JP2014040035A - Heat control sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat control sheet which has a high degree of freedom of color tone, has no adverse influence on a surrounding landscape, transmits heat rays in the winter season, and shields the heat rays in the summer season.SOLUTION: A heat control sheet is a flexible sheet which includes a near infrared rays variable scattering layer, in which the near infrared rays variable scattering layer is constituted of a transparent matrix resin composed of a soft polyvinyl chloride resin composition, transparent particles dispersed and included in the transparent matrix resin and having an average particle diameter of 1-20 μm, and a near infrared permeable colorant, and in which the transparent particle is at least one selected from a crosslinked acrylic particle, a crosslinked polystyrene particle, a crosslinked acrylic-polystyrene copolymer particle, and a glass particle, and a difference between a refractive index of the transparent matrix resin and that of the transparent particle is 0.01 or less at a flexible sheet temperature of 0-10°C and is 0.03 or more and 0.06 or less at a flexible sheet temperature of 60-70°C.

Description

  The present invention relates to a heat controllable sheet that exhibits heat ray permeability capable of incorporating near infrared rays at low temperatures and exhibits heat ray shielding properties by scattering near infrared rays at high temperatures. More specifically, the present invention has a high degree of freedom in hue, can transmit near infrared rays in winter, can incorporate solar heat into the film structure, and scatters near infrared rays contained in sunlight in summer. Therefore, it is possible to suppress the temperature rise inside the membrane structure constituted by this sheet, and there is little adverse effect on the surrounding landscape due to the scattering of visible light, especially tent warehouses, large event tents, agricultural and horticultural houses Further, the present invention relates to a heat controllable sheet that can be suitably used for an awning tent, an awning monument, a decorative tent, a blind, a sheet shutter, and the like.

  Vinyl chloride resin is relatively inexpensive and is a highly versatile resin that can impart various properties such as weather resistance, heat resistance, cold resistance, and flame retardancy depending on the composition. In particular, sheets using soft vinyl chloride resin with plasticizer added to vinyl chloride resin can be fused and sewn with a high-frequency welder or hot air, are easy to assemble and install, and have a high degree of freedom in design such as hue and structure. For these reasons, it is used in a wide range of fields such as tent warehouses, large tents for events, agricultural and horticultural houses, awning tents, awning monuments, decorative tents, blinds and seat shutters. However, the conventional sheet has a large transmission or absorption with respect to the near infrared rays contained in the solar radiation, and the near infrared rays transmitted from the front surface side of the sheet directly warm the space on the back side, and the absorbed near infrared rays. Increases the temperature of the sheet and is released as radiant heat not only from the front side of the sheet but also from the back side. For example, when used in a tent warehouse, the temperature inside the tent warehouse is subject to strong summer sunlight. It became extremely high and it was difficult for people to work for a long time. Further, the temperature of the sheet illuminated by sunlight may exceed 70 ° C., and there is a possibility that the fusion-sewn part is softened and broken in an application where a high tension is applied like a tent warehouse. When used in an awning tent, the actual situation is that although there is an effect of blocking the sun to prevent glare and reducing ultraviolet rays, there is almost no effect on the cooling effect. In the case of a tent warehouse, as a countermeasure, it is possible to lower the internal temperature if cooling is used like a normal building, but the cooling efficiency becomes very bad, and energy costs and the associated environmental burden are considered. It was not a preferable method.

  In such a sheet, by using a white sheet containing an inorganic white pigment such as titanium oxide, it is possible to scatter near-infrared rays contained in solar radiation and prevent its transmission, and to suppress the temperature rise of the sheet itself. Are known. However, in order to obtain a sufficient effect using a normal white pigment, it is necessary to add a large amount, so there is a problem that the hue of the sheet is limited to white systems such as white, ivory, and light gray. In addition, these white pigments strongly scatter not only near infrared rays but also visible rays, so that when they are used outdoors, the reflection of sunlight is dazzling and there is a problem in landscape. On the other hand, the inventor has a sheet having a heat shielding layer containing amorphous inorganic compound particles having a refractive index of 1.8 or more, a particle size distribution of 0.3 to 3.0 μm, and an aspect ratio of 1.0 to 3.0. Proposed. (Refer patent document 1) Since the amorphous inorganic compound particle contained in the heat-shielding layer of patent document 1 selectively scatters near-infrared rays, the sheet containing this is a surface under hot weather as compared with a conventional sheet. The temperature was low by 10 to 15 ° C., and a high level of heat shielding was developed. These amorphous inorganic compound particles strongly scatter near-infrared rays, but the scattering of visible light is somewhat weak, so the glare caused by the reflection of sunlight can be reduced somewhat, and a chromatic pigment can be added to the sheet. It was also possible to color. However, since the influence of the amorphous inorganic compound particles on the hue is unavoidable, there is a restriction that even if a pigment having a hue close to the primary color is added, a pastel tone is obtained and a highly saturated film material cannot be obtained. In addition, in order to sufficiently suppress glare, it is necessary to make the hue low in brightness, but if a dark pigment is included for that purpose, near infrared rays are caused by carbon black generally contained in the dark pigment. There is a problem that the heat shielding property is lowered by increasing the temperature of the sheet by being absorbed and releasing the heat as radiant heat from the back side of the sheet.

  In order to obtain heat insulation and color freely, for example, a method using a chromatic or black composite pigment obtained by coating a white pigment with a near-infrared reflective and / or near-infrared transparent pigment (see, for example, Patent Document 2) ), And a method of forming a near-infrared transmissive colored layer on the near-infrared reflective layer (for example, see Patent Document 3). If these methods are applied to a sheet, a cooling effect in summer can be obtained without limitation of hue, and it can contribute to an improvement in cooling efficiency inside a structure such as a tent warehouse composed of the sheet. However, in the winter, near infrared rays contained in solar radiation could not be taken into the interior, and there was a problem that the heating efficiency was rather lowered.

  In a sheet containing a transparent thermoplastic resin and transparent particles dispersed in the thermoplastic resin, the refractive index of the thermoplastic resin and the particles is close at room temperature, and the refractive index is different at high temperatures. Sheets for window materials that scatter light and exhibit a reversible dimming effect have also been proposed. (For example, refer to Patent Document 4) This sheet can be used by laminating it on a window glass or a transparent plastic plate, so that sunlight and light can be taken in when the sheet temperature is about 20 ° C., and 50 At about 0 ° C., the sunlight can be scattered to adjust the brightness of transmitted light, and the heat shielding property can be shown by blocking sunlight. However, since the thermoplastic resin is transparent, the temperature of the sheet only rises to about 50 ° C., and the difference in refractive index between the thermoplastic resin and the particles is not sufficient, so that the obtained heat shielding property cannot be said to be sufficient. Met. Further, when this sheet is used for a structure such as a tent warehouse, sunlight is scattered to the outside at a high temperature, which has a problem in landscape.

  As described above, in the winter season, it has near-infrared transmission and heat ray permeability that incorporates solar heat inside the film structure, and in the summer, the near-infrared ray contained in sunlight is scattered to show heat ray shielding. No sheet has been proposed so far, which has no limitation in hue and no landscape problems due to light scattering.

JP 2007-055177 A JP 2002-249676 A JP 2004-314596 A JP 2009-275133 A

  The present invention has a high degree of freedom in hue, shows heat ray permeability in winter, can incorporate solar heat into the membrane structure, and in the summer, near infrared light contained in sunlight without any landscape problems due to light scattering It is intended to provide a heat-controllable sheet that exhibits heat-ray shielding properties by scattering and can suppress a temperature rise inside the membrane structure constituted by this sheet.

  As a result of intensive studies to solve the above problems, the present inventor has found that a transparent matrix resin having a large temperature dependency of the refractive index, transparent particles having a small temperature dependency of the refractive index, a near-infrared transmitting colorant, The inventors have conceived that the above problem can be solved by combining the above. Furthermore, the soft polyvinyl chloride resin composition is easy to adjust the refractive index by adjusting the amount and type of plasticizer, and the temperature dependence of the refractive index is relatively large. The present inventors have found that it is an optimal transparent matrix resin and have completed the present invention.

  That is, the heat-controllable sheet of the present invention is a flexible sheet including a near-infrared variable scattering layer, wherein the near-infrared variable scattering layer comprises a transparent matrix resin made of a soft polyvinyl chloride resin composition, and the transparent matrix. It is composed of transparent particles having an average particle diameter of 1 to 20 μm dispersed and contained in the resin, and a near-infrared transparent colorant, and the transparent particles are crosslinked acrylic particles, crosslinked polystyrene particles, crosslinked acrylic-polystyrene copolymer particles, And the difference between the refractive index of the transparent matrix resin (based on the JISK7142A method) and the refractive index of the transparent particle (based on the JISK7142B method) is the flexible sheet temperature. It has 0.01 or less at 0 to 10 ° C. and a flexible sheet temperature of 0.03 or more and 0.06 or less at 60 to 70 ° C. It is characterized in.

The heat-controllable sheet of the present invention exhibits heat ray permeability when the flexible sheet temperature is 0 to 10 ° C, and exhibits heat ray shielding property when the flexible sheet temperature is 60 to 70 ° C. It is preferable.

  In the heat-controllable sheet of the present invention, in the near-infrared variable scattering layer, the content of the transparent particles is preferably 30 to 150 with respect to the matrix resin 100 in a volume ratio.

  In the heat-controllable sheet of the present invention, the near-infrared transparent colorant is a perylene, perinone, phthalocyanine, carbonium, anthraquinone, quinophthalone, azo, azomethine, or quinacridone organic pigment or organic dye. It is preferable that the near-infrared variable scattering layer contains 0.05 to 5 parts by mass of the near-infrared transparent colorant with respect to 100 parts by mass of the transparent matrix resin. .

  In the heat-controllable sheet of the present invention, it is preferable that the soft polyvinyl chloride resin composition contains 40 to 150 parts by mass of a plasticizer with respect to 100 parts by mass of the polyvinyl chloride resin.

  In the heat controllable sheet of the present invention, the flexible sheet is preferably a laminate including a fibrous knitted fabric as a base fabric.

  In the heat-controllable sheet of the present invention, it is preferable that the flexible sheet has at least one antifouling layer as the outermost layer.

  In the thermally controllable sheet of the present invention, the transmittance of near infrared rays having a wavelength of 780 to 1600 nm (based on JISR3106) is 30% or more at a sheet temperature of 0 to 10 ° C, and 15% or less at 60 to 70 ° C. Is preferred.

  According to the present invention, a heat-controllable sheet that exhibits heat ray permeability that allows solar heat to be taken into the membrane structure in the winter, and that exhibits heat ray shielding that scatters and shields solar heat in the summer, is limited in hue. Can be provided without. In particular, a sheet containing a fibrous knitted fabric as a base fabric can be suitably used for a tent warehouse, a large event tent, an agricultural or horticultural house, a awning tent, a awning monument, a decorative tent, a blind, a sheet shutter, and the like.

The figure which shows an example of the cross section of the heat controllable sheet of this invention The figure which shows an example of the cross section of the heat controllable sheet of this invention The figure which shows the small tent used for evaluation of heat ray permeability and heat ray shielding in an example and a comparative example.

  The heat-controllable sheet of the present invention is a flexible sheet including a near-infrared variable scattering layer, and the form thereof is a resin sheet (resin film) or a waterproof sheet such as tarpaulin or canvas. Among these, the resin sheet can be manufactured by a calendar molding method, a T-die extrusion method, or a casting method, and may be a single near-infrared variable scattering layer or a plurality of resin layers including a near-infrared variable scattering layer. The laminated body which consists of may be sufficient. Tarpaulins, canvases and other waterproof sheets are laminates comprising a near-infrared variable scattering layer and a base fabric made of a fibrous knitted fabric, and the near-infrared variable scattering layer may be formed only on one surface of the base fabric. It may be formed on both sides. When the near-infrared variable scattering layer is formed only on one surface of the base fabric, a resin layer other than the near-infrared variable scattering layer may be formed on the other surface side of the base fabric. The canvas can be produced by dipping using paste sol (double-sided processing on fibrous knitted fabric), coating (single-sided processing or double-sided processing on fibrous knitted fabric), and the like. Tarpaulin is a method of laminating a resin film or resin sheet molded by a calendar molding method, a T-die extrusion method or a casting method with an adhesive layer on one or both sides of a fibrous knitted fabric, or a coarse fibrous knitting. It can be manufactured by a method of laminating by heat lamination on both sides of a woven fabric through a void space, and can also be carried out by a combination of dipping or coating and resin film lamination.

  The near-infrared variable scattering layer of the present invention comprises a transparent matrix resin comprising a soft polyvinyl chloride resin composition, transparent particles having an average particle diameter of 1 to 20 μm dispersed in the transparent matrix resin, a near-infrared transparent colorant, Is included as an essential component. The transparent matrix resin and the transparent particles have the same refractive index at a low temperature of 0 to 10 ° C., specifically, the refractive index difference at 0 to 10 ° C. (589 nm) is 0.01 or less. As a result, in winter, when the seat temperature is low, near infrared rays contained in sunlight can be taken in and heat ray permeability can be expressed. In addition, there is a difference in the temperature dependence of both refractive indexes, and the refractive index difference is 0.03 or more and 0.06 or less at a high temperature of 60 to 70 ° C., so that the sheet temperature is high in summer. It can scatter near-infrared rays contained in sunlight and develop heat ray shielding properties. Furthermore, by coloring with a near-infrared transmissive colorant, near-infrared light can be taken in in the winter without any restrictions on hue, and the influence on the surrounding landscape due to scattering of visible light in the summer can be suppressed.

  In the present invention, the soft polyvinyl chloride resin composition constituting the transparent matrix resin is a composition containing at least a polyvinyl chloride resin and a plasticizer. When the soft polyvinyl chloride resin composition contains a plasticizer, not only gives flexibility to the resulting sheet, but also adjusts the refractive index of the transparent matrix resin according to the type and amount of the plasticizer to be added. The difference in refractive index from the transparent particles at 0 ° C. can be made 0.01 or less. Moreover, the glass transition temperature of a soft polyvinyl chloride resin composition is adjusted by including a plasticizer, and the refractive index change width of the transparent matrix resin from a low temperature range of 0 to 10 ° C. to a high temperature range of 60 to 70 ° C. The refractive index difference with the transparent particles at a high temperature of 60 to 70 ° C. can be 0.03 or more. Here, the temperature dependence of the refractive index of the resin is generally small below the glass transition temperature and increases when the glass transition temperature is exceeded. Therefore, the refractive index from the low temperature range of 0 to 10 ° C. to the high temperature range of 60 to 70 ° C. In order to increase the change width, it is preferable to lower the glass transition temperature of the soft polyvinyl chloride resin composition below those temperature ranges, specifically, it is preferably less than −10 ° C., −20 ° C. More preferably, it is less.

  As the polyvinyl chloride resin that can be used in the soft polyvinyl chloride resin composition of the present invention, the number average molecular weight P obtained by emulsion polymerization P = 700-3800, preferably 1000-2000 paste vinyl chloride resin, suspension In addition to a straight vinyl chloride resin having a number average molecular weight P of 700 to 3800, preferably 1000 to 2000, obtained by polymerization, a vinyl chloride copolymer resin having a number average molecular weight P of 700 to 3800, preferably 1000 to 2000 ( A copolymerization component includes 2-30 mass%). Specific examples of the vinyl chloride copolymer resin include vinyl chloride-ethylene copolymer resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinylidene chloride copolymer resin, vinyl chloride-acrylic acid copolymer resin. And vinyl chloride-urethane copolymer resin.

Examples of the plasticizer that can be used in the soft polyvinyl chloride resin composition of the present invention include phthalate ester plasticizers (di-2-ethylhexyl phthalate, diisononyl phthalate, dinormal hexyl phthalate, diallyl phthalate, etc. ), Fatty acid ester plasticizers (di-2-ethylhexyl adipate, di-2-ethylhexyl sebacate, etc.), phosphate plasticizers (tricresyl phosphate, triphenyl phosphate, cresylphenyl phosphate), polyester Plasticizers (adipic acid polyester, phthalic polyester, etc.), sulfonate ester plasticizers, citrate ester plasticizers, trimellitic ester plasticizers, acrylic polymer plasticizers, cyclohexanedicarboxylic ester plasticizers , Ethylene-vinyl acetate-carbon monoxide Coalescence, ethylene - acrylic ester - carbon monoxide copolymer,
One or two or more functional acrylate monomers (tripropylene glycol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, etc.) can be selected and used. Depending on the type and amount of plasticizer used, the refractive index of the soft polyvinyl chloride resin composition at 0 to 10 ° C. and the range of change in the refractive index from the low temperature range of 0 to 10 ° C. to the high temperature range of 60 to 70 ° C. And the flexibility and resin strength of the near-infrared variable scattering layer are adjusted. In the soft polyvinyl chloride resin composition, the plasticizer is preferably 40 to 150 parts by mass, and more preferably 50 to 120 parts by mass with respect to 100 parts by mass of the polyvinyl chloride resin. When the plasticizer is less than 40 parts by mass, the flexibility of the obtained heat-controllable sheet may be insufficient, and the refractive index change width from the low temperature range of 0 to 10 ° C to the high temperature range of 60 to 70 ° C becomes small. The heat ray shielding property at a high temperature of 60 to 70 ° C. may be insufficient. On the other hand, when the plasticizer exceeds 150 parts by mass, the heat resistance strength of the near-infrared variable scattering layer decreases, and when a structure having a heat-sealed sewn part is formed using this sheet, the heat-resistant durability of the sewn part is as follows. May not be obtained. Further, when a large amount of plasticizer is added, the plasticizer tends to migrate to the sheet surface after the sheet is formed, and dirt may adhere to the migrated plasticizer, thereby impairing the sheet appearance.

  In the present invention, the soft polyvinyl chloride resin composition may contain other conventionally known additives as required, as long as the object of the present invention is not impaired. Examples of the additive included include a stabilizer, an ultraviolet absorber, an antioxidant, an antistatic agent, a flame retardant, an adhesive, a crosslinking agent, a lubricant, a processing aid, an antibacterial agent, an antifungal agent, and a filler. .

  In the near-infrared variable scattering layer of the present invention, the transparent particles dispersed in the soft polyvinyl chloride resin composition have little absorption with respect to light from visible light to near-infrared (wavelength 380 to 1600 nm) and 10 ° C. (wavelength 589 nm) has a refractive index of 1.49 to 1.54, and the temperature dependence of the refractive index is lower than that of the soft polyvinyl chloride resin composition in the temperature range of 0 to 70 ° C., and the soft polyvinyl chloride resin composition It is preferable that the resin is not melted or deformed by heat when it is molded and does not swell due to absorption of the plasticizer. In the present invention, one or more kinds selected from crosslinked acrylic particles, crosslinked polystyrene particles, crosslinked acrylic-polystyrene copolymer particles, and glass particles are used as the transparent particles having such characteristics. The use of particles made of acrylic resin, polystyrene resin, and acrylic-polystyrene copolymer resin is because these resins are excellent in transparency and the refractive index is relatively close to that of polyvinyl chloride resin. This is because the refractive index at low temperature of the resin composition can be easily approximated and the affinity to the polyvinyl chloride resin is excellent. Further, the reason for being limited to the crosslinked particles is to prevent melting and deformation of the particles due to heat when the near-infrared variable scattering layer is molded, and to suppress the absorption of the plasticizer. Since the refractive index of glass varies greatly depending on the composition, when glass particles are used, it is necessary to select and use a glass having a refractive index in the range of 1.49 to 1.54. Examples include lime glass. If the refractive index of the transparent particles is less than 1.49, a large amount of low refractive index plasticizer may be added in order to adjust the refractive index at the low temperature of the soft polyvinyl chloride resin composition to the same level as the transparent particles. It becomes necessary, and the heat resistance strength of the near-infrared variable scattering layer is lowered, and when the heat-controllable sheet is heat-sealed and sewn, the durability of the sewn part may be impaired. On the other hand, if the refractive index exceeds 1.54, it may be difficult to adjust the refractive index at low temperature to the same level as the transparent particles in the combination of the polyvinyl chloride resin and the plasticizer. The glass transition temperature of the composition becomes high, and the refractive index difference at a high temperature of 60 to 70 ° C. may become insufficient. Also,

  The shape of the transparent particles is not particularly limited, and may be spherical particles, distorted spheres, meteorite shapes, rugby ball shapes, or irregular particles obtained by pulverizing large chunks. The average particle size of the transparent particles is preferably 1 to 20 μm and more preferably 3 to 15 μm. When the average particle diameter is less than 1 μm, near infrared light scattering at a high temperature of 60 to 70 ° C. may be insufficient. When the average particle diameter exceeds 20 μm, the wavelength dependence of light scattering (short wavelength light scattering is large and long wavelength light scattering is small), and an iris pattern is generated in the visible light region of 380 to 780 nm. And the external appearance of a heat controllable sheet may be impaired. In addition, near infrared rays (780 nm to 1600 nm) have a longer wavelength than visible light, so that the scattering becomes smaller and the heat ray shielding property may be lowered. The content of the transparent particles in the near-infrared variable scattering layer is preferably 30 to 150, preferably 40 to 100, in terms of volume ratio, with respect to the transparent matrix resin (soft polyvinyl chloride resin composition) 100. It is more preferable. If the transparent particles are less than 30, heat ray shielding at a high temperature of 60 to 70 ° C. may not be sufficiently obtained. On the other hand, if it exceeds 150, the workability in forming the near-infrared variable scattering layer may be impaired, and further, the resin strength of the formed near-infrared variable scattering layer is lowered, and the durability of the obtained heat-controllable sheet May be damaged.

  In the near-infrared tunable scattering layer of the present invention, as the near-infrared transmissive colorant, pigments and dyes that absorb and reflect in the near-infrared region having a wavelength of 780 to 1600 nm are preferable. For example, perylene-based, perinone-based, phthalocyanine-based, Organic pigments and organic dyes such as carbonium, anthraquinone, quinophthalone, azo (monoazo, disazo, condensed disazo, etc.), azomethine, quinacridone, etc. are exemplified, and one or more of these can be selected. It is preferable to be used. It is preferable that the addition amount of the near-infrared transmitting colorant is 0.05 to 5 parts by mass with respect to 100 parts by mass of the transparent matrix resin (soft polyvinyl chloride resin composition). By including the near-infrared transmissive colorant in this range, it is possible to impart an arbitrary hue in the visible light region visible to the human eye without hindering the transmission and scattering of light in the near-infrared region. For this reason, when sunlight is scattered due to a difference in refractive index between the transparent matrix resin and the transparent particles at high temperatures, the light in the near-infrared region is scattered while the light scattering in the visible region is suppressed. The glare felt by the eyes can be suppressed. In addition, these colorants do not absorb the near infrared region having a wavelength of 780 to 1600 nm at all, but have absorption in a part of the near infrared region. When exposed to light, the temperature of the near-infrared variable scattering layer can be increased moderately. As the temperature rises, the refractive index of the transparent matrix resin gradually decreases, and as a result, the difference in refractive index from the transparent particles gradually increases, so that the heat ray shielding property at high temperatures is continuously changed from the heat ray permeability at low temperatures. The characteristic changes. Even when exposed to sunlight, the temperature of the near-infrared variable scattering layer does not rise endlessly, the rate of increase becomes slower as the near-infrared scattering increases, the thermal energy radiated from the thermal control sheet, In consideration of cooling by surrounding air, it is stable at 60 to 70 ° C. even in the midsummer sun, and the temperature does not increase excessively. Moreover, since the influence of cooling by air becomes large in winter, the sheet temperature remains at a maximum of about 30 to 40 ° C. even in fine weather, and near infrared rays can be appropriately transmitted. Here, when the addition amount of the near-infrared transmitting colorant is less than 0.05 parts by mass with respect to 100 parts by mass of the transparent matrix resin, the coloring is weak, and sunlight is scattered at a high temperature, which causes a problem on the landscape. In some cases, the temperature increase rate of the near-infrared variable scattering layer is reduced, and the temperature of the internal space of the structure may be increased before the sheet temperature reaches a temperature at which heat ray shielding is exhibited. When the addition amount exceeds 5 parts by mass, absorption of near-infrared rays in the near-infrared variable scattering layer is increased, and heat ray permeability at low temperatures and heat ray shielding properties at high temperatures may be insufficient.

  In addition to these near-infrared transmissive colorants, an inorganic pigment for toning may be added to the near-infrared variable scattering layer in order to obtain a desired hue as long as the object of the present invention is not impaired. In the case of using an inorganic pigment, those having little absorption in the near infrared region with a wavelength of 780 to 1600 nm are preferable. Examples of such inorganic pigments include titanium oxide, zinc oxide, tin oxide, zirconium oxide, indium oxide, and antimony trioxide. , Chromium oxide, iron oxide, tin-doped indium oxide, indium-doped tin oxide, antimony-doped tin oxide and other white or chromatic metal oxide particles, and a rutile, hematite, or spinel structure, titanium, Illustrative examples include chromatic metal composite oxide particles containing two or more of zinc, antimony, iron, nickel, cobalt, chromium, magnesium, copper, manganese, aluminum, niobium, and silicon. The surface of these inorganic pigments may be coated with an inorganic or organic substance in order to increase the dispersibility in the transparent matrix resin or suppress the photocatalytic activity. Although these inorganic pigments have little absorption with respect to near infrared rays of 780 nm to 1600 nm, they are scattered over a part or all of the wavelength of the region, so the addition amount when added to the near infrared variable scattering layer is soft polychlorinated The amount is preferably 8 parts by mass or less and more preferably 5 parts by mass or less with respect to 100 parts by mass of the vinyl resin composition. If the amount added exceeds 8 parts by weight, heat ray permeability at low temperatures may not be obtained. The average particle size of the inorganic pigment is preferably 0.15 to 0.40 μm, and more preferably 0.20 to 0.35 μm. If the average particle diameter of the inorganic pigment is within this range, the effect of toning is obtained in the visible light region, the scattering of the near infrared region by the pigment particles is suppressed, and the heat ray permeability at low temperatures is not impaired. If the average particle size is less than 0.15 μm, the coloring power is weak and the toning may not be possible, and if it exceeds 0.40 μm, scattering in the near-infrared region increases, and heat ray permeability at low temperatures is impaired. Sometimes.

  The heat-controllable sheet of the present invention is preferably a laminate comprising a fibrous knitted fabric as a base fabric. By including the fibrous knitted fabric, the heat-controllable sheet can be given strength and durability, and can be applied to tent warehouses, large event tents, awning tents, awning monuments, decorative tents, and the like. The materials used for fibrous knitted fabrics include synthetic fibers such as polypropylene fiber, polyethylene fiber, polyester fiber, nylon fiber, and vinylon fiber, natural fibers such as cotton and hemp, semi-synthetic fibers such as acetate, glass fibers, and silica fibers. Inorganic fibers such as alumina fibers and carbon fibers, which may be composed of single or a mixture of two or more kinds, and the shapes thereof are multifilament yarn, short fiber spun yarn, monofilament yarn. Any of a split yarn yarn, a tape yarn yarn and the like may be used. In the case of a woven fabric, the fibrous knitted fabric used in the present invention may have any structure such as plain weave, twill weave, satin weave, imitation weave, etc., but the plain weave fabric has a balance of longitudinal physical properties of the obtained daylighting membrane material. Since it is excellent, it is preferably used. As the knitted fabric, Russell knitted weft insertion tricot is preferably used. These knitted fabrics are each a coarse knitted fabric composed of yarns including warps and wefts arranged in parallel with a gap between yarns (the porosity is 80% at maximum, preferably 5 to 50%) And non-coarse knitted fabrics (knitted fabrics having a porosity of less than 5% and substantially no gap formed between yarns).

  The heat-controllable sheet of the present invention prevents at least one layer of the near-infrared variable scattering layer on the near-infrared variable scattering layer in order to prevent deterioration of heat ray permeability or heat ray shielding property due to the adhesion of dirt over time. It is preferable to provide a dirty layer. As long as the antifouling layer does not impair the object of the present invention and does not have extreme concealing properties, there is no particular limitation on the formation method and material, for example, an acrylic resin or fluorine-based solubilized in a solvent. A coating film formed by applying a resin solution comprising at least one resin, a coating film containing silica fine particles or colloidal silica, a coating film containing an organosilicate and / or a condensate thereof, and a hydrophilic coating film A film in which a layer is formed, a photocatalyst layer is formed by applying a coating agent containing a photocatalytic inorganic material (for example, photocatalytic titanium oxide) and a binder, and a film in which at least the outermost surface is formed of a fluororesin. It can be appropriately selected from adhesives or those laminated by hot melt processing.

  An ultraviolet absorber may be added to the antifouling layer. By including the ultraviolet absorber in the antifouling layer, it is possible to suppress the weather resistance deterioration of the transparent matrix resin and the fading of the near-infrared transparent colorant. There are no particular limitations on the UV absorber used for the antifouling layer, and organic UV absorbers such as benzotriazole, benzophenone, benzoate, triazine, salicylate, and cyanoacrylate, zinc oxide, titanium oxide, It can be appropriately selected from ultrafine metal oxide ultraviolet absorbers made of cerium oxide or the like. In the case of using an ultrafine metal oxide ultraviolet absorber, the surface may be coated with an inorganic or organic material in order to suppress photocatalytic activity and to suppress agglomeration. Examples of the coating material include silicon dioxide. Aluminum oxide, hydroxyapatite and the like are preferably used. Moreover, it is preferable that the average particle diameter of an ultrafine metal oxide type ultraviolet absorber is 0.01-0.10 micrometer. When the average particle diameter is in this range, there is almost no light scattering in the visible light region and near infrared region, and a highly transparent antifouling layer can be obtained, and the hue of the heat controllable sheet, heat ray permeability, and , The influence on heat ray shielding is reduced.

  Between the antifouling layer and the near-infrared variable scattering layer, if necessary, an adhesion layer for imparting adhesiveness between the antifouling layer and the near-infrared variable scattering layer, or preventing the resin from being decomposed by the photocatalyst. A protective layer for preventing the additive contained in the near-infrared variable scattering layer from migrating to the antifouling layer may be formed. Further, a back surface adhesive layer for imparting high-frequency heat fusion property and hot air fusion property to the antifouling layer on the surface opposite to the surface on which the antifouling layer is formed of the heat controllable sheet of the present invention. It may be formed. Alternatively, while the heat-controllable sheet is wound into a roll and stored, the additive contained in the near-infrared variable scattering layer or the thermoplastic resin layer on the back side is transferred onto the wound antifouling layer And in order to prevent that antifouling property falls, the additive transfer prevention layer may be formed in the back surface side (surface opposite to an antifouling layer).

  The heat-controllable sheet of the present invention is configured as described above so that it can transmit near infrared rays at a low temperature of 0 to 10 ° C. and exhibit heat ray permeability, and near infrared rays at a high temperature of 60 to 70 ° C. It is possible to show heat ray shielding properties by scattering. At this time, when the sheet is at a low temperature of 0 to 10 ° C., the transmittance of near infrared rays having a wavelength of 780 to 1600 nm (based on JISR3106) is preferably 30% or more, and more preferably 50% or more. If the transmittance of near infrared rays at a low temperature is less than 30%, the heat ray transmittance at a low temperature is insufficient, and when a film structure is constituted by this sheet, it may be difficult to take in heat inside. On the other hand, when the sheet is at a high temperature of 60 to 70 ° C., the transmittance of near infrared rays having a wavelength of 780 to 1600 nm (based on JIS R3106) is preferably 15% or less. If the transmittance of near infrared rays at a high temperature exceeds 15%, when the inside of the membrane structure is configured, the internal temperature becomes extremely high, and it becomes difficult for a person to work for a long time, or cooling is used. In some cases, the energy cost and the environmental burden associated therewith may increase.

The present invention will be specifically described with reference to the following examples and comparative examples, but the present invention is not limited thereto.

In the following Examples and Comparative Examples, the refractive index difference, heat ray permeability, and heat ray shielding properties were evaluated by the following test methods.
<Refractive index difference between transparent matrix resin and transparent particles>
A 200 μm-thick film was formed by a calender method from the soft vinyl chloride resin composition used to constitute the transparent matrix resin in the examples and comparative examples, and the refractive index was 10 ° C. and 60 ° C. according to the JISK7142A method. (Wavelength 589 nm) was measured. On the other hand, the refractive index (wavelength 589 nm) of 10 ° C. and 60 ° C. of the transparent particles used in Examples and Comparative Examples was determined based on the JISK7142B method (Becke line method). However, Cargill standard solution (manufactured by Moritex Co., Ltd.) was used as the immersion liquid. From these results, the refractive index difference at 10 ° C. and the refractive index difference at 60 ° C. were determined.
<Transmittance in the near infrared region>
About the sheet | seat obtained by the Example and the comparative example, based on JISR3106, the spectral transmittance of the near-infrared area | region of wavelength 780-1600nm is made into the sheet | seat with the front surface side facing the incident side of a spectrophotometer. Measurements were made at 10 ° C. and 60 ° C., respectively.
<Heat ray permeability and heat ray shielding>
For the sheet (1) created in the example and the comparative example, a small tent (see FIG. 3) covering the roof and the side wall with the front surface as the outside is created, and there is no high building in the vicinity. On the roof of the building (concrete floor), one side of the inclined surface of the tent roof is facing south, and there is no air circulation to the outside, and the winter (January) and summer (August) tents The internal temperature change was continuously measured and recorded. From the record of the measured data obtained, we extracted the temperature in the tent in the morning (8 o'clock) and afternoon (14 o'clock) on the second day of the second day of sunny weather, and adopted the heat ray permeability in winter (incorporating solar heat) The effect of warming the interior) and the heat ray shielding in summer were evaluated. Further, the sheet temperature at the time when the temperature in the tent was measured was measured with a contact-type surface thermometer using a thermocouple sensor. The seat temperature was measured at the center of the inclined surface of the tent roof facing south. Furthermore, at the time of measuring the sheet temperature in the afternoon (14:00), the slope was observed from a position 3 m away from the south side of the tent, and the appearance of the sheet and the degree of glare were observed and evaluated as follows.
appearance:
1. Under the direct sunlight, in the winter and summer, the sheet appearance by scattering light of transparent particles
2. The appearance of the sheet due to light scattering of transparent particles in direct sunlight and in winter or summer
The effect on the glare is noticeable:
1. I couldn't feel the glare and could see it directly. 2. It was very dazzling and I couldn't see it directly. On the roof of the same building as the tent, It was installed and the outside temperature at the time of the above measurement was continuously measured, and the difference from the ambient temperature was compared.
Tent size: (Figure 3)
50cm height from floor to eaves
Bottom Vertical x Horizontal 50cm x 50cm
Roof angle 20 °
59cm from floor to main building
Temperature measurement position in the tent A sensor is placed 30 cm in height from the floor in the center of the tent (not shown)

[Example 1]
A transparent matrix resin composed of a soft vinyl chloride resin composition of the following formulation 1, the following transparent particles 1, and the following near-infrared transparent colorant 1 are mixed so as to have a mass ratio of 100: 43: 1, and a Banbury mixer The resin mixture 1 was obtained by hot melt kneading. The resin mixture 1 was passed through four calendar rolls set at 180 ° C. to form a bright red near-infrared variable scattering layer film 1-1 having a thickness of 0.25 mm. On the other hand, a hot melt kneaded product of the soft vinyl chloride resin of Formulation 1 was passed through four calendar 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 to obtain a tarpaulin-like sheet. Furthermore, on the surface of the film 1-1 of this sheet, a resin composition of the following formulation 2 was applied using a gravure coater so as to be 30 g / m ^2, and dried at 120 ° C. for 1 minute to 6 g / m ^2. An antifouling layer was formed to obtain a sheet of Example 1. About the obtained sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.
<Formulation 1> Soft vinyl chloride resin composition Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass Di-2-ethylhexyl phthalate (plasticizer) 60 parts by mass Tricresyl phosphate (plasticizer) 15 parts by mass Antimony trioxide ( Flame retardant) 5 parts by weight Zinc stearate (stabilizer) 2 parts by weight Barium stearate (stabilizer) 2 parts by weight Ultraviolet absorber: 0.5 parts by weight of benzotriazole series <Transparent particles 1>
Copolymerized crosslinked fine particles of methyl methacrylate-styrene 79 parts by mass * refractive index (10 ° C.) 1.52, average particle diameter 5 μm
* 43 parts by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition 45 by volume with respect to the soft vinyl chloride resin composition 100
<Near-infrared transparent colorant 1>
C. I. Pigment Red 209 (quinacridone organic pigment) 1.8 parts by mass * 1 part by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition <Composition 2> Resin composition for antifouling layer Trademark: Acryprene pellets HBS001 (Mitsubishi Rayon) 20 mass parts UV absorber 0.2 mass parts * Zinc oxide ultrafine particles with an average particle diameter of 0.02 μm coated with aluminum oxide Toluene-MEK (50/50 weight ratio) (solvent) 80 mass parts < Base fabric 1>
Coarse plain woven fabric using polyester 833 dtex multifilament Density Warp (warp) 18 / inch Weft (weft) 19 / inch

[Example 2]
The amount of the transparent particles 1 is changed to 174 parts by mass (94 parts by mass / 100 parts by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition, and 100 with respect to the soft vinyl chloride resin composition 100). The resin matrix 2 was obtained by heat melting and kneading with a Banbury mixer at a mass ratio of the transparent matrix resin in the layer, the transparent particles 1 and the near-infrared transmitting colorant 1 of 100: 94: 1. The resin mixture 2 was passed through four calendar rolls set at 180 ° C. to form a bright red near-infrared variable scattering layer film 2-1 having a thickness of 0.25 mm. On the other hand, a hot melt kneaded product of the soft vinyl chloride resin of Formulation 1 was passed through four calender rolls set at 180 ° C. to form a film 2-2 having a thickness of 0.25 mm. Next, the base fabric 1 was inserted between the obtained film 2-1 and film 2-2 and laminated by thermocompression to obtain a tarpaulin-like sheet. Further, an antifouling layer was formed on the surface of the film 2-1 of this sheet in the same manner as in Example 1 to obtain a sheet of Example 2. About the obtained sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.

[Example 3]
A tarpaulin-like sheet of Example 3 was obtained in the same manner as Example 1 except that the following transparent particles 2 having an average particle diameter of 15 μm were used instead of the transparent particles 1 having an average particle diameter of 5 μm. Also in Example 3, the near-infrared variable scattering layer had the same appearance as Example 1. About this sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.
<Transparent particles 2>
Methyl methacrylate-styrene copolymer crosslinked fine particles 79 parts by mass * refractive index (10 ° C.) 1.52, average particle diameter 15 μm
* 43 parts by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition 45 by volume with respect to the soft vinyl chloride resin composition 100

[Example 4]
Instead of Formulation 1, the following transparent particle 3 having a refractive index of 1.50 at 10 ° C. is used instead of the transparent vinyl 1 having a refractive index of 1.52 at 10 ° C. Each was used, and the amount of the near-infrared transparent colorant was adjusted as follows, and the mass ratio of the transparent matrix resin, the transparent particles, and the near-infrared transparent colorant in the near-infrared variable scattering layer was 100: 45: A sheet of Example 4 was obtained in the same manner as Example 1 except that the number was 1. About this sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.
<Formulation 3> Soft vinyl chloride resin composition Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by mass 1,2-cyclohexanedicarboxylic acid diisononyl ester (plasticizer)
100 parts by mass Antimony trioxide (flame retardant) 10 parts by mass Zinc stearate (stabilizer) 2 parts by mass Barium stearate (stabilizer) 2 parts by mass UV absorber: 0.5 parts by mass of benzotriazole series <Transparent particles 3>
Cross-linked polymethyl methacrylate fine particles 96 parts by mass * refractive index (10 ° C.) 1.50, average particle diameter 5 μm
* 45 parts by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition 45 by volume with respect to the soft vinyl chloride resin composition 100
<Near-infrared transparent colorant 1>
C. I. Pigment Red 209 (quinacridone organic pigment) 2.1 parts by mass * 1 part by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition

[Example 5]
A sheet of Example 5 was obtained in the same manner as Example 1 except that the following near-infrared transparent colorant 2 was used instead of the near-infrared transparent colorant 1. In Example 5, the near-infrared variable scattering layer had a bright yellow appearance. About the obtained sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.
<Near-infrared transparent colorant 2>
C. I. Pigment Yellow 155 (condensed disazo organic pigment) 1.8 parts by mass * 1 part by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition

[Example 6]
A sheet of Example 6 was obtained in the same manner as in Example 1 except that the following near-infrared transparent colorant 3 was used instead of the near-infrared transparent colorant 1. In Example 6, the near-infrared variable scattering layer had a bright blue appearance. About the obtained sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.
<Near-infrared transparent colorant 3>
C. I. Pigment Blue 15: 3 (phthalocyanine organic pigment) 1.8 parts by mass * 1 part by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition

[Example 7]
In addition to the near-infrared transmissive colorant, 1.1 parts by mass (soft vinyl chloride resin composition) of titanium oxide particles (average particle size 0.21 μm) coated with silicon dioxide as an inorganic pigment with little absorption in the near-infrared region. A sheet of Example 7 was obtained in the same manner as in Example 6 except that 0.6 mass part was further added to 100 parts by mass of the product. In Example 7, the near-infrared variable scattering layer had a light blue appearance. About the obtained sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.

[Example 8]
A sheet of Example 8 was obtained in the same manner as in Example 1 except that the following near-infrared transparent colorant 4 (mixture of three organic pigments) was used instead of the near-infrared transparent colorant 1. In Example 8, the near-infrared variable scattering layer had a black appearance. About the obtained sheet | seat, the result which used for the various tests by making the surface in which the antifouling layer was formed into the front surface is shown in Table 1.
<Near-infrared transparent colorant 4>
C. I. Pigment Red 209 (quinacridone organic pigment) 0.8 parts by mass C.I. I. Pigment Yellow 155 (condensed disazo organic pigment) 0.5 part by mass C.I. I. Pigment Blue 15: 3 (phthalocyanine organic pigment) 0.5 part by mass * 1 part by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition in total

  In all the sheets of Examples 1 to 8, the difference between the refractive index of the transparent matrix resin and the refractive index of the transparent particles is 0.01 or less at a flexible sheet temperature of 0 to 10 ° C., and the flexible sheet temperature is It was a sheet having a heat ray permeability at a sheet temperature of 0 to 10 ° C. in the winter and a heat ray shielding property at a sheet temperature of 60 to 70 ° C. in the summer, satisfying 0.03 to 0.06 at 60 to 70 ° C. . Example 1 was a bright red sheet, and the presence of transparent particles contained in the near-infrared variable scattering layer could not be visually confirmed when the sheet temperature was low in winter. When the sheet temperature is 60 to 70 ° C., the light scattering by the transparent particles can be recognized slightly, but there is almost no influence on the appearance, and even in the summer, even if the sheet temperature becomes 60 ° C. or higher under direct sunlight. I did not feel the scattered light. In Example 2, the amount of transparent particles was larger than in Example 1, so that the heat ray shielding property in summer was superior to that in Example 1. Light scattering by the transparent particles in summer was slightly stronger than that in Example 1, but was not so bright. In Example 3, transparent particles 2 having a particle size larger than that of Example 1 were used. However, since the average particle size was 20 μm or less (15 μm), scattering did not cause wavelength dependence, and heat ray permeability at a low temperature. The results were similar to those of Example 1 with respect to heat ray shielding properties at high temperatures and appearance at high temperatures at low temperatures. In Example 4, the transparent particles 1 having a refractive index of 1.52 used in Example 1 were replaced with transparent particles 3 having a refractive index of 1.50, but the composition of the soft vinyl chloride resin composition was changed to 10 ° C. By adjusting the refractive index, the same result as in Example 1 could be obtained. Example 5 and Example 6 are different in hue from Example 1, but both are vivid colors, and the heat ray permeability at low temperature and the heat ray shielding property at high temperature are slightly different depending on the hue. It was equivalent to Example 1. This slight difference seems to be a difference in absorption characteristics in the near infrared region of the pigment used. Moreover, Example 5 and Example 6 had no problem in appearance, and even in the summer, even when the sheet temperature reached 60 ° C. or higher under direct sunlight, the scattered light was not felt dazzling. Example 7 is a sheet obtained by adding titanium oxide having a smaller particle diameter as an inorganic pigment to the near-infrared variable scattering layer of Example 6 in order to obtain a pastel hue, but at a low temperature of 0 to 10 ° C. The heat ray permeability and the heat ray shielding property at a high temperature of 60 to 70 ° C. are both substantially the same as in Example 6, and even in the summer, even if the sheet temperature becomes 60 ° C. or higher under direct sunlight, the scattered light I did not feel dazzling. Although the near-infrared variable scattering layer of Example 8 had a black appearance, the near-infrared transmittance at 10 ° C. was not significantly different from other examples, and the heat ray transmittance in winter was excellent. The near-infrared transmittance at 60 ° C. was also the same as the other examples, and the heat ray shielding property in summer was excellent. Further, in the summer, when the sheet temperature was 60 ° C. or higher under direct sunlight, the scattering of light by the transparent particles could not be recognized at all and was not felt dazzling.

[Comparative Example 1]
A sheet of Comparative Example 1 was obtained in the same manner as in Example 1 except that instead of the transparent particles 1, the following transparent particles 4 having an average particle diameter of 30 μm were used. The obtained sheet was subjected to various tests using the surface on which the antifouling layer was formed as the front surface.
<Transparent particles 4>
Methyl methacrylate-styrene copolymer crosslinked fine particles 79 parts by mass * refractive index 1.52 (10 ° C.), average particle size 30 μm
* 43 parts by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition 45 by volume with respect to the soft vinyl chloride resin composition 100

  The sheet of Comparative Example 1 showed a bright red color as in Example 1 at a low temperature of 0 to 10 ° C., and had good heat ray permeability. However, the average particle diameter of the transparent particles is as large as 30 μm, the wavelength dependence of light scattering occurs at a sheet temperature of 60 to 70 ° C., and the scattering of red having a longer wavelength than blue having a shorter wavelength is smaller in the visible light region. As a result, an iris pattern occurred and the appearance was damaged. Moreover, in the near-infrared transmittance, although it was 30% or more at 10 ° C. and 15% or less at 60 ° C., the near-infrared transmittance at 60 ° C. was slightly higher than that of the sheet of Example 1. This result also appeared in the evaluation of heat ray shielding properties in summer, which was inferior to each example. This is presumably because near-infrared light having a long wavelength is reduced due to the wavelength dependence of light scattering, and the near-infrared light is transmitted by that amount.

[Comparative Example 2]
A sheet of Comparative Example 1 was obtained in the same manner as Example 1 except that the transparent particles 1 were not added. Table 2 shows the results of various tests using this sheet with the surface on which the antifouling layer was formed as the front surface.

  The sheet of Comparative Example 2 was a bright red sheet, and the near-infrared transmittance was high both at 10 ° C and 60 ° C. Therefore, although it showed good heat ray permeability at a low temperature of 0 to 10 ° C. as in Example 1, it had no heat ray shielding property at a high temperature of 60 to 70 ° C.

[Comparative Example 3]
A sheet of Comparative Example 3 was obtained in the same manner as in Example 1 except that the near-infrared transmitting colorant was not added. Table 2 shows the results of various tests using this sheet with the surface on which the antifouling layer was formed as the front surface.

  The sheet of Comparative Example 3 was a colorless and transparent sheet at a low temperature of 0 to 10 ° C., had a high near-infrared transmittance at 10 ° C., and had good heat ray permeability. At 60 ° C., the refractive index difference between the transparent matrix resin and the transparent particles becomes 0.049, and the near infrared transmittance decreases due to scattering. However, since it does not contain a colorant, the sheet temperature is 60 ° C. even in direct sunlight in summer. In the evaluation using a small tent, the heat ray shielding property in summer was significantly inferior to each example. Further, in the summer, the sheet became cloudy, and the visible light was scattered under direct sunlight in the summer.

[Comparative Example 4]
15 parts by mass of titanium oxide particles (refractive index: 2.73) having an average particle diameter of 1 μm coated with silica as an inorganic pigment without adding transparent particles and a near-infrared transmitting colorant (soft vinyl chloride resin composition 100 mass) A sheet of Comparative Example 4 was obtained in the same manner as in Example 1 except that 8.1 parts by mass with respect to parts and 2.3) was added to the soft vinyl chloride resin composition 100 at a volume ratio. The obtained sheet was subjected to various tests using the surface on which the antifouling layer was formed as the front surface.

  Although the sheet of Comparative Example 4 does not contain transparent particles, by including coarse titanium oxide that scatters near infrared rays, the near infrared transmittance is low at 10 ° C. and 60 ° C., and in the summer, heat shielding properties were exhibited. There was no heat ray permeability in winter. Moreover, it had a white appearance and was very dazzled by scattering visible light under direct sunlight not only in summer but also in winter.

[Comparative Example 5]
The soft vinyl chloride resin composition of Formula 3, transparent particles 4, and near-infrared transmission, as in Example 4, except that the following transparent particles 4 (non-crosslinked polymethyl methacrylate) were used instead of the transparent particles 3. The active colorant 1 was mixed at a mass ratio of 100: 45: 1 and heat melt kneaded with a Banbury mixer to obtain a resin mixture ratio of -5. An attempt was made to pass four calender rolls set at 180 ° C. with a resin mixture ratio of −5, but the resin mixture was stuck to the roll, and a film could not be formed. Therefore, for Comparative Example 5, a sheet into which the base fabric was inserted could not be obtained. However, a film having a resin mixture ratio of -5 and a thickness of 0.25 mm was formed by a hot press machine, and only the near infrared transmittance at film temperatures of 10 ° C. and 60 ° C. was measured. The results are shown in Table 2.
<Transparent particles 4>
Non-crosslinked polymethyl methacrylate fine particles 96 parts by mass * refractive index 1.49 (10 ° C.), average particle size 8 μm

  In Comparative Example 5, since non-crosslinked polymethyl methacrylate fine particles were used, the particles melted when mixed with a soft vinyl chloride resin composition and a near-infrared transmitting colorant, and hot melt kneaded with a Banbury mixer. The resin blended with each other and the resin mixture was insufficient in lubricity, so that a film could not be formed with a calendar, and a tarpaulin-like sheet laminated with a base fabric could not be formed as in each Example. Therefore, although evaluation using a small tent was not performed, the film formed by pressing is a film having high near infrared transmittance at both 10 ° C. and 60 ° C., and the near infrared due to the difference in refractive index between the transparent matrix resin and the transparent particles. Since no change in the transmittance was observed, it is considered that Comparative Example 5 does not have summer heat ray shielding properties.

[Comparative Example 6]
Instead of the near-infrared transparent colorant 4 (a mixture of three organic pigments, a total of 1.8 parts by mass), 3 parts by mass of carbon black (2 parts by mass with respect to 100 parts by mass of the soft vinyl chloride resin composition) A sheet of Comparative Example 6 was obtained in the same manner as Example 8 except for the addition. The obtained sheet was subjected to various tests using the surface on which the antifouling layer was formed as the front surface.

  The sheet of Comparative Example 6 was a sheet having a black appearance as in Example 8, and no glare due to the scattering of visible light was felt under direct sunlight in both winter and summer. The near-infrared transmittance showed a value lower than that of Example 8 regardless of the temperature, and the heat ray transmittance in winter was lower than that of Example 8. On the other hand, despite the low near-infrared transmittance, the heat ray shielding property in summer was inferior to that in Example 8. This is because the sheet of Example 8 shields near infrared rays by scattering at high temperatures, whereas the sheet of Comparative Example 5 shields near infrared rays by absorption of carbon black, so the temperature of the sheet rises. The heat is released as radiant heat from the back side of the sheet into the tent, which is thought to be due to the increase in temperature in the small tent.

  The heat-controllable sheet of the present invention has a high degree of freedom in hue, can transmit near infrared rays in winter, can incorporate solar heat into the film structure, and can scatter near infrared rays contained in sunlight in summer. Thus, the temperature rise inside the membrane structure constituted by this sheet can be suppressed, and there is no adverse effect on the surrounding landscape due to the scattering of visible light. Therefore, in particular, it is used for tent warehouses, large tents for events, agricultural and horticultural houses, awning tents, awning monuments, decorative tents, blinds, seat shutters, etc., to provide a comfortable environment throughout the year without restrictions on hue. Can reduce the energy required for cooling and heating.

1: Thermally controllable sheet 2: Near-infrared variable scattering layer 3: Base cloth 4: Resin layer other than near-infrared variable scattering layer 5: Antifouling layer 6: Small tent 7: Sheet prepared in Examples and Comparative Examples

Claims (8)

  A flexible sheet including a near-infrared variable scattering layer, wherein the near-infrared variable scattering layer includes a transparent matrix resin made of a soft polyvinyl chloride resin composition, and an average particle diameter dispersed in the transparent matrix resin It is composed of 1 to 20 μm transparent particles and a near-infrared transparent colorant, and the transparent particles are at least one selected from crosslinked acrylic particles, crosslinked polystyrene particles, crosslinked acrylic-polystyrene copolymer particles, and glass particles. The difference between the refractive index of the transparent matrix resin (based on the JISK7142A method) and the refractive index of the transparent particles (based on the JISK7142B method) is 0.01 or less at a flexible sheet temperature of 0 to 10 ° C. A heat-controllable sheet characterized by having a flexible sheet temperature of 0.03 or more and 0.06 or less at 60 to 70 ° C. 2. The thermal control according to claim 1, wherein the flexible sheet temperature exhibits heat ray permeability at 0 to 10 ° C. and the flexible sheet temperature exhibits heat ray shielding property at 60 to 70 ° C. 3. Sex sheet.   3. The thermally controllable sheet according to claim 1, wherein in the near-infrared variable scattering layer, the content of the transparent particles is 30 to 150 with respect to the matrix resin 100 in a volume ratio.   The near-infrared transparent colorant is one or two selected from perylene, perinone, phthalocyanine, carbonium, anthraquinone, quinophthalone, azo, azomethine, quinacridone organic pigments and organic dyes. It is the above, In the said near-infrared variable scattering layer, 0.05-5 mass parts of said near-infrared transparent colorants are included with respect to 100 mass parts of said transparent matrix resin, The any one of Claims 1-3. Thermal controllable sheet.   The heat-controllable sheet according to any one of claims 1 to 4, wherein the soft polyvinyl chloride resin composition contains 40 to 150 parts by mass of a plasticizer with respect to 100 parts by mass of the polyvinyl chloride resin.   The heat-controllable sheet according to any one of claims 1 to 5, wherein the flexible sheet is a laminate including a fibrous knitted fabric as a base fabric.   The heat-controllable sheet according to any one of claims 1 to 6, wherein the flexible sheet has at least one antifouling layer as an outermost layer.   The transmittance of near infrared rays having a wavelength of 780 to 1600 nm (based on JISR3106) is 30% or more at a sheet temperature of 0 to 10 ° C, and 15% or less at 60 to 70 ° C. The heat controllable sheet described in 1.