JPS6037068B2 - Manufacturing method of inorganic cured body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an inorganic cured body used as a building material, particularly a noncombustible building material.

BACKGROUND ART Inorganic cured bodies used as building materials and the like have been manufactured in the following manner.

That is, calcium aluminate monosulfate hydrate (father a0, AI203, CaS04, n ratio 0
, n has a value of approximately 12, hereinafter referred to as "MSH"
A slurry mainly composed of gypsum, blast furnace slag, cement, and water is shaped into a predetermined shape, and then cured to react with MSH and gypsum with water to form calcium aluminate trisulfate hydrate (abbreviated as a○・A
I203.CaS04.n is ○, n takes a value of approximately 31 or 32 (hereinafter abbreviated as "TSH")), and blast furnace slag and cement were hydrated and hardened. The inorganic cured body produced in this manner has high impact strength and bending strength, and is excellent as a building material. However, this inorganic cured body shrinks and cracks when heated to high temperatures, which poses a problem as a nonflammable building material. Therefore, in order to solve such problems, it has been considered to add asbestos to a slurry whose main components are MSH, gypsum, blast furnace slag, cement, and water. However, asbestos is a specified chemical substance, and its use worsens the working environment and increases costs, so adding asbestos also poses problems. In view of these circumstances, the inventors conducted repeated research and found that they incorporated gypsum fibers into a slurry whose main components are MSH, gypsum, blast furnace slag, cement, and water, and used this to create an inorganic hardened material. When manufacturing
This invention was completed based on the discovery that an inorganic cured product that does not crack even when heated to high temperatures and has excellent impact resistance and bending strength can be obtained.

That is, this invention can be applied to MSH, gypsum, blast furnace slag,
The gist of this method is to add gypsum fibers to a slurry whose main components are cement and water, shape the slurry containing the gypsum fibers, and then cure and harden the slurry.

Next, this invention will be explained in detail.

In this invention, a slurry whose main components are MSH, gypsum, blast furnace slag, cement, and water is used.

Such a slurry can be prepared by a conventional method, that is, by mixing the above-mentioned raw materials for the slurry and, if necessary, adding additives such as pulp, reinforcing fibers such as glass fibers, and water reducing agents. Manufactured by. In this case, the state of the slurry does not matter. Therefore, it may be in a highly fluid state or in a pasty state. Also, MSH
, gypsum, blast furnace slag, cement, and water as the main components includes cases where the entire product is composed only of these raw materials. Further, among the raw materials for slurry, cement includes not only Boltland cement but also all types of cement. Furthermore, instead of using blast furnace slag and cement separately, blast furnace cement may be used instead. This invention allows such a slurry to contain gypsum fibers.

In order to include such gypsum fibers in the slurry, it can be done by adding and mixing the gypsum fibers to the slurry, or it can be added in advance to the slurry raw materials when mixing the slurry raw materials to form a slurry. This is done by in this case,
The content of gypsum fiber is based on the matrix formed by hydrating and hardening MSH, gypsum, blast furnace slag, and cement (this is a hydrated and hardened hydraulic binder, and does not include additives such as reinforcing fibers). 2-4% by weight (hereinafter abbreviated as "%")
It is preferable to select such that
The range is 20%. That is, the effect is greatest when the content of gypsum fiber is in the range of 2 to 40% of the matrix, and the most effective is in the range of 4 to 20%. In addition, when the hydraulic binder hardens by hydration and becomes a matrix, the weight increases by approximately 20%, so the amount of gypsum fiber used is adjusted in consideration of this at the time of raw material blending, and the amount of gypsum fiber is increased. The content can be adjusted to fall within the above range. In addition, the ratio of MSH and gypsum in the slurry is preferably selected so that the weight ratio of MSH/gypsum is 1/0.2 to 1/0.7, and the total content of blast furnace slag and cement is It is preferable to select the hydrated cured product so that it accounts for 2 to 70% of the matrix.

Moreover, it is preferable to select the matrix so that it occupies 65% or more of the inorganic cured product. In other words, the effect becomes greater even within these ranges. next,
The slurry containing the stone-tone fibers is dovetail-shaped into a predetermined shape by a normal shaping method, that is, by a paper-making method, a casting method, etc., and then subjected to, for example, moist heat curing (curing performed at high temperature and high humidity). After that, it is cured at room temperature for about one round to become a cured inorganic material.

Due to the action of the gypsum fibers, the inorganic hardened body obtained in this way does not crack due to shrinkage even when heated to high temperatures.
Moreover, it has excellent impact resistance and bending strength. In other words, "This inorganic hardened material does not crack even when heated to high temperatures, so it is particularly useful as a noncombustible building material. Furthermore, if the slurry containing gypsum fibers is shaped by the papermaking method, gypsum The effect of the effect of the fibers is to improve the surface condition of the shaped body (plate-like), thereby improving the surface condition of the resulting inorganic cured body.

Next, examples will be described together with comparative examples.

Examples 1 to 5 MSH 35 parts by weight (hereinafter abbreviated as "parts"), dihydrate gypsum 2
Sparse area, 25 parts of blast furnace cement, 5 parts of pulp, 2 parts of glass fiber
A slurry was prepared by adding water and mixing.

Next, gypsum fibers (manufactured by Onoda Cement Co., Ltd., type anhydrous gypsum) are added and mixed into this slurry in the amount shown in the table below, and this is sanded to make a green sheet (plate-shaped excipient). Ta. Next, this green sheet was pressed to adjust its thickness and specific gravity appropriately. Next, the green sheets that have been pressed are placed in a heating curing room and heated to a temperature of 70q.
o. Humid heat curing was performed under conditions of humidity 100% RH. next,
This was placed in a polyethylene bag and left for one round at room temperature for curing. Then, the cured product was dried at 4500° C. to a constant weight to obtain an inorganic cured board with a specific gravity of 1.0 and a thickness of 5.5. Comparative Example Addition of gypsum fiber was discontinued.

Other than that, inorganic cured plates of the same dimensions were obtained in the same manner as in Examples 1 to 5. Performance tests were conducted on the inorganic cured plates obtained in the above Examples and Comparative Examples.

The results are also shown in the table below. As is clear from the table,
It can be seen that all of the inorganic cured plates obtained in the examples have good flammability evaluation scores and are excellent as nonflammable materials, and are also excellent in bending strength and Charpy impact strength. In addition, according to the examples, it can be seen that the surface condition of the green sheet is improved, and thereby an inorganic cured plate with an excellent surface condition can be obtained. The tests in the table were conducted as follows.

{i- Combustibility test In the combustibility surface test based on JISAI 321, the size of cracks that occurred on the cured board after the test was visually evaluated on a 5-grade scale and an evaluation score was given.

The smaller and better the crack, the higher the score. {
ii} Bending test The bending strength was measured using a No. 4 test piece based on JISAI408.

'iii' Charpy impact test A Charpy impact test was conducted according to JIS K6911.

Rib Green sheet surface condition Judgment was made with the naked eye.

Claims (1)

[Claims] 1. A slurry containing calcium aluminate monosulfate hydrate, gypsum, blast furnace slag, cement, and water as main components contains gypsum fibers, and the slurry containing the gypsum fibers is shaped. A method for producing an inorganic cured product, which is then cured and cured. 2. A method for producing an inorganic hardened body according to claim 1, wherein the slurry containing gypsum fibers is shaped by papermaking. 3 The content of gypsum fiber is 2 to 2 for the matrix formed by hydration hardening of calcium aluminate monosulfate hydrate, gypsum, blast furnace slag, and cement.
The method for producing an inorganic cured body according to claim 1, wherein the content is selected to be 40% by weight.