Heat-insulating member and heat-insulating window

Abstract

A heat-insulating window according to the present invention is provided with: a pair of panels; a space sandwiched between the panels; a heat-insulating material that can fill the space; and a mechanism that can fill the space with the heat-insulating material and remove the heat-insulating material. The heat-insulating material is characterized by containing aerogel having a three-dimensional network structure, the skeleton of which is formed by clusters that are aggregates of primary particles, and containing fine particles having the three-dimensional network structure, the skeleton of which is formed by the primary particles. Such heat-insulating material has extremely high flowability and can be moved by liquid, thereby allowing filling and removal of the heat-insulating material into and from the space between the pair of panels. In addition, a heat-insulating member according to the present invention is provided with a cavity, the shape of which can be changed, and a heat-insulating material accommodated in the cavity. The heat-insulating material is a powder, has flowability, has volume retention performance that retains the volume before and after the change in the cavity shape, and moves inside the cavity as the cavity shape changes.

Description

Heat insulating materials and heat insulating windows

[0001] The present invention relates to an insulating member and an insulating window, and is particularly suitable for use in an insulating member that allows the insulating part to be changed, and further suitable for use in an insulating window that can be switched between a transparent state and a light-blocking / heat-blocking state.

[0002] As energy-efficient homes become more popular as a measure against global warming, window insulation is extremely important. This is because it is necessary to prevent heat from entering from the outside in summer and heat from escaping to the outside in winter, and it is also necessary to consider the balance with lighting.

[0003] Patent Document 1 discloses a window unit that can adjust the amount of light and heat insulation by filling or removing foamed resin granules into a hollow space formed between transparent plates, such as a double-pane window. The foamed resin granules are transported from a storage tank by airflow to fill the hollow space, thereby improving heat insulation, and the foamed resin granules are removed from the hollow space by airflow and collected in a storage tank, thereby improving light transmission. The document also points out the problem that the foamed resin granules rub against each other as they are transported by the airflow, becoming electrically charged and adhering to the transparent plates that make up the double-pane window. This problem is solved by applying an antistatic coating to the inner wall of the double-pane window.

[0004] Patent Document 2 discloses a window that makes it possible to adjust the area of ​​the portion that can transmit light. A gap is provided between a pair of glass panels, and an elevator is placed in this gap. Lightweight particles filled on the upper side of the elevator are lowered to the bottom end to create a light-blocking state, and by raising the elevator, the transparent area is increased, allowing light to enter.

[0005] Patent Document 3 discloses a double-pane window that allows hydrophobic aerogel particles to be introduced into and removed from the interior space. The hydrophobic aerogel particles are dropped from a storage section and then collected in the storage section by a blow-up mechanism. An embodiment is also presented in which hydrophobic aerogel particles with a silica skeleton are used as the heat insulating material, a transparent conductive film is formed on the inner surface of the double-pane window, and the inner wall of the double-pane window is charged to allow the hydrophobic aerogel to adhere to it.

[0006] Patent Document 4 discloses a light-shielding member in which aerogel particles are filled into a space sandwiched between two transparent panels. Although there is no mention of a mechanism for switching between a transparent state and a light-shielding / heat-shielding state, the document discloses the results of a detailed analysis of the relationship between the particle size of the aerogel particles to be filled and the visible light transmittance.

[0007] Incidentally, thermal insulation and heat shielding are technical terms that should be clearly distinguished in a technical sense, but in this specification they are used synonymously.

[0008] JP-A-5-86780 JP-A-5-202681 JP-A-11-30085 JP-A-2018-178372

[0009] As shown in Patent Documents 1 to 4, various double-paned windows have been proposed that block heat by filling the gaps between the windows with insulating material such as aerogel particles. The inventions disclosed in Patent Documents 1 to 3 include a mechanism that switches between a state in which insulating material such as aerogel particles is filled and a state in which it is removed, thereby controlling the balance between insulation and light transmission, but the control mechanism is complex. The double-paned windows disclosed in Patent Documents 1 and 3 require an air supply fan and valves to move the particulate insulating material with airflow, as well as a heater to prevent condensation, a transparent conductive film to charge the inside of the window, and a control circuit. The double-paned window disclosed in Patent Document 2 is equipped with an elevator to mechanically move the particulate insulating material. This is because insulating materials such as aerogel require a certain size, and a certain level of physical force is required to move them.

[0010] The inventors have noticed that mechanisms that can switch between insulating and non-insulating and adjust the insulating performance of general insulating materials (including insulating building materials for walls, floors, roofs, etc.) that make up cold and hot insulation containers have not yet been studied or put into practical use. This is thought to be because adjusting the insulation in insulating materials requires a complex mechanism similar to that studied in the prior art for windows above.

[0011] An object of the present invention is to provide a heat insulating member and a heat insulating window having a simple mechanism for adjusting the heat insulating state (areas to be insulated and heat insulating performance).

[0012] The means for solving these problems will be described below, but other problems and novel features will become apparent from the description of this specification and the accompanying drawings.

[0013] According to one embodiment of the present invention, the following is true.

[0014] In other words, the insulating window of the present invention is an insulating window that comprises a pair of panels, a space sandwiched between them, an insulating material that can fill the space, and a mechanism that can fill and remove the insulating material from the space, and has the following features.

[0015] The heat insulating material is made from an aerogel having a three-dimensional network structure in which the skeleton is formed by clusters, which are aggregates of primary particles, and contains fine particles having a three-dimensional network structure in which the skeleton is formed by the primary particles.

[0016] The mechanism is a mechanism that can change the shape of the space in order to move the insulating material.

[0017] The fine particles constituting the heat insulating material according to the present invention can additionally have the characteristic that 50% or more of their volume are dispersed with a particle diameter having a mode of 0.1 μm to 1.0 μm.

[0018] The insulating member according to the present invention includes a cavity that can change its shape and an insulating material contained in the cavity. The insulating material is a powder that moves within the cavity as its shape changes. Here, the term "cavity" refers to a hollow space within the insulating member that can house the insulating material. For example, the hollow space may be a space formed between a pair of panels, or a bag that can house the insulating material. In this specification, the pair of panels or the bag containing the insulating material are referred to as the insulating member, and the hollow space within the insulating member that can house the insulating material is referred to as the cavity. Meanwhile, the hollow space created using the insulating member for keeping things cool or warm is referred to as a container.

[0019] The effects obtained by the embodiment are briefly described below.

[0020] That is, it is possible to provide a heat insulating member and a heat insulating window having a simple mechanism for adjusting the heat insulating state (the location to be insulated and the heat insulating performance).

[0021] FIG. 1 is a schematic cross-sectional view showing an example of the configuration of an insulating window according to one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of the configuration of an insulating window according to another embodiment of the present invention. FIG. 3 is an explanatory diagram comparing the structures of general aerogel particles and fine particles whose skeletons are formed by primary particles. FIG. 4 is an explanatory diagram showing an example of the frequency distribution of particle diameters for general aerogel granules, a powder and fine powder obtained by pulverizing the aerogel granules, and fine particles whose skeletons are formed by primary particles. FIG. 5 is an explanatory diagram showing a method for measuring the dynamic angle of repose. FIG. 6 is an explanatory diagram showing the results of measuring the dynamic angle of repose. FIG. 7 is an explanatory diagram showing a method for measuring the volume change rate. FIG. 8 shows the results of measuring the volume change rate. FIG. 9 shows the results of measuring the change in the volume change rate over time. FIG. 10 is a schematic cross-sectional view showing an example of the configuration of an insulated container using the insulating member of the present invention. FIG. 11 is a schematic cross-sectional view showing another example of the configuration of an insulated container using the insulating member of the present invention. FIG. 12 is a schematic cross-sectional view showing yet another example of the configuration of an insulated container using the insulating member of the present invention. FIG. 13 is a schematic cross-sectional view showing an example of the configuration of an insulating window according to yet another embodiment of the present invention.

[0022] 1. Solution Principle of the Present Invention The principle by which the present invention has been able to solve the above-mentioned problems will be explained.

[0023] The inventors have invented an insulating material that uses aerogel, which has a three-dimensional network structure with a skeleton formed by clusters that are aggregates of primary particles, as a raw material, and contains fine particles with a three-dimensional network structure with a skeleton formed by these primary particles. Patent application No. 2020-193892 has been filed. This insulating material is called TIISA (trademark registration pending by Thermalytica Inc.). TIISA has thermal conductivity equivalent to that of high-performance aerogel and a bulk density of 0.01 g / cm. 3Its particle size is less than one-tenth that of ordinary aerogel, making it a lightweight, high-performance heat-insulating material. While the skeleton of ordinary aerogel is formed from secondary particles, TIISA's skeleton is formed mainly from the primary particles that make up the secondary particles, resulting in extremely small particles, with more than 50% of the volume dispersed with a mode of particle diameter between 0.1 μm and 1.0 μm.

[0024] 3A and 3B are explanatory diagrams showing the structure of a typical aerogel particle and that of a fine particle having a skeleton formed by primary particles. The three-dimensional network structure of a typical aerogel particle 13 is composed of units of secondary particles 12, which are clusters of primary particles 11 (FIG. 3A). On the other hand, the fine particles of the present invention (e.g., TIISA fine particles) 14 have a three-dimensional network structure formed with the primary particles 11 as the skeleton (FIG. 3B).

[0025] Generally available aerogel is a granular material with a three-dimensional network structure, with a skeleton consisting of secondary particles (12). Therefore, even if the aerogel is finely pulverized using a pulverizer, the skeletal structure remains unchanged. The experimental results are shown below. Figure 4 shows an example of the particle size frequency distribution for aerogel granules, aerogel powder, aerogel fine powder, and TIISA, a fine particle with a skeleton formed by primary particles, from bottom to top. The aerogel granules are the same as those commonly available. The aerogel powder was produced by pulverizing aerogel granules at 5,000 to 7,000 rpm for 2 minutes using a Spinmix Homogenizer SX08 manufactured by Mitsui Electric Seiki Co., Ltd. The aerogel fine powder was produced by pulverizing aerogel granules at 21,000 rpm for 20 seconds using a STEALTH885 manufactured by Blendtec. The horizontal axis of Figure 4 represents particle size, and the vertical axis represents particle size frequency distribution. The right-hand vertical axis shows frequency, and the left-hand vertical axis shows cumulative values. Figure 4 shows the results of measurements using a laser diffraction particle size distribution (PSD) analyzer. In this specification, particle size is explained based on PSD measurements. However, because PSD measurements measure not only the particle size but also particle agglomerations, the true particle size is likely smaller than the measured value. If there are differences in particle size depending on the measurement method, please convert them for better understanding. More specifically, Figure 4 shows the particle size distribution measured using a Shimadzu SALD-2300 laser diffraction particle size distribution analyzer. Particle size distribution is an index that indicates the size (particle diameter) of particles and their proportion (relative particle amount, with the total being 100%) contained in the sample particle group being measured. The order of particle amount is based on volume.

[0026] Commonly available aerogel granules have a single peak in relative particle mass with an average particle size of approximately 400 μm (bottom panel in Figure 4). When these aerogel granules are crushed using the equipment described above, the aerogel powder has an average particle size of approximately 90 μm, and the aerogel fine powder has an average particle size of approximately 50 μm, but each has a single peak in relative particle mass (third and second panels). In contrast, TIISA has two peaks: a first peak at an average particle size of approximately 20 μm and a second peak at an average particle size of approximately 0.3 μm. The first peak at an average particle size of approximately 20 μm accounts for 21.2% of the relative particle mass, and the second peak at an average particle size of approximately 0.3 μm accounts for 78.8%. This is because the first peak at an average particle size of approximately 20 μm is composed of fine particles with a three-dimensional network structure formed by a skeleton of secondary particles 12, while the second peak at an average particle size of approximately 0.3 μm is composed of fine particles with a three-dimensional network structure formed by a skeleton of primary particles.

[0027] Because the skeleton of the three-dimensional network structure of ordinary aerogel is made up of secondary particles, it is difficult to produce fine particles with a particle size of 10 μm or less, no matter how high the milling conditions are. To produce fine particles with a three-dimensional network structure whose skeleton is made up of primary particles, fundamental changes to the manufacturing method are required, such as significant changes to not only the milling conditions but also the aging conditions, as described in Japanese Patent Application No. 2020-193892, unlike the usual aerogel manufacturing process.

[0028] The inventors have newly discovered through experiments described below that TIISA exhibits high fluidity and volume retention comparable to that of a liquid. The dynamic angle of repose and the rate of volume change were used as indicators of fluidity and volume retention, respectively. For example, the angle of repose used in Patent Document 4 is a static angle of repose, which is suitable for measuring powders but is not necessarily appropriate for representing the fluidity of fluids. The inventors also realized that while thermal insulation is subjected to external forces as it flows, i.e., moves, its volume does not change as a result, i.e., its volume retention is also an important characteristic.

[0029] [Dynamic Angle of Repose] Figure 5 is an explanatory diagram (schematic cross-sectional view) showing a method for measuring the dynamic angle of repose. A dynamic angle of repose measuring device 90 is configured so that a sample 91 is placed in a cylindrical glass container 92, placed on two rotating pipe-shaped rollers 93, and rotated, allowing the sample 91 to be observed from the bottom side of the glass container 92. The surface of the sample 91 is horizontal when not rotating, and the surface tilts depending on the rotation speed, so the angle θ from the horizontal is measured as the dynamic angle of repose.

[0030] Figure 6 is an explanatory diagram showing the results of measuring the dynamic angle of repose. The top row shows water, while the rest, similar to Figure 4, are shown, from bottom to top, for aerogel granules, aerogel powder, aerogel fine powder, and TIISA, a fine particle with a skeleton formed by primary particles, at rotation speeds of 16 rpm, 32 rpm, and 48 rpm. Although the surface shape is not flat, as indicated by the dashed line in Figure 6, the angle θ is quantified using a linear approximation. At a rotation speed of 48 rpm, the angle θ is 6° for water, 50° for aerogel granules, aerogel powder, and aerogel fine powder, respectively, while the angle θ for TIISA ranges from 6 to 15°. The dynamic angle of repose for aerogel granules is largest, while that for TIISA is smaller than that for aerogel powder and aerogel fine powder, indicating that it is closer to that for water.

[0031] [Volume Change Rate] The volume change rate is an index that the inventors of the present invention have adopted as one of the indices showing the fluidity of TIISA, and is measured by the following method.

[0032] Figure 7 is an explanatory diagram showing a method for measuring the volume change rate. The sample 91 is placed in a transparent, cylindrical elastic tube 96 and is sandwiched between compression blocks 97 on both sides. The upper side of Figure 7 is a cross-sectional view from the side, and the lower side is a cross-sectional view from above of the sandwiched point x-x. From the initial state, the width of the compression block 97 is narrowed to compress the sample to a compressed state, and then it returns to its original state (called the recovered state). The elastic tube 96 is a pipe-shaped container with a diameter of 12 mm and a wall thickness of 0.25 mm. In the compressed state, the short side in the compressed direction is 6 mm and the long side in the vertical direction is 16 mm, but in the recovered state, it returns to its original diameter of 12 mm. The height h of the sample 91 in the initial state I Therefore, in the compressed state, the height is h HIn the recovery state, the height is h L If the fluid is perfect and there is no change in volume, the height of the recovered state is h L is the initial height h I It will be restored to.

[0033] Figure 8 shows the measurement results of the volume change rate. The horizontal axis represents the depth of compression by the compression block 97, and the horizontal axis represents the change in surface height from the initial state h H -h I The graph shows the change in surface height from the initial state, with the vertical axis being 0.87. The change in surface height from the initial state is roughly proportional to the depth of compression, although not strictly speaking. The maximum change in surface height for water, which is a perfect fluid, was 15 mm, while that for TIISA was 13 mm, for aerogel fine powder 6 mm, for aerogel powder 5 mm, and for aerogel granules 2 mm. When the change in surface height for water is set to 1, the relative values ​​of the changes for TIISA, aerogel fine powder, aerogel powder, and aerogel granules were 0.87, 0.40, 0.33, and 0.13, respectively.

[0034] Figure 9 shows the results of measuring the volume change over time. The horizontal axis represents the logarithmic number of cycles of compression and recovery, and the vertical axis represents the percentage change in volume of Sample 91 from its initial state. Similar to the fact that the volume of water, a perfect fluid, remains constant with repeated compression and recovery (volume change = 0%), the volume change of TIISA also remained constant after 100 cycles of compression and recovery (volume change = 0%). Meanwhile, the volume change of aerogel granules was 21%, 53%, and 63% after 1, 10, and 100 cycles, respectively. The volume change of aerogel powder was 32%, 42%, and 53% after 1, 10, and 100 cycles, respectively. The volume change of aerogel fine powder was 42%, 53%, and 84% after 1, 10, and 100 cycles, respectively. All of these changes resulted in a volume increase from the initial state. This is thought to be the result of the repeated compression and recovery partially destroying the three-dimensional network structure, causing the gaps to become larger.The results of this experiment and discussion show that commonly available aerogels, whether in granular form or crushed, undergo irreversible changes in volume as they are compressed and recovered.

[0035] It was also found that TIISA can be made extremely hydrophobic (TIISA can also be processed to be hydrophilic). The inventors noticed that TIISA's high fluidity is comparable to that of a liquid, and realized that it is possible to move it using a liquid, rather than using air as in Patent Documents 1 to 3. They also discovered that by taking advantage of its high hydrophobicity, the liquid can be water.

[0036] When a liquid, especially water, is used as a medium, it is relatively easy to contain it to prevent diffusion and leakage, and it is also easy to move it. If the medium is a liquid primarily composed of water, it can form a clear interface without mixing with the highly hydrophobic TIISA. Furthermore, the mechanism for containing and moving the liquid (water) as a medium can be a simple elastic cavity, making it extremely simple. By compressing such an elastic cavity, for example by applying pressure, and pushing out the medium, the TIISA can be moved to the desired position, and conversely, by releasing the compressed state, it can be returned to its original position.

[0037] The fine particles that can be used as heat insulating materials are referred to as "TIISA," and there are other places in this specification where "TIISA" is also used to describe the material substance of heat insulating materials, but it goes without saying that the same solution principle applies to materials with equivalent fluidity and volume retention performance.

[0038] By utilizing this principle, it is possible to easily construct a mechanism that moves the heat insulating material to a desired position. In particular, when applied to double-glazed windows, it is possible to easily construct a mechanism that switches between heat insulation and lighting.

[0039] 2. Overview of the Embodiments First, an overview of the representative embodiments disclosed in the present application will be described. Reference numerals in parentheses in the drawings used in the overview of the representative embodiments merely illustrate components included in the concept of the components to which the reference numerals are attached.

[0040] [1] <Insulated window using TIISA as a thermal insulation material> A typical embodiment of the present invention is an insulated window (10) comprising a pair of panels (7), a space (8) sandwiched between the pair of panels, a thermal insulation material (1) that can be filled into the space, and a mechanism (2-6) that can move the thermal insulation material into the space to fill it and move it out of the space to remove it, and has the following features.

[0041] The heat insulating material is made from an aerogel (13) having a three-dimensional network structure whose skeleton is formed by clusters (12) that are aggregates of primary particles (11), and contains fine particles (14) having a three-dimensional network structure whose skeleton is formed by the primary particles (11).

[0042] This makes it possible to provide an insulated window with a simple mechanism for adjusting insulation and lighting. The mechanism for moving the insulating material can be realized in various ways. Since the insulating material has high fluidity and volume retention performance comparable to that of a liquid, the mechanism may be one that moves the insulating material using a liquid as a medium, as described in [3] below, or one that moves the insulating material by applying force to the insulating material itself by adjusting the volume of the space (cavity) that contains the insulating material, just like a liquid.

[0043] It should be noted that "a pair of panels" means "at least one pair of panels," and the insulating window may be a multi-panel window having a plurality of panels (7) and a plurality of spaces (8). In this case, the insulating material may be filled / removed in the same way in the plurality of spaces, or may be filled / removed independently in each space, or some spaces may not be filled / removed.

[0044] [2] <Features of TIISA: Particle diameter> In the insulating window of [1], the fine particles constituting the insulating material are characterized in that 50% or more of their volume are dispersed with a particle diameter of 0.1 μm or more and 1.0 μm or less as the mode.

[0045] This characteristic ensures that the insulating material has high fluidity.

[0046] [3] <Mechanism for moving insulating material using a liquid as a medium> In the insulating window of [1] or [2], the mechanism is a mechanism that can move a liquid in contact with the insulating material in order to move the insulating material.

[0047] This makes it possible to provide an insulated window with a simple mechanism for adjusting the heat insulation and lighting. By employing a mechanism that uses a liquid as a medium to move the insulating material, it is possible to use a mechanism that is widely used to move the liquid while suppressing liquid leakage.

[0048] [4] <The medium that moves the insulating material is water> The insulating window of [3] is characterized in that the liquid is mainly composed of water.

[0049] This allows the mechanism for moving the heat insulating material to be constructed at low cost.

[0050] [5] <Switching between filling with insulation material and air> In the insulated window of any one of [1] to [4], the mechanism comprises an elastic cavity (4) on the lower side of the space that can accommodate the insulation material (and the liquid), and a compression mechanism (3) that can increase or decrease the volume of the elastic cavity.

[0051] The mechanism moves the insulating material from the elastic cavity to the space by reducing the volume of the elastic cavity with the compression mechanism, and moves the insulating material from the space into the elastic cavity by increasing the volume of the elastic cavity with the compression mechanism.

[0052] This allows the mechanism for moving the heat insulating material to be configured simply.

[0053] [6] <Switching between filling with insulation material / liquid (water)> In the insulated window of [3] or [4], the mechanism comprises an upper elastic cavity (5) on the upper side of the space that can accommodate the insulation material, a lower elastic cavity (4) on the lower side of the space that can accommodate the liquid, and a compression mechanism (3) that can increase or decrease the volume of the lower elastic cavity.

[0054] The mechanism reduces the volume of the lower elastic cavity using the compression mechanism, thereby moving the liquid from the elastic cavity to the space and moving the insulating material from the space to the upper elastic cavity, and increases the volume of the lower elastic cavity using the compression mechanism, thereby moving the liquid from the space into the lower elastic cavity and moving the insulating material from the upper elastic cavity to the space.

[0055] This allows the mechanism for moving the heat insulating material to be configured simply.

[0056] [7] <Thermal insulation member constructed using a fluid thermal insulation material> A typical embodiment of the present invention is an insulating member (20) comprising a cavity (21) capable of changing its shape and a thermal insulation material (1) contained in the cavity, wherein the thermal insulation material is a powder that moves within the cavity as the shape changes.

[0057] This makes it possible to provide an insulating member having a simple mechanism for adjusting the thermal insulation. The insulating member is a component constituting an insulating container, etc., and can be a component constituting an insulating container, etc., in addition to an insulating building material such as the insulating window described above. The cavity may have any shape, as long as it has a gap sandwiched between side walls of a pair of panels, etc., and can accommodate an insulating material in the gap. Furthermore, changes in shape include, for example, changes that cause a change in the volume of the cavity, as well as any changes such as changes in shape that change the location where the insulating material is held or changes in shape that change the thickness of the insulating material.

[0058] [8] <Thermal insulation member using TIISA as a thermal insulation material> In the thermal insulation member of [7], the thermal insulation material is made from an aerogel (13) having a three-dimensional network structure whose skeleton is formed by clusters (12) that are aggregates of primary particles (11), and contains fine particles (14) having a three-dimensional network structure whose skeleton is formed by the primary particles.

[0059] This characteristic ensures that the insulating material has high fluidity and volume retention.

[0060] [9] <Thermal insulating component using an insulating material with fluidity and volume retention ability> In the thermal insulating component of [7], the insulating material has fluidity and volume retention ability to maintain the volume before and after the change in the shape of the cavity.

[0061] As long as the insulating material has high fluidity and volume retention, it can be used in the insulating component of the present invention even if it does not have the characteristic described in [7] above. This applies to all embodiments, including the insulating window described in [1] to [5] above.

[0062]

[10] <Decompression of Cavity> In the heat insulating member of [7] or [8], the pressure inside the cavity is reduced below the atmospheric pressure.

[0063] This allows the thermal conductivity of the heat insulating member to be significantly reduced (improving the heat insulating performance). In particular, the improvement in heat insulating performance is more remarkable in [7].

[0064]

[11] <Filling of cavity with gas having thermal conductivity lower than that of air> In the heat insulating member of [7] or [8], the cavity is filled with gas having thermal conductivity lower than that of air (for example, carbon dioxide).

[0065] This reduces the thermal conductivity of the heat insulating material (improving its heat insulating performance). It is easier to maintain the filled state for a longer period than maintaining the reduced pressure state after depressurization as in [9] above. It is also easy to combine it with the following

[11] to

[14] .

[0066]

[12] <Movement of insulating material using a liquid as a medium> In the insulating member of [7], the cavity further contains a liquid (2) that is exclusive to the insulating material. Here, exclusivity is the opposite of affinity and means the property of not mixing with the insulating material, and corresponds to hydrophobicity, which is the property of a substance not mixing with water, for example.

[0067] This allows the mechanism for moving the heat insulating material to be configured simply.

[0068]

[13] <Movement of heat insulating material using water as a medium> In the heat insulating member of [7], the heat insulating material is hydrophobic, and water (2) is further accommodated in the cavity.

[0069] This allows water to be used as a medium for moving the heat insulating material, and the mechanism can be configured simply.

[0070]

[14] <Thermal insulation moving mechanism> In the thermal insulation member of [7], the cavity has one or more pairs of panels (21i, 21w) and a thermal insulation storage section (23), and each of the one or more pairs of panels has a gap (22) inside which the thermal insulation can be stored. The thermal insulation storage section stores the thermal insulation and pushes the thermal insulation into or recovers the thermal insulation from the gap between the panels by changing the volume of a space continuous with the gap.

[0071] This allows the heat insulating material to be moved between the gap between the paired panels and the heat insulating material storage section, thereby adjusting the heat insulating performance of the panel portion.

[0072]

[15] <Insulating material moving mechanism using liquid as a medium> In the insulating member of

[12] , the cavity has one or more pairs of panels (21i, 21w), an insulating material storage section (23), and a liquid storage section (24), and each of the one or more pairs of panels has a gap (22) inside which the insulating material can be stored.

[0073] The insulation material storage section has a space that is continuous with the gap and can store the insulation material in the space, and the liquid storage section stores the liquid and can move the liquid by changing the volume of the space that is continuous with the gap, and can push the insulation material into the gap between the panels or recover it from the gap between the panels.

[0074] This allows the insulating material to be moved between the gap between the paired panels and the insulating material storage section, thereby adjusting the insulating performance of the panel section. The liquid storage section (24) is a volume adjustment mechanism that uses a liquid as a medium. Because a liquid (e.g., water) is used as the medium for moving the insulating material, it has the effect of preventing leakage even if there are moving parts, and it allows for greater freedom in designing the volume adjustment mechanism.

[0075] 3. Details of the embodiment The embodiment will be described in further detail.

[0076] First Embodiment FIG. 1 is a schematic cross-sectional view showing an example of the configuration of an insulating window 10 according to one embodiment of the present invention.

[0077] The insulating window 10 of this embodiment includes a pair of panels 7, a space 8 sandwiched between them, an insulating material 1 that can be filled in the space 8, and mechanisms 2-6 that can move the insulating material 1 into the space 8 and fill it therein, and move it out of the space 8 and remove it. The insulating material 1 is made from aerogel 13 having a three-dimensional network structure whose skeleton is formed by clusters 12, which are aggregates of primary particles 11, and contains microparticles 14 having a three-dimensional network structure whose skeleton is formed by the primary particles 11. The mechanism can move a liquid 2 that is in contact with the insulating material 1 in order to move the insulating material 1. Using the liquid 2 as a medium to move the insulating material 1 has the advantages of being easier to seal than using a gas (air), and since there is almost no change in volume when pressure is applied, the applied pressure can be directly transmitted to the insulating material 1 and moved. This makes it possible to provide an insulating window 10 with a simple mechanism for adjusting insulation and lighting.

[0078] The fine particles 14 constituting the thermal insulating material 1 should preferably have a frequency distribution of particle diameters with a mode (peak) of 1.0 μm or less, and more preferably, 50% or more of the volume should be dispersed with a mode of particle diameters between 0.1 μm and 1.0 μm. This characteristic of the thermal insulating material 1 ensures high fluidity of the thermal insulating material 1.

[0079] The insulating material 1 is preferably a powder of fine particles with the above particle size distribution characteristics, but is not limited to this. Any material with similar fluidity (dynamic angle of repose) and volume retention performance will suffice. For example, referring to the experimental results shown in Figure 6 regarding the dynamic angle of repose, it can be seen that an insulating material with a dynamic angle of repose three to four times that of water can be used. It is also desirable that the volume retention performance be similar to that of a liquid. The mechanism for moving the insulating material is optimally designed using the force applied to the insulating material to move it, the frequency of movement, and the insulating material's lifespan as parameters.

[0080] In this insulating window 10, it is preferable that the liquid 2 be a liquid whose main component is water. This is because by using a highly hydrophobic and highly fluid material for the insulating material 1 as described above, the insulating material 1 does not mix with the liquid 2 whose main component is water, forming a clear interface, and can be moved smoothly by the liquid 2. Furthermore, by using water as the liquid 2, the mechanism for moving the insulating material can be constructed at low cost.

[0081] The mechanism for moving the insulating material 1 can be configured, for example, as shown in Figure 1. In an insulating window 10, this mechanism has a lower elastic cavity 4 and an upper elastic cavity 5 on the upper and lower sides of a space 8 sandwiched between transparent panels 7, such as glass. The mechanism is composed of a frame that supports the panels 7 and houses the lower elastic cavity 4 and the upper elastic cavity 5, respectively. The lower frame 6 houses a compression mechanism 3 that can control the volume of the lower elastic cavity 4. As shown in Figure 1(a), the lower elastic cavity 4 has a volume large enough to contain the insulating material 1 and liquid 2 within the lower frame 6. At this time, the space 8 is filled with air, and the insulating window 10 is transparent and transmits visible light. The upper elastic cavity 5 has a minimum volume. The lower elastic cavity 4 reduces in volume when pressure is applied by the compression mechanism 3 installed around it, pushing the insulating material 1 into the space 8. The space 8 is filled with the insulating material 1, providing heat insulation. At this time, the upper elastic cavity 5 expands to accommodate the air pushed out from the space 8. This makes it possible to easily configure a mechanism for moving the heat insulating material.

[0082] The lower elastic cavity 4 is bonded to the panel 7 at its lower end, and the upper elastic cavity 5 is bonded to the panel 7 at its upper end, sealing the space 8 to prevent the insulation material 1 from leaking and the liquid 2 from volatilizing. The lower and upper elastic cavities 4, 5 can be made of, for example, rubber or latex. The lower elastic cavity 4 is preferably configured to maximize its volume by expanding due to the weight of the liquid 2 contained therein. The upper elastic cavity 5 is preferably configured to naturally expand by accommodating air and to naturally contract as the space 8 is decompressed as the liquid 2 returns to the lower elastic cavity 4. The compression mechanism 3 that compresses the lower elastic cavity 4 can be configured, for example, by a mechanism that transmits pressure applied from outside the frame directly or by amplifying the displacement using gears.

[0083] The mechanism for moving the insulating material 1 can be implemented in various ways different from that of the first embodiment. For example, instead of the lower elastic cavity 4, a cavity for accommodating the insulating material 1 can be provided in the lower part of the space 8 sandwiched between the pair of panels 7, and the insulating material 1 can be moved into the space 8 by injecting the liquid 2 as a medium into the cavity. This is effective in cases where the panels 7 are large, the volume of the insulating material 1 required to fill the space 8 is large, and the power required to move the insulating material 1 into the space 8 is large, in that it can be configured so that the liquid 2 can be injected using energy such as electricity.

[0084] Furthermore, for example, the lower elastic cavity 4 can be configured to extend to the left and right window frames. The window frame can be made smaller by effectively utilizing the volume of the window frame that contains the liquid (water) 2. Furthermore, by appropriately balancing the water levels when the liquid (water) 2 is contained in the left and right window frames, the weight of the liquid (water) 2 contained in the left and right window frames can be used as a force to push up the insulating material 1 from within the lower frame, allowing the insulating material 1 to be moved with a weak force.

[0085] Although the gas filling the space 8 has been described as air, this can be replaced with a gas with lower thermal conductivity, such as carbon dioxide, which can prevent a decrease in the heat-shielding performance in a transparent state.

[0086] [Embodiment 2] Figure 2 is a schematic cross-sectional view showing an example of the configuration of an insulating window 10 according to another embodiment of the present invention. The configuration is basically the same as the insulating window 10 of embodiment 1 shown in Figure 1, except that the lower elastic cavity 4 has a volume large enough to accommodate the liquid 2 within the lower frame 6, and the upper elastic cavity 5 has a volume large enough to accommodate the insulating material 1 within the upper frame 6. When the lower elastic cavity 4 accommodates the liquid 2 and the insulating material 1 fills the space 8, the insulating window 10 enters a heat-blocking state (Figure 2(a)). When the lower elastic cavity 4 is compressed, the liquid 2 is forced into the space 8, and the upper elastic cavity 5 accommodates the insulating material 1, the insulating window 10 enters a transparent state (Figure 2(b)). This explanation naturally assumes that the liquid 2 is transparent. By making the liquid 2 translucent to the same degree as the insulating material 1, the heat-blocking performance can be controlled without changing the transparency and thus without affecting light transmission. The liquid 2 can also be made more opaque than the insulating material 1. This embodiment also allows for a simple configuration of a mechanism for moving the insulating material.

[0087] The cost of the construction can be reduced by using water as the liquid 2. If the panel 7 is made of a hydrophilic material such as glass, the inner wall of the panel 7 will become wet when the liquid (water) 2 is discharged, but the aesthetic appearance will not be impaired because the space 8 is filled with the translucent heat insulating material 1 and the window will remain translucent.

[0088] The detailed implementation and various modifications described in the first embodiment can also be applied to the second embodiment.

[0089] [Embodiment 3] In both embodiments 1 and 2, the mechanisms (4 to 6) are configured using a liquid (water) 2 as a medium to move the insulating material 1, but the mechanism for moving the insulating material 1 can be realized in various other ways.

[0090] Figure 13 is a schematic cross-sectional view showing an example of the configuration of an insulated window 10 according to yet another embodiment of the present invention. It is basically configured similarly to the insulated window 10 of embodiments 1 and 2 shown in Figures 1 and 2, but has a mechanism that applies force to the insulating material 1 itself to move it, rather than using liquid (water) 2 as a medium. That is, the lower elastic cavity 4 has a volume that can accommodate the insulating material 1 within the lower frame 6, and the upper elastic cavity 5 has a volume that can accommodate air pushed out by the insulating material 1 within the upper frame 6. Other configurations are similar to those of embodiments 1 and 2, so repeated explanations will be omitted.

[0091] The lower elastic cavity 4 is compressed, forcing the contained insulating material 1 out and filling the space 8, thereby placing the insulating window 10 in a heat-blocking state (FIG. 13(a)). At this time, gases such as air in the space 8 are further forced out, causing the upper elastic cavity 5 to expand within the frame 6. Meanwhile, when the lower elastic cavity 4 is released from compression and expands, and the insulating material 1 pushed out into the space 8 returns to be contained within the lower elastic cavity 4, the insulating window 10 becomes transparent (FIG. 13(b)). In this way, a mechanism can be constructed in which the insulating material 1 is moved by applying a direct force to it. The detailed implementation and various modifications described in the first embodiment can also be applied to the third embodiment. In the third embodiment, the cavities 4 and 5 are formed from an elastic material. However, the cavities 4 and 5 do not necessarily need to be made of an elastic material as long as their volumes can be adjusted.

[0092] Furthermore, this third embodiment can be considered an embodiment in which the fourth embodiment described below is applied to the insulating window 10. That is, this insulating window includes a cavity that can change its shape and an insulating material contained in the cavity. The insulating material may be a powder that moves within the cavity as the shape of the cavity changes. In this case, the powder insulating material must have high fluidity and, even more preferably, volume retention similar to that of a liquid. In this case, the various modifications described in the fourth embodiment can also be applied to the insulating window 10 of the third embodiment. For example, although not shown, an insulating window whose insulating performance can be adjusted by adjusting the spacing (gap) between a pair of panels 7 may be configured in accordance with the configuration example shown in FIG. 12.

[0093] [Embodiment 4] While Embodiments 1, 2, and 3 are examples in which the present invention is applied to an insulating window 10, the present invention can also be applied to more general insulating components. That is, a more general embodiment of the present invention is an insulating component comprising a cavity whose shape can be changed and an insulating material contained in the cavity, where the insulating material is a powder that moves within the cavity as the shape of the cavity changes. In this case, the insulating material that is a powder is required to have fluidity similar to that of a liquid, and even more preferably, it has volume retention similar to that of a liquid. This makes it possible to provide an insulating component with a simple mechanism for adjusting the insulation.

[0094] A suitable material for a thermal insulator is TIISA. TIISA is made from aerogel 13, which has a three-dimensional network structure with a skeleton formed by clusters 12, which are aggregates of primary particles 11, and is a powder containing fine particles 14, each of which has a three-dimensional network structure with a skeleton formed by the primary particles 11. This structure allows TIISA to achieve the fluidity and volume retention required for a thermal insulator.

[0095] The cavity should be depressurized to a pressure lower than the ambient air pressure. This significantly reduces the thermal conductivity of the insulating material (improving its thermal insulation performance). The improvement in thermal insulation performance is particularly significant when TIISA is used as the insulating material. The skeleton of TIISA accounts for less than 1% of the total volume, and convection is suppressed by evacuating air from the remaining 99% or more of the space (gaps) to reduce the pressure. Because the space (gaps) contributes significantly to thermal conductivity, the improvement in thermal insulation performance due to evacuation is significant. In contrast, the skeleton (solid) of conventional aerogel accounts for a high proportion of the total volume, approximately 5%, and the skeleton (solid) contributes significantly to thermal conductivity. Therefore, even if convection is suppressed by evacuating the gaps, the improvement in thermal insulation performance is relatively small.

[0096] Alternatively, the cavity may be filled with a gas (e.g., carbon dioxide) having a lower thermal conductivity than air. This reduces the thermal conductivity of the insulating member (improving its insulating performance). After the pressure is reduced as described above, the filled state can be maintained for a longer period more easily than maintaining the reduced pressure state. Furthermore, when a liquid (e.g., water) is used as a medium for moving the insulating material, as in the example shown in FIG. 11, a gas (e.g., carbon dioxide) having a lower thermal conductivity than the reduced pressure described above is more suitable.

[0097] FIG. 10 is a schematic cross-sectional view showing an example of the configuration of an insulated container 20 using the insulating member according to this embodiment. The insulated container 20 is composed of an insulating member surrounding the periphery. Specifically, the container 20 includes a sidewall formed by a cavity having a gap 22 between an inner wall 21i and an outer wall 21w, a canopy cavity 21c, and a cavity at the bottom that forms an insulating material storage section 23. The canopy cavity 21c is filled with insulating material 1. A continuous space is formed between the gap 22 between the inner wall 21i and the outer wall 21w and the insulating material storage section 23, and the insulating material 1 is filled in this space. The insulating material storage section 23 is configured to be able to change its volume. By reducing its volume, the insulating material 1 inside is sent into the gap 22 between the inner wall 21i and the outer wall 21w, and by restoring its volume to its original state, the insulating material 1 is collected from the gap 22 to the insulating material storage section 23.

[0098] The mechanism for changing the volume of the thermal material storage section 23 can be configured, for example, by an outer cylinder 27, a piston 28, and an operating rod 29 for pushing in or pulling out the piston 28. To prevent the thermal insulation material 1 inside the thermal material storage section 23 from entering the contact area between the outer cylinder 27 and the piston 28, a bag made of a flexible sheet (not shown) such as latex may be tightly attached from the tip of the outer cylinder 27 to the tip of the piston 28 to separate the inner and outer spaces.

[0099] The portions of the side wall where the insulation material 1 fills the gaps 22 have high insulation performance, while the portions where it does not reach have low insulation performance. For example, the insulation material 1 can be selectively moved to portions where high insulation performance is required, such as where there is a large temperature difference between the inside and outside. It can also be said that the insulation performance of the entire side wall is controlled by the size of the area where the insulation material 1 reaches and fills.

[0100] FIG. 11 is a schematic cross-sectional view showing another example of the configuration of an insulated container 20 using the insulating member according to this embodiment. The insulated container 20 of this example differs from the insulated container 20 of FIG. 10 in that the bottom cavity is composed of an insulating material storage section 23 and a liquid storage section 24. The other components are the same as those of the insulated container 20 of FIG. 10 , so their description will be omitted. The mechanism for adjusting the volume of the bottom cavity can be configured similarly to the mechanism for changing the volume of the insulating material storage section 23 shown in FIG. 10 . However, the bottom cavity contains not only insulating material 1 but also liquid 2. When the volume is changed by this mechanism, it is liquid 2 that is directly moved, while insulating material 1 is pushed by liquid 2 to move. Liquid 2 is exclusive to insulating material 1; that is, liquid 2 is a material that does not mix with insulating material 1 and forms a clear interface. For example, if TIISA is used as insulating material 1, liquid 2 should be a liquid primarily composed of water. Because TIISA is highly hydrophobic, it can move in response to changes in volume via a clear interface without mixing with water. By introducing liquid (water) 2 into the bottom cavity, it is possible to employ known means for suppressing water leakage even when a volume adjustment mechanism such as the outer cylinder 27 and piston 28 is provided. In other words, because a liquid (e.g., water) is used as a medium for moving the insulating material, there is an advantage in that leakage can be suppressed even if there are moving parts, and the degree of freedom in designing the volume adjustment mechanism can be increased.

[0101] Figure 12 is a schematic cross-sectional view showing another example of the configuration of an insulated container using the insulating member according to this embodiment. While the configuration examples shown in Figures 10 and 11 have a volume adjustment mechanism in the bottom cavity, the insulating performance can be adjusted by changing the thickness of the insulating material 1 filled in the cavity in the side wall portion. The cavity in the side wall portion is formed by a gap between the inner wall 21i and the outer wall 21w. The bottom of the container 20 has a double structure consisting of a floor surface 21f and a bottom surface 21b, and the insulating material 1 is filled in the gap. The canopy cavity 21c is connected to the gap between the inner wall 21i and the outer wall 21w, allowing the insulating material 1 to move freely. By expanding the outer wall 21w outward, the gap between the inner wall 21i and the outer wall 21w is maximized, maximizing the insulating performance (Figure 12(a)). By pushing the outer wall 21w toward the inner wall 21i to narrow the gap, the filled insulation material 1 is pushed into the cavity 21c of the canopy, and the thickness of the insulation material 1 filled in the cavity of the side wall becomes thinner, resulting in a decrease in insulation performance (Fig. 12(b)). Note that it is preferable to incline the inner side of the cavity 21c of the canopy toward the gap of the side wall. The angle of inclination is set to a value large enough to allow the insulation material 1 to move into the gap of the side wall under its own weight.

[0102] Adjusting insulation performance is expected to have a variety of applications. For example, liquid hydrogen tanks used to supply hydrogen to fuel cell vehicles require proper management of their internal pressure. If the internal pressure is too high, the tank must be vented to prevent it from bursting, resulting in the waste of hydrogen inside the container. On the other hand, if the internal pressure is too low, it becomes impossible to properly fill the fuel cell vehicle with hydrogen from the tank. Similar internal pressure adjustment is also required for tanks in tankers that transport liquid hydrogen over long distances.

[0103] The invention made by the inventor has been specifically described above based on an embodiment, but it goes without saying that the invention is not limited thereto and can be modified in various ways without departing from the spirit of the invention.

[0104] The present invention can be suitably used for a heat insulating member that allows the insulating portion to be changed, and can further be suitably applied to a heat insulating window that can be switched between a transparent state and a light-blocking / heat-blocking state.

[0105] REFERENCE SIGNS LIST 1 Insulation material 2 Liquid (water) 3 Compression mechanism 4 Lower elastic cavity 5 Upper elastic cavity 6 Frame 7 Panel 8 Space 10 Insulation window 11 Primary particles 12 Secondary particles (aggregates, clusters of primary particles) 13 Aerogel particles (particles with a skeleton formed by secondary particles) 14 Fine particles with a skeleton formed by primary particles (e.g., TIISA) 20 Insulation container 21 Cavity 21i, 21w, 21f, 21b Inner wall, outer wall, floor, bottom of insulated container 21c Cavity in the canopy part of the insulated container 22 Gap (space) 23 Insulation material storage section 24 Liquid storage section, volume adjustment mechanism using liquid as a medium 27 Outer cylinder 28 Piston 29 Operating rod 90 Dynamic angle of repose measurement device 91 Sample 92 Glass container 93 Roller 96 Elastic tube 97 Compression Block

Claims

1. An insulating window comprising a pair of panels, a space between the pair of panels, an insulating material that can be filled into the space, and a mechanism that can move the insulating material into the space to fill it and move it out of the space to remove it, The heat insulating material is made of an aerogel having a three-dimensional network structure in which a skeleton is formed of secondary particles, which are an aggregate of primary particles, and includes fine particles having a three-dimensional network structure in which a skeleton is formed of primary particles generated by breaking down the secondary particles, The fine particles constituting the heat insulating material are characterized in that 50% or more of their volume are dispersed with a particle diameter of 0.1 μm or more and 1.0 μm or less as a mode. Insulated windows.

2. In claim 1, The mechanism is a mechanism capable of moving a liquid in contact with the insulating material in order to move the insulating material. Insulated windows.

3. 3. The method according to claim 2, wherein the heat insulating material is hydrophobic and the liquid is mainly composed of water. Insulated windows.

4. In claim 2, the mechanism includes an elastic cavity below the space that can accommodate the insulating material and the liquid, and a compression mechanism that can increase and decrease a volume of the elastic cavity; The mechanism moves the insulating material from the elastic cavity to the space by decreasing a volume of the elastic cavity with the compression mechanism, and moves the insulating material from the space into the elastic cavity by increasing a volume of the elastic cavity with the compression mechanism. Insulated windows.

5. In claim 2, the mechanism includes an upper elastic cavity capable of accommodating the insulating material on an upper side of the space, a lower elastic cavity capable of accommodating the liquid on a lower side of the space, and a compression mechanism capable of increasing and decreasing a volume of the lower elastic cavity, The mechanism comprises: a compression mechanism for reducing a volume of the lower elastic cavity, thereby moving the liquid from the elastic cavity to the space and moving the insulating material from the space to the upper elastic cavity; increasing a volume of the lower elastic cavity by the compression mechanism, thereby moving the liquid from the space into the lower elastic cavity and moving the insulating material from the upper elastic cavity to the space; Insulated windows.

6. A cavity capable of changing its shape and a heat insulating material contained in the cavity, the heat insulating material being a powder that moves within the cavity as the shape changes; The heat insulating material is made of an aerogel having a three-dimensional network structure in which a skeleton is formed of secondary particles, which are an aggregate of primary particles, and contains fine particles having a three-dimensional network structure in which a skeleton is formed of primary particles generated by breaking down the secondary particles. Thermal insulation material.

7. In claim 6, The heat insulating material has fluidity and a volume retention performance that maintains the volume before and after the change in the shape of the cavity. Thermal insulation material.

8. In claim 6, The pressure inside the cavity is reduced below the outside air pressure. Thermal insulation material.

9. In claim 6, The cavity is filled with a gas having a lower thermal conductivity than air. Thermal insulation material.

10. In claim 6, The cavity further contains a liquid that is exclusive to the insulating material. Thermal insulation material.

11. 7. The method of claim 6, wherein the insulating material is hydrophobic. The cavity further contains water. Thermal insulation material.

12. In claim 6, The cavity has one or more pairs of panels and a thermal insulation housing, Each of the one or more pairs of panels has a gap therein capable of receiving the insulating material therein; The insulation material storage section stores the insulation material, and the volume of a space continuous with the gap is changed to push the insulation material into the gap between the panels or to recover the insulation material from the gap between the panels. Thermal insulation material.

13. In claim 10, The cavity has one or more pairs of panels, a heat insulating material storage section, and a liquid storage section; Each of the one or more pairs of panels has a gap therein capable of receiving the insulating material therein; The heat insulating material storage section has a space continuous with the gap and can store the heat insulating material in the space, the liquid storage section stores the liquid, and a volume of a space connected to the gap is changed to move the liquid, and the insulating material is pushed out into the gap between the panels or collected from the gap between the panels. Thermal insulation material.