JP4343617B2 - Lightweight inorganic board and method for producing the inorganic board - Google Patents

Description

  The present invention relates to a lightweight inorganic board used for building boards such as outer wall materials and interior materials, and a method for producing the inorganic board.

BACKGROUND OF THE INVENTION
An inorganic plate obtained by molding and firing ceramic powders such as silica and alumina into a plate shape is excellent in durability, and is frequently used as a building plate having a high-quality design with a sense of beauty and texture.
The inorganic plate is manufactured by adding a binder and water to a ceramic powder and kneading, forming the kneaded product into a plate shape by extrusion molding or casting, and firing the plate-shaped product, It has high hardness and poor machinability, and it is difficult to easily cut to a predetermined size on site. In the case of a large plate, the weight is large and labor is required for transportation and construction work, and when it is attached to a wall frame or the like, the weight load on the wall frame becomes large.

[Conventional technology]
Therefore, as means for solving the problems of the above-mentioned inorganic board, a material containing a combustible organic component such as a pulverized waste material of a wood cement board is added to an inorganic raw material, water is added and kneaded, and the kneaded product is extruded. An inorganic plate produced by molding into a plate shape and the like and firing the plate-like molded product is provided.
In the inorganic board, the organic components such as the wood reinforcing material contained in the wood cement board waste mixed with the inorganic raw material at the time of firing are burned down, and as a result of forming a porous structure, the weight becomes light, and the machinability (See, for example, Patent Documents 1, 2, and 3).

JP 2002-321966 A ([0014]) Japanese Patent Laying-Open No. 2003-206186 (Claim 1) JP-A-6-191964 (Claim 1)

  However, the lightweight inorganic plate is inferior in design because the surface becomes porous and exhibits a rough surface, and dust enters the concave portions on the surface, and dirt tends to adhere. Furthermore, it is difficult to give a clear uneven pattern to the surface by embossing. There is also a problem that the internal structure is easily deteriorated due to water absorption, and further the freeze-thaw resistance is deteriorated.

As a means for solving the above-mentioned conventional problems, the present invention provides an inorganic material having a three-layer structure in which an inorganic raw material layer containing a combustible organic component is arranged on the core layer, and an inorganic raw material layer containing no combustible organic component is arranged on the front and back layers. It is intended to provide a lightweight inorganic board in which the core layer is made porous by firing the green plate and burning the combustible organic component of the core layer.
As the combustible organic component, it is desirable to use a wood component contained in the wood cement board waste material, and it is desirable that the inorganic raw material includes a hydraulic inorganic material, a glassy material, and an aggregate. The organic layer content of the core layer is preferably 5 to 35% by mass.
Further, the specific gravity of the front and back layers is preferably 1.5 to 1.8, and the specific gravity of the core layer is preferably 0.8 to 1.3.
A desirable method for producing the lightweight inorganic board of the present invention is to spread an inorganic raw material for the front and back layers on the template, form a surface layer or a back layer mat, and spread an inorganic raw material for the core layer on the front layer or the back layer mat. The core layer mat is formed, the inorganic material for the front and back layers is spread on the core layer mat, the back layer or the surface layer mat is formed, and the mat having the three-layer structure thus obtained is pressed in the presence of moisture. It is a dry method or semi-dry method in which the cured and cured inorganic plate is fired.

[Action]
In the lightweight inorganic board of the present invention, since the core layer is porous, the core layer is light and excellent in machinability and workability, but the front and back layers are not porous but have a dense structure. A smooth and favorable appearance is obtained, and clear embossing is facilitated. In addition, the front and back layers prevent moisture from penetrating into the plate, so that the internal structure is hardly deteriorated and the plate is excellent in durability and freeze-thaw resistance. Further, in the core layer, when the wood cement board waste material is used together with the combustible organic component-containing material , the waste material can be effectively used.
If the inorganic board of the present invention is produced by a dry or semi-dry method, productivity is improved and mass production is facilitated, and there is no need to finely grind waste materials. In the case of extrusion molding, since the raw material kneaded product is extruded from the die, it is necessary to finely grind the waste material so that the die is not clogged. In addition, the moisture content of the mat to be formed is lower than that of extrusion molding, and further fired after compression biocure. The firing efficiency is much higher than that of the extruded product. Furthermore, when providing a concavo-convex pattern on the surface, a concavo-convex shade pattern is formed on the template surface, and the raw material is distributed thereon, so that a clear concavo-convex pattern can be given.

〔effect〕
The present invention provides a lightweight inorganic board that is lightweight, has high mechanical strength, is excellent in freeze-thaw resistance, has good workability, has a smooth surface, and is excellent in design.

The present invention is described in detail below.
[Wood cement board waste]
In the present invention, the wood cement board waste material used as a combustible organic component-containing material is a wood reinforcing material such as a piece of wood, wood fiber bundle, wood pulp, wood wool, wood powder, ordinary Portland cement, early strength cement, Using a raw material mixture mainly composed of cement such as alumina cement, blast furnace slag cement, fly ash cement, lime such as quick lime and slaked lime, or hydraulic inorganic material such as gypsum and magnesium carbonate, dry method, semi-dry method It is a waste material of wood cement board formed into a plate shape by the method, wet method, extrusion molding method, etc., but it is used to grind and recycle the scrap materials during the manufacturing process and these waste materials generated at the time of extension and reconstruction .
The wood cement board usually contains 10 to 30% by mass of the wood content.

  The wood cement board may further contain organic fibers such as polyester fiber, polyamide fiber, polyethylene fiber, polypropylene fiber and acrylic fiber, and flammable organic components such as expanded polystyrene beads, polyethylene beads and polypropylene beads. These combustible organic components are also burned out and contribute to the porous structure of the core layer together with the wood.

  The wood cement board waste is usually pulverized to a particle size of about 10 to 100 μm by an impact type pulverizer or a grinding type pulverizer, and used as a raw material of the present invention.

[Inorganic raw materials]
In the present invention, it is desirable to use a hydraulic inorganic material as the main inorganic material. Examples of the hydraulic inorganic material include ordinary portland cement, early-strength cement, alumina cement, blast furnace slag cement, fly ash cement, and other cements, limes such as quick lime and slaked lime, gypsum, and magnesium carbonate.
When the above-mentioned hydraulic inorganic material is used, the green plate can be cured before firing, a hardened green plate having a certain degree of strength and not easily damaged can be obtained, and workability, yield, and the like are improved.
Further, as an inorganic material, it is desirable to add a vitreous material that is melted by firing and becomes a binder. Examples of such a vitreous material include shirasu, fly ash, gangue stone, glass powder, pulverized plate glass, glass foam, slag, shirasu balloon, pearlite, and the like.

  Furthermore, in the present invention, an aggregate which is melted by firing and becomes a main element of the plate structure is added. Examples of the aggregate include clay minerals such as porcelain stones, feldspars, wax stones, kaolin, halosite, kibushi clay, glazed clay, sericite, chamotte, dolomite, quartz sand, quartzite, diatomaceous earth, glitter, There are siliceous materials such as minestone and silica fume.

  Furthermore, in the present invention, inorganic fibers may be added in order to improve the mat strength, product strength and the like. Examples of the inorganic fibers include mineral fibers such as wollastonite and sepiolite, metal fibers such as steel fibers and stainless fibers, glass fibers, and ceramic fibers such as mullite alumina fibers.

[Flammable organic components]
In the present invention, a combustible organic component may be used as a raw material for the core layer together with the wood cement board waste or instead of the wood cement board waste. Examples of such flammable organic components include wood chips, wood fiber bundles, wood pulp, wood wool, wood flour and other wood materials, polyester fibers, polyamide fibers, polyethylene fibers, polypropylene fibers, acrylic fibers and other organic fibers, foam There are synthetic resin components such as polystyrene beads, polyethylene beads, and polypropylene beads.

[Raw material mixture for front and back layers]
As the raw material for the front and back layers, the above-mentioned hydraulic inorganic material, glassy material, aggregate, and inorganic fiber are used, and no organic component is used.
In the raw material mixture for the front and back layers, usually 10 to 30% by mass of the hydraulic inorganic material, 10 to 30% by mass of the vitreous material, 35 to 45% by mass of the aggregate, and 15 to 25 when the inorganic fiber is used. The ratio is about mass%. When the aggregate is added in an amount exceeding 45% by mass, the specific gravity of the plate becomes high, and it is difficult to reduce the weight, and the workability also deteriorates. On the other hand, when the aggregate is added in an amount less than 35% by mass, the strength of the plate is lowered and the frost resistance is also deteriorated.

[Raw material mixture for core layer]
As the raw material for the core layer, in addition to the raw material for the front and back layers, the pulverized wood cement board waste material and / or the combustible organic component is used.
In the raw material mixture for the core layer, it is desirable that the amount of the pulverized wood cement board waste and / or the combustible organic component is about 5 to 35% by mass. When the amount of the combustible organic component is less than 5% by mass, the core layer is not sufficiently porous and the weight is not reduced. On the other hand, if the amount of the combustible organic component exceeds 35% by mass, the core layer becomes excessively porous, resulting in poor mechanical strength and frost resistance.

[Method for producing lightweight inorganic board]
As a method for producing the lightweight inorganic board of the present invention, a semi-dry method using a raw material mixture in which a predetermined amount (usually 5 to 20% by mass) of water is added is generally applied, but water is added to the raw material mixture. Alternatively, a dry method in which water is added immediately before or after compression curing biocure may be applied.
That is, in the production method of the present invention, the inorganic material for the front and back layers is spread on the template to form the surface layer or the back layer mat, and the inorganic material for the core layer is spread on the surface layer or the back layer mat. Form the core layer mat, spread the inorganic raw material for the front and back layers on the core layer mat, form the back layer or the surface layer mat, and press the resulting three-layer mat in the presence of moisture. Curing and curing are performed, and the resulting inorganic plate raw plate is fired to obtain the lightweight inorganic plate of the present invention.

In the above method, a predetermined uneven shade pattern may be formed on the template surface. In addition, the pressing is usually performed at a surface pressure of 5 to 8 MPa in a pressing device in which a template is further stacked on a formed three-layer structure mat. A predetermined uneven shade pattern may be formed on the surface.
Curing and curing is performed in the above-mentioned pressing state, and a condition of 6 to 10 hours is usually employed at a temperature of 45 to 65 ° C.
After curing and curing, it is depressurized and desirably dried in an absolutely dry state, and subjected to predetermined processing such as actual processing. Further, if desired, a glaze is applied to at least the surface of the raw inorganic plate. As the glaze used in the present invention, general glazes such as lead yu, frit yu, bristol yu, porcelain yu and the like are used. Thereafter, the raw inorganic plate is introduced into a firing furnace and fired. As firing conditions, conditions of 900 to 1100 ° C. and 10 to 20 minutes are usually employed.
The lightweight inorganic board thus produced usually has a thickness of 15 to 20 mm, a specific gravity of the front and back layers of 1.5 to 1.8, and a specific gravity of the core layer of about 0.8 to 1.3.

[Examples 1-5, Comparative Examples 1-5]
Spread the raw material mixture for the front and back layers shown in Table 1 on the template, spread the raw material mixture for the core layer thereon, and form a mat with a three-layer structure on which the raw material mixture for the front and back layers is further spread. The mat having the three-layer structure is subjected to press-curing biohardening for 8 hours under the conditions of a surface pressure of 5 MPa and a temperature of 50 ° C. in the presence of moisture. Three layers of Examples 1 to 5 and Comparative Examples 1 to 5 having a thickness of 18 mm were dried and introduced into a firing furnace having a glaze applied to the surface and fired at a temperature of 1000 ° C. for 10 minutes. A lightweight inorganic board sample was prepared.

  Referring to Table 1, in the case of the sample of Comparative Example 1 in which aggregate (chamotte) is contained in the raw material mixture of the front and back layers in an amount exceeding 45% by mass, the specific gravity of the front and back layers is increased (1.85). ), Workability deteriorates. Further, in the case of the sample of Comparative Example 2 in which the combustible organic component (polystyrene foam beads + wood chips) is contained in the core layer raw material mixture in an amount of less than 10 mass% (8 mass%), the specific gravity of the core layer Increases (1.35), and the workability deteriorates as in Comparative Example 1. Moreover, in the case of the sample of the comparative example 3 which added 20 mass% of ceramic fibers instead of the wollastonite in the raw material mixture for the front and back layers, the specific gravity of the front and back layers is low, the bending strength is lowered, and the frost resistance is deteriorated. Further, in the case of the sample of Comparative Example 4 in which the combustible organic component (polystyrene foam beads + wood chips) is contained in the core layer raw material mixture in an amount exceeding 35% by mass (40% by mass), the bending strength decreases. Freezing resistance has deteriorated. Furthermore, in the case of the sample of Comparative Example 5 using an inorganic hollow lightweight body (pearlite) in order to make the front and back layers porous, the weight reduction is realized, but the bending strength decreases, and the frost resistance deteriorates. In addition, the surface becomes rough and the appearance deteriorates.

  The inorganic board of the present invention is light and has good transportability, workability and workability, is excellent in mechanical properties and freeze-thaw resistance, and is excellent in design, so it is useful for exterior wall materials and interior materials. .

Claims (3)

A core layer arranged inorganic material layer comprising a hydraulic inorganic material and glass material and aggregate and combustible organic component comprises a hydraulic inorganic material and glass material and aggregate and inorganic fibers on the front and back layers, flammable the inorganic board raw plate of three-layer structure in which arranging inorganic material layer containing no organic component by firing, a lightweight inorganic board where the core layer on a porous by Shometsu combustible organic components of the core layer And
The vitreous material of the core layer is one of shirasu, fly ash, mine stone, glass powder, crushed plate glass, glass foam, slag, shirasu balloon, pearlite,
The aggregate of the core layer is made of ceramic stone, feldspar, wax stone, kaolin, halosite, kibushi clay, glazed clay, sericite, chamotte, dolomite and silica sand, quartzite, diatomaceous earth, glitter, minestone, silica fume Either
The glassy material of the front and back layers is either shirasu, fly ash, glass powder, crushed plate glass, or slag,
The aggregate of the front and back layers is one of ceramic stone, feldspar, wax stone, kaolin, halosite, kibushi clay, glazed clay, sericite, chamotte, dolomite, quartz sand, quartzite, diatomaceous earth, glitter, silica fume Yes,
The inorganic raw material layer of the core layer contains 5 to 35% by mass of a combustible organic component,
The inorganic raw material layers of the front and back layers include 35 to 45% by mass of aggregate and 15 to 25% by mass of inorganic fibers,
The core layer is porous, and the specific gravity of the core layer is 0.8 to 1.3,
The lightweight inorganic board, wherein the front and back layers are not porous but have a dense structure, and the specific gravity of the front and back layers is 1.5 to 1.8 . Inorganic material layer of the core layer are both flammable organic components were ground to a particle size 10~100μm of wood cement board waste material comprises a wood component, wood cement board waste milled with the combustible organic components Content is 5-35 mass%, The lightweight inorganic board of Claim 1 characterized by the above-mentioned. An inorganic raw material for the front and back layers is spread on the template to form a surface layer or a back layer mat, an inorganic raw material for the core layer is spread on the front layer or the back layer mat, and the core layer mat is formed. An inorganic raw material for front and back layers is spread on top to form a back layer or surface mat, and the three-layered mat thus obtained is pressed and cured in the presence of moisture. A method for producing a lightweight inorganic board for firing
The compression curing is performed at a surface pressure of 5-8 MPa and a temperature of 45-65 ° C. for 6-10 hours.
The method for producing a lightweight inorganic board according to claim 1 or 2 , wherein the firing is performed at a temperature of 900 to 1100C for 10 to 20 minutes .