JP2002256252A - Aqueous sealer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a nonpollution type aqueous vinylidene chloride sealer composition for inorganic building materials such as houses having excellent moisture permeability resistance and designability at a low cost. SOLUTION: This aqueous sealer composition comprises (I) a vinylidene chloride emulsion and (A) a talc represented by the formula (1) Mg3 Si4 O10 (OH)2 (1) and is characterized as comprising the talc (A) in an amount of 10-300 pts.wt. based on 100 pts.wt. of solids in the vinylidene chloride emulsion (I).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a sealer composition for an inorganic building material which is excellent in moisture resistance by containing vinylidene chloride emulsion as a main component and further containing talc and hydrotalcites.

[0002]

[Prior art and its problems] Inorganic building materials include building materials,
It is used as a civil engineering material and an industrial material. Specifically, there are an asbestos cement board, a wood chip cement board, a pulp cement board, a lightweight cellular concrete board, a calcium silicate board and the like.

[0003] Recently, exterior wallboards and tiles made of the above-mentioned materials used for houses and the like tend to be reduced in weight in order to improve workability of houses. As an effect, the water permeability of the inorganic substrate is poor, and the moisture permeability is poor. For example, in a humid place, a warp is caused by moisture, or a problem of frost damage cracking due to freezing of moisture in the inorganic substrate is caused. Sometimes.

[0004] To solve the above problem, an organic solvent-type sealer composition is applied to an inorganic substrate. The organic solvent-type sealer composition is excellent in stability and coating film performance of the organic solvent-type sealer composition. Use VOCs from an environmental standpoint
(Volatile Organic Compound)
It was not preferable in terms of regulations, environmental preservation measures such as ISO14001, and increased costs compared to water.

[0005] In water, a sealer composition containing a vinylidene chloride-based emulsion as a main component gives a good coating film having moisture resistance and mechanical strength at low cost.
However, vinylidene chloride-based emulsions show strong acidity (pH 1-2) because they contain hydrogen chloride in water. Therefore, when producing an aqueous sealer composition using a vinylidene chloride-based emulsion, it is necessary to select additives such as a pigment dispersant, a pigment, and an antifoaming agent that are stable in a strongly acidic region of pH 1 to 2. There was a restriction on the formulation of such as.

As a countermeasure, it is possible to relatively easily produce an aqueous sealer composition by previously neutralizing a vinylidene chloride-based emulsion with a base such as ammonia. However, dehydrochlorination occurs over time, and the aqueous sealer composition becomes strongly acidic. For this reason, the aqueous sealer composition is liable to cause aggregation, precipitation, and the like of pigments and additives, and has a problem in stability. In addition, since it becomes strongly acidic, corrosion of containers, coating equipment, and the like was also a problem.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies in consideration of the above problems, and as a result, have found that aqueous sealer compositions for inorganic building materials used as building materials, civil engineering materials and industrial materials. In the above, by blending a pigment paste containing talc, more preferably hydrotalcites, with a vinylidene chloride emulsion, the above problems were solved and the present invention was completed.

That is, the present invention provides: It contains a vinylidene chloride emulsion (I) and a talc (A) represented by the formula (1).
Is the solid content of the vinylidene chloride emulsion (I) 100
1. Aqueous sealer composition characterized by containing 10 to 300 parts by weight with respect to parts by weight, Mg ₃ Si ₄ O ₁₀ (OH) ₂ Formula (1) Solid content of vinylidene chloride emulsion (I) 10
Relative to 0 parts by weight, aqueous sealer composition according hydrotalcite (B) is to the paragraph (1), characterized in that it contains 0.1 to 20 parts by weight of the formula (2), _{Mg Y-X ^{Alx (OH) 2Y · a n-}} X / Y · mH 2 O (2) ^{(wherein, a n-n-valent} anion, for example ^OH -, Cl
^- , A monovalent anion such as CO ₃ ^2-, etc., wherein x is a number satisfying 0 <x, y is a number satisfying 2x ≦ y, and m is a number satisfying 0 <m. ) 3. 3. The aqueous sealer composition according to item 1 or 2, wherein the vinylidene chloride content is 30 to 85% by weight based on the total solid content of the monomers constituting the vinylidene chloride emulsion (I). . 4. A pigment paste (II) containing talc (A) and a nonionic surfactant (C) is blended with a vinylidene chloride emulsion (I) in an aqueous sealer composition. 4. The aqueous sealer composition according to item 1, or A pigment paste (II) containing talc (A), hydrotalcites (B), and nonionic surfactant (C) is blended with the vinylidene chloride emulsion (I) in the aqueous sealer composition. 5. The aqueous sealer composition according to any one of items 1 to 3, Items 1 to 5 in which the average particle diameter of talc (A) is 2 to 6.5 μm and the oil absorption is in the range of 20 to 45 ml / 100 g.
The present invention relates to the aqueous sealer composition according to any one of the above items.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail. The aqueous sealer composition is produced by blending the pigment paste (II) with the vinylidene chloride emulsion (I) and stirring.

The reason why the vinylidene chloride-based emulsion is used in the aqueous sealer composition for inorganic building materials is that it is closely adhered to the inorganic building material as a base material, and is excellent in moisture permeability and mechanical strength.

The vinylidene chloride emulsion (I) is
A vinylidene chloride-based emulsion in which vinylidene chloride is an essential component and vinyl chloride, other monomers, and the like are copolymerized, is used after further adding other additives.

As monomers to be used, vinylidene chloride (H ₂ C = CCl ₂ ), vinyl chloride (H ₂ C = CHC)
l) can form a coating film by polymerization alone, but contains chlorine (Cl) in its monomer.

Other monomers include methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-methylpentyl acrylate, n-octyl Acrylate, 2-ethylhexyl acrylate, n-decyl acrylate, n-dodecyl acrylate, n-octadecyl acrylate, etc., as alkyl methacrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, Isobutyl methacrylate, n-pentyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, Le Pen Chill methacrylate,
One or more selected from n-octyl methacrylate, 2-ethylhexyl methacrylate, n-decyl methacrylate, n-dodecyl methacrylate, n-octadecyl methacrylate, cyclohexyl methacrylate and the like can be used.

In addition, styrene, α-methylstyrene, glycidyl acrylate, glycidyl methacrylate,
3,4-epoxycyclohexylmethyl acrylate,
Epoxy group-containing unsaturated compounds such as 3,4-epoxycyclohexylmethyl methacrylate, hydroxyl group-containing unsaturated compounds such as hydroxyalkyl acrylate and hydroxyalkyl methacrylate, and carboxyl group-containing unsaturated compounds such as acrylic acid and methacrylic acid are appropriately used. Compounds that have been blended and subjected to a copolymerization reaction can be used.

The vinylidene chloride-based emulsion (I) of the present invention is characterized in that the proportion of vinylidene chloride is 30 to 85% by weight based on the total solid content of each of the constituent monomers.

If the proportion of vinylidene chloride in the vinylidene chloride-based emulsion (I) exceeds 85% by weight, the formed coating film becomes hard and the adhesion is reduced, and if the proportion of vinylidene chloride is less than 30% by weight, the anti-permeability is reduced. Poor wetness.

The above-mentioned vinylidene chloride emulsion (I)
The copolymerization reaction of can be carried out by an emulsion polymerization method or the like, which is a general emulsion production method.However, in consideration of the stability of the emulsion, vinyl chloride and vinylidene chloride are excluded. It is desirable to use seed polymerization in which polymerization is performed first as a seed polymer.

The molecular weight of the vinylidene chloride emulsion is in the range of 30,000 to 200,000 in terms of polymerization average molecular weight. Three
If it is less than 000, the durability to the solvent used for top coating etc. is insufficient. When it is larger than 200,000, it is difficult to stably produce a vinylidene chloride emulsion by a general polymerization method. The weight average molecular weight is a value measured by GPC (gel permeation chromatography) and converted into polystyrene.

The pigment paste (II) is prepared by adding talc (A), hydrotalcites (B), nonionic surfactant (C), other pigments, a solvent, water and the like, and then adding a shaker, a ball mill, and a sand mill. The pigment paste (II) can be produced by dispersing by a dispersing means such as the above.
Talc (A) is made of talc or hydrated magnesium silicate (3M
The _{gO · 4H 2 O · H 2} O) and also said general formula, a compound represented by the following formula (1) as a main component, containing some impurities than a natural product. Mg ₃ Si ₄ O ₁₀ (OH) ₂ Formula (1) The shape is monoclinic, plate-like (leaf-like), scale-like, and the like. Or called soapstone, it has a soft, smooth feel. Hardness 1 to 1.5, specific gravity 2.7 to 2.
8. Often used after being processed by mechanical pulverization or the like, the average particle diameter is about 2 to 35 μm, and the oil absorption is 20 to
The pH of the water-soluble material is in the range of 80 to 1
0 alkaline. The present invention is effective in general talc as described above, but preferably,
When a flat talc (A) having an average particle diameter of talc (A) of 2 to 6.5 μm and an oil absorption of 20 to 45 ml / 100 g is used, moisture permeability, equipment corrosion resistance, and stability are improved. It is effective by improvement.

Here, when the average particle diameter is less than 2 μm, talc (A) cannot be oriented in parallel in the coating film, so that the effect of moisture permeation resistance and the like is reduced. On the other hand, if the average particle size exceeds 6.5 μm, the stability of the sealer composition decreases.

The oil absorption of talc is 20 ml / 100.
If it is less than g, dispersion becomes poor and the stability of the sealer composition is reduced. On the other hand, if the oil absorption exceeds 45 ml / 100 g, aggregation and sedimentation of the pigment occur, and the stability decreases.

The talc (A) is used in an amount of 1 part by weight based on 100 parts by weight of the solid content of the vinylidene chloride emulsion (I).
It may be contained in an amount of 0 to 300 parts by weight, preferably 50 to 200 parts by weight. If the content is less than 10 parts by weight, there is no effect on moisture permeability and improvement of equipment corrosion, and if it exceeds 300 parts by weight, the coating film becomes hard and the adhesion is reduced.

Next, the hydrotalcites (B) are generically referred to as compounds represented by the following formula (2). In the present invention, by blending with talc (A), it contributes to improvement in moisture resistance and water resistance.

[0024] ^{_{Mg Y-X Alx (OH)}} 2Y · A n- X / Y · mH 2 O (2) ^{(wherein, A n-n-valent} anion, for example ^OH -, Cl
^- , A monovalent anion such as CO ₃ ^2-, etc., wherein x is a number satisfying 0 <x, y is a number satisfying 2x ≦ y, and m is a number satisfying 0 <m. ) The hydrotalcites (B) are compounds having a layered structure having a large adsorptivity, and are industrially used as antacids and heat stabilizers. In particular, in the above formula, a compound represented by the following formula (3) is preferable. Mg _1-X Alx (OH) ₂ · (CO ₃ ) _{X / 2} · mH ₂ O Formula (3) (0 <x ≦ 0.5) Specific examples of the hydrotalcite (B) compound include, for example, Mg _4-3 Al ₂ (OH) _12-6 CO _{3.
mH 2 O, Mg 6 Al 2} (OH) 16 CO 3 · 4H
_{2 O, Mg 4.5 Al 2 (} OH) 13 CO 3 · 3.5H
₂ O, Mg ₄ Al ₂ (OH) ₁₂ CO ₃ .3H ₂ O, as well as Mg _0.7 Al _0.3 O _{1.15, and the} like.
DHT-4A, Kyoward 500, 1
000, 2000, 2100, and 2200 (trade name, manufactured by Kyowa Chemical Industry Co., Ltd.) and the like, and these can be used alone or in combination. Among them, especially Mg _4-3 A
_{l 2 (OH) 12-6 CO 3} · mH 2 O being preferred.

The hydrotalcites (B) used in the present invention have a specific surface area (BET) of 1 to 50 m ² /
g, especially those in the range of ^{2 to} 40 m ² / g.
The larger the specific surface area, the greater the amount of ions adsorbed per unit weight, which has the effect of keeping the pH of the aqueous sealer composition in a weakly acidic region.

Further, the hydrotalcites (B) are preferably fine powders having a particle size distribution of not more than 1 μm and not less than 80%, especially not less than 85%. If the particle size distribution is less than 80%, the amount of adsorption per unit weight is undesirably small.

The hydrotalcites (B) used in the present invention can be subjected to a surface treatment as required. Examples of such a surface treatment agent include organic fatty acids, anionic surfactants, silane coupling agents, titanate coupling agents, esters of glycerin and a fatty acid, and the like.

Specific examples of such a surface treatment agent include:
For example, higher fatty acids such as stearic acid, oleic acid, and lauric acid; anionic surfactants such as sodium stearate, sodium oleate, and sodium laurylbenzenesulfonate; and vinyl triethoxysilane; Silane-based or titanate-based coupling agents such as γ-methacryloxypropyltriethoxysilane, isopropyltriiristearoyl titanate, isopropyltridecylbenzenesulfonyl titanate, etc .; And esters of glycerin and a fatty acid such as

The content of the hydrotalcites (B) is
0.1 to 20 parts by weight, preferably 1 to 1 part by weight, per 100 parts by weight of the solid content of the vinylidene chloride emulsion (I)
It is preferable to add 0 parts by weight.

If the amount is less than 0.1 part by weight, the aqueous sealer composition becomes strongly acidic, and the stability is deteriorated. On the other hand, when the amount exceeds 20 parts by weight, problems tend to occur in the storage properties of the paint and the adhesion of the formed coating film.

The pigment paste (II) is prepared by using a nonionic surfactant (C) in addition to talc (A) and hydrotalcite (B) to prepare a coloring pigment such as titanium white and carbon black, an extender pigment, Other pigments such as rust preventive pigments, solvents, water and the like are added and dispersed as needed.

Examples of the nonionic surfactant (C) include polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene derivatives, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, glycerin fatty acid esters, and polyoxyethylene sorbitan fatty acid esters. Oxyethylene fatty acid esters, polyoxyethylene alkylamines, alkylalkanolamides and the like can be mentioned. The amount of the nonionic surfactant (C) to be added is preferably 0.1 to 30% by weight based on the solid content of the vinylidene chloride-based emulsion (I).

The present invention further comprises, if necessary, a plasticizer,
Surfactant, colloidal silica, organic solvent, curing catalyst,
Adds matting agents, preservatives, fungicides, anti-algal agents, leveling agents, anti-settling agents, anti-sagging agents, film forming aids, thickeners, flow regulators, defoamers, etc. Things can be manufactured.

As the means for coating the aqueous sealer composition, conventionally known coating means, for example, rollers, brushes, sprays, dippings, flow coaters (curtain flow coaters), bar coaters, blade coaters, roll coaters, gates It can be painted by a method such as a coater.

The drying equipment is, for example, a hot air electric drying oven, a hot air gas drying oven, a jet heater or the like.
It is preferable to dry at 0 to 200 ° C. for about 30 seconds to 20 minutes. As for the inorganic building materials, there are coated articles which are shipped as they are after applying the above-mentioned aqueous sealer composition, and there are also coated articles which are shipped after further applying a top coat thereon.

[0036]

The effect of the present invention is that talc and hydrotalcites have an alkalinity in water-solubilized content, and therefore, when contained in a sealer composition, the pH of the composition is weakened to less than 6-7. Since it is acidic, the workability of preventing aggregation and sedimentation can be improved, and the aqueous sealer composition can be easily produced.

In addition, no problems such as sedimentation of the pigment were observed even with the elapse of time, and a low-cost, environmentally friendly sealer composition having good stability, moisture permeability, corrosion of equipment, and physical properties of the coating film was found. The reason why the moisture resistance and the physical properties of the coating film were improved was that talc and hydrotalcite reacted with chloride ions in the sealer composition, and the passage of moisture that would pass through the coating film by containing talc was blocked. It is possible that it comes off.

More specifically, exterior wall boards and tiles made of the above-mentioned materials which are recently used for houses and the like tend to be reduced in weight in order to improve the workability of houses. In a place where the material is inferior in water resistance and moisture permeability, and in a humid place, the problem of warping due to moisture and freezing damage cracking due to freezing of water in the inorganic base material could be improved.

Conventionally, an organic solvent type sealer composition has been applied to an inorganic substrate. However, since an organic solvent type sealer composition uses a large amount of an organic solvent, VOC (Volatile Organic Compound) is environmentally friendly. : Volatile organic compounds) Although it was not preferable from the viewpoint of insufficient environmental preservation measures such as regulations and ISO 14001, and increased costs compared to water, the present invention is water-based and thus is not environmentally friendly. Surface and cost reduction.

[0040]

EXAMPLES The present invention will be described in detail with reference to examples.
The present invention is not limited by this. still,
“%” Indicates “% by weight”. Vinylidene chloride emulsion no. Production Example of Table 1 As in Example 1, 60 parts of vinylidene chloride, 25 parts of vinyl chloride, 5 parts of methyl acrylate, 5 parts of methyl methacrylate, and 5 parts of methacrylic acid were mixed to prepare a monomer mixture.

While 100 parts of water, 0.2 parts of sodium alkylsulfonate and 0.1 parts of sodium persulfate were charged into a 5 L flask, 20 parts of the monomer mixture were charged at once, and the remaining 80 parts were charged. In about 8 hours. At the same time, 1.0 part of sodium alkyl sulfonate was continuously dropped, and water was added to adjust the solid content to 40% by weight. 1 was obtained. Vinylidene chloride emulsion no. Production Example of No. 2 No. 2, except for vinylidene chloride emulsion No. 2. In the same manner as in Production Example 1, a vinylidene chloride emulsion having a solid content of 40% was prepared. 2 was obtained. Vinylidene chloride emulsion no. Production example of No. 3 No. 3, except for vinylidene chloride emulsion No. 3. In the same manner as in Production Example 1, a vinylidene chloride emulsion having a solid content of 40% was prepared. 3 was obtained.

[0042]

[Table 1]

Production Example of Pigment Paste A EA152 (Daiichi Kogyo Chemical Co., Ltd., trade name, nonionic surfactant) 6.25 parts (solid content: 5 parts), CR-97
(Ishihara Sangyo Co., Ltd., trade name, titanium white) 50 parts, Micron White 5000A (Hayashi Chemical Co., Ltd., trade name, talc) 50 parts, DHT-4A (Kyowa Chemical Co., trade name, hydrotalcites, etc.) 3) BYK-011
(Manufactured by Big Chemie Japan, trade name, surface conditioner) 1
And water, were mixed and dispersed with a paint shaker to obtain a pigment paste A having a solid content of 50% by weight. Examples of Production of Pigment Paste B and Pigment Paste C Pigment paste B and pigment paste C were obtained by the same operation with the blending contents shown in Table 2.

[0044]

[Table 2]

Example 1 Aqueous sealer composition no. 1 Vinylidene chloride emulsion No. 1 obtained in the above Production Example. Aqueous sealer composition No. 1 having a solid content of 40% was prepared by blending 300 parts (solid content: 150 parts) of pigment paste A with 500 parts (solid content: 200 parts). 1 was obtained. Example 2 and Comparative Examples 1 to 3 With the composition as shown in Table 3, the aqueous sealer composition No. 2-N
o. 5 was obtained.

[0046]

[Table 3]

Preparation of Inorganic Building Material Sheet A composition comprising 60 parts of Portland cement, 50 parts of silica sand, 5 parts of pulp fiber, 3 parts of sepiolite, 1 part of carbon black, and 120 parts of water is formed into a sheet by a papermaking method, and then press-molded. To produce an inorganic building material plate. Preparation of Test Plate Aqueous sealer composition No. was added to the inorganic building material plate prepared with the above composition. 1 to No. 5 was applied using an air spray so that the dry film thickness became 50 μm. Table 4 shows the test results.
Shown in

[0048]

[Table 4]

(Note 1) Moisture permeability: Each sealer composition No. 1 to No. After coating No. 4 on a tin plate to a film thickness of 50 μm, the coating film was peeled off with amalgam to obtain a free coating film. JIS Z 02 using this free coating film
08: moisture permeability was 25 g / m ² · 24 hours or less Δ: moisture permeability was 100 g / m ² · 24 hours or less ×: moisture permeability exceeded 100 g / m ² · 24 hours (Note 2) Paint stability: At the time of paint preparation, ◎: When the pigment paste is mixed with the emulsion, aggregation
Good: no sedimentation, no sedimentation even after standing for 24 hours. ○: When the pigment paste is mixed with the emulsion, aggregation /
There is no sedimentation and sedimentation is slightly observed after standing for 24 hours, but there is no problem as a product. △: When the pigment paste is mixed with the emulsion, coagulation and sedimentation occur unless vigorously stirred. ×: The pigment paste is added to the emulsion. When mixed, agglomeration and sedimentation occurs even with strong stirring. (Note 3) Equipment corrosivity: Untreated cold-rolled steel sheet (Fe) is immersed in the sealer composition and left at 20 ° C. After one week, the state of the cold-rolled steel sheet (Fe) after taking out and washing was observed. ○: Good without any problem △: Rust was observed on the edge portion of the steel sheet and on the general surface ×: Rust was observed on the entire surface of the steel sheet ( Note 4) Physical properties of coating film: each sealer composition No. 1 to N
o. After coating No. 4 on a tin plate to a film thickness of 50 μm, the coating film was peeled off with amalgam to obtain a free coating film.
Using this free coating film, the elongation was measured using Tensilon ("Tensilon UTN II-20", trade name, manufactured by Toyo Baldwin Co., Ltd.). The tensile speed was set at 20 ° C.-4 mm / min, and the elongation of 10 samples was evaluated. ○: elongation 20% or more Δ: elongation 11 to 19% ×: elongation 10% or less

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2E001 DB01 FA00 GA03 HD00 JA06 MA01 4H017 AA04 AA27 AA31 AA39 AB10 AB17 AC10 AC16 AD06 AE03

Claims (6)

[Claims] 1. A vinylidene chloride emulsion (I),
And talc (A) represented by the formula (1), wherein the talc (A) is contained in an amount of 10 to 300 parts by weight based on 100 parts by weight of the solid content of the vinylidene chloride-based emulsion (I). Aqueous sealer composition. Mg ₃ Si ₄ O ₁₀ (OH) ₂ Formula (1) 2. The hydrotalcites (B) represented by the formula (2) are contained in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of a solid content of the vinylidene chloride emulsion (I). The aqueous sealer composition according to claim 1. ^{_{Mg Y-X Alx (OH)}} 2Y · A n- X / Y · mH 2 O (2) ^{(wherein, A n-n-valent} anion, for example ^OH -, Cl
^- , A monovalent anion such as CO ₃ ^2-, etc., wherein x is a number satisfying 0 <x, y is a number satisfying 2x ≦ y, and m is a number satisfying 0 <m. ) 3. The vinylidene chloride emulsion according to claim 1, wherein the vinylidene chloride content is 30 to 85% by weight based on the total solid content of the monomers constituting the vinylidene chloride emulsion (I). Aqueous sealer composition. 4. A pigment paste (II) containing talc (A) and a nonionic surfactant (C) is blended with a vinylidene chloride emulsion (I) in an aqueous sealer composition. The aqueous sealer composition according to any one of claims 1 to 3. 5. A pigment paste (II) containing talc (A), hydrotalcites (B), and a nonionic surfactant (C) is blended with a vinylidene chloride emulsion (I) in an aqueous sealer composition. The aqueous sealer composition according to any one of claims 1 to 3, characterized in that: 6. The talc (A) has an average particle size of 2 to 6.5.
The aqueous sealer composition according to any one of claims 1 to 5, wherein the aqueous sealer composition has an oil absorption of 20 to 45 ml / 100 g.