JP2003001749A - Metal siding structure having high design effect - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal siding structure having high design effect having no environmental pollution problem and excellent in weatherability. SOLUTION: The metal siding structure having high design effect is constituted by coating the surfaces of the projected parts of a PCM material lined with a PCM steel sheet subjected to emboss processing with an aqueous color base paint containing a core/shell type silicone modified acryl emulsion, which is a core/shell type acrylic emulsion and prepared by forming a grafted and crosslinked structure of polysiloxane to an acrylic skeleton, to form a color base coating film layer and coating the surface of the obtained empossed pattern with a top clear paint if necessary to form a top clear layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a highly-designable metal siding structure, and more specifically, there is no environmental problem,
The present invention relates to a highly designable metal siding structure having excellent interlayer adhesion, weather resistance, durability and stain resistance.

[0002]

2. Description of the Related Art Conventionally, as a highly-designed metal siding structure, for example, a primer or sealer is applied to the surface of a PCM material lined with a deeply embossed PCM steel sheet to obtain an embossed pattern. A convex base coating film layer is formed on the convex portion, and if necessary, sand coating, clear coating for sand holding, drying, formation of a shaking pattern by gravure offset printing, top coat clear coating, drying, etc. What is obtained by sequentially performing steps is known.

In recent years, due to deep embossing,
Attempts have been made to impart high designability, and as the convex base coating and top clear coating, for example, acrylic urethane coating and acrylic melamine coating have been used.

However, since the conventional high design metal siding structure has insufficient weather resistance, there is no environmental problem, and a high design metal siding structure with improved weather resistance is demanded.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention have earnestly studied to obtain a highly designable metal siding structure with high weather resistance and no environmental problems, and as a result, the inventors have found that it has excellent adhesion to PCM materials. By using a specific water-based pigmented base paint and optionally a top clear, it was found that a highly designed metal siding structure with excellent weather resistance and the like can be obtained without using a solvent type sealer. The invention was completed.

That is, according to the present invention, a core-shell type acrylic emulsion, which is a core-shell type acrylic emulsion, is formed on the surface of a convex portion of a PCM material which is lined with an embossed PCM steel sheet, and which has a graft and cross-linking structure of polysiloxane to an acrylic skeleton. The core-shell type silicone-modified acrylic emulsion prepared by the formation and a water-based colored base coating material containing a silane coupling agent are roll-coated to form a colored base coating film layer, and if necessary, the top surface of the obtained embossed pattern is topped. Provided is a high design metal siding structure in which a clear is applied to form a top clear layer.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION PC used in the present invention
As the M material, for example, a metal plate such as aluminum, steel, aluminum 55% alloy galvanium, 5% alloy galfan, etc., containing isophthalic acid type polyester / melamine, vinylidene fluoride / acrylic / melamine / bisphenol A type epoxy containing, Alternatively, a PCM steel sheet obtained by pre-coating a resin composition containing terephthalic acid type polyester / melamine / bisphenol A type epoxy is embossed into brick tone, tile tone, wood grain tone, stone tone tone, etc. to impart soundproofness and heat insulation. For this purpose, it is lined with urethane foam, gypsum board, etc., and molded as a predetermined outer wall board.

[0008] In general, metal siding is inexpensive and lightweight, has good workability, is superior in frost damage to ceramic siding, and can be used mainly for reforming and cold districts.

As the top clear used as necessary in the present invention, a conventionally known aqueous or organic solvent type coating composition having excellent weather resistance, for example, a cured or uncured type coating composition, water-soluble, water-dispersed Alternatively, an emulsion type and an anion, cation or nonion type can be used. Specifically, as the paint type, for example, alkyd resin type, polyester resin type, silicone resin type, fluororesin type, epoxy resin type, urethane resin type,
Acrylic resin-based resins and resins using these modified resins as base resins are mentioned. Of these, silicone-based paints are preferable. Further, the following core-shell type silicone-modified acrylic emulsion and the following curable silicone-based paint are preferable. Further, it is most preferable from the viewpoint of adhesion that the core-shell type silicone-modified acrylic emulsion is blended with the silane coupling agent described below, that is, the same resin composition as that used in the aqueous colored base coating composition described below is used. .

As the curable silicone-based coating material, a conventionally known type, for example, an organic solvent-based coating material of a heat- and room-temperature-curable silicone resin can be used without particular limitation.
As this, it is particularly preferable to use a resin containing 50 mol% or more of a tetrafunctional silicon structural unit or a trifunctional silicon structural unit in the resin. Further, as the functional group used for curing, for example, a hydrolyzable group directly bonded to a silicon atom (for example, a lower (about 1 to 3 carbon atoms) alkoxy group, an acyl group, an acetoxy group, a butanoxime group, etc.), A hydroxysilyl group and the like are included. Examples of the hydrolyzable group and hydroxysilyl group in the resin include organic metal compounds (metal chlorides, metal alkoxides, metal chelates, and the like. Examples of the metal include Al, Zr, Ti, etc.), and the like. It can be cured by reaction with epoxy groups.

In addition to the above functional groups, an epoxy group,
If necessary, functional groups other than the above, such as unsaturated groups, can also be included. These functional groups include, for example, epoxy groups such as cationic polymerization catalysts (sulfonium salts, ammonium salts, phosphonium salts, oxonium salts, etc.), and trade names include, for example, San-Aid SI-100.
L (manufactured by Sanshin Kagaku Co., Ltd.), the above-mentioned hydrolyzable silyl group, hydroxysilyl group, a reaction by a combination with an organometallic compound, and the like, an unsaturated group ((meth) acryloyl group,
For example, a vinyl group) can be reacted with a peroxide catalyst.

The tetrafunctional silicon structural unit is a silicon structural unit (Q unit) represented by the general formula SiZ4. Z in the formula
Represents a hydrolyzable group capable of forming a hydroxysilyl group and / or finally a silanol group or condensing with another silicon atom to form a siloxane bond.

Examples of the compound having a tetrafunctional silicon structural unit include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, dimethoxydiethoxysilane and triacetoxysilane. Such a compound can also be used as a low condensate (for example, a dimer to a dimer, preferably a dimer to a pentamer). When such a low-condensation product having more than four functional groups is used, it is treated as a Q unit in the present invention.

The trifunctional silicon structural unit has the general formula RSiZ3
The silicon structural unit (T unit) represented by (Z has the same meaning as described above) forms a hydroxysilyl group and / or finally a silanol group or is condensed with another silicon atom to form a siloxane bond. It contains three hydrolyzable groups capable of forming R is an organic substituent, and is a hydrocarbon group (eg, methyl group, ethyl group, propyl group,
Butyl group, phenyl group, etc.) and other organic functional groups (γ-glycidoxypropyl group, β- (3,4-epoxycyclohexyl) -ethyl group, 5,6-epoxyhexyl group,
9,10-epoxydecyl group, γ-methacryloxypropyl group, γ-methacryloxymethyl group, γ-acryloxypropyl group, γ-acryloxymethyl group, vinyl group and the like).

Examples thereof include trimethoxymethylsilane, trimethoxyethylsilane, trimethoxypropylsilane, trimethoxybutylsilane, trimethoxyphenylsilane, triethoxymethylsilane, triethoxyethylsilane, triethoxybutylsilane,
Triethoxyphenylsilane, tripropoxymethylsilane, tripropoxypropylsilane, tripropoxyphenylsilane, tryptoxyphenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (methoxyethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane , 2-styrylethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane and the like.

The content of the Q and T units is in the range of 50 mol% or more (relative to total silicon atoms), preferably 60 mol% or more, in the total amount of the Q and T units in the silicone compound. Further, the ratio of Q unit / T unit mol% is 100 /
The range of 0 to 90/10 is preferable, and the range of 100/0 to 30/70 is preferable. If the content of Q and T units in the silicon compound is less than 50 mol%, the amount of other organic resin components increases and the durability of the coating film deteriorates.

In addition to the components described above, as the remaining components, a silicon structural unit (D unit) represented by a bifunctional silicon structural unit (general formula R2SiZ2) (Z represents the same meaning as described above) and a monofunctional silicon structural unit ( A silicon structural unit (M is represented by the general formula R3SiZ2) (Z has the same meaning as above).
Units).

Examples of the above include methoxytrimethylsilane, methoxytriethylsilane, methoxymethyldiethylsilane, ethoxytrimethylsilane,
Monoalkoxysilanes such as ethoxytriethylsilane, ethoxytriphenylsilane, propoxytrimethylsilane, propoxytripropylsilane, butoxytributylsilane, phenoxytriphenylsilane, dimethoxydimethylsilane, dimethoxydiethylsilane, dimethoxydiphenylsilane, diethoxydimethylsilane, di Ethoxydiethylsilane, diethoxydiphenylsilane, dipropoxydimethylsilane, dipropoxydiethylsilane, dipropoxydipropylsilane, dipropoxydiphenylsilane, dibutoxydimethylsilane, dibutoxydiethylsilane, dibutoxydibutylsilane, dibutoxydiphenylsilane, etc. Dialkoxy silanes. Examples of the curable type include isocyanate curable type, oxidative polymerization curable type, active energy ray curable type, and hydrolytic condensation reaction type.

As a water-based pigmented base coating used in the present invention, a core-shell type acrylic emulsion for improving weather resistance, stain resistance and adhesion to PCM materials, which is a polysiloxane to the acrylic skeleton of polysiloxane. Those containing a core-shell type silicone-modified acrylic emulsion by forming a graft and crosslinked structure can be preferably used.

The core-shell type emulsion is an aqueous dispersion of polymer particles, and the polymer particles have a core portion (core portion).
And a coating portion (shell portion) covering the periphery thereof, and the compositions of these two portions are different from each other, and in the present invention, they are distinguished based on Tg. Such a core-shell type emulsion can be prepared by a seed polymerization method known per se.

That is, as an aqueous coating composition containing a core-shell type acrylic emulsion, (A) core
A water-based coating composition containing a shell-type emulsion and optionally (B) a film-forming aid, wherein the glass transition temperature of the core portion of the component (A) is -20 to 50 ° C, and the glass transition temperature of the shell portion. Is 51 to 100 ° C., the total glass transition temperature of both parts is 5 to 60 ° C., and the component (B) can be an alcohol component having a boiling point of 100 to 270 ° C.

Specifically, a monomer mixture (i) comprising a) a carboxyl group-containing unsaturated monomer and b) an unsaturated monomer (excluding a) is emulsion polymerized in water. Forming a core portion (seed polymerized latex), and then adding c) (meth) acrylic acid ester, d) carboxyl group-containing unsaturated monomer and e) unsaturated monomer (however, c), A core-shell type emulsion is obtained by adding a monomer mixture (ii) excluding d) and performing emulsion polymerization to form a shell portion.

A) The carboxyl group-containing unsaturated monomer is
It is a compound having at least one carboxyl group and at least one polymerizable double bond in one molecule, and examples thereof include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, and maleic anhydride.

The unsaturated monomer b) is a compound having at least one polymerizable double bond in one molecule and does not include the above a). For example, an esterified product of acrylic acid or methacrylic acid and a monoalcohol having 1 to 20 carbon atoms; an aromatic monomer such as styrene and vinyltoluene, a vinyl ester such as vinyl acetate, vinyl propionate and vinyl versatate; acrylonitrile, Vinyl cyanide such as methacrylonitrile; vinyl halide such as vinyl chloride, vinylidene chloride, vinyl fluoride; acrylamide, methacrylamide, diacetone acrylamide, diacetone methacrylamide, glycidyl acrylate, glycidyl methacrylate, hydroxyethyl acrylate, hydroxyethyl Methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, N-methylol acrylamide, N-butoxymethyl acrylamide, methacryl Le acid acidphosphoxyethyl ethyl, acrylate, 3-chloro-2-acid phosphoxy propyl, methyl propane sulfonic acid acrylamide, divinyl benzene, allyl acrylate,
Allyl methacrylate, (poly) oxyethylene diacrylate, (poly) oxyethylene dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, allyl sulfosuccinic acid, styrene sulfonic acid, etc. Functional group-containing monomers, vinyl silicon monomers and the like are included.

Examples of the vinyl silicon monomer include vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (methoxyethoxy) silane and γ-.
(Meth) acryloyloxypropyltrimethoxysilane, 2-styrylethyltrimethoxysilane, vinyltrichlorosilane, γ- (meth) acryloyloxypropyltriacetoxysilane, γ- (meth) acryloyloxypropyltrihydroxysilane, γ- (meth ) Hydroxysilane such as acryloyloxypropylmethylhydroxysilane and / or a vinyl monomer containing a hydrolyzable silane group.

The ratio of the monomer a) to the monomer b) in the monomer mixture (i) is not particularly limited, but the monomer a) has a ratio of 0. 05-50
%, Especially 0.5-5%, monomer b) is 99.95-50
%, Especially in the range of 99.5 to 95% is suitable.

The core part can be prepared by polymerizing the monomer mixture (i) in water by a usual emulsion polymerization method. As the polymerization catalyst, water-soluble or oil-soluble potassium persulfate, ammonium persulfate, sodium persulfate, hydrogen peroxide, t-butyl hydroperoxide,
t-butyl peroxybenzoate, 2,2-azobisisobutyronitrile, 2,2-azobis (2-amidinopropane) hydrochloride, 2,2-azobis (2,4-dimethylvaleronitrile) and the like. ,
Of these, water-soluble ones are particularly preferable. The amount used is preferably 0.1 to 1% by weight of the monomer mixture (i). Further, for the purpose of accelerating the polymerization rate or low temperature polymerization, a reducing agent such as sodium bisulfite, ferrous chloride, ascorbate, Rongalit or the like can be used in combination. Furthermore, known polymerization regulators and surfactants can be used as necessary.

Next, in the aqueous dispersion of the core portion thus obtained, c) (meth) acrylic acid ester, d) a carboxyl group-containing unsaturated monomer and e) an unsaturated monomer (however, c) , D) are added and emulsion polymerization is carried out to form a shell portion, whereby a core / shell type emulsion is obtained.

Examples of the c) (meth) acrylic ester and d) the carboxyl group-containing unsaturated monomer are those exemplified in the monomer a) and the monomer b) of the above-mentioned monomer mixture (i). Can be applied. Further, the monomer e) is a compound having at least one polymerizable double bond in one molecule, and excluding c) (meth) acrylic acid ester and d) a carboxyl group-containing unsaturated monomer. In addition, those exemplified for the monomer b) of the monomer mixture (i) can be applied.

The ratio of these monomers in the monomer mixture (ii) is not particularly limited, but the monomer c) is 15 to 100% based on the total weight of these monomers. Suitably, d) is in the range of 0 to 15% and monomer e) is in the range of 0 to 70%. In the emulsion polymerization for forming the shell portion, the above-mentioned polymerization catalyst, reducing agent, polymerization regulator, surfactant and the like can be used if necessary.

In the core / shell type emulsion (A) used in the present invention, the composition ratio of the monomer mixture (i) and the monomer mixture (ii) is not particularly limited, but is based on the total weight of both components. In addition, the monomer mixture (i) is 5 to 80%,
Particularly, 10 to 60%, 95 to 20 for the monomer mixture (ii).
%, Especially in the range of 90-40% is suitable.

Particularly, in the present invention, (A) the core / shell type emulsion has a Tg of −20 to 50 ° C., a Tg of the shell of 51 to 100 ° C., and a total Tg of both portions.
Is preferably in the range of 5 to 60 ° C.

These Tg's can be calculated by the following equations.

1 / Tg (° K) = (W1 / T1) + (W2
/T2)+...Tg(° C.) = Tg (° K) -273 In the formula, W1, W2 ... Are the respective weight percentages of the monomers used in the copolymerization, and T1, T2 ,. Represents the Tg (° K) of the homopolymer of In addition, T1, T2, ...
Is a Polymer Hand Book (Scond
Edition, J.M. Brandup E. H. Im
It is the value according to the "Mergut" edition.

Then, the total Tg of the core part and the shell part is
It is calculated by (weight% of core part × Tg of core part) + (weight% of shell part × Tg of shell part).

In the core / shell type emulsion (A), when the Tg of the core portion is lower than -20 ° C, the formed coating film tends to be blocked, while when it is higher than 50 ° C, the film-forming property and the low temperature physical properties (freeze-thaw test). ) And so on.
When the Tg of the shell part is 50 ° C. or less, the formed coating film tends to be blocked, and when the total Tg of both parts is 60 ° C. or more, the film forming property and the low temperature physical property (freezing and thawing test) are deteriorated. Absent.

As the film-forming aid (B), one or more selected from alcohol components having a boiling point (BP) of 100 to 270 ° C. can be used. As the alcohol component, specifically, ethylene glycol monobutyl ether (butyl cellosolve, molecular weight 118, BP171
° C), diethylene glycol monobutyl ether (butyl carbitol, molecular weight 162, BP230 ° C), diethylene glycol monobutyl ether acetate (butyl carbitol acetate, molecular weight 206, BP246)
℃), propylene glycol monomethyl ether (molecular weight 90, BP 120 ℃) and the like. further,
_{(CH 3) 2 CHCOOCH 2 C} (CH 3) 2 C (OH)
2,2,4-trimethyl 1,3-pentanediol monoisobutyrate (texanol, molecular weight 216, BP 248 ° C.) represented by HCH (CH ₃ ) ₂ is also effective as the film-forming auxiliary (B).

When the boiling point of the alcohol component is lower than 100 ° C., the coatability (film forming property) of the coating film is not sufficient, and when the boiling point is higher than 270 ° C., it tends to remain in the coating film, such as water resistance and moisture resistance. Is reduced, which is not preferable.

In the present invention, the content of the film-forming auxiliary (B) is not particularly limited, but is 0.1-10 per 100 parts by weight of the resin solid content of the (A) core-shell type emulsion.
It is in the range of parts by weight, preferably 0.3 to 4 parts by weight, more preferably 0.5 to 2 parts by weight.

In the present invention, it is preferable that the above-mentioned water-based colored base coating material has a dry film thickness of 5 to 5 on the convex surface of the PCM material.
The base coating film layer is formed by roll coating so that the coating amount is 100 g / m ^2, and an embossed pattern is obtained. More preferably, cyclohexyl methacrylate can be contained as a radically polymerizable monomer component constituting the emulsion in an amount of 5 to 50 parts by weight per 100 parts by weight of the solid content of the emulsion. When the content is less than 5 parts by weight, performances such as hot water resistance and boiling water resistance are deteriorated, which is not preferable, and when it exceeds 50 parts by weight, the coating film becomes brittle.

Aqueous colored base paint containing a core / shell type acrylic emulsion manufactured by Asahi Kasei Corporation, for example, resin trade name X-508 Kai (core / shell type, resin composition MMA / n-BA, core Tg20). ℃, shell Tg60 ℃), the same resin trade name B-2500 (core
Shell type, resin composition MMA / n-BA / CHMA, UV
A and HALS included, CHMA 20% by weight, core Tg
11 ° C., shell Tg 60 ° C.), and company latex product names X-1595-19B, X-19B-CR1, same CR2, same CR0, same MW2, same TG1, same TG2, same A2, same 11, same CS1, same. Examples include OH1.

The air-shell type silicone-modified acrylic emulsion used in the aqueous colored base coating composition of the present invention has a glass transition temperature of the core portion of -20 to 50 ° C., a glass transition temperature of the shell portion of 51 to 100 ° C., and both portions. Glass transition temperature of 5 to 60 ° C., emulsion particle size of 50 to
It is possible to use one having a thickness of 300 nm and a silicon content of 10 to 40% by weight.

As the water-based coloring base paint, one containing a core / shell type silicone-modified acrylic emulsion manufactured by Asahi Kasei Corporation, for example, latex product name G-620 (core / shell type, resin composition Ac / S manufactured by the same company).
i (Si 20 wt%), UVA and HALS included, C
HMA 30% by weight, core Tg 48 ° C, shell TgMFT
C), the same latex product name G-655 (core / shell type, resin composition Ac / Si (Si 20% by weight), CHMA
10 wt%, core Tg 50 ° C, shell TgMFT ° C),
The latex trade name G-659 (core / shell type, resin composition Ac / Si (Si 20% by weight), CHMA 10% by weight) and the like can be mentioned.

As the silane coupling agent to be added to the water-based coloring base coating material, conventionally known ones can be used, but a silane coupling agent containing an epoxy group or an amino group is particularly preferable. Examples of preferable silane coupling agents include amino group-containing silane compounds; N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, and γ-amino. Propyltrimethoxysilane, γ-N- (2-aminoethyl)
Aminopropyltrimethoxysilane, p- (N, N-dimethylamino) phenyltriethoxysilane, N-
(2-Aminoethyl) aminomethylphenethyltrimethoxysilane, 3-aminopropylmethyldiethoxysilane, γ-N, N-bis (2-hydroxyethyl) aminopropyltriethoxysilane, bis [3- (triethoxysilyl) Propyl] amine, γ-N, N-diethylaminopropyltrimethoxysilane, N, N-dimethylaminophenyltriethoxysilane: epoxy group-containing silane compound; β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane and the like can be mentioned. Among these, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, β- (3,4-epoxy) Cyclohexyl) ethyltriethoxysilane is preferred.

The blending ratio of the silane coupling agent is 0.001 to 5 parts by weight, and particularly 0.001 part by weight based on 100 parts by weight of the solid content of the core-shell type silicone modified acrylic emulsion.
The range of 01 to 3 parts by weight is preferable. When the amount of the silane coupling agent is less than 0.001 part by weight, the adhesiveness is deteriorated, while when it exceeds 5 parts by weight, the storage stability of the paint, the appearance of the coating film, etc. are deteriorated, which is not preferable.

In the present invention, an aqueous or organic solvent type top clear can be applied to the surface of the embossed pattern thus obtained to form a top clear layer.

As the above-mentioned water-based top clear, any conventionally known one having excellent weather resistance can be used without particular limitation.
Preferably the same as used in the pigmented base paint,
For example, a core / shell type emulsion, particularly a core / shell type silicone-modified acrylic emulsion can be used.

The above-mentioned top clear is preferably used as a matting clear containing a matting agent, and examples of the matting agent include silica and polyethylene oxide. From the viewpoint of adhesion, precipitation resistance, etc., polyethylene oxide is preferred. For example, SN-OX (oxidized polyethylene matting agent manufactured by San Nobuco) is particularly preferable.

If necessary, the top clear may contain, for example, a film forming aid, a defoaming agent, a surface conditioner and a thickener, in addition to the matting agent.

The high design metal siding structure of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a partial cross-sectional view for explaining an example of the highly-designable metal siding structure of the present invention. Figure 1
, 1 is an aluminum laminate for backing, 2 is a foamed urethane foam for backing, 3
Is an embossed PCM steel sheet, 4 is a base coating layer, 5 is a top clear layer, 6 is a convex portion by embossing, and 7 is a concave portion by embossing. In FIG. 1, a PC lined with aluminum laminate 1 and urethane foam 2 and embossed
The base coating film layer 3 is formed on the surface of the convex portion of the PCM material composed of the M steel plate 3, and the top clear layer 5 is formed on the surface of the obtained embossed pattern.

[0052]

The present invention will be described in more detail with reference to the following examples.

Example 1 A test PCM material lined with, for example, a tiled PCM steel sheet that has been deeply embossed and embossed (for example, precoated with a resin composition of an isophthalic acid type polyester / melamine resin) with a urethane foam and an aluminum laminate. (60
cm60 × 60 cm), the following G620 solid content 1
00 g, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane 0.2 g, white pigment paste (titanium dioxide 100 g / pigment dispersion resin 5 g), solid content 10
The water-based colored base coating material obtained by mixing 0 g was roll-coated so that the dry film thickness was 50 g / m ² (solid content conversion) to form a colored base coating film layer to obtain an embossed pattern.

Example 2 The surface of the embossed pattern obtained in Example 1 was spray coated with the following matte top clear so that the dry film thickness was 30 g / m ² (solid content conversion). A test metal siding structure was obtained. The results of the weather resistance test are shown in Table 1.

Preparation of Matte Top Clear Matte top clear was prepared by the following formulation. 48% by weight (solid content) G-620 (base resin) (Note 1) 217 g polyethylene oxide (matting agent) 18 g β- (3,4-epoxycyclohexyl) ethyltriethoxysilane 0.2 g solid content (NV ) 42.0 wt% MFT 0 ° C.> (Note 1) Core / shell type silicone modified acrylic emulsion-containing latex, trade name, resin composition Ac / Si (Si 20 wt%), UVA and H
ALS content, CHMA 30% by weight, core Tg 15 ° C., shell Tg 60 ° C., total Tg 48 ° C., particle size 130 nm.

Comparative Example 1 Acrylic urethane resin colored paint was applied to the surface of the convex portion on the surface of the PCM material of Example 1 and cured at 80 ° C. for 2 minutes to obtain a test metal siding structure of Comparative Example 1. .
The results of the weather resistance test are shown in Table 1.

Example 3 A mixture of 62 g (0.3 mol) of tetraethoxysilane, 125 g (0.7 mol) of methyltrimethoxysilane and 187 g of ethyl alcohol was heated to 80 ° C. and 0.2 N was added.
-Add 30 g of hydrochloric acid and react at 80 ° C for 10 hours.
Then, 30 g of triethylamine was added to this reaction product to a pH of 7 or more to cause a condensation reaction at 80 ° C. for 2 hours, 100 g of benzene was added, and the solvent was removed until the solid content was 40% by weight. Mol%, 3
A functional silicon resin (70 mol%) was obtained.

An experiment similar to that of Example 2 was also conducted, except that the obtained silicon resin was used in place of the G-620 used in the top clear. The results obtained are shown in Table 1.

Example 4 An experiment similar to that of Example 2 was conducted, except that the G-655 used in the water-based pigmented base paint was replaced with the G-655. The results obtained are shown in Table 1.

Example 5 An experiment similar to that of Example 2 was performed, except that the G-659 was used instead of the G-620 used in the water-based pigmented base paint. The results obtained are shown in Table 1.

Example 6 Instead of the β- (3,4-epoxycyclohexyl) ethyltriethoxysilane used in the aqueous pigmented base coating,
The same experiment as in Example 2 was conducted except that N-β (aminoethyl) γ-aminopropyltrimethoxysilane was used. The results obtained are shown in Table 1.

Example 7 Instead of the β- (3,4-epoxycyclohexyl) ethyltriethoxysilane used in the aqueous pigmented base coating,
The same experiment as in Example 2 was performed except that N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane was used. The results obtained are shown in Table 1.

Example 8 Instead of the β- (3,4-epoxycyclohexyl) ethyltriethoxysilane used in the aqueous pigmented base coating,
The same experiment as in Example 2 was conducted except that γ-aminopropyltrimethoxysilane was used. The results obtained are shown in Table 1.

[0064]

[Table 1]

Test Method Smoothness: The smoothness of the surface was visually evaluated. ○ is good, △
Is poor, and x is significantly poor. Adhesion: JIS K-5400 8, 5, 2 (199
0) Substrate-Based on the tape method, 100 1 mm × 1 mm squares were prepared, and the degree of peeling of the squares when the tape was adhered and peeled off was tested. The case where there was no peeling was rated as ◯. Those with peeling were marked with x.

Adhesion after boiling water: The above adhesion was examined after immersion in boiling water for 10 hours.

Weather resistance: Weather meter (manufactured by Suga Test Instruments Co., Ltd., due cycle, irradiation 60 minutes / dark 60 minutes,
An accelerated weather resistance test was performed for 240 hours at a black panel temperature of 63 ° C., and the gloss retention rate (unit:%) and the appearance were visually observed. Appearance: ○: Good △: Inferior ×: Remarkably inferior

[0068]

EFFECTS OF THE INVENTION A highly-designable metal siding structure having excellent weather resistance can be obtained. By using an aqueous base coating having excellent adhesion to the PCM material and the top clear layer, the sealer layer, particularly the solvent type sealer layer can be omitted. The use of water-based paint eliminates the problem of environmental pollution.

[0069]

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view for explaining an example of a high design metal siding structure of the present invention.

[Explanation of symbols]

1 Aluminum laminate 2 urethane foam 3 PCM steel plate 4 Base coating layer 5 Top clear layer 6 Embossed protrusion 7 Embossed recess

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) E04F 13/12 E04F 13/12 C F term (reference) 2E110 AA26 AA57 AB04 AB22 BA02 BA12 BB04 BB23 GA33W GB02W GB44W 4D075 AC22 BB06X CB01 DA06 DA36 DB02 DC02 EA13 EA43 EB43 4F100 AB03A AH06B AH06H AK01C AK25B AK25C AK25J AK52B AK52C AK52J AL04B AL04C AL06B BA02 BA03 BA07 CA02 CC00B CC00C DD01A GB07 HB21A JA05B JA20B JK06 JL00 JL06 JL09 JM01C JM01J JN01C JN26C YY00B

Claims (9)

[Claims] 1. A core-shell type acrylic emulsion, comprising a core-shell type acrylic emulsion, which is formed by forming a graft and cross-linking structure on the acrylic skeleton of polysiloxane on the convex surface of a PCM material lined with an embossed PCM steel sheet. An aqueous colored base coating material containing a shell type silicone modified acrylic emulsion and a silane coupling agent is roll-coated to form a colored base coating film layer, and if necessary, top clear is applied to the surface of the embossed pattern obtained. Highly designable metal siding structure with a top clear layer. 2. The aqueous colored base coating composition has a glass transition temperature of the core portion of −20 to 50 ° C., a glass transition temperature of the shell portion of 51 to 100 ° C., and a total glass transition temperature of both portions is 5.
The highly designable metal siding structure according to claim 1, which contains a core-shell type hydroxyl group-containing silicone modified acrylic emulsion at -60 ° C. 3. The composition according to claim 2, wherein the content of cyclohexyl methacrylate as a radical-polymerizable monomer component constituting the emulsion according to claim 2 is in the range of 5 to 50 parts by weight per 100 parts by weight of the solid content of the emulsion. Designed metal siding structure. 4. The core-shell type silicone-modified acrylic emulsion has an emulsion particle size of 50 to 300 n.
The highly-designable metal siding structure according to claim 1, which is m. 5. The content of silicon monomer as a radically polymerizable monomer component constituting the emulsion is 1 to 1
The high design metal siding structure according to claim 1, which is 40% by weight. 6. The highly-designable metal siding structure according to claim 1, wherein the silane coupling agent is a silane coupling agent containing an epoxy group or an amino group. 7. The highly-designable metal siding structure according to claim 1, wherein the top clear is an organic solvent-based or water-based silicone paint. 8. The highly-designable metal siding structure according to claim 1, wherein the top clear is a core-shell type silicone-modified acrylic emulsion. 9. The highly-designable metal siding structure according to claim 1, wherein the top clear is a matting clear containing a matting agent.