JPH0543357A - Production of inorganic hydraulic plate - Google Patents

Abstract

PURPOSE:To largely improve productivity. CONSTITUTION:Semi-cured inorganic hydraulic plates are coated with an aqueous coating, piled up on each other, aged and cured. The coating uses an alkyd resin alone or its mixture with an acrylic resin as a binder and contains a pigment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an inorganic hydraulic board material.

[0002]

2. Description of the Related Art Conventionally, when curing a semi-cured inorganic hydraulic board material (hereinafter referred to as a cake) typified by ALC, a huge floor area is required if the curing is performed by arranging them one by one. , Multiple sheets are piled up and cured.

In this case, since the cakes are in a semi-cured state, they have adhesiveness, and if they are piled up nervelessly, they may adhere to each other and become difficult to peel off, or some may be peeled off. Therefore, in order to prevent such adhesion, the following measures have been taken.

1) After stacking a plurality of cakes, the pre-incubation time is set to be long, and the hardness of the cakes is increased, so that even if some water vapor enters the interface, it becomes difficult for the cakes to adhere, so that the curing is started. 2) When stacking the cakes, spread a polyester film one by one on the stacking surface for curing. 3) When stacking the cakes, apply a mold release paint and stack them for curing.

[0005]

However, in the case of 1), there is a drawback that the adhesive tends to adhere to the lower part even if it takes a considerable time for the pre-introduction before curing, and a place for the pre-introduction is required. However, it has a disadvantage that it is not preferable in terms of equipment and productivity.

In the case of 2), linear marks remain on the ALC after curing due to wrinkles generated on the film during stacking, or the film begins to melt during the curing process of the autoclave, causing stains and the like. In addition to the drawbacks that cause it, there is a drawback that the cost required for the film, the labor for laying the film, and the cost increase.

Further, in 3), there is a drawback that the adhesion cannot be completely prevented due to the influence of the variation in the dry state of the release coating and the roughness and smoothness of the cake surface. When a top coat is applied to the above product, it also has a defect that causes defective adhesion between the release coating and the top coat.

[0008]

DISCLOSURE OF THE INVENTION The inventors of the present invention have not taken a significant amount of time and place for pre-introduction, and have not adversely affected the product or increased the cost, and have a variation in the drying of a releasable paint or a cake. The results of various studies and studies aimed at preventing the mutual adhesion of cakes without being affected by the surface accuracy of the product, eliminating various defects such as adversely affecting the coating of products, and requiring no complicated operations. It has been found that the above object can be achieved by applying a specific substance to a cake.

Thus, according to the present invention, a water-based paint containing an alkyd resin alone or a mixture of an alkyd resin and an acrylic resin and a pigment is applied to the surface of the cake, and the cakes coated with the paint are stacked to cure and cure the inorganic water. It is to provide a method for manufacturing a hard plate material. In the present invention, the inorganic hydraulic plate material is typically ALC, but other molded products such as cement, gypsum, hydraulic lime and the like can be mentioned. The present invention will be described below using ALC.

The cake in ALC refers to a cured state in which a steel ball of 40 mmφ is allowed to fall freely from a height of 4.9 cm and the diameter of the recess is 15 to 25 mm.
Prior to curing, on the surface of ALC in such a state,
More specifically, the surface on one side that is the overlapping surface of the ALCs,
Preferably, a water-based paint effective for preventing adhesion is applied on the upper surface. As the water-based paint effective for preventing such adhesion, a water-dilutable binder (binder) of an alkyd resin alone or a mixture of an alkyd resin and an acrylic resin, a pigment, and water as a diluting agent are essential components, and further necessary. Accordingly, various additives, modifiers and a small amount of organic solvent are mixed.

As the alkyd resin, a polybasic acid and a polyhydric alcohol, or a resin obtained by a condensation reaction by adding a modifying agent to the polybasic acid, or a double bond of the resin obtained by the condensation reaction, a styrene monomer, an acrylic acid and a meta A resin obtained by graft-polymerizing an alkyl ester monomer of acrylic acid having 1 to 8 carbon atoms, an acrylic acid monomer, a methacrylic acid monomer and the like is used. Above all, oil length 0 to 80, alcohol excess 8 to 1
A resin having 3% and an acid value of 8 to 70 is preferable.

Examples of the polybasic acid include phthalic anhydride, isophthalic acid, terephthalic acid, succinic anhydride, adipic acid, azelaic acid, sebacic acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride and 1,4-cyclohexanedicarboxylic acid. , Maleic anhydride, fumaric acid, itaconic acid, trimellitic anhydride, and pyromellitic anhydride.

As the polyhydric alcohol, ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, triethylene glycol, glycerin, trimethylolethane, trimethylolpropane, penta Examples include erythritol and dipentaerythritol. Examples of the modifier include benzoic acid, p-tert-butylbenzoic acid and fatty acid.

This resin is used after being dissolved or dispersed in a mixture of water and a hydrophilic solvent or neutralized with ammonia water or amines to be dispersed or dissolved in water or a mixture of water and a hydrophilic solvent. It is possible.

Particularly in the present invention, a substance that is hydrolyzed by heated steam in the presence of an alkaline component is preferable. Examples of the acrylic resin include alkyl ester monomers having 1 to 8 carbon atoms of acrylic acid and 1 to 1 carbon atoms of methacrylic acid.
A homopolymer or copolymer of the alkyl ester monomer of 8 or a copolymer of these monomers with a copolymerizable monomer is used.

Among them, acrylic acid, methacrylic acid, itaconic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, glycidyl acrylate, glycidyl methacrylate, acrylamide, methacrylamide, N-methylolacrylamide and N- Emulsion resins obtained by appropriately combining functional monomers such as methylol methacrylamide and monomers such as styrene, vinyltoluene, acrylonitrile, methacrylonitrile, vinyl chloride and butadiene and polymerizing in the presence of an emulsifier according to a conventional method are preferable. The molecular weight of these acrylic emulsion resins is about 50,000 to 300,000, preferably 8
It is advantageously between 10,000 and 200,000.

Acrylic resin has a minimum film forming temperature (hereinafter M
A material having a temperature of 30 ° C. or higher (referred to as FT) can be used, and a material having a temperature of 45 ° C. or higher is preferably difficult to be integrated. The acrylic resin may be either a normal dry type or a baked type,
Furthermore, a self-crosslinking type resin in which zinc oxide, a metal complex salt, a hydrazide compound, etc. are used in combination is also usable. Acrylic resin is not always an essential component only for the purpose of preventing the integration of plate materials, but by adding this resin, it is possible to prevent the pigment component from becoming powdery and to exert the function as a colored sealer layer. Is possible.

The mixing ratio (solid content ratio) of the alkyd resin and the acrylic resin may be in the range of 100 to 66: 0 to 34 parts, but is preferably 98 to 75: 2 to 25.

The pigment may be either an inorganic pigment or an organic pigment, but an inorganic pigment is preferable from the viewpoint of heat resistance, hot water resistance and alkali resistance. Specific examples thereof include titanium oxide, iron oxide yellow, iron oxide rust, color pigments such as carbon black, and extender pigments such as calcium carbonate, talc, kaolin, and barium sulfate, but are not limited thereto. Not what is done. The pigment is effective in preventing unification due to adhesion between plate materials and preventing color spots after curing of ALC autoclave.

The total amount of these alkyd resin and acrylic resin and the amount of the pigment and water are 8 to 33:10.
-30 (above solid content): 37 to 82 parts by weight can be used, but preferably 11 to 28:15 to 25: 4.
It is suitable to add 7 to 74 parts by weight.

If desired, various dispersants, thickeners, defoaming agents, antifungal agents, film forming aids and the like can be added. When applying such a paint to a cake, the amount applied is 2
0 to 300 g / m ² , preferably 40 to 200 g / m ^2.
It is suitable to apply so that As a means for applying such a paint to the cake, an ordinary coating method can be used, but it is preferable to apply by a non-contact type coating means such as air spray, airless spray, shower coater, flow coater, etc. ..

Next, the paint-coated cakes are stacked. The time for stacking the cakes is when the coating film is in a wet state, specifically within 4 minutes after coating, or when the coating film has cured to such an extent that the coating film is not damaged when stacked, specifically at about 100 ° C. It is preferably dried for 3 minutes or more. In addition, when stacking the cakes to such an extent that the coating film is damaged when stacked, there is a risk that the coating film adheres to the other adjacent cake and, as a result, the cakes are integrated.

The stacked uncured ALCs are then autoclaved and cured. The cured ALC thus obtained does not stick to each other and has virtually no adverse effect on the product.

As a method for molding the cake, there are a method in which a slurry as a raw material is cast in a mold and cured and molded, and a method in which the slurry is continuously cured by supplying the slurry in an endless belt shape. Either is fine.

[0025]

【Example】

Example 1 Air was blown into a cement containing 27% by weight of cement, 30% by weight of silica sand, 3% by weight of lime and 39.4% by weight of water, and 0.6% by weight of a foaming agent of a protein hydrolysis system. While stirring and introducing, an ALC slurry having a specific gravity adjusted to 0.8 was obtained. This slurry is placed in a mold and 40 mmφ
The iron ball of No. 2 was allowed to fall freely from a height of 4.9 cm and hardened to such an extent that a 25 mm recess was formed on the surface of the projecting body. This was made into a cake having a width of 0.6 m, a length of 3 m, and a thickness of 0.1 m, and 15 pieces were taken out.

On the other hand, glycerin / adipic acid = 39.8
A condensation reaction of 8: 42.2 (parts by weight) was carried out to obtain an alkyd resin having an acid value of 10 (yield: 71.7 parts by weight), which was isopropylate alcohol / water = 17.92 / 53.78 (parts by weight). Diluted. The excess alcohol ratio of this resin is 124
%Met.

36 parts of the oil-free alkyd varnish (solid content 50%) thus obtained and styrene / methyl methacrylate / butyl acrylate = 15/55/30
A coating consisting of 5 parts by weight of a copolymer (MFT 50 ° C.) emulsion (solid content 48%), 10 parts titanium white, 10 parts calcium carbonate, 1.5 parts additive, and 38.5 parts water. I prepared it. This paint was airless sprayed on one surface of each of the above 15 cakes so that the coating amount was 100 g / m ² (wet). This is put in an autoclave by stacking 15 sheets within 40 seconds, and the pressure is increased to 10 atm at 180 ° C.
I kept it for a long time and let it cure. When the state of adhesion of the cured product after the curing was examined, no adhesion phenomenon was found in any of them, and no defects such as color spots were observed on the surface of the cured product.

Example 2 Cement 25% by weight, silica sand 3
0% by weight, gypsum 2% by weight, lime 5% by weight, water 35.
4% by weight was mixed into a slurry, and 0.1% by weight of a surfactant containing a higher alcohol sulfate as a component and 2.5% by weight of water were foamed together with air in a foaming machine and mixed to give a specific gravity of 0. A foamed slurry adjusted to 8 was obtained.
This slurry was cast into a mold and semi-cured to the same extent as in Example 1. Width 0.9m, length 3m, thickness 0.1
18 pieces were taken out into a cake having a size of m.

On the other hand, soybean oil fatty acid / phthalic anhydride / ethylene glycol / pentaerythritol = 14.12 / 1
An alkyd resin having an acid value of 41, an oil length of 38, and an alcohol excess of 9% was obtained by a condensation reaction of 7.0 / 6.04 / 4.0 (parts by weight) (yield 37.6 parts). This resin was neutralized with 2.9 parts of triethylamine, 20 parts of monobutyl glycol ether, 10 parts of isopropyl alcohol, and 26.4 parts of water.
Diluted in the club. 50 parts of the alkyd varnish (solid content 40%) thus obtained, 14.5 parts of titanium white, 0.5 part of iron oxide yellow, 10 parts of barium sulfate, 1.5 parts of additive,
A paint consisting of 23.5 parts of water was prepared.

This coating composition was air-sprayed onto the surface of the above 18 cakes so that the coating amount was 75 g / m ² (wet). 18 sheets were piled up within 60 seconds and placed in an autoclave, and kept at 180 ° C. and 10 atm for 7 hours for curing. When the state of adhesion of the cured product after the curing was examined, no adhesion phenomenon was observed in any case, and no inconvenience such as color spots on the surface of the cured product was observed.

Example 3 Cement 26% by weight, silica sand 3
AL with a specific gravity of 0.8 by thoroughly stirring and introducing air containing 0.6% by weight of a proteolytic foaming agent into 0% by weight, 4% by weight of lime, and 39.4% by weight of water.
A C slurry was obtained. The slurry was cast into a mold and semi-cured to the same extent as in Example 1. Width 0.6m,
A cake having a length of 3 m and a thickness of 0.1 m was prepared and 16 pieces were taken out.

On the other hand, tall oil fatty acid / phthalic anhydride / ethylene glycol / pentaerythritol = 25.23 /
A condensation reaction of 30.37 / 10.79 / 7.15 (parts by weight) was performed to obtain an alkyd resin having an acid value of 45, an oil length of 39, and an alcohol excess of 9% (yield 68.2%). The alkyd resin was diluted with monobutyl glycol ether to a solid content of 70%. Further, 53 parts of alkyd resin was graft-polymerized with 0.6 part of methyl methacrylate and 1.2 parts of isobutyl methacrylate.

Next, this was neutralized with 3.7 parts of triethylamine and diluted with 5.5 parts of monobutyl glycol, 10 parts of isobutyl alcohol and 25.5 parts of water to obtain an acrylated alkyd varnish (solid content 40%). Obtained. Add 25 parts of this acrylated alkyd varnish with methyl methacrylate /
Butyl acrylate = 70/30 (parts by weight) copolymer (MFT 90 ° C or higher) emulsion (solid content 36%)
A paint consisting of 10 parts, titanium white 10 parts, calcium carbonate 10 parts, additive 1 part and water 44 parts was prepared. The coating amount of this paint was 120 g / m on the surface of the 16 cakes.
Airless spray to ² (wet), 40
Within a second, they were piled up and put in an autoclave, and kept at 180 ° C. for 10 hours under 10 atmospheres for curing. When the state of adhesion of the cured product after the curing was examined, no adhesion phenomenon was found in any of them, and no defects such as color spots were observed on the surface of the cured product.

[Comparative Example 1] Cake 1 was prepared in the same manner as in Example 1.
I took out five. On the other hand, styrene / methyl methacrylate / butyl acrylate copolymer (MFT50 ° C)
Of 48% solids emulsion 38 parts and titanium white 10
Part, 10 parts of calcium carbonate, 1 part of additive, 41 parts of water, a coating amount of 10 parts on the surface of the previous 15 cakes.
Airless spray to 0 g / m ² (wet), stack 15 pieces within 40 seconds and put in autoclave 1
It was kept at 80 ° C for 10 hours at 10 atmospheres for curing. When the state of adhesion of the cured body after the curing was examined, it was barely peeled off from the upper three sheets, but the lower 12 sheets were integrated and could not be peeled off.

[0035]

EFFECTS OF THE INVENTION Since a large number of cakes can be stacked and cured, the productivity can be greatly improved and the space at the production site can be reduced.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Hirata 1150 Hazawa-machi, Kanagawa-ku, Yokohama, Kanagawa Asahi Glass Co., Ltd. Central Research Laboratory (72) Inventor Hiroshi Nakano 1150, Hazawa-machi, Kanagawa-ku, Yokohama, Japan Asahi Glass Co., Ltd. (72) Inventor Kazumasa Saegusa 4-8-17 Ishiodai, Kasugai City, Aichi Prefecture (72) Inventor Akira Tomizawa 860-31 Yabe Town, Totsuka Ward, Yokohama City, Kanagawa Prefecture

Claims (2)

[Claims] 1. A semi-curable inorganic hydraulic material obtained by applying a water-based coating material containing an alkyd resin alone or a mixture of an alkyd resin and an acrylic resin and a pigment to the surface of a semi-curable inorganic hydraulic board material, and then applying the coating material. A method for producing an inorganic hydraulic board material in which the board materials are stacked, cured and cured. 2. The curing is an autoclave curing.
The method for producing an inorganic hydraulic board material.