Composite boards, composite panels, and methods for manufacturing the same.

Abstract

To provide a member that contains a low-density gel body such as aerogel and is suitable for application to a wall material.SOLUTION: A member provided is a composite board including a substrate and a low-density gel body that is composited with the substrate, and has a flexural modulus of 4.0 MPa or more and a flexural fracture strain of 0.05 or more. The composite board may have a flexural strength of 2.5 MPa or more. The substrate may include at least one selected from the group consisting of glass wool and rock wool.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a composite board, a composite panel, a method for manufacturing the composite board, and a method for manufacturing the composite panel.

Background Art

[0002] As an outer wall material for a building, a sandwich panel in which a heat insulation foam as a core material is sandwiched between steel plates is known (for example, Patent Document 1). Although there is no description about a wall material, Patent Document 2 discloses a silica aerogel block as a material having a low thermal conductivity.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, there has been a demand for energy conservation, and there is a strong demand for improving the heat insulation properties of wall materials including outer walls. Focusing on the low thermal conductivity, it is conceivable to apply the aerogel block of Patent Document 2 to a wall material. However, according to the study by the present inventors, the above block is brittle and difficult to apply to a wall material as it is.

[0005] An object of the present invention is to provide a member suitable for application to a wall material while including a low-density gel body such as aerogel.

Means for Solving the Problems

[0006] The present inventors completed the present invention by examining the composite of a low-density gel body with a base material and paying attention to the mechanical properties suitable for a wall material.

[0007] The present invention The material comprises a substrate and a low-density gel compounded with the substrate. The present invention provides a composite board having a flexural modulus of 4.0 MPa or higher and a flexural fracture strain of 0.05 or higher.

[0008] Furthermore, the present invention, The composite board and, A surface layer disposed on at least one surface of the composite board, A composite panel is provided that includes the following features.

[0009] Furthermore, the present invention, A method for manufacturing the composite board, The process involves immersing the substrate in a solution containing a sol of a precursor compound having a hydrolyzable functional group, and allowing the sol to gel while the gelation process is carried out to form a wet gel. The wet gel is dried to form the composite board containing the substrate and the low-density gel body compounded with the substrate, The present invention provides a method for manufacturing composite boards, including the following:

[0010] Furthermore, the present invention, A method for manufacturing the composite panel, The present invention provides a method for manufacturing a composite panel, which includes arranging a surface layer on at least one surface of the composite board. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a member that is suitable for application to wall materials, even while containing a low-density gel. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic perspective view showing an example of the composite board of the present invention, and a partial enlarged view showing an enlarged portion thereof. [Figure 2A] This is a schematic perspective view showing an example of the composite panel of the present invention. [Figure 2B]This is a cross-sectional view showing the cross-section 2B-2B of the composite panel in Figure 2A. [Figure 3] This graph shows the stress-strain curve obtained by a three-point bending test in the example. [Modes for carrying out the invention]

[0013] A composite board according to the first aspect of the present invention is The material comprises a substrate and a low-density gel compounded with the substrate. It has a flexural modulus of 4.0 MPa or higher and a flexural fracture strain of 0.05 or higher.

[0014] In a second embodiment of the present invention, for example, the composite board according to the first embodiment has a bending strength of 2.5 MPa or more.

[0015] In a third embodiment of the present invention, for example, in a composite board according to the first or second embodiment, the substrate is a porous material, and the low-density gel body is present inside the voids of the substrate.

[0016] In a fourth aspect of the present invention, for example, in a composite board according to any one of the first to third aspects, the substrate includes at least one selected from the group consisting of glass wool and rock wool.

[0017] In a fifth embodiment of the present invention, for example, in a composite board according to any one of the first to fourth embodiments, the density of the substrate is 32 kg / m³ 3 That's all.

[0018] In a sixth aspect of the present invention, for example, in a composite board according to any one of the first to fifth aspects, the low-density gel has a backbone containing polyorganosiloxane chains.

[0019] In the seventh aspect of the present invention, for example, in the composite board according to the sixth aspect, the polyorganosiloxane chain has a T unit as its main constituent unit.

[0020] In the eighth embodiment of the present invention, for example, a composite board according to any one of the first to seventh embodiments further includes a filler.

[0021] In the ninth aspect of the present invention, for example, in the composite board according to the eighth aspect, the filler is at least one selected from the group consisting of metal hydroxide particles and metal oxide particles.

[0022] In the tenth embodiment of the present invention, for example, a composite board according to any one of the first to ninth embodiments is for use as a wall material for a building.

[0023] A composite panel according to the 11th aspect of the present invention is A composite board according to any one of the first to tenth embodiments, A surface layer disposed on at least one surface of the composite board, It is equipped with.

[0024] In a twelfth aspect of the present invention, for example, the composite panel according to the eleventh aspect is for use as a wall material for buildings.

[0025] A method for manufacturing a composite board according to a thirteenth aspect of the present invention is: A method for manufacturing a composite board according to any one of the first to tenth embodiments, The process involves immersing the substrate in a solution containing a sol of a precursor compound having a hydrolyzable functional group, and allowing the sol to gel while the gelation process is carried out to form a wet gel. The wet gel is dried to form the composite board containing the substrate and the low-density gel body compounded with the substrate, Includes.

[0026] In the 14th aspect of the present invention, for example, in the method for manufacturing a composite board according to the 13th aspect, the precursor compound is a silicon compound.

[0027] In a 15th aspect of the present invention, for example, in the method for manufacturing a composite board according to the 13th or 14th aspect, the wet gel is dried by atmospheric pressure drying.

[0028] A method for manufacturing a composite panel according to the 16th aspect of the present invention is: A method for manufacturing a composite panel according to the 11th or 12th embodiment, This includes arranging a surface layer on at least one surface of the composite board.

[0029] [Composite board] An example of a composite board of this embodiment is shown in Figure 1. Figure 1 is a perspective view of the composite board 1 and a partially enlarged view of a part of the composite board 1. The composite board 1 includes a base material 2 and a low-density gel 3. The base material 2 is a board-shaped member. The base material 2 in Figure 1 is composed of fibers 21 intertwined in three dimensions. The base material 2 has voids (spaces) 22 between adjacent fibers 21. The voids 22 extend in the three-dimensional direction inside the base material 2. The low-density gel 3 is present inside the voids 22 of the base material 2. Preferably, the low-density gel 3 fills the inside of the voids 22, in other words, it may extend in the three-dimensional direction inside the base material 2. In one example of a filling configuration, the composite board 1 has a continuous region of low-density gel 3 along its thickness, in other words, from one main surface 23 to the other main surface 24. Separately or in addition to the above, the composite board 1 may have a continuous region of low-density gel 3 extending from one end to the other in its planar direction. The substrate 2 and low-density gel 3 contained within the composite board 1 cannot be separated while maintaining their respective shapes. In other words, the substrate 2 and the low-density gel 3 are composited.

[0030] The composite board 1 has a flexural modulus of 4.0 MPa or higher and a flexural fracture strain of 0.05 MPa or higher. According to the inventors' studies, securing the modulus of elasticity and fracture strain in the bending direction is important for application as a wall material, especially for exterior walls. The modulus of elasticity contributes to the self-supporting nature of the wall material and the reduction of deflection that may occur due to external forces. The fracture strain contributes to securing "toughness" to withstand gusts of wind such as typhoons. The composite board 1, having a flexural modulus of elasticity and flexural fracture strain above a predetermined value, is suitable for application as a wall material, even though it contains a low-density gel body 3.

[0031] The flexural modulus may be 5.0 MPa or higher, 8.0 MPa or higher, 10 MPa or higher, 11 MPa or higher, 12 MPa or higher, 13 MPa or higher, or even 14 MPa or higher. The upper limit of the flexural modulus is, for example, 75 MPa or lower.

[0032] The bending fracture strain may be 0.06 or greater, 0.07 or greater, 0.08 or greater, or even 0.09 or greater. The upper limit of the bending fracture strain is, for example, 0.20 or less.

[0033] The flexural modulus and flexural fracture strain can be determined from the stress-strain curve obtained by a three-point bending test. The specimen is usually a rectangular parallelepiped, with dimensions such as 50 mm in length, 10 mm in width, and 5 mm in thickness. The test speed is 10 mm / min, the distance between supports is 40 mm, and the radius R1 of the indenter tip is 2 mm. For the support base, the cross-sectional shape along the length of the specimen is semicircular, with a radius R2 of 2 mm. The flexural modulus is evaluated using the tangential method. The test is conducted at room temperature (25 ± 5 °C).

[0034] The composite board 1 may have a flexural strength of 2.5 MPa or more. The flexural strength may be 2.7 MPa or more, 3.0 MPa or more, 3.2 MPa or more, 3.5 MPa or more, 3.7 MPa or more, 3.8 MPa or more, and further 4.0 MPa or more. The upper limit of the flexural strength is, for example, 20 MPa or less. According to the study by the inventors, the flexural strength can contribute to the improvement of both self-supporting property and adhesiveness. The composite board 1 further having the flexural strength within the above range is particularly suitable for application to wall materials. The flexural strength can be specified by the above three-point bending test.

[0035] The fiber 21 may be a short fiber. Examples of the short fiber are glass wool and mineral fiber. An example of the mineral fiber is rock wool. The base material 2 may contain at least one selected from the group consisting of glass wool and rock wool. The base material 2 may be a glass wool board or a rock wool board. The base material 2 may not be mainly composed of resin and may not contain resin fiber as the main component.

[0036] Including the example of FIG. 1, the base material 2 may be a porous material. At this time, a low-density gel body 3 may be present inside the pores 22 of the base material 2. Examples of the mode in which the low-density gel body 3 exists are as described above in the description of FIG. 1.

[0037] The density of the base material 2 may be 32 kg / m 3 or more, 35 kg / m 3 or more, 37 kg / m 3 or more, 40 kg / m 3 or more, 45 kg / m 3 or more, 50 kg / m 3 or more, 55 kg / m 3 or more, 60 kg / m 3 or more, 65 kg / m 3 or more, 70 kg / m 3 or more, 75 kg / m 3 or more, 80 kg / m 3 or more, 85 kg / m 3 or more, 90 kg / m 3 or more, and further 95 kg / m 3It may be greater than that. There is no upper limit to the density, but for example, 300 kg / m³ 3 The following is true: 250 kg / m 3 Furthermore, 200 kg / m 3 The following may also apply. According to the inventors' studies, the density of the base material 2 can contribute to improving both the self-supporting properties and the toughness of the composite board 1. The composite board 1, including the base material 2 having the above density, is particularly suitable for application as a wall material. The base material 2 may be a glass wool board or a rock wool board having a density within the above range.

[0038] The thickness of the base material 2 is, for example, 10 mm or more, and may be 15 mm or more, 20 mm or more, 22 mm or more, 25 mm or more, 27 mm or more, or even 30 mm or more. The upper limit of the thickness is, for example, 300 mm or less, and may be 250 mm or less, 200 mm or less, 150 mm or less, 130 mm or less, 110 mm or less, or even 100 mm or less. The use of a base material 2 with a thickness of 30 mm or more can contribute, for example, to improving the fire resistance performance of the wall material.

[0039] Low-density gel 3, as its name suggests, is a low-density solid-phase gel. The density of low-density gel 3 is typically 0.5 g / cm³. 3 The following is true: 0.4 g / cm³ 3 Below, 0.3g / cm 3 Below, 0.2g / cm 3 The following is even more accurate: 0.15 g / cm³ 3 The following is also acceptable. There is no lower limit to the density, but for example, 0.05 g / cm³. 3 That's all.

[0040] The low-density gel 3 typically has a gel skeleton (hereinafter referred to as the skeleton) and pores. The average diameter of the pores is typically 1000 nm or less, but may be 700 nm or less, 500 nm or less, 300 nm or less, or even 100 nm or less. There is no lower limit to the average diameter, but for example it is 10 nm or more. The low-density gel 3 may have a network structure in which the skeleton and pores are intertwined in three dimensions. The average diameter of the pores can be determined as the median diameter (d50) by measuring the pore distribution using methods such as nitrogen gas adsorption.

[0041] The porosity of the low-density gel 3 is, for example, 70-99%, and may be 80-98%, 85-97%, or even 90-95%. The porosity can be evaluated by laser confocal microscopy.

[0042] The thermal conductivity of the low-density gel 3 is, for example, 0.001 to 0.03 W / mK, and may also be 0.005 to 0.025 W / mK, or even 0.01 to 0.02 W / mK. The thermal conductivity can be evaluated in accordance with the provisions of Japanese Industrial Standards (hereinafter referred to as JIS) A1412 (steady-state method). The value shall be taken at 25°C. The same applies to the thermal conductivity of the composite board 1.

[0043] The low-density gel 3 may have a backbone containing polyorganosiloxane chains. Having a backbone containing polyorganosiloxane chains can contribute to improving the bending properties of the composite board 1.

[0044] A polyorganosiloxane chain is a type of polysiloxane chain containing siloxane bonds. A polysiloxane chain may or may not have branching of siloxane bonds originating from the silicon (Si) atoms constituting the chain. Those skilled in the art are well aware of the notation for the constituent units of a polysiloxane chain as Q units (zero organo groups bonded to the Si atom), T units (one organo group bonded to the Si atom), and D units (two organo groups bonded to the Si atom). The polyorganosiloxane chain that the backbone of the low-density gel 3 may have includes T units and / or D units, preferably T units, in which organo groups are bonded to the Si atoms. Organo groups are non-polymerizable organic groups and are typically monovalent. Examples of organo groups include alkyl groups, alkenyl groups, and alkynyl groups. The number of carbon atoms in these groups may be, for example, 1 to 4, 1 to 3, or even 1 to 2. The organo group may be an alkyl group, and examples of alkyl groups are the methyl group and the ethyl group.

[0045] The polyorganosiloxane chain may have T units as its main constituent units. The polyorganosiloxane chain does not have to have Q units as its main constituent units; in other words, the low-density gel 3 does not have to be silica-based. Having T units as the main constituent units can contribute to improving the bending properties of the composite board 1. In this specification, the main constituent unit means a unit that accounts for 50 mol% or more of all constituent units that make up the chain. The proportion of T units may be 60 mol% or more, 65 mol% or more, 70 mol% or more, 75 mol% or more, 80 mol% or more, or even 85 mol% or more. The upper limit of the proportion of T units may be, for example, 100 mol% or less, 95 mol% or less, 90 mol% or less, 85 mol% or less, or even 80 mol% or less.

[0046] The polyorganosiloxane chain may have Q units and / or D units. An example of the composition of the polyorganosiloxane chain is expressed by the proportions (in mole%) of each unit of Q, T, and D, where Q:T:D = 0-30:60-100:0-20, or 0-20:70-90:0-15.

[0047] The low-density gel 3 may be an aerogel, a xerogel, or a cryogel. The difference in names between aerogel, xerogel, and cryogel stems from the difference in drying methods used to form a solid-phase low-density gel from a wet gel. Low-density gels formed by supercritical drying are generally called aerogels, low-density gels formed by atmospheric pressure drying are called xerogels, and low-density gels formed by freeze-drying are called cryogels.

[0048] The composite board 1 may contain further materials other than the base material 2 and the low-density gel 3. An example of a further material is a filler. The composite board 1 may further contain a filler. The filler may be at least one selected from the group consisting of metal hydroxide particles, metal oxide particles, metal salt particles, and carbon particles. The inclusion of fillers such as metal hydroxide particles, metal oxide particles, metal salt particles, and carbon particles, particularly metal hydroxide particles, can contribute to improving the fire resistance performance of the composite board 1. The composite board 1 may contain one or more types of fillers.

[0049] Examples of metal hydroxides that can constitute a filler include aluminum hydroxide, magnesium hydroxide, iron hydroxide, and copper(II) hydroxide. Examples of metal oxides that can constitute a filler include iron(III) oxide, iron(II) oxide, manganese ferrite, MnO, MnO2, NiO, SnO, Ag2O, Bi2O3, titanium oxide, iron titanium oxide (e.g., ilmenite), aluminum oxide, zirconium silicate, zirconium oxide, and chromium oxide. Examples of metal salts that can constitute a filler include calcium sulfate (typically dihydrate) and aluminum sulfate (typically hydrate). An example of carbon that can constitute a filler is carbon black. The filler is preferably aluminum hydroxide. According to our studies, aluminum hydroxide has an endothermic effect due to the release of crystal water at around 250°C, making it particularly suitable for combination with low-density gel 3 having polyorganosiloxane chains that typically decompose at 300°C to 400°C.

[0050] The average particle size of the filler is, for example, 0.1 to 100 μm, but may also be 5.0 to 20 μm, 5.0 to 10 μm, or 10 to 20 μm. The average particle size of the filler can be determined as the median diameter by laser diffraction particle size distribution measurement.

[0051] The amount of filler in the composite board 1 is, for example, 10 to 100 parts by weight, with the weight of the base material 2 and the low-density gel body 3 being 100 parts by weight, and may also be 20 to 70 parts by weight, 25 to 60 parts by weight, 30 to 50 parts by weight, or even 30 to 40 parts by weight.

[0052] As long as the composite board 1 has a flexural modulus of 4.0 MPa or higher and a flexural fracture strain of 0.05 or higher, the composition of the base material 2 and the low-density gel body 3 is not limited to the above example.

[0053] The thermal conductivity of composite board 1 in the thickness direction is, for example, 0.005 to 0.050 W / mK, and may also be 0.008 to 0.035 W / mK, 0.01 to 0.03 W / mK, 0.01 to 0.027 W / mK, or even 0.015 to 0.025 W / mK. Composite board 1 can be an insulating board. For reference, the thermal conductivity of commercially available glass wool boards is at least around 0.028 W / mK, and the thermal conductivity of rock wool boards is at least around 0.045 W / mK.

[0054] The density of composite board 1 is, for example, 100-350 kg / m³. 3 It may also be 150-340 kg / m 3 , 175~325 kg / m 3 , 200-300 kg / m 3 , 225~275 kg / m 3 That's fine.

[0055] The water absorption capacity of composite board 1 is, for example, 0.1 to 3 g / cm³. 2 Therefore, 0.2~2.5 g / cm³ 3 , 0.3~2g / cm³ 2 , 0.4~1.5 g / cm 2 Furthermore, 0.5~1.3g / cm³ 2This may also be the case. Note that the water absorption capacity of commercially available glass wool boards and rock wool boards is typically 30 g / cm³. 2 This concludes the report. The composite board 1, with its low water absorption, is particularly suitable for application to exterior walls. The water absorption can be measured in accordance with the provisions of JIS A9521. However, the shape of the test specimen shall be a rectangular parallelepiped with a length of 50 mm, a width of 50 mm, and a thickness of 10 mm.

[0056] The composite board 1 may have performance equivalent to that of a fire-resistant structure under the Building Standards Act. For example, when the composite board 1 is 30 mm thick, it may have heat-shielding and / or flame-retardant properties when heated for 30 minutes on one main surface based on the standard heating curve specified in ISO 834, and left for 1 hour and 30 minutes after heating (three times the heating time). Heat-shielding means that the temperature rise of the unheated surface, based on the temperature before heating, is kept below an average of 140K and below a maximum of 180K. Flame-retardant means that there is no emission of flames on the unheated surface for more than 10 seconds.

[0057] The shape of the composite board 1 is typically a square or rectangle when viewed perpendicular to its main surface. However, the shape is not limited to the above examples. The composite board 1 may be processed into a desired shape by mechanical processing such as cutting or shaping a composite board 1 that has been manufactured in a rectangular shape, for example.

[0058] The thickness of the composite board 1 is, for example, 10 mm or more, and may be 15 mm or more, 20 mm or more, 22 mm or more, 25 mm or more, 27 mm or more, or even 30 mm or more. The upper limit of the thickness is, for example, 300 mm or less, and may be 250 mm or less, 200 mm or less, 150 mm or less, 130 mm or less, 110 mm or less, or even 100 mm or less.

[0059] The area of ​​composite board 1 is 0.1 m². 2 More than 0.5m 2 Above 1m 2 More than 5m 2 More than 10m 2 More than 20m 2 Over 25m 2 In addition to the above, 50m2 It may be greater than or equal to this. There is no upper limit on the area, but for example, 80m 2 The following applies: The longest side of the composite board 1 may be 0.1m or more, 0.5m or more, 1m or more, 2m or more, 3m or more, 4m or more, 5m or more, or even 8m or more. There is no upper limit to the longest side, but for example, it should be 12m or less. The composite board 1 may be self-supporting even when it has the above area.

[0060] An example of the application of composite board 1 is as a wall material for buildings. In other words, composite board 1 may be used as a wall material for buildings. The wall material may be an exterior wall or an interior wall, but composite board 1, which may have low thermal conductivity, is particularly suitable for application to exterior walls. When applying composite board 1 to a wall material, it may be embedded in the wall material as an insulating board, or it may be applied as a wall material in combination with other components such as decorative materials. It can also be applied to a wall material as a composite panel using composite board 1 as a core material. However, the applications of composite board 1 are not limited to the above examples.

[0061] [Manufacturing method for composite boards] The manufacturing method for composite board 1 is described below. In the following example, a low-density gel 3 is formed by the progress of a sol-gel reaction with a precursor compound. However, the manufacturing method for composite board 1 is not limited to the following example.

[0062] The manufacturing method of this embodiment includes a gelling step, in which a substrate 2 is immersed in a solution containing a sol of a precursor compound having a hydrolyzable functional group (hereinafter referred to as the sol solution), and the gelling of the sol is allowed to proceed to form a wet gel, and a drying step, in which the wet gel is dried to form a composite board 1 containing the substrate 2 and a low-density gel body 3 compounded with the substrate 2.

[0063] (Gelation process) In the manufacturing method of this embodiment, the low-density gel 3 is produced by forming a wet gel, which is a gelled product of the precursor compound. The wet gel can be formed by solifying the precursor compound by a hydrolysis reaction, and further gelling the solified precursor compound by a polycondensation reaction. Solification and gelation may proceed independently or in combination. If they proceed independently, solification and gelation may proceed continuously, or there may be a time interval between the completion of solification and the start of gelation. In addition, in the manufacturing method of this embodiment, gelation is carried out while the substrate 2 is immersed in the solification solution. However, immersion of the substrate 2 can be performed at any timing, regardless of the degree of solification of the precursor compound. In other words, the substrate 2 may be immersed in the solution before solification (hereinafter referred to as the precursor solution), or in the solification solution in which solification has partially or completely progressed. In a typical example, the substrate 2 is immersed when solification has partially or completely progressed.

[0064] The immersion of the substrate 2 is preferably carried out so that the solution penetrates into the interior of the substrate 2. If the substrate 2 is a porous material, the immersion may be carried out so that the solution penetrates into the pores of the substrate 2. In a preferred example, the substrate 2 is placed in a container such as a tray or pad, and the solution is poured into it. A container corresponding to the desired shape and size of the low-density gel 3 may be selected, and the gelation may proceed as is using the container as a mold. To aid penetration, mechanical vibration or ultrasound may be added to at least one selected from the group consisting of the container, the solution, and the substrate 2.

[0065] 1. Solification The hydrolyzable functional group of the precursor compound is, for example, an alkoxy group having 1 to 4 carbon atoms. However, the functional group is not limited to the above example. The functional group may be a methoxy group or an ethoxy group. Methoxy and ethoxy groups are particularly suitable for stable hydrolysis and polycondensation reactions.

[0066] The precursor compound may be a silicon compound. An example of a silicon compound is alkoxysilane. Examples of silicon compounds that can constitute a Q unit after the gelation process are tetramethoxysilane (TMOS), tetraethoxysilane, tetrapropoxysilane, and tetraisopropoxysilane. Examples of silicon compounds that can constitute a T unit are methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, propyltriethoxysilane, pentyltriethoxysilane, hexyltriethoxysilane, and octyltriethoxysilane. Examples of silicon compounds that can constitute a D unit are dimethyldimethoxysilane, diethyldimethoxysilane, and diisobutyldimethoxysilane. However, the precursor compound and silicon compound are not limited to the above examples.

[0067] Solification is typically carried out with respect to the precursor solution. The precursor solution contains one or more precursor compounds. Depending on the desired composition of the low-density gel 3, the precursor solution may contain two or more precursor compounds. For example, the precursor solution may contain a silicon compound that can constitute T units, and may further contain a silicon compound that can constitute Q units and / or a silicon compound that can constitute D units. The content of T units, Q units, and D units in the low-density gel 3 can be controlled by the type and content of the precursor compounds contained in the precursor solution.

[0068] The content of the precursor compound in the precursor solution, if two or more types are present, is, for example, 10 to 70% by volume, but may also be 20 to 60% by volume, or even 30 to 50% by volume.

[0069] The solvent in the precursor solution is not limited as long as the hydrolysis reaction of the precursor compound can proceed. Examples of solvents include water, methanol, ethanol, 2-propanol, benzyl alcohol, formamide, N,N-dimethylformamide, and dimethyl sulfoxide. The solvent may also be a mixture of these. Examples of preferred solvents are water, methanol, ethanol, 2-propanol, and mixtures thereof. The solvents exemplified above are also suitable for the polycondensation reaction.

[0070] The precursor solution may contain a catalyst (solification catalyst) that promotes the hydrolysis reaction. Examples of solification catalysts are acids. Examples of acid catalysts include inorganic acids such as hydrochloric acid, nitric acid, and sulfuric acid; and organic acids such as formic acid, acetic acid, and oxalic acid. Organic acids are particularly suitable for more stable hydrolysis reactions. The precursor solution may contain one or more acid catalysts.

[0071] The concentration of the solification catalyst added to the precursor solution is, for example, 0.0001 mol / L to 0.1 mol / L relative to the total solution, and may also be 0.0005 mol / L to 0.05 mol / L, or 0.001 mol / L to 0.01 mol / L.

[0072] As long as a low-density gel 3 is formed, the precursor solution may contain other materials besides those described above.

[0073] The temperature for solification is, for example, 0 to 120°C, or it may be 0 to 60°C. The time required for solification to be completed varies depending on the composition of the precursor solution, but for example, it may be 0.5 to 1.5 hours, or it may be 0.75 to 1 hour.

[0074] 2. Gelation Gelation is carried out while the substrate 2 is immersed in a solution containing a sol of the precursor compound (solification solution). The solification solution may also contain the precursor compound before it is solified.

[0075] The solvents used for the sol-forming solution are the same as those used for the precursor solution. The same solvent may be used for both sol-forming and gel-forming.

[0076] The solubilized solution may contain a catalyst (gelling catalyst) that facilitates the polycondensation reaction. An example of a gelling catalyst is a base. Examples of base catalysts include ammonia; ammonium compounds such as ammonium hydroxide, ammonium fluoride, ammonium chloride, and ammonium bromide; alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, and cesium hydroxide; basic sodium phosphate salts such as sodium metaphosphate, sodium pyrophosphate, and sodium polyphosphate; allylamine, diallylamine, triallylamine, isopropylamine, diisopropylamine, ethylamine, diethylamine, triethylamine, 2-ethylhexylamine, 3-ethoxypropylamine, diisobutylamine, and 3-(diethylamino)propylamine. Aliphatic amines such as pyramine, di-2-ethylhexylamine, 3-(dibutylamino)propylamine, tetramethylethylenediamine, t-butylamine, sec-butylamine, propylamine, 3-(methylamino)propylamine, 3-(dimethylamino)propylamine, 3-methoxyamine, dimethylethanolamine, methyldiethanolamine, diethanolamine, and triethanolamine; nitrogen-containing heterocyclic compounds such as morpholine, N-methylmorpholine, 2-methylmorpholine, piperazine and its derivatives, piperidine and its derivatives, and imidazole and its derivatives. The solubilized solution may contain one or more base catalysts.

[0077] The base catalyst may be a compound that produces a basic substance upon heating. This compound may be added to the precursor solution beforehand. In this case, the solution may be heated at any stage during the solification process, for example, after solification is complete, to generate the basic substance and thereby allow the polycondensation reaction to proceed. Examples of such compounds include nitrogen compounds. Examples of nitrogen compounds include amide compounds such as urea, formamide, N-methylformamide, N,N-dimethylformamide, acetamide, N-methylacetamide, and N,N-dimethylacetamide; and heterocyclic compounds such as hexamethylenetetramine. Among these, urea is particularly suitable from the viewpoint of increasing the rate of gelation. Urea typically produces ammonia when the solution temperature reaches approximately 55°C or higher.

[0078] The amount of gelling catalyst in the sol solution is, for example, 0.5 to 10 parts by weight per 100 parts by weight of the precursor compound and its sol, and may also be 1 to 5 parts by weight. When using a compound that produces a basic substance upon heating, the amount of the compound may be adjusted so that the amount of the produced basic substance falls within the above range.

[0079] The gelation temperature can be, for example, 0 to 120°C, or 0 to 60°C. The time required for gelation to be completed varies depending on the composition of the solubilating solution, but can be, for example, 1 to 120 hours, or 1 to 72 hours.

[0080] As long as a low-density gel 3 is formed, the solving solution may contain other materials besides those described above.

[0081] Other materials include surfactants. Surfactants can contribute to the formation of the gel skeleton and pores through the progression of the phase separation process. Examples of surfactants include nonionic surfactants, anionic surfactants, and cationic surfactants. An example of a nonionic surfactant is a nonionic triblock copolymer consisting of ethylene oxide and propylene oxide chains. Examples of the above triblock copolymers are Pluronic® F-127, L-64, P-105, P-94, and F-68. Examples of cationic surfactants are cetyltrimethylammonium bromide and cetyltrimethylammonium chloride. However, surfactants are not limited to the above examples.

[0082] The amount of surfactant added is, for example, 0.001 to 100 parts by weight per 100 parts by weight of the precursor compound and its sol, and may also be 0.01 to 90 parts by weight, or even 0.1 to 80 parts by weight.

[0083] The surfactant may be added to the precursor solution beforehand, as long as it allows for the formation of the low-density gel 3.

[0084] Another example of other materials is additives such as fillers. Additives may be pre-mixed into the precursor solution, as long as the formation of the low-density gel 3 is possible.

[0085] 3. Burn-in In the manufacturing method of this embodiment, the wet gel formed by gelation may be aged (matured). Aging can contribute to improving the final polycondensation ratio. The aging temperature may be, for example, 0 to 120°C, or 60 to 100°C. The aging time may be, for example, 24 to 120 hours, or 48 to 72 hours.

[0086] (drying process) In the drying process, the wet gel formed in the gelation process is dried to form a low-density gel body 3. Known drying methods for obtaining low-density gel bodies can be applied to the wet gel. Examples of drying methods include supercritical drying, atmospheric pressure drying, and freeze-drying.

[0087] Supercritical drying uses a fluid in a supercritical state. Examples of fluids include carbon dioxide fluid, methanol fluid, and water fluid. Solvent replacement of the wet gel may be performed before supercritical drying.

[0088] In the manufacturing method of this embodiment, the wet gel may be dried by atmospheric pressure drying. The temperature for atmospheric pressure drying is not limited, but for example it may be 20 to 120°C, or 40 to 60°C. Before atmospheric pressure drying, solvent replacement of the wet gel may be performed.

[0089] Solvent substitution may be performed to remove catalysts or surfactants, remove by-products, or suppress damage to the low-density gel 3 during drying. If multiple objectives are to be addressed, the solvent substitution may be performed multiple times with different solvents for each objective.

[0090] Examples of solvents used to remove catalysts and additives include alcohols such as methanol, ethanol, n-propanol, isopropanol, and 1-butanol. A mixture of two or more solvents may also be used.

[0091] Examples of solvents used to suppress damage to the low-density gel 3 during drying include solvents with low surface tension, such as solvents with a surface tension of 45 mN / m or less at 20°C. Examples of such solvents include dimethyl sulfoxide, cyclohexane, isopropanol, heptane, and pentane. A mixture of two or more solvents may also be used. The surface tension may be 40 mN / m or less, 35 mN / m or less, 30 mN / m or less, 25 mN / m or less, 20 mN / m or less, or even 15 mN / m or less. The lower limit of the surface tension is, for example, 5 mN / m or more.

[0092] The manufacturing method of this embodiment may include any steps other than those described above, as long as a low-density gel 3 is obtained. An example of such a step is a washing step.

[0093] [Composite Panel] An example of a composite panel of this embodiment is shown in Figures 2A and 2B. Figure 2B is a cross-sectional view showing the cross section 2B-2B of Figure 2A. The composite panel 11 in Figures 2A and 2B comprises a composite board 1 of this embodiment, a surface material 12 arranged on one main surface of the composite board 1, and a back material 13 arranged on the other main surface. The composite panel 11 further comprises first fillers 15A, 15B, a second filler 16, and a sealing material 17. The first fillers 15A, 15B and the second filler 16 are members that have the function of filling the gaps in the fitting portions between adjacent composite panels 11 when a plurality of composite panels 11 are arranged to form a wall of a building. The strength and shape retention of the composite panel 11 as a wall material are mainly provided by the composite board 1. In other words, the composite board 1 is the main component of the composite panel 11. The composite board 1 may occupy 90% or more, preferably 95% or more, 98% or more, and even 99% or more, of the volume of the composite panel 11. Furthermore, the composite board 1 may occupy 90% or more, preferably 95% or more, 98% or more, and even 99% or more, of the weight of the composite panel 11. The composite panel 11 in Figures 2A and 2B is a sandwich panel comprising the composite board 1 as a core material.

[0094] The surface material 12 and back material 13 are usually in sheet form and can function as surface layers of the composite panel 11. Various metals, resins, and composite materials can be used for the surface material 12 and back material 13. Examples of metals include steel, aluminum, and stainless steel. Examples of resins include polycarbonate, polypropylene, and polyethylene. An example of a composite material is fiber-reinforced plastic (FRP). The use of aluminum, resins, and composite materials can contribute to reducing the weight of the composite panel 11. Water-resistant materials may be used for the surface material 12 and / or back material 13. A composite panel 11 with a water-resistant surface layer is particularly suitable for application to exterior walls. Examples of water-resistant materials include plated steel sheets such as galvalume (aluminum-zinc alloy plated) steel sheets and galvanized steel sheets, as well as stainless steel sheets. The surfaces of the surface material 12 and back material 13 may be surface-treated as needed. Examples of surface treatments include painting with various resins, antifouling coatings, and other painting treatments.

[0095] The thickness of the surface material 12 and the back material 13 is, for example, 0.1 to 1 mm, but may also be 0.2 to 0.8 mm, or even 0.3 to 0.7 mm.

[0096] The surface layer only needs to be located on at least one surface of the composite board, typically the main surface. In the examples in Figures 2A and 2B, it is located on both main surfaces of composite board 1. Furthermore, the surface layer is not limited to the above examples and may be, for example, a coating.

[0097] The surface material 12 and / or back material 13 and the composite board 1 may be bonded together. Various adhesives such as rubber-based adhesives, urethane-based adhesives, and acrylic-based adhesives can be used for bonding.

[0098] Examples of the first fillers 15A and 15B are gypsum board, fiber-reinforced calcium silicate board, wood wool cement board, and wood cement board. Examples of the second filler 16 are ceramic fiber, alkali earth silicate wool (biosoluble fiber), alumina fiber, and rock wool felt. Examples of the sealant 17 are various types of rubber and elastomers.

[0099] The composite panel 11 may have the same thermal conductivity in the thickness direction as the composite board 1. The composite panel 11 may be an insulating panel.

[0100] The composite panel 11 may have performance equivalent to that of a fire-resistant structure under the Building Standards Act. For example, when the composite panel 11 has a thickness of 30 mm, it may have the heat-shielding and / or flame-retardant properties described above when heated for 30 minutes on one main surface based on the standard heating curve specified in ISO 834, and left for 1 hour and 30 minutes after heating.

[0101] The shape of the composite panel 11, when viewed perpendicular to its main surface, is typically square or rectangular. However, the shape is not limited to the above examples.

[0102] The thickness of the composite panel 11 is, for example, 10 mm or more, and may be 20 mm or more, 30 mm or more, 40 mm or more, or even 50 mm or more. The upper limit of the thickness is, for example, 300 mm or less, and may be 250 mm or less, 200 mm or less, 150 mm or less, 130 mm or less, 110 mm or less, or even 100 mm or less.

[0103] The area of ​​the composite panel 11 is 0.1 m². 2 More than 0.5m 2 Above 1m 2 More than 5m 2 More than 10m 2 More than 20m 2 Over 25m 2 In addition to the above, 50m 2 It may be greater than or equal to this. There is no upper limit on the area, but for example, 80m 2 The following applies: The longest side of the composite panel 11 may be 0.1m or more, 0.5m or more, 1m or more, 2m or more, 3m or more, 4m or more, 5m or more, or even 8m or more. There is no upper limit to the longest side, but for example, it should be 12m or less.

[0104] The composite panel 11 may have a configuration similar to that of a known sandwich panel, as long as it includes a composite board 1 as a core material.

[0105] An example of the application of the composite panel 11 is as a wall material for buildings. In other words, the composite panel 11 may be used as a wall material for buildings. The wall material may be an exterior wall or an interior wall, but the composite panel 11, which has a composite board 1 that can have low thermal conductivity, is particularly suitable for application to exterior walls. However, the applications of the composite panel 11 are not limited to the above example.

[0106] [Manufacturing method for composite panels] In the manufacturing method of the composite panel of this embodiment, a surface layer is placed on at least one surface of the composite board 1 to form the composite panel 11. The composite panel 11 may be manufactured according to a known sandwich panel manufacturing method, except that the composite board 1 is used as the core material. [Examples]

[0107] The present invention will be described in more detail below with reference to examples. The present invention is not limited to the examples shown below.

[0108] [Preparation of the sol-type solution] Tetramethoxysilane (TMOS) was prepared as a precursor compound capable of forming Q units through a gelation process, methyltrimethoxysilane (MTMS) as a precursor compound capable of forming T units, and dimethyldimethoxylane (DMDMS) as a precursor compound capable of forming D units.

[0109] 70 mL of a 5 mM aqueous acetic acid solution, 30 g of powdered urea, and 6 g of the nonionic surfactant Pluronic F-127 (manufactured by Sigma-Aldrich) were mixed and stirred to obtain a homogeneous solution. Next, the precursor compounds (total 50 mL) were added in the ratios (by volume) shown in Table 1 below, and stirring was continued at room temperature for 30 minutes. Solved solutions A1 to A5 were prepared by solving the precursor compounds by stirring in the presence of an acid catalyst. Solved solution A6 was prepared in the same manner as above, except that aluminum hydroxide particles (manufactured by Almorix, B-303) were added as a filler approximately 30 minutes after adding the precursor compounds. The amount of aluminum hydroxide particles was 35 parts by weight per 100 parts by weight of the precursor compound. The average particle size of the aluminum hydroxide particles was 6.5 μm.

[0110] [Table 1]

[0111] [Formation of composite boards] A rectangular prism of glass wool board (100 mm long x 100 mm wide x 11 mm thick) was placed on a rectangular pad as the base material. Then, each prepared sol solution was poured over the base material so that it was completely covered with the sol solution, thus immersing the base material. During immersion, the pad was vibrated by hand to ensure that the sol solution penetrated thoroughly into the interior of the base material. The glass wool board had a density of 96 kg / m³. 3This material (hereinafter referred to as Glass Wool I; manufactured by Mag Isover, Magboard), or a density of 16 kg / m³ 3 We used the following material (hereinafter referred to as Glass Wool II; manufactured by Asahi Fiber Glass, Acrylia).

[0112] Next, the entire mixture was heated to 60°C to generate ammonia from urea, and left for 5 hours to allow the polycondensation reaction and subsequent gelation to proceed, forming a wet gel. Subsequently, the wet gel was aged by standing at 60°C for 3 days. Next, solvent replacement with methanol, solvent replacement with isopropanol, and solvent replacement with heptane were carried out in sequence, and then the mixture was dried at atmospheric pressure and 120°C for 8 hours to form seven types of composite boards B1 to B7, which included the substrate and a low-density gel compounded with the substrate. For each solvent replacement, five times the volume of solvent relative to the volume of the substrate was used. Solvent replacement was carried out at room temperature. The shape and size of the formed composite boards were approximately the same as the shape and size of the substrate used. Table 2 below shows the combination of the sol-forming solution and the glass wool board for each composite board.

[0113] [Table 2]

[0114] The bending properties and thermal conductivity of the composite board fabricated as described above, as well as Aspen Aerogel's Pyrogel XT, glass wool board I alone, and glass wool board II alone as reference examples, were evaluated. The bending properties were evaluated by the three-point bending test described above, measuring the bending modulus, bending fracture strain, and bending strength. A Shimadzu Autograph was used for the three-point bending test. The shape of the test specimen was a rectangular parallelepiped with a length of 50 mm, a width of 10 mm, and a thickness of 5 mm. The direction of the load in the three-point bending test was perpendicular to the laminated surface of the fibers. Thermal conductivity was evaluated using the method described above. According to Aspen Aerogel's product description, Pyrogel XT is an aerogel bracket in which silica-based aerogel is impregnated into a nonwoven fabric of long glass fiber fibers.

[0115] The evaluation results are shown in Table 3 below. Figure 3 shows the stress-strain curve obtained from the three-point bending test. Note that the bending characteristics of Reference Example 3 could not be measured because the flexibility of Glass Wool Board II was so high that the test specimen could not be set in the measuring device.

[0116] [Table 3]

[0117] As shown in Table 3 and Figure 3, the composite boards of the examples exhibited an excellent balance of elastic modulus and fracture strain, making them suitable for use as wall materials. Furthermore, the composite boards of Examples 2 and 3 had a thermal conductivity of approximately 0.02 W / mK, demonstrating excellent heat insulation properties. It is estimated that, given the same substrate, the thermal conductivity of composite boards is primarily influenced by their pore structure rather than the composition of the low-density gel. Therefore, it is estimated that the thermal conductivity of other examples, formed under the same manufacturing conditions and with similar pore structures, would also be around 0.02 W / mK. On the other hand, the composite boards of the comparative examples lacked sufficient elastic modulus or fracture strain, making them unsuitable for wall materials. Additionally, while the composite boards of the examples possessed a sufficient flexural modulus for self-support, the composite board of Comparative Example 2 had a low flexural modulus and lacked self-support. Although the thermal conductivity of Pyrogel XT in Reference Example 1 was lower than that of the glass wool board in Reference Example 2, its elastic modulus was significantly lower, making it unsuitable for wall materials. The glass wool board in Reference Example 2 had suitable values ​​for wall material in terms of both elastic modulus and fracture strain, but its thermal conductivity was inferior.

[0118] [Other characteristics] (density) The densities of the composite boards in Examples 2 and 3 were 259 kg / m³, respectively. 3 and 269 kg / m 3 The density was evaluated using the method described above.

[0119] (Water absorption) The water absorption capacity of the composite boards in Examples 2 and 3 was 1.0 g / cm³, respectively. 3 and 0.5 g / cm³3 The water absorption capacity of Pyrogel XT in Reference Example 1 was 1.4 g / cm³. 2 The water absorption capacity of the glass wool board in Reference Example 2 is 36.7 g / cm³. 3 The amount of water absorbed was evaluated using the method described above.

[0120] (Fireproof performance) The composite board of Example 2, when 30 mm thick, exhibited flame-retardant properties when heated for 30 minutes on one main surface based on the standard heating curve specified in ISO 834, followed by 1 hour and 30 minutes of standing time after heating. Furthermore, the composite board of Example 5, which incorporated fillers, when 30 mm thick, exhibited both heat-shielding and flame-retardant properties when heated for 30 minutes on one main surface based on the standard heating curve specified in ISO 834, followed by 1 hour and 30 minutes of standing time after heating. [Industrial applicability]

[0121] The composite board and composite panel of the present invention are suitable for application as wall materials in buildings. [Explanation of symbols]

[0122] 1. Composite board 2 Base material 3. Low-density gel 11. Composite Panel 12. Surface material (which is the surface layer) 13. Backing material (which is the surface layer)

Claims

1. The material comprises a substrate and a low-density gel compounded with the substrate. Having a flexural modulus of 4.0 MPa or higher and a flexural fracture strain of 0.05 or higher, The low-density gel has a skeleton containing polyorganosiloxane chains, The aforementioned polyorganosiloxane chain has a T unit as its main constituent unit, A composite board in which the density of the aforementioned base material is 40 kg / m³ or more.

2. The composite board according to claim 1, wherein the composite board has a bending strength of 2.5 MPa or more.

3. The aforementioned substrate is a porous material, The composite board according to claim 1, wherein the low-density gel body is present inside the pores of the substrate.

4. The composite board according to claim 1, wherein the substrate comprises at least one selected from the group consisting of glass wool and rock wool.

5. The composite board according to claim 1, further comprising a filler.

6. The composite board according to claim 5, wherein the filler is at least one selected from the group consisting of metal hydroxide particles and metal oxide particles.

7. The composite board according to claim 1, for use as a wall material for buildings.

8. A composite board according to any one of claims 1 to 7, A surface layer disposed on at least one surface of the composite board, A composite panel equipped with these features.

9. The composite panel according to claim 8, for use as a wall material for buildings.

10. A method for manufacturing a composite board according to any one of claims 1 to 7, The process involves immersing the substrate in a solution containing a sol of a precursor compound having a hydrolyzable functional group, and allowing the sol to gel while the gelation process is carried out to form a wet gel. The wet gel is dried to form the composite board containing the substrate and the low-density gel body compounded with the substrate, A method for manufacturing a composite board, including [the specified element].

11. The method for producing a composite board according to claim 10, wherein the precursor compound is a silicon compound.

12. A method for manufacturing a composite board according to claim 10, wherein the wet gel is dried by drying at atmospheric pressure.

13. A method for manufacturing a composite panel according to claim 8, A method for manufacturing a composite panel, comprising arranging a surface layer on at least one surface of the composite board.

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