JPS5939781A - Clay roof tile discolor prevention - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The object of the present invention is to provide a simple and inexpensive treatment method for retaining the silver-black surface characteristic of clay roof tiles.

When clay tiles get wet, the ingredients contained inside them seep out and adhere to the surface, causing uneven coloring and discoloration, resulting in lower-priced tiles.

This phenomenon occurs on almost all roof tiles after a few days of rain, and is called ``rust'' because the discoloration caused by iron components is particularly noticeable, and is a serious concern in the industry.

Therefore, suppressing the formation of rust and preserving the beauty of clay tiles has been a long-standing research topic in the tile manufacturing industry, and each manufacturer has traditionally used its own secret treatment methods.

However, due to circumstances such as the fact that a complete treatment method had not been established, the use of natural materials that have become difficult to obtain in recent years as a treatment agent, and the exclusive use of labor-intensive treatment methods, In recent years, treatment methods using chemicals have been actively studied.

However, the chemical treatment method was not satisfactory.
In order to completely suppress "rust", the current situation is to apply an acrylic paint using a solvent and cover the tiles with an acrylic film.

Treatment with this acrylic paint is important for safety and hygiene,
Considering that this method has no choice but to be adopted even though it is disadvantageous from both the viewpoint of workability and the price of the processing agent,
It is easy to imagine how important the problem of suppressing rust is.

The present invention has been made in consideration of these circumstances, and basically involves immersing fired clay roof tiles in an aqueous solution of water-soluble higher fatty acid salts, such as sodium stearate, and then pulling them out and drying them. It is possible to create clay roof tiles that are completely rustproofed using relatively inexpensive chemicals and extremely simple operations.

The higher fatty acid salt used in the present invention is R-COO
It is expressed in the form of Me, which combines with higher fatty acids to form water-soluble salts such as potassium, calcium,
It is well known that it easily combines with metals such as aluminum or magnesium to form insoluble forms such as calcium stearate.

Although the mechanism of the excellent rust prevention achieved by the treatment of the present invention has not been clarified, it is probably due to components such as calcium, aluminum, or magnesium present inside or on the surface of tiles, and higher fatty acids, which are components of the treatment agent used in the present invention. The metal soap, which is water-insoluble and water-repellent, is combined and precipitated, effectively filling the pores inside the tile and creating rust.
In addition to suppressing the elution of components such as iron that cause rust, the metal soap covers the tile surface and is thought to prevent the adhesion of "rust" components.

In fact, the treatment of the present invention has the effect of increasing the gloss of the tile surface and increasing the number of nests.

In the clay tiles treated according to the present invention, "rust" was observed on only 3 out of 1000 tiles after 2 years of outdoor exposure, whereas for comparison, chemical treatment currently used After being treated with "Sabinon All" (manufactured by Daionuki Sangyo Co., Ltd.), which is the most commonly used product, and exposed in the same way, 65 out of 100 sheets were treated with "rust" in just one month. Occurrence was observed.

The treatment method of the present invention as described above is extremely simple.

That is, a clay tile that has been taken out of the kiln and has been suppressed from soot may be immersed in an aqueous solution of a higher fatty acid salt of about a few percent for several minutes, then taken out and dried.

Note that the concentration, time, and drying temperature are not particularly specified and can be arbitrarily selected.

In order to enhance the treatment effect of the present invention, in order to help the treatment agent penetrate into the tile interior and to eliminate traces of foam adhering to the tile surface, surfactants and antifoaming agents are used in combination or treatment. Before and after use may be desirable.

In addition, in order to further improve the water repellency achieved by the treatment of the present invention,
It is also recommended to convert tiles treated with the present invention into water-repellent metal soap by immersing them in slaked coal liquid or the like.

Furthermore, it can also be combined with a water repellent treatment using a conventionally used silicone-based treatment agent.

As described above, the present invention allows the use of inexpensive and widely used chemicals, and many of the other treatment liquids for the same purpose are strong acids and strong alkalis that are difficult to handle, and the treatment time is too long, causing the color of tiles to change.
Although the present invention has the disadvantage of causing a change in gloss, it also has the advantage of being able to work under safe and easy conditions.

In addition, since the present invention can be treated with an aqueous solution of a single solute,
It is easy to adjust the structure of the treatment liquid to keep it constant even if the dipping operation is repeated.

As described above, the treatment method of the present invention not only provides an excellent discoloration prevention effect, but is also extremely advantageous from the viewpoint of workability and profitability. It can be said that the significance is great.

Examples of the present invention will be described below.

Example: A total of 1,000 tiles, 250 tiles from each lot, were extracted from clay tiles that were fired in 4 lots with 1,000 tiles in each lot, each with different raw clay.After suppressing the soot, It was subjected to the test.

Note that the surfaces of all of these test tiles exhibited a black and silver color with a metallic feel.

Test 1. 25 pieces were arbitrarily taken from each lot and placed in a 5 g/l sodium oleate aqueous solution at 20°C.
When a total of 100 test tiles were soaked for 10 minutes, dried at room temperature, and then exposed outdoors for two years, none of them developed rust, and all tiles had an initial metallic appearance. was maintained.

Test 2. When the same test as Test 1 was conducted except that the temperature of the treatment liquid in Test 1 was changed from 20° C. to 70° C., the same results as Test 1 were obtained.

Test 3. The concentration of the treatment solution in test 1 was changed from 5 g/l to 0.5 g/l.
When a test was conducted in the same manner as in Test 1, ``rust'' was observed on 3 tiles, but the remaining 98 tiles did not develop ``rust'' and maintained their initial metallic appearance.

Test 4. Test 1 by changing the immersion time of Test 1 from 10 minutes to 1 minute.
When the test was conducted in the same manner as in Test 1, the same results as in Test 1 were obtained.

Test 5. A test similar to Test 1 was conducted using sodium stearate, potassium stearate, sodium palmitate, and sodium laurate instead of sodium oleate. However, the same results as in Test 1 were obtained.

Test 6. A test similar to Test 2 was conducted using sodium arachidate instead of sodium oleate, and the same results as Test 2 were obtained.

Test 7.5 g/l aqueous solution of sodium oleate and 5
A test similar to Test 1 was conducted using a treatment solution mixed in the same amount with g/l aqueous solution of sodium stearate, and the same results as Test 1 were obtained.

Patent applicant: ■ Kawabata

Claims (1)

[Claims] A discoloration prevention method characterized by treating fired clay tiles with salts of higher fatty acids.