JP2020081977A - Decoration method - Google Patents

Abstract

To provide a decoration method by which a new construction coating, which has excellent finishability, adherence and so on with respect to an existing wall surface having an uneven pattern and comprising an existing coating, can be formed while taking advantage of the uneven pattern.SOLUTION: According to this decoration method, in a work for coating an existing wall surface deteriorated over long-term with a primer coating material and a top coating material in this order, the primer coating material contains a non-aqueous solvent (A), a resin component (B), and a thickner (C), the non-aqueous solvent (A) contains a non-aqueous solvent at an aniline point of 12 to 70°C, the resin component (B) comprises one or more kinds of compounds of which at least one kind is a compound having a reactive silyl group, a solid content of the resin component (B) is 25 to 75% by weight in the primer coating material, and the primer coating material has a pigment volume concentration of below 30%.SELECTED DRAWING: None

Description

The present invention relates to a makeup method applicable to buildings and the like.

Conventionally, concrete, mortar, various plate-shaped wall materials, etc. have been used for wall surfaces of buildings and the like. Among them, for example, as a plate-like wall material, a material in which an uneven pattern is provided on the surface thereof to give a three-dimensional effect and which is coated for protection and beauty is often used.

Since the wall surface composed of such a plate-shaped wall material is exposed to the outdoors for a long period of time, the surface of the plate-shaped wall material deteriorates due to the effects of sunlight, rainfall, dust, etc. The original aesthetic appearance of the material deteriorates over time.

Japanese Unexamined Patent Publication No. 6-306305 describes a method in which a deteriorated film is coated with a sealer, and then an aqueous thick film type elastic paint is applied as an overcoat material.

JP-A-6-306305

However, on the deteriorated surface such as a plate-shaped wall material having a concavo-convex pattern, even if makeup is applied using the method of the above-mentioned patent document, the concavo-convex pattern is damaged in the finished state after applying the overcoat material, or It is difficult to obtain practically satisfactory results, such as the occurrence of areas lacking in adhesion.

The present invention has been made in view of the problems as described above, and having an uneven pattern, with respect to an existing wall surface provided with an existing coating film, while utilizing the uneven pattern, is excellent in finishability, adhesion, etc. It is an object of the present invention to provide a makeup method capable of forming a new coating.

As a result of earnest studies to achieve the above-mentioned object, the present inventor has come up with a method for sequentially applying a specific undercoat material and an overcoat material to the existing wall surface as described above, and to complete the present invention. Arrived

That is, the present invention has the following features.
1. A method of applying an undercoat material and an overcoat material in order to an existing wall surface that has deteriorated over time,
The existing wall surface has an uneven pattern on the surface, and is provided with an existing coating,
The undercoat material contains a non-aqueous solvent (A), a resin component (B), and a thickener (C),
The non-aqueous solvent (A) contains a non-aqueous solvent having an aniline point of 12 to 70°C,
The resin component (B) is composed of one or more compounds, and at least one of the compounds is a compound having a reactive silyl group,
The solid content of the resin component (B) is 25 to 75% by weight in the undercoat material,
The undercoat material has a pigment volume concentration of less than 30%, which is a makeup method.
2. The resin component (B) is composed of one or more compounds,
At least one of the compounds is a resin having a weight average molecular weight of 10,000 to 150,000. Makeup method described.
3. The existing wall surface has a concavo-convex pattern on the surface and is composed of a plurality of plate-shaped wall materials provided with existing coatings. Or 2. Makeup method described in.

ADVANTAGE OF THE INVENTION According to this invention, it is possible to form a new coating film excellent in finish and adhesion on an existing wall surface having an uneven coating and having an existing coating while utilizing the uneven pattern.

Hereinafter, modes for carrying out the present invention will be described.

The present invention can be applied to existing wall surfaces such as buildings and civil engineering structures. Such an existing wall surface is composed of at least a base material and an existing coating. Examples of the base material include concrete, mortar, metal, wood, glass, and various plate-shaped wall materials. Among them, the plate-shaped wall material includes, for example, an inorganic hardened body containing, as a main component, any of cement, calcium silicate, lime, gypsum and the like. Specific examples of such plate-like wall materials include, for example, cement board, extruded board, slate board, PC board, ALC board, fiber reinforced cement board, siding board, ceramic board, calcium silicate board, gypsum board, hard board. Examples include wood chip cement boards.

In the present invention, the existing wall surface is intended to have an uneven surface pattern. As the uneven pattern on the existing wall surface, various ones can be cited, for example, tile pattern, brick pattern, geometric pattern, striped pattern, lattice pattern, polka dot pattern, sand wall pattern, yuzu skin pattern, ripple pattern, etc. , A graphic pattern in which animals and plants are designed. Specifically, examples of the shape of the convex portion when the concavo-convex pattern is viewed from the front include a shape such as a square, a rectangle, a circle, an ellipse, a triangle, a rhombus, a polygon, and an irregular shape. Moreover, examples of the cross-sectional shape of the convex portion in the uneven pattern include a trapezoid, a square, a rectangle, a semicircle, a waveform, a staircase, a triangle, and a mountain shape. As the concave portion in the uneven pattern, for example, a flat concave portion is formed. The height difference between the concave portion and the convex portion may be constant or different at each site, but is preferably 20 mm or less, more preferably about 1 to 15 mm. Such a concavo-convex pattern may be provided on one or both of the base material and the existing coating.

In the existing wall surface of the present invention, the existing coating is provided on the surface of the base material. The existing coatings are various coatings that have already been coated on the above-mentioned substrate by in-situ coating, factory coating (line coating), or the like, and at least selected from organic coatings, inorganic coatings, organic-inorganic composite coatings, and the like. One type of coating is mentioned. Examples of existing coatings include colored coatings (enamel coatings, printed coatings, etc.), clear coatings, and laminated coatings of these coatings. These coatings are formed by coating and curing various coating materials on a substrate. .. Such a coating material may be any one of a room temperature dry type, a room temperature curing type, a bake curing type, an ultraviolet (UV) curing type, an electron beam curing type and the like.

Examples of the binder for such a coating material include organic binders such as acrylic resin, polyurethane resin, epoxy resin, fluororesin, alkyd resin, and polyester resin, or silicon resin, alkoxysilane, colloidal silica, silicate, and the like. Inorganic binders, organic-inorganic composite binders such as acrylic silicon resin, and the like can be mentioned.

In the present invention, in particular, the existing coating on the outermost surface is an inorganic coating (coating containing the inorganic binder), organic-inorganic composite coating (coating containing the organic-inorganic composite binder), fluororesin coating (containing the fluororesin It is suitable when it is one or more selected from (coating) and the like, and can be suitably applied to these clear coatings. Such existing coating may include photocatalytic titanium oxide or the like.

INDUSTRIAL APPLICABILITY The present invention can be applied as a refurbishing method when the existing wall surface as described above is deteriorated with age. The degree of aging deterioration is not particularly limited, but a wall surface that has been used for approximately 5 years or longer (and even 8 years or longer) can be the subject of the present invention.

As the existing wall surface of the present invention, it is preferable that a plurality of plate-shaped wall materials having an uneven pattern on the surface and provided with an existing coating are provided side by side. INDUSTRIAL APPLICABILITY The present invention can obtain an advantageous effect when an existing wall surface composed of such a plurality of plate-shaped wall materials is targeted. It is desirable that the uneven pattern is provided on at least the plate-shaped wall material itself.
A sealing material or a dry joint material may be filled in the connection portion between the plate-shaped wall materials. In this case, the plurality of plate-shaped wall materials are arranged side by side via the connecting portion, and the connecting portion is provided between the plate-shaped wall materials. The width of the connecting portion is preferably about 3 to 20 mm (more preferably 5 to 15 mm). A sealing material or a dry joint material is filled in the connecting portion.

In the present invention, an advantageous effect can be obtained when the existing wall surface is one in which the connecting portion between the plate-shaped wall materials is filled with the sealing material. The sealing material may be aged deterioration like the plate-shaped wall material, or may be newly cast before coating the undercoat material.

A general sealing material can be used, for example, a silicone-based sealing material, a modified silicone-based sealing material, a polysulfide-based sealing material, a modified polysulfide-based sealing material, an acrylic urethane-based sealing material, a polyurethane-based sealing material, an SBR. Examples include a system sealing material and a butyl rubber sealing material.
The method of filling the sealing material is not particularly limited, and for example, a known method using a gun, a spatula, or the like can be adopted.

Before filling the sealing material, processing such as back-up material filling or primer application may be performed in advance. As the backup material, for example, a foamed polyethylene backup material or the like can be used. As the primer, for example, a synthetic rubber-based primer, an acrylic-based primer, a urethane-based primer, an epoxy-based primer, a silicone resin-based primer, a silane-based primer or the like can be used.

The makeup method of the present invention sequentially coats (paints) an undercoat material and an overcoat material on an existing wall surface that has deteriorated over time as described above.

The undercoat material in the present invention contains a non-aqueous solvent (A), a resin component (B), and a thickener (C), of which the non-aqueous solvent (A) and the resin component (B) each contain a specific compound. It is characterized in that the solid content of the resin component (B) in the undercoat material and the value of the pigment volume concentration are within a specific range.

In the present invention, by using such an undercoat material, it is possible to form a new coating film having an uneven pattern and having excellent finish, adhesion and the like on an existing wall surface provided with the existing coating film. The mechanism of action in which such an effect is exhibited is not limited to the following, but the undercoating material in the present invention contains a thickener, the solid content of the resin component, and further the pigment volume concentration satisfies a specific condition. By doing so, it can be applied evenly along the irregularities of the existing wall surface, and the undercoat material applied to the existing wall surface exhibits excellent adhesion to the existing film due to the action of the specific non-aqueous solvent and resin component. It is presumed that what they do, etc. are contributing.

Examples of the non-aqueous solvent (A) in the undercoat material include aliphatic compounds such as n-heptane, n-hexane, n-pentane, n-octane, n-nonane, n-decane, n-undecane and n-dodecane. Hydrocarbon solvent, alicyclic hydrocarbon solvent such as methylcyclohexane and ethylcyclohexane, mixed solvent containing aliphatic hydrocarbon such as mineral spirit, petroleum ether, petroleum naphtha, solvent naphtha, kerosene and other petroleum solvent, isoparaffin Examples include system solvents, alcohol solvents, ether alcohol solvents, ether solvents, ester solvents, ether ester solvents, ketone solvents and the like. These may be used alone or in combination of two or more.

The undercoat material in the present invention contains a non-aqueous solvent having an aniline point of 12 to 70°C as the non-aqueous solvent (A). It is considered that such a non-aqueous solvent contributes to the improvement of the adhesiveness by swelling or dissolving the existing film to some extent. As the non-aqueous solvent having an aniline point of 12 to 70° C., for example, one or more selected from aliphatic hydrocarbon-containing mixed solvents such as mineral spirits, petroleum ethers such as petroleum ether, petroleum naphtha, solvent naphtha, kerosene and the like. It is suitable. In the present invention, as the non-aqueous solvent (A), an embodiment including a non-aqueous solvent having an aniline point of 30 to 65°C is more preferable, and the non-aqueous solvent having an aniline point of 30 to 65°C is added to the non-aqueous solvent (A). The embodiment containing 50 to 100% by weight is more preferable. The aniline point is a value measured by the method of JIS K2256. In the present invention, “α to β” have the same meaning as “α or more and β or less”.

The resin component (B) in the undercoat material is composed of one or more compounds, and at least one of the compounds is a compound having a reactive silyl group. It is considered that such a compound having a reactive silyl group contributes to the improvement of the adhesiveness due to its crosslinking reactivity.

The reactive silyl group is, for example, one in which one or more functional groups selected from an alkoxyl group, a hydroxyl group, a phenoxy group, a mercapto group, an amino group, halogen and the like are bonded to a silicon atom. Among these, an alkoxysilyl group in which an alkoxyl group is bonded to a silicon atom and/or a silanol group in which a hydroxyl group is bonded to a silicon atom are preferable.

As the compound having a reactive silyl group, for example, a reactive silyl group-containing vinyl compound, a tetraalkoxysilane compound, an alkylalkoxysilane compound, a silane coupling agent, or the like, or a compound derived therefrom (for example, a condensate or a modified compound) Products, polymers, copolymers, etc.). These may be used alone or in combination of two or more.

Among these, as the reactive silyl group-containing vinyl compound, for example, γ-(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropyltriethoxysilane, γ-(meth)acryloxypropylmethyldimethoxysilane. , Γ-(meth)acryloxypropylmethyldiethoxysilane and the like.

The reactive silyl group-containing vinyl compound can be used in the form of a resin (for example, an acrylic silicon resin) obtained by copolymerization with other monomers. Examples of such a monomer include (meth)acrylic acid alkyl ester, hydroxyl group-containing monomer, carboxyl group-containing monomer, amino group-containing monomer, pyridine-based monomer, nitrile group-containing monomer, amide group-containing monomer, epoxy group-containing monomer, Examples thereof include a carbonyl group-containing monomer, a fluorine-containing monomer, an aromatic monomer, an ultraviolet absorbing group-containing monomer, and a photostable group-containing monomer. These may be used alone or in combination of two or more. In addition, in this invention, the acrylic acid alkyl ester and the methacrylic acid alkyl ester are collectively described as the (meth)acrylic acid alkyl ester. A monomer is a general term for compounds having a polymerizable unsaturated double bond.

Examples of the tetraalkoxysilane compound include tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane and the like.

Examples of the alkylalkoxysilane compound include methyltrimethoxysilane, methyltriethoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltributoxysilane, propyltrimethoxysilane, propyltriethoxysilane, and butyl. Trimethoxysilane, butyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltributoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, dipropyldimethoxy Examples thereof include silane, dipropyldiethoxysilane, dibutyldimethoxysilane, dibutyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldibutoxysilane, methylphenyldimethoxysilane, and methylphenyldiethoxysilane.

Examples of the silane coupling agent include epoxy group-containing silanes such as γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyltriethoxysilane, and β-(3,4epoxycyclohexyl)ethyltrimethoxysilane. Coupling agent, N-β(aminoethyl)γ-aminopropylmethyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and other amino group-containing silane coupling agents, as well as isocyanate group-containing Examples thereof include a silane coupling agent, an isocyanurate group-containing silane coupling agent, and an acid anhydride group (carboxyl group)-containing silane coupling agent.

The resin component (B) can contain a compound other than the compound having a reactive silyl group. Examples of such compounds include various resins such as acrylic resins, polyester resins, polyether resins, polyurethane resins, fluororesins, vinyl acetate resins, and epoxy resins, or various compounds capable of producing these resins. Can be mentioned.

It is desirable that at least one resin component (B) is a resin having a weight average molecular weight of 10,000 to 150,000 (more preferably 40,000 to 120,000, further preferably 55,000 to 95,000). In the present invention, when the resin having such a weight average molecular weight is contained, the undercoat material can be easily applied uniformly along the irregularities of the existing wall surface, and the finish, the adhesion, etc. can be improved. The weight average molecular weight is a value obtained by measurement using gel permeation chromatography.

It is desirable that at least one kind of the resin component (B) is a non-aqueous dispersion type resin. The non-aqueous dispersion type resin is dispersed in the non-aqueous solvent (A) as resin particles, and has both a resin portion soluble in the non-aqueous solvent (A) and a resin portion insoluble in the non-aqueous solvent (A). .. When a resin having such a form is contained as the resin component (B), the undercoating material can be easily applied uniformly along the irregularities of the existing wall surface, and the finishability, the adhesion, etc. can be improved.

Such a resin has a glass transition point of preferably -40 to 60°C, more preferably -20 to 55°C. The glass transition temperature is a value obtained by the Fox calculation formula.

One of the preferred embodiments of the resin component (B) is, for example, an embodiment including a resin obtained by copolymerizing a reactive silyl group-containing vinyl compound and a monomer other than this. In this embodiment, for example, a (meth)acrylic acid alkyl ester or the like can be used as the monomer copolymerized with the reactive silyl group-containing vinyl compound. It is desirable that such a resin satisfy the conditions such as the above-mentioned weight average molecular weight and morphology.

In this embodiment, one or more selected from tetraalkoxysilane compounds, alkylalkoxysilane compounds, silane coupling agents and the like, or condensates and/or modified products thereof can be used in combination. A curing catalyst can also be used together. Examples of the curing catalyst include organic tin compounds, organic aluminum compounds, organic titanate compounds, acidic compounds, amine compounds, and alkaline compounds, and these can be used alone or in combination of two or more.

As one of preferred embodiments of the resin component (B), the resin component (B) is composed of two or more compounds, at least one of which is a hydroxyl group-containing resin, and at least one of which is polyisocyanate. The aspect which is a compound can also be mentioned. Both of these components can be reactively cured during the formation of the film to form a polyurethane resin film.

Specific examples of such an aspect include the following (1) and (2).
(1) A mode in which the resin component (B) is composed of two or more compounds, at least one of which is a hydroxyl group-containing resin having a reactive silyl group, and at least one of which is a polyisocyanate compound.
(2) The resin component (B) consists of three or more compounds, at least one of which is a hydroxyl group-containing resin, and at least one of which is a polyisocyanate compound,
An embodiment in which at least one kind is a compound having a reactive silyl group.

In the aspect of (1), as the hydroxyl group-containing resin having a reactive silyl group, for example, a resin containing a reactive silyl group-containing vinyl compound, (meth)acrylic acid alkyl ester, and a hydroxyl group-containing monomer as a resin constituent component is used. it can.

The above-mentioned (meth)acrylic acid alkyl ester is a compound having a (meth)acryloyl group and an alkyl group, and examples of the form of the alkyl group include linear, branched, and cyclic forms. Examples of such an alkyl (meth)acrylate ester include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, and (meth)acrylic acid. n-butyl, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, t-methacrylic acid t- Pentyl, 1-ethylpropyl (meth)acrylate, 2-methylbutyl (meth)acrylate, 3-methylbutyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, (meth)acrylic Acid 2-ethylbutyl, (meth)acrylic acid 2-methylpentyl, (meth)acrylic acid 4-methylpentyl, (meth)acrylic acid n-heptyl, (meth)acrylic acid n-octyl, (meth)acrylic acid isooctyl, 2-Ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, n-undecyl (meth)acrylate, n-lauryl (meth)acrylate and the like can be mentioned. These can be used alone or in combination of two or more.

Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, ( Examples thereof include hydroxyalkyl esters of (meth)acrylic acid such as 4-hydroxybutyl (meth)acrylic acid. These may be used alone or in combination of two or more.

It is desirable that such a hydroxyl group-containing resin satisfy the conditions such as the above-mentioned weight average molecular weight and morphology. The hydroxyl value is preferably 10 to 200 KOHmg/g, and more preferably 20 to 100 KOHmg/g. The hydroxyl value is a value represented by the number of mg of potassium hydroxide that is equimolar to the hydroxyl group contained in 1 g of the resin solid content.

The polyisocyanate compound has two or more isocyanate groups in one molecule and crosslinks with the hydroxyl group-containing resin to form a film.

Examples of the polyisocyanate compound include toluene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (pure-MDI), polymeric MDI, xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), water. XDI, hydrogenated MDI and the like, or derivatives thereof (for example, compounds obtained by a urethanization reaction, an allophanate reaction, an isocyanurate reaction, etc.), those having an allophanate group, an allophanate group and an isocyanurate group. Those which have it can also be used. These may be used alone or in combination of two or more.

In the aspect of (1) above, a compound having a reactive silyl group (excluding a hydroxyl group-containing resin having a reactive silyl group) can be used in combination, and examples thereof include a reactive silyl group-containing vinyl compound and tetraalkoxysilane. One or more selected from compounds, alkylalkoxysilane compounds, silane coupling agents, etc., or compounds derived therefrom (eg, condensates, modified products, polymers, copolymers, etc.) can be used. .. Further, in the above aspect (1), a curing catalyst may be used together.

In the above aspect (2), a hydroxyl group-containing resin (excluding those having a reactive silyl group) can be used. Examples of such a hydroxyl group-containing resin include polyether polyols, polyester polyols, acrylic polyols, polyisoprene polyols, carbonate polyols, and the like, and one or more of these can be used. It is desirable that such a hydroxyl group-containing resin satisfy the conditions such as the above-mentioned weight average molecular weight and morphology. The hydroxyl value of the hydroxyl group-containing resin is preferably 10 to 200 KOHmg/g, more preferably 20 to 100 KOHmg/g.

In the aspect of the above (2), it is desirable to include acrylic polyol (hydroxyl group-containing acrylic resin) as the hydroxyl group-containing resin. As the acrylic polyol, it is possible to use a polymer obtained by including (meth)acrylic acid alkyl ester, a hydroxyl group-containing monomer, and, if necessary, other monomer as a resin constituent component and polymerizing these. As the (meth)acrylic acid alkyl ester and the hydroxyl group-containing monomer, the same ones as described above can be used. Examples of the above-mentioned other monomers include a carboxyl group-containing monomer, an amino group-containing monomer, a pyridine group monomer, a nitrile group-containing monomer, an amide group-containing monomer, an epoxy group-containing monomer, a carbonyl group-containing monomer, an alkoxysilyl group-containing monomer, and an aroma. Group monomers, ultraviolet absorbing group-containing monomers, light stable group-containing monomers, and the like. These may be used alone or in combination of two or more.

As the polyisocyanate compound, the same ones as described above can be used.

In the aspect of the above (2), a compound having a reactive silyl group is used. As such a compound, for example, a reactive silyl group-containing vinyl compound, a tetraalkoxysilane compound, an alkylalkoxysilane compound, a silane coupling agent, or the like, or a compound derived therefrom (for example, a condensate, a modified product, a polymerization product) One or more selected from the group consisting of products, copolymers, etc.) can be used. In particular, in the above aspect (2), it is desirable to use a tetraalkoxysilane compound and/or a condensate thereof, or a modified product thereof. In the aspect of the above (2), a curing catalyst can be used together.

In the above aspects (1) and (2), the polyisocyanate compound preferably has a number average functional group number of 2-3, more preferably 2.05-2.6, and 2.1-. More preferably, it is 2.5. The use of such a polyisocyanate compound is particularly advantageous when the existing wall surface has a sealing material, and suppresses the swelling, cracking, peeling, etc. of the coating in the vicinity of the connecting portion filled with the sealing material, This can contribute to the effect of maintaining finishability for a long period of time.

The number average functional group number of the polyisocyanate compound is a value calculated by the following formula. In the following formula, the number average molecular weight of polyisocyanate is a value measured by gel filtration chromatography (GPC). The NCO content is the percentage of NCO groups in the polyisocyanate compound expressed in mass %. 42 in the formula is the molecular weight of the NCO group.
<Formula> Number average number of functional groups=(number average molecular weight×NCO content (%)/100)/42

The mixing ratio of the polyisocyanate compound may be set in consideration of the equivalent ratio of the isocyanate groups of the polyisocyanate compound to the hydroxyl groups of the hydroxyl group-containing resin, that is, the NCO/OH ratio. The NCO/OH ratio is preferably 0.6 to 1.4, more preferably 0.8 to 1.2. With such a ratio, the effects of the present invention can be sufficiently obtained.

The undercoat material in the present invention has a reactive silyl group content within the range of preferably 0.1 to 30% by weight, more preferably 0.3 to 20% by weight in terms of SiO _{2 in} the solid content of the component (B). A compound having When the mixing ratio of the compound having a reactive silyl group is within such a range, the adhesiveness between the existing coating and the undercoating material coating and the adhesiveness between the undercoating material coating and the overcoating material coating can be further enhanced. It is also suitable in terms of preventing cracking of the undercoat material coating and the topcoat material coating.

In addition, the SiO ₂ conversion is represented by the weight of the compound having a Si—O bond that remains as silica (SiO ₂ ) when completely hydrolyzed and then baked at 900° C. Generally, tetraalkoxysilanes, alkylalkoxysilanes and the like have the property of reacting with water to cause a hydrolysis reaction to form silanol, and further to cause a condensation reaction between silanols or silanol and alkoxy. When this reaction is carried out to the extreme, it becomes silica (SiO ₂ ). These reactions are
RO(Si(OR) ₂ O) _n R+(n+1)H ₂ O→nSiO ₂ +(2n+2)ROH
(R represents an alkyl group, n is an integer.)
It is expressed by the reaction formula. The SiO ₂ conversion in the present invention is a conversion of the amount of the remaining silica component based on this reaction formula.

Examples of the thickener (C) in the undercoat material include organic bentonite, finely divided silica, surface-treated calcium carbonate, amide wax, hydrogenated castor oil wax, benzylidene sorbitol, metal soap, polyethylene oxide, polymerized vegetable oil, and polycarboxylic acid amine. Salt etc. are mentioned. These may be used alone or in combination of two or more.

The mixing ratio of the thickener (C) is preferably 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, based on 100 parts by weight of the solid content of the resin component (B). When the mixing amount of the thickener (C) is within such a range, the undercoat material can be easily applied uniformly along the unevenness of the existing wall surface, and sufficient adhesiveness can be ensured. The effect can be stably obtained.

In the undercoat material, the solid content of the resin component (B) is 25 to 75% by weight, preferably 35 to 70% by weight in the undercoat material. Since the solid content of the resin component (B) in the undercoat material (the weight ratio of the resin component (B) in that when the weight of the undercoat material at the time of coating is taken as a standard) is such a ratio, the existing wall surface It is possible to apply the undercoat material evenly along the irregularities of (1), and it is possible to form a new coating film excellent in finish, adhesion, etc. while utilizing the irregularity pattern. When the solid content of the resin component (B) is less than the above value, the coating state of the undercoat material is likely to be non-uniform on the existing wall surface having an uneven pattern, and there is a risk that the finishability, the adhesion, etc. may be impaired. .. When the solid content of the resin component (B) exceeds the above value, it becomes difficult to apply the undercoat material along the unevenness of the existing wall surface, and it becomes difficult to obtain a finish utilizing the uneven pattern of the existing wall surface. The solid content is a value measured by the method of JIS K5601-1-2, the heating temperature is 105° C., and the heating time is 60 minutes.

The undercoat material has a pigment volume concentration of less than 30%, preferably 20% or less. An embodiment in which the undercoat material does not contain a pigment is also suitable. With such a ratio of the pigment volume concentration of the undercoat material, the undercoat material can be evenly applied along the unevenness of the existing wall surface, and while utilizing the uneven pattern, it has excellent finish and adhesion. It becomes possible to form a new coating. When the pigment volume concentration exceeds the above value, it becomes difficult to apply the undercoat material along the unevenness of the existing wall surface, and it becomes difficult to obtain a finish utilizing the uneven pattern of the existing wall surface. The pigment volume concentration is a volume percentage of the pigment contained in the dry coating film, and is a value calculated from the mixed amount of the resin component and the pigment constituting the undercoat material.

The undercoat material may contain various components other than the above components as long as the effects of the present invention are not significantly impaired. Such components include, for example, color pigments, extender pigments, aggregates, dyes, dehydrating agents, leveling agents, wetting agents, plasticizers, antifreezing agents, antiseptics, antifungal agents, antialgal agents, antibacterial agents, Examples thereof include a dispersant, a defoaming agent, an adsorbent, a fiber, a cross-linking agent, an ultraviolet absorber, a light stabilizer, an antioxidant and a catalyst. The undercoating material of the present invention can be produced by uniformly mixing the above-mentioned component (A), component (B), component (C) and, if necessary, the above-mentioned various components by a conventional method. The form of the undercoat material can be, for example, a one-pack type, a two-pack type, or a multi-pack type of more than that.

The undercoat material can be applied directly to the existing wall surface, but various pretreatments can be performed if necessary. Examples of the pretreatment include removal of an existing coating film that is significantly deteriorated, removal of contaminants and the like by high-pressure water washing, repair with putty, filler, and the like, restoration of surface shape, and the like. When a sealing material is newly cast on the existing wall surface, it is desirable to apply the undercoat material approximately 2 to 10 days after the sealing material is cast.

A known coating device can be used for coating the undercoat material. As the coating device, for example, a spray, a roller, a brush, a trowel or the like can be used.
The coating amount of the undercoat material may be appropriately set according to the surface shape of the existing wall surface, the coating equipment used, etc., but is preferably 0.03 to 0.5 kg/m ² , and more preferably 0.05 to 0. It is 0.3 kg/m ² . As long as the solid content of the resin component (B) satisfies the above conditions, the undercoating material can be appropriately diluted with a non-aqueous solvent during coating.

The viscosity of the undercoat material during coating is preferably 0.1 to 10 Pa·s, more preferably 0.2 to 5 Pa·s. When the viscosity of the undercoat material is within such a range, the effects of the present invention can be stably obtained. The viscosity mentioned here is a value obtained by measuring the viscosity at 20 rpm (the guideline value at the 4th rotation) with a BH type viscometer, and the measurement temperature is 23°C.

The drying time of the undercoat material is preferably 1 hour or more at room temperature (0 to 40° C.), more preferably about 2 to 200 hours.

In the present invention, the overcoat material is applied after the above-mentioned undercoat material is applied and dried. As the top coat material in the present invention, a material that can make the most of the uneven pattern on the existing wall surface is suitable. Specific examples of the top coat material that can be used include those containing a resin component and a color pigment.

Various resins can be used as the resin component in the overcoat material. Examples of the type of resin include vinyl acetate resin, polyester resin, alkyd resin, vinyl chloride resin, epoxy resin, acrylic resin, urethane resin, acrylic silicone resin, fluororesin, and the like, or a composite resin thereof. Among these, one kind or two or more kinds selected from acrylic resin, urethane resin, acrylic silicone resin, fluororesin and the like are preferable. Examples of the form of such a resin component include a water-soluble resin, a water-dispersible resin (resin emulsion), a solvent-soluble resin, a solventless resin, a non-aqueous dispersion resin, and a powder resin. Among them, one or more selected from water-soluble resins, water-dispersible resins, solvent-soluble resins and non-aqueous dispersion resins are suitable. Further, these resin components may have crosslinking reactivity. When a resin component having cross-linking reactivity is used, the durability, water resistance, weather resistance, chemical resistance, adhesion, etc. of the coating can be improved.

As the color pigment, for example, known inorganic color pigments, organic color pigments and the like can be used. By appropriately using one kind or two or more kinds of these color pigments, the topcoat material can be set to a desired color tone. The mixing ratio of the color pigment is preferably 1 to 500 parts by weight, more preferably 5 to 200 parts by weight, and further preferably 10 to 150 parts by weight with respect to 100 parts by weight of the solid content of the resin component.

Such an overcoat material may contain various components other than the above components as long as the effects of the present invention are not significantly impaired. Examples of such components include thickeners, film-forming aids, leveling agents, wetting agents, plasticizers, antifreezing agents, pH adjusting agents, extender pigments, preservatives, antifungal agents, antialgal agents, antibacterial agents. Agents, dispersants, defoamers, adsorbents, fibers, cross-linking agents, ultraviolet absorbers, light stabilizers, antioxidants, anti-staining agents, hydrophilizing agents, water repellents, catalysts, solvents, water, etc. Be done. The overcoat material of the present invention can be produced by uniformly mixing the resin component, the color pigment and, if necessary, the various components described above by a conventional method. The form of the overcoat material may be, for example, a one-pack type, a two-pack type, or a multi-pack type of more than that. The degree of gloss of the overcoat material includes, for example, gloss, 7 minutes gloss, 5 minutes gloss, 3 minutes gloss, and matte.

A known coating device can be used for coating the topcoat material. As the coating tool, for example, a spray, a roller, a brush or the like can be used.
The coating amount of the top coat material may be appropriately set according to the surface shape of the existing wall surface, the type of the top coat material, the type of coating equipment, etc., but is preferably 0.05 to 0.5 kg/m ² , and more preferably It is 0.1 to 0.4 kg/m ² . At the time of coating, the top coating material can be appropriately diluted if necessary.

In the present invention, the topcoat material may be used alone or in combination of two or more. When using two or more kinds of top coating materials, it is possible to finish the multi-colored appearance of two or more colors by separately coating the top coating materials having different color tones.

Examples will be shown below to further clarify the characteristics of the present invention.

The following undercoat materials 1 to 7 were prepared as undercoat materials.

(Undercoat 1)
Non-aqueous dispersion type acrylic polyol (hydroxyl value 50 KOHmg/g, weight average molecular weight 70,000, glass transition temperature 38°C, solid content 50% by weight, medium: mineral spirit (aniline point 42°C)}, amide wax, solvent naphtha (aniline point) 13° C.) and a main agent containing a silicone antifoaming agent,
A polyisocyanate compound (1,6-diisocyanatohexane derivative, number average functional group number 2.2, solid content 100% by weight), tetraalkoxysilane compound (isobutyl alcohol modified product of tetramethoxysilane condensate), and mineral spirit Mixture with hardener containing (NCO/OH ratio 1.0).
Solid content of resin component in undercoat material: 38% by weight, ratio of compound having reactive silyl group: 3% by weight (SiO ₂ conversion), ratio of mineral spirits in total non-aqueous solvent: 80% by weight, solvent naphtha ratio: 20% by weight, thickener ratio: 1 part by weight to 100 parts by weight of solid content of resin component, pigment volume concentration: 0%.

(Undercoat 2)
A non-aqueous dispersion type acrylic polyol (same as above), an amide wax, a solvent naphtha (same as above), and a main agent containing a silicone antifoaming agent,
A mixture with a curing agent containing a polyisocyanate compound (same as above), a tetraalkoxysilane compound (same as above), and mineral spirits (same as above) (NCO/OH ratio 1.0).
Solid content of resin component in undercoat material: 45% by weight, ratio of compound having reactive silyl group: 3% by weight (converted to SiO ₂ ), mineral spirit ratio in all non-aqueous solvents: 80% by weight, solvent naphtha ratio: 20% by weight, thickener ratio: 1 part by weight to 100 parts by weight of solid content of resin component, pigment volume concentration: 0%.

(Undercoat 3)
Soluble acrylic polyol (hydroxyl value 50 KOHmg/g, weight average molecular weight 20000, glass transition temperature 36°C, solid content 50% by weight, medium: mineral spirit (aniline point 42°C)}, amide wax, solvent naphtha (same as above), And a main agent containing a silicone antifoaming agent,
A mixture with a curing agent containing a polyisocyanate compound (same as above), a tetraalkoxysilane compound (same as above), and mineral spirits (same as above) (NCO/OH ratio 1.0).
Solid content of resin component in undercoat material: 38% by weight, ratio of compound having reactive silyl group: 3% by weight (SiO ₂ conversion), ratio of mineral spirits in total non-aqueous solvent: 80% by weight, solvent naphtha ratio: 20% by weight, thickener ratio: 1 part by weight to 100 parts by weight of solid content of resin component, pigment volume concentration: 0%.

(Undercoat material 4)
A main ingredient containing a soluble acrylic polyol (same as above), an amide wax, a solvent naphtha (same as above), and a silicone antifoaming agent,
A mixture with a curing agent containing a polyisocyanate compound (same as above), a tetraalkoxysilane compound (same as above), and mineral spirits (same as above) (NCO/OH ratio 1.0).
Solid content of resin component in undercoat material: 23% by weight, ratio of compound having reactive silyl group: 3% by weight (SiO ₂ conversion), ratio of mineral spirit in all non-aqueous solvents: 80% by weight, solvent naphtha ratio: 20% by weight, thickener ratio: 1 part by weight to 100 parts by weight of solid content of resin component, pigment volume concentration: 0%.

(Undercoat 5)
A main ingredient containing a soluble acrylic polyol (same as above), heavy calcium carbonate, amide wax, solvent naphtha (same as above), and a silicone antifoaming agent,
A mixture with a curing agent containing a polyisocyanate compound (same as above), a tetraalkoxysilane compound (same as above), and mineral spirits (same as above) (NCO/OH ratio 1.0).
Solid content of resin component in undercoat material: 16% by weight, ratio of compound having reactive silyl group: 3% by weight (converted to SiO ₂ ), mineral spirit ratio in all non-aqueous solvents: 80% by weight, solvent naphtha ratio: 20% by weight, thickener ratio: 1 part by weight to 100 parts by weight of solid content of resin component, pigment volume concentration: 52%.

(Undercoat material 6)
Soluble acrylic silicone resin (weight average molecular weight 60,000, glass transition temperature 35°C, solid content 50% by weight, medium: mineral spirit (aniline point 42°C)}, amide wax, mineral spirit (same as above), and silicone-based defoaming A main agent containing an agent,
Mixtures with organotin compounds and hardeners containing mineral spirits (Id.).
Solid content of resin component in undercoat material: 40% by weight, ratio of compound having reactive silyl group: 1% by weight (SiO ₂ conversion), ratio of mineral spirit in all non-aqueous solvent: 100% by weight, ratio of thickener : 1 part by weight to 100 parts by weight of solid content of resin component, pigment volume concentration: 0%.

(Undercoat 7)
Soluble acrylic silicone resin (same as above), amide wax, mineral spirits (same as above), and a main agent containing a silicone antifoaming agent,
Mixtures with organotin compounds and hardeners containing mineral spirits (Id.).
Solid content of resin component in undercoat material: 22% by weight, ratio of compound having reactive silyl group: 1% by weight (SiO ₂ conversion), ratio of mineral spirit in all non-aqueous solvent: 100% by weight, ratio of thickener : 1 part by weight to 100 parts by weight of solid content of resin component, pigment volume concentration: 0%.

(Test method)
As an existing wall surface, a ceramic siding boat that has deteriorated due to outdoor exposure (convex parts and concave parts (joints) with tile joints on the surface and irregular irregular patterns on the convex parts) is an inorganic clear film as the outermost surface coating film. Prepared). The undercoat material is spray-coated on the entire surface of the existing wall surface at a coating amount of 0.1 kg/m ² , dried for 3 hours, and then the top coating material (pale brown acrylic silicone resin coating) is coated at 0.2 kg/m ² . Test specimens were prepared by spray painting in No. ^{2 and} drying and curing for 7 days. The coating and curing steps were all performed under standard conditions (temperature 23°C, relative humidity 50%).

(Evaluation methods)
-Finishability The finished appearance of the test piece produced by the above method was visually confirmed. In the evaluation, the one in which the concavo-convex pattern on the existing wall surface was utilized was evaluated as "○", and the other one was evaluated as "x".

-Adhesiveness With respect to the test body produced by the above method, a crosscut was put on the coating film at each site of the uneven pattern with a cutter knife, and a tape was attached to the crosscut portion to remove the adhesiveness, and thus the adhesiveness was evaluated. The evaluation was “A” when no peeling was observed at any part, “B” when it was almost good but partially peeled, and “C” when a large amount of peeling was observed. I went as.

(Test results)
Table 1 shows the undercoat material used in the above test and the test results. In Examples 1 to 4, almost good results were obtained.

Claims (3)

A method of applying an undercoat material and an overcoat material in order to an existing wall surface that has deteriorated over time,
The existing wall surface has an uneven pattern on the surface, and is provided with an existing coating,
The undercoat material contains a non-aqueous solvent (A), a resin component (B), and a thickener (C),
The non-aqueous solvent (A) contains a non-aqueous solvent having an aniline point of 12 to 70°C,
The resin component (B) is composed of one or more compounds, and at least one of the compounds is a compound having a reactive silyl group,
The solid content of the resin component (B) is 25 to 75% by weight in the undercoat material,
The undercoat material has a pigment volume concentration of less than 30%, which is a makeup method. The resin component (B) is composed of one or more compounds,
The cosmetic method according to claim 1, wherein at least one of the compounds is a resin having a weight average molecular weight of 10,000 to 150,000. The makeup method according to claim 1 or 2, wherein the existing wall surface has a concavo-convex pattern on the surface and is constituted by a plurality of plate-shaped wall materials provided with an existing coating.