JPH0733299B2 - How to color cement products - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for coloring a cement product.

[Conventional technology]

BACKGROUND ART Conventionally, building products such as blocks, wallboards and roofing materials have been very widely used as cement products such as fiber reinforced cement.

By the way, the above cement product has water absorbency as it is, and since the surface of the substrate is grayish white to gray black and is achromatic and poor in designability, the surface has water resistance to impart water absorbency resistance and aesthetics. It is usual to paint with various paints in various colors.

As the coating means, a liquid or powder coating material prepared by mixing a coloring pigment with cement is supplied to the surface of the cement product, and in the case of a powder raw material, water necessary for the hydration reaction is supplied and then autoclave curing is performed. There is known a method of curing, or a method of adding a color pigment to cement and adding an emulsion resin to form a liquid coating material on the surface of a cement product and curing it by natural curing.

[Problems of conventional technology]

However, the former coating method has difficulty in water resistance or durability because the coating layer is cured by the hydration reaction of cement, and the latter coating method is superior in this respect.

However, since the latter one using the emulsion resin is a liquid raw material, the products cannot be stacked until the coating film is cured after coating, and there is a drawback that the handling becomes troublesome.

[Problems to be Solved by the Invention]

In view of the above problems, the present invention has been made for the purpose of providing a method for coloring a cement product, which enables stacking of products immediately after coating, and has excellent strength such as water resistance and durability after curing. Is.

[Technology that has solved the problem]

That is, the method for coloring a cement product of the present invention is a cement
Supply 3 to 100 parts of powder coating consisting of thermoplastic resin to 100 parts of powder material to the surface of cement product,
It is characterized in that water necessary for the hydration reaction of the cement is added and the autoclave is aged at a temperature above the melting point of the powder coating made of the thermoplastic resin.

[Action]

In the present invention, the target cement product may be any product as long as it is formed by using cement as a main component, and for example, a roofing material, a wall board, a block, or the like.

In the present invention, as the material for coloring the above-mentioned cement product, one obtained by adding 3 to 100 parts of powder coating material made of a thermoplastic resin to 100 parts of cement is used.

Addition of 3 to 100 parts of powder coating made of thermoplastic resin to 100 parts of cement and cement is not possible to impart the required water resistance to the coating film and sufficient coloring cannot be achieved if it is less than 3 parts. This is because if it is more than 100 parts, the amount of cement compounded will decrease in inverse proportion to this and the coating film strength will decrease.

The above powder material is supplied as a layer on the surface of the product as a powder without adding water or as water, and in the case of powder, it is thermoplastic after supplying the water necessary for the hydration reaction. Autoclave is cured at a temperature above the melting point of the powder coating made of resin.

At this time, the cement component undergoes a hydration reaction during autoclaving and is hardened, and at the same time, the powder coating material is also melted by heat, and they are naturally integrated to form one coating film.

Therefore, the cured coating film exhibits strength due to the cement hydration reaction, and at the same time, sufficient water resistance is imparted by the cooling-cured thermoplastic resin.

Reinforcing fibers such as pulp and asbestos may be added to the cement.

〔Example〕

 Next, an embodiment of the present invention will be described.

A powder material having the composition shown in Table 1 was uniformly mixed with a high shear mixer, and the obtained powder material was sprayed on the cement plate surface at a rate of 500 g / m ^{2 by} a sprayer, and water was sprayed. Pressed with a press.

In Table 1, Comparative Examples use iron oxide red pigments as coloring raw materials.

The colored coated plate obtained above is naturally cured for 2 hours, then 8 kg /
The autoclave was aged under the conditions of cm ² × 180 ° C × 10 hours.

The results of the coating film test after curing the coating film are shown in Table 2.

As is clear from Table 2, the products of the present invention achieved good results in all test items.

The "*" defect in the comparative example means that effluent was remarkably generated during autoclave curing, and recoating was required again to obtain a beautiful surface.

〔effect〕

As described above, according to the present invention, the coating film is composed of the thermoplastic resin powder which is once melted with the hardened cement and hardened in the state of being mixed with the cement matrix, so that the coating film has the strength of the cement and the water resistance of the resin. Thus, it is possible to obtain a coating film having both excellent properties and strength and water resistance.

Further, in the case of carrying out the present invention, since the coloring material in a dry powder state can be sprayed on the surface of the product and can be hydrolyzed and cured later, it is possible to stack the products immediately after supplying the coloring material, and the handling is very easy. It has effects such as being easy.

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C04B 24:24) Z

Claims (1)

[Claims] 1. A powder material obtained by adding 3 to 100 parts of a powder coating made of a thermoplastic resin to 100 parts of cement is supplied to the surface of a cement product, and water necessary for the hydration reaction of the cement is supplied. A method for coloring a cement product, which comprises adding and curing the autoclave at a temperature equal to or higher than the melting point of the powder coating made of the thermoplastic resin.