JPH06157130A - Inorganic binder and sintered block using inorganic binder and production therefor - Google Patents

Abstract

PURPOSE:To provide an inorganic binder having a self-curing property and presenting a stone-like surface in a half-fused state by firing at a relatively lower temp. and to provide a sintered block excellent in a design property, appearance not impaired by chipping, etc., high slipping resistant value in a wet state, superior in the dimensional stability, and excellent in water absorptive property, while it keeps high strength, by using the inorganic binder as a raw material for the surface layer. CONSTITUTION:The inorganic binder being formed by mixing 8-46wt.% alumina cement, 5-27wt.% a boric compound expressed in terms of B2O3, 5-70wt.% siliceous material, 5-30wt.% blast furnace slag (but the sum of the above described siliceous material and the blast furnace slag is <=70wt.%), and 0.5-5wt.% alkali metal compound expressed in terms of R2O (R is Na or /K), is used as raw material for the surface layer, and it is an integrally molded product together with the raw material for base layer and the sintered block in which only the surface layer is a half-fused sintered state, is produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic binder, a sintered block for architectural and civil engineering, which uses the inorganic binder and is excellent in design, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, architecture with excellent aesthetics and design,
As civil engineering materials, there are ceramic blocks, slabs, granite blocks, etc., which are widely used for urban environment maintenance such as sidewalks, roads, and parks.

These ceramic sinters are fine powders of natural stone such as granite, granite and marble, or feldspar, porcelain stone,
And clay as a main raw material, and using alumina cement or Portland cement as a binder, hydrate and harden them in a mold or press-mold at a high pressure of 1000 to 3000 kgf / cm ² , and thereafter at 1000 to 1600 ° C. It is manufactured by sintering. These manufacturing methods are described in JP-B-4-9747, JP-A-3-261649, and JP-A-3-2.
15350 and Japanese Patent Laid-Open No. 4-12076.

Further, as an inorganic binder having a hydraulic property at room temperature and a heat resistance, there is a castable binder disclosed in JP-A-4-65347. In this castable binder, the strength of a concrete product using ordinary Portland cement is remarkably lowered by the dehydration reaction of the hydrate at a temperature of 600 ° C or higher, whereas in the temperature range of 800 to 1000 ° C, Its strength is rather improved. Alumina cement 15 to 60% by weight, blast furnace slag 25 to 75% by weight, siliceous material 5 to 15% by weight, and boron compound at 0.1 in terms of B ₂ O _3. ˜5% by weight, and an inorganic binder made by mixing 1.5 to 4% by weight of an alkali metal compound in terms of R ₂ O (R is Na and / or K).

[0005] Furthermore, alumina cement, which is a refractory material, is used as a binder, and a glaze is welded to the heat-resistant block surface containing a heat-resistant aggregate made of an inorganic oxide as a main component to give a beautiful appearance. As the block for use, there is, for example, a molded article for building materials of Japanese Patent Application Laid-Open No. 48-99962.

[0006]

However, first of all, in the above-mentioned ceramic sinter such as a ceramic block, a palletized stone plate, and a granite block, the handling property, the dimensional stability and the strength at the time of manufacturing are ensured. Therefore, it is necessary to make a compact compact, and the structure of the obtained sintered compact must be dense. Therefore, when it is used as a road block, it has high strength but is difficult to handle because of its large specific gravity. However, it has drawbacks such as poor drainage due to small water absorption, and high safety as a walking and running material due to low slip resistance.

Further, in the castable binder disclosed in JP-A-4-65347, in order to obtain a stone-like surface in a semi-molten state, a molded body using the binder as a raw material is 1200 ° C. It is necessary to fire at a high temperature above, the sintered body obtained by such high temperature firing, the surface becomes a semi-molten stone-like surface, but discolored yellow, impairing the surface aesthetics, The firing temperature range where stable strength and dimensions are obtained and the firing temperature range for obtaining the above-mentioned semi-molten stone-like surface are inconsistent, and the production of blocks having stable strength and dimensions and having a stone-like surface Was not available in this alone.

Further, in the method of improving the aesthetic appearance by subjecting the hardened body of heat-resistant cement to the enamel treatment, the enamel for pottery used for diaper finishing is not suitable for pottery and tiles. Although it exhibits good adhesiveness, it cannot be expected to have sufficient adhesiveness in the case of cement materials that have completely different properties from pottery and tiles, and the difference in shrinkage between the caustic agent and cement hardening layer due to firing As a result, peeling or warping of the wax layer may occur after firing, and peeling, warping or the like of these wax layers significantly impairs the appearance of the surface.

The present invention has been made in view of the various drawbacks of the above-mentioned prior art, and its purpose is to have self-hardening moldability and fire at a relatively low temperature of about 900 to 1200 ° C. By providing an inorganic binder exhibiting a semi-molten stone-like surface by using the inorganic binder as a raw material for the surface layer, the design is good, and the semi-molten portion becomes relatively thick and chipped, etc. Accordingly, it is an object of the present invention to provide a sintered block which does not impair the aesthetic appearance, has a high slip resistance value in a wet state, has excellent dimensional stability, and has high water absorption while maintaining high strength, and a method for producing the same.

[0010]

In order to achieve the above object, the inventors of the present invention firstly describe 8 to 46% by weight of alumina cement, 5 to 27% by weight of a boron compound in terms of B ₂ O ₃ , and a siliceous substance. 5 to 70% by weight, blast furnace slag 5 to 30% by weight
(However, the sum of the siliceous material and the blast furnace slag is 7
0% by weight or less) and an alkali metal compound in R ₂ O (R
Devised an inorganic binder (claim 1) formed by mixing 0.5 to 5% by weight in terms of Na and / or K).

A sintered block in which the above-mentioned inorganic binder used as the binding material for the surface layer and the raw material for the base layer are integrally molded, and only the surface layer is in a semi-molten sintered state (claim) Item 2) was invented.

As a method for producing the above-mentioned sintered block, the raw material for the surface layer and the raw material for the base layer are integrally molded by pressure or vibration pressure, and the integrally molded product is 900 to 1200.
A method for manufacturing a sintered block that is fired at ° C (claim 4) was devised.

Here, as the binding raw material for the base layer,
Alumina cement 15-60% by weight, blast furnace slag 25-
75% by weight, 5 to 15% by weight of siliceous material, 0.1 to 5% by weight of boron compound in terms of B ₂ O ₃ , and R ₂ O (R is Na and / or K) in terms of alkali metal compound. It is more preferable to use an inorganic binder (claims 3 and 5) obtained by mixing 1.5 to 4% by weight. This is because the inorganic binder of this compounding ratio has a small dimensional stability because of its small coefficient of thermal expansion in the firing process, and can be integrally sintered with the surface layer composed of the inorganic binder according to the present invention. 1200 ° C
This is because it is possible to obtain sufficient strength at the firing temperature.

The features of the above-described inorganic binder according to the present invention, the sintered block using the inorganic binder, and the method for producing the same are that the shrinkage rate due to drying and firing is low, the dimension is stable, and the surface is wet. Has a large slip resistance value, has sufficient water absorption while maintaining sufficient strength, has a lower firing temperature than a general ceramic sinter, and has a smaller bulk specific gravity.

The above characteristics can be derived because the inventors of the present invention have created a novel inorganic binder, and a sintered block using the inorganic binder as a surface layer, and a method for producing the sintered block. .

The novel inorganic binder is composed of alumina cement, boron compound, siliceous material, blast furnace slag, and alkali metal compound as described above. Those configurations will be described in detail below.

As the alumina cement, any of commercially available refractory materials and construction materials may be used. The proportion of this alumina cement in the inorganic binder is in the range of 8 to 46% by weight. This is because when the amount is less than 8% by weight, the strength after molding is low, the rapid hardening characteristic of alumina cement does not appear, and it cannot be immediately removed as a block, and when it exceeds 46% by weight, 1200 ° This is because a stone-like surface in a semi-molten state is not exhibited at a firing temperature lower than C.

Examples of the boron compound include boron oxide, boric acid, colemanite, borosilicate glass, etc., and the ratio of these boron compounds in the inorganic binder is 5 to 27 in terms of B ₂ O _3. % By weight. This is 900 when the amount of boron compound is less than 5% by weight.
This is because the inorganic binder does not melt at a firing temperature of up to 1200 ° C and does not become a good semi-molten state.
If an amount exceeding 7% by weight is mixed, it is difficult to obtain dimensional stability, and the slip resistance value of the surface is remarkably reduced, impairing the function as a walking and running material, and also the chemical stability is reduced. Is.

As the alkali metal compound, Na is used.
Or carbonates, hydrogencarbonates, nitrates, silicates of K
Examples thereof include hydrogen compounds. Further, both boron and an alkali metal element may be contained. Examples of these compounds include borax, 5-borax, and borosilicate alkali glass. Percentage of inorganic binder of these alkali metal compounds, 0 in R ₂ O conversion.
5 to 5% by weight. If the proportion of the alkali metal compound is less than 0.5% by weight, it is difficult to obtain the handling property after molding, and if it exceeds 5% by weight, the dimensional stability is lowered and the slip resistance value of the surface is significantly impaired. This is because the chemical stability also decreases.

Furthermore, as the siliceous material, silica fume, the grinding of natural silica stone, etc., SiO of the substance ₂
The content should be 80% or more. The ratio of the siliceous material in the inorganic binder is 5 to 70% by weight.

Further, the blast furnace slag is obtained as a by-product in a normal blast furnace operation, and its constituent components are S
It is iO ₂ , Al ₂ O ₃ , CaO and MgO, and is obtained by pulverizing amorphous quenching slag. The ratio of the blast furnace slag in the inorganic binder is 5 to 30% by weight. If the respective proportions of the siliceous material and the blast furnace slag are less than 5% by weight, the viscosity of the melt becomes low, and the dimensional stability as a block cannot be obtained. The siliceous material and blast furnace slag are 70% by weight and 30% by weight, respectively.
If it exceeds 50% by weight, or if the total amount of both exceeds 70% by weight, the inorganic binder does not melt and a semi-molten surface cannot be obtained.

The above boron compound, siliceous substance and alkali metal compound act as a flux and a sintering aid to melt the binder at a firing temperature of about 1000 ° C. By causing liquid-phase sintering at the interface with and, the sintering strength of the sintered body is developed. The fineness of these powders is preferably fine.

Further, in order to further improve the designability when the inorganic binder is used as a surface layer bonding material, about 2 to 5% by weight of the inorganic binder with the above composition,
You may add the commercially available inorganic pigment for baking.

Next, a detailed description will be given of a sintered block using the above-mentioned inorganic binder according to the present invention as a bonding raw material for the surface layer, and a manufacturing method thereof.

Here, as the binding raw material constituting the base layer of the sintered block, as described above, the alumina cement 15 is used.
˜60 wt%, blast furnace slag 25˜75 wt%, siliceous material 5˜15 wt%, boron compound 0.1˜5 wt% in terms of B ₂ O ₃ , and alkali metal compound R ₂ O.
An inorganic binder formed by mixing 1.5 to 4 wt% in terms of (R is Na and / or K) is desirable.

In each kneading of the inorganic binding material according to the present invention as a binding raw material for the surface layer and the inorganic binding material as a binding raw material for the base layer, the mixing ratio of the inorganic binding material, the aggregate and the water is particularly limited. However, as a guide,
In both cases, inorganic binder: aggregate: water = 1: 1 to 3: 0.1
It may be mixed in the range of 5-0.6.

Here, as the aggregate, one having a melting point higher than that of the inorganic binder such as chamotte, foundry sand, blast furnace slag ore, brick waste and sewage sludge molten slag is used, and the particle size is 5 mm or less. Is desirable. Further, as a reinforcing material for the base layer, fibers such as steel, glass, alumina, and carbon may be added in an amount of about 2% based on the volume of the molded body. Further, if necessary, the high-performance water reducing agent may be added in an amount of 0.5 to 2% based on the total amount of the inorganic binders.

The molding is preferably carried out by pressure molding with a pressure of 50 to 500 kgf / cm ² , vibration molding, or vibration pressure molding in which both are combined to obtain an integrally molded product. These molding methods allow immediate demolding,
This is because handling properties are added immediately after molding and the strength of the sintered body is increased.

Even if the obtained integrally molded product is cured, it does not affect its performance. In addition, this integrally molded product is
It is desirable to dry at about 00 to 300 ° C for about 2 hours. This is because this increases the strength of the sintered body.

The firing is performed in the temperature range of 900 to 1200 ° C. for about 3 to 6 hours. This is because when the firing temperature is lower than 900 ° C, the surface is not in a semi-molten state and the strength of the sintered body is low. Further, when the firing temperature is increased, the bending strength is increased, but the surface resistance becomes smooth, so that the slip resistance value becomes low, and at a firing temperature of more than 1200 ° C, this appears remarkably, and the present inventors aimed at This is because the slip resistance value of 50 or more is not satisfied. Further, at a firing temperature of more than 1200 ° C, the surface layer is densified, so that the water absorption rate is lowered and the stone quality cannot be maintained in appearance.

The sintered body thus obtained may be slowly cooled by natural cooling.

The block may be manufactured by the conventional method before the firing.

The ratio of the surface layer to the base layer of the sintered block is not particularly limited, but a volume ratio of surface layer: base layer = 1: 2 to 8 is preferable.

As described above, the inorganic binder according to the present invention, the sintered block using the inorganic binder and the method for producing the same have a low shrinkage factor due to drying and firing, dimensional stability, and a wet state. Provides a sintered block that has a large slip resistance value on the surface, absorbs water while maintaining sufficient strength, has a lower firing temperature than general ceramic sinter, and has a low bulk specific gravity of the sinter. it can.

Here, the semi-molten state in the present invention means that the inorganic binder in the surface layer is homogeneously melted while maintaining its shape even by firing, and is sintered through the liquid phase at the interface with the aggregate. It means that you are doing. The term “sintered block” as used in the present invention means a block whose surface is in a semi-molten sintered state by firing at about 900 to 1200 ° C.

[0036]

EXAMPLES Examples of the present invention will be given below together with comparative examples.
The present invention will be described in detail.

Manufacture of Inorganic Binder (a) Materials Used Alumina Cement: “Alumina Cement No. 1” manufactured by Nippon Cement Co., Ltd. Al ₂ O ₃ : 53.2 wt%, CaO: 37.5 wt% Plain specific surface area 4900cm ² / g borax ─── UNITED STATES
Product made by BORAX & CHEMICAL, purity 99.5
100% silica fume ─── Efako Ltd. "Efakoshirika" SiO _2: 95.5wt% plain specific surface area 3500 cm ² / g powder silica ─── Chichibu Mining Co., Ltd., plain specific surface area 3500 cm ² / g sodium carbonate ─ ── Tokuyama Soda Co., Ltd. “Light ash” Blast furnace slag ── Daiichi Cement Co., Ltd. “Celament” SiO ₂ : 34.3 wt%, Al ₂ O ₃ : 12.2 wt
% CaO: 41.9 wt%, MgO: 0.62 wt% Plain specific surface area 3600 cm ² / g Pigment for firing ─── Nihon Glass Co., Ltd. “Y-89”
0 ”(b) Mixing method The above-mentioned materials to be used in various ratios shown in Table 1 (Examples 1 to 1
6 is the composition of the inorganic binder according to the present invention, Comparative Examples 1 to 4
Is a composition deviating from the composition ratio of the inorganic binder according to the present invention. Conventional product A of Comparative Example 5 is Portland cement 1
0 parts by weight, 40 parts by weight of kaolin, 30 parts by weight of feldspar, 20 parts by weight of silica, the conventional product B of Comparative Example 6 was blended with 20 parts by weight of Portland cement and 80 parts by weight of feldspar) Mix for about 5 minutes using a mixer.

[0038]

[Table 1]

Sintering Method and Evaluation Method of Inorganic Binder (a) Sintering Method Water is added to and mixed with the obtained inorganic binders having various compounding ratios, and the mixture is molded at a temperature of 200 ° C. before firing at 200 ° C. After drying for an hour, the temperature was raised at a rate of 200 ° C./hr, the temperature was maintained at the predetermined firing temperature shown in Table 1 for about 4 hours, and the material was gradually cooled in the furnace by spontaneous cooling. (B) Evaluation method The produced sintered blocks were evaluated by the following evaluation methods. a) Surface property (determination of semi-molten state) The state of the surface of the sintered block was visually observed and evaluated. ◯: The inorganic binder on the surface is completely homogeneously melted and liquid-phase sintered with the aggregate. X: The inorganic binder on the surface does not melt uniformly, and liquid phase sintering with the aggregate is not complete. b) Measurement of water absorption rate It was measured and evaluated by a performance test according to JIS R 2205. c) Measurement of sliding resistance value The sliding resistance value was measured and evaluated by a portable sliding resistor according to ASTM E 303-69. d) Measurement of wear resistance A wear resistance after 60 minutes was measured and evaluated by a performance test according to the wear resistance test of ASTM C779.

Examples 1 to 6 in Table 2 show physical properties (surface properties, absorptivity, slip resistance and wear resistance) of the sintered blocks obtained from the inorganic binder according to the present invention. Further, in Comparative Examples 1 to 4, the physical properties of the sintered blocks obtained from the compounds having a composition deviating from the compounding ratio of the inorganic binder according to the present invention, and in Comparative Examples 5 and 6 are described the physical properties of the conventional product. .

[0041]

[Table 2]

Production of Sintered Block of Two Layers (a) Material Used a) Same as (a) for surface layer. b) For base layer Borosilicate glass ─── Ibara Kosan Co., Ltd., grain size: #
20-60 mesh chamotte ───Mino Ceramic Co., Ltd. particle size 2.
5 mm or less High-performance water reducing agent ─── “Mighty 1” manufactured by Kao Corporation
00 ”(b) Manufacturing method a) Mixing Various ratios of the above-mentioned used materials shown in Table 3 (Examples 1 to 1)
6 is the composition of the inorganic binder according to the present invention, Comparative Examples 1-2
Is a composition deviating from the composition ratio of the inorganic binder according to the present invention. Conventional product A of Comparative Example 3 is Portland cement 1
0 parts by weight, 40 parts by weight of kaolin, 30 parts by weight of feldspar, 20 parts by weight of silica stone, the conventional product B of Comparative Example 4 was blended with 20 parts by weight of Portland cement, 80 parts by weight of feldspar) The mixture was thoroughly mixed with a mixer to produce an inorganic binder for the surface layer and an inorganic binder for the base layer. b) Kneading The respective ratios of the inorganic binder for the surface layer or the base layer: aggregate (chamotte): water were constant at 1: 2: 0.25. These were sufficiently kneaded by an omni mixer to produce mortar for the surface layer and the mortar for the base layer, respectively. c) Molding and demolding In a metal mold (length: 200 mm, width: 100 mm, height: 150 mm), mortar for base layer and mortar for surface layer are placed in this order so that the height is 7 cm: 1 cm, and 5
After press-molding at 0 kgf / cm ² for about 1 minute, it was immediately demolded. d) Drying and firing Put the integrally molded block that has been molded and demolded into an electric furnace, and
After heating to 200 ° C. for 2 hours and drying at 200 ° C. for 2 hours, this is heated at 200 ° C./hr, and the results are shown in Table 3.
After holding at the firing temperature shown in 4 hours for 4 hours, it was naturally cooled in the furnace.

[0043]

[Table 3]

Evaluation Method of Two-Layer Sintered Block The obtained two-layer sintered block was evaluated by the following evaluation method. a) Specific gravity measurement The outer dimensions (length, width, height) of the sintered block were measured with a caliper, and the weight was weighed and divided by the volume to calculate and evaluate. b) Measurement of dimensional accuracy The outer dimensions of the sintered blocks were measured with a caliper, and the variations between the blocks were calculated and evaluated. c) Bending strength test A performance test was performed according to the block bending test method of the Interlocking Block Association. In the bending strength test, the span is 160 mm, and the load is 8 minutes per minute at the center of the span.
~10kgf / cm ² addition is performed, the flexural strength was calculated by the following equation. σ = 24P / bd
² Here, σ is bending strength (kgf / cm ² ), P is maximum load (kgf), b is block width (cm), and d is block thickness (cm).

Examples 1 to 6 in Table 4 show the respective physical properties (specific gravity, dimensional accuracy and bending strength) of the two-layer sintered block using the inorganic binder according to the present invention as the surface layer. Further, in Comparative Examples 1 and 2, each physical property of a two-layer sintered block using a compound having a composition deviating from the compounding ratio of the inorganic binder according to the present invention as a surface layer, and in Comparative Examples 3 and 4, each physical property of a conventional product. Are also described together.

[0046]

[Table 4]

[0047]

As described above, the novel inorganic binder according to the present invention and the sintered block using the inorganic binder as the surface layer can provide the following effects. It has high slip resistance on the surface and is a material for sidewalks and roads with high safety in walking and running. While having sufficient strength as a sintered body, high water absorption can be added to the surface. While having sufficient strength, the specific gravity is small, which can reduce the labor of the worker in the construction work. Since it has self-hardening moldability, it can be molded into complicated shapes. Since a semi-molten sinter is obtained by firing at a relatively low temperature of 900 to 1200 ° C., a product having a stone pattern on the surface and excellent in designability can be obtained with lower energy than before.

Further, according to the method for producing a fired block of the present invention, the above fired block can be easily produced.

Further, the raw materials for the inorganic binder according to the present invention are readily available, and the conventional manufacturing process of the sintered block can be used. Therefore, it is possible to immediately manufacture and carry out the manufacturing process. Technology.

Claims (5)

[Claims] 1. Alumina cement 8 to 46% by weight, boron compound in terms of B ₂ O ₃ 5 to 27% by weight, siliceous material 5 to 70% by weight, blast furnace slag 5 to 30% by weight (however,
The total amount of the siliceous material and the blast furnace slag is 70% by weight.
The following), and R ₂ O (R is Na
And / or K) in an amount of 0.5 to 5% by weight, which is mixed, and an inorganic binder. 2. The binding raw material for the surface layer is the inorganic binding material according to claim 1, which is an integrally molded product with the raw material for the base layer, and only the surface layer is in a semi-molten sintered state. A sintered block characterized by: 3. The binding material for the base layer comprises 15 to 60% by weight of alumina cement, 25 to 75% by weight of blast furnace slag,
5 to 15% by weight of siliceous material, boron compound as B ₂ O ₃
0.1 to 5% by weight and R of alkali metal compound
_The sintered block according to claim 2, which is an inorganic binder formed by mixing 1.5 to 4% by weight in terms of ₂ O (R is Na and / or K). 4. The above-mentioned claim 1 as a binding raw material for a surface layer.
The inorganic binder described above is integrally molded with the raw material for the base layer by pressure or vibration pressure, and the integrally molded product is 900 to 1
A method for producing a sintered block, which comprises producing a sintered block in which only the surface layer is in a semi-molten sintered state by firing at 200 ° C. 5. The binding material for the base layer comprises 15 to 60% by weight of alumina cement, 25 to 75% by weight of blast furnace slag,
5 to 15% by weight of siliceous material, boron compound as B ₂ O ₃
0.1 to 5% by weight and R of alkali metal compound
_The method for producing a sintered block according to claim 4, wherein the inorganic binder is a mixture of 1.5 to 4% by weight in terms of ₂ O (R is Na and / or K).