JPH1142618A - Method for molding inorganic cured composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the possession of a high, uniform surface gloss by specifying the surface gloss and coefficient of linear expansion of a mold. SOLUTION: An inorganic cured composition is put into a mold and cured and molded to mold the inorganic cured composition. The surface roughness Rz [wherein, a ten point average roughness (JIS B 0601)] of the mold is made 0<Rz<=0.50 μm, and the coefficient of linear expansion β is made 0<β<2.5×10<-5> K<-1> . The material of the mold, if conditions are met, is selected and adopted. Practically, there are mirror-polished aluminum, chromium-plating- finished iron, stainless steel, glass of boron silicate glass, and others, and boron silicate is the optimum material which meets the conditions. The shape of the mold is appropriately selected into the required shape of a molding mold. A composition for molding can adopt an inorganic building material to be molded into a molding as a building material, and there are cement and an alkaline earth metal oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding an inorganic cured composition for civil engineering and construction, and more particularly to an inorganic cured composition having excellent surface gloss and a molded article having a uniform gloss. The present invention relates to a method for molding a cured composition.

[0002]

2. Description of the Related Art Conventionally, when an inorganic cured composition such as cement or alkaline earth metal oxide is placed in a mold and cured and molded into a molded product, the molded product not only has a low surface gloss but also has a low surface gloss. There is a problem that the surface gloss becomes uniform.

[0003]

As a means for solving this problem, it is conceivable to polish the inside of a mold made of an alloy to a mirror surface. However, polishing a metal surface is not only time-consuming but also requires polishing. However, in the case of a large mold, it was difficult to give uniform gloss to the entire surface of the molded article to be molded.

Accordingly, an object of the present invention is to solve this problem and to provide a method for molding an inorganic cured composition having a high and uniform surface gloss.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies on the above-mentioned problems, and as a result, by specifying the surface roughness Rz and the linear expansion coefficient β of a mold for molding an inorganic cured composition, a high level has been achieved. The inventors have found that a molded article of an inorganic cured composition having uniform surface gloss can be formed, and have completed the present invention.

That is, the present invention relates to a method for molding an inorganic cured composition in which an inorganic cured composition is placed in a mold and cured and molded, wherein the surface roughness Rz (10-point average roughness (J
ISB 0601)) is 0 <Rz ≦ 0.50 μm, and the linear expansion coefficient β of the mold is 0 <β <2.5 × 10 ⁻⁵ K ^−1. It is.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The surface roughness and the coefficient of linear expansion of the above-mentioned mold, which is a feature of the present invention, are specified because the surface gloss of the molded inorganic cured composition is high and uniform. This is to hold the value. This is because the surface gloss can be maintained at a high value by reducing the surface roughness, and the surface gloss can be made uniform by reducing the linear expansion coefficient.

[0008] A preferable value as the surface gloss of the above-mentioned inorganic cured composition molded article (60-degree specular gloss; JIS K710)
5) is 75% or more as the maximum value, and a preferable value for the variation (difference between the maximum value and the minimum value among a plurality of measurement values measured at each location) is 15 or less. In order for the inorganic cured composition to have such a value, the surface roughness R of the mold is required.
z (10-point average roughness (JIS B 0601)) is 0 <
Rz ≦ 0.50 μm (more preferably, 0 <Rz ≦ 0.
30 μm), and the linear expansion coefficient β is 0 <
β <2.5 × 10 ⁻⁵ K ⁻¹ (more preferably, 0 <β <2.
0 × 10 ⁻⁵ K ⁻¹ ).

The material of the mold can be appropriately selected and employed as long as it satisfies the above conditions. Specifically, there are mirror-polished aluminum, chrome-plated iron, stainless steel, glass such as borosilicate glass, and the like, and borosilicate glass is the most suitable material that meets the above conditions. The shape of the mold is appropriately selected according to the required shape of the molded body.

As the above-mentioned inorganic cured composition molded in the present invention, an inorganic building material molded into a molded article as a building material can be appropriately employed, and specific examples include cement and alkaline earth metal oxides. .

As the above cement, various portland cements, blast furnace cements, white cements, alumina cements, magnesium phosphate cements, and magnesia oxychloride cements can be used.

The alkaline earth metal oxide includes, for example, MgO, CaO, SrO, BaO and double salts thereof (for example, CaO.MgO), or a combination of two or more thereof. Among the alkaline earth metal oxides, MgO is most easily used in view of the pot life and strength, and the type of the alkaline earth metal oxide is soft burn (having a small bulk density). There are light burning and hard burning (hard burning with a large bulk specific gravity), and good results can be obtained in any case.

The alkaline earth metal oxide preferably employs an organic carbonate compound as a material to be cured. Examples of the organic carbonate compound include an olefin carbonate, a water-soluble carbonate of an amine having 1 to 6 carbon atoms, and a nitrogen carbonate compound.

Examples of the above-mentioned carbonic olefin include ethylene carbonate and propylene carbonate. Examples of the water-soluble carbonate of an amine having 1 to 6 carbon atoms include methylamine, dimethylamine, diethylamine, trimethylamine, triethylamine, tetramethylammonium hydroxide, methanolamine, ethanolamine,
There are carbonates such as propylamine, butylamine, amylamine and hexylamine, and olefin carbonates such as ethylene carbonate and propylene carbonate are preferable from the viewpoint of strength development. Examples of the nitrogen carbonate compound include carbamic acid and urea.

The mixing ratio of the alkaline earth metal oxide and the organic carbonate compound is set to 100%.
1 to 80 parts by weight of the organic carbonate compound relative to parts by weight,
Preferably, 10 to 50 parts by weight is good. This is because when the amount of the organic carbonate compound is less than 5 parts by weight or more than 80 parts by weight, mechanical properties such as bending strength and compressive strength of the molded inorganic cured composition decrease.

In the above inorganic cured composition, a compounding agent may be appropriately compounded within a range that does not affect the surface gloss.
This compounding agent includes reinforcing fiber, aggregate, water reducing agent, defoamer,
There are foaming agents, other chemical admixtures for cement, pigments, setting retarders for setting the pot life during molding and setting accelerators.

Examples of the reinforcing fibers include glass fibers, metal fibers, synthetic resin fibers, carbon fibers, and organic fibers such as cellulose.

As the above-mentioned aggregate, silica sand, cold water stone, silica stone powder,
Granite, andesite, crushed natural stones such as marble, common aggregates such as blast furnace slag, shirasu balloons, fired products such as expanded clay and expanded shale, fired stones of vermiculite, black stone and perlite, glass There are lightweight aggregates such as balloons, which can be used alone or in combination depending on the purpose.

Examples of the setting retarder include oxycarboxylic acid and salts thereof, EDTA (ethylene / diamine / tetraacetic acid)
And its salts, polyhydric alcohols and their salts, and silicon fluoride.

As the above-mentioned setting accelerator, Na ₂ CO ₃ , K
_{2 C0 3, NaCl, KCl,} CaCl 2, sodium aluminate, there is alum, it may be used in combination of these two or more.

The above-mentioned inorganic cured composition contains impurities (eg, Fe ₂ O ₃ , Al ₂ O ₃ , Si
O ₂ , TiO ₂ , Na ₂ O, K ₂ O, etc. and the above-mentioned carbonates such as MgCO ₃ , CaCO ₃ , SrCO ₃ and hydroxide M
g (OH) ₂ , Ca (OH) _2, etc.) in an amount of 1 to 30% by weight.

The procedure for kneading the inorganic cured composition can be appropriately changed. The mixer is not particularly limited, and may be a kneader type, a Hensiel type, an omni type, or a conventionally known general mixer. Can be used.

As the molding method, a molding method using the above-mentioned mold can be appropriately selected and used, and specific examples include cast molding, press molding, extrusion molding, spray molding, centrifugal molding, and trowel coating. In order to promote the development of strength, after curing, heating and humidifying curing such as steam curing and autoclave curing can be performed. By carrying out appropriate heating and humidifying curing, practical strength can be obtained one day after casting.

According to the present invention, in a method for molding an inorganic cured composition in which the inorganic cured composition is put into a mold and cured and molded, the surface roughness Rz (10-point average roughness (JI
SB 0601)) is 0 <Rz ≦ 0.50 μm, and the linear expansion coefficient β of the mold is 0 <β <2.5 × 10 ⁻⁵ K ⁻¹ , whereby an inorganic cured material having a high and uniform surface gloss is obtained. A composition molding can be molded.

[0025]

EXAMPLES Examples and comparative examples according to the present invention will be described below in detail with reference to Table 1. The inorganic cured composition used in each of Examples and Comparative Examples was 2 parts by weight of magnesium oxide (manufactured by Nippon Kaisui K.K.), an organic carbonate compound, and a water reducing agent (FT-3S manufactured by Denka Grace Co., Ltd.) (Table 1). (Not shown) and water. The organic carbonate compound used in Examples 1 to 6 and Comparative Examples 1 to 6 was ethylene carbonate (manufactured by Toa Gosei Chemical Industry Co., Ltd.).
In Example 7, propylene carbonate (special grade reagent, manufactured by Kanto Chemical Co., Ltd.) was used. In addition, the numerical value in the inorganic hardening composition of Table 1 is a weight part.

[0026]

[Table 1]

The material of the mold, the surface roughness, and the coefficient of linear expansion in each of Examples and Comparative Examples are as shown in Table 1, and the surface roughness is 10-point average roughness (JIS B 0601).
This is the value when the cutoff value is 2.50 mm and the length is 12.5 mm. The coefficient of linear expansion of stainless steel, iron plate and aluminum is based on the heat transfer engineering data (Japan Society of Mechanical Engineers), and the coefficient of linear expansion of borosilicate glass is based on the revised 3rd edition Chemical Handbook Basic Edition (edited by The Chemical Society of Japan). The coefficient of linear expansion of other resins was measured according to JIS K 7197. In Table 1, ">7.0" in the coefficient of linear expansion means that the value was larger than 7.0 and measurement was impossible.

The gloss measurement in Table 1 is based on JIS K
7105 (60-degree specular gloss)
The “maximum value” is literally the maximum value of the measurement result, and the “range” is the difference between the maximum value and the minimum value.

Next, a procedure for molding a molded article of the inorganic cured composition to be measured in the present example and comparative examples will be described.

In each of the test examples and comparative examples, the magnesium oxide as the alkaline earth metal oxide having the compounding ratio shown in Table 1 was mixed with an omni-mixer (OM-10E, manufactured by Chiyoda Giken Kogyo Co., Ltd.).
(10 liters in internal volume), kneading and feeding ethylene carbonate or propylene carbonate as an organic carbonate compound and water, kneading them under reduced pressure for 5 minutes, and further, a mold having an inner size of 300 × 300 × 10 mm. After air was exhausted with a vibrator and covered with a smooth iron plate and excess kneaded material was discharged, steam curing was performed in a steam curing tank at 70 ° C for 24 hours at room temperature for 1 day. For 7 days.

When comparing the examples and the comparative examples, regardless of the material of the transfer type, the smaller the value of the surface roughness, the higher the maximum value of the gloss, and the smaller the value of the coefficient of linear expansion, the higher the gloss. The range was small. In addition, as shown in Examples 1, 2, and 3, and Comparative Examples 1, 2, and 3, the results obtained were not related to the material of the inorganic cured composition.

[0032]

According to the present invention, there is provided an inorganic cured composition molding method in which an inorganic cured composition is placed in a mold and cured and molded, wherein the surface roughness Rz (10-point average roughness (J
ISB 0601)) is 0 <Rz ≦ 0.50 μm and the linear expansion coefficient β of the mold is 0 <β <2.5 × 10 ⁻⁵ K ⁻¹ , whereby a high and uniform A molded article of the inorganic cured composition having a surface gloss can be obtained.

Continuing from the front page (72) Inventor Mitsuaki Saito 2-3-1-1, Kamakura-shi, Kanagawa Toyo Kagaku Co., Ltd. (72) Inventor Shunichi Mikami 2-3-1-1, Kamakura-shi, Kanagawa Toyo Kagaku (72) Inventor Kinnoyuki Oka 2-13-1, Dai, Kamakura-shi, Kanagawa Prefecture Toyo Chemical Co., Ltd.

Claims (1)

[Claims] 1. An inorganic curing composition is placed in a mold and cured.
In the method for molding an inorganic cured composition to be molded, the surface roughness Rz of the mold (10-point average roughness (JIS B060)
1)) is 0 <Rz ≦ 0.50 μm, and the linear expansion coefficient β of the mold is 0 <β <2.5 × 10 ⁻⁵ K ⁻¹ .