phase structure and the tungsten oxide fine particles were dispersed throughout, the visible light transmittance was also inferior.

[Comparative Example 4]
A sheet with a slightly cloudy hue was prepared in the same manner as in Example 1 except that the tungsten oxide fine particles were omitted from Formulation 2. This sheet was subjected to various evaluations using the side on which the antifouling layer was formed as the front surface. The results are shown in Table 2. For the exothermic test, the surface temperature on the front side was measured.

  The sheet of Comparative Example 4 has a sea-island phase layer and contains a light diffusing substance in the sea component phase, but does not contain a near-infrared absorbing substance in the island component phase, so it absorbs near-infrared rays efficiently. As compared with Example 1, the heat generation, the prevention of condensation, snow sliding and snow melting were inferior.

[Comparative Example 5]
Instead of the film 1-1 molded from the incompatible resin mixture 1, a film ratio of 0.25 mm thick molded from a hot-melt kneaded product of tungsten oxide fine particle-containing soft vinyl chloride resin comprising the composition of the following formulation 20 A tarpaulin-like sheet was obtained in the same manner as in Example 1 except that 5-1 was used. After smoothing the surface of this sheet on which the film ratio 5-1 was laminated by mirror embossing, an additive migration preventing layer was formed on both the front and back surfaces in the same manner as in Example 2, and the film ratio 5-1 side was further increased. A transparent blue sheet was formed by forming an adhesive / protective layer and a photocatalyst-containing antifouling layer in this order on the additive migration prevention layer. About this sheet | seat, various evaluation was performed by making into the front surface the surface which provided the photocatalyst containing antifouling layer. The results are shown in Table 2. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 20>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate ( Stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight UV absorber: benzotriazole-based 0.5 part by weight Tungsten oxide fine particles (WO _2.72 : average particle size 80 nm) 1 part by weight

  The sheet of Comparative Example 5 contained tungsten oxide fine particles as a near-infrared absorbing material in the layer having a film ratio of 5-1, and the content of tungsten oxide fine particles per area was 3.8 times that of Example 1. However, since the layer composed of the film ratio 5-1 does not have a sea-island phase structure and does not contain a light diffusing substance, it cannot absorb near infrared rays efficiently, and heat generation, dew condensation prevention, The snow-sliding property and snow-melting property were similar to those of Example 1, and further, the visible light transmittance was greatly inferior because it did not have a sea-island phase structure.

[Comparative Example 6]
Instead of the film 1-1 molded from the immiscible resin mixture 1, a film ratio 6-1 having a thickness of 0.25 mm molded from a hot-melt kneaded product of the soft vinyl chloride resin of Formulation 19 was used, and an antifouling layer was formed. A sheet was prepared in the same manner as in Example 1 except that it was not provided. The surface of this sheet on which the film ratio 6-1 was laminated was smoothed by mirror embossing to produce a transparent blue sheet. This sheet was subjected to various evaluations using a surface smoothed by mirror surface embossing as a front surface. The results are shown in Table 2. For the exothermic test, the surface temperature on the front side was measured.

  The sheet of Comparative Example 6 has a configuration in which the antifouling layer is omitted from Comparative Example 3. Similar to Comparative Example 3, the sheet contains tungsten oxide fine particles as a near-infrared absorbing material, and the content of tungsten oxide fine particles per area However, since the layer composed of the film ratio 6-1 does not have a sea-island phase structure, it cannot efficiently absorb near-infrared rays, and heat generation, prevention of condensation and The snow melting property was inferior. In addition, since there was no antifouling layer and the static contact angle with respect to water was 68 °, in the evaluation of snow sliding performance, snow remained even after 2 hours, and the results were inferior to Comparative Example 3. there were.

[Comparative Example 7]
Instead of the film 1-1 molded from the incompatible resin mixture 1, a film ratio 7-1 having a thickness of 0.25 mm molded from a hot-melt kneaded product of a soft vinyl chloride resin having the following composition 21 was used. A sheet was prepared in the same manner as in Example 1 to prepare a cloudy blue sheet. The sheet was subjected to various evaluations using the surface on which the antifouling layer was formed as the front surface. The results are shown in Table 2. For the exothermic test, the surface temperature on the front side was measured.
<Formulation 21>
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 10 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate ( Stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight Ultraviolet absorber: benzotriazole-based 0.5 part by weight Light diffusing substance (titanium oxide particles: average particle size 1 μm) 1.8 parts by weight Tungsten oxide _Fine particles (WO _2.72 : average particle size 80 nm) 0.3 parts by mass

  In the sheet of Comparative Example 7, the layer composed of the film ratio 7-1 contained the light diffusing substance and the tungsten oxide fine particles, and the content per area was the same as in Example 1, but the film ratio 7- Since the layer consisting of 1 does not have a sea-island phase structure, it cannot absorb near infrared rays efficiently, has poor heat generation, prevention of condensation and snow melting, and has poor snow sliding and snow melting. Moreover, since it did not have a sea-island phase structure and the light diffusing substance and the tungsten oxide fine particles were dispersed throughout, the visible light transmittance was also lower than that in Example 1.

  The exothermic translucent sheet of the present invention has high transmissivity in the visible light region, and also has a exothermic property that efficiently absorbs near-infrared rays and raises the temperature efficiently. Therefore, the exothermic translucent sheet of the present invention is used. By irradiating the heat-generating translucent sheet with near-infrared rays, the near-infrared rays are converted into thermal energy to prevent internal condensation, and the snow condition on the roof is sequentially controlled. Since a possible translucent membrane roof structure can be obtained, it is suitably used for amusement spaces, event spaces, rainy weather fields, tent warehouses, event tents, agricultural horticultural house membrane structures, and their lighting structures. be able to.

1: exothermic translucent sheet 2: heat-convertible resin layer 3: island component phase 3-1: island component phase containing near-infrared absorbing material 3-2: island component containing particles made of light diffusing material Phase 4: Sea component phase 4-1: Sea component phase containing near-infrared absorbing material 4-2: Sea component phase containing particles made of light diffusing material 5: Antifouling layer 6: Sea island phase structure Resin layer 7: Base fabric 8: Exothermic translucent roof structure 8-1: Tent warehouse 8-2: Tents for events 8-3: Agricultural and horticultural house 9: Near infrared irradiation device 9-1: Halogen heater 9-2: Halogen lamp 10: Main building 11: Eaves 12: Sheet 13 prepared in the embodiment / comparative example 13: Box structure 14: Aluminum frame 1
15: Snow mass 1
16: Mount 1
17: Aluminum frame 2
18: Snow mass 2
19: Mount 2

Claims (11)

  A light transmissive sheet having a heat-convertible resin layer, wherein the heat-convertible resin layer has a sea-island phase structure made of an incompatible mixture of a synthetic resin blend, and in the sea-island phase structure, a sea component phase or an island Any one of the component phases is a phase containing at least one kind of near-infrared absorbing substance selected from near-infrared absorbing inorganic fine particles and near-infrared absorbing organic dyes, and the other phase is An exothermic translucent sheet comprising particles of a light diffusing substance.   The exothermic translucent sheet according to claim 1, wherein an antifouling layer is provided on the outermost layer of the light transmissive sheet.   The snow melting sheet according to claim 2, wherein a static contact angle with water on a surface of the antifouling layer is 15 to 50 °.   The snow melting sheet according to claim 2, wherein a static contact angle with water on the surface of the antifouling layer is 80 to 110 °. The near-infrared absorbing inorganic compound particles, tungsten oxide, the composite tungsten oxide, represented by the hexaboride (general formula XB _6, X is Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb 1 or 2 elements selected from Dy, Ho, Er, Tm, Yb, Lu, Zr, Ba, Sr and Ca), and one or more selected from hydrotalcites 5. The exothermic translucent sheet according to any one of 4 to 4.   The near-infrared absorptive organic dye contains at least one selected from phthalocyanine compounds, naphtholquinone compounds, imonium compounds, anthraquinone compounds, aminium compounds, and nickel-thiol complex compounds. 5. The exothermic translucent sheet according to any one of 4 to 4.   The heat generation according to any one of claims 1 to 6, wherein the particles made of the light diffusing substance include at least one selected from ceramic particles, interference mica particles, glass beads, glass particles, resin beads, and resin particles. Translucent sheet.   The exothermic translucent sheet according to any one of claims 1 to 7, wherein the light transmissive sheet is a laminate including a coarse knitted fabric as a base fabric.   A film structure having a light transmissive sheet having a heat-converting resin layer as a roofing material, wherein the heat-converting resin layer has a sea-island phase structure, and in the sea-island phase structure, a sea component phase or an island component phase Any one of the phases contains at least one near-infrared absorbing substance selected from near-infrared absorbing inorganic fine particles and near-infrared absorbing organic dyes, and the other phase is a light diffusing substance. An exothermic translucent membrane roof structure characterized in that, when the light transmitting sheet is irradiated with near infrared rays, the near infrared rays are converted into thermal energy.   The exothermic translucent membrane roof structure according to claim 9, wherein an antifouling layer is provided on the outermost layer of the light transmissive sheet.   The exothermic translucent membrane roof structure according to claim 9 or 10, wherein the light transmissive sheet is a laminate including a coarse knitted fabric as a base fabric.