JPH10158572A - Composition for coating material of silver coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the problem of yellowing of a coated film used in a of a high-temperature condition, when a silver inactivating component is added to a coating material of silver coating comprising a silicon acrylic resin as a coated film base component. SOLUTION: A silicon acrylic resin is compounded with 0.01-5wt.% of a zirconium complex of a carboxylic acid comprising a zirconium complex of 4-methyl-γ-oxo-benzene-butanoic acid as a representative example, as a silver inactivating component to give a composition for a coating material of silver coating, excellent in adhesivity to silver surface and transparency, capable of sufficiently exhibiting malleability and ductility and beautiful surface appearance which silver has, extremely highly preventing change in color (corrosion) of silver and exceeding in durability for a long period time, not yellowing even being exposed to a high temperature of >=130 deg.C and bringing about a coated film for protective coating suitable for an evaporated silver film face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is excellent in preventing silver discoloration (corrosion) in various silver products, for example, decorative articles, tableware, electronic components, lighting equipment, etc., and in particular, has excellent discoloration resistance on silver-deposited surfaces. The present invention relates to a composition for silver-coated paint that can be provided.

[0002]

2. Description of the Related Art Silver has been used as a noble metal as a decoration, currency, tableware, electronic material, and dental material for a long time by utilizing its excellent optical properties and electrochemical properties. Its applications have rapidly increased as photographic industrial materials, semiconductor materials, conductive materials, aviation and space materials, and are widely used as industrial materials.

[0003] However, silver materials used in these applications are extremely unstable chemically, and easily react with oxygen, moisture, hydrogen sulfide, sulfur dioxide and the like in the air to produce silver oxide and silver sulfide. This has the disadvantage that the silver surface is discolored (corroded) to brown or black.

As a method for preventing such discoloration (corrosion), silver is replaced with another metal such as copper, platinum, palladium, or the like.
A method of forming an alloy with iridium, zinc, tin, or the like, or applying an epoxy resin or the like to the surface is known. However, the former method has disadvantages such as poor spreadability and poor surface appearance. In the latter case, the adhesion to the silver surface is insufficient or the durability is insufficient, and it is difficult to prevent discoloration (corrosion) of the silver surface for a long time.

[0005]

Therefore, in order to sufficiently exhibit the excellent extensibility inherent in silver and the beautiful appearance of the surface, it is necessary to protect the surface of silver itself by coating, regardless of the alloy treatment. New solution is needed, and finding a new type of coating with improved adhesion and durability to the silver surface is a challenge to be solved at the moment. Was. As a result, a new invention relating to the composition of the resin component, which is the base component of the coating agent, has been made,
Japanese Patent Application No. 5-138406 (JP-A-6-57198)
No. 7), Japanese Patent Application No. 7-51113, and Japanese Patent Application No. 8-05466.
A patent application has been filed as No. 1.

[0006] While these inventions have been found to provide a tentative solution to the above problems, in applications where the silver surface is exposed to high temperatures exceeding 130 ° C, there is the problem that the coating film turns yellow.
For this reason, further measures effective in enhancing the protection performance of the silver surface have been required.

[0007]

Means for Solving the Problems The present inventor has conducted intensive studies in view of such a situation, and as a result, from the various substances known as metal deactivators, the present inventors have cooperated with the silicone acrylic resin component. Thus, a search was made for a substance that achieves even more effective protection of the silver surface. As a result, it has been found that a specific metal deactivator is effective as a silver deactivator in combination with the specific coating substrate component, and thus a paint excellent in silver discoloration (corrosion) prevention properties. They have found that a composition can be obtained and have completed the present invention.

That is, the present invention provides, as a coating substrate component,
A composition for a silver-coated paint containing a silicone acrylic resin component, characterized in that a zirconium complex of a carboxylic acid is contained as a silver-inactivating component in an amount of 0.01 to 5% by weight in the coating film resin. The present invention relates to a coating composition.

In the present invention, the silver to be coated may be not only solid silver but also thin silver, and the effect of the invention is remarkably exerted when the silver is a silver-deposited surface.

As the zirconium complex of a carboxylic acid, a zirconium complex of a lower fatty acid having a lower alkyl-substituted benzoyl group is effective, and a particularly preferable example is 4-methyl-γ-oxo-benzene-butanoic acid ( γ-oxo-4-methylphenylbutanoic acid or p-
Toluoyl propanoic acid).

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Typical and best modes of the embodiment of the present invention are specifically exemplified in the following examples, but various constituent elements selectable in practicing the present invention. Will be described in detail below.

The silicone acrylic resin used in the present invention is a resin in which a hydrolyzable silyl group is introduced into an acrylic main chain. The silicone acrylic resin forms a siloxane-acrylic copolymer with moisture in the atmosphere, and is cured by heat or heat. One that forms and cures a siloxane-acrylic copolymer by self-crosslinking with an active energy ray is exemplified.

One of these silicone acrylic resins may be used alone, or two or more thereof may be used in combination.

As the zirconium complex of a carboxylic acid which is a silver deactivator used in the present invention, those commercially available from Ciba-Geigy as CGC1-1930 as metal deactivators are particularly preferred. By way of example, this is said to be a zirconium complex of 4-methyl-γ-oxo-benzene-butanoic acid.

The zirconium complex of a carboxylic acid is one kind of a zirconium complex of a lower fatty acid having a lower alkyl-substituted benzoyl group, but this kind may be used alone or a mixture of two or more kinds may be used. May be used.

The mixing ratio of the metal inactivating component is in the range of 0.01 to 5% by weight in the coating resin. Above all, 0.1 to 2% by weight is preferable from the viewpoint of anticorrosion.

The mixing ratio of the metal inactivating component is 0.0
If it is less than 1%, sufficient corrosion resistance cannot be obtained, and if it exceeds 5% by weight, the adhesion of the coating film to the silver surface is undesirably reduced.

These metal deactivators cooperate well with the above-mentioned various specific resin components which are paint base components constituting the paint composition of the present invention, and can effectively prevent silver corrosion. It turned out here for the first time. It is presumed that the specific resin component probably does not inhibit the action of the specific metal deactivator on the metal surface, and that the specific metal deactivator is dissolved well in the specific resin component.

Other known substances such as metal deactivators and rust preventives do not have the same effect as these substances, but some can be used in combination if necessary. I do.

Such a coating composition may further comprise a known catalyst such as a hydrolysis-condensation catalyst, a solvent, a leveling agent, a coupling agent, a defoaming agent, a matting agent, an ultraviolet absorber, an antioxidant, etc., if necessary. Can also be added.

When ultraviolet rays are used as a means for curing the coating composition of the present invention, it is usually necessary to add a photopolymerization initiator to the resin composition. The amount of the photopolymerization initiator to be added is usually 0.1 to 20% by weight, preferably 0.5 to 10% by weight, based on 80 to 99.9% by weight of the resin composition.
% By weight. If the amount is more than 20% by weight, it is not preferable because ultraviolet rays are prevented from penetrating into the inside of the coating film, curing is insufficient, and adhesion of the coating film to the silver surface is reduced.

Examples of the hydrolysis-condensation catalyst used as necessary include basic compounds such as lithium hydroxide and potassium hydroxide, metal-containing compounds such as tetraisopropyl titanate and tin octylate, and p-toluenesulfonic acid. ,
There are acidic compounds such as dialkyl phosphoric acid.

Examples of the solvent used as required include aromatic hydrocarbons such as toluene and xylene, alcohols such as methanol, ethanol and isopropyl alcohol;
Esters such as ethyl acetate, ethicello, methicello, and cellosolve acetate; ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; These solvents may be used alone or in a combination of two or more.

Specific examples of the coupling agent used as required include vinyltris (β-methoxyethoxy) silane, γ-glycidoxyproxytrimethoxysilane,
Examples thereof include silane-based, titanate-based, and aluminum-based coupling agents such as tetra (2,2'-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, acetoalkoxyaluminum, and diisopropylate. One of these coupling agents may be used alone, or two or more thereof may be used in combination.

The active energy rays used herein include ultraviolet rays, electron beams, ionizing radiation such as α-rays, β-rays, and γ-rays, microwaves, high-frequency waves, etc., as long as radical active species can be generated. , Any kind of energy is acceptable. Visible light, infrared light, and laser light may be used.

Examples of the device that generates ultraviolet light include an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a chemical lamp, a black light lamp, a mercury-xenon lamp, a short arc lamp, a helium / cadmium laser, and argon. A laser or the like may be used, and may be selected in consideration of the absorption wavelength of a compound that generates a radical active species.

Specific examples of the photopolymerization initiator include two types: a type in which a bond is cleaved in a molecule by light to generate an active species; and a type in which a hydrogen abstraction reaction is caused between molecules to generate an active type. Can be different. Examples of the former include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal,
1- (4-isopropylphenyl) -2-hydroxy-
2-methylpropan-1-one,

4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenylketone, 2-methyl-
2-morpholino (4-thiomethylphenyl) propane-
1-one, 2-benzyl-2-dimethylamino-1-
Acetophenones such as (4-morpholinophenyl) -butanone; benzoins such as benzoin, benzoin isopropyl ether and benzoin isobutyl ether;
Acyl phosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide; benzyl and methylphenylglyoxyester;

Examples of the latter include benzophenone, ο-
Methyl benzoylbenzoate, 4-phenylbenzophenone, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenylsulfide, acrylated benzophenone, 3,
Benzophenones such as 3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone and 3,3'-dimethyl-4-methoxybenzophenone;

2-isopropylthioxanthone, 2,4
Thioxanthones such as dimethylthioxanthone, 2,4-diethylthioxanthone and 2,4-dichlorothioxanthone; aminobenzophenones such as Michler's ketone and 4,4'-diethylaminobenzophenone; 10-butyl-2-chloroacridone, 2-ethyl Anthraquinone, 9,10-phenanthrenequinone, camphorquinone, and the like.

The silver used as the coating agent of the present invention which is excellent in imparting resistance to discoloration (corrosion) is used for lighting equipment, decorative articles, electronic materials, semiconductor materials, aerospace materials and other industrial materials. In particular, in lighting equipment in which a silver thin film is formed on a light reflecting surface by vapor deposition, slight discoloration (corrosion) occurs.
However, the coating agent of the present invention can be used effectively because the effect is large even if it is present.

The method for coating the silver surface of the coating agent of the present invention, which is excellent in imparting resistance to discoloration (corrosion), includes, for example, flow coater coating, spray coating, dipping coating and the like. Just choose. The thickness of the coating film is suitably 3 to 30 μm, and particularly, discoloration resistance (corrosion)
8 to 15 μm is preferable from the viewpoints of the properties and durability.

[0033]

The present invention will be described more specifically with reference to the following examples and comparative examples. In addition, unless otherwise noted in the examples,
All parts are by weight.

Example 1 Silacoat SCT as a silicone acrylic resin component
-8101 [manufactured by Nitrogen Co., Ltd.], 100 parts, a zirconium complex of 4-methyl-γ-oxo-benzene-butanoic acid as a metal deactivator [CGC1 1930; CIBA
-GEIGY], 1.5 parts, 40 parts of xylene, 60 parts of isopropyl alcohol, and 50 parts of butyl acetate to prepare a coating agent. Next, a spray method is applied to the silver-deposited surface so that the coating film becomes 15 μm, and 130 ° C. ×
Baking was performed for 30 minutes.

Example 2 Silacoat SCT as a silicone acrylic resin component
Except that 100 parts of -1101 [produced by Nitrogen Co., Ltd.] and 10 parts of a zirconium complex of 4-methyl-β-oxo-benzene-propanoic acid were used as a metal deactivator in the same manner as in Example 1. An evaporated silver film having a cured coating film was obtained.

Example 3 Silacoat SCT as a silicone acrylic resin component
1101 [manufactured by Nissan Corporation] 70 parts, MS51SG
1 [Mitsubishi Chemical Corporation] was used, except that 30 parts were used, to obtain an evaporated silver film having a cured coating film in the same manner as in Example 1.

Example 4 UVHC-8553 as a silicone acrylic resin component
[Toshiba Silicon Corporation] 100 parts, Irgacure 184 [CIBA-GEIGY] as a reaction initiator
3 parts, 4-methyl-γ-oxo- as a metal deactivator
Zirconium complex of benzene-butanoic acid [CGC11
930 [manufactured by CIBA-GEIGY] 2 parts, xylene 5
A coating agent was prepared by mixing 0 parts, 40 parts of N-butanol and 60 parts of butyl acetate. Next, a coating method is applied to the surface of the deposited silver by a spray method so that the coating thickness becomes 15 μm.
Dried for 5 minutes. Further, using a 120 w / cm high-pressure mercury lamp (manufactured by Eye Graphic Co., Ltd.) in the atmosphere, the lamp height was 15
Irradiation with ultraviolet light was performed at a conveyor speed of 30 m / min. to obtain a deposited silver film having a cured coating film.

Comparative Example 1 Silacoat SCT as a silicone acrylic resin component
-8101 [manufactured by Nissan Corporation] 100 parts, xylene 4
0 parts, isopropyl alcohol 60 parts, butyl acetate 50
Parts by weight to prepare a coating agent. Next, a spray method is applied to the silver deposition surface so that the coating film becomes 15 μm,
Baking was performed at 130 ° C. for 30 minutes.

Comparative Example 2 2- (benzothiazolylthio)-as a metal deactivator
An evaporated silver film having a cured coating film was obtained in the same manner as in Comparative Example 1 except that 2 parts of succinic acid [Irgacore 252; manufactured by CIBA-GEIGY] was added.

Comparative Example 3 Silacoat SCT as a silicone acrylic resin component
1101 [manufactured by Nissan Corporation] 70 parts, MS51SG
1 [Mitsubishi Chemical Corporation] 30 parts, 2- (benzothiazolylthio) -succinic acid [Irgacore 252; CIBA-GEIGY] 1.5 parts as a metal deactivator were compared. In the same manner as in Example 1, an evaporated silver film having a cured coating film was obtained.

Comparative Example 4 A deposited silver film having a cured coating film in the same manner as in Comparative Example 1 except that 8 parts of a zirconium complex of 4-methyl-γ-oxo-benzene-butanoic acid was blended as a metal deactivator. I got

The performance was evaluated by the following test. The results are shown in Tables 1 and 2.

(1) Adhesion test: A cut is made from the painted surface to the underlying silver surface so that 100 squares of 1.0 mm square can be formed, and a cellophane tape is closely adhered to the cut and vigorously peeled off. Represents the remaining number of tetsumoku.

(2) Heat resistance test: The deposited silver film having the cured coating film was left in a gear oven type heating furnace (manufactured by Satake Rikagaku Kikai Co., Ltd.) at 140 ° C. for 200 hours, and the adhesion and discoloration (yellowing) ) The condition was visually observed and evaluated according to the following four grades. A: No discoloration (yellowing) is observed. ○ ‥‥ Discoloration (yellowing) is slightly observed. Δ ‥‥ Discoloration (yellowing) is observed. × ‥‥ Notable discoloration (yellowing) is observed.

(3) Moisture resistance test: 40 ° C., relative humidity 95
% In a constant temperature / humidity bath [manufactured by Takeda Riken Co., Ltd.] for 300 hours, and then left at room temperature for 24 hours. The adhesion and the discoloration (corrosion) of the surface of the deposited silver were evaluated in the following four grades. A: No discoloration (corrosion) is observed. ○ ‥‥ Discoloration (corrosion) is slightly observed. Δ ‥‥ Discoloration (corrosion) is observed. × ‥‥ Significant discoloration (corrosion) is observed.

(4) Hydrogen sulfide gas test: After leaving the sample in a desiccator in which the hydrogen sulfide gas concentration was adjusted to 20 ppm in an atmosphere at 25 ° C. for 150 hours, the adhesion and the surface of the deposited silver surface were measured in the same manner as described above. The degree of discoloration (corrosion) was evaluated.

[0047]

The composition for a silver-coated paint of the present invention has excellent adhesion and durability, and does not discolor (corrosion) even when exposed to a high temperature exceeding 130 ° C., and can be used in such a severe environment. Useful for the application used.

[0048]

[Table 1]

[0049]

[Table 2]

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 7/12 C09D 7/12 Z 183/10 183/10 C23F 11/00 C23F 11/00 C 11/10 11/10

Claims (4)

[Claims] 1. A composition for a silver-coated paint containing a silicone acrylic resin component as a coating base component, wherein a zirconium complex of a carboxylic acid is contained as a silver inactivating component in an amount of 0.01 to 5% by weight in the coating resin. A composition for a silver-coated paint, characterized by comprising: 2. The composition according to claim 1, wherein the zirconium complex of a carboxylic acid is a zirconium complex of a lower fatty acid having a lower alkyl-substituted benzoyl group. 3. The composition according to claim 2, wherein the zirconium complex of a lower fatty acid having a lower alkyl-substituted benzoyl group is a zirconium complex of 4-methyl-γ-oxo-benzene-butanoic acid. 4. The silver-coated paint composition according to claim 1, wherein the silver to be coated is a silver-deposited surface.