JPS5811394B2 - Manufacturing method for decorative roof tiles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing decorative roof tiles, and is useful for manufacturing ridge tiles, oni tiles, eave tiles, corner tiles, and the like.

Cement tiles are well known as one type of Japanese tiles.

To manufacture this tile, a relatively hard mortar containing a 1:3 mixture of cement and sand is placed on the template of a tile making machine.
This mortar is pressed into the template by rollers, excess mortar is scraped off, the thus formed product is removed from the tile making machine along with the template, and after drying to some extent, it is forcedly cured by heating.

However, in the production of this tile, cracks are likely to occur when the molded product dries, and this cracking is particularly prone to occur in tiles with complex shapes such as ridge tiles, ridge end decorative tiles, oni tiles, eaves tiles, corner tiles, etc. Remarkable.

The cause of this cracking is that during drying, moisture evaporates only from the surface of the molded product, making it difficult to dry the entire molded product uniformly.

Furthermore, the roof tiles obtained as described above also have drawbacks such as relatively low mechanical strength, unsatisfactory insulation properties, poor cold resistance, and relatively large weight. .

In view of the current situation, the applicant of the present application first proposed the use of cement 30.
~35%, silica sand 22-25%, asbestos cement scrap 30-15%, foamed aggregate e.g. foamed silica sand 15-20%
, 17-9% asbestos is mixed, and this is 3-10% by weight.
The hardened product is molded into the shape of a roof tile with 200 to 60% water.
We proposed press molding at a pressure of 0 kg/cm2, drying this molded product, and then subjecting it to forced curing.

In this tile manufacturing method, the amount of water added is 3 to 10%.
The fluidity of cement must be sufficiently suppressed, and the molding pressure must be 200 to 600 kg/cm2.
Because the impregnation of the cement paste into the foamed aggregate is sufficiently suppressed, the compact after pressing has the following properties:
The foamed aggregate is present in a porous state that is not filled with cement paste.

Therefore, due to the porosity of the foamed aggregate, water evaporates from the inside of the molded product when drying the molded product, and as a result, the entire molded product dries uniformly, which eliminates the above-mentioned crack occurrence. .

Since the tiles obtained by the above method contain foamed aggregate in a porous state, they have excellent heat insulation properties and are also lightweight.

Furthermore, since it contains asbestos fibers, it has excellent mechanical strength.

Furthermore, even if moisture infiltrates the foamed aggregate, the strength of the grains of the aggregate is high, so cracks will not occur due to stress when the moisture freezes and thaws.

By the way, roof tiles are required to be colored and decorated, and this makeup is required to have a semi-gloss, calm appearance.

One possible method for this cosmetic method is to spray a colored cement-based paint containing inorganic particles with relatively large diameters.

According to this makeup method, the makeup surface is made uneven, so
Makeup with less shine is possible.

In addition, since this decorative material contains cement, if the above spraying is performed on an uncured product, the decorative material will be firmly bonded to the cured product when the uncured product is cured. , it is possible to apply makeup with excellent peel strength.

In the production of roof tiles previously proposed by the applicant, the above-mentioned spray cosmetic method may be used to decorate the roof tiles, and for this reason, the inventors have proposed that the molded product after press molding, that is, the foamed aggregate When the above-mentioned colored cement-based paint containing granules was sprayed onto an unhardened cement molded product that was still in a porous state and dried, the colored cement-based paint spread to the porous skin of the unhardened cement molded product. It was possible to apply makeup with extremely high peeling resistance.

However, for three-dimensional ridge tiles, etc., until the colored cement-based paint dries, the particles in the paint shift due to their weight on both sides of the ridge tile, etc., and the particles become matte. I learned that it is not possible to effectively demonstrate the effects.

The method for producing a decorative roof tile according to the present invention prevents the above-mentioned shift and movement of the granules when decorating the roof tile by spraying a colored cement-based paint containing granules, and allows the granules to adhere uniformly. This is a method that allows you to apply subdued makeup with little shine overall.

Furthermore, according to the present invention, makeup with excellent water resistance and peeling resistance can be applied.

That is, in the method for manufacturing decorative roof tiles according to the present invention, uncured cement roof tiles are preheated to about 40 to 70°C, and the diameter is 1.
．． An aqueous dispersion of a resin and a cement coloring material containing inorganic particles of 5 to 0.1 mm is sprayed onto the surface of the above-mentioned 8 preheated roof tiles, and after drying, a colored resin liquid is further applied. This method is characterized in that the roof tiles are then cured in an autoclave.

The aqueous dispersion of resin and cementitious coloring material containing inorganic particles used in the present invention includes the following combination of cementitious coloring material and silica sand (colored silica sand) with a diameter of 1.5 to 0.1 mm.
A resin emulsion made by mixing 1:1 with 65 parts of water to 100 parts of a water-dispersible resin, such as an acrylic resin, is prepared.
A mixture of the above mixtures in a ratio of 2 to 3:1 can be used.

Contains a cement-based colorant Silica flower 7 parts Whiten 12 Cement 9 Silica sand 3 Asbestos 2 Pigment Rest In the present invention, uncured roof tiles contain foamed aggregate in a porous state. Contains.

Therefore, = portion of the sprayed paint is impregnated into the porous skin of the uncured roof tile, and the cement particles and resin in this paint are
During curing, it binds to the porous structure of the roof tile's skin, making it possible to apply a makeup with excellent peeling resistance.

Furthermore, since the water-dispersible paint used in the present invention contains resin, it has high viscosity.

Since this paint is sprayed onto preheated uncured roof tiles, the water in the paint adhering to the surface of the molded product is immediately evaporated and scattered, further increasing the viscosity of the adhering paint.

Because of the compaction, the adhered particles do not fall off due to their own weight, and the particles can be adhered uniformly.

In the present invention, the preheating temperature of uncured roof tiles is set at 40 to 70°C.
The reason for limiting the temperature to 40°C is that below 40°C there is no effect on the above-mentioned evaporation and scattering of water, and above 70°C, the cement in uncured roof tiles undergoes a rapid hydration reaction, and internal stress due to this hydration reaction occurs. This is because cracks occur in the roof tiles.

After the aqueous dispersion of granule-containing resin and cement coloring material is sprayed onto roof tiles as described above, this spraying solution is dried, and then colored resin solution, such as acrylic A colored emulsion of resin is applied by spraying.

In this case, since the colored emulsion is sprayed after the aqueous dispersion coating film of the resin or cement coloring material has dried, there is no color staining due to mixing of re-paint.

The coating film of this colored emulsion is uneven due to the uniformly adhered particles described above, resulting in a decorative surface with little gloss.

In addition, the colored emulsion coating is made extremely thin, and the color effects of the base coating, that is, the coating of resin and cement-based coloring materials, appear.

Therefore, the hue is adjusted.

The uncured roof tiles decorated as described above are cured in an autoclave and made into a final product.

This autoclave curing is usually performed by heating with saturated steam at 5 to 8 atmospheres for about 10 hours.

During this autoclave curing, the outermost resin coating is baked, resulting in a coating with excellent water resistance.

As described above, according to the present invention, it is possible to apply a colored makeup to roof tiles that is less glossy and has excellent peeling resistance and water resistance.

Claims (1)

[Claims] 1. Preheat an uncured cement roof tile to about 40 to 70°C, and add an aqueous dispersion of a resin and a cement coloring material containing inorganic particles with a diameter of 1.5 to 0.1 mm to the preheated roof tile. A method for producing a decorative roof tile, which comprises spraying it on the surface of the roof tile, drying it, further applying a colored resin liquid, and then curing the roof tile in an autoclave.