JP5854422B2 - Thermosensitive inorganic composition - Google Patents

Description

  The present invention relates to a temperature-sensitive inorganic composition, a coating material of the composition, and a temperature-sensitive article including a substrate having a layer of the composition.

  Conventionally, as a material having an effect of suppressing heat transfer to the non-temperature-raising side in an environment where continuous rapid heating is performed in the atmosphere as defined in JIS R 1311, porous materials (Patent Documents 1 to 4) and reflective films (Patent Documents 5 to 6) have been used. These materials can be classified as non-temperature-sensitive heat transfer suppression materials because the film thickness and shape of the material itself do not change greatly depending on the temperature. On the other hand, heat transfer suppression materials whose film thickness and shape change in response to rapid heating can be classified as temperature-sensitive heat transfer suppression materials.

  In a non-thermosensitive material porous body or reflective film, the film thickness is a major factor in determining the heat transfer suppression performance, and therefore has a large film thickness even in an environment where rapid heating is not performed. Accordingly, a product using a non-thermosensitive material has a larger volume corresponding to the film thickness, so that more space is required during manufacture and transportation.

  On the other hand, since the heat-sensitive material exhibits heat transfer suppression performance with respect to temperature, the film thickness can be made thinner than the non-temperature-sensitive material. Thereby, in the product using a temperature sensitive material, the cost at the time of manufacture and transportation can be reduced.

  In recent years, several examples in which a temperature-sensitive material using a sodium silicate aqueous solution is applied to a general construction member have been reported. Non-Patent Document 1 discloses Ministry of International Trade and Industry Notification No. 1125 regarding a laminate in which a water-containing gel (sodium silicate aqueous solution: JIS standard No. 3 sodium silicate aqueous solution) is filled on both sides of a liquid crystal light adjuster as a porous body heat transfer inhibiting substance. As a result of the test based on the above, it was described that the product had sufficient performance to pass the class B.

  In Patent Document 7, when a laminated formed body obtained by sandwiching a plate-shaped transparent formed body prepared from a mixed aqueous solution of a hydrophilic resin and a sodium silicate aqueous solution between glass plates was tested according to a temperature curve defined in JIS R 1311. In the rapid heating test for 60 minutes, the glass was not dropped off, and no harmful smoke or the like leaked to the rapid heating back surface.

  Patent Document 8 discloses an oil-in-water emulsion (emulsion) porous material heat transfer suppression material in an aqueous solution containing sodium silicate aqueous solution or water-based polymer as a disperse phase and an ultraviolet curable material as a dispersoid. The film was applied to a thickness of 3000 μm, the coating surface was treated with a gas burner for 5 minutes, and the growth height and shape of the porous body layer were evaluated. The porosity and interlayer adhesion during rapid heating were both good. It is stated that.

  The temperature-sensitive inorganic materials described in these documents can be said to be typical and useful in this technical field. However, since the organic substance is contained in the sodium silicate aqueous solution, the porous body formed by rapid heating is used. By exhibiting a color other than white, radiant heat is generated from the porous body itself derived from coloring, and the effect of suppressing heat transfer to the non-temperature-raising side may not be good. Moreover, the evaluation test may not satisfy the rapid heating temperature and time conditions defined in JIS R 1311. Further, since the porous heat transfer suppressing material is sandwiched between the plurality of plate-like substances, the thickness becomes large, which causes a problem in terms of space for manufacturing and transportation.

JP-A-9-105186 JP 7-82964 A JP-A-11-93289 JP 2007-320057 A JP-A-6-272060 JP 2003-313053 A JP-A-9-227179 JP-A-5-105827

Japanese Utility Model Publication No. 5-62537

  An object of the present invention is to provide a temperature-sensitive inorganic composition based on sodium silicate, in which a porous body is formed by heating, and the porosity is maintained or improved even under a high temperature by further heating. .

As a result of intensive studies to achieve the above object, the present inventors have obtained a temperature-sensitive inorganic material prepared by mixing a sodium silicate aqueous solution with aluminum silicate and a metal carbonate such as strontium carbonate. After the composition formed a porous body by heating, it was found that the porosity was maintained or improved even at a high temperature by further heating, and the present invention was completed. That is, the present invention includes the following inventions.
[1] Sodium silicate having a value obtained by dividing the number of moles of silicon dioxide by the number of moles of disodium monoxide from 2.0 to 3.8, and 100 parts by weight of solid content of silicon dioxide of the sodium silicate On the other hand, it contains 5 to 80 parts by weight of aluminum silicate, 0.5 to 300 parts by weight of metal carbonate, 0 to 10 parts by weight of metal hydroxide, and 0 to 150 parts by weight of silica gel. Inorganic composition.
[2] The composition according to [1], wherein the metal carbonate is at least one compound selected from the group consisting of alkali metal carbonate, magnesium carbonate, alkaline earth metal carbonate and zirconium carbonate.

[3] The composition according to [1] or [2], wherein the metal hydroxide is at least one compound selected from the group consisting of alkali metal hydroxides and alkaline earth metal hydroxides.
[4] The composition according to any one of [1] to [3], further including 0.3 to 900 parts by weight of an inorganic aggregate with respect to 100 parts by weight of solid content of silicon dioxide of sodium silicate.
[5] A sodium silicate aqueous solution having a value obtained by dividing the number of moles of silicon dioxide by the number of moles of disodium monoxide from 2.0 to 3.8, and a solid content of silicon dioxide of the sodium silicate aqueous solution of 100 weight 5 to 80 parts by weight of aluminum silicate, 0.5 to 300 parts by weight of metal carbonate, 0 to 10 parts by weight of metal hydroxide, and 0 to 150 parts by weight of silica gel. paint.
[6] A temperature-sensitive article comprising a substrate having a layer of the composition according to any one of [1] to [4].

  According to the present invention, there is provided a temperature-sensitive inorganic composition whose porosity is maintained or improved even after heating after becoming porous by heating.

In the thermosensitive inorganic composition of Example 1 and a comparative example, it is a figure which shows the change of the projection area of the porous body foamed by heating. In the thermosensitive inorganic composition of Examples 2-5 and a comparative example, it is a figure which shows the change of the relative area ratio which remove | divided the projection area of the porous body foamed by heating by the projection area at the time of the largest foaming.

  The temperature-sensitive inorganic composition of the present invention contains sodium silicate, aluminum silicate and metal carbonate, and optionally contains metal hydroxide and / or silica gel and / or inorganic aggregate. This temperature-sensitive inorganic composition is heated to form a porous body by foaming the composition (hereinafter, this phenomenon is also referred to as “initial foaming”), and then subjected to further heating at a high temperature (for example, 650 ° C.). Even in the above, the composition foams, and the porosity is maintained or improved (hereinafter, this phenomenon is also referred to as “late foaming”). Further, since the porous body formed by heating is almost white, it is considered that the radiant heat due to the color change is reduced and the heat transfer to the non-temperature rising side is suppressed. Furthermore, since the film thickness of the formed porous body layer is substantially uniform, the effect of suppressing heat transfer over the entire porous body can be expected. Moreover, since the temperature-sensitive inorganic composition of the present invention does not contain an organic compound (for example, vinyl chloride resin) that is harmful during thermal decomposition, it is a safe material that does not generate toxic smoke or gas due to rapid heating. I can say that. Furthermore, a temperature-sensitive inorganic composition can be easily prepared with an inexpensive material without using an expensive metal alkoxide. The temperature-sensitive inorganic composition of the present invention can be usually produced by mixing an aqueous sodium silicate solution with aluminum silicate, metal carbonate, and the like and drying the mixture. Although the moisture content of the composition after drying will not be limited if it is a range which does not impair the objective of this invention, it is 20 to 75% normally.

The term "sodium silicate" as used _{herein, Na 2 O · nSiO 2 ·} mH has 2 _O in the composition formula, the coefficient n, i.e. a value obtained by dividing the number of moles of silicon dioxide in moles monoxide disodium Represents a compound having an A of 2.0 to 3.8. Moisture is included in a range that does not impair the purpose of the temperature-sensitive inorganic composition of the present invention.

  Although it does not specifically limit as "metal carbonate", For example, Alkali metal carbonates, such as lithium carbonate, sodium carbonate, potassium carbonate; Magnesium carbonate; Alkaline earth metal carbonates, such as calcium carbonate, strontium carbonate, barium carbonate; Zirconium carbonate is mentioned.

  Sodium carbonate and potassium carbonate have a solubility of about 22 g and about 112 g in 100 ml of water at 20 ° C., respectively, and are easily dissolved in an aqueous sodium silicate solution. Therefore, the viscosity of the temperature-sensitive inorganic composition can be adjusted by adding these. Moreover, initial foamability is high compared with other metal carbonates.

  Magnesium carbonate has relatively high late foamability. This is probably because magnesium carbonate has low solubility in water, but even if the carbonic acid component is a solid, it is contained in the composition, thereby suppressing rapid generation and diffusion of carbonic acid during heating. Moreover, since the hardness increases when the temperature-sensitive inorganic composition containing magnesium carbonate is dried, it is advantageous in tightening screws that generate large frictional heat or in close contact with parts that are slidably heated.

  Calcium carbonate has low solubility in water, but has high initial foaming properties when compared with magnesium carbonate.

Zirconium carbonate has higher late foaming properties than other metal carbonates.
Strontium carbonate is preferable from the viewpoint of initial foamability and late foamability. In particular, since strontium carbonate has low solubility in water, it exhibits good late foamability.

  The addition amount of the metal carbonate is 0.5 to 300 parts by weight, preferably 0.9 to 200 parts by weight, particularly preferably 1.9 to 160 parts by weight based on 100 parts by weight of the solid content of silicon dioxide of the sodium silicate. Parts by weight. These metal carbonates can be used alone or in a mixture depending on the purpose and application.

  In the temperature-sensitive inorganic composition of the present invention, by adding aluminum silicate, it is possible to suppress a decrease in viscosity at a high temperature and maintain a porous body. The addition amount of aluminum silicate is 5 to 80 parts by weight, preferably 11 to 40 parts by weight with respect to 100 parts by weight of the solid content of silicon dioxide of the sodium silicate.

  The “metal hydroxide” is not particularly limited, and examples thereof include alkali metal hydroxides such as potassium hydroxide and sodium hydroxide; magnesium hydroxide; alkaline earth metal hydroxides such as calcium hydroxide. . These can be used alone or in a mixture depending on the purpose and application. In the temperature-sensitive inorganic composition of the present invention, it is preferable to add a metal hydroxide from the viewpoint of workability and transportability. By adding the metal hydroxide, the drying rate of the aqueous sodium silicate solution can be suppressed during the preparation of the temperature-sensitive inorganic composition. In addition, the hardness and flexibility of the temperature-sensitive inorganic composition can be adjusted. The addition amount of the metal hydroxide is 0 to 10 parts by weight, preferably 0 to 4.4 parts by weight with respect to 100 parts by weight of the solid content of silicon dioxide of sodium silicate.

  In the present specification, “containing 0 to X parts by weight” means that the target component may be included in the composition up to X parts by weight, and in the case of 0 part by weight, it may not be included. Therefore, for example, in the present specification, “containing 0 to 10 parts by weight of metal hydroxide” means that the composition of the present invention contains 100 parts by weight of solid metal of silicon dioxide in sodium silicate and 100% by weight of metal hydroxide. It means that 10 parts by weight or less of oxide may be included.

  In the temperature-sensitive inorganic composition of the present invention, the viscosity of the temperature-sensitive inorganic composition can be adjusted by adding silica gel, and the thixotropy can be improved. Furthermore, the late foamability tends to be improved by the addition of silica gel. In particular, addition of silica gel facilitates the preparation and processing of the temperature-sensitive inorganic composition, and can reduce wrinkles generated on the surface of the temperature-sensitive inorganic composition when it is dried. The amount of silica gel added is 0 to 150 parts by weight, preferably 8.5 to 90 parts by weight, based on 100 parts by weight of the solid content of sodium silicate silicon dioxide.

  The “inorganic aggregate” is not particularly limited as long as it is a material that supports the porous body formed by heating the thermosensitive inorganic composition of the present invention. For example, fiber such as glass wool and rock wool; And inorganic particles mainly composed of silicon dioxide such as sea sand. Washed and desalted sea sand can also be used. Preferably, glass wool that has been desolvated is used. These inorganic aggregates can be used alone or in a mixture depending on the purpose and application. In order to increase the strength (hardness) when drying the temperature-sensitive inorganic composition, inorganic particles of different sizes may be used. By adding an inorganic aggregate to the temperature-sensitive inorganic composition of the present invention, an effect of suppressing heat transfer to the non-temperature-raising side of the inorganic aggregate itself is expected. Moreover, wrinkles and cracks that occur when the temperature-sensitive inorganic composition is dried can be reduced. Furthermore, the volume change before and after drying is reduced, and the preparation and processing of the temperature-sensitive inorganic composition becomes easy. The added amount of the inorganic aggregate is 0.3 to 900 parts by weight with respect to 100 parts by weight of the solid content of silicon dioxide of sodium silicate.

  In addition to using the temperature-sensitive inorganic composition of the present invention alone, a paint can be prepared using the composition. In that case, water can be added as a known additive or solvent as long as the object of the present invention is not impaired. As additives, for example, pigments, desiccants, fluidity modifiers, ultraviolet absorbers, sagging inhibitors, heat resistance improvers, and the like can be used.

  One embodiment of the present invention is a temperature-sensitive article having a layer of the temperature-sensitive inorganic composition on a substrate. The base material is not particularly limited as long as it is used for existing building materials. For example, concrete, stone, crystallized glass, glass block, brick, glazed tile, glazed tile, lightweight cellular concrete board, asbestos Inorganic base materials such as cement calcium silicate board, precast reinforced concrete board, asbestos slate board, pulp cement board and gypsum board board; ceramics; synthetic resin; wood and the like. The method of forming the layer of the thermosensitive inorganic composition on the substrate includes a doctor blade method, a gel casting method, a casting method, a calendar method, and a spray coating method. It can be applied by a known method such as a roller coating method, a bar coating method, an air knife coating method, a brush coating method, or a dipping method, followed by drying. The thickness of the layer of the thermosensitive inorganic composition formed on the substrate is not limited as long as it does not impair the object of the present invention, but is usually 50 μm to several tens of mm.

  Hereinafter, the present invention will be described in detail with reference to examples. In the present invention, as long as it is the purpose of the present invention and does not particularly impair the effects of the present invention, modifications or partial changes and additions are optional and all fall within the scope of the present invention. .

The test method test was conducted by applying various temperature-sensitive inorganic compositions prepared on a slide glass and naturally drying, and then heating the temperature from room temperature to 800 ° C. at a rate of 20 ° C./min in an electric furnace in an air atmosphere. And kept at 800 ° C. for 2 hours. The bulkiness of the foam of the porous body was evaluated by the area obtained by the projection method for the change over time and the volume obtained by the Archimedes method for the quantitative change. That is, the area was evaluated by taking a photograph of the foamed thermosensitive inorganic composition for each arbitrary temperature, creating a projection image, and determining the area. At that time, the length was corrected based on the standardized carrier (25.86 mm) found in the photograph. On the other hand, regarding the volume of the porous body, the density of various temperature-sensitive inorganic compositions at 400 ° C., 600 ° C., and 800 ° C. was obtained by the Archimedes method, and the volume of the foamed bulk portion was converted to the volume. Furthermore, the sample was taken out from the electric furnace after the test, and the molten state was observed visually. In addition, about Examples 2-5, the area of arbitrary temperature was divided | segmented by the area which showed the maximum area in the test temperature range, and various temperature-sensitive inorganic compositions were evaluated by calculating | requiring a relative area ratio. The moisture content is determined by the weight difference (evaporation) before and after heating an arbitrary sample coated on a carrier with no change in weight at 600 ° C and heated at 600 ° C for 2 hours in an air atmosphere. ) Divided by the solid weight determined by the same heat treatment and multiplied by 100.

A sodium silicate aqueous solution is obtained by adding potassium hydroxide to a JIS standard No. 3 sodium silicate aqueous solution (SiO ₂ : 28 to 30%, Na ₂ O: 9 to 10%). Prepared to 11.7% disodium oxide and 1.7% dipotassium monoxide. Aluminum silicate, sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate, strontium carbonate, zirconium carbonate, silica gel, sea sand, and glass wool were all purchased from Wako Pure Chemical Industries.

[Example 1]
Preparation Method of Temperature-Sensitive Inorganic Composition Containing Sodium Carbonate 4 parts by weight of potassium hydroxide, 30.5 parts by weight of aluminum silicate, 3 parts by weight of silicon dioxide in JIS standard 3 sodium silicate aqueous solution 1.04 g of a thermosensitive inorganic composition prepared by mixing 1 part by weight of sodium carbonate was applied to a glass slide and allowed to dry naturally. The water content at this time was 68%. Hereinafter, this temperature-sensitive inorganic composition is referred to as sample Na.

Preparation method of thermosensitive inorganic composition containing potassium carbonate 4 parts by weight of potassium hydroxide, 30.5 parts by weight of aluminum silicate, 100 parts by weight of silicon dioxide in JIS standard 3 sodium silicate aqueous solution, 6 1.06 g of a thermosensitive inorganic composition prepared by mixing 1 part by weight of potassium carbonate was applied to a glass slide and allowed to dry naturally. The water content at this time was 61%. Hereinafter, this temperature-sensitive inorganic composition is referred to as Sample K.

Preparation Method of Temperature-Sensitive Inorganic Composition Containing Calcium Carbonate 4 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate with respect to 100 parts by weight of silicon dioxide in JIS No. 3 sodium silicate aqueous solution, 22 1.02 g of a thermosensitive inorganic composition prepared by mixing 4 parts by weight of calcium carbonate was applied to a glass slide and allowed to dry naturally. The water content at this time was 71%. Hereinafter, this temperature-sensitive inorganic composition is referred to as sample Ca.

Preparation method of thermosensitive inorganic composition containing magnesium carbonate 4 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate, 100 parts by weight of silicon dioxide in JIS standard 3 sodium silicate aqueous solution, 21 1.18 g of a thermosensitive inorganic composition prepared by mixing 8 parts by weight of magnesium carbonate was applied to a slide glass and allowed to dry naturally. The water content at this time was 60%. Hereinafter, this temperature-sensitive inorganic composition is referred to as sample Mg.

Preparation Method of Temperature-Sensitive Inorganic Composition Containing Strontium Carbonate 4 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate, 85 parts per 100 parts by weight of silicon dioxide in JIS standard 3 sodium silicate aqueous solution 1.17 g of a thermosensitive inorganic composition prepared by mixing 6 parts by weight of strontium carbonate was applied to a slide glass and allowed to dry naturally. The water content at this time was 32%. Hereinafter, this temperature-sensitive inorganic composition is referred to as sample Sr.

Preparation Method of Temperature-Sensitive Inorganic Composition Containing Zirconium Carbonate 4 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate with respect to 100 parts by weight of silicon dioxide in JIS standard 3 sodium silicate aqueous solution, 65 1.21 g of a thermosensitive inorganic composition prepared by mixing 8 parts by weight of zirconium carbonate was applied to a slide glass and allowed to dry naturally. The water content at this time was 24%. Hereinafter, this temperature-sensitive inorganic composition is referred to as sample Zr.

Test results The test results are shown in FIG. The vertical axis | shaft of FIG. 1 represents the projection area of the porous body foamed at arbitrary temperature in various temperature-sensitive inorganic compositions. Table 1 is a table comparing the bulkiness of porous bodies formed by heating various temperature-sensitive inorganic compositions in Example 1 and Comparative Examples, using the volume determined by the Archimedes method. Moreover, the comparative example mentioned later is also written together in FIG.

  From the results, it is understood that the areas of samples Na, K, Ca, Mg, Sr and Zr all increased again around 650 ° C.

  Samples Na, K, and Ca showed a maximum area in a temperature region of 500 ° C. or lower and decreased when the temperature was 500 ° C. or higher, but re-foamed from around 700 ° C. to increase the area. When held at 800 ° C., samples Na and K were maintained for 10 minutes, and sample Ca was maintained for 2 hours without melting and deterioration.

  Sample Mg had a relatively small area at 600 ° C. or lower, but gradually increased at 600 ° C. or higher, and reached a maximum at 750 ° C. Although the area decreased at 800 ° C., the area was larger than the area at 600 ° C. or lower even when held for 2 hours. The sample taken out from the electric furnace after the test hardly remained melted and maintained a porous body and showed a good state.

  The sample Sr kept the area from around 350 ° C. up to 600 ° C. and became smaller at 650 ° C. When heating was continued, the area increased again from around 700 ° C., and reached a maximum at 750 ° C. Although the area was small at 800 ° C., the area was almost the same as that at 600 ° C. or lower even when held for 2 hours. The sample taken out from the electric furnace after the test hardly remained melted and maintained a porous body and showed a good state.

  Sample Zr had a relatively small area at 700 ° C. or lower. When the temperature became 700 ° C. or higher, the area gradually increased. When kept at 800 ° C. for 2 hours, the maximum area was obtained. The sample taken out from the electric furnace after the test hardly remained melted and maintained a porous body and showed a good state.

[Example 2]
Temperature sensitivity prepared with 6 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate and 85.6 parts by weight of strontium carbonate with respect to 100 parts by weight of silicon dioxide in JIS No. 3 sodium silicate aqueous solution. 1.17 g of the inorganic composition was applied to a slide glass and allowed to dry naturally. The water content at this time was 32%.

Aqueous solution of sodium silicate is JIS standard No. 3 sodium silicate aqueous solution _{(SiO 2: 28~30%, Na} 2 O: 9~10%) by adding potassium hydroxide to silicon dioxide 32.7%, carbon monoxide Prepared to 11.7% disodium and 1.7% dipotassium monoxide.

  The test results are shown in FIG. The vertical axis in FIG. 2 represents a relative area ratio obtained by dividing the projected area of the porous body foamed at an arbitrary temperature by the projected area when foamed to the maximum in the test temperature range. Table 2 is a table comparing the bulkiness of the porous bodies formed by heating various temperature-sensitive inorganic compositions in Examples 2 to 5 and Comparative Examples in terms of volumes determined by the Archimedes method.

  From the results, it is understood that the temperature-sensitive inorganic composition porousd at 350 ° C. or less at the start of the test kept the area ratio up to 600 ° C. and decreased at 650 ° C. When heating was continued, the area ratio increased again from around 700 ° C., and reached a maximum at 750 ° C. Although the area ratio decreased at 800 ° C., the area ratio similar to the area ratio at the start of the test was maintained even when held for 2 hours. The sample taken out from the electric furnace after the test hardly remained melted and maintained a porous body and showed a good state.

[Example 3]
4 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate, 92.8 parts by weight of strontium carbonate, 15.4 parts by weight with respect to 100 parts by weight of silicon dioxide in JIS No. 3 sodium silicate aqueous solution 1.19 g of the thermosensitive inorganic composition prepared with the silica gel was applied to a slide glass and allowed to air dry. The water content at this time was 37%.

A sodium silicate aqueous solution is obtained by adding potassium hydroxide to JIS standard No. 3 water sodium silicate aqueous solution (SiO ₂ : 28 to 30%, Na ₂ O: 9 to 10%). Prepared to 11.7% disodium oxide and 1.7% dipotassium monoxide.

  The test results are shown in FIG. From the results, it is understood that the temperature-sensitive inorganic composition porousd at 350 ° C. or less at the start of the test kept the area ratio up to 600 ° C. and decreased at 650 ° C. When heating was continued, the area ratio increased again from around 700 ° C., and reached a maximum at 750 ° C. Although the area ratio decreased at 800 ° C., the area ratio similar to the area ratio at the start of the test was maintained even when held for 2 hours. The sample taken out from the electric furnace after the test was hardly melted and deteriorated and maintained a porous body, and showed a good state even in a system to which silica gel was added.

[Example 4]
4 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate, 106.7 parts by weight of strontium carbonate, 15.3 parts by weight with respect to 100 parts by weight of silicon dioxide in JIS No. 3 sodium silicate aqueous solution 1.20 g of a temperature-sensitive inorganic composition prepared with 18.2 parts by weight of glass wool was applied to a slide glass and allowed to dry naturally. The water content at this time was 40%.

Aqueous solution of sodium silicate is JIS standard No. 3 sodium silicate aqueous solution _{(SiO 2: 28~30%, Na} 2 O: 9~10%) by adding potassium hydroxide to silicon dioxide 32.7%, carbon monoxide Prepared to 11.7% disodium and 1.7% dipotassium monoxide.

  The test results are shown in FIG. From the results, it is understood that the temperature-sensitive inorganic composition porousd at 350 ° C. or less at the start of the test maintained its area ratio up to 700 ° C. and re-foamed and reached a maximum at 750 ° C. Although the area ratio decreased at 800 ° C., an area ratio larger than the area ratio at the start of the test was exhibited even when held for 2 hours. The sample taken out from the electric furnace after the test hardly melted and deteriorated and maintained a porous body, and showed a good state even in a system to which silica gel and glass wool were added.

[Example 5]
4 parts by weight of potassium hydroxide, 35.6 parts by weight of aluminum silicate, 91.8 parts by weight of strontium carbonate, 15.9 parts by weight with respect to 100 parts by weight of silicon dioxide in JIS No. 3 sodium silicate aqueous solution 1.26 g of a thermosensitive inorganic composition prepared with 9.9 parts by weight of glass wool, 317.0 parts by weight of sea sand was applied to a slide glass and allowed to dry naturally. The water content at this time was 21%.

Aqueous solution of sodium silicate is JIS standard No. 3 sodium silicate aqueous solution _{(SiO 2: 28~30%, Na} 2 O: 9~10%) by adding potassium hydroxide to silicon dioxide 32.7%, carbon monoxide Prepared to 11.7% disodium and 1.7% dipotassium monoxide.

  The test results are shown in FIG. From the results, it is understood that the temperature-sensitive inorganic composition porousd at 350 ° C. or less at the start of the test maintained its area ratio up to 700 ° C. and re-foamed and reached a maximum at 750 ° C. Although the area ratio decreased at 800 ° C., an area ratio larger than the area ratio at the start of the test was exhibited even when held for 2 hours. The sample taken out from the electric furnace after the test was hardly melted and deteriorated and maintained a porous body, and showed a good state even in a system to which silica gel, glass wool and sea sand were added.

[Comparative example]
1.08 g of a composition prepared with 4 parts by weight of potassium hydroxide was applied to a slide glass with respect to 100 parts by weight of silicon dioxide in a JIS standard No. 3 sodium silicate aqueous solution and allowed to dry naturally. The water content at this time was 58%.

Aqueous solution of sodium silicate is JIS standard No. 3 sodium silicate aqueous solution _{(SiO 2: 28~30%, Na} 2 O: 9~10%) in that the addition of potassium hydroxide, 32.7% of silicon dioxide, sodium oxide 11.7% and potassium oxide 1.7%.

  The test results are shown in FIGS. 1 and 2 and Tables 1 and 2. From the results, it is understood that the composition that was made porous at 350 ° C. or less at the start of the test kept the area ratio up to 500 ° C., and the area ratio became smaller as the temperature exceeded 500 ° C. Even when kept at 800 ° C. for 10 minutes, the area ratio became very small, indicating that it was melted and deteriorated.

以上より、実施例２〜５における感温性無機組成物は、試験した温度範囲全域に亘って良好な多孔性を示すことが確認された。

From the above, it was confirmed that the temperature-sensitive inorganic compositions in Examples 2 to 5 exhibited good porosity over the entire temperature range tested.

Claims (7)

The value obtained by dividing the number of moles of silicon dioxide by the number of moles of disodium monoxide is 2.0 to 3.8 and 5 parts by weight relative to 100 parts by weight of the solid content of silicon dioxide in the sodium silicate. and aluminum silicate of 80 parts by weight, and the metal carbonate 0.5 to 300 parts by weight, seen containing a metal hydroxide of 0 parts by weight, and a silica gel 0 to 150 parts by weight, the water content A temperature-sensitive inorganic composition for use as a heat transfer suppressing material, which is 20 to 75% . Metal carbonate is at least one compound of magnesium carbonated, it is selected from the group consisting of alkaline earth metal carbonate and zirconium carbonate composition of claim 1. The composition of Claim 1 or 2 whose silica gel is 0-90 weight part with respect to 100 weight part of solid content of the silicon dioxide of the said sodium silicate. The composition according to any one of claims 1 to 3 , wherein the metal hydroxide is at least one compound selected from the group consisting of alkali metal hydroxides and alkaline earth metal hydroxides. The composition according to any one of claims 1 to 4 , further comprising 0.3 to 900 parts by weight of an inorganic aggregate with respect to 100 parts by weight of a solid content of silicon dioxide of sodium silicate. The temperature sensitive article containing the base material which has a 50 micrometers or more layer comprised from the composition of any one of Claims 1-5 . A paint for preparing a temperature-sensitive heat transfer-suppressing article, comprising the composition according to any one of claims 1 to 5 and a solvent.

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