JPH0818859B2 - Calcium silicate compact and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calcium silicate compact and a method for producing the same. More specifically, the present invention is a building material that is lightweight, tough, and has good workability, which is a good point of wood while improving the poor water resistance of wood such as warping and rottenness and the poor fire resistance of burning. A calcium silicate compact and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, various kinds of calcium silicate compacts have been proposed. For example, (1) 100 parts by weight of calcium silicate hydrate, hydraulic gypsum 10-1
A calcium silicate compact formed by molding and drying a slurry containing 50 parts by weight, 5 to 30 parts by weight of a polymer emulsion, a coagulant and reinforcing fibers (JP-A-54-160428).
Japanese Laid-Open Patent Publication No. 1) is proposed, and specifically, calcium silicate 1
Proposed to be 50 parts by weight of α-type hemihydrate gypsum, 12 parts by weight of carboxy-modified styrene-butadiene copolymer latex, 1.1 parts by weight of acrylamide polymer flocculant, and 6 parts by weight of glass fiber per 00 parts by weight. Has been done.

(2) A silica prepared by molding and drying a slurry comprising 100 parts by weight of calcium silicate, 1 to 30 parts by weight of reinforcing fibers, 1 to 40 parts by weight of latex, and 0.1 to 5 parts by weight of a dispersant. Calcium acid molded article (JP-A-62-62
-126053), specifically, 7 parts by weight of glass fiber, 3 parts by weight of a melamine condensate-based dispersant, and latex 10 with respect to 100 parts by weight of calcium silicate.
It has been proposed that it consists of parts by weight. Here, the conventional dispersant is a dispersant for cement or the like, and specifically, lignin-based, higher polyhydric alcohol sulfonate-based, alkyl sulfonate, and high-condensate-based polyoxyethylene alkyl. Examples include ether type and melamine condensation type,
The uniform dispersion of each raw material is attempted during the production of the molded body.

Further, (3) a calcium silicate compact (JP-A-62-235276) is proposed, in which a slurry comprising 100 parts by weight of calcium silicate and 1 to 15 parts by weight of an ettringite- forming substance is molded and dried. 1. Glass fiber 7 parts by weight, latex 5 parts by weight, dispersant 3 parts by weight, swelling agent 2.
It has been proposed to consist of 5 parts by weight. Further, in the conventional method for producing a calcium silicate compact, the pressure molding is at most 60 kgf / cm ² .

[0005]

SUMMARY OF THE INVENTION However, the conventional
Since the molded body of (1) contains a large amount of hydraulic gypsum, there is room for improvement in water resistance as a building material, and the fire resistance due to decomposition of gypsum crystals at high temperatures is also insufficient,
It is difficult to obtain a calcium silicate compact having water resistance and fire resistance. The molded product of (2) attempts to solve the problems of water resistance and fire resistance found in the molded product of (1), but there is still room for improvement in bending strength and heat resistance of the molded product. .

Further, the molded body of (3) is one in which an ettringite- forming substance is added, but this also has room for improvement in fire resistance similarly to (1), and if the amount of generation increases, it will be at high temperature. It becomes unsuitable as a building material because the warpage deformation becomes large due to the decomposition of crystals. In addition, the above (1),
(2) In both cases, the workability and fire resistance improve as the amount of polymer emulsion or latex increases, but if the amount is 10 parts by weight or more relative to 100 parts by weight of calcium silicate, the bending strength will decrease. However, at high temperatures, heat shrinkage and warpage appear remarkably, making it unsuitable as a building material. An object of the present invention is to provide a calcium silicate compact which is free from heat shrinkage and warpage at high temperatures, has excellent water resistance and fire resistance, and has sufficient bending strength, and a method for producing the same.

[0007]

DISCLOSURE OF THE INVENTION The present inventors have found that by adding an appropriate amount of reinforcing fiber and latex to calcium silicate and a new amount of pulp, it is possible to obtain extremely high water resistance and fire resistance. It was found that a calcium silicate compact having sufficient bending strength can be formed. That is, the present invention was made based on the above findings, and 100 parts by weight of calcium silicate, 2 to 8 parts by weight of reinforcing fibers, 3 to 9 parts by weight of latex (solid weight, hereinafter, latte).
All parts by weight of solids represent parts by weight of solids. ) And 1 to 6 parts by weight of pulp are provided to provide a calcium silicate compact, which achieves the above object.

Hereinafter, preferred embodiments of the calcium silicate compact and the method for producing the same according to the present invention will be described in detail. The calcium silicate compact according to the present invention basically comprises calcium silicate, reinforcing fibers, latex and pal.
Is an essential ingredient. As calcium silicate, it is known per se (for example, JP-A-62-123053).
JP-A-62-235276 and JP-A-64
-38227, etc. ) Can be used, and specifically, tobermorite, zonotolite, or tobermorite obtained by a hydrothermal synthesis reaction of calcareous materials such as quick lime, slaked lime, and slag with siliceous materials such as silica stone, silica sand, and cement, and water. Mention may be made of these mixed calcium silicate hydrates.

The reinforcing fibers may be inorganic fibers or organic fibers, but preferably glass fibers, carbon fibers, alumina fibers, steel fibers or the like having fire resistance. In particular,
Glass fiber is excellent in fire resistance and cost, improves the strength and impact resistance of the molded body, and makes the dehydration filtration property at the time of molding good. In consideration of dispersibility, moldability, reinforcing effect, etc., the reinforcing fiber preferably has a fiber diameter of 8 to 13 μm and a length of 6 to 25 mm, and the amount used is 100 parts by weight of calcium silicate based on the results described below. 2 to 8 parts by weight, preferably 4 to 6
Good parts by weight.

The latex is known per se (eg, JP-A-62-123053 and JP-B-62).
Those described in JP-A-3109. ) Can be used in emulsion type or solution type, and specifically, styrene-butadiene copolymer, carboxyl group-modified styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, butadiene copolymer. Examples thereof include a polymer, a methyl methacrylate-butadiene copolymer, and an ethylene-propylene copolymer. Among them, a styrene-butadiene copolymer latex containing a carboxyl group is preferable, and this latex has an action of adhering and fixing calcium silicates by cross-linking, thereby preventing scattering of powder particles and the like during cutting, screwing. , It improves the holding power of nails and water resistance and forms a board that is preferable as a building material. The amount of latex used is 3 to 9 parts by weight, and preferably 4 to 7 parts by weight, based on 100 parts by weight of calcium silicate, based on the results described later.

[0011] Examples of the above-mentioned pulp, if example example, mention may be made of paper, kraft paper, those of virgin pulp in general. The pulp, as well as a uniform dispersion of the calcium silicate and glass fibers, may serve to improve the fixing of the latex, the molded body without using a large amount of latex as in the prior art is not less than the performance It is possible to provide a product that is obtained and has a low cost. The amount of dispersant used is 1
6 parts by weight, preferably 2 to 4 parts by weight, and within this range, JIS A 1321 (flame retardancy test method)
It is possible to sufficiently obtain the result of satisfying the non-combustible material.
In addition to the above components, a polymer flocculant, a dispersant, a colorant,
Or sulfur-based vulcanizing agent, additives such as fused imparting agent may be suitably added to the latex. For example, the aggregating agent of the slurry is not particularly limited, and may be an anionic type, a cation type, or a combined use.

Next, the method for producing a calcium silicate compact according to the present invention will be described. From 100 parts by weight of calcium silicate, 2 to 8 parts by weight of reinforcing fiber, 3 to 9 parts by weight of latex and 1 to 6 parts by weight of pulp. It can be manufactured by molding and drying the slurry. Further, when the slurry is molded, general molding such as papermaking molding and extrusion molding may be used, but dehydration pressure molding is particularly preferable. Less than,
Detailing a preferred embodiment of the method for manufacturing a dewatering that by the pressing calcium silicate molded product.

The water content in the slurry is calcium silicate.
100 to 100 parts by weight of 1200 to 3900 parts by weight
The range is desirable, and such a slurry has a pressing force of 70 to 1
50kgf / cm², Especially 80-100kgf / cm², Dehydration time 5
It is preferable to perform dehydration molding in less than a minute. High in the above slurry
Can pressurize, conventional 30-60kgf / cm²Addition of
Different from pressure, dehydration molding is sufficient even if dehydration time is 5 minutes or less
Is achieved, and it is also necessary to add a large amount of coagulant.
Absent. Also, conventionally, depending on the slurry concentration,
There is a concentration limit that causes material separation, which leads to high cost.
However, with the above slurry components, the concentration
There are few limits, and the pressing force is 70-150kgf / cm. ²If so,
The surface hardness, bending strength, impact resistance, and secondary processing characteristics of the shape are
improves. The drying temperature after molding is in the range of 130 to 150 ° C.
Calcium silicate, which is desirable
The specific gravity of the um molded product is 0.10 to 1.20.
It can be.

[0014]

EXAMPLES Examples of the calcium silicate compact and the method for producing the same according to the present invention will be described below. However,
The present invention is not limited to the following examples. still,
The test results in the examples are based on the following method. (1) Bending strength: JIS A 1408 (No. 4 test piece)
According to. (2) Workability: Surface condition, coating condition, router processing was performed and comparison with wood was performed. (3) Heat resistance: The molded body was heated in an electric furnace at 1000 ° C. for 2 hours, and the presence or absence of harmful gas generation, thickness and linear shrinkage, and deformation measurement. (4) Water resistance: After the molded body is immersed in water at 20 ° C. for 24 hours,
Judgment based on the appearance of the wood mouth and dimensional stability due to water absorption. (5) Evaluation: Excellent, Good, Fair, Poor

Example 1 Silica stone powder and slaked lime were mixed so that the molar pressure of SiO ₂ : CaO was 1: 1 and 12 times amount of water was added to the total weight of CaO and SiO _2. Was added, and a hydrothermal synthesis reaction was carried out at a temperature of 198 ° C. for 7 hours while stirring in an autoclave to obtain a calcium silicate hydrate slurry. To this slurry, 100 parts by weight of calcium silicate is latex [ manufactured by Nippon Zeon Co., Ltd., trade name: LX416 ( styre
-Butadiene copolymer latex)] 5 parts by weight, pulp (manufactured by Hyogo Pulp Co., Ltd., trade name: cellofiber) 2
Parts by weight, glass fiber (manufactured by Nippon Electric Glass Co., Ltd., trade name:
(ACS, ECS) 5 parts by weight were added and mixed. The obtained slurry is poured into a 300 × 300 mm mold and 100 kgf
Dehydration and pressurization at a pressure of / cm ² and drying at 150 ° C. for 6 hours,
A calcium silicate compact was obtained.

Comparative Example 1 A molded product was obtained in the same manner as in Example 1 except that pulp was not used. Table 1 shows the results. (Comparative Example 2) A molded product was obtained in the same manner as in Example 1 except that the amount of glass fiber used was less than 2 parts by weight. Table 1 shows the results.
Shown in Comparative Example 3 A molded product was obtained in the same manner as in Example 1 except that the amount of latex used was doubled to 10 parts by weight. Table 1 shows the results.

(Comparative Example 4) 50 parts by weight of α-type hemihydrate gypsum, 12 parts of latex, 1.1 parts by weight of acrylamide polymer flocculant, and 100 parts by weight of calcium silicate as in Example 1 and glass A molded body was produced in the same manner as in Example 1 using 6 parts by weight of the fiber. The evaluation results are shown in Table 1. (Comparative Example 5) Calcium silicate 100 as in Example 1
A molded product was obtained in the same manner as in Example 1 except that 7 parts by weight of glass fiber, 3 parts by weight of melamine condensate-based dispersant and 10 parts by weight of latex were used with respect to parts by weight. The evaluation results are shown in Table 1. Comparative Example 6 Calcium silicate 100 as in Example 1
A molded product was obtained in the same manner as in Example 1 except that 7 parts by weight of glass fiber, 5 parts by weight of latex, 3 parts by weight of dispersant, and 2.5 parts by weight of expanding agent were used with respect to parts by weight. The results are shown in Evaluation Table 1.

[0018]

[Table 1]

(Examples 2 to 4) Table 2 shows the length of the glass fiber.
A molded product was obtained in the same manner as in Example 1 except that the change was made as shown in FIG. The evaluation results are shown in Table 2.

[0020]

[Table 2]

(Examples 5 to 9) Molded articles were obtained in the same manner as in Example 1 except that the dehydration pressure was changed as shown in Table 3. The results are shown in Table 3.

[0022]

[Table 3]

[0023]

The calcium silicate compact and the method for producing the same according to the present invention are free from heat shrinkage and warpage at high temperatures, have excellent water resistance and fire resistance, and have sufficient bending strength. You can

Claims (3)

[Claims] 1. 100 parts by weight of calcium silicate, 2 to 8 parts by weight of reinforcing fiber, 3 to 9 parts by weight of latex (solid weight)
And a calcium silicate compact formed by shaping a slurry comprising 1 to 6 parts by weight of pulp . 2. The reinforcing fiber is glass fiber and has a diameter of 8 to 1.
The calcium silicate compact according to claim 1, which has a length of 3 μm and a length of 6 to 25 mm. 3. The method for producing a calcium silicate compact according to claim 1, wherein the slurry is applied with a pressure of 70 to 15
A process for producing a calcium silicate compact, which comprises dehydrating and press-molding at 0 kgf / cm ² and a dehydration time of 5 minutes or less, and then drying.