JP3253403B2 - Inorganic composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a raw material for forming an inorganic molded article having excellent incombustibility, strength and durability, which is useful as a building member such as an inner or outer wall of a house or a building, a flooring material, a tile, etc. The present invention relates to an inorganic composition suitably used.

[0002]

2. Description of the Related Art Some proposals have been made on inorganic compositions which are cured by heat in the presence of an alkali. For example, as described in JP-A-4-59648, inorganic solid components such as ash of a dust collector and fly ash generated during production of an aqueous solution of an alkali metal silicate and metakaolin, corundum or mullite, and fillers and organic materials. It has been proposed to produce an inorganic molded article useful as a building material by mixing an admixture such as bentonite.
As described in Japanese Patent Publication No. 38, it has been proposed that fly ash is mixed with an aqueous solution of an alkali metal silicate and then cured by heating to obtain an inorganic molded article.

[0003]

However, when this kind of inorganic composition is cured to form an inorganic molded article, and when metakaolin is used, a large amount of alkali is required to obtain a kneaded material having a moldable viscosity. The strength and durability of the resulting inorganic molded body are low because a metal-containing salt aqueous solution is required, and when fly ash is used, fly ash has a low curing time due to low reactivity, and the resulting inorganic molded body There are problems that the strength and durability of the body are low and the appearance is poor.

Further, in the case of this type of inorganic molded body, the reaction in the molding process is a dehydration condensation reaction mainly using an aqueous solution of an alkali metal silicate, so that volume shrinkage occurs. As a result, cracks occur in the obtained inorganic molded body, and the strength is low and unstable,
Further, even when cracks do not occur, there is a problem that the water resistance and the like are reduced due to residual stress in the inorganic molded body.

The present invention solves the above-mentioned conventional problems, and increases the reactivity with an alkali metal hydroxide solution or an alkali metal silicate aqueous solution by using a specific fly ash. The purpose of the present invention is to provide an inorganic composition capable of obtaining a cured inorganic material having excellent nonflammability, strength and durability by preventing volume shrinkage of the composition.

[0006]

According to the present invention, 100 parts by weight of an inorganic powder obtained by injecting molten fly ash or kaolin into a gas and quenching the same is used.
10 to 300 parts by weight of the above alkali metal hydroxide aqueous solution or alkali metal silicate aqueous solution and a particle size of 40 to 20
It is an inorganic composition comprising 100 to 300 parts by weight of 0 μm silica sand.

In the present invention, fly ash is J
Refers to those specified in IS A 6201, and has a chemical composition of 45 to 75% by weight of SiO ₂ and Al ₂ O ₃ 15
~ 35% by weight as a main component, Fe ₂ O ₃ , Mg
Those containing O, CaO and the like as auxiliary components are preferably used.

In the present invention, kaolin is one of kaolinite, dickite, nacrite, and hylosite.
A kind or a kaolin clay mineral composed of two or more kinds, as a chemical component, 35 to 70% by weight of SiO ₂ , Al ₂ O ₃ 1
0 to 45% by weight as a main component, Fe ₂ O ₃ , M
Those containing gO, CaO, and the like as auxiliary components are preferably used.

In the present invention, the inorganic powder is obtained by heating and melting fly ash or kaolin and spheroidizing it by surface tension and then rapidly cooling the powder into a gas. As one of the means, a spraying technique applied to a ceramic coating is applied. The spraying technique is preferably such that the material powder is melted at a temperature of 2000 to 16000 ° C. and sprayed at a speed of 30 to 800 m / sec. A welding method or the like is possible. Fly ash or kaolin is injected into room temperature air or the like and quenched to obtain the inorganic powder of the present invention.

In the present invention, as the aqueous alkali metal hydroxide solution, one represented by the general formula MOH (M represents Li, K, Na or a mixture thereof) can be used, and its concentration is 10% or more. Should be present, and 10 to 50% is preferable. When the concentration is less than 10%, the reactivity with the inorganic powder is low.

In the present invention, the aqueous solution of an alkali metal silicate has a general formula M ₂ O.nSiO ₂ (M is Li,
K, Na or a mixture thereof, and n represents 0 to 5). Its aqueous solution concentration is 1
It must be 0% or more. When the concentration is less than 10%, the reactivity with the inorganic powder is low. If n exceeds 5, the aqueous solution of the alkali metal silicate tends to gel and the viscosity rises sharply, so that mixing with the inorganic powder tends to be difficult.

The amount of the aqueous alkali metal hydroxide solution or aqueous alkali metal silicate solution must be 10 to 300 parts by weight based on 100 parts by weight of the inorganic powder of the present invention. If the added amount is less than 10 parts by weight, it becomes difficult to knead with the inorganic powder, while if it exceeds 300 parts by weight, the mechanical strength of the obtained inorganic molded article is reduced.

In the present invention, 100 to 30 parts by weight of silica sand having a particle size of 40 to 200 μm is added to 100 parts by weight of the inorganic powder.
0 parts by weight are added. When the particle size is less than 40 μm, or when the addition amount of the particles having a particle size of 40 to 200 μm is less than 100 parts by weight, the dehydration condensation reaction of fly ash or kaolin with an aqueous alkali metal hydroxide solution or an aqueous alkali metal silicate solution Volume shrinkage due to
The strength reduction of the obtained inorganic molded body by the water resistance test becomes large, and conversely, it exceeds 200 μm or the particle size is 40 to 2 μm.
When the addition amount of the thing of 00 μm exceeds 300 parts by weight, kneading becomes difficult, and furthermore, the mechanical strength of the obtained inorganic molded article is reduced, and the strength reduction by the water resistance test is increased.

The curable inorganic composition of the present invention may contain an inorganic filler other than the above, if necessary. Examples of the inorganic filler include fly ash, alumina, talc, mica, rock powder, basalt, feldspar, clay,
Various minerals such as bauxite and fiber materials can be used. These inorganic fillers are appropriately selected according to the use of the inorganic molded article, and may be used alone or in combination. The amount of the inorganic filler added is 10
The amount is preferably 300 parts by weight or less with respect to 0 parts by weight,
More preferably, the amount is from 00 to 200 parts by weight. When the addition amount exceeds 300 parts by weight, the mechanical strength of the obtained inorganic molded article tends to decrease.

An organic foam or an inorganic foam may be added to the inorganic composition of the present invention, if necessary, to reduce the weight of the material. Examples of the organic foam include a granular foam of a synthetic resin such as polyvinyl chloride, phenol resin, urea resin, polystyrene, polyurethane, and polyethylene.

Examples of the inorganic foam include a particulate balloon such as a glass balloon, a shirasu balloon, a fly ash balloon, a silica balloon, pearlite, a hill stone, and a particulate silica foam. These foams may be used alone or in combination.

The specific gravity of these foams is preferably from 0.01 to 1, more preferably from 0.03 to 0.7. When the specific gravity is less than 0.01, the mechanical strength of the obtained inorganic molded article tends to decrease. On the contrary, when it exceeds 1, the effect of reducing the weight of the obtained inorganic molded article is obtained. There is no tendency.

The amount of these foams to be added is as follows.
It is preferably 200 parts by weight or less based on 00 parts by weight. When the addition amount exceeds 200 parts by weight, the mechanical strength of the obtained inorganic molded article tends to decrease.

A reinforcing fiber may be added to the curable inorganic composition of the present invention, if necessary. Any reinforcing fiber can be used in accordance with the performance to be imparted to the obtained inorganic molded article, and examples thereof include synthetic fibers made of materials such as vinylon, polyamide, polyester, polypropylene, carbon, aramid, acrylic, and rayon, and glass fibers. ,
Inorganic fibers made of materials such as potassium titanate and steel can be used.

The reinforcing fibers preferably have a fiber diameter of 1 to 500 μm and a fiber length of 1 to 15 mm. The thickness of the reinforcing fiber is
If it is too thin, it reagglomerates at the time of mixing, fiber balls are easily formed by entanglement, and the strength of the obtained inorganic molded article tends to be not further improved.If it is too thick or too short, the reinforcing effect such as improvement in tensile strength is small. If the length is too long, the dispersibility and orientation of the reinforcing fibers tend to decrease.

The amount of the reinforcing fiber added is preferably 10 parts by weight or less based on 100 parts by weight of the inorganic powder. Addition amount is 1
If it exceeds 0 parts by weight, the dispersibility of the reinforcing fibers tends to decrease.

As a method of forming an inorganic molded article from the inorganic composition of the present invention, the inorganic powder of the present invention, an aqueous alkali metal hydroxide solution or an aqueous alkali metal silicate solution, and if necessary, an inorganic filler A method in which a mixture obtained by kneading an organic or inorganic foam and a reinforcing fiber is used as a raw material and molded by a conventionally known method such as a casting method, a pressing method, or an extrusion molding method can be adopted. The curable inorganic molded article may be cured at room temperature,
It is preferable to heat and cure at a temperature of 00 ° C.

The present invention 2 is an inorganic composition comprising the inorganic composition of the present invention and 1 to 600 parts by weight, preferably 30 to 500 parts by weight of silica powder having a particle size of 0.01 to 30 μm.

If the particle size of the silica powder is less than 0.01, the specific surface area of the silica powder is large, and the amount of the aqueous alkali metal hydroxide solution or aqueous alkali metal silicate solution required for kneading is increased. The mechanical strength and durability of the obtained inorganic molded article are reduced, and conversely, when it exceeds 30 μm, or when the amount of addition of particles having a particle size of 0.01 to 30 μm is 1
If the amount is less than 600 parts by weight,
The effect of densely filling with silica sand cannot be obtained, and the mechanical strength and durability of the obtained inorganic molded article decrease.

Further, as a method for forming an inorganic molded article from the inorganic composition of the present invention 2, the same method as that of the present invention 1 can be employed.

The inorganic composition of the present invention is obtained by injecting molten fly ash or kaolin into a gas and quenching it, and mixing 100 parts by weight of an inorganic powder obtained with an alkali metal hydroxide having an aqueous solution concentration of 10% or more. 10 to 300 parts by weight of an aqueous solution or an aqueous solution of an alkali metal silicate, and a particle size of 40 to 200 μm
100-300 parts by weight of silica sand, the reactivity between the inorganic powder and the alkali metal hydroxide solution or the alkali metal silicate aqueous solution is high, and the inorganic powder and the alkali metal hydroxide aqueous solution or the alkali metal Silica sand sufficiently absorbs the volumetric shrinkage caused by the dehydration condensation reaction with the silicate aqueous solution, so that it is possible to obtain an inorganic cured body having excellent nonflammability, strength and durability.

The inorganic composition of the present invention 2 is composed of the inorganic composition of the present invention and silica powder 1 to 6 having a particle size of 0.01 to 30 μm.
By the amount of 00 parts by weight, the volume shrinkage due to the dehydration condensation reaction between the inorganic powder and the aqueous alkali metal hydroxide solution or the aqueous alkali metal silicate solution is sufficiently absorbed by the silica sand and the silica powder in a densely packed state. , A cured inorganic material excellent in nonflammability, strength and durability.

[0027]

【Example】

Preparation of inorganic powder Inorganic powder A Fly ash (manufactured by Kanden Kako Co., Ltd., chemical composition SiO ₂ 5
2.46 wt%, Al ₂ O ₃ 24.05 wt%, average particle size 20 μm, specific gravity area 1.8 m ² / g, JISA 62
After melting at 3000 ° C., the powder was atomized into the air at a speed of 80 m / sec and rapidly cooled to recover the inorganic powder A.
The obtained inorganic powder A had an average particle size of 5 μm and a specific surface area of 9.5 m ² / g, and showed no crystalline peak by X-ray diffraction analysis, and was substantially a completely amorphous substance. .

Inorganic Powder B Kaolin (Tsuchiya Kaolin Industries, Chemical Composition SiO_Two4
5.70% by weight, Al _TwoO_Three38.27% by weight, average grain
8.5m diameter^Two/ G, specific surface area 5.6m^Two/ G) is 300
After dissolving at 0 ° C, spray it into the atmosphere at a speed of 80 m / sec.
After quenching, the inorganic powder B was recovered. The obtained inorganic powder
B has an average particle size of 4.3 μm and a specific surface area of 64 m^Two/ G
No crystalline peak was confirmed by X-ray diffraction analysis.
It was a substantially completely amorphous body.

Method for Classifying Silica Sand Silica sand is classified into 40 to 105 μm using a classification sieve according to JIS.
m, 210 to 590 μm, and 420 to 840 μm.

Examples 1-8, 11-18, Comparative Examples 1-1
9 Predetermined amount of inorganic powder, silica sand classified to each particle size, silica stone powder (manufactured by Sumitomo Cement Co., particle size distribution 1-2 shown in Tables 1-4)
0 μm), vinylon fiber (thickness: 1.8 denier, length: 6)
mm), a predetermined concentration of an aqueous alkali solution or an aqueous alkali metal silicate solution was mixed for 5 minutes by a mixer. The mixture was poured into a mold having a width of 150 mm, a length of 150 mm, and a thickness of 10 mm, and was cured in an oven at a temperature shown in Tables 1 to 4 for a predetermined time to obtain an inorganic molded body.

The obtained inorganic molded body is cut to a width of 15 mm.
A test piece having a thickness of 0 mm, a length of 50 mm, and a thickness of 10 mm was prepared, and the cured state, bending strength, and hot water test were evaluated. The results are shown in Tables 1 to 4.

The evaluation method is as follows. The appearance was evaluated by visual observation of the cured state . Flexural Strength After the test piece was dried for 5 hours after curing and left in an air-dried state for 24 hours, the flexural strength was measured according to the method of JIS A1408. Hot water test The test piece was left in hot water of 98 ° C. or higher for 8 hours, and the presence or absence of cracks and cracks was checked.

Examples 9, 10, 19 and 20 A predetermined amount of inorganic powder, silica sand classified to each particle size, and silica stone powder (manufactured by Sumitomo Cement Co., Ltd., particle size distributions 1 to 2) shown in Tables 1 to 4
0 μm), vinylon fiber (thickness: 1.8 denier, length: 6)
mm), a predetermined concentration of an aqueous alkali solution or an aqueous alkali metal silicate solution was mixed for 5 minutes by a mixer.

The mixture was supplied to a vibration press molding machine (manufactured by Asahi Engineering Co., Ltd., trade name “SA-50”) in which the mold was heated to 110 ° C., and the molding pressure was 60 kg / cm.
^2. Press molding was performed while applying vibration at a frequency of 1000 Hz and an amplitude of 10 μm, and a simultaneous effect was obtained. About the obtained inorganic molded object, evaluation of the cured state, bending strength, and hot water test was performed in the same manner as in Example 1. The results are shown in Tables 1 to 4.

[0035]

[Table 1]

[0036]

[Table 2]

[0037]

[Table 3]

[0038]

[Table 4]

Comparative Examples 17 to 19 Untreated fly ash (manufactured by Kanden Kako Co., Ltd.) shown in Table 5
Chemical composition 52.46% by weight of SiO ₂ , Al ₂ O ₃ 38.
2% by weight, average particle size 8.5 m ² / g, specific surface area 5.6 m
² / g), metakaolin (Tsuchiyakaorinkogyo Co., chemical composition SiO52.2 wt%, Al ₂ O ₃ 44.3 wt%, average particle diameter 1.4 m ² / g, a specific surface area of 12m ² /
g), silica sand, silica stone powder (manufactured by Sumitomo Cement Co., particle size distribution 1 to 20 μm) classified to 40 to 105 μm, and an aqueous alkali solution or an aqueous alkali metal silicate solution of a predetermined concentration were mixed by a mixer for 5 minutes.

The mixture was treated in the same manner as in Example 1 to obtain an inorganic molded article. About the obtained inorganic molded object, evaluation of the hardening state, the bending strength, and the hot water test was performed like Example 1. FIG. The results are shown in Table 5.

[0041]

[Table 5]

[0042]

According to the first aspect of the present invention, as described above, it is possible to obtain an inorganic cured product excellent in nonflammability, strength and durability.

Since the second aspect of the present invention is configured as described above, it is possible to further obtain an inorganic cured body having excellent nonflammability, strength and durability.

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁷ Identification code FI C04B 14:06 C04B 14:06 Z 18:08) 18:08) (56) References JP-A-6-199517 (JP, A JP-A-6-211557 (JP, A) JP-A-3-109242 (JP, A) JP-A-4-6138 (JP, A) JP-A-4-59648 (JP, A) JP-A-4-1992 55350 (JP, A) JP-A-50-108310 (JP, A) JP-A-3-126652 (JP, A) JP-A-3-275543 (JP, A) JP-A-4-42843 (JP, A) JP-A-4-285043 (JP, A) International Publication No. 92/7803 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C04B 28/00 C04B 28/26 C04B 18/08 C04B 18/10 C04B 14/06 C04B 22/06 C04B 28/02 C04B 20/00-20/12

Claims (2)

(57) [Claims] 1. A method in which molten fly ash or kaolin is injected into a gas and quenched to obtain 100 parts by weight of an inorganic powder, and an aqueous solution of an alkali metal hydroxide or an alkali metal silicate having an aqueous solution concentration of 10% or more. Aqueous solution 10-30
0 parts by weight, and silica sand 100 to 30 having a particle size of 40 to 200 μm.
An inorganic composition comprising 0 parts by weight. 2. The inorganic composition according to claim 1, which has a particle size of 0.0
An inorganic composition comprising 1 to 600 parts by weight of 1 to 30 μm silica powder.