JP2000086943A - Dichroic coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dichroic coating composition capable of providing a dichroic coating membrane manifesting excellent dichroism having stability, and useful for a coating product such as a car body by including a specific pigment and vehicle. SOLUTION: This dichroic coating composition contains (A) a vehicle and (B) a silica flake pigment coated with a metal oxide (preferably titanium oxide or iron sesquioxide). Preferably, the composition further contains (C) at least one kind of pigments selected from a brilliant pigment (e.g. an aluminum flake pigment and a mica pigment), and a color pigment. The content of the component B (expressed in terms of solid) is preferably 0.01-30 pts.wt. based on 100 pts.wt. solid of the coating material in the coating composition. The resin for forming the membrane, composing the component A is especially preferably an acrylic resin and a polyester resin. A basic coating membrane is formed by using the coating composition, and a clear top coating membrane is formed on the basic coating membrane to provide a dichroic coating membrane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dichroic coating composition, a method for forming a dichroic coating film, and a coated article coated by the method. More specifically, a paint capable of providing a dichroic coating film that cannot be obtained conventionally by combining a metal oxide-coated silica flake pigment exhibiting calm dichroism and, if necessary, other brilliant pigments and coloring pigments. The present invention relates to a composition, a method for forming a dichroic coating film, and a coated article coated by the method. In addition, since the coating film obtained by the present invention is excellent in calm dichroism and has a high-class feeling, dichroic properties are required for automobile outer panels, outer surfaces of containers for vehicles such as motorcycles, coil coating, home appliance industry, and the like. It is preferably used in painted objects.

[0002]

2. Description of the Related Art Conventionally, to obtain a coating film having dichroism,
A high chroma durable paint comprising a liquid polymer paint medium and a plurality of interference platelets dispersed in the liquid medium, wherein the platelets are each provided with a metal reflector having first and second surfaces. Wherein said platelets have an aspect ratio of at least 2: 1 with respect to the longest planar dimension of the plane parallel to each layer plane and the thickness of the platelets in each layer plane. A polymer vehicle paint, wherein the plate has a maximum dimension of about 2 to 200 microns on any surface, is described in JP-A-9-508172.

[0003]

The above-mentioned interference platelet has two
It is used as a very good material from the viewpoint of expressing color properties. However, although very dynamic dichroism is developed, it is hard to say that it is calm dichroism.
In order to exhibit dichroism, strict quality control is required when manufacturing interference platelets, and an increase in cost cannot be avoided.

The inventors of the present invention have conducted intensive studies in view of the above problems. As a result, when a metal oxide-coated silica flake pigment and a vehicle are contained in a coating composition, excellent dichroism with calmness is exhibited. The inventors have found that a dichroic coating film can be obtained, and have completed the present invention.

The present invention relates to a dichroic coating composition capable of obtaining a coating film exhibiting excellent dichroism, a method for forming a dichroic coating film, and preferably the outer surface of an automobile body / part or container coated by the method. The purpose is to provide painted objects such as

[0006]

That is, the present invention provides a dichroic coating composition characterized by containing the following (1) and (2). (1) vehicle, and (2) silica flake pigment coated with metal oxide

Another object of the present invention is to provide a dichroic coating composition containing the following (1) to (3). (1) vehicle, (2) silica flake pigment coated with metal oxide, and (3) at least one pigment selected from glittering pigments or coloring pigments

In one embodiment of the present invention, the metal oxide-coated silica flake pigment is present in an amount of 0.01 to 30 parts by weight based on 100 parts by weight of paint solids. The present invention provides a water-soluble coating composition.

The present invention also provides, as an embodiment, a dichroic coating composition characterized in that the metal oxide-coated silica flake pigment is coated with titanium dioxide or diiron trioxide.

In another embodiment of the present invention, the glitter pigment is an aluminum flake pigment, a mica pigment,
A dichroic paint composition characterized by being at least one selected from graphite pigment, alumina flake pigment, metal titanium flake, stainless flake, plate-like iron oxide, phthalocyanine flake or metal-plated glass flake. is there.

Further, as an embodiment of the present invention, there is provided a method for forming a dichroic coating film, which comprises forming a clear top coat coating film after forming a base coat film with the dichroic coating composition on an object to be coated. It provides a method.

The present invention also provides, as an embodiment, a method of forming a clear coat of the above-mentioned dichroic coating composition on a printing ink-formed substrate, or a method of forming a clear coating with a dichroic coating composition on a substrate. An object of the present invention is to provide a method for forming a coating film, which comprises forming a printing ink layer after forming a coat.

Further, the present invention provides, as an embodiment, a coated article characterized in that a coating film is formed by the above-described coating film forming method.

Further, the present invention provides, as an embodiment, a coated object characterized in that the object to be coated is an automobile body / part or an outer surface of a container.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail.

"(1) Vehicle" (1) used in the present invention
The vehicle contains at least one pigment selected from (2) a metal oxide-coated silica flake pigment and, if necessary, (3) a glitter pigment or a coloring pigment. And a crosslinking agent.

Examples of the coating film forming resin constituting the vehicle include an acrylic resin, a polyester resin, an alkyd resin, a fluororesin, and the like. In particular, an acrylic resin and a polyester resin are preferably used. Usually, it is used after being mixed with a crosslinking agent such as an amino resin or a blocked polyisocyanate compound. Also, these resins are
Not only one type but also two or more types can be used in combination. Alternatively, a thermoplastic resin such as a thermoplastic acrylic resin that can be cured by drying at room temperature, a two-component urethane resin, or a silicone resin can be used.

In the present invention, when used as a clear coating composition for the outer surface of a container, the thermosetting type may be any of known acrylic resins and polyester resins.
Epoxy resin or a combination thereof, melamine resin, benzoguanamine resin, urea resin, etc. or a combination thereof as a cross-linking agent, as an ultraviolet-curable type, a solvent-free or organic solvent-diluted ultraviolet radical-curable resin composition Products, ultraviolet cation-curable resin compositions, and mixed resin compositions thereof.

The above-mentioned ultraviolet radical-curable resin composition is obtained by blending a known material having an acrylate group, a methacrylate group, an aryl group or the like capable of radical polymerization with an ultraviolet radical polymerization initiator such as allyl ketone. .

The above-mentioned ultraviolet cationically curable resin composition is obtained by blending an ultraviolet cationic polymerization initiator such as a sulfonium salt with a known material having a cationic etherifying cyclic group such as an epoxy group and an oxetane group, a vinyl ether group and the like. Is mentioned.

When used as a clear coating composition for the outer surface of a container in the present invention, the formed film preferably has a glass transition temperature of 70 ° C to 150 ° C, more preferably 80 ° C to 120 ° C. Solvent-type, water-soluble, and water-dispersion type resins having a temperature of ° C can be given.

The glass formed by the vehicle component of the clear coating composition for the outer surface of the container has a glass transition temperature of 70.
When the temperature is lower than ° C, sufficient hardness of the coating film cannot be obtained, and the coating film is easily damaged, and abnormalities such as whitening of the coating film and blisters are easily caused by heat treatment such as sterilization. On the other hand, when the glass transition temperature exceeds 150 ° C., the elongation of the coating film decreases, and it becomes impossible to follow the processing of the can.

<Blending Ratio> The blending ratio of the coating film forming resin and the crosslinking agent is 90 to 90% in terms of solid content.
It is 50% by weight, preferably 85-60% by weight, and the crosslinking agent is 10-50% by weight, preferably 15-40% by weight. If the crosslinking agent is less than 10% by weight (the resin for forming a coating film exceeds 90% by weight), the crosslinking in the coating film is not sufficient.
On the other hand, if the cross-linking agent exceeds 50% by weight (the resin for forming a coating film is less than 50% by weight), the storage stability of the coating composition is reduced and the curing speed is increased.

"(2) Metal oxide-coated silica flake pigment" The metal oxide-coated silica flake pigment used in the present invention is flaky silica (silicon dioxide) coated with a metal oxide, and has a thickness of the substrate. Is preferably 300 to 500 nm, more preferably 400 to 450 nm, and the major axis is preferably 5 to 60 μm, more preferably 10 to
40 μm. The metal oxide to be coated is iron oxide (iron monoxide or diiron trioxide) or silicon dioxide flake coated with titanium dioxide. The thickness of the coating layer is 50 to 1
20 nm is preferred, and more preferably 60 to 120 nm.
It is. The metal oxide-coated silica flake pigment exhibits calm dichroism.

"Glitter pigment" As the glitter pigment used in the present invention, those conventionally used for paints are conventionally used. For example, aluminum flake pigments (leafing type, non-leafing type), colored aluminum flake pigments, Mica pigment (titanium dioxide coated mica,
Colored mica, metal plated mica), graphite pigment,
Alumina flake pigment, metal titanium flake, stainless flake, plate-like iron oxide, phthalocyanine flake, metal-plated glass flake and the like can be mentioned.

"Coloring pigment" The coloring pigment used in the present invention includes:
Conventionally used for paints are used,
Examples of the organic pigment include an azo lake pigment, a phthalocyanine pigment, an indico pigment, a berylen pigment, a quinophthalone pigment, a dioxazine pigment, a quinacridone pigment, an isoindolinone pigment, a metal complex pigment, and the like. Examples of the inorganic pigment include, for example, graphite, yellow iron oxide, red iron oxide, titanium dioxide, fine particle titanium dioxide, and the like. The addition amount of the coloring pigment can be arbitrarily set in accordance with the hue as long as the coating film retains dichroism.

The metal oxide-coated silica flake pigment used in the present invention is used in an amount of 0.0
It is preferably from 1 to 30 parts by weight of solid content. 0.01
When the amount is less than the solid content part, it is difficult to obtain a dichroic coating film, and when the amount exceeds 30 solid content parts, a smooth coating film is difficult to be selected and various properties required for the dichroic coating are obtained. In addition, the storage stability of the paint may be affected. More preferably, when a color is formed in a complex with the hue of the base (the dichroic coating film has no base hiding property;
In the case of coating 2 bake), 0.1 to 20 parts by weight of solid content, when the color is not complexed with the hue of the base (the dichroic coating film has a base concealing property; In this case, 2 coats and 1 bake) are 0.5 to 20 parts by weight of solid content. When the object to be coated is the outer surface of the container, the coating composition of the present invention is applied to the object to be printed on which the printing ink is to be formed on the object to be printed on which the label notation, pattern, and the like are formed by the printing ink, or on the opposite surface. Therefore, the same compounding amount as in the case of forming a color combined with the above-mentioned hue of the base is preferable.

When the (2) metal oxide-coated silica flake pigment used in the present invention is used in combination with at least one pigment selected from (3) brilliant pigments or coloring pigments, the weight mixing ratio is (2) / (3) = 99/1 to / is preferable, and 90/10 to 50/50 is more preferable.
The weight mixing ratio of the brilliant pigment / colored pigment is 99/1 to 1 /
99 is preferable, and they can be combined so as to obtain a desired color tone in this range.

"Solvent" The dichroic coating composition of the present invention is provided in a form in which the above essential components are usually dissolved and dispersed in a solvent. The solvent may be any one that dissolves and disperses the vehicle, and may be used as an organic solvent type, a non-aqueous dispersion type, an aqueous solution type, or an aqueous dispersion type. Therefore, it is preferable to use an aqueous system. In the case of an aqueous system, an appropriate amount of a hydrophilic organic solvent may be contained. Examples of the organic solvent include hydrocarbons such as toluene and xylene, ketones such as acetone and methyl ether ketone, esters such as ethyl acetate, cellosolve acetate, and butyl cellosolve, and alcohols.

"Other Additives" The dichroic coating composition of the present invention comprises, in addition to the above essential components, an extender pigment, an anti-settling agent, a curing catalyst, an ultraviolet absorber, an antioxidant, a leveling agent, and a silicone. And a surface conditioner such as an organic polymer, a sagging agent, a thickener, a defoaming agent, a lubricant, a crosslinkable polymer particle (microgel), and the like can be appropriately added. The performance of paints and coatings can be improved by blending these additives at a ratio of 5 parts by weight or less based on 100 parts by weight of the vehicle (based on solid content).

<Anti-settling agent> As the anti-settling agent, polyamide wax which is a lubricating dispersion of aliphatic amide and polyethylene wax which is a colloidal dispersion mainly composed of polyethylene oxide are preferable.

The first method for forming a dichroic coating film of the present invention is characterized in that after forming a base coat film with the above-described dichroic coating composition of the present invention, a top coat coating film with a clear coating is formed. The present invention provides a coating system (I) in which (2) a metal oxide-coated silica flake pigment is contained in a base coat.

The second method of forming a dichroic coating film of the present invention is characterized in that after forming a base coat film with the dichroic coating composition of the present invention, a top coat film with a clear coating is formed. A coating system comprising a base coat containing at least one pigment selected from (2) a metal oxide-coated silica flake pigment and (3) a bright pigment or a coloring pigment. Is provided.

The third method of forming a dichroic coating film of the present invention preferably comprises, for the outer surface of the container, (2) a metal oxide-coated silica flake pigment and, if necessary, (3) a glitter pigment or a coloring pigment. A dichroic coating film forming method characterized by forming a topcoat coating film with a dichroic clear paint containing at least one selected pigment in combination,
A coating system (III) is provided.

"Coating (substrate)" The coating material (substrate) of the dichroic coating composition and the dichroic coating film formed by the dichroic coating film forming method of the present invention may be iron, aluminum, copper or the like. Metals such as alloys; inorganic materials such as glass, cement, and concrete; polyethylene resin, polypropylene resin, ethylene-vinyl acetate copolymer resin, polyamide resin, acrylic resin, vinylidene chloride resin, polycarbonate resin, polyurethane resin, epoxy Resins such as resins and plastic materials such as various FRPs; natural and synthetic materials such as wood and fiber materials (paper, cloth, etc.).

The coating composition is applied to the substrate to be coated directly or through an undercoating film. In the case of coating the body and parts of an automobile, it is preferable that a chemical conversion treatment, an electrodeposition coating, an intermediate coating and the like are applied in advance. preferable.

The dichroic coating composition and the dichroic coating film forming method of the present invention can be preferably used for a cylindrical object such as a beverage can as a substrate (substrate) exhibiting dichroism. . Aluminum, iron, or tin
A metal can container using a steel material plated with chromium or nickel, and a paper container can be used. The metal container has a bottomed can body,
There are a two-piece can formed from a canopy and a three-piece can formed from a can body, canopy, and bottom lid. In addition, there are art cans in which food such as confectionery is put. The two-piece can, the three-piece can, and the art can all have their outer surfaces coated with a white base coat or directly with a label or pattern printed with printing ink.
On top of that, a coating film is formed with a clear coating using the dichroic coating composition of the present invention for the purpose of developing dichroism, preventing corrosion of the substrate and protecting the printing ink layer.

The film can also be used for a metal can laminated with a film. The film used for the lamination is preferably a thermoplastic film, for example, an olefin resin film such as a polyethylene resin or a polypropylene resin, or polyvinyl chloride. Resin, polyvinyl chloride / vinyl acetate copolymer resin, polyvinyl resin film such as polyvinylidene chloride resin, polyethylene terephthalate resin,
Examples thereof include a polyester resin film such as a polyethylene naphthalate resin, a polystyrene resin film, a polyamide resin film, and a polyimide resin film. If necessary, corona-treat the resin film surface,
Processing such as chemical processing and flame processing can also be performed.

"Coating film forming method (coating system I or II)" 2
The color coating composition is applied on a substrate to form a dichroic coating film of a base coat, and at least one clear coating is applied as a top coat on the obtained dichroic coating film. It is suitably used for automobile bodies and parts.

<Base coat: dichroic coating> In the case of using a substrate coated with an undercoat with an intermediate coating or the like,
A dichroic coating composition is applied on the base coat by a wet-on-wet (W / W) method or a bake-on-wet (B / W) method. The W / W method is a method in which an undercoating film is formed and then dried by air drying or the like, and then applied in an uncured or semi-cured state. The B / W method is a method in which the undercoating film is applied after baking. It is. The coating method is not particularly limited, but a spray method, a roll coater method and the like are preferable. The dry film thickness of the dichroic coating film is preferably 5 to 50 μm, and 10 to 30 μm
Is more preferred.

<Topcoat: Clear Coating> At least one topcoat clear coating is formed on the basecoat coating. If the base coating composition contains a large amount of brilliant pigments, applying two or more layers of the clear varnish improves the brilliancy on the surface. The clear coating may be any of those commonly used for topcoats. The application of the clear paint on the coating film of the present invention can be performed by a wet-on-wet (W / W) method. When the clear paint is applied a plurality of times, it may be baked after the final clear coat is applied, and may be in a W / W, plate or semi-cured state at the stage of forming the lower clear coat. The baking temperature after clear coating may be 120 to 160 ° C. The dry film thickness of the clear coating film is preferably from 10 to 80 µm, more preferably from 20 to 50 µm.

The composition of the clear paint is (i) a mixture of at least one thermosetting resin selected from acrylic resins, polyester resins, fluororesins and modified resins thereof and the above-mentioned crosslinking agent, or (Ii) A vehicle comprising a carboxyl group-containing polymer and an epoxy group-containing polymer can be used. From the viewpoint of acid rain resistance and to increase the difference in solubility with the base coat paint, (ii) a carboxyl group-containing polymer and A composition containing a vehicle comprising an epoxy group-containing polymer (see Japanese Patent Publication No. H8-19315) is preferable. Further, as a preferable composition, additives such as a pigment, a modifier, an ultraviolet absorber, a leveling agent, a dispersant, and an antifoaming agent can be added to the transparent resin as long as the transparency is not impaired.

"Method for forming coating film (coating system III)" A dichroic clear coating film is formed as a top coat on a printing ink-forming substrate by using the dichroic coating composition. A clear coating for protection may be applied on the obtained two-color clear coating film. It is suitably used for the outer surface of a container and the like. The coating method is not particularly limited, but a spray method, a roll coater method and the like are preferable. Dry film thickness of the dichroic clear coating film is 1 to 10 μm
Is preferred.

(A) A direct or thermosetting or UV-curable resin-based base coating film is formed on an object to be coated which has been subjected to pre-coating, and (B) a pattern is formed with a thermosetting or UV-curable resin ink. Labeling is performed, and (C) a thermosetting or ultraviolet curable resin dichroic clear coating film is formed. The thermosetting or ultraviolet curable resin of the above (B) and (C),
Any combination can be used. However, the same type of resin is preferably used for the ink layer and the clear coating film. The dichroic clear coating film (C) may be formed in a stripe shape or the like on a part of the outer surface of the container, and an ordinary non-dichroic clear coating film may be formed on the remaining part or the entire surface. The white base coating film / ink layer / clear coating film is preferably applied by a wet-on-wet method.

The two-piece can is formed into a can body, preferably after forming a coating film on the outer surface with a dichroic clear, and then forming a coating film on the inner surface with a coating for the inner surface. In a three-piece can, a sheet before forming into a can is formed, preferably after forming an inner coating film using an inner coating material, forming a coating film on the outer surface with a dichroic clear, and then forming into a can body. For both two-piece and three-piece cans, a coating film can be formed in the reverse order.

In the case of a laminated can, a dichroic clear coating film can be formed. In a two-piece laminated can, a transparent thermoplastic resin film is dispersed on one side of a metal plate and a white pigment is dispersed on the opposite side. The applied thermoplastic resin film is coated with an adhesive if necessary, dried, and then thermocompression-bonded.
A metal plate having a film laminated on both sides is formed into a two-piece can body such that a transparent thermoplastic resin film becomes the inner surface of the can, and the outer surface thereof is formed in the same manner as the two-piece can and the three-piece can (B). ) Designing and labeling with a thermosetting or ultraviolet curable resin ink, and (C) forming a dichroic clear coating film of thermosetting or ultraviolet curable resin.

In a three-piece laminate can, a thermosetting or ultraviolet-curable resin dichroic clear coating film is formed on one surface of a thermoplastic resin film, and a pattern is formed on the other surface with a thermosetting or ultraviolet-curing resin ink. After labeling and drying, apply a thermosetting or UV-curable resin adhesive, and after drying, if necessary, form a thermosetting or UV-curable resin-based white base coating film, so that the ink layer side is in contact with the can. On the other side (the inner surface side of the can), another transparent thermoplastic resin film is thermocompression-bonded to each other to form a can body. Painted cans or plates, if thermosetting resin system, hot air oven,
10 seconds to 10 seconds in the range of 100 ° C to 250 ° C by infrared lamp, induction heating, etc., or a combination of these.
It is baked separately. In the case of a UV-curable resin system, after the solvent is removed if necessary, a high-pressure mercury lamp, metal halide lamp, xenon lamp or the like is irradiated for 0.01 second to 1 minute to cure.

[0048]

EXAMPLES Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In addition, the compounding amount represents a weight part unless there is particular notice.

"Examples 1 to 16 and Comparative Examples 1 to 4 (automobile coating system)" Preparation of substrate to be coated Dull steel plate (length 300 mm, width 100 mm and thickness 0.
8 mm) with a zinc phosphate treating agent (“Surdyne SD200”).
0, manufactured by Nippon Paint Co., Ltd.), and then the cationic electrodeposition paint (“Power Top U-50”, manufactured by Nippon Paint Co., Ltd.) was dried to a dry film thickness of 25 μm. I painted. Next, after baking at 160 ° C. for 30 minutes, in the coating method 2 coats 1 bake method (2C1B), the intermediate coat (“Olga S-90 Sealer Gray (L =
60) "manufactured by Nippon Paint Co., Ltd., and an intermediate coating (" Olga S-90 Sealer Gray (L = 20) or (L = 6) "in the three-coat two-bake method (3C2B).
0) ", manufactured by Nippon Paint Co., Ltd.)
And sprayed at 140 ° C. for 30 minutes to form an intermediate coating film.

2. Preparation of dichroic coating composition Acrylic resin (styrene / methyl methacrylate / ethyl methacrylate / hydroxyethyl methacrylate /
Methacrylic acid copolymer, number average molecular weight about 20,000
0, hydroxyl value 45, acid value 15, solid content 50% by weight);
A melamine resin (trade name, "Uban 20SE", manufactured by Mitsui Chemicals, Inc., solid content 60% by weight) was mixed with a vehicle obtained at a solid content weight ratio of 80:20. A coated silica flake pigment (silica flake A: diiron trioxide-coated silica flake pigment, silica flake B: titanium dioxide-coated silica flake pigment), (B) brilliant pigment, and (C) coloring pigment are blended in the proportions shown in Table 1. did. Subsequently, the mixture was stirred and mixed with an organic solvent (weight ratio of toluene / xylene / ethyl acetate / butyl acetate = 70/15/10/5) by a dissolver so as to obtain a proper coating viscosity.
A dichroic coating composition was prepared. Note that (B) the glitter pigment is an aluminum flake pigment (“Aluminum paste MH8
801 "(manufactured by Asahi Kasei Corporation), colored aluminum flake pigment (" Friend Color F500BL ", manufactured by Showa Denko KK), and colored mica pigment (" Iriodin 502WI ").
I ", manufactured by Merck & Co., Ltd., interference mica pigment (" Iriodin 2 "
17WII ", manufactured by Merck Co., Ltd., graphite pigment (" Graphtan 7525 ", manufactured by Ciba Specialty Chemicals Co., Ltd.), fine particle titanium oxide pigment (" Taipaek TTO-55B ", manufactured by Ishihara Sangyo Co., Ltd.), alumina flake Pigment A (alumina flake pigment coated with iron trioxide, manufactured by Merck) and alumina flake pigment B (alumina flake pigment coated with titanium dioxide, manufactured by Merck) were used.

3. Formation of Dichroic Coating Film The above-mentioned dichroic coating composition was applied on the surface to be coated of the substrate to a dry film thickness of 1%.
The coating was performed so as to be 5 μm. The coating is performed by an electrostatic coating machine ("A
auto REA ", manufactured by Landsberg Gemma Co., Ltd.) at an atomization pressure of 2.8 kg / cm2. The atmosphere in the booth during coating was maintained at a temperature of 25 ° C. and a humidity of 75%. After coating, set for 3 minutes and dry paint to a dry film thickness of 35μm
Paint, set at room temperature for 10 minutes,
Baking at a temperature of 140 ° C. for 30 minutes. The hiding power and chroma of the obtained coating film were evaluated by the following evaluation methods. Table 1 shows the results. The clear paint free of metal oxide-coated silica flakes used was (1) an acrylic / melamine resin clear paint (trade name: "Super Luck 0-130 Clear", manufactured by Nippon Paint Co., Ltd.) or (2) There are two types of clear coatings ("Macflow 0-520 Clear", manufactured by Nippon Paint Co., Ltd.) comprising a blend of a carboxyl group-containing polymer and an epoxy group-containing polymer.

Evaluation Method Dichroism When the test piece after forming the coating was viewed from almost right above (A),
When viewed at an overhead angle of about 15 degrees with respect to the test piece (B), the color of the coating film was visually evaluated. (A), (B)
Are clearly different from each other, and those with calm dichroism are ◎, and those with different colors in (A) and (B) are ○, (A) and (B) respectively. Those that could not be said to have different colors were evaluated as x.

[0053]

[Table 1]

"Examples 17 to 22, Comparative Examples 5 to 7 (Container outer surface coating system)" Production Example 1 "Preparation of thermosetting clear coating material (A-1) for outer surface of metal can" Acrylic resin ("Dianal SC-1170 ",
50 parts of Mitsubishi Rayon Co., Ltd., non-volatile content 60%, methyl-n-butylated benzoguanamine resin ("Niclac S"
B-355 ", manufactured by Sanwa Chemical Co., Ltd., nonvolatile content 75
%) 26.7 parts, an acid catalyst ("Catalyst 6000",
0.1 part, manufactured by Mitsui Chemicals, Inc., butyl cellosolve 23.
Two parts were mixed and made uniform to obtain a thermosetting clear coating material (A-1) having a nonvolatile content of 50%.

Production Example 2 "Preparation of Ultra Radical Curable Clear Coating (A-2) for Metal Can Exterior" Urethane acrylate ("UA-3
06H ", manufactured by Kyoeisha Chemical Co., Ltd.), 40 parts, neopentyl glycol monoacrylate monobenzoate 7.5
Part, ultraviolet radical polymerization initiator (“IRGACURE 50
1 ", Ciba-Geigy Corporation) 2.5 parts, ethyl acetate 5
0 parts were mixed and made uniform to obtain an ultraviolet radical-curable clear coating material (A-2) having a nonvolatile content of 50%.

Production Example 3 "Preparation of thermosetting white base coat" 300 parts of epoxy resin-modified acrylic resin ("WCB-501", manufactured by Mitsui Chemicals, Inc., nonvolatile content 70%), titanium oxide ("Typek CR- 97 ", manufactured by Ishihara Sangyo Co., Ltd.), 3
00 parts and 230 parts of butyl cellosolve were sufficiently dispersed in a sand grind mill, and 170 parts of butylated benzoguanamine (“Symel 1128”, manufactured by Mitsui Cytec Co., Ltd., nonvolatile content 70%) was added to obtain a thermosetting white base coat. Was.

Production Example 4 "Preparation of thermosetting printing ink" 500 parts of alkyd resin ("Gorcelac 223", manufactured by Nippon Synthetic Chemical Industry Co., Ltd., nonvolatile content: 70%) and 290 parts of carbon black were mixed with 3 parts.
This roll mill sufficiently disperses and methylated melamine (“M
X-035 ", manufactured by Sanwa Chemical Co., Ltd., non-volatile content 70
%) Was added to obtain a thermosetting ink.

Production Example 5 "Preparation of UV-curable printing ink" 2-hydroxy-
300 parts of 3-phenoxypropyl acrylate, 370 parts of pentaerythritol tetraacrylate, 70 parts of vinylpyrrolidone, 70 parts of polyoxyethylene sorbitan monooleate, and 150 parts of ultramarine blue (blue pigment) were sufficiently dispersed by a three-roll mill, To the mixture was added 40 parts of 2-methylpropiophenol to obtain an ultraviolet curable ink.

Example 17 (2-piece can) The heat-curable clear paint for the outer surface of a metal can (A-
1) For 100 parts, 5 parts of silica flake A (described above),
5 parts of butyl cellosolve was added and mixed well with a disper to obtain a thermosetting silica flake-containing clear paint (C-1) for the outer surface of a metal can. Subsequently, a painted can was prepared by the following method. The white base coat of Production Example 3 was applied to the outer surface of a 350 ml aluminum can treated with chromic acid using a roll coater so that the dry film thickness was about 7 μm, and baked in a drying oven at 200 ° C. for 1 minute. in addition,
The thermosetting printing ink of Production Example 4 was printed by an offset printing machine so that the dry film thickness was about 1 μm, and immediately the thermosetting silica flake-containing clear paint for the outer surface of a metal can (C)
-1) was applied using a roll coater so that the dry film thickness was about 5 μm, and baked in a drying furnace at 200 ° C. for 1 minute.
After cooling, an epoxy-acrylic resin-based water-based paint is applied on the inner surface by spraying so as to have an average dry film thickness of about 5 μm.
Baking was performed at 00 ° C. for 2 minutes. Table 2 shows the performance of the outer coating film.

Example 18 (3-piece can) The thermosetting clear paint for the outer surface of a metal can (A-
1) To 100 parts, 10 parts of silica flake A and 10 parts of butyl cellosolve were added and mixed well with a disper to obtain a thermosetting silica flake-containing clear coating material for metal can outer surface (C-2). Subsequently, a three-piece can coated plate was prepared by the following method. One side of a nickel-plated steel sheet is coated with a solvent type epoxy / phenol resin paint for inner surface of about 8 μm in dry thickness by a roll coater, baked in a drying oven at 200 ° C. for 10 minutes, and then the thermosetting type of Production Example 3 on the other side. Was coated with a roll coater so that the dry film thickness was about 7 μm, and baked in a drying oven at 200 ° C. for 10 minutes. Then, the thermosetting printing ink of Production Example 4 was printed by an offset printing machine so as to have a dry film thickness of about 1 μm, and immediately, the thermosetting silica flake-containing clear paint (C- 2) was applied using a roll coater so that the dry film thickness was about 5 μm, and baked in a drying oven at 200 ° C. for 8 minutes. Table 2 shows the performance of the outer coating film.

Example 19 (2-piece can) The heat-curable clear paint for the outer surface of a metal can (A-
1) 20 parts of silica flake A and 20 parts of butyl cellosolve were added to 100 parts, and the mixture was sufficiently mixed with a disper to obtain a thermosetting silica flake-containing clear paint for metal can outer surface (C-3). Subsequently, a painted can was prepared by the following method. The thermosetting printing ink of Production Example 4 was printed on the outer surface of a 350 ml aluminum can treated with chromic acid using an offset printing machine so that the dry film thickness was about 1 μm, and immediately the thermosetting silica flake-containing metal can was used. An outer surface clear paint (C-3) is applied with a roll coater so that the dry film thickness is about 5 μm, and dried in a drying oven for 200 hours.
After baking for 1 minute and cooling, the inner surface was spray-coated with an epoxy-acrylic resin-based water-based paint so as to have an average dry film thickness of about 5 μm, and then baked at 200 ° C. for 2 minutes. Table 2 shows the performance of the outer coating film.

Example 20 (3-piece laminated can) 5 parts of silica flake A was added to 100 parts of the ultraviolet-curable clear coating for metal can outer surface (A-2) of Production Example 2,
Ethyl acetate (5 parts) was added and mixed well with a disper to obtain a UV-curable silica flake-containing clear paint for metal can outer surface (C-4). This was coated on one side of a corona-treated polyethylene terephthalate film with a dry film thickness of about 1 μm.
m with a gravure roll coater to obtain 50 m
After the organic solvent was blown off by blowing hot air at a temperature of 20 ° C. for 20 seconds, it was irradiated and cured at a speed of 15 m / min under a condensing high pressure mercury lamp “HAN-60NL” (160 W / cm, manufactured by Nippon Battery). . On the opposite side of the film, the ultraviolet curable printing ink of Production Example 5 diluted to 50% solids with ethyl acetate was printed with a gravure printing machine to a dry film thickness of about 1 μm, and exposed to warm air at 50 ° C. for 20 seconds. After the organic solvent was blown off, irradiation was performed at a speed of 10 m / min under a condensing high-pressure mercury lamp “HAN-60NL” (160 W / cm, manufactured by Nippon Battery) to cure.
On top of this, an epoxy resin-based solvent-based adhesive is applied, and 50
After applying hot air of 20 ° C. for 20 seconds, the coated surface of the solvent-type epoxy resin-based adhesive was applied to the nickel-plated steel sheet, and the sheet was thermocompressed at 180 ° C. by passing between nip rolls at the same temperature and 20 kg / cm. Table 2 shows the performance of the outer coating film.

Example 21 (3-Piece Laminated Can) The ultraviolet-curable silica flake-containing clear paint (C-4) for the outer surface of a metal can containing the ultraviolet-curable silica flake of Example 20 was applied to one surface of a polyethylene terephthalate film subjected to corona treatment to a dry film thickness of about 1 mm.
paint with a gravure roll coater to a thickness of
After the organic solvent was blown off by blowing hot air of 0 ° C. for 20 seconds, the condensing high pressure mercury lamp “HAN-60NL” (160 W / cm,
Irradiation at a speed of 15 m / min. The opposite surface of the film was coated with the ultraviolet-curable printing ink of Production Example 5 diluted to 50% solids with ethyl acetate using a gravure printing machine so as to have a dry film thickness of about 1 μm.
Was blown for 20 seconds to blow off the organic solvent, and then irradiated and cured at a speed of 10 m / min under a condensing high-pressure mercury lamp “HAN-60NL” (160 W / cm, manufactured by Nippon Battery). Paint an epoxy resin solvent adhesive on top of this,
After applying hot air at 50 ° C. for 20 seconds, the thermosetting white base coat of Production Example 3 was applied with a roll coater so as to have a dry film thickness of about 7 μm, and was baked in a drying oven at 200 ° C. for 2 minutes. The coated surface of the solvent-type epoxy resin-based adhesive was applied to the plated steel sheet and thermocompression bonded.
Table 2 shows the performance of the outer coating film.

Example 22 (2-piece can) The thermosetting printing ink of Production Example 4 was printed on the outer surface of a chromic acid-treated 350 ml steel can with an offset printing machine so that the dry film thickness was about 1 μm. And baked in a drying oven at 200 ° C. for 1 minute. Then, the thermosetting silica flake-containing metal can outer surface clear coating material (C-1) of Example 17 was applied in a stripe shape by a gravure coating machine,
It was baked at 200 ° C. for 1 minute in a drying oven. After this,
The thermosetting clear paint for the outer surface of a metal can (A-
1) is applied by a roll coater so that the dry film thickness is about 5 μm on the entire side body, baked in a drying oven at 200 ° C. for 1 minute, and after cooling, an epoxy / acrylic resin-based water-based paint is applied on the inner surface. After spray coating to a thickness of about 5 μm, baking was performed at 200 ° C. for 2 minutes. Table 2 shows the performance of the outer coating film.

Comparative Example 5 (2-Piece Can) The thermosetting silica flake-free metal of the production example 1 was used instead of the thermosetting silica flake-containing metal can outer coating (C-1) of Example 17. Except for using the clear paint for can outer surface (A-1), a paint can is prepared by the method described in Example 17. Table 2 shows the performance of the outer coating film.

Comparative Example 6 (2-Piece Can) Instead of the thermosetting silica flake-containing metal can outer clear coating (C-2) of Example 18, the thermosetting non-metallic can outer surface of Production Example 1 was used. Except for using the clear paint for coating (A-1), a paint can is prepared by the method described in Example 18. Table 2 shows the performance of the outer coating film.

Comparative Example 7 (2-Piece Can) Production Example 2 was used in place of the UV-curable silica flake-containing heat clear paint for metal outer surface (C-3) of Example 19
A coating can is prepared by the method described in Example 17 except that the ultraviolet-curable clear paint (A-2) for the outer surface of a silica flake-free metal can is used. Table 2 shows the performance of the outer coating film.

Evaluation Method Dichroism Evaluation was performed in the same manner as in Examples 1 to 16.

Retort resistance The coated product was allowed to stand in steam at 125 ° C. for 30 minutes, and when the coating film appearance did not change, such as whitening or blistering, it was evaluated as ○. Those which blisters etc. were generated were evaluated as x.

Hardness: Determined according to JIS K5400 using Mitsubishi Uni pencil.

Adhesion According to JIS K5400, cellophane tape was peeled off after cross-cut at 1 mm intervals, and the peeling state of the coating film was observed. The sample without peeling was evaluated as ○, the sample with slight peeling was evaluated as Δ, and the sample with completely peeled was evaluated as ×.

Impact Resistance A drop test was performed in accordance with JIS K5400 under the conditions of a shooting type of 6.35 mm, a load of 300 g, and a height of 30 cm.
も の indicates that there was no cracking or peeling, △ indicates that cracking or peeling occurred, and × indicates that cracking or peeling occurred overall.
Was evaluated.

Paint stability The paint was left in an atmosphere at 40 ° C. for one month, and the state of separation and settling of the pigment was visually evaluated. If there was no separation and sedimentation, ○, if separation and sedimentation occurred slightly, but the initial state was obtained by stirring, and Δ, marked separation and sedimentation occurred.
If the separation / sedimentation could not be resolved even by stirring,
Was evaluated.

[0074]

[Table 2]

From the results shown in Table 2, all of the silica flake-containing clear paints obtained in the examples exhibited a good flip-flop feeling, and satisfied the coating performance required for the clear paint for beverage can outer surfaces. It can be seen that the stability of the paint is also satisfactory.

[0076]

As is clear from the results of Tables 1 and 2,
ADVANTAGE OF THE INVENTION According to this invention, the dichroic coating composition from which the calm and excellent dichroic coating film can be obtained, a dichroic coating film formation method, and the coated material coated by the method can be provided.

[Procedure amendment]

[Submission date] November 10, 1998 (1998.11.
10)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction contents]

When the (2) metal oxide-coated silica flake pigment used in the present invention is used in combination with at least one pigment selected from (3) brilliant pigments or coloring pigments, the weight mixing ratio is (2) / (3) = 99/1 to 40/60 is preferable, and 90/10 to 50/50 is more preferable. The weight mixing ratio of glitter pigment / color pigment is 99/1 to 1
The ratio is preferably 1/99, and they can be combined so as to obtain a desired color tone in this range.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

[Correction contents]

3. Formation of Dichroic Coating Film The above-mentioned dichroic coating composition was applied on the surface to be coated of the substrate to a dry film thickness of 1%.
The coating was performed so as to be 5 μm. The coating is performed by an electrostatic coating machine ("A
auto REA ", manufactured by Landsberg Gemma Co., Ltd.) at an atomization pressure of 2.8 kg / cm2. The atmosphere in the booth during coating was maintained at a temperature of 25 ° C. and a humidity of 75%. After coating, set for 3 minutes and dry paint to a dry film thickness of 35μm
Paint, set at room temperature for 10 minutes,
Baking at a temperature of 140 ° C. for 30 minutes. Of the resulting coating
The dichroism was evaluated by the following evaluation method. Table 1 shows the results.
The metal oxide-coated silica flake-free clear paint used was (1) an acrylic / melamine resin-based clear paint (trade name: “Supper Luck 0-130 Clear”,
Nippon Paint Co., Ltd.) or (2) a clear paint ("Macflow-0-520 Clear", manufactured by Nippon Paint Co., Ltd.) comprising a blend of a carboxyl group-containing polymer and an epoxy group-containing polymer.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J038 CD091 CG001 DA142 DA162 DA172 DB001 DD001 HA446 KA03 KA06 KA08 KA15 KA20 NA01 PB04 PB07 PC02 PC08

Claims (2)

[Claims] 1. A dichroic coating composition comprising (1) a vehicle and (2) a metal oxide-coated silica flake pigment. 2. A dichroism comprising (1) a vehicle, (2) a silica flake pigment coated with a metal oxide, and (3) at least one pigment selected from glittering pigments and coloring pigments. Paint composition.