JP2009143794A - Ceramic having low heat storability, and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the abnormal rise in the temperature of the surface of a ceramic, thus, particularly, in the case of a tile, to suppress the rise of the temperature in a room, and further, to suppress deterioration in an adhesive as a pasting agent and the peeling of the tile thereby. <P>SOLUTION: By using a ceramic whose surface is coated with a glaze including an inorganic pigment having infrared reflectivity, the glaze on the surface of the ceramic reflects infrared rays as the cause of the rise of the temperature in the ceramic, so as to suppress the rise of the temperature in the ceramic. Thus, the rise of the temperature in a room can be mitigated. Particularly, in the case of a tile, deterioration in an adhesive used for fixing the tile and the peeling of the tile thereby can be suppressed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a low-heat-storing ceramic that suppresses the temperature rise of ceramics caused by irradiation with infrared rays contained in direct sunlight and the like, and a method for manufacturing the same.

  Conventional tiles, especially tiles used outdoors such as roofs, outer walls, and outer floors, are warmed by direct sunlight, especially dark-colored porcelain tiles that easily absorb heat. May reach. And the heat is transmitted to the room of the building, and it is a hindrance to efficiently obtain the cooling effect in summer. In recent years, when a tile is attached to a frame, not only mortar but also an organic adhesive has been used. In construction using such an adhesive, if the temperature of the tile becomes high, deterioration of the adhesive is promoted, and in the worst case, there is a concern about a problem of tile peeling.

  Therefore, in order to compensate for this drawback, a ceramic tile in which a heat insulating layer made of foam glass is integrally formed on the back surface has been developed (Patent Document 1). However, according to this ceramic tile, although a heat insulating effect can be obtained, the tile surface itself becomes a high temperature due to direct sunlight or the like, so that it is not sufficient in terms of peeling due to deterioration of the adhesive and a heat insulating effect.

  Further, it is known that the temperature rise of tiles due to direct sunlight or the like is remarkable in dark and dark tiles that absorb infrared rays.

  Under such circumstances, there has been a need for ceramic tiles with low heat storage properties that have heat insulation and delamination suppression properties by suppressing the temperature rise of the tile itself. Moreover, the clay roof also has a problem due to the temperature rise, and there is a similar situation regarding the necessity of suppressing the temperature rise.

JP 2003-227221 A

  The present invention has been conceived under such circumstances, and an object of the present invention is to prevent the surface of the tile from becoming abnormally hot, thereby increasing the temperature in the building and attaching the tile. It is an object of the present invention to provide a ceramic tile having a low heat storage property, which suppresses deterioration of an adhesive as an agent and thereby peeling of the tile. Another problem is to provide a clay roof tile with low heat storage.

  In order to solve this problem, by using ceramics with glaze containing inorganic pigments with infrared reflectivity on the surface, glaze on the ceramic surface reflects the infrared rays that are the cause of temperature rise and suppresses temperature rise of the ceramics. . Thus, for example, in the case of tiles, even if dark tiles are used, the rise in the temperature in the building can be mitigated, and the deterioration of the adhesive used for fixing the tiles and the resulting peeling of the tiles can be prevented. It becomes possible to suppress.

That is, the present invention has the following configuration.
(1) A low heat storage ceramic material in which a glaze containing an inorganic pigment having infrared reflection characteristics is applied to the ceramic surface.
(2) The ceramic body according to (1), wherein the ceramic body is a lightweight ceramic body having a heat insulating property with a bulk specific gravity of 0.4 to 1.9 and a thermal conductivity of 0.2 to 0.9 W / m · K. Low heat storage ceramics.
(3) The low heat storage ceramics according to (1) or (2), wherein the ceramics are tiles or clay tiles.
(4) A method for producing a low-heat-storing ceramic, comprising applying a glaze containing an inorganic pigment having infrared reflection characteristics on a molded body using a ceramic raw material, followed by firing.

  According to the present invention, it is possible to suppress the temperature rise of the front and back surfaces of the ceramic itself, thereby, for example, in the case of a tile, alleviate the rise in the room temperature, and suppress the deterioration of the adhesive and the resulting peeling of the tile. It becomes.

  Hereinafter, the present invention will be described in detail.

  The low heat storage ceramics of the present invention suppress the temperature rise of the ceramic front and back surfaces caused by irradiation with infrared rays such as direct sunlight. For example, in the case of a tile, it is preferably about 1 to about 5 ° C., more preferably about about 5 ° C. as measured by the ASTM D4803 method, as compared to a black tile not treated with a glaze containing an inorganic pigment having infrared reflective properties. 5 to about 10 ° C., and most preferably about 10 to about 15 ° C., so that when the low heat storage tile is used as a building outer wall, floor, roofing material, etc., the interior of the building The temperature increase can be mitigated, and the deterioration of the tile adhesive and the resulting peeling of the tile can be suppressed.

  The low heat storage ceramics according to the present invention can be used in places exposed to sunlight, such as exterior wall tiles, outdoor floor tiles, and roofing materials.

  First, a low heat storage tile is manufactured by the following tile manufacturing method. For example, the low heat storage tile of the present invention has a glaze containing an inorganic pigment having infrared reflection characteristics on at least one side of the surface of the obtained molded body, by forming the tile raw material into a desired shape by pressure molding or extrusion molding. Is obtained by baking. More specifically, first, clay, feldspar, porcelain stone, aragonite, wax stone, talc and lime are used as raw materials, and water is added. To. The clay is molded into a molded body as a tile body using a pressure molding machine, and then a separately prepared glaze containing an inorganic pigment having infrared reflecting properties is applied, placed in a firing furnace, and fired to reduce the temperature. Produce thermal storage tiles. At this time, porcelain tiles with a water absorption of about 1% or less, plaster tiles with a water absorption of about 1 to 5%, water absorption of about 5% or more by mixing at a specific mixing rate and baking at a specific baking temperature Of ceramic tiles. The low heat storage tile of the present invention may be obtained as any of these three types of tiles.

Next, the low heat storage clay tile is manufactured by the following clay tile manufacturing method.
For example, the low heat storage clay roof tile of the present invention is an inorganic pigment having an infrared reflection characteristic on at least one side of the surface of the molded body obtained by kneading and extruding the roof tile material and then pressing and molding to a desired shape. It is obtained by applying a glaze containing More specifically, first, using clay for clay and chamotte as raw materials, water is added, kneaded and extracted with a vacuum kneader to form a plate, and the plate-like compact is further subjected to pressure molding as a tile. After molding into a molded body and drying, a glaze containing an inorganic pigment having infrared reflection characteristics prepared separately is applied, put into a firing furnace, and fired to produce a low heat storage clay roof tile. Moreover, as a method of obtaining a tiled molded article, there is a method of obtaining a dry powder by pressure molding in the same manner as a tile, and the method of obtaining a molded article is not specified.

  And from a viewpoint of having low heat storage property, in both cases of tiles and clay roof tiles, the effect can be further increased by using a lightweight ceramic body having heat insulating properties. Lightweight ceramic body with heat insulation can be manufactured as a ceramic, with a bulk specific gravity of 0.4 and a thermal conductivity of 0.2 W / m · K or higher, a bulk specific gravity of 1.9 and a thermal conductivity of 0 Any ceramic body in the range of 9 W / m · K may be used. However, more preferably, a ceramic having a bulk specific gravity of 0.8 to 1.7 and a thermal conductivity of 0.4 to 0.8 W / m · K, which can provide appropriate performance and heat insulation performance as a ceramic, is desirable. .

  The glaze material used for the glaze is not limited as long as it is generally known as a glaze used in ceramics. For example, alkaline glaze, alkali-lime glaze, lime Any of cocoon, feldspar cocoon, and borate cocoon may be used. The straw raw material may be a ginger using the raw material as it is, or may be a raw raw material using a frit obtained by once melting the raw material, and a material suitable for the desired property of the tile can be appropriately selected and used. In addition, the glaze may contain an inorganic pigment having infrared reflection characteristics in the above glaze raw material, and may contain a peptizer, a spreading agent or the like, if necessary. Thereby, you may improve glazing property.

The inorganic pigment having infrared reflection characteristics contained in the glaze preferably contains 0.5 to 70 g / m ^{2 with} respect to the area of the ceramic surface on which the glaze has been applied, more preferably 10 -60 g / m ² , more preferably 20-55 g / m ² , most preferably 20-50 g / m ² . If it is less than 0.5 g / m ² , the infrared reflection characteristics may be deteriorated, and if it exceeds 70 g / m ² , an increase in the infrared reflection effect cannot be expected.

  As described above, the glaze can be prepared by a conventional method and is not limited at all. For example, the glaze can be obtained as a mixture by adding water to a glaze raw material and an inorganic pigment and pulverizing them with a mill. In addition, the raw material and the inorganic pigment may be mixed in water while stirring at room temperature. If necessary, the raw material and the inorganic pigment are mixed with a peptizer, a spreading agent, and the like. Also good.

In the present invention, the inorganic pigment having infrared reflection characteristics is not particularly limited as long as it has a property of hardly absorbing infrared rays, and is an element selected from Fe, Cr, Mn, Cu, Co and Ni. Compounds containing are preferred. In particular, oxides and composite oxides of the above elements are preferable. Specific inorganic pigments having infrared reflection characteristics include FeO, FeO (OH), Fe ₂ O ₃ , CrO, Cr ₂ O ₃ , Cr ₂ O ₃ .2H ₂ O, MnO, Mn ₂ O ₃ and MnO _2. , CuO, Cu ₂ O, CoO, CoO.Al ₂ O ₃ , Fe (Fe, Cr) ₂ O ₄ , (Co, Fe) (Fe, Cr) ₂ O ₄ , Cu (Cr, Mn) ₂ O ₄ , (Cu, Fe, Mn) (Fe, Cr, Mn) ₂ O ₄ , (Fe, Zn) (Fe, Cr) ₂ O ₄ , (Fe, Zn) Fe ₂ O ₄ , CoAl ₂ O ₄ , Co (Al , Cr) ₂ O ₄ , Cr ₂ O ₃ : Fe ₂ O ₃ , (Ni, Co, Fe) (Fe, Cr) ₂ O _{4 and the} like. Among these, Cr ₂ O ₃ : Fe ₂ O ₃ , (Cu, Fe, Mn) (Fe, Cr, Mn) ₂ O ₄ , Fe (Fe, Cr) ₂ O ₄ , (Co, Fe) (Fe, Cr) ₂ O ₄ , Cu (Cr, Mn) ₂ O ₄ , (Ni, Co, Fe) (Fe, Cr) ₂ O ₄ are preferable. Moreover, the said oxide and composite oxide can be used individually or in combination of 2 or more types, and the low heat storage ceramics colored in the desired color can be manufactured.

When the ceramic is a tile, in order to make a tile product of dark or dark color such as black, dark blue, dark green, brown, blue, etc., the above-mentioned inorganic pigments and generally used ceramic pigments are used. The inorganic pigment is contained in an amount of 0.5 to 70 g / m ^{2 with} respect to the area of the tile surface on which the glaze has been applied in order to obtain the heat storage tile of the present invention. More preferably, 10 to 60 g / m ² , more preferably 20 to 55 g / m ² , most preferably 20 to 50 g / m ^2, and a predetermined amount of glaze is applied to the infrared It is necessary to exert a lowering effect. Further, dark or dark colors such as black, dark blue, dark green, brown, and blue may be obtained singly or in combination of plural kinds of pigments according to the target color.

  EXAMPLES Hereinafter, the present invention will be specifically described by way of examples and comparative examples. However, the present invention is not limited to these examples, and other embodiments falling within the spirit and scope of the invention defined by the claims are also included in the present invention. included.

Examples 1-6
<Tile preparation>
A normal method on a molded body prepared by adjusting a glaze having the following composition and molding a clay for porcelain tiles composed of feldspar, porcelain stone, clay and black pigment to a thickness of 9 mm after firing. That is, 200 g / m ² of glaze dry matter was applied by an air spray device, and then fired at 1250 ° C. to prepare a porcelain tile. At this time, the bulk density of the black porcelain substrate is 2.4, and the thermal conductivity is 1.3 W / m · K. As the porcelain material for porcelain, a general material for dredging made of feldspar, porcelain stone, barium, lime and kaolin was used. AG-235 (manufactured by Kawamura Chemical Co., Ltd.) made of a complex oxide of Mn, Fe and Cr is used as an infrared reflective pigment, and a complex oxide black pigment 8893 (Nakajima) of a general ceramic pigment for comparison. Sangyo Co., Ltd.) was used.

The surface temperature was measured by two methods.
<Measurement of surface temperature 1>
The tiles prepared as described above were irradiated with infrared light above the tile and from a distance of 39.5 cm, approximately at right angles to the tile surface, according to ASTM D4803-97 “Test Method for Predicting Temperature Rise of Polyvinyl Chloride Building Materials”. A 250 W infrared lamp was arranged so that the tile could be irradiated, and after the infrared rays were irradiated to the tile at room temperature, the rising temperature of the tile surface was determined from the difference between the temperature when the temperature was stabilized and the room temperature.

  As Reference Example 1, the temperature rise in a normal white ceramic tile (high infrared reflectance) is described.

As a result, as shown in FIG. 1 in which the temperature difference from the surface of a normal black tile (Comparative Example 1) is plotted, the surface temperature is higher in Example 4 containing 18.2 g / m ² of the infrared reflective pigment in the surface glaze. An excellent temperature lowering effect was observed, and these lowering effects became more pronounced at a content of 46.2 g / m ² , and a dose-dependent surface temperature lowering effect was observed by addition of an infrared reflective pigment to the glaze. Moreover, although it was a black tile in Examples 4-6, it was suppressed to the raise of the substantially same temperature as the white tile which has the high infrared reflectance shown in the reference example 1, and hardly absorbs heat.

<Surface temperature measurement 2>
The tile prepared as described above was provided with an 185 W infrared lamp so that infrared rays could be irradiated on the tile surface at a distance of approximately 12 cm above the tile and from the distance, and the temperature of the front and back surfaces of the ceramic tile 30 minutes after the start of irradiation. Was measured using an infrared radiation thermometer (manufactured by Custom Corp.).

a 比較例３に対する温度低下を示す。

a Shows the temperature drop relative to Comparative Example 3.

  As Reference Example 1, the temperature rise in a normal white ceramic tile (high infrared reflectance) is described.

Compared to the front and back surface temperatures of the normal black tile (Comparative Examples 2 and 3), Example 4 containing an infrared reflective pigment in the surface glaze of 18.2 g / m ² has an excellent temperature lowering effect for the front and back surface temperatures. These lowering effects became more pronounced at a content of 46.2 g / m ² , and a dose-dependent surface and back surface temperature lowering effect was observed by adding an infrared reflective pigment to the glaze. Moreover, although it was a black tile in Examples 4-6, it was suppressed to the raise of the substantially same temperature as the white tile which has the high infrared reflectance shown in the reference example 1, and hardly absorbs heat.

(Measurement of infrared reflectance)
Infrared reflectance was measured by FT-IR in Example 4 and Comparative Example 1 of the same black tile.
As shown in FIG. 2, Comparative Example 1 has a low reflectivity and absorbs infrared rays, but Example 4 reflects infrared rays by increasing the reflectivity at a wavelength of 800 nm or more, which is an infrared region. Therefore, the surface temperature is difficult to increase.

Example 7
In Example 4, instead of the black base material for earthenware, a heat insulating lightweight tile having a bulk specific gravity of 1.5 and a thermal conductivity of 0.6 W / m · K, in which silicon carbide is added as a foaming agent to feldspar, clay and earthenware A glaze was applied by the method of Example 4 and fired at 1250 ° C., except that the substrate was used as a molded body having a predetermined thickness of 9 mm after firing.
[Surface temperature measurement 1]
This porcelain tile was irradiated with infrared rays by a 250 W infrared lamp in the same manner as in Example 4, and the surface temperature rise from room temperature of the ceramic tile at the time of stabilization after irradiation was measured. Moreover, the temperature rise of the back surface at this time was also measured. Moreover, what was prepared by the same glaze and method as the comparative example 1 using the said heat insulation lightweight tile base as the comparative example 4 was measured similarly.

[Surface temperature measurement 2]
The porcelain tile described in Example 7 was irradiated with infrared rays using a 185 W infrared lamp in the same manner as in Example 4, and the temperatures of the front and back surfaces of the ceramic tile 30 minutes after the start of irradiation were measured. Moreover, what was prepared by the same glaze and method as the comparative example 3 using the said heat insulation lightweight tile base as the comparative example 5 was measured similarly.

  Thermal insulation lightweight tiles have a large difference between the surface temperature and the back surface temperature due to their heat insulation performance, but the tile back surface temperature can be lowered, but the heat conductivity is low, so heat is easily accumulated on the surface, compared with ordinary porcelain tiles. Surface temperature tends to be high. Therefore, by applying a glaze containing an infrared reflective pigment as shown in Example 7, the surface temperature can be lowered, and the disadvantage of this heat insulating lightweight tile can be compensated. That is, the effect of lowering the back surface temperature can be further increased by combining the effect of reducing the surface temperature by the infrared reflective glaze with the heat insulating effect of the heat insulating lightweight tile.

  According to the present invention, the surface of the ceramic is prevented from being heated to an abnormally high temperature, thereby, for example, in the case of a tile, an increase in the indoor temperature of the building is mitigated, and the adhesive as an adhesive is deteriorated and the tile is peeled thereby Can be suppressed.

FIG. 1 is a graph showing the surface temperature difference (according to ASTM D4803) between the infrared reflective pigment content of the example and Comparative Example 1. FIG. 2 is a graph showing the reflectance at each wavelength for the ceramic of the present invention (Example 4) and Comparative Example 1.

Claims (4)

Low heat storage ceramics with glaze containing inorganic pigments with infrared reflection properties on ceramics. 2. The low heat storage ceramic according to claim 1, wherein the ceramic base is a lightweight ceramic base having a thermal insulation with a bulk specific gravity of 0.4 to 1.9 and a thermal conductivity of 0.2 to 0.9 W / m · K. . 3. The low heat storage ceramics according to claim 1, wherein the ceramics are tiles or clay tiles. A method for producing a low-heat-storing ceramic, comprising applying a glaze containing an inorganic pigment having infrared reflection characteristics on a molded body using a ceramic raw material, followed by firing.

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