JP2931768B2 - Method for producing inorganic molded plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a porous structure inside, and is a lightweight and highly insulating inorganic material.
The present invention relates to a method for manufacturing a plate .

[0002]

2. Description of the Related Art Conventionally, a reinforcing material such as wood chips and pulp fibers is mixed with cement, and a raw material mixture obtained by further mixing foamable plastic beads is molded and heated to foam the foamable plastic beads in the raw material mixture. Further, by melting the plastic beads foam particles obtained by foaming the expandable plastic beads to form a large number of pores in the molded body, lightweight and heat insulating properties,
A method for producing a porous cement board having insulation properties such as soundproofing properties has been provided (JP-A-54-1).
No. 57125, JP-B-63-1276).

[0003]

However, in the above-mentioned conventional porous cement board, it is not possible to obtain a board material having a smooth surface and excellent cosmetic properties due to the presence of pores on the surface.
In addition, water permeability and moisture permeability are also large. Also, in the case of a conventional wood chip cement board using wood chips as a reinforcing material, there is almost no entanglement between the wood chips, so that the strength of the obtained product is sufficient unless the pressing force during molding is increased to increase the product density. However, in the case of a conventional pulp-containing cement board using pulp fibers as a reinforcing material, the density of the cement-pulp fiber mixture is increased and foaming of the expandable plastic beads is suppressed.

[0004]

Means for Solving the Problems The present invention is a means for solving the above-mentioned conventional problems, which is a dry manufacturing method with high production efficiency.
Cement 30 to 60 there is provided a manufacturing method and wherein the drying-type production method
Wt%, silicic acid containing material 30-60 wt%, perlite
0-15 wt%, flake and / or wood flour 5-25
% Of the mixture A with 30 to 45% by weight of water.
Spread in a mat on a template with an uneven pattern formed on it , and further
30 to 60% by weight of cement, 30 to 60% of silicic acid-containing substance
Wt% , perlite 0-15 wt%, wood fiber bundle 5-2
5% by weight, flakes 4 to 10% by weight, foamable thermoplastic
Plastic beads 0.5-5% by weight and water 30-4
Sprinkle the mixture B with 5% by weight in a mat shape from above,
Further spraying in a mat shape thereon said mixing compound A three-layer
Step 1 of forming a mat having a structure
Pressing heated Oh Step 2 above preliminary-cured material to pre-cured
Foaming thermoplastic plus by curing with autoclave
Step 3 of foaming and curing the tic beads
A method for producing an inorganic molded plate comprising the above steps 1, 2, 3
Is provided . Further, the wood fiber bundle is branched and
/ Or bulk by and the child to be curved and / or bent
It is desirable to use an elevated one. Hereinafter, the present invention will be described in detail.

[Front and back layers] The front and back layers of the inorganic molded plate of the present invention comprise 30 to 60% by weight of cement, 30 to 60% by weight of a silicic acid-containing substance, and 0% of pearlite.
A cured product of mixture A with 15% by weight, flakes and / or wood flour 5-25% by weight. The above cement is Portland cement, blast furnace cement, silica cement,
Fly ash cement, encompasses various cements such as alumina cement, and the silicic acid-containing substance is, for example, silica sand, silica sand, silica fume, blast furnace slag,
It includes various inorganic powders containing silicic acid such as fly ash, shirasu balloon, perlite, and powder of wood cement board waste containing silicate substances. The cement and the silicate-containing substance react and harden by a calcium silicate reaction. In order to smooth the hardening due to such a calcium silicate reaction, 30-60% by weight of cement and 30-60% by weight of a silicic acid-containing substance are contained in the mixture A constituting the front and back layers of the inorganic molded plate of the present invention. It is necessary to be. Because pearlite reduces the weight of the manufactured inorganic molded plate and improves dimensional stability,
Although desirable for the present invention, it is not an essential component. However, when the content of pearlite is 15% by weight or more in the mixture, the strength of the obtained inorganic molded plate decreases and the front and back surfaces become rough. The flakes and / or wood flour are used as a reinforcing material for the front and back layers. The flakes preferably have an average mesh of 4.5 mm throughout the mesh of 10 mm and a thickness of 1 mm or less. Preferably, a material having a particle size of 10 to 30 mesh is used. The flakes have a stronger reinforcing effect than wood flour, but the flakes alone slightly reduce the denseness of the front and back layers obtained, while the wood flour alone slightly reduces the strength of the front and back layers obtained. Therefore, the flakes and the wood flour are preferably used in combination, in which case the mixing weight ratio of the flakes and the wood flour is about 80:20 to 20:80. However, the use of flakes alone or wood flour alone fully satisfies the objects of the present invention. When the flake and / or wood flour is less than 5% by weight in the mixture A, the strength of the front and back layers becomes insufficient, and when it is more than 25% by weight, the flame retardancy is reduced. Further, the front and back layers may be mixed with about 5 to 20% by weight of powder of waste wood cement board made of cement and wood reinforcing material. The wood cement board waste material powder is usually a fine powder having a size of 16 mesh or less, and the powder is filled in voids existing in the cement matrix to reinforce the cement matrix and improve the moisture absorption and absorption of the product. The mixture A constituting the front and back layers of the inorganic molded plate of the present invention further contains magnesium chloride, magnesium sulfate, calcium chloride, calcium sulfate, sodium aluminate, potassium aluminate, aluminum sulfate,
A curing accelerator such as water glass may be added.

[Core Layer] The core layer of the inorganic molded plate of the present invention comprises 30 to 60% by weight of cement, 30 to 60% by weight of a silicic acid-containing substance, and 0 to 100% of pearlite.
15% by weight, wood fiber bundle 5 to 25% by weight, flake 4 to
It is made of a cured product of the mixture B at 10% by weight and is porous.
The same cement, silicic acid-containing substance, and pearlite as those in the front and back layers are used in the same ratio. The wood fiber bundle is used as a reinforcing material for the core layer, and preferably has a diameter of about 0.1 to 2.0 mm, a length of about 2 to 35 mm, and more preferably 10 to 30 mm. Desirable wood fiber bundle shapes are bulked by branching and / or bending and / or bending. Such branches and / or curves and / or
Or sodium hydroxide, sodium sulfite, to produce a bulked wood fiber bundle by bending,
By immersing wood in a chemical such as calcium sulfite, or heating wood with steam, or as a binder for woody monofilaments contained in wood by using both the chemical immersion and steam heating. Lignin, hemicellulose, resin, etc., which are swollen without completely dissolving, leaving the binder, and defibrating.In particular, lignin is almost completely removed from the binder, and defibration is performed. It has a larger diameter than pulp fibers. When the wood fiber bundle is branched, the diameter is in the range of about 0.1 to 2.0 mm assuming the wood fiber bundle before branching, and the wood fiber bundle is bent and / or folded. If it is bent, the actual length of the wood fiber bundle is 10
It is desirable to be within the range of 30 mm. The wood fiber bundle is bulky due to the size and shape described above, and its bulk specific gravity is in a range of about 0.03 to 0.05 g / cm ³ . Here, a graduated cylinder having an inner diameter of 8 cm and a volume of 2,000 ml was filled with 2,000 ml of the wood fiber bundle in an absolutely dry state, the total weight was measured, and the weight of the graduated cylinder was subtracted from the total weight to obtain the wood fiber bundle. The weight of the wood fiber bundle is determined by placing the weight on the wood fiber bundle placed on the wood fiber bundle filled with a disk that just fits into the inner diameter of the graduated cylinder, and weighing 1 kg on the wood fiber bundle. It is determined by measuring the volume of the wood fiber bundle and dividing the weight (g) of the wood fiber bundle by the volume (cm ³ ). Branching the wood fiber bundle and / or
Alternatively, to increase the bulk by bending and / or bending, the degree of swelling and the degree of defibration of the binder are adjusted. The defibration is performed by, for example, a gliding disk, and the degree of defibration is adjusted by adjusting the disk gap of the gliding disk. The wood fiber bundles which have been made bulkier by the branching and / or bending and / or bending are entangled with each other in the mixture B at some distance, but the fiber bundles become pulp fibers. Since it has a large diameter, it has a certain degree of rigidity and is hardly entangled in a string. However, when the actual length of the wood fiber bundle becomes longer, the tendency of the wood fiber bundle to become entangled in a string even if it is 30 mm or less is increased. Therefore, in the present invention, the entanglement of the wood fiber bundle in the form of a thread is prevented without lowering the strength of the product by adding flakes. That is, when the flakes are added, the flakes enter the inside of the spiral wood fiber bundle and prevent the wood fiber bundle from changing from the spiral shape to the thread shape. The same flake as that used for the front and back layers is used as the flake. As described above, the flakes are added to the core layer by 4-10.
However, if the amount is less than 4% by weight, the effect of preventing the entanglement of the wood fiber bundle in a thread form is not significant, and if it exceeds 10% by weight, the strength of the product is adversely affected. In this way, the cement and the silicic acid-containing substance are entrapped between the entangled fiber bundles in the presence of the flakes. The flakes described above, in combination with the stiffness of the fiber bundle, maintain the distance between such fiber bundles and thus help maintain bulkiness. Therefore, when the dry production method is applied to the production of the inorganic molded plate of the present invention, a mixture containing the curable inorganic powder, the wood fiber bundle, and the flakes
B can be sufficiently loosened by mechanical stirring or the like, and it is extremely easy to uniformly spread the mixture B on a template. On the other hand, after the spraying, the wood fiber bundle in the presence of flakes is dispersed as described above. The curable inorganic powder is entangled by the entanglement through a certain distance, and a mat that does not lose its shape can be formed. Also in the product, in the matrix, the wood fiber bundle has a small specific gravity due to a specific reinforcing effect that the fiber bundles are tightly entangled through a certain distance in the presence of flakes as described above, so that the wood fiber bundle is light and relatively lightweight. It gives a core layer with high strength. In the present invention, in order to make the core layer porous, a method is generally applied in which thermoplastic foam particles are mixed with the mixture and cured, and the thermoplastic foam particles are heated and softened and shrunk. The mixture B
Mixing the thermoplastic plastic foam particles, already foamed to thermoplastic foam Tsubu以 out are, using a foamable thermoplastic plastic beads, said mixture B
Before or at the time of curing, the foamable thermoplastic plastic beads may be foamed to form thermoplastic foam particles. In this case, if a wood fiber bundle which is made bulky by branching and / or curving and / or bending is used, the structure of the mixture B becomes sparse, so that the foaming of the expandable thermoplastic beads is suppressed. There is an advantage that it is performed uniformly and smoothly. The expandable thermoplastic beads used in the present invention are thermoplastic beads such as polyethylene, polypropylene and polystyrene impregnated with a volatile foaming agent such as propane, butane, pentane and petroleum ether. The amount of the thermoplastic foam particles or the expandable thermoplastic beads is usually 0.1% in the mixture B.
5 to 5% by weight. If the amount of the thermoplastic foam particles or the expandable thermoplastic beads is 0.5% by weight or less, the proportion of pores in the core layer is reduced, resulting in insufficient insulation. weight%
When the above is satisfied, the proportion of organic matter in the inorganic molded plate of the present invention becomes excessive, and the flame retardancy of the inorganic molded plate of the present invention is reduced. Furthermore, similarly to the front and back layers, 5 to 20% by weight of wood cement board waste material powder may be added to the core layer.

[Manufacturing Method] As a manufacturing method of the inorganic molded plate of the present invention, it is desirable to adopt a dry manufacturing method in which the process can be easily performed and the apparatus is simple. In step 1 of the dry production method, the mixture A is sprayed on a template in a mat shape, and then the mixture B is sprayed on the mat in a mat shape, and the mixture A is further spread thereon.
Is sprayed in a mat form, and at this time, 30 to 45% by weight of water is added to each of the mixture A and the mixture B for a curing reaction. The addition of flakes to mixture B and the use of wood fiber bundles which have been bulked by the above-mentioned branching and / or bending and / or bending make the mixture B easier to unravel and evenly spread on the template. Easy to spray. In the continuous manufacturing method, a large number of the above-mentioned templates are placed on a belt conveyor. The raw material mixture sprayed on the template is pressed slightly by a roll or the like, if desired, and the mat is then pressed and pre-cured in step 2 in the presence of moisture to form a desired shape. The pressing conditions are usually a pressing pressure of 10 to 20 kgf / cm ² and a temperature of 60 to 80.
C. for about 20 to 30 hours, and heating is usually performed with steam. Pressing is performed by clamping the mat between two mold plates, but the mold plate surface may be given a predetermined shape, an uneven pattern, or the like. The pre-cured product obtained by the pressing pre-curing in step 2 is cured in an autoclave in step 3. The curing conditions are usually a pressure of 10 to 20 kgf / cm ² , a temperature of 160 to 180 ° C. and a time of about 5 to 10 hours. By the above autoclave curing, the calcium silicate reaction between the cement and the silicate-containing substance is completely performed, and when expandable thermoplastic beads are added to the core layer, the expandable thermoplastic beads are completely expanded. At the same time, the plastic foam particles formed by the foaming of the expandable thermoplastic beads melt and the foaming agent in the cells escapes to the outside world, and the plastic foam shrinks rapidly to form a large number of particles inside the core layer. Voids are formed. A plastic coating layer resulting from the thermoplastic foam particles is formed on the inner wall surface of the pore. Thus, the inorganic molded plate of the present invention is produced. The thickness of the front and back layers of the inorganic molded plate of the present invention is usually 10 to 30% of the total thickness, and the density is usually 0.9 to 1.1 g / cm. ^{Assume 3} .

[0008]

In the present invention, both the front and back layers and the core layer contain 30 to 60% by weight of cement and 30 to 60% by weight of a silicic acid-containing substance.
, The curing of each layer based on the calcium silicate reaction proceeds smoothly. Furthermore, when the dry manufacturing method is adopted, the calcium silicate reaction proceeds almost completely due to autoclave curing and hardens in the final dimensional state of the molded body, so that the molded body once hardened is less affected by the external environment. The dimensional stability of the product is improved. Since the front and back layers contain 5 to 25% by weight of flakes and / or wood flour, the front and back layers have high density and rich surface smoothness. Further, since the core layer contains 5 to 25% by weight of the wood fiber bundle and 4 to 10% by weight of the flakes and is porous, the core layer is light in weight and rich in sound insulation and heat insulation. In addition, in the front and back layers and the core layer, the wood reinforcing material such as flakes, wood flour, and wood fiber bundle is contained at 25% by weight or less, so that the inorganic molded plate of the present invention is flame-retardant. 4 to 10% by weight in the core layer
The presence of the flakes in the range prevents the entanglement of the wood fiber bundles in a thread form, and when the inorganic molded plate of the present invention is manufactured by the dry manufacturing method, the raw material mixture can be evenly spread on the template. , give the average one cushioning property to the core layer
It is Ru can. If a wood fiber bundle used for the core layer is made bulky by branching and / or bending and / or bending, the core layer has a low bulk specific gravity but does not decrease in strength, and also has a foaming property. The foaming of the thermoplastic thermoplastic beads is also performed uniformly and smoothly. Although embossing is Ru applied to front and back surfaces of the inorganic molded plate of the present invention, the case in a dense front and back layers and the homogeneity and porosity quite sharp and deep embossing by a core layer having a therefore uniform cushioning It can be applied uniformly .

[0009]

Examples [Examples 1 to 10] (1) Table 1 shows the formulation of the mixture A (for the front and back layers).

[Table 1] * 1: Use a mesh with an average mesh of 4.5 mm and an average thickness of 0.6 mm. * 2: Use of an average particle size of 20 mesh. * 3: Weight% based on cement. (2) Table 2 shows the formulation of the mixture B (for the core layer).

[Table 2] * 1: The same as mixture A is used. * 2: Branched and / or curved and / or bent with an average particle size of 1.0 mm and a length of 20 mm is used. * 3: Weight% based on cement. (3) To each of the mixture A, 30% by weight of water based on the solid content, and to each of the mixture B, 35% by weight of water based on the solid content were added, and the mixture A was sprayed on a lower mold plate. An 8 mm thick mat was formed, and the mixture B was further sprayed on the mat to a thickness of 50 mm.
A thick mat, and further spray the mixture A on the mat.
After forming a mat having a thickness of mm and pressing the upper mold plate from above, press hardening is performed at a pressure of 10 kgf / cm ² and a temperature of 70 ° C. for 25 hours. The obtained laminate was a plate having a thickness of 18 mm. The laminate was then cured in an autoclave at a pressure of 15 kgf / cm ² and a temperature of 165 ° C. for 7 hours. And the silicic acid-containing material are hardened by the calcium silicate reaction, and the expandable polystyrene beads of the core layer are expanded and then softened and shrunk.
In this way, the mixtures 1B, 2B, 3B, 4B, and 5B were combined with each of the mixtures 1A and 2A, and
0 inorganic molded plate sample was obtained.

Comparative Examples 1 and 2 (1) As mixture A, 1A and 2A shown in Table 1 of the Examples were used. (2) As the mixture B ', one having the formulation shown in Table 3 is used.

[Table 3] * 1: The same one as used in the examples is used. * 2:% by weight with respect to the cement. (3) Water was added to each of the mixture A and each of the mixture B 'in the same manner as in the example. Similarly, the inorganic plate samples of Comparative Examples 1 to 4 were prepared by the dry manufacturing method.
At this time, since the mixture B 'of the formulations 1B' and 2B 'had a thread-like entanglement of the wood fiber bundle, when the mixture B' was sprayed on the mat of the mixture A formed on the lower mold plate,
Some unevenness occurred.

[Evaluation of Physical Properties] With respect to the samples of Examples 1 to 10 and Comparative Examples 1 to 4, apparent specific gravity, bending strength, freeze-thaw resistance (freeze resistance),
Tables 4 and 5 show the results of measurement and evaluation of the surface condition.

[0012]

[Table 4]

[0013]

[Table 5] Physical property test conditions were the same as in Examples 1 to 10.

Referring to Tables 4 and 5, all of the samples of the examples are lightweight, have high strength, and have a good surface condition. Also in No. 10, the frost resistance is maintained and the surface is extremely dense and smooth. However, the samples of Comparative Examples 1 to 4 using the mixture B ′ to which no flake was added were mixed B ′.
Is difficult to apply evenly, and therefore the strength and surface condition are inferior to those of the examples.

[0015]

Therefore, in the present invention, it is light and strong, and the surface condition is dense and smooth .
There, very sharp and deep embossing uniformly formed was <br/> inorganic molded plate was obtained and the inorganic molded plate thus quotient
It has a very high value and can be easily mass-produced by a dry manufacturing method.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification code FI C04B 16:02) 111: 40 (56) References JP-A-3-218955 (JP, A) JP-A-6-199554 (JP) JP-A-3-146480 (JP, A) JP-A-61-136950 (JP, A) JP-A-54-157125 (JP, A) JP-B-63-1276 (JP, B2) (58) Field surveyed (Int.Cl. ⁶ , DB name) C04B 28/02 B28B 1/52 C04B 16:02

Claims (2)

(57) [Claims] 1. 30 to 60% by weight of cement, 30 to 60% by weight of silicic material, 0 to 15% by weight of perlite, 5 to 25% by weight of flakes and / or wood flour, and 30 of water
The mixture A was dispersed in a mat shape on a mold having an uneven pattern formed on the mold surface, and then 30 to 60% by weight of cement, 30 to 60% by weight of a silicic acid-containing substance, and pearlite. 0
１５15% by weight, wood fiber bundle 5-25% by weight, flake 4
-10% by weight, expandable thermoplastic beads.
Mixture B with 5-5% by weight and 30-45% by weight of water
To form a mat having a three-layer structure by spraying the mixture A thereon and forming a mat having a three-layer structure. Step 2 of pressing and pre-curing the mat having the three-layer structure. Step 3 of foaming the foamable thermoplastic plastic beads by heating and autoclaving the precured product and proceeding the curing. Process 3 for producing an inorganic molded plate comprising the above processes 1, 2 and 3 Wherein the wooden-fiber bundle production method of the inorganic molded plate according to claim 1, which is bulky by branched and / or curved and / or bent