JPS5813667A - Coating agent for clay roof tile - Google Patents

Abstract

PURPOSE:The titled coating agent, capable of imparting the water absorption resistance and water permeation resistance to the clay roof tile ground before the calcination by application thereto, and consisting of specific inorganic oxides. CONSTITUTION:A coating agent containing (A) 2-10wt% one or more Na2O, K2O and Li2O, (B) 0-8wt% one or more CaO, MgO, BaO, ZnO and SrO, (C) 5-15wt% Al2O3, (D) 5-20wt% B2O3 and (E) 50-78wt% SiO2 or 2-7wt% component (A), 2-30wt% total amount of component (B) and PbO, 2-10wt% component (C), 5-15wt% component (D) and 50-78wt% component (E) or 0.5- 5wt% component (A), 0.5-5wt% component (B), 20-45wt% component (C), 1-8wt% component (D) and 45-60wt% component (E).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coating agent for improving the surface condition of clay tiles, particularly water absorption and water permeability.

It is natural for roofing materials to prevent water from seeping through to the back of the roof tiles, but in reality, water can seep through to the back of the roof tiles, rotting the wood71, and causing leaks. Many complaints are heard.

In order to improve the water permeability of such tiles, for clay tiles, the clay used as the base material must be thoroughly crushed, mixed, and vacuum degassed.
If the clay is further sintered at the optimum firing temperature and firing time, a significant improvement can be made, but this alone will not be sufficient to achieve the purpose.

This is because water permeation through the tiles is due to the pores penetrating the base, and no matter how optimal firing or sintering conditions are selected, it is impossible to wipe out the pores penetrating the base.

Therefore, the inventor examined the relationship between water absorption and water permeability for commercially available clay tiles using an absorption/water permeability tester as shown in the drawing, and found that tiles that are difficult to see through water absorption speed are extremely slow. There was found. Naturally, such tiles also have extremely low water permeability. The measurement method using the absorption/water permeability tester was as follows.

The volume of water per unit length in the glass capillary tube 1, which is graduated in groups, is measured in advance × (at / 1
111). In the case of a water permeability test, sample 2, which has been subjected to normal water absorption based on the water absorption test of JIS A3208, is wrapped in a plastic bag with a hole equal to the inner diameter of the cylinder and then placed on a support stand 3, and a rubber backing 4, a rubber stopper 9, Place the glass capillary tube 1 and the cylinder 5 with the Nigacock C1°C2 on it and tighten the screw 6 firmly. Nigacock himself, C2
To open, pour water from the tank 7 through the rubber tube 8 into the cylinder, and when the water line is above C2, turn C2 on. The water level further rises in the glass capillary tube 1 and closes Ct near the eye aO. As time passes, the water level in the glass capillary decreases. In other words, the length by which the water level drops is the water permeability.

Based on these facts, we conducted various studies on how to reduce the water absorption rate and produce tiles with extremely low water permeability, and as a result, we were able to achieve this goal by applying a thin layer of glaze with a specific composition to the tile base. , we have completed the present invention.

The gist of the present invention is mainly made of low-expansion glass,
Notified as an essential ingredient 203 + 820'3 e'S
1C) Contains 2 in ``A fabric agent that improves the water absorption and permeability of clay tiles''.

That is, the present invention provides 1) oxide compositions of Na2O and K2O.

One type of Li2Q or its (more than 2 to 10%, Cab,
One or more of MgO*Bad, ZnO, SrO is 0-8%, A12035-15%, B2O33-20
%, 5iO2 50 to 78%.A coating agent for improving water absorption and water permeability for clay roof tiles. 2) Oxide composition is 2-7% of one or more of Na2O, K2O, Li2O, pbo and CaO, MgO, Bad, Zn
The total amount of divalent oxides selected from O, SrO is 2~
30%, 7V#2032~・10chi, B2O33~15
H. A coating agent for improving water absorption and water permeability for clay roof tiles, characterized by having a 5iOa content of 50 to 78%. 3) The oxide composition is 0.5 to 5% of one or more of NazO, K2O-Li2O, and Cao.

One or more of MgO, Bad, ZnO, SrO is 0.5 to 5 inches, A720320 to 45 inches, B2O31
The present invention relates to three coating agents for improving the surface of clay roof tiles, which are characterized by having a content of 5i0245 to 60%.

The application method of the coating agent of the present invention is to apply the coating agent, which has been pulverized and mixed using a wet method to adjust the concentration, to one or both sides of the clay tile base for ceramic sleeve tiles, and then glaze it and dry and fire it. Ibushi tiles are coated on one or both sides of the clay tile base, then dried, fired, and smoked.

For example, after applying a thin layer of the first or second coating agent of the present invention, the concentration of which has been adjusted, to a clay tile base, a normal glaze is applied and fired at 950 to 1250°C in a furnace in an oxidizing atmosphere. or a first or second concentration-adjusted;
Alternatively, after applying a thin layer of the third coating agent to the clay tile base, it is fired at 950 to 1250°C in an oxidizing atmosphere furnace, and then smoked in a reducing atmosphere at 800 to 900°C, resulting in an improved clay tile replacement. It will be done.

In the present invention, the oxide composition of the coating agent for improving water absorption and water permeability is limited as described above for the following reasons. That is, the water absorption and water permeability of tiles are due to the countless pores that penetrate through the tile base and are present in the base of the tile. Therefore, water absorption and water permeation should be significantly reduced by blocking the pores that penetrate the substrate or by taking measures to prevent water from entering the pores that penetrate the substrate, but this is extremely difficult and rarely yields good results. stomach. In order to close the pores penetrating the base material during firing, it is necessary for the coating agent to maintain an appropriate viscosity during firing and maintain an expansion coefficient close to that of the base material. For this purpose, as a result of experiments on coating agents of various compositions, a preferable and appropriate range was experimentally confirmed, and the first to
The third composition has the above-mentioned composition range including ke20s*B20315to2 as an essential component.

Next, the present invention will be specifically explained with reference to examples.

Example 1 336 parts of anhydrous borax, 416 parts of Kanamaru feldspar, 115 parts of limestone, 84 parts of silica, and 49 parts of soda ash were thoroughly mixed,
Melt at a temperature of ``O±20''C, cool with water and dry.
A positive 1 frit of sodium borosilicate glass shown in No. 1 was obtained.

Nn1 frits) 30 parts, low expansion borosilicate glass 50 parts,
After weighing 20 parts of Frogme clay, 0.5 parts of sizing agent, and 100 parts of water and wet-mixing and pulverizing, 200 meshes were passed through the entire surface.
The water absorption and water permeability improver shown in 2 was obtained.

Table 1) Oxide composition of Nllll (7 parts%) Na2
0 CaOAJl=203 B2O3S i02
Total 20.1 6.8 8.1 24.7
40.3 100 table-2r! &Water, oxide composition of water permeability improver (wt%) KsNa20 CaOA#z0
3 B2O3S tow Total 9.9 4.2
8.9 14.2 62.8 100 Dilute the obtained improver with water once every 35 times to adjust the concentration, apply it by hand to the surface of the glazed tile manufacturing method, and after drying, apply glaze using the conventional method. After applying the glaze using the method described above, the tile was fired at 1000° C. for about 24 hours in a tunnel furnace in the oxidation range to obtain a glazed tile coated with a water absorption and water permeability improver.

One representative piece of the obtained tiles was cut out and the water permeation rate I was measured using the testing device shown in Figure 9. The results are summarized in Table 5 together with comparative examples.

Example 2 5 parts of commercially available lead silicate glass cullet, 70 parts of low-expansion borosilicate glass, 25 parts of clay, 0.5 part of sizing agent, and 100 parts of water were weighed, and after wet mixing and pulverization, 200 parts of The leaded water absorption and permeability improver shown in Table 3 was obtained by passing it through a mesh sieve. Work on the base material, apply it to the back side, apply glaze after drying, and heat in a tunnel furnace in an oxidizing atmosphere for 11 days.
A glazed tile was obtained by firing at 50° C. for about 20 hours. The results of water permeation rate are shown in Table-5.

Table-3 Oxide composition (wt%) of leaded water absorption and water permeation improver K
*Na2OCaOPbOA1203 B2O35i
024.1 1.0 5.2 7,7 1
0.1 71.9 Example 3 The water absorption and water permeation preventive agent obtained in Example 1 was applied to the clay tile base.
It was coated on both sides with a concentration of about 100 ml, fired at 950°C in a shuttle furnace in an oxidizing atmosphere, and then smoked in a reducing atmosphere at 890°C to obtain an oxidized roof tile.

The water permeability rate of the obtained ibushi tiles was measured. The results are shown in Table 5.
Shown below.

Example 4 34 parts of low expansion borosilicate glass, 66 parts of clay, and 0.5 parts of glue
100 parts of water were added, and the mixture was passed through a 200-mesh sieve through a wet mill to obtain a slurry-like coating agent. The oxide composition of the obtained coating agent is shown in Table 4. The concentration of this coating agent is 40
After adjusting the consistency, it was applied thinly and uniformly to the surface of the clay tile with a brush and oxidized and fired at 980°C in a Schottl furnace, and then smoked in a reducing atmosphere at 850°C to obtain an oxidized tile. The surface of the obtained Mebushi tile was very smooth and had a moderate gloss compared to conventional products, making it extremely beautiful.

Table-4 Oxide composition of coating agent (@Na2OCaOBaOB2O3A403 5i02
3', 4'1.2 0.8 2.8 35,2
56.6 Comparative Example 1 The water absorption and water permeation preventive agent obtained in Example 1 was applied to a clay tile base at 30%
The glaze was coated on one side (surface) with a glaze-like consistency, and fired in a tunnel furnace in an oxidizing atmosphere at 1,000°C for about 24 hours, resulting in a tile with a glaze that had never been seen before. This was similarly subjected to a water permeability test using the testing device shown in the drawing. The results are shown in Table-5.

Comparative Example 2 A commercially available sleeve tile manufactured by a conventional glazed tile manufacturing method was obtained, and the water permeation rate was measured in the same manner. Commercially available oxidized roof tiles were also obtained and the water permeation rate was measured in the same manner. The results are shown in Table-5.

Table 5 Water permeation rate measurement results Commercially available silver glaze tile (Comparative Example 2) 0.042
Commercially available ibushi clay tiles (Comparative Example 2), 0.
Glazed tile using only 030 water permeability improver (Comparative Example 1)
Silver color sleeve tile using 0.617 water permeability modifier (Example 1) Blue-green sleeve tile using 0.007 water permeability modifier (
Example 2) Ibushi tiles using 0.009 water permeability improver (Example 3) '0.005 Manufactured using the water absorption and water permeability improver of the present invention as shown in Examples and Comparative Examples in Table-5 The water permeation rate of the roof tile was extremely low, and the effectiveness of the present invention is clear, but the implementation of the present invention also provides more advantageous characteristics.

That is, when the water absorption and water permeability improver of the present invention is applied and fired, a small amount of penetration occurs on the coated surface, and therefore, when applied to the surface of clay tiles, water absorption and water permeation due to outdoor wind and rain and melting snow are suppressed. do. In addition, if applied to the back side, moisture that evaporates from indoors will be absorbed to the extent that it does not condense on the back side of the tile, and as the temperature rises, the moisture inside the tile can escape through a so-called ``breather'', reducing the risk of frost damage. It has the following advantages.

[Brief explanation of the drawing]

The figure shows a device for testing the water absorption and permeability of clay roof tiles. 1...Glass capillary tube 2...Sample (in plastic bag) 3...Support stand 4...Rubber/ξtsukifugu 5...Cylinder 6...Tightening screw 7...
Tank 8...Rubber pipe 9...Rubber stopper C1...Three-way cock C2...Two-way cock Agent Patent attorney Satoshi Sasaki □, 1

Claims (1)

[Claims] 1. The oxide composition is 2 to 10% by weight of one or more of Na2O, K20* and Li2O (hereinafter all weight%)C
ab. One or more of MgO, Bad, ZnO, SrO is o~8chi, A72035~15%, 82035~20
%, 5i0250 to 78%, and is used for clay roof tiles to improve water absorption and water permeability. 2. Oxide composition is 2-7% of one or more of Na2O, K2O, Ij20, pbo, Cab, MgO, B
ad, Zn (total amount with divalent oxide selected from LSrO is 2 to 30%, Ajh Oa 2 to 10%, B2
A coating agent used for clay tiles to improve water absorption and water permeability, characterized by containing O35 to 15% and 3i0250 to 78%. 3. Oxide composition: 0.5-5% of one or more of Na2O, K20e and Li2O, Cab, MgO, Ba
d, one or more of ZnO and SrO is 0.5 to 5
%, A72o32o~45%, B2031~8%, 5i
A coating agent for improving the surface condition of clay roof tiles characterized by having a content of 45 to 60% Oz.