JP2018203549A - Vacuum heat insulation member and manufacturing method therefor - Google Patents

Abstract

To provide a vacuum heat insulation member having high adiabaticity and capable of being airtightly sealed at low temperature.SOLUTION: For solving the above described problem, the heat insulation member has a first substrate, a second substrate opposingly arranged to the first substrate with a space, an encapsulation part arranged on circumference of an internal space formed between the first substrate and the second substrate, and a gas adsorbent arranged in the internal space, in which the internal space is at a vacuum state, the gas adsorbent contains cerium, the encapsulation part consists of an encapsulation material containing a lead-free low melting point glass, and the lead-free low melting point glass contains VOand TeO.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a vacuum heat insulating member and a manufacturing method thereof.

  In vacuum insulation members such as vacuum insulation double-glazed glass panels that are deployed on window glass for building materials, the space between the two substrates is in a vacuum state, and the two substrates are used to maintain the vacuum state for a long period of time. The periphery of is hermetically sealed. Thereby, high heat insulation is expressed and maintained. A sealing material containing low-melting glass is applied to the hermetic sealing of the peripheral edge.

In recent years, with the promotion of ZEH (Zero Energy House) and ZEB (Zero Energy Building), a window glass having significantly higher heat insulation than conventional multi-layer glass panels has been required. In the present double-glazed glass window, the heat insulation is high in the order of the vacuum layer, the argon layer, and the air layer inside the panel. These heat transmissivities are in the range of 3.0 to 1.4 W / m ² · K. The glazing ZEH and ZEB 0.7W / ^{m 2} · K or less, has been required following 0.4W / ^{m 2} · K in some countries and locations. In order to further reduce the heat transmissibility, it is essential to increase the vacuum inside the multilayer glass panel.

  In addition, from the viewpoint of preventing damage due to high vacuum, safety, crime prevention, etc., it is required to apply tempered glass which is subjected to air-cooling tempering treatment and the like, which is hard to break. The tempered glass is intended to increase the strength by forming a compression strengthened layer on the surface. The reinforcing layer gradually decreases by heating at a temperature of about 320 ° C. or higher, and disappears when heated to about 400 ° C. or higher. For this reason, when using tempered glass for panel glass, it is necessary to seal at less than 400 ° C, preferably less than 320 ° C.

  From the above, vacuum insulation members such as a vacuum insulation double-glazed glass panel are strongly required to have high insulation by high vacuum and low sealing temperature.

  In Patent Document 1, in order to adsorb unnecessary gas in the vacuum space, a first glass panel, a second glass panel arranged to face the first glass panel, a first glass panel, and a second glass panel are disclosed. Disclosed is a glass panel unit comprising: a seal that hermetically bonds a glass panel; a vacuum space surrounded by the first glass panel, the second glass panel, and the seal; and a gas adsorber disposed in the vacuum space. Has been. The gas adsorbent is formed from a base material formed of inorganic material fibers or a porous body, and a liquid containing a getter attached to the base material. As the getter, zeolite, Fe-V-Zr alloy, Ba-Al An alloy is disclosed.

International Publication No. 2016/051788

  The gas adsorbent disclosed in Patent Document 1 suppresses deterioration of the degree of vacuum due to gases such as nitrogen, oxygen, and hydrogen released from each material inside the panel after hermetic sealing. However, these gas adsorbents are insufficiently activated when the sealing temperature is low, and a problem that gas adsorbing performance cannot be sufficiently exhibited when sealing at low temperature is assumed.

  An object of the present invention is to provide a vacuum heat insulating member that has high heat insulating properties and can be hermetically sealed at a low temperature.

In order to solve the above problems, a heat insulating member according to the present invention includes a first substrate, a second substrate disposed opposite to the first substrate with a space therebetween, and the first substrate and the second substrate. A sealing portion provided at the periphery of the internal space formed between, and a gas adsorbent disposed in the internal space, the internal space is in a vacuum state, the gas adsorbent contains cerium, The sealing portion is made of a sealing material containing lead-free low-melting glass, and the lead-free low-melting glass contains V ₂ O ₅ and TeO ₂ .

  ADVANTAGE OF THE INVENTION According to this invention, it can provide the vacuum heat insulation member which has high heat insulation and can be airtightly sealed at low temperature.

It is a perspective view of the vacuum heat insulation member concerning one embodiment of the present invention. It is sectional drawing of the vacuum heat insulating member which concerns on FIG. It is a cross-sectional enlarged view of the sealing part vicinity of the vacuum heat insulating member which concerns on one Embodiment of this invention. It is a DTA curve of a general glass composition. It is a figure which shows the manufacturing process of the vacuum heat insulation member which concerns on Example 1. FIG. It is a figure which shows the manufacturing process of the vacuum heat insulation member which concerns on Example 1. FIG. It is the schematic which shows the evaluation method of heat insulation.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings, a vacuum heat insulating multilayer glass panel which is a typical example of a vacuum heat insulating member. However, the present invention is not limited to the embodiments taken up here, and can be appropriately combined and improved without departing from the scope of the invention.

The present inventors conducted various investigations and examinations on the types of gas released from each material in the multilayer glass panel and the amount of the gas released. As a result, it was found that the CO ₂ gas released from the sealing material when sealing the peripheral edge of the multi-layer glass panel was the largest, and this was the main cause of the high vacuum inside the panel. Further, although a large amount of moisture is released from each material including the sealing material, it has been found that the moisture can be almost removed at a low temperature before being hermetically sealed. That is, even when the sealing temperature is low, it has been found that if a gas adsorbent that can be activated against CO ₂ adsorption is installed, a high vacuum inside the multilayer glass panel can be achieved.

  FIG. 1 is a perspective view of a vacuum heat insulating member according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the vacuum heat insulating member of FIG. The vacuum heat insulating member includes a first substrate 1, a second substrate 2 disposed so as to face the first substrate 1 with a space therebetween, and a space between the first substrate 1 and the second substrate 2. The sealing part 4 provided in the periphery of the internal space 5 formed, and the gas adsorbent 7 arrange | positioned in the internal space 5 are provided. The internal space formed by the first substrate 1, the second substrate 2, and the sealing portion 4 is in a vacuum state. In this specification, the vacuum state refers to a state where the pressure is reduced from the atmospheric pressure. A plurality of spacers 3 are arranged in the internal space 5. Since the internal space of the vacuum heat insulating double-glazed glass panel is in a vacuum state, a pressure difference between the atmospheric pressure and the internal space is generated, but the internal space can be maintained by arranging a spacer.

By disposing the gas adsorbent in the internal space, the CO ₂ gas released from the sealing material can be adsorbed by the adsorbent. As a result, the degree of vacuum in the internal space can be improved, and the heat insulation of the multilayer glass panel can be improved.

<First substrate and second substrate>
For the first substrate and the second substrate of the vacuum heat insulating multilayer glass panel, float plate glass, mold plate glass, rubbing glass, tempered glass, netted plate glass, lined plate glass and the like can be used. These may be subjected to air cooling strengthening treatment or chemical strengthening treatment. The number of spacers can be reduced by using tempered glass that has been air-cooled or chemically strengthened. In the case of using a spacer made of a material having a high thermal conductivity, heat insulation is improved by reducing the number of spacers. Moreover, it is preferable that the kind of these glass is cheap soda-lime glass.

  In the vacuum heat insulating member of FIG. 2, the heat ray reflective film 6 is laminated on the surface 2 of the second substrate. As shown in FIG. 2, a plate glass having a heat ray reflective film laminated on its surface can be used.

<Spacer>
The spacer is used to maintain the space between the two glass substrates. The spacer is not particularly limited as long as the spacer has a lower hardness than the double-glazed plate glass and has a suitable compressive strength. For example, glass, metal, alloy, steel, ceramics, plastic, etc. can be used. From the viewpoint of heat insulation, it is preferable to use a material having low thermal conductivity.

  The spacer shape is not particularly limited. For example, a cylindrical, spherical, linear, or net-like spacer can be used.

  The size of the spacer can be selected according to the thickness of the space between the two glass substrates. For example, when the distance between two glass substrates is set to 200 μm, a spacer having a diameter of about 200 μm may be used as the spacer. The interval at which the spherical, linear, and reticulated spacers are arranged is 200 mm or less, preferably 100 mm or less, and 10 mm or more. The spacers can be arranged regularly or irregularly as long as the distance is within the above-mentioned range.

  In addition, in order to obtain a space portion having an appropriate thickness in a vacuum state, it is effective to introduce spherical beads having a uniform particle diameter in the spacer or the sealing portion.

<Sealing part>
The sealing portion is formed of a sealing material including low melting point glass.

  The sealing material may contain low thermal expansion filler particles or metal particles in addition to the low melting point glass. A paste-like material in which these materials and a solvent are mixed can be applied to the periphery of the first substrate or the second substrate with a dispenser or the like, dried and temporarily fired. Alternatively, the paste-like material may be applied to both sides of a ribbon-like foil, dried, and then temporarily fired, as a sealing material.

As the low melting point glass, lead-free low melting point glass containing oxide glass (V ₂ O ₅ ) and tellurium oxide (TeO ₂ ) can be used. This is because a glass containing vanadium oxide and tellurium oxide has a low softening point and can be hermetically sealed at a low temperature. In addition, since the lead-based low melting glass contains a lot of lead specified as a prohibited substance of the RoHS directive, it is not preferable to apply it to a vacuum heat insulating double-glazed glass panel or the like because of the environment. The lead-free low-melting glass preferably further contains silver oxide (Ag ₂ O). Lead-free glass containing silver oxide in addition to vanadium oxide and tellurium oxide has a lower softening point. Therefore, it can be hermetically sealed at a lower temperature. Lowering the sealing temperature has the advantage that it can be manufactured at low cost because it is possible to shorten the manufacturing tact and reduce the investment cost for introducing mass production equipment for a vacuum heat insulating double-glazed glass panel or the like that is difficult to rapidly heat and cool. There is also an advantage that tempered glass can be applied to the first substrate and the second substrate. In the present specification, the low melting point glass means a glass having a softening point of 400 ° C. or lower.

The total amount of V ₂ O ₅ and TeO _{2 in} the low-melting glass is preferably 50 mol% or more and 80 mol% or less. Further, when Ag ₂ O is contained, the total amount of V ₂ O ₅ , TeO ₂ and Ag ₂ O is preferably 70 mol% or more, and more preferably 80 mol% or more and 98 mol% or less. . The content of V ₂ O ₅ is preferably 15 mol% or more and 45 mol% or less, the content of TeO ₂ is preferably 15 mol% or more and 45 mol% or less, and the content of Ag ₂ O is 10 mol%. It is preferable that it is 50 mol% or less. Further, the content of TeO ₂ is from 1 to 2 times molar ratio to _V 2 _{O 5,} the content of Ag ₂ O is 2 times or less in molar ratio with respect to _V 2 _{O 5} It is preferable.

The low melting point glass may contain 30 mol% or less of any one or more of K ₂ O, BaO, WO ₃ , MoO ₃ and P ₂ O ₅ . Any one or more of K ₂ O, BaO, WO ₃ , MoO _3, and P ₂ O ₅ are preferably included at 20 mol% or less. The low melting point glass further includes Fe ₂ O ₃ , Al ₂ O ₃ , Ga ₂ O ₃ , In ₂ O ₃ , Y ₂ O ₃ , La ₂ O ₃ , CeO ₂ , Er ₂ O ₃ and Yb as additional components. Any one or more of ₂ O ₃ may be included. The content of these additional components is preferably 5 mol% or less, and preferably 0.1 or more and 3.0 mol% or less.

  The content of the lead-free low melting point glass in the sealing material is preferably 40% by volume or more. The low melting point glass does not need to be kept amorphous after sealing, and may be crystallized.

As the low thermal expansion filler, those having a negative thermal expansion coefficient are preferable. By including the low thermal expansion filler particles, a difference in thermal expansion between the first substrate, the sealing portion, and the second substrate can be reduced, and a sealing portion with higher bonding strength can be obtained. Low thermal expansion filler particles having a negative thermal expansion coefficient include zirconium phosphate tungstate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ), niobium oxide (Nb ₂ O ₅ ), β-eucryptite (LiAlSiO _4). ), Quartz glass (SiO ₂ ), and the like. Among these low thermal expansion fillers, zirconium tungstate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ) is preferable. This is because zirconium tungstate phosphate has good wettability with lead-free low-melting glass containing vanadium oxide and tellurium oxide. From the viewpoint of achieving both airtightness and bonding strength, the content of the low thermal expansion filler particles in the sealing material is preferably 10% by volume or more and 45% by volume or less.

  The metal particles are preferably a low melting point metal having a melting point of 300 ° C. or lower. As the low melting point metal, for example, tin or a tin-based alloy can be used. As the tin-based alloy, an alloy containing any of silver, copper, zinc, and antimony can be preferably used. From the viewpoint of heat insulation and bonding strength, the ratio of the metal particles in the sealing material is preferably 10% by volume or more and 70% by volume or less.

  FIG. 3 shows an enlarged cross-sectional view of a sealing portion of a vacuum heat insulating member using a paste containing at least a low melting glass, a low thermal expansion filler, and a metal material as a sealing material. When a paste containing a low melting point metal as a metal material is used as a sealing material, a sealing portion is formed including the glass phase 8 and the metal phases 9 formed at both ends of the glass phase. Since the metal phase is formed at both ends of the glass phase, the gas released from the glass phase can be blocked by the metal phase. As a result, the amount of gas released into the panel can be reduced and the degree of vacuum can be improved.

  As a sealing material, when using the material which apply | coated the paste containing a low melting glass on both surfaces of a ribbon-shaped foil, and used the temporary baking, metal foil can be used as a ribbon-shaped foil. By using a material in which a paste containing low-melting glass is applied on both sides of a ribbon-like foil as a sealing material, the amount of low-melting glass used for the sealing material can be reduced. As a result, the amount of gas released from the low melting glass can be reduced and the degree of vacuum can be improved.

  As the ribbon-like metal foil, for example, an iron-nickel alloy, an iron-nickel-chromium alloy, an aluminum metal, an aluminum alloy, and a clad material thereof can be used.

<Gas adsorbent>
The gas adsorbent is a compound containing cerium. Examples of the compound containing cerium include cerium oxides such as CeO ₂ and Ce ₂ O ₃ and cerium carbonates such as cerium carbonate and cerium oxycarbonate.

The gas adsorbent disposed in the internal space of the vacuum heat insulating member needs to adsorb low-pressure CO ₂ . Since cerium-containing compounds can adsorb low-pressure CO ₂ compared to other gas adsorbents such as zeolite, they are arranged in the internal space of the vacuum heat insulating member and effective for adsorbing the gas released from the sealing material. It is. Moreover, since the compound containing cerium has a low activation temperature, it can be activated sufficiently at the sealing temperature when sealing the vacuum heat insulating member. This is particularly effective when the sealing temperature is low.

Further, the compound containing cerium includes at least one rare earth (lanthanide) selected from Sc, Y, La, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. It is preferable that an element is included. By adding these rare earth (lanthanide) elements, CO ₂ adsorption can be activated by heat treatment at a lower temperature. Among these rare earth elements, it is more preferable to add any one of La, Pr, Nd, Sm, and Gd.

  The compounding ratio of the rare earth element to cerium is preferably 0.001 or more and 1 or less, and more preferably 0.1 or more and 0.5 or less in terms of molar ratio. If the blending ratio of the rare earth elements is 0.5 or less, the structure of the composite material is a cerium oxide structure (fluorite structure), and the specific surface area is easily maintained.

The specific surface area of the adsorbent is preferably 30 m ² / g or more, more preferably 100 m ² / g or more, and still more preferably 200 m ² / g or more because it relates to the reaction rate and capacity of gas adsorption. Voids, to promote diffusion into the pores of the gas, and reducing the effective thermal conductivity of the adsorbent, is preferably 0.01 cm 3 / ^g or more, more preferably 0.05 cm ³ / G or more. In order to improve the transparency of the adsorbent, colloidal crystallization may be performed by using colloidal particles having a crystallite diameter of 10 nm or less and gently solidifying them.

  The gas adsorbent is preferably 0.01 or more and more preferably 0.1 or more and 1.0 or less in terms of weight ratio with respect to the low melting point glass contained in the sealing material. By setting the amount of the adsorbent to 0.01 or more, the gas generated from the low-melting glass can be adsorbed and the heat insulation can be improved. By setting the amount of the adsorbent to 1.0 or less, it is possible to suppress a decrease in heat insulation due to heat transfer by the adsorbent.

  The gas adsorbent may be disposed anywhere within the internal space of the vacuum heat insulating member. A space for arranging the gas adsorbent may be provided in the spacer, and the gas adsorbent may be arranged in the space. From the viewpoint of adsorbing desorbed gas from the sealing material, the vicinity of the installation position of the sealing material is preferable. Furthermore, it is more preferable to install an adsorbent at a position hidden from the naked eye with a sash from the viewpoint of the scenery of the glass. Further, since the adsorbent has a characteristic of releasing the adsorbed gas when heated, the degree of vacuum and the heat insulation may be lowered when the adsorbent temperature is increased. Therefore, it is preferable to install in a place where the temperature is low inside the multilayer glass. For example, in areas where the outdoor temperature is lower than the indoor temperature, such as in cold areas, the adsorbent is applied to the glass on the outdoor side of the double-glazed glass, and the outdoor temperature is higher than the indoor temperature, such as in warm areas. Then, an adsorbent may be applied and installed on the indoor glass. Depending on the season, the orientation of the double-glazed glass may be changed when the indoor and outdoor temperature levels are reversed.

  In the case of using a powdered gas adsorbent, the gas adsorbent can be placed in the internal space of the vacuum heat insulating member by applying a gas adsorbent and a solvent on the substrate. As a solvent for applying the adsorbent to the substrate, water, ethanol, BCA (butyl carbitol acetate), or the like can be used. Among these, it is preferable to use ethanol because it is easily volatilized and affects the surface structure of the adsorbent.

  The gas adsorbent needs to be activated before use. Examples of the activation method include chemical heat treatment and vacuum deaeration treatment. Although only one of these processes may be performed, a higher effect is expected by performing both. Although there is no restriction | limiting of the heat processing temperature, Especially 100 degreeC or more, More preferably, it is 200 degreeC or more, More preferably, it is 300 degreeC or more and 500 degrees C or less. Further, the vacuum degassing treatment is preferably 1 kPa or less, more preferably 1 Pa or less.

  When the vacuum heat insulating member is produced by sealing at 100 ° C. or higher and 500 ° C. or lower, the vacuum adsorbing step and the sealing step after disposing the gas adsorbent before activation in the internal space of the vacuum heat insulating member It can also serve as an activation process. A reduction in manufacturing cost is expected because the evacuation process or the sealing process also serves as an activation process.

In addition, after arrange | positioning the gas adsorbent after an activation process in the internal space of a vacuum heat insulation member, you may seal a vacuum heat insulation member. However, if the gas adsorbent after the activation treatment is taken out into the atmosphere, the CO ₂ in the atmosphere is absorbed before the CO ₂ in the internal space is absorbed, and therefore work in a vacuum atmosphere is required.

<Method for producing vacuum heat insulating member>
A vacuum heat insulating member according to an embodiment of the present invention seals the first substrate and the peripheral portion of the second substrate that are arranged to face each other with a predetermined interval with a sealing material, It can be manufactured by forming a sealable internal space between the second substrates and exhausting the internal space to a vacuum state. Specifically, the step of disposing the sealing material and the gas adsorbent on the first substrate, the stacking step of stacking and fixing the first substrate and the second substrate, the first substrate and the second substrate A sealing step of sealing with a sealing material, and a vacuum exhausting step of exhausting the internal space of the first substrate and the second substrate.

  When a paste-like sealing material is used, the sealing material is disposed on the first substrate by applying the sealing material to the first substrate and then pre-baking. In the case where a ribbon-shaped sealing material is used, the sealing material may be disposed on the first substrate.

  The gas adsorbent may be applied to the first substrate using any one of water, ethanol, and butyl carbitol acetate. Among these, it is preferable to use ethanol because it is easily volatilized and affects the surface structure of the adsorbent.

  In the stacking step, the first substrate and the second substrate may be stacked and then fixed with a plurality of clips or the like. In consideration of the heat resistance of the spring, the clip is preferably made of stainless steel or inconel. For the second substrate, a surface laminated with a heat ray reflective film may be used.

When either the first substrate or the second substrate has an exhaust port, a vacuum exhaust process is performed after the sealing process. In the sealing process, the laminated and fixed pair of substrates are hermetically sealed by heating to a temperature near or above the softening point of the sealing material, and then the internal space is exhausted from the exhaust port by a vacuum pump or the like in the vacuum exhaust process. Evacuate. An exhaust pipe is connected to the exhaust port, and after exhausting through the exhaust pipe, the inside of the internal space can be maintained in a vacuum state by sealing the exhaust pipe. The sealing temperature is preferably the temperature between the vicinity of the softening point T _{s of the} glass contained in the sealing material and the working point T _w .

Here, the characteristic temperature of the low-melting glass will be described. FIG. 4 shows an example of a differential thermal analysis (DTA) graph of the glass composition. In general, DTA of glass uses glass particles having a particle size of several tens of μm, and further uses high-purity alumina (α-Al ₂ O ₃ ) particles as a standard sample. Measured at temperature rate. As shown in FIG. 4, the starting temperature of the first endothermic peak, or the temperature at which the glass transitions from the supercooled liquid, is the transition point T _g , the endothermic peak temperature, or the point where the expansion of the glass stops is the yield point M. _g, the second endothermic peak temperature, or softened start temperature softening point T _s, Shoyuiten the temperature at which the glass is sintered T _sint, temperature pour point T _f of the glass begins to _melt, forming molten glass The temperature suitable for is called the working point T _w , and the starting temperature of the exothermic peak due to crystallization is called the crystallization starting temperature T _cry . In addition, each characteristic temperature is calculated | required by the tangent method.

In addition, characteristic temperatures such as T _g , M _g and T _s are defined by the viscosity of the glass, T _g is 10 ^13.3 poise, M _g is 10 ^11.0 poise, T _s is 10 ^7.65 poise, T _sint is ¹⁰ 6 poise, _{T f} is ¹⁰ 5 poise, _{T w} is the temperature corresponding to ¹⁰ 4 poise.

  When neither the first substrate nor the second substrate has an exhaust port, the sealing process and the vacuum exhaust process are performed simultaneously. Before the stacking step, a column member having a height higher than that of the sealing portion may be installed on the first substrate. The column member is made of a metal or an alloy, and the melting point thereof is preferably the pour point of the low melting point glass contained in the sealing material + 20 ° C. or less, and more preferably 320 ° C. or less. Specifically, Bi, Sn, gold-tin alloy, zinc-tin alloy, tin-silver eutectic solder can be used as the metal or alloy constituting the column member. A pair of substrates fixed by a laminating process is placed in a vacuum apparatus, and the substrate is evacuated while being heated to a temperature that is higher than the softening point of the low melting point glass and 20 ° C. higher than the pour point of the glass composition. In the present specification, the temperature near the softening point is defined as the temperature at the softening point ± 10 ° C, and the temperature near the pour point is defined as the temperature at the pour point ± 10 ° C. In the temperature process, the temperature is raised to the first temperature which is not less than the softening point of the low-melting glass and less than the melting point of the column member, and after holding at the first temperature, the pour point of the glass composition above the melting point of the column member +10 It is preferable that the temperature is raised to a second temperature which is a temperature equal to or lower than 0 ° C. and maintained at the second temperature. By setting it as the temperature profile as mentioned above, a sealing material and a column member are crushed simultaneously, and a favorable sealing state can be obtained. According to the above method, the process of providing an exhaust port on the substrate and the process of closing the exhaust port after evacuation can be reduced, and the manufacturing process can be simplified.

(Preparation of vacuum insulation glass panel)
Multi-layer glass was prepared using two rectangular parallelepiped soda-lime glasses (width 100 mm × depth 100 mm × height 3 mm) as the first substrate and the second substrate, respectively. FIG. 5 shows a manufacturing process of the vacuum heat insulating member according to the first embodiment. First, as shown in FIG. 5A, the sealing material 4 was applied onto the first substrate 1 using a dispenser so that the outer periphery was a square of 90 mm × 90 mm. Table 1 shows the structure of the sealing material. Characteristic temperature of the low melting point glass transition point _{T g} is 203 ° C. included in the sealing material used, sag _{M g} is 221 ° C., a softening point _{T s} is 258 ° C., Shoyuiten _{T sint} is 267 ° C., a pour point T _f was 282 ° C., working point T _w was 288 ° C., and crystallization start temperature T _cry was 349 ° C. The sealing material was prepared by mixing glass, filler material, and tin alloy at a volume ratio of 30:20:50. After the sealing material 4 was applied, it was calcined at 260 ° C. in the atmosphere. As shown in FIG. 5B, a high specific surface area CeO ₂ (made by Nikki) was applied as a gas adsorbent 7 inside the temporarily fired sealing material 4 in a mixed state with water. Thereafter, a metal Bi spacer 10 (height: 0.7 to 1 mm) was installed near the apex of the Ti wire type spacer 3 (φ200 μm) and the sealing material 4. As shown in FIG. 5C, the second substrate 2 is placed on top of the first substrate 1 to form a facing structure. Four sides of the first substrate 1 and the second substrate 2 were fixed using the clip 11.

The sample having the facing structure was evacuated with a vacuum pump in a vacuum heating furnace, so that the degree of vacuum was 2 × 10 ⁻² Pa. FIG. 6 shows an evacuation process according to the first embodiment. The first substrate 1 and the second substrate 2 fixed by the clip 11 in the stacked state were carried into the vacuum heating furnace 12 and evacuated by the vacuum pump 13. While evacuating, the heating furnace was heated to 280 ° C. at a heating rate of 6 ° C./min. The low-melting glass in the sealing material softened and flowed during the temperature rising process, and preparations for hermetic sealing were made. First, the sealing material softened, and then the metal Bi spacer disposed near the top melted. At this time, the first substrate 1 and the second substrate 2 are pressed against each other by the force and dead weight from the clip, but the distance between the first substrate 1 and the second substrate 2 is 200 μm by the Ti wire spacer 8. Kept in. Then, the sealing material hardened | cured by cooling a sample, and the vacuum heat insulation glass panel which maintained the space | gap of the 1st board | substrate 1 and the 2nd board | substrate 2 was able to be produced.

(Comparative Example 1)
A vacuum heat insulating glass panel was produced in the same manner as in Example 1 except that the gas adsorbent 7 was not applied to the inside of the temporarily fired sealing material 4.

  A vacuum heat insulating glass panel was produced in the same manner as in Example 1 except that ethanol was used instead of water when applying the gas adsorbent.

  A vacuum heat insulating glass panel was prepared in Example 1 except that BCA (butyl carbitol acetate) was used instead of water when applying the gas adsorbent.

(Comparative Example 2)
A glass panel was produced in the same manner as in Example 2 except that zeolite 13X was used instead of CeO ₂ as the gas adsorbent.

(Comparative Example 3)
A glass panel was produced in the same manner as in Example 2 except that zeolite 5A was used instead of CeO ₂ as the gas adsorbent.

A glass panel was produced in the same manner as in Example 2 except that Ce—Nd oxide was used instead of CeO ₂ as the gas adsorbent. The Ce—Nd oxide was produced by the following method.

60 g of urea, 16.45 g of ammonium cerium (IV) nitrate, and 2.63 g of Nd nitrate hexahydrate were dissolved in 300 ml of purified water. Thereafter, this solution was heated to 95 ° C. using a water bath with stirring, whereby the dissolved urea was decomposed into NH ₃ and CO ₂ by hydrolysis, and the pH was raised to generate a precipitate. Thereafter, the cake obtained by filtration and washing with 500 ml of purified water was collected and dried in air at 120 ° C. Thereafter, it was fired at 300 ° C. for 1 hour in air to obtain a sample powder (Ce—Nd oxide).

(Evaluation of thermal insulation performance)
About the vacuum heat insulation glass panel of Examples 1-4 and Comparative Examples 1-3, the heat insulation performance was evaluated with the following method. The schematic which shows the measuring method of the heat insulation performance based on an Example in FIG. 7 is shown. A cylindrical heater 14 heated and held at 60 ° C. is brought into contact with the center of the surface of the second substrate 2, and a thermometer 15 is brought into contact with the center of the surface of the first substrate 1 on the opposite side. The temperature change for 10 minutes was measured by the thermometer 15. It was determined that the lower the temperature rise, the higher the degree of vacuum in the internal space 5 and the higher the heat insulation. Table 2 shows the evaluation results of the heat insulation performance.

From Examples 1 to 4 and Comparative Example 1, it was found that the heat insulating property was improved by arranging the gas adsorbent inside the glass panel. In addition, from Examples 2 and 4 and Comparative Examples 2 and 3, the heat insulation performance varies depending on the type of adsorbent disposed inside the panel, and CeO ₂ and Ce—Nd oxide are more effective in improving the heat insulation than zeolite. I found out. In Example 4, since the temperature change was particularly small, it was found that the heat insulating property was improved by adding a rare earth / lanthanide element to CeO ₂ .

  From Examples 1 to 3, it was found that the heat insulating performance varies depending on the type of liquid used for applying the gas adsorbent. It has been found that ethanol is effective for applying the gas adsorbent.

DESCRIPTION OF SYMBOLS 1 ... 1st board | substrate, 2 ... 2nd board | substrate, 3 ... Spacer, 4 ... Sealing material (sealing part), 5 ... Internal space, 6 ... Heat ray reflective film, 7 ... Gas adsorption material, 8 ... Glass phase , 9 ... Metal phase, 10 ... Metal spacer, 11 ... Clip, 12 ... Vacuum furnace, 13 ... Vacuum pump

Claims (10)

A first substrate;
A second substrate disposed opposite to the first substrate across a space;
A sealing portion provided at a peripheral edge of an internal space formed between the first substrate and the second substrate;
A gas adsorbent disposed in the internal space,
The internal space is in a vacuum state,
The gas adsorbent is a compound containing cerium,
The sealing portion is made of a sealing material containing lead-free low-melting glass,
The lead-free low-melting-point _glass, vacuum insulation member, characterized in that it comprises a V 2 _{O 5} and TeO _2. The vacuum heat insulating member according to claim 1,
The vacuum heat insulating member, wherein the gas adsorbing material is carbonate or oxide. The vacuum heat insulating member according to claim 2,
The gas adsorbent contains at least one element selected from Sc, Y, La, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Vacuum insulation member. It is a vacuum heat insulation member as described in any one of Claims 1 thru | or 3, Comprising:
The vacuum heat insulating member, wherein the gas adsorbent has a specific surface area of 30 m ² / g or more. The vacuum heat insulating member according to any one of claims 1 to 4,
The lead-free low-melting glass further contains Ag ₂ O, and the vacuum heat insulating member. A vacuum heat insulating member according to any one of claims 1 to 5,
The vacuum heat insulating member, wherein the sealing portion further includes low thermal expansion filler particles. The vacuum heat insulating member according to claim 6,
The vacuum heat insulating member, wherein the low thermal expansion filler particles are any one of zirconium tungstate phosphate, niobium oxide, β-eucryptite, and quartz glass. It is a vacuum heat insulation member as described in any one of Claims 1 thru | or 7, Comprising:
The sealing material includes metal particles,
The vacuum heat insulating member, wherein the metal particles are tin or a tin-based alloy containing at least one of silver, copper, zinc, and antimony. A vacuum heat insulating member according to any one of claims 1 to 8,
The first substrate and the second substrate are plate glasses,
The vacuum heat insulating member is a double layer glass. The periphery of the first substrate and the second substrate arranged to face each other at a predetermined interval is sealed with a sealing material, and the inside which can be sealed between the first substrate and the second substrate A method of manufacturing a vacuum heat insulating member that forms a space and evacuates the interior space to form a vacuum state,
Applying a gas adsorbent to the first substrate or the second substrate using a solvent of water, ethanol, or butyl carbitol acetate,
The method for producing a vacuum heat insulating member, wherein the gas adsorbent is a compound containing cerium.

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