JPS59203748A - Manufacture of alc - 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 method for producing ALC (high-temperature, high-pressure steam-cured lightweight cellular concrete), and more particularly, to a method for producing ALC with improved bending properties.

In recent years, ALC is rapidly becoming popular in various fields of construction due to its excellent lightness, fire resistance, strength characteristics, etc. However, the bending properties and brittleness of ALC itself are not sufficiently high, and therefore, there are some fields in which its use is prevented.

In addition to increasing the bending strength by incorporating fibers or reinforcing materials such as steel, the present inventors believe that the bending properties may be improved by modifying the calcium silicate hydrate that makes up the ALC body. As a result of many years of intensive research, we have discovered the present invention.

The present invention is a method for producing ALC, which is characterized in that calcium silicate hydrate prepared by a special method is present in the ALC raw material slurry. Calcium hydrate is obtained by curing a mixture of mainly siliceous raw materials and calcareous raw materials, which have been mixed in powder form in advance, in high-temperature, high-pressure steam while remaining in powder form. In the present invention, the product obtained by this special method will be simply referred to as a powdered curing agent hereinafter.

The raw materials for producing this powdered curing agent include silicic raw materials such as borax and sandstone powder, which are ALC raw materials, quicklime, slaked lime,
Any calcareous material such as cement can be used. For example, if sandstone powder and quicklime powder are
The mixture is mixed in powder form so that the ratio of ab/Sing is 0.05 to 1.0, and the powder mixture is cured with high temperature and high pressure steam, for example, 140 to 200 ° C.
Preferably, it is pulverized so that it can be uniformly dispersed in the ALC slurry, and then present in the ALC slurry.

Here, the ALC slurry refers to the commonly used ALC slurry.
Slurry is mainly composed of silica raw materials and calcareous raw materials.The main raw materials are silica powder and lime powder (cement in some cases), and the necessary amount of auxiliary raw materials such as foaming agents such as At powder. This is an ALC slurry made by adding water. When adding the powdered curing agent, it may be mixed with silica powder in advance, or it may be added directly to the slurry containing the main raw materials of silica powder and lime powder.
It is sufficient that a powdered curing agent is present in the slurry. The amount of the powdered curing agent added is 5% to 65% by weight, preferably 10% to 40% of the solid matter in the ALC raw material slurry, to achieve the effect of the present invention, that is, the effect of improving bending properties. Ru.

In addition, the ALC raw material slurry is powdered curing agent CaO/5
CaO/
By changing the ratio of 5t02, the final slurry CaO/8i02
The ratio of 0.3 to 1.0, more preferably 0.5 to 0.
It is okay to make it 8.

According to the present invention, the raw material slurry to which the powdered curing agent has been added is injected into a mold, and after reaching the hardness required for handling, it is cut into a desired shape with piano wire, etc., if necessary, and usually ALC. The product is made by curing in high-temperature, high-pressure steam, which is used in the manufacturing method.

It is unclear why the bending strength of the ALC obtained in this way is improved, but instead of using a powdered curing agent, water is added to a mixture mainly consisting of siliceous raw materials and calcareous raw materials to form a slurry. ALC'! Since the bending strength hardly improves even after i=manufacturing, it is recognized that this is a unique effect of the powder curing agent.

Examples are shown below in order to make the present invention clearer, but
As a calcareous raw material for powder curing, use of quicklime provides ALC with higher bending strength than that using slaked lime.

Example 1 100 parts by weight of silica powder and 10 parts by weight of quicklime were thoroughly mixed, the dry powder was cured in saturated steam at 180°C for 10 hours, and the resulting powder was crushed to form a mixture for ALC molding.
That is, 15 parts by weight was added to 100 parts by weight of a powder mixture of 55 parts by weight of silica powder, 35 parts by weight of cement, and 10 parts by weight of quicklime, and 65 parts by weight of water was added to form a slurry. In addition, it was poured into a mold, foamed, and semi-hardened. After semi-curing, send to autoclave and heat at 180℃
Curing was completed by steam curing for about 10 hours using saturated steam. The physical properties of this molded product were as follows.

Air dry specific gravity 0.5 Bending strength 20.0 Kg/lt/1 Compressive strength
41.0 kg/al.

Comparative Example 1 Instead of the powdered curing product of Example 1, 100 parts by weight of silica powder and 10 parts by weight of quicklime were thoroughly mixed, 55 parts by weight of water was added to form a slurry, and the mixture was heated with saturated steam at 180°C. The same treatment as in Example 1 was carried out using a powder obtained by crushing the cured material. The physical properties of this molded product were as follows.

Air dry specific gravity 0.5 Bending strength 20.0 K9/crA compressive strength
41.0 ~/d Comparative Example 1 Instead of the powdered curing product of Example 1, 55 parts by weight of water was added to a mixture of 100 parts by weight of silica powder and 10 parts by weight of quicklime to form a slurry. After curing with saturated steam at 180° C., the powder was crushed and treated in the same manner as in Example 1. The physical properties of this molded product were as follows.

Air dry specific gravity 0.5 Bending strength 10.9 K9/ld compressive strength
40.5 kg/ltl.

Comparative Example 2 The AL described in Example 1 was prepared without using the powder curing product of Example 1.
The molded product, which was treated with C molding mixture under the same conditions as in Example 1, had the following physical properties.

Air dry specific gravity 0.5 Bending strength 11.2 Kf/l:rl Compressive strength
40.0 Kg/i Example 2 100 parts by weight of silica powder and 12 parts by weight of slaked lime were thoroughly mixed, and the mixture was cured in dry powder form with saturated steam at 180°C. It was treated in the same manner as in Example 1. The physical properties of this molded product were as follows.

Air dry specific gravity 0.5 Bending strength 18.9 Kglad compressive strength 4
0. OKgltyA Example 3 The powder curing product of Example 1 was added to the ALC molding mixture in an amount of 20 parts by weight, and the same treatment as in Example was carried out. The physical properties of this molded product were as follows.

Air dry specific gravity 0.5 Bending strength 22. s Kg/cyst compressive strength
41, 5 K9/cI! Example 4 100 parts by weight of silica powder and 75 parts of quicklime were thoroughly mixed, and the dry powder was cured in saturated steam at 180°C, then crushed to form a powder, and ALC molded as in Example 1. It was added in an amount of 10 parts by weight to 100 parts by weight of the mixture, and treated under the same conditions as described in Example 1. The physical properties of the molded product obtained were as follows.

Air dry specific gravity 0.5 Bending strength 21. OKglcrl Compressive strength 40.8 Kq/crA Example 5 Ioo parts by weight of silica powder and 12 parts by weight of quicklime were thoroughly mixed, and the dry powder was cured in saturated steam at 160°C and then crushed to form a powder. , was added in an amount of 35 parts by weight to 100 parts by weight of the ALC molding mixture of Example 1, and treated under the conditions described in Example 1. The physical properties of the molded product obtained were as follows.

1- Air dry specific gravity 0.55 Bending strength 23.5 Kg/crA compressive strength
44.7 K9/dt Patent applicant Asahi Kasei Corporation-' --36

Claims (1)

[Claims] In the ALC manufacturing method, a mixture consisting mainly of silicic acid raw materials and calcareous raw materials, which has been mixed in powder form in advance, is heated in high-temperature, high-pressure steam while still in powder form. A manufacturing method for ALC characterized by the presence of a cured product