JP3430429B2 - Building materials - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metallic building material which is metallically coated with an inorganic coating agent.

[0002]

2. Description of the Related Art When a building material such as a wall material is made of a metal-based material such as iron, aluminum or stainless steel, the surface of the metal-based material has a defect in corrosion resistance and scratch resistance. Painting has been carried out for protection purposes. In this way, when paint is applied to the surface of a metal-based material to create a building material, it is common to use an organic paint as the paint, and by adding a pearl pigment to the organic paint, metallic paint can be applied. It is done.

However, since organic paints do not provide sufficient performance in terms of weather resistance and corrosion resistance, coating with an inorganic coating agent containing an alkali metal silicate as a main component is also carried out. Has been.

[0004]

However, the inorganic coating agent containing an alkali metal silicate as a main component requires a high baking temperature of 200 ° C. or higher, and causes the white flower phenomenon in a long-term practical test. However, it was impossible to obtain sufficient weather resistance and corrosion resistance. The present invention has been made in view of the above points, and provides a building material that can be coated by baking at low temperature, and has an excellent metallic appearance, as well as excellent weather resistance and corrosion resistance. That is the purpose.

[0005]

DISCLOSURE OF THE INVENTION The present invention relates to a building material formed by applying a base coat, a middle coat, and a top coat on the basis of a metallic material, and a general formula (R ¹ ) _m Si (OR ² ) _4-m (I) (In the formula, each R ¹ represents a methyl group, an ethyl group or a phenyl group, and each R ² represents an alkyl group having 1 to 8 carbon atoms.
m is 0, 1 or 2. ) A silicon alkoxide-based coating agent containing a silicon compound and / or a partial hydrolyzate thereof as a main component, and a pigment and a pearl pigment in an amount of 5 to 90% by weight based on the total amount of the pigment and the pearl pigment. It is characterized by using the thing.

The present invention is also based on a metallic material,
In a building material formed by applying an undercoat, an intermediate coat, and an overcoat, as a coating agent for the intermediate coat, (a) a general formula (R ³ ) _n SiX _4-n (II) (wherein R ³ is each Substituted or unsubstituted C1-8
Represents a monovalent hydrocarbon group, and X represents a hydrolyzable group.
n is an integer of 0-3. ) A hydrolyzable organosilane represented by the formula (4) is partially hydrolyzed in colloidal silica dispersed in an organic solvent and / or water, and a silica-dispersed oligomer solution of organosilane (b) average composition formula R ⁴ _d Si (OH) _e O _{(4-de) / 2} (III) (In the formula, R ⁴ is each a substituted or unsubstituted C 1 to C 8
Represents a monovalent hydrocarbon group, and d and e are each 0.
It is a number that satisfies the relationship of 2 ≦ d ≦ 2.0, 0.0001 ≦ e ≦ 3, and d + e <4. ) A polyorganosiloxane containing a silanol group in the molecule, and (c) a curing catalyst, a silicon alkoxide coating containing three components (a), (b) and (c) as essential components. 5 to 90 based on the total amount of the pigment and the pigment in the agent
It is characterized by using a mixture containing a pearl pigment in an amount of% by weight.

The present invention further relates to a building material formed by applying a base coat, a middle coat and a top coat on the basis of a metallic material, and as a coating agent for the middle coat, it has the general formula (R ¹ ) _m Si (OR ² ) _4-m ... (I) (in the formula, R ¹ each represent a methyl group, an ethyl group or a phenyl group, R ² each represents an alkyl group having 1 to 8 carbon atoms.
m is 0, 1 or 2. ) A silicon alkoxide-based coating agent containing a silicon compound represented by (4) and / or a partial hydrolyzate thereof as a main component is used, and a pearl pigment having a solid content of 1 to 50% by weight is blended as a top coating agent. It is characterized by that.

The present invention further relates to a building material, which is formed by applying a base coat, a middle coat and a top coat on the basis of a metallic material, as a coating agent for the middle coat, comprising (a) a general formula (R ³ ) _n SiX _4-n ... (II) (In the formula, R ³ is each a substituted or unsubstituted C 1 to C 8
Represents a monovalent hydrocarbon group, and X represents a hydrolyzable group.
n is an integer of 0-3. ) A hydrolyzable organosilane represented by the formula (4) is partially hydrolyzed in colloidal silica dispersed in an organic solvent and / or water, and a silica-dispersed oligomer solution of organosilane (b) average composition formula R ⁴ _d Si (OH) _e O _{(4-de) / 2} (III) (In the formula, R ⁴ is each a substituted or unsubstituted C 1 to C 8
Represents a monovalent hydrocarbon group, and d and e are each 0.
It is a number that satisfies the relationship of 2 ≦ d ≦ 2.0, 0.0001 ≦ e ≦ 3, and d + e <4. ) A polyorganosiloxane containing a silanol group in the molecule, and (c) a curing catalyst, a silicon alkoxide coating containing three components (a), (b) and (c) as essential components. It is characterized in that a pearl pigment having a solid content of 1 to 50% by weight is blended as a top coating agent.

The present invention will be described in detail below. In the present invention, the silicon alkoxide-based coating agent used in the inventions of claims 1 and 3 (hereinafter referred to as (A))
And two types of inorganic coating agents of the silicon alkoxide type coating agent (hereinafter referred to as (B)) used in the inventions of claims 2 and 4 are used. First, regarding the silicon alkoxide type coating agent (A) explain.

The silicon alkoxide-based coating agent (A) has a general formula (R ¹ ) _m Si (OR ² ) _4-m (I) (wherein each R ¹ represents a methyl group, an ethyl group or a phenyl group). , R ² each represent an alkyl group having 1 to 8 carbon atoms.
m is 0, 1 or 2. ) Containing at least one of a silicon compound represented by the formula (4) and a partial hydrolyzate thereof as a main component, and a mixture containing the following compounds (i), (ii) and (iii) as main components is suitable. It can be obtained by diluting with a solvent, adding a necessary amount of a curing agent and a catalyst, and conducting hydrolysis and polycondensation, and having a weight average molecular weight MW of 5 in terms of polystyrene.
It is desirable that the molecular weight distribution is from 00 to 3000 and the molecular weight distribution MW / MN (MN is a number average molecular weight) is from 1.1 to 3.0. More preferably MW = 600-3000 and MW
/MN=1.2 to 1.8. When the weight average molecular weight and the molecular weight distribution are smaller than this range, the curing shrinkage during polycondensation becomes large, and the coating film tends to crack easily after baking. When the weight average molecular weight and the molecular weight distribution are larger than this range, the reaction is too slow to be cured, or a soft coating film is obtained even when cured,
The leveling property of the coating film tends to be very poor. (I): 20 to 200 parts by weight of a silicon compound represented by m = 0 and colloidal silica in the general formula (I) (ii): 100 parts by weight of a silicon compound represented by m = 1 in the general formula (I) (iii ): 0 to 80 parts by weight of a silicon compound represented by m = 2 in the general formula (I) As these silicon compounds, alkoxysilanes in the following formula (II) can be used. The colloidal silica as the component (i) is used by dispersing a fine particle silica component in an organic solvent such as water or methanol or a mixed solvent thereof, but as long as they are colloidal, their particle size, solvent species, etc. Is not particularly limited. The content of the colloidal silica as the component (i) is the weight part including the dispersion medium.

The above-mentioned curing agent which is optionally used in the silicon alkoxide coating agent (A) is not particularly limited, but examples thereof include inorganic acids such as hydrochloric acid, phosphoric acid and sulfuric acid, and formic acid, An acidic catalyst such as a dilute solution of an organic acid such as acetic acid or chloroacetic acid, or a basic catalyst described below can be used alone or in combination of two or more kinds. When colloidal silica is used as the component (i), the colloidal silica exhibits acidity, and this serves as a catalyst, so that nothing needs to be added as an acidic catalyst.

A basic catalyst is used as the above-mentioned catalyst which is optionally used in the silicon alkoxide coating agent (A). The basic catalyst is not particularly limited, but examples thereof include amines such as triethanolamine; γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, and the like. Aminosilanes; inorganic acids (eg hydrochloric acid, nitric acid, phosphoric acid, etc.) or organic acids (eg formic acid,
Ammonia, acetic acid, propionic acid, etc.) such as ammonia, trimethylamine, triethylamine, n-butylamine, or the like, or a metathesis salt of a salt of an inorganic acid or an organic acid and a quaternary ammonium salt can be exemplified. There is no limitation on the kind and the addition amount of these.

In the silicon alkoxide coating agent (A), in addition to the above-mentioned components, if necessary, a filler other than colloidal silica (for example, an inorganic filler such as alumina sol or fumed silica), a coloring agent, and a diluent. One or more kinds of various additives such as a solvent, a thickener, a surfactant and an ultraviolet absorber can be blended. Examples of the diluent solvent include methanol, ethanol, isopropanol (IP
Examples thereof include alcohols such as A); cellosolves such as ethylene glycol, methyl cellosolve, ethyl cellosolve, and butyl cellosolve, and these can be used alone or in combination of two or more.

The silicon alkoxide coating agent (A) can be stably used within the above-mentioned molecular weight range by adjusting its pH value to 3.8 to 6.0. If the pH value is outside this range, the stability of the silicon alkoxide-based coating agent (A) becomes poor and the usable period after the coating agent is prepared may be limited. Here, the pH value adjusting method is not particularly limited, but for example, when the pH value becomes less than 3.8 when the raw materials of the silicon alkoxide coating agent (A) are mixed, the above-mentioned predetermined value is determined by using a basic reagent such as ammonia. The pH value may be adjusted within the range, and when the pH value exceeds 6.0, it may be adjusted within the above-mentioned predetermined range using an acidic reagent such as hydrochloric acid. Also, depending on the pH value, the reaction does not proceed conversely while the molecular weight is small, and when it takes time to reach the above molecular weight range, the silicon alkoxide coating agent (A) is heated to accelerate the reaction. Alternatively, the pH value may be lowered with an acidic reagent to advance the reaction, and then the pH value may be returned to a predetermined pH value with a basic reagent.

Even if the pH value is adjusted or not adjusted as described above, if a basic catalyst is added to the silicon alkoxide coating agent (A) before the use or at least during the use, a condensation reaction can occur. Promote
Since the number of crosslinking points in the coating film can be increased, a coating film having good crack resistance can be stably obtained.
Further, by promoting the crosslinking reaction, the curing time can be shortened or the curing temperature can be lowered,
It is economical.

Next, the silicon alkoxide type coating agent (B) will be described. The silicon alkoxide-based coating agent (B) includes (a) a general formula (R ³ ) _n SiX _4-n (II) (wherein, R ³ is a substituted or unsubstituted C 1 to C 8 group, respectively).
Represents a monovalent hydrocarbon group, and X represents a hydrolyzable group.
n is an integer of 0-3. ) In the colloidal silica dispersed in at least one of an organic solvent and water, the hydrolyzable organosilane represented by
A silica-dispersed oligomer solution of organosilane obtained by partial hydrolysis under the condition of using 0.1 to 0.5 mol; and (b) an average composition formula R ⁴ _d Si (OH) _e O _{(4-de) / 2.} (III) (In the formula, R ⁴ represents the same or different substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and d and e
Are 0.2 ≦ d ≦ 2.0 and 0.0001 ≦ e ≦, respectively.
3, a number satisfying the relationship of d + e <4. ), A polyorganosiloxane containing a silanol group in the molecule, and (c) a catalyst containing three components (a), (b), and (c) as essential components. Component) contains 5 to 95% by weight of silica as a solid content, and at least 50 mol% of the hydrolyzable organosilane is an organosilane of n = 1, relative to 1 to 99 parts by weight of the component (a) ( It is preferable to add b) 99 to 1 part by weight (the total amount of both is 100 parts by weight).

The silica-dispersed oligomer as the component (a) used in the silicon alkoxide-based coating agent (B) is the main component of the base polymer having the hydrolyzable group X as a functional group that is involved in the curing reaction during film formation. . This is because the colloidal silica dispersed in an organic solvent, water, or a mixed solvent thereof has the above general formula (I
It is obtained by adding one or more kinds of hydrolyzable organosilane represented by the formula (I) and partially hydrolyzing the hydrolyzable organosilane with water in colloidal silica or water added separately.

R ³ in the hydrolyzable organosilane represented by the general formula (II) is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, such as a methyl group or an ethyl group, Propyl group, butyl group, pentyl group, hexyl group,
Alkyl group such as heptyl group and octyl group; Cycloalkyl group such as cyclopentyl group and cyclohexyl group; 2
-Aralkyl groups such as phenylethyl group and 3-phenylpropyl group; aryl groups such as phenyl group and tolyl group;
Alkenyl groups such as vinyl group and allyl group; halogen-substituted hydrocarbon groups such as chloromethyl group, γ-chloropropyl group, 3,3,3-trifluoropropyl group; γ-methacryloxypropyl group, γ-glycidoxy Propyl group,
Examples thereof include substituted hydrocarbon groups such as 3,4-epoxycyclohexylethyl group and γ-mercaptopropyl group. Among these, an alkyl group having 1 to 4 carbon atoms and a phenyl group are preferred because of their ease of synthesis or availability.

Examples of the hydrolyzable group X in the general formula (II) include an alkoxy group, an acetoxy group, an oxime group, an enoxy group, an amino group, an aminoxy group and an amide group. Among these, an alkoxy group is preferable because it is easily available and the silica-dispersed oligomer solution (a) is easily prepared. As such a hydrolyzable organosilane, n in the general formula (II) is an integer of 0 to 3,
Mono-, di-, tri-, tetra-functional alkoxysilanes, acetoxysilanes, oxime silanes,
Examples thereof include enoxysilanes, aminosilanes, aminoxysilanes, amidosilanes and the like. Among these, alkoxysilanes are preferable because they are easily available and the silica dispersion oligomer solution (a) is easily prepared. As the alkoxysilanes, the same silicon compounds as those used in the above-mentioned silicon alkoxide coating agent (B) can be used.

Particularly, tetramethoxysilane, tetraethoxysilane and the like can be exemplified as the tetraalkoxysilane of n = 0, and methyltrimethoxysilane and methyltriethoxysilane can be exemplified as the organotrialkoxysilane of n = 1. , Methyltriisopropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, and the like. N = 2
Examples of the diorganodialkoxysilane include dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, and methylphenyldimethoxysilane. Further, as the triorganoalkoxysilane of n = 3, trimethylmethoxysilane, trimethylethoxysilane, trimethylisopropoxysilane, dimethylisobutylmethoxysilane and the like can be exemplified. An organosilane compound generally called a silane coupling agent can also be used as the alkoxysilanes.

Of these hydrolyzable organosilanes of the general formula (II), 50 mol% or more is represented by n = 1.
It is preferably functional. More preferably 6
It is 0 mol% or more, and most preferably 70 mol% or more. If the trifunctional n = 1 is less than 50 mol%,
It is difficult to obtain a sufficient coating film hardness, and the dry curability tends to deteriorate.

As the colloidal silica used in the component (a), water-dispersible or non-aqueous organic solvent-dispersed colloidal silica such as alcohol can be used.
The same colloidal silica as the above-mentioned silicon alkoxide coating agent (A) can be used. Generally, such colloidal silica contains 20 to 50% by weight of silica as a solid content, and the amount of silica can be determined from this value.

When water-dispersible colloidal silica is used, water present as a component other than the solid content can be used for hydrolysis of the component (a). Water-dispersible colloidal silica is usually made from water glass, but such colloidal silica can be easily obtained as a commercial product. The organic solvent-dispersible colloidal silica can be easily prepared by replacing the water of the water-dispersible colloidal silica with an organic solvent. Such an organic solvent-dispersible colloidal silica can be easily obtained as a commercial product like the water-dispersible colloidal silica. The type of organic solvent in which colloidal silica is dispersed is, for example, lower aliphatic alcohols such as methanol, ethanol, isopropanol, n-butanol, and isobutanol; ethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, and the like. Glycol derivatives: diethylene glycol, diethylene glycol derivatives such as diethylene glycol monobutyl ether, diacetone alcohol and the like can be mentioned. One kind or two or more kinds selected from the group consisting of these can be used. Toluene, xylene, ethyl acetate, etc. can be used in combination with these hydrophilic organic solvents.
Butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methyl ethyl ketoxime and the like can also be used.

The colloidal silica in the component (a) is essential for increasing the hardness of the cured coating of the silicon alkoxide coating agent (B). Colloidal silica in the component (a) has a silica solid content of 5 to 9
It is preferably contained in the range of 5% by weight. The range is more preferably 10 to 90% by weight, and most preferably 20 to 85% by weight. If the content is less than 5% by weight, the desired coating hardness cannot be obtained, and if it exceeds 95% by weight, it is difficult to uniformly disperse silica, and there is a possibility that the component (a) may cause inconvenience such as gelation. .

The silica-dispersed oligomer of organosilane of component (a) is usually obtained by partially hydrolyzing the hydrolyzable organosilane of the general formula (II) in at least one of water-dispersible colloidal silica and organic solvent-dispersed colloidal silica. It can be obtained by disassembling. The amount of water used with respect to the hydrolyzable organosilane is preferably 0.001 to 0.5 mol of water with respect to 1 mol of the hydrolyzable group X. If the amount of water used is less than 0.001 mol, a sufficient partial hydrolyzate cannot be obtained, and if the amount of water used exceeds 0.5 mol, the stability of the partial hydrolyzate may deteriorate. There is. The method of partial hydrolysis is not particularly limited, it is sufficient to mix the hydrolyzable organosilane and colloidal silica and add the required amount of water, at which time the partial hydrolysis reaction proceeds at room temperature, You may make it heat at 60-100 degreeC in order to accelerate | stimulate a partial hydrolysis reaction. Further, for the purpose of accelerating the partial hydrolysis reaction, hydrochloric acid, acetic acid, silane halide, chloroacetic acid, citric acid,
An inorganic or organic acid such as benzoic acid, dimethylmalonic acid, formic acid, propionic acid, glutaric acid, glycolic acid, maleic acid, malonic acid, toluenesulfonic acid or oxalic acid may be used as a catalyst. The silica-dispersed oligomer of organosilane of component (a) has a pH value in the range of 2.0 to 7.0, more preferably pH 2.5 to 6.5, in order to obtain stable performance over a long period of time. Is more preferably adjusted to a pH range of 3.0 to 6.0. pH
When the value is out of this range, the long-term performance deterioration of the component (a) may be remarkable especially when the amount of water used is 0.3 mol or more per X1 mol. If the pH value of the component (a) is outside this range, a basic reagent such as ammonia or ethylenediamine is added when the pH value is outside this range,
The H value may be adjusted, and when the H value is more basic than this range, the pH value may be adjusted using an acidic reagent such as hydrochloric acid, nitric acid or acetic acid. The method of this adjustment is not particularly limited.

The silanol group-containing polyorganosiloxane of the component (b) used in the silicon alkoxide coating agent (B) has an average compositional formula represented by the above formula (III), and R in the formula (III) is ⁴ above (II)
The same as R ³ in the formula can be exemplified, but R ⁴
It preferably contains 5 to 50% by weight of a phenyl group. If it is less than 5% by weight, the elongation of the coating film is lowered and cracks are likely to occur, and if it exceeds 50% by weight, curing may be too slow. Other R ⁴ is preferably an alkyl group having 1 to 4 carbon atoms, vinyl group, γ-glycidoxypropyl group, γ-methacryloxypropyl group, γ-aminopropyl group, 3,3,3-trifluoropropyl. A substituted hydrocarbon group such as a group, more preferably an alkyl group such as a methyl group and an ethyl group. In the formula (III), d and e
Are 0.2 ≦ d ≦ 2.0 and 0.0001 ≦ e ≦, respectively.
3 and d + e <4. If d is less than 0.2 or e is more than 3, there is an inconvenience such as cracking in the cured film, and d is more than 2.0 and 4 or less. In the case or when e is less than 0.0001, curing does not proceed well.

Such silanol group-containing polyorganosiloxane of the formula (III) is, for example, one or two of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or an alkoxysilane corresponding thereto. It can be obtained by hydrolyzing the above mixture with a large amount of water by a known method. When a silanol group-containing polyorganosiloxane is hydrolyzed by a known method using an alkoxysilane, a small amount of unhydrolyzed alkoxy groups may remain. That is, a polyorganosiloxane in which a silanol group and a trace amount of an alkoxy group coexist may be obtained, but such a polyorganosiloxane may be used.

The molecular weight of the silanol group-containing polyorganosiloxane of component (b) is 700 to 200.
00 is preferable. The molecular weight referred to here is a weight average molecular weight in terms of standard polystyrene measured by GPC (gel permeation chromatography), and when it is less than 700, the curability of the formed coating film is slow and cracks are likely to occur. When it exceeds 20000, a pigment-added silicon alkoxide coating agent (B)
The coating film formed from is not glossy and may have poor smoothness.

The curing catalyst of the component (c) used in the silicon alkoxide coating agent (B) is the above-mentioned (a).
It accelerates the condensation reaction between the component and the component (b) to cure the coating. Such catalysts include metal salts of carboxylic acids such as alkyl titanates, tin octylate and dibutyltin dilaurate, dioctyltin dimaleate;
Amine salts such as dibutylamine-2-hexoate, dimethylamine acetate, ethanolamine acetate;
Carboxylic acid quaternary ammonium salts such as tetramethylammonium acetate; amines such as tetraethylpentamine; N
Amine-based silane coupling agents such as -β-aminoethyl-γ-aminopropyltrimethoxysilane and N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane; acids such as p-toluenesulfonic acid, phthalic acid and hydrochloric acid Aluminum compounds such as aluminum alkoxides and aluminum chelates, alkali catalysts such as potassium hydroxide, titanium compounds such as tetraisopropyl titanate, tetrabutyl titanate, titanium tetraacetylacetonate, methyltrichlorosilane, dimethyldichlorosilane, trimethylmonochlorosilane, etc. There are halogenated silanes and the like, but other than these, there is no particular limitation as long as they are effective for the condensation reaction between the component (a) and the component (b).

The mixing ratio of the components (a) and (b) is
(B) Component 99-1 to (a) Component 1-99 parts by weight
Parts by weight, preferably 95 to 5 parts by weight of component (b) with respect to 5 to 95 parts by weight of component (a), and more preferably 90 to 10 parts by weight of component (b) with respect to 10 to 90 parts by weight of component (a).
10 parts by weight (however, the total amount of the components (a) and (b) is 100 parts by weight). When the amount of the component (a) is less than 1 part by weight, the room temperature curability is poor and sufficient coating hardness cannot be obtained. On the other hand, when the amount of the component (a) exceeds 99 parts by weight, the curability may be unstable and a good coating may not be obtained.

The addition amount of the curing catalyst of the component (c) is
It is preferably 0.0001 to 10 parts by weight based on 100 parts by weight of the total of the components (a) and (b). It is more preferably 0.0005 to 8 parts by weight, and most preferably 0.0007 to 5 parts by weight. If the addition amount of the curing catalyst (c) is less than 0.0001 parts by weight, it may not be cured at room temperature, and if the addition amount of the curing catalyst (c) exceeds 10 parts by weight, the heat resistance and weather resistance of the coating film may be deteriorated. It may get worse.

When the silicon alkoxide-based coating agent (A) or (B) prepared as described above is used as an intermediate coating, a coloring pigment is dispersed for hiding and protecting the base or imparting designability. It becomes necessary to do.
As the pigment type to be added, carbon black, quinacdrine, naphthol red, cyanine blue, cyanine green, organic pigments such as Hansa yellow, titanium oxide,
Inorganic pigments such as barium sulfate, rouge, calcium carbonate, alumina, iron oxide red, and complex metal oxides are preferable, and one or more selected from these groups can be used in combination. Among them, inorganic pigments are preferable for improving weather resistance. The particle size of the pigment is not particularly limited, but is preferably about 0.01 to 2 μm.

The amount of the pigment added is not particularly limited because the hiding property varies depending on the type of the pigment, but in the case of an inorganic coating, it is preferably in the range of 15 to 80 parts by weight with respect to 100 parts by weight of the resin solid content. If the amount is less than 15 parts by weight, the hiding property cannot be sufficiently obtained, and if the amount exceeds 80 parts by weight, the smoothness of the coating film may be deteriorated. The pigment can be dispersed by an ordinary method, and at that time, a dispersant, a dispersion aid, a thickener, a coupling agent and the like can be used.

When the silicon alkoxide type coating agent (A) or (B) is used as an inorganic coating material, it can be coated by a usual coating method. For example, various coating methods such as brush coating, spraying, dipping, flow, roll, curtain and knife coating can be adopted. Further, it can be diluted with an organic solvent before use, and the dilution ratio is not particularly limited and may be determined as necessary. The thickness of the coating film is not particularly limited and may be about 0.1 to 100 μm, but in order to prevent the coating film from adhering stably and cracking or peeling in the long term, The range of 80 μm is preferable.

Next, the coating of a metallic material on the base will be described. FIG. 1 shows an example in which an undercoat 2 of a primer, an intermediate coat 3 of an enamel paint containing a pearl pigment, and an overcoat 4 of a clear paint are applied in this order on a surface of a base 1 of a metal material. FIG. 2 shows an example in which the surface of a metal base 1 is coated with a primer undercoat 2, an enamel paint intermediate coat 3, and a clear paint topcoat 4 containing a pearl pigment in this order. In FIG. 2, a clear topcoat 5 of clear paint may be further applied on the topcoat 4 if necessary.

The undercoat 2 can be formed by applying a primer to the surface of the degreased base 1 such as steel plate, aluminum or stainless steel, and drying and curing at a temperature of 200 ° C. or lower. The primer is not particularly limited as long as the adhesion between the metal of the base 1 and the intermediate coating 3 is good, and an epoxy-based, acryl-silicone-based or isocyanate-based primer can be exemplified. In order to improve the adhesion with the undercoat 2, the surface of the metal plate to be the base 1 may be subjected to a surface treatment such as chemical polishing or chromate treatment, and various surface treatment agents may be used. Primer primer 2
The film thickness of is not particularly limited, and is 0.1 to 100.
It may be about 0 μm.

In the present invention, as the enamel coating for the intermediate coating 3, a coating in which a pigment is dispersed in the silicon alkoxide coating agent (A) or (B) is used. In the example of FIG. 1, a pearl pigment is blended with the silicon alkoxide-based coating agent (A) or (B) in which the pigment is dispersed in order to perform metallic coating. As the pearl pigment, mica or metal powder coated with titanium on the surface can be used, and the pearl pigment content is set so that 5 to 90% by weight of the pigment component is replaced with the pearl pigment. Good.
That is, it is preferable to add the pearl pigment in an amount of 5 to 90% by weight based on the total amount of the pigment and the pearl pigment.
If it is less than 5% by weight, the metallic appearance may not be sufficiently obtained, and if it exceeds 90% by weight, the hiding property may not be sufficiently obtained. The particle size of the pearl pigment may be in the range of 0.1 to 100 μm. 0.
If it is less than 1 μm, the metallic appearance may not be obtained, and if it exceeds 100 μm, a smooth coating film may not be obtained. The film thickness of the intermediate coating 3 may be in the range of about 3 to 100 μm, preferably 5 to 50 μm, and more preferably 10 to 30 μm.

In the example of FIG. 1, after the metallic intermediate coating 3 is applied in this way, a clear coating is applied on the metallic intermediate coating 3 for the purpose of surface protection, and a top coating 4 is applied. The clear coating material is not particularly limited, but weather resistance and corrosion resistance can be further enhanced by using the silicon alkoxide-based coating agent (A) or (B) containing no pigment as the clear coating material. Topcoat 4 has a thickness of 1 to 50
It may be in the range of about μm, preferably 2 to 30 μm
m, and more preferably 3 to 20 μm.

In the example of FIG. 2, a pigment is dispersed in the silicon alkoxide-based coating agent (A) or (B) as the enamel coating for the intermediate coating 3 (either with or without the pearl pigment). However, the intermediate coating 3 is applied in the same manner as above. The thickness of the intermediate coating 3 is 3 to
It may be in the range of about 100 μm, preferably 5 to 5
It is 0 μm, more preferably 10 to 30 μm. After the intermediate coating 3 is applied and baked as described above, a clear coating containing a pearl pigment is used to apply a top coating 4 for metallic coating. As the pearl pigment, mica or metal powder coated with titanium can be similarly used, and a pearl pigment in an amount of 1 to 50% by weight based on the solid content of the clear coating is used. If it is less than 1% by weight, a metallic appearance may not be obtained, and if it exceeds 50% by weight, a continuous film may not be formed. The particle size of the pearl pigment may be in the range of 0.1 to 100 μm. 0.
If it is less than 1 μm, the metallic appearance may not be obtained, and if it exceeds 100 μm, a smooth coating film may not be obtained.

The clear coating of the top coating 4 is not particularly limited, but weather resistance and corrosion resistance can be further enhanced by using the silicon alkoxide type coating agent (A) or (B) containing no pigment. it can. The film thickness of the top coat 4 of the clear paint containing the pearl pigment varies depending on the mixing ratio of the pearl pigment.
It may be in the range of about 50 μm, preferably 2 to 30.
μm, and more preferably 3 to 20 μm.

In the example of FIG. 2, a clear topcoat 5 may be applied by further coating a clear paint on the topcoat 4 of the clear paint containing the pearl pigment. The clear coating of the clear topcoat 5 is not particularly limited, but weather resistance and corrosion resistance can be further enhanced by using the silicon alkoxide coating agent (A) or (B) containing no pigment. The thickness of the clear topcoat 5 may be in the range of about 1 to 50 μm, preferably 2 to 30 μm, and more preferably 3 to 20 μm.

[0042]

[Preparation of Silicon Alkoxide Coating Agent (A)]

(A-1) 100 parts of methyltrimethoxysilane, 20 parts of tetraethoxysilane, isopropyl alcohol organosilica sol (“OSCA manufactured by Catalysis Chemicals Co., Ltd.”)
L1432 ", SiO ₂ content 30%) 150 parts, dimethyldimethoxysilane 40 parts and isopropyl alcohol 100 parts were mixed, and 200 parts of water was further added and stirred, and the molecular weight Mw was kept in a constant temperature bath at 60 ° C. By adjusting to 1200, a silicon alkoxide coating agent (A) was prepared. This is a coating agent (A-
1).

(A-2) Coating agent (A-1) 10
45 parts of titanium oxide TR-92 (manufactured by Thai Oxide Co., average particle size of about 0.3 μm) was added to 0 parts of the mixture, and the mixture was dispersed by stirring with a homodisper for 10 minutes. This is designated as a coating agent (A-2). (A-3) 25 parts of titanium oxide TR-92 and 100 parts of coating agent (A-1), and pearl mica iridin 121wi which is titanium coated on mica.
(Merck Japan KK, titanium oxide coverage 15-65
%) Was added, and the mixture was stirred with a homodisper for 10 minutes to disperse. This is designated as a coating agent (A-3).

(A-4) Coating agent (A-1) 10
Pearl mica iridin 121wi for 0 copy
3 parts of I was added, and the mixture was stirred with a homodisper for 10 minutes to disperse. This is designated as a coating agent (A-4).

(A-5) Coating agent (A-1) 10
40 parts of titanium oxide TR-92 and 2 parts of pearl mica IRIODIN 121WII were added to 0 part of the mixture, and the mixture was stirred with a homodisper for 10 minutes to disperse. This is designated as a coating agent (A-5). (A-6) 5 parts of titanium oxide TR-92, 100 parts of coating agent (A-1), pearl mica IRIOD
Add 55 parts of IN 121WII and add 1 with a homodisper.
Stir for 0 minutes to disperse. This is a coating agent (A
-6).

The above coating agents (A-1) to (A-
Regarding 6), Table 1 shows the compounding parts of titanium oxide (pigment) and pearl mica (metalliking agent).

[0047]

[Table 1]

[Preparation of Silicon Alkoxide-Based Coating Agent (B)] “Preparation of (a) Component” (a-1) Methanol-dispersed colloidal silica sol MT- in a flask equipped with a stirrer, heating jacket, condenser and thermometer. ST (Nissan Chemical Co., Ltd., particle size 10 to 20 μm, solid content 30%, H ₂ O 0.5%) 1
00 parts, methyltrimethoxysilane 68 parts, water 10.8
Parts were added, the partial hydrolysis reaction was carried out at a temperature of 65 ° C. for about 5 hours with stirring, and the component (a) was obtained by cooling. This product had a solid content of 36% when left to stand at room temperature for 48 hours. Let this (a) component be (a-1). Preparation conditions for (a-1):-Number of moles of water relative to 1 mol of hydrolyzable group X 0.4-Silica content of component (a) 47.3% -Containing hydrolyzable group n = 1 Mol% of organosilane ... 100 mol% (a-2) Isopropyl alcohol-dispersed colloidal silica sol IPA-ST (manufactured by NISSAN CHEMICAL INDUSTRIES CO., LTD., Particle size 10-20 μm) in a flask equipped with a stirrer, heating jacket, condenser and thermometer. , Solid content 30%, H ₂ O
0.5%) 100 parts, methyltrimethoxysilane 68
Parts, dimethyldimethoxysilane 18 parts, water 2.7 parts, acetic anhydride 0.1 part were added, a partial hydrolysis reaction was carried out at a temperature of 80 ° C. for about 3 hours with stirring, and the mixture was cooled ( The component a) was obtained. This product had a solid content of 36% when left to stand at room temperature for 48 hours. Let this (a) component be (a-2). Preparation conditions for (a-2):-Number of moles of water relative to 1 mol of hydrolyzable group X-0.1-Silica content of component (a)-40.2% -Containing hydrolyzable group of n = 1 Mol% of organosilane ... 77 mol% (a-3) 4 parts of titanium oxide TR-92 to 100 parts of (a-2).
5 parts were added, and the mixture was stirred for 10 minutes with a homodisper to disperse. This is designated as (a-3).

(A-4) 2 parts of titanium oxide TR-92 was added to 100 parts of (a-2).
5 copies, 2 pearl mica IRIODIN 121WII
0 part was added, and the mixture was stirred for 10 minutes with a homodisper to disperse. This is designated as (a-4). (A-5) (a-2) Pearl mica IRIODI for 100 parts
N 121WII (3 parts) was added, and the mixture was dispersed by stirring with a homodisper for 10 minutes. This is designated as (a-5).

(A-6) (a-2) Pearl mica IRIODI for 100 parts
Add 0.1 part of N 121WII and add 1 with a homodisper.
Stir for 0 minutes to disperse. This is designated as (a-6). (A-7) (a-2) Pearl mica IRIODI for 100 parts
Add 55 parts of N 121 WII and use homodisper 10
Stir for minutes to disperse. This is a coating agent (a-
7).

(A-1) to (a-7) of the above component (a)
Table 2 shows the compounding parts of titanium oxide (pigment) and pearl mica (metalliking agent).

[0052]

[Table 2]

[Preparation of component (b)] (b-1) 1000 ml of water was added to a flask equipped with a stirrer, a heating jacket, a condenser, a dropping funnel and a thermometer.
0 parts and 50 parts of acetone were weighed out, and 59.7 parts (0.4 mol) of methyltrichlorosilane, 51.6 parts (0.4 mol) of dimethyldichlorosilane, and 42.3 parts of phenyltrichlorosilane were mixed in the mixed solution. What melt | dissolved (0.2 mol) in 200 parts of toluene was hydrolyzed while dripping under stirring. After 40 minutes from the dropping, the stirring was stopped, the reaction solution was transferred to a separating funnel and allowed to stand still, the lower layer hydrochloric acid water separated into two layers was separated and removed, and then the toluene solution of the upper organopolysiloxane was depressurized. Water and hydrochloric acid remaining by stripping were removed by distillation together with excess toluene to obtain a 60% toluene solution of a silanol group-containing organopolysiloxane having an average molecular weight of 3000. This (b)
Let the component be (b-1). This product has an amount of phenyl groups in R ⁴ of 14%.

(B-2) 10000 parts of water and 50 parts of acetone were weighed into a flask equipped with a stirrer, a heating jacket, a condenser, a dropping funnel and a thermometer, and 44.8 parts of methyltrichlorosilane were added to the mixed solution. 0.3
Mol), 38.7 parts (0.3 mol) of dimethyldichlorosilane, and 84.6 parts (0.4 mol) of phenyltrichlorosilane dissolved in 200 parts of toluene were hydrolyzed while being added dropwise with stirring. After 40 minutes from the dropping, the stirring was stopped, the reaction solution was transferred to a separating funnel and allowed to stand still, the lower layer hydrochloric acid water separated into two layers was separated and removed, and then the toluene solution of the upper organopolysiloxane was depressurized. Water and hydrochloric acid remaining by stripping were removed by distillation together with excess toluene to obtain a 60% toluene solution of a silanol group-containing organopolysiloxane having an average molecular weight of 3000. Let this (b) component be (b-2). This is R
^The amount of phenyl groups in ⁴ is 30.8%.

"Preparation of component (a), component (b), component (c)" Component (a), component (b), N-β-aminoethyl-γ-aminopropyl as component (c) of the curing catalyst. Methyldimethoxysilane was weighed in the blending amounts shown in Table 3, and these were mixed and stirred to prepare a silicon alkoxide coating agent (B). Each of Table 3 is set as coating agents (B-1) to (B-7).

[0056]

[Table 3]

(Example 1) 1 mm thick stainless steel plate (S
US304) cut into a size of 7 × 15 cm is used as a base 1, and after degreasing and drying the surface, “E-1 primer F-0391” manufactured by Isamu Paint Co., Ltd. is spray-coated and baked at 150 ° C. for 20 minutes. By
An undercoat 2 having a film thickness of 20 μm was applied. Next, a coating agent (A-3) was prepared as an enamel paint containing a pearl pigment.
Was sprayed on this for 10 minutes and then baked at 150 ° C. for 20 minutes to give an intermediate coating 3 having a film thickness of 15 to 20 μm. Furthermore, a coating agent (A-
Spray 1) onto this and set to 10
After performing the coating for 5 minutes, the top coating 3 having a film thickness of 5 to 10 μm was applied by baking at 150 ° C. for 20 minutes. Thus, a building material having a coating film constitution as shown in FIG. 1 was obtained.

Example 2 An intermediate coating 3 was applied using a coating agent (B-4) as an enamel coating containing a pearl pigment, and a coating agent (B-
Example 1 except that the top coat 4 was applied using 1).
In the same manner as described above, a building material having a coating film constitution as shown in FIG. 1 was obtained.

Comparative Example 1 An intermediate coating 3 was applied using a coating agent (A-5) as an enamel paint containing a pearl pigment, and a coating agent (A-) was applied as a clear paint.
Example 1 except that the top coat 4 was applied using 1).
In the same manner as described above, a building material having a coating film constitution as shown in FIG. 1 was obtained.

Comparative Example 2 An intermediate coating 3 was applied using a coating agent (A-6) as an enamel paint containing a pearl pigment, and a coating agent (B-as a clear paint).
Example 1 except that the top coat 4 was applied using 1).
In the same manner as described above, a building material having a coating film constitution as shown in FIG. 1 was obtained.

(Example 3) Undercoat 2 is applied to base 1 in the same manner as in Example 1, and coating agent (A-2) as an enamel paint is sprayed thereon as in Example 1 and baked. To give an intermediate coating 3. Further, a coating agent (A-4) was applied as a clear coating in which a pearl pigment was blended thereon by spraying in the same manner as in Example 1 and baked to give Topcoat 4. Further, a coating agent (A-1) as a clear coating was applied thereon by spraying, setting was performed for 10 minutes, and then baking was performed at 150 ° C. for 20 minutes to apply a clear top coating 5 having a film thickness of 5 to 10 μm. In this way, a building material having a coating composition as shown in FIG. 2 was obtained.

(Example 4) Intermediate coating 3 was applied using the coating agent (B-3) as an enamel coating, and the coating agent (B-
5) was used to apply the topcoat 4, and the coating agent (B-2) was used as the clear paint to apply the clear topcoat 5 in the same manner as in Example 3 except that the coating composition shown in FIG. Got building materials.

Example 5 An intermediate coating 3 was applied using the coating agent (A-2) as an enamel coating, and a coating agent (B-
5) was used to apply the top coat 4 (there was no clear top coat 5), and in the same manner as in Example 3, a building material having a coating composition as shown in FIG. 2 was obtained.

(Comparative Example 3) Intermediate coating 3 was applied using the coating agent (A-2) as the enamel coating, and the coating agent (B- was used as the clear coating containing the pearl pigment).
6) was used to apply the top coat 4, and the coating agent (A-1) was used as the clear paint to apply the clear top coat 5 in the same manner as in Example 3 except that the coating composition shown in FIG. Got building materials.

Comparative Example 4 Intermediate coating 3 was applied using coating agent (B-4) as an enamel coating material, and coating agent (B-
7) was used to apply the top coat 4, and the coating agent (B-2) was used as the clear paint to apply the clear top coat 5 in the same manner as in Example 3 except that the coating composition shown in FIG. Got building materials.

(Comparative Example 5) A commercial acrylic organic coating was sprayed to apply the intermediate coating 3, and the pearl mica IRIOD was added to the acrylic organic coating at a solid content of 3%.
IN 121WII was added and sprayed to apply topcoat 4 (no clear topcoat 5),
In the same manner as in Example 3, a building material having a coating film configuration as shown in FIG. 2 was obtained. The acrylic organic coating was set for 10 minutes after coating and baked at 200 ° C. for 20 minutes.

Table 5 collectively shows the coating configurations of Examples 1 to 5 and Comparative Examples 1 to 5.

[0068]

[Table 4]

The building materials obtained in Examples 1 to 5 and Comparative Examples 1 to 5 as described above were observed for appearance and tested for weather resistance, coating adhesion and corrosion resistance. The test method is as follows. -Observation of appearance ... Visual observation of the coated article was performed to evaluate whether or not a metallic appearance was obtained.・ Weather resistance: Eye super UV tester with UV irradiation (100 mW / cm ² ) -temperature 63 ° C.-humidity 50% for 8 hours, no UV irradiation-temperature 35 ° C.-humidity 90% or more (condensation) Under the conditions, a test was conducted for a total of 12 hours of 4 hours, and this test was conducted under the UV irradiation time 1
The situation after evaluation up to 000 hours was evaluated.・ Cohesion of coating film: Stainless steel coated articles are soaked in boiling water for 5 hours, air-dried, and adhesive tape (cellophane tape) within 3 hours.
The peeling test was performed and evaluated. -Corrosion resistance: The condition after the salt spray test was performed for 20000 hours was visually evaluated.

The results are shown in Table 5. In the section "Appearance observation", a metallic tone is indicated by "○", and a non-metallic tone is indicated by "x".

[0071]

[Table 5]

As can be seen from Table 5, each of the examples had a good metallic appearance and had good weather resistance, coating adhesion and corrosion resistance. On the other hand, in Comparative Examples 1 and 3 in which the pearl pigment content is small, it is not possible to obtain a good metallic appearance, and in Comparative Examples 2 and 4 in which the pearl pigment content is too high, the coating adhesion is poor. There was a problem. Further, in Comparative Example 5 using the organic paint, there was a problem in weather resistance and corrosion resistance.

[0073]

INDUSTRIAL APPLICABILITY In the present invention, the silicon alkoxide coating agent (A) or (B) having the above composition is used as an intermediate coating, and the intermediate coating of the silicon alkoxide coating agent (A) or (B) is a pigment. And a pearl pigment in an amount of 5 to 90% by weight based on the total amount of the pigment and the pigment, or a pearl pigment of 1 to 50% by weight of solid content in an overcoating agent. It is possible to obtain a metal-based building material that can be painted by baking and has an excellent metallic appearance and excellent weather resistance and corrosion resistance.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of the present invention.

FIG. 2 is a sectional view showing another example of the present invention.

[Explanation of symbols]

1 ... Base 2 ... Undercoat 3 ... Intermediate coating 4 ... Topcoat

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI B32B 15/08 B32B 15/08 G C09D 5/00 C09D 5/00 183/04 183/04 E04C 2/08 E04C 2/08 B E04F 13/12 E04F 13/12 A (56) Reference JP-A-3-54278 (JP, A) JP-A-6-182295 (JP, A) JP-A-62-294468 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B05D 7/14 B05D 7/14 101 B05D 1/36 B05D 7/24 302 B32B 15/08 C09D 5/00 C09D 183/04 E04C 2/08 E04F 13 / 12

Claims (4)

(57) [Claims] 1. A building material formed by applying a base coat, a middle coat and a top coat on the basis of a metal-based material, and as a coating agent for the middle coat, a compound of the general formula (R ¹ ) _m Si (OR ² ) _{4- m} (In the formula, each R ¹ represents a methyl group, an ethyl group or a phenyl group, and each R ² represents an alkyl group having 1 to 8 carbon atoms.
m is 0, 1 or 2. ) A silicon alkoxide-based coating agent containing a silicon compound and / or a partial hydrolyzate thereof as a main component, and a pigment and a pearl pigment in an amount of 5 to 90% by weight based on the total amount of the pigment and the pearl pigment. A building material characterized by using the obtained material. 2. A building material formed by applying a base coat, a middle coat and a top coat on the basis of a metal-based material, and as a coating agent for the middle coat, (a) the general formula (R ³ ) _n SiX _4-n (In the formula, R ³ is each a substituted or unsubstituted C 1 to C 8
Represents a monovalent hydrocarbon group, and X represents a hydrolyzable group.
n is an integer of 0-3. ) A hydrolyzable organosilane represented by the formula (4) is partially hydrolyzed in colloidal silica dispersed in an organic solvent and / or water, and a silica-dispersed oligomer solution of organosilane (b) average composition formula R ⁴ _d Si (OH) _e O _{(4-de) / 2} (in the formula, R ⁴ is a substituted or unsubstituted C 1 to C 8
Represents a monovalent hydrocarbon group, and d and e are each 0.
It is a number that satisfies the relationship of 2 ≦ d ≦ 2.0, 0.0001 ≦ e ≦ 3, and d + e <4. ) A polyorganosiloxane containing a silanol group in the molecule, and (c) a curing catalyst, a silicon alkoxide coating containing three components (a), (b) and (c) as essential components. 5 to 90 based on the total amount of the pigment and the pigment in the agent
A building material characterized by using a mixture containing a pearl pigment in an amount of% by weight. 3. A building material formed by applying a base coat, a middle coat and a top coat on the basis of a metal-based material, and as a coating agent for the middle coat, a compound of the general formula (R ¹ ) _m Si (OR ² ) _4-m (In the formula, each R ¹ represents a methyl group, an ethyl group or a phenyl group, and each R ² represents an alkyl group having 1 to 8 carbon atoms.
m is 0, 1 or 2. ) A silicon alkoxide-based coating agent containing a silicon compound represented by (4) and / or a partial hydrolyzate thereof as a main component is used, and a pearl pigment having a solid content of 1 to 50% by weight is blended as a top coating agent. A building material characterized by that. 4. A building material formed by applying a base coat, a middle coat, and a top coat on the basis of a metal-based material, and as a coating agent for the middle coat, (a) a general formula (R ³ ) _n SiX _4-n (In the formula, R ³ is each a substituted or unsubstituted C 1 to C 8
Represents a monovalent hydrocarbon group, and X represents a hydrolyzable group.
n is an integer of 0-3. ) A hydrolyzable organosilane represented by the formula (4) is partially hydrolyzed in colloidal silica dispersed in an organic solvent and / or water, and a silica-dispersed oligomer solution of organosilane (b) average composition formula R ⁴ _d Si (OH) _e O _{(4-de) / 2} (in the formula, R ⁴ is a substituted or unsubstituted C 1 to C 8
Represents a monovalent hydrocarbon group, and d and e are each 0.
It is a number that satisfies the relationship of 2 ≦ d ≦ 2.0, 0.0001 ≦ e ≦ 3, and d + e <4. ) A polyorganosiloxane containing a silanol group in the molecule, and (c) a curing catalyst, a silicon alkoxide coating containing three components (a), (b) and (c) as essential components. A building material, characterized in that a pearl pigment having a solid content of 1 to 50% by weight is blended as an overcoating agent.