JPS6140861A - Mortar composition - 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 present invention relates to a mortar composition, and more particularly, to a mortar composition comprising a polymer dispersion with excellent elasticity and colored sand with excellent colorability. be.

Conventionally, a mortar composition in which Portland cement is blended with a polymer dispersion and a suitable aggregate is known as a so-called polymer cement mortar. This mortar composition has excellent water resistance and is usually used as mortar for decorating the surfaces of flooring materials, such as interior or exterior walls of buildings, trains, ships, etc. Therefore, by spraying mortar onto a base material such as a metal plate, foamed concrete board, gypsum board or synthetic resin board, the mortar is coated onto the surface of the base material, but the mortar after hardening has the disadvantage of being susceptible to cracks. There are two possible causes for this: one is caused by shrinkage of the mortar itself, and the other is caused by the lack of elasticity in the mortar when the substrate itself bends.

In view of the above-mentioned circumstances, the present inventors investigated various ways to prevent the occurrence of mortar cranks by improving the elasticity of mortar while maintaining the characteristics of conventional polymer cement concrete. The present inventors have discovered that when a mortar composition prepared by mixing in a specific ratio is used, the occurrence of cracks and cracks due to shrinkage of the mortar itself can be significantly suppressed, and the present invention has been completed.

In this case, the earlier application, Japanese Patent Application No. 58-104623, states that it is okay to add a pigment as a coloring method, but in the same coloring method as this conventional colored cement mortar, pigment dispersion, pigment dispersion, There was a problem in that color unevenness occurred in the mortar layer due to differences in pH distribution, drying time, etc.

Furthermore, the terms Portland cement and alumina cement simply refer to black cement, which is inappropriate when attempting to color mortar.

The object of the present invention is to prevent color unevenness in coloring by using colored sand, and to use it as a thinly painted finishing material or decorative material that has the characteristics of polymer cement concrete and low elasticity.

That is, the gist of the present invention is: ■ white cement, ■ white alumina cement 0.5 to 5 times the weight of white cement, and ■ 0.3 to 5 times the weight of white cement.
2 times the weight of gypsum and ■ 0.1 to 1 times the weight of polymer dispersion as a polymer component based on the sum of white cement, white alumina cement, and gypsum.
This mortar composition is characterized by containing colored sand as an aggregate in an amount of 1 to 4 times the weight of the sum of white cement, white alumina cement, and gypsum.

The present invention will be explained in detail below.

In the present invention, it is essential that the mortar composition contains five components: white cement, white alumina cement, gypsum, polymer dispersion, and silica sand or colored sand. As white cement and white alumina cement, common commercially available products can be mentioned.

White alumina cement is defined as having an iron oxide content of less than 0.5%. The content of white alumina cement is 0.5 to 5 compared to white cement.
times the weight, preferably 1 to 3 times the weight, and when the content of white alumina cement is less than the above range,
When the mortar is applied, not only the curing speed is slow, but also high strength cannot be obtained. On the other hand, if the amount is more than the above range, a mortar with good elasticity cannot be obtained and cracks are likely to occur, so it is preferable. do not have. One of the features of the present invention is that white cement and white alumina cement are used in combination in a specific ratio.

Furthermore, in the present invention, gypsum is present in addition to the above-mentioned cements. Both gypsum hemihydrate and gypsum trihydrate can be used in the present invention, but gypsum hemihydrate is more effective. The content of gypsum is 0.3 compared to white cement.
~2 times by weight, preferably 0.5 to 1.3 times by weight.

Due to the presence of this gypsum, it is possible to obtain a good mortar layer that is even more excellent in elasticity, has high strength, and is less likely to generate cranks.

Next, the polymer dispersion used in the present invention is not particularly limited as long as it is aqueous, and various conventionally known ones can be used, but usually polyacrylate, polyvinyl acetate, etc. , thermoplastic resin emulsions such as polyvinylidene chloride-polyvinyl chloride, polyvinyl propionate, polyethylene-polyvinyl acetate, polypropylene; thermosetting resin emulsions such as epoxy resins; asphalt, rubber asphalt,
Bituminous emulsions such as paraffin; chloroprene rubber, styrene-butadiene rubber, methyl methacrylate
Examples include butadiene rubber, synthetic rubber latexes such as butadiene rubber, and mixtures thereof. The content of these polymer dispersions is based on the sum of white cement, white alumina cement, and gypsum.
0.1 to 1 times the weight of the polymer component, preferably
0.2 to 0.8 times the weight, and if this content is less than the above range, the water resistance of the mortar will be poor and the elasticity will be significantly lower; Although it improves the elasticity of the mortar, it is undesirable because it has the drawbacks of stiffness and poor strength and durability.

In addition, as for the type of aggregate, colored sand of size 5 to 8 is usually used, and it can be colored in any color depending on the purpose and location. The content of aggregate is usually 1 to 4 times, preferably 1 to 2 times the weight of the sum of white cement, white alumina cement, and gypsum. This colored sand is usually made from, for example, No. 5 to No. 8 silica sand, river sand, crushed sand, etc., and is coated with a paint having good water resistance, alkali resistance, and weather resistance.

In the present invention, in addition to the above-mentioned components, to the extent that the characteristics of the present invention are not lost, for example, a dispersant, The mixture is prepared in a conventional manner to give a concentration of 0 to 0.
This can be carried out by sufficiently kneading with 2 times the weight of water and then applying the mixture with a trowel.

As described above, according to the present invention, it is possible to obtain a good mortar with significantly less occurrence of cracks due to shrinkage of the mortar or deflection of the base material. In the present invention, one of the reasons for obtaining mortar with such excellent elasticity is that in the case of the specific composition of the present invention, (3CaO-Al2O
:l' 6 I20) and (CaSO,' 2HzO) are generated, which further generates ettringite (3Ca
This is because O-AI20:1.3CaSO4) is generated. In other words, since ettringite is a needle-like crystal, the resin component enters the gaps between the needle-like crystals, resulting in a structure that has excellent elasticity and is resistant to cracks. Moreover, since ettringite has a large amount of crystallization water, it is preferable because it has excellent nonflammability and flame retardancy even when used as a mortar containing a relatively large amount of organic matter. In addition, when using white cement, it can be said to be better as a finishing material because it has sufficient elasticity even if the amount of resin is smaller than that of plaque cement. Furthermore, since the present invention contains alumina cement, the mortar is hardened to the inside in a short time, so the initial strength of the mortar is high and the workability is good.

In addition, because colored sand is used as the coloring material, and because it is used as a finishing material for thin coating, color unevenness may occur.
＜, Beautifully finished.

Therefore, the mortar composition of the present invention is particularly preferable as a mortar for finishing or decorating flooring materials.

Further, the substrate to which the mortar composition of the present invention is applied is not particularly limited, but excellent effects are exhibited when applied to metal plates such as iron plates, aluminum plates, or galvanized plates, for example. Of course, it goes without saying that it can be applied to surfaces made of concrete.

<Examples and Comparative Examples> A mixture of Portland cement, alumina cement, and gypsum shown in Table 1, and a mixture of the polymer dispersion shown in Table 1 and 200 parts of silica sand was mixed at 0.07 times the amount of these. of water for 0.1 hour, and then the kneaded mixture was applied onto a galvanized plate so that the thickness after hardening was 4 mm, and heated at 20°C, 565%
Curing was performed under RH conditions for 2 days and 5 days for the elasticity test, and for 2 days for the efflorescence test.

The mortar elasticity test was performed by bending the plate-shaped article having the mortar layer obtained in this manner by 120 degrees horizontally, and the cracks in the mortar layer were tested.

Table 2 shows the results of investigating the degree of occurrence of this phenomenon.

Next, a few drops of water were dropped onto the plate-shaped article having the mortar layer shown above, and the state of efflorescence was examined after it was left at room temperature for one day. The results are shown in Table 3.

In addition, white cement, white alumina cement,
Add 1% or 5% of pigment to the total overlap of gypsum and silica sand, or use colored sand instead of silica sand to make a plate in the same manner as described above, and check the state of color unevenness. The results of the investigation are shown in Table 4.

Table 1-1 Comparative Examples Table 1-2 Examples Table 1-3 Comparative Examples Note) The amount of polymer dispersion used indicates the weight ratio of the polymer component to the sum of Portland cement, alumina cement, gypsum, and aggregate. .

Margin below Table 2 Table 3 Margin below Table 4 Color unevenness test results Note) Evaluation of color unevenness test ○－・－No uneven color at all There is some color unevenness. ×－・・・－・There is considerable color unevenness.

Claims (1)

[Claims] 1 (1) white cement, (2) white alumina cement in an amount of 0.5 to 5 times the weight of white cement, (3) gypsum in an amount of 0.3 to 2 times the weight of white cement. and (4) 0 as a polymer component for the sum of white cement, white alumina cement, and gypsum.
．． A mortar composition characterized by blending 1 to 1 times the weight of a polymer dispersion, (5) appropriate colored sand as an aggregate, and (6) appropriate water. 2. The mortar composition according to claim 1, wherein the content of aggregate is 1 to 4 times the weight of the sum of white cement, white alumina cement, and gypsum. 3. The mortar composition according to claim 1 or 2, wherein the colored sand is silica sand No. 5 to 8 coated with a paint having good water resistance and alkali resistance. 4. The mortar composition according to claim 1, wherein the polymer dispersion is an aqueous thermoplastic resin emulsion.