JPH05262579A - Glazed cement mortar product and its production - Google Patents

Abstract

PURPOSE:To provide a glazed product excellent in physicochemical characteristics, based on inexpensive cement mortar. CONSTITUTION:The objective cement mortar product with the surface layer of a cement mortar cured form laminated with a flat, lowtemperature glaze layer. This product can be obtained by coating a cement mortar cured form with a low-temperature glaze followed by baking at low temperatures (pref. 100-500 deg.C) and leaving the product to stand cool. Thence, the product is sprayed with or immersed in water and cured to obtain the objective glazed cement mortar product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel cement mortar product used for civil engineering, construction, etc. and a method for producing the same, and more particularly to a glazed product based on cement mortar having excellent physical and chemical properties and its production. It relates to a manufacturing method.

[0002]

2. Description of the Related Art Mortar or concrete using ordinary cement is an excellent structural material and has a very high compressive strength, but it has a low tensile strength, bending strength, corrosion resistance, etc. Is inferior. Further, the structural material has a defect that it cracks even at room temperature, and when exposed to a high temperature, it is damaged or explodes due to release of free water contained therein and part of bound water. Therefore, for example, even if a cement mortar cured product of the cured product is applied with a glaze and then the product is baked, an excellent glaze-free product without defects cannot be obtained.

That is, the cement mortar cured product of the cured product contains free water, which is released by heating during baking of the glaze. When the cement mortar cured product is heated, the cement hydrate therein decomposes from about 260 ° C. and begins to release bound water. Furthermore, calcium hydroxide also decomposes at about 500 ° C. and begins to release water. Further, in the vicinity of 800 ° C., the expansion of aggregate and the expansion of CaO increase, and the decomposition of CaCO ₃ starts. Due to the steaming of the water thus discharged and the expansion of the aggregate and the like, cracks or explosions are caused in the cement mortar molded body, or a concave portion of the steam discharge hole trace is formed on the glaze surface.

Therefore, general glazed products are made of ceramics that are stable to high-temperature treatment, which are usually highly hard and have excellent heat resistance and corrosion resistance, and are made of silica stone, clay and feldspar.
It is manufactured by applying glaze to the base material of the component system and baking it at a temperature of about 1000 ° C. or higher.

As described above, ceramic-based glazed products have been put on the market, but (a) the selected three-component compound materials and the high energy required for firing at about 1000 ° C. or higher are required. It will be very expensive, (b)
The product usually has a modulus of elasticity of 1.5 to 2 times that of concrete, but it is brittle like glass and has a local strain particularly due to high temperature firing, so that a large-scale product that can be used as a product is manufactured. There are problems such as being difficult.

[0006]

[Means for Solving the Problems] As a result of intensive studies in view of the above problems, the present inventors have solved the problems of the prior art, have excellent physical and chemical properties, and have a low cost. We have developed a glazed product based on cement mortar that can be manufactured in.

That is, the present invention provides (1) a glazed cement mortar product characterized in that a smooth low-temperature glaze layer is laminated on the surface of a cured cement mortar cured product.
And (2) A glaze cement mortar product characterized by applying a low temperature glaze to the surface of a cured cement mortar cured product, firing at low temperature, allowing to cool, and then subjecting the same cooled product to watering and curing. Is a manufacturing method.

Next, various components according to the present invention will be described. As the cement constituting the cement mortar, Portland cement (for example, ordinary Portland cement, white Portland cement), alumina cement, blast furnace cement and the like are used. Further, as the fine aggregate constituting the cement mortar, silica sand, refractory fine aggregate, granulated blast furnace slag fine aggregate, perlite, mesalite, inorganic fine aggregates such as shirasu balloon can be used alone or as a mixture. However, the particle size of these fine aggregates is usually 5 mm or less. Particularly, as the refractory fine aggregate, chamotte, ceramics (cerven), anti-fire stone, and granulated blast furnace slag are suitable. Such refractory fine aggregates are not easily attacked by alkali such as free calcium hydroxide generated during the hydration reaction of cement, and therefore do not cause alkaline aggregate reaction and have high mechanical strength. Therefore, it is possible to guarantee the stabilization of the quality and the increase in strength of the cured product. Further, cement products are generally vulnerable to high temperatures and easily disintegrate when heated to a high temperature, which serves to prevent this.
Further, it is also preferable to add ultrafine powder such as granulated blast furnace slag or silica as a pozzolanic substance.

The water / cement ratio of the cement mortar is theoretical value, that is, it is preferable to keep it within a minimum range of 22 to 28% as water necessary for forming calcium hydroxide. Requires the addition of organic admixtures

In the present invention, it is also preferable to add an inorganic reinforcing agent to the cement mortar, so that the impact-cured strength of the resulting cured cured product is improved. The inorganic reinforcing agent to be used is preferably short fiber glass fiber having a length of 4 to 20 mm, asbestos, Wallacenite (CaSiO ₃ ), sepiolite (magnesium silicate) and the like.

When an organic admixture such as a water reducing agent is used, the cement mortar base material is 1
Since the temperature is raised to 20 ° C. to 500 ° C., it is preferable that the amount of organic substances such as methyl cellulose as a water reducing agent or a binder is extremely small. Generally, a base material containing a few% of such an organic substance is melted and decomposed to generate a liquid or gas due to a temperature rise during glaze, which makes proper glaze difficult.

As the low temperature glaze (in the present invention, a glaze which forms a glassy glaze layer at a relatively low temperature, usually about 100 ° C. to about 600 ° C. is referred to as “low temperature glaze”), a glass layer at a relatively low temperature is used. A glaze or a lead-containing low-temperature glaze to be formed, a water-soluble silanol-based one, and a metal alcoholate-based one can be used. Silicon-based inorganic sols, phosphoric acid-based inorganic sols, alkali borosilicate-based glasses and hydrated glasses are also preferably used. The glazes are applied onto the cement mortar compact by spraying or coating, then dried and fired at a low temperature.

Generally, the higher the melting point of a glaze, the more excellent the chemical properties such as corrosion resistance and chemical resistance, but the firing temperature of cement mortar, which is the base material, is limited, so that silica, feldspar, borax and soda ash are used. 120 with a small amount of fluoride
A so-called frit which is melted at 0 to 1300 ° C and rapidly cooled cannot be used. Therefore, the glaze used in the present invention has no choice but to use a low temperature glaze. The low-temperature glaze is a good quality that does not cause cracks, pinholes, etc., and it is particularly preferable to use a low-temperature glaze having a difference in thermal expansion coefficient between the glaze and the cement mortar substrate as small as possible.

The composition and the like of the low temperature glaze used in the present invention are not particularly limited, but the glaze already developed by the present inventor (JP-A-1-115482) can be preferably used. The glaze is based on 100 parts by weight of ceramic fine powder,
120 to 60 parts by weight of the alkali silicate is added and kneaded, and one or more of zinc oxide, zinc hydroxide, zinc phosphate, iron oxide and iron hydroxide fine powder is added to 12 to 12 parts by weight.
After adding 3 parts by weight, 1 to 2 parts of one or two powders of aluminum, zinc and iron is added to 6 to 1 parts by weight, and further 130 to 50 parts by weight of ice mass or water is added and sufficiently kneaded at an appropriate temperature, Viscosity obtained by adding 8 to 0.5 parts by weight of a minute amount of calcium aluminum silicate fine powder having a fineness of about 3000 cm ² / g and one or more kinds of boron compounds or barium compounds and kneading again. The low temperature glaze, which is a liquid material, is applied to the surface of the cement mortar substrate, and then low temperature firing is performed. The glaze layer thus obtained has high strength and strong adhesive strength and fire resistance, and is preferably used in the present invention.

The hydration / curing performed to accelerate the hardening reaction of the cement mortar, which is the base material of the glazed product, reduces and supplies a part of water such as crystal water lost by the heating during the glaze baking to the substrate, It plays a role of completing the hydration reaction, and can be carried out by curing in water or under supersaturated water vapor pressure. As the curing method, it is preferable to perform low temperature curing at 10 ° C. to 80 ° C. in a saturated steam atmosphere. 150 ° C to 20 under steam pressure if necessary
It is also possible to perform autoclave curing at 0 ° C.

Molding of the cement mortar cured product can be carried out by using known molding means such as vacuum extrusion molding, pressure injection molding into a mold, or press molding.

[0017]

EXAMPLES The present invention will be specifically described below with reference to examples. First, various cement mortar specimens for obtaining a plate-shaped cement mortar compact were manufactured with the components shown in Table 1. The details of some blended raw materials in Table 1 are as follows. * Used 2 mm unders from Seto for silica fine aggregate * Used 0.3 mm under for GUNTECH B (trade name) from NKK Co., Ltd. as fine aggregate blast furnace granulated slag * For ultrafine blast furnace granulated slag, "Finest" by NKK
(Product name) 12,000 Blaine is used * The fiber reinforcing agent is glass fiber, heat resistant glass fiber "Mineron M801" (Product name) 13 mm of Asahi Glass Co., Ltd. and US
A Combined use of wollastonite from Connecticut, Utah * The high-performance water reducing agent is “Chupol HP-1” of Takemoto Yushi
Use 1 "(product name)

Next, each of the test pieces shown in Table 1 was pressure-molded to obtain a plate-shaped molded body (50 mm × 50 mm × 25 mm), which was then glazed and cured by the temperature cycle shown in FIG.
Here, a method for producing the low temperature glaze used in this example will be described below. A sinter whose main component is aluminum silicate and has many fine pores is crushed to about 0.5 to 300 μm. The particles are about 300-37 μm, about 37-2 μm,
The particle size distribution is distributed in four stages of particle size distribution of about 2 to 0.5 μm and about 0.5 μm or less.
500 g of aluminum silicate sinter and grind is prepared by mixing in a weight ratio of 4: 1/9. 450 g of sodium silicate (corresponding to 2.17 in terms of molar ratio) was added to and mixed with the aluminum silicate sinter and crushed product, and then 40 g of zinc oxide powder crushed to 200 mesh or less was added to sufficiently Knead. Then, 7.5 g of aluminum powder crushed to 200 mesh or less is added, and subsequently 400 g of ice powder is added and sufficiently kneaded by a crushing and kneading machine. Then, 10 g of calcium aluminum silicate powder pulverized to about 2500 cm ² / g (specific surface area) or more and about 25 ml of water are added, followed by stirring and kneading. Further, about 10 g of boric acid is added and the mixture is kneaded again.

The low-temperature glaze produced as described above was glazed on the cement mortar compact and heat-treated according to the heating curve shown in FIG. After that, steam curing treatment was performed under the same conditions as shown in FIG.

FIG. 1 shows a series of process time and temperature conditions from the application of the above-mentioned low temperature glaze on a cement mortar molded product to the steam curing to obtain a glazed cement mortar product. Next, the processes of to in FIG. 1 will be described. In the cement mortar compact, the above low temperature glaze is applied (glazing), and 5 minutes in 20 minutes.
Heating up from 0 ℃ to 200 ℃, at 200 ℃
Hold for 20 minutes at 200 ℃ by natural cooling in
To room temperature. The glazed product thus obtained is then subjected to steam curing for 4 hours while raising the temperature from room temperature to 70 ° C., the steam curing is continued at 70 ° C. for 24 hours, and finally allowed to cool naturally to room temperature. Return to complete a series of processing steps.

The cement mortar molded body that has been cured and cured as described above is glazed and fired in (1), and then steam cured in (1),
The required binding water and the like, which are partially lost during the firing of the glaze, are reduced and imparted to the cement mortar compact, and the hydration reaction is completed.

The physical properties of each glazed cement mortar molded product obtained by carrying out the treatment process shown in FIG. 1 are as shown in Table 2. From the results shown in Table 2, each cement mortar tile product has a fire resistance of up to 500 ° C., a high bending strength, a high tensile strength and a high compression strength, which are the same as those of ordinary cement mortar products, and the surface of which is glass. Since it is covered with a high-quality glaze, the water absorption rate and water permeability from the surface are extremely small,
And you can see that the appearance is also beautiful.

In contrast to this, No. A cement mortar molded product obtained by using a composition of 3 composition and performing no steam curing treatment after the glaze heat treatment has a fire resistance of 50.
0 ° C., bending strength 150 kg / cm ² , tensile strength 75
kg / cm ² and compressive strength are 750 kg / cm ² , water absorption is 0.10%, water permeability is 0.08 g, appearance is white and transparent, fire resistance, bending strength, tensile strength and compression The physical property values such as strength were deteriorated to 90% or less of those obtained by the steam curing treatment.

[0024]

As described in detail above, according to the present invention,
Many excellent effects as described below can be obtained. ． It is possible to provide a novel glazed cement mortar product in which an excellent glaze layer is firmly provided on the cured product of the cement mortar cured product. ． We can provide excellent glazed tile products that have the original physical and chemical properties of cement mortar. ． Large, non-strained, glazed cement mortar products can be easily manufactured. ． The manufacturing cost of the product is about 1/10 of that of the conventional ceramic tile because the base is made of cement mortar.
Low cost. ． Since the glaze and cement mortar are similar in composition and their thermal expansion coefficients are similar, the bond between them is strong. ． Since the glazed cement mortar product and the concrete have similar thermal expansion coefficients, when the product of the present invention is adhered to a concrete wall surface or the like, there is no risk of dropping due to the peeling.

[Brief description of drawings]

FIG. 1 is a process diagram showing a series of steps of heating a cement mortar compact, glazeing it, and then performing steam curing treatment to obtain a glazed cement mortar product.

Claims (6)

[Claims] 1. A glazed cement mortar product, characterized in that a smooth low-temperature glaze layer is laminated on the surface layer of a cured cement mortar cured product. 2. A glazed cement mortar characterized by applying a low temperature glaze to the surface of a cured cement mortar cured product, firing at low temperature, allowing to cool, and then subjecting the same cooled product to watering and curing. Product manufacturing method. 3. The method for producing a glazed cement mortar product according to claim 2, wherein the low temperature firing is performed at 100 to 500 ° C. 4. The method for producing a glazed cement mortar product according to claim 2 or 3, wherein the cement mortar contains an inorganic reinforcing agent such as asbestos, glass fiber, wollastonite, or sepiolite. 5. The molding of a cured cement mortar cured product is performed by a vacuum extrusion molding method, a pressure injection molding method into a mold, or a press molding method.
5. The method for producing a glazed cement mortar product according to any one of 4 to 4. 6. The low temperature glaze is ceramic fine powder 100.
120 to 60 parts by weight of alkali silicate is added to parts by weight and kneaded, and one or more of zinc oxide, zinc hydroxide, zinc phosphate, iron oxide, and iron hydroxide fine powder are added to the mixture and kneaded. ~ 3 parts by weight of aluminum, zinc,
After adding 6 to 1 parts by weight of one or two kinds of iron powder and further adding 130 to 50 parts by weight of ice mass or water and sufficiently kneading at a suitable temperature, a fineness of about 3000 cm ² / g is obtained. Calcium aluminum silicate fine powder and one or more of boron compound or barium compound 8 to 0.5
The method for producing a glazed cement mortar product according to any one of claims 2 to 5, which is a viscous liquid material obtained by adding parts by weight and kneading again.