JPS6211908B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for decorating metal products such as plates, pipes, and processed products. More specifically, a desired portion of a non-conductive film layer formed on the surface of a metal product is removed, a thermosetting resin is electrodeposited on the removed portion to form a coating layer, and the coating layer is formed by electrodepositing a thermosetting resin on the removed portion. The present invention relates to a method for decorating metal products, which comprises pressing a stamping foil onto a film layer.

BACKGROUND ART Decorating methods in which stamping foil is pressed onto the surface of metal, glass, or plastic have been known. Further, Japanese Patent Publication No. 55-6514 proposes a method of printing metal products in which a metal foil of stamping foil is pressed onto a printed surface of a thermosetting resin. However, since all of these are metal foils that are crimped onto molded protrusions or printed thermosetting resin layer protrusions, the metal foils tend to wear out due to friction, etc. It had the disadvantage that it was difficult to maintain its appearance.

In addition, since the metal foil of the stamping foil is heat-pressed onto the thermosetting resin layer in a semi-cured state, the protruding thermosetting resin spreads and protrudes, so the metal foil with fine or narrow characters, designs, etc. There was a limit to how precisely the parts could be crimped together.

The present invention has been made in view of the above-mentioned drawbacks, that is, the method for decorating metal products of the present invention is as follows:
After forming a non-conductive film layer on the surface of the metal product,
A desired portion of the non-conductive film layer is removed according to arbitrary characters, designs, etc. to expose the conductive metal surface, and then a thermosetting resin is electrodeposited on the metal surface. to form a coating layer whose upper surface is lower than the surface of the non-conductive coating layer, and before the coating layer is completely cured, press the metal foil of the stamping foil onto the coating layer with a heated elastic body, It is characterized in that the metal foil of the stamping foil for curing the coating layer is present on the same level as the surface of the non-conductive coating layer on the metal surface, or in a concave portion lower than the surface.

In the present invention, the metal product is a plate, tube, processed product, etc. made of any material such as aluminum, aluminum alloy, copper, copper alloy, etc., and its shape is not particularly limited.

A non-conductive film layer made of a paint film applied to the surface of metal products can be applied to metal products that have been cleaned.
Non-conductive paints containing thermosetting resins such as alkyd resins, acrylic resins, epoxy resins, polyurethane resins, and polyester resins are applied, and conventional painting methods such as spray painting, brush painting, roller painting, and electrodeposition are applied. It is formed by applying a coating method such as painting or electrostatic coating, and then subjecting it to heat treatment. Although the thickness of the coating film is not particularly limited, it is usually 20 to 30 μm. In addition, if the material of the metal product is aluminum or aluminum alloy, a non-conductive film layer can be formed on the surface of the metal product by performing anodizing treatment and sealing treatment in the usual manner. It is possible.
That is, the surface of the metal product is degreased and cleaned with a sodium hydroxide solution, etc., and then heated to a current density of 1.0 in a positive oxide film forming bath consisting of an aqueous solution of sulfuric acid, oxalic acid, sulfuric acid, etc.
Direct current electrolysis at ~1.5 A/dm ² for 20 to 50 minutes, then immersion in a dye solution for dyeing if necessary, followed by boiling and sealing in an aqueous solution of nickel acetate, cobalt acetate, etc. Alternatively, this can be achieved, for example, by performing a steam sealing treatment for 20 to 30 minutes at a steam pressure of about 5 kg/cm ² . The thickness of the anodized pore-sealing layer is not particularly limited, but is usually 8.
~15 μm thick.

A physical cutting method or a laser beam irradiation method is adopted as a method for removing the non-conductive film layer according to desired characters, designs, etc. As for the physical cutting method, diamond bits, ceramic bits, cemented carbide tungsten bits, etc. are selected and applied. In addition, as a method of irradiating with a laser beam, there is a method of irradiating with a YAG laser beam, a CO ₂ gas laser beam, a ruby laser beam, etc., and locally burning out or melting and evaporating the non-conductive film layer to remove it. It is a removal method that has good reproducibility, high precision, and is efficient and suitable for mass production.

A mask made of a material that shields laser beams and has desired characters, designs, etc. opened is applied, the mask is closely attached to the non-conductive film layer of a metal product, and the entire surface of the mask is scanned with a laser beam until it is irradiated. In this case, only the non-conductive film layer corresponding to the opened portion is removed by being irradiated with a laser beam and burned away or melted and evaporated. The material that shields the laser beam varies depending on the type of laser beam, but it is formed of a metal plate, metal foil, metal-containing paint film, etc. The conditions for scanning and irradiating the laser beam vary depending on the type and thickness of the non-conductive film layer, the type of laser beam, etc. For example, in the case of YAG laser, the beam diameter is 50 to 150μ.
mφ, output: 10~40w, feed speed: 200~400mm/
It is possible to remove the non-conductive film layer under conditions of sec.

Furthermore, by using a well-known device that synchronizes original image scanning to read original images such as characters and designs, and laser beam scanning to reproduce and irradiate an image identical to or similar to the original image on the irradiated surface. Therefore, there is no need for the above-mentioned laser beam shielding mask, and desired characters, designs, etc. can be uniformly reproduced on the surface of metal products in the areas where the non-conductive film layer has been removed, quickly and efficiently. .

Thermosetting resins used in the electrodeposition coating of the present invention include anionic alkyd resins, acrylic resins, polyester resins, polyurethane resins, etc.
There are cationic epoxy resins, modified acrylic resins, etc., and one that is suitable for the material of the metal product is selected, and in particular, one that has good adhesion to the metal foil of the stamping foil described later is used.

Electrodeposition coating is performed by first degreasing and cleaning as a pretreatment, and then applying a direct current of 50 to 150V between the poles of the metal product and the stainless steel plate in an electrodeposition coating bath containing an aqueous solution or emulsion of the thermosetting resin. This is applied by the usual method of applying electricity for ~3 minutes, and an electrocoated coating layer is formed only on the conductive metal surface from which the non-conductive coating layer has been removed. The thickness of the coating layer may be such that the metal foil of the stamping foil described below is on the same surface as the surface of the metal product or in a recessed portion lower than the surface.

Stamping foil is a well-known method in which a metal foil such as aluminum or gold is deposited on a base film, or a metal foil such as gold or silver is bonded and a top coat is applied on top of the metal foil. There are metal foils colored in various glittering colors, which can be used arbitrarily.

In order to press the metal foil of the stamping foil onto the coating layer, it must be heated to a temperature of 150 to 200°C when the coating layer is in a semi-cured state and, if necessary, heated to a certain degree of tackiness. The stamping foil may be pressed and bonded to the coating layer using a heated elastic body such as silicone rubber. Further, the semi-cured state is a state in which the coating layer does not deform or spread when it comes into contact with the stamping foil and is pressurized.

In the present invention, since the coating layer is formed in the recesses lower than the surface of the metal product, by applying pressure with a heated elastic body, the metal foil of the stamping foil is removed from the adhesive coating layer present in the recesses. It adheres only to that layer and not to other non-conductive coating layers. or,
At this time, the coating layer does not deform, spread, or protrude, making it possible to precisely and delicately decorate with fine or narrow characters, designs, etc. Further, the metal product having the metal foil crimped thereon as described above is subjected to a dry heat treatment at a temperature of 120 to 200°C for 15 to 30 minutes to strongly adhere the metal foil to the coating layer and to harden the coating layer. Furthermore, if necessary, a top coat made of a transparent thermosetting resin may be applied to the above-mentioned decorated metal product to further improve the abrasion resistance of the metal foil.

The drawings are sectional views of essential parts showing the method of the present invention in its order. In the drawing, 1 is a metal product,
2 is a non-conductive film layer formed on the surface of a metal product, 3 is a conductive metal surface exposed by removing the non-conductive film layer according to characters, designs, etc., and 4 is electrodeposition on the metal surface. The coating layer 5 formed by painting is a metal foil of stamping foil that is press-bonded to the coating layer. still,
Although not shown in the drawings, a top coat may be applied to the surface of the metal foil 5 or the entire surface of the decorated metal product.

As mentioned above, in the present invention, the metal foil can be crimped into the concave portion that is flush with the surface of the metal product or is low, and the metal foil is provided on the protruding portion as in the conventional method, and the metal foil is wear-resistant. Excellent in sex. In addition, by electrocoating a thermosetting resin on a conductive metal surface to form a coating layer,
Unlike the invention of Publication No. 55-6514, in which a coating layer is provided by a printing method, there is no need for alignment of printing. Furthermore, since the coating layer is formed on the same surface as the surface of the metal product or in low recesses, the coating layer will not be deformed when the metal foil of the stamping foil is pressed, making it possible to print delicate letters, designs, etc. Metal foil can be used to precisely decorate metal products.

The present invention is applicable to various metal products, but is particularly applicable to metal products used as containers for cosmetics, and is an extremely beautiful and durable container with an exterior appearance such as glittering letters and designs. It provides:

Next, examples of the present invention will be described. Note that the present invention is not limited to only what is described in the examples.

Example 1 A cap made of aluminum (purity 99.8wt%)
Degrease and wash with 2wt% sodium hydroxide aqueous solution,
It was immersed in an electrolytic bath of 18 wt % sulfuric acid aqueous solution at a temperature of 23° C. and subjected to direct current electrolysis at a current density of 1.5 A/dm ² for 30 minutes to form an anodic oxide film with a thickness of 10 μm. Next, after immersing in a deep blue dye solution for 20 minutes, the liquid temperature
The holes were sealed by immersion in a 5 wt% nickel acetate solution at 95°C for 20 minutes. Next, a mask made of a polished stainless steel or copper alloy thin plate with the letter A in the opening is attached to the top of the cap.
Irradiation surface of this mask: 20mmφ Output: 36~52J/
CO ² _gas laser beam (wavelength 10.63
The anodized sealing layer marked with the letter A was removed by irradiating with .mu.m) to expose the conductive aluminum metal surface. Next, this cap is immersed in an emulsion bath of acrylic anion type electrocoating resin with a liquid temperature of 23℃ and a non-volatile content of 15%, and a 100V DC current is applied between the two electrodes, with the cap as the anode and the stainless steel plate as the cathode. was energized for 1 minute to form a coating layer with a letter A having a thickness of 8 μm on the aluminum metal surface. Next, this cap is heated in a heating furnace at a temperature of 100°C for 10 minutes to semi-cure the coating layer.
A silver-colored aluminum metal foil of stamping foil was closely attached on top of the stamping foil, heated to a temperature of 180°C, and pressed with a silicone rubber elastic body to press the aluminum foil. This cap was then heated in a heating oven at a temperature of 150° C. for 20 minutes to strongly adhere the aluminum foil and harden the coating layer.

I was able to decorate the top of the blue cap with a shiny silver letter A with high precision.

In addition, the aluminum foil should be placed at a distance of 2μ from the surface of the cap.
It existed in a concave portion about m low.

Example 2 A CO ₂ gas laser beam was irradiated in Example 1.
Instead of removing the anodized sealing layer marked with the letter A, the anodized sealing layer marked with the letter A was removed by physical cutting using a diamond cutting tool. The other steps were the same as in Example 1, and a cap with almost the same decoration was produced.

Example 3 A brass name plate was treated with acid,
After performing alkaline cleaning treatment, black epoxy paint was applied to the surface of the name plate using an air pressure of 5 kg/cm ^2.
After spray painting in a heating oven at a temperature of 130℃
The coating film was cured by heat treatment for 20 minutes. The thickness of the coating film was 30 μm.

Next, in order to remove the paint film with the letter B on one side of this name plate, the original image scanning to read the original image and the laser beam scanning to reproduce and irradiate the same image on the irradiated surface of the original image are synchronized. conduct
A YAG laser beam (wavelength: 1.06 μm) generator was used. This device captures the original image with a TV camera, converts the image analog data output from the TV camera into on/off values, and controls laser beam irradiation on/off according to the on/off values. It's getting old. In other words, B
At the same time, an image of the letter B is captured and scanned by a television camera on the original image of the letter B on the coating film.
The YAG laser beam was irradiated and scanned to remove the paint film and expose the brass metal surface marked with the letter B. The conditions for irradiating the laser beam are:
Beam diameter: 120 μmφ, output: 12 W, Q switch frequency: 50 KHz, feed speed: 300 mm/sec.

Next, this name plate is immersed in an emulsion bath of epoxy cation type electrodeposition coating resin with a liquid temperature of 20℃ and a non-volatile content of 25 wt%, and the name plate is used as a cathode and the stainless steel plate is used as an anode.
A direct current of 100 V was applied for 2 minutes to form a 28 μm thick coating layer labeled B on the exposed brass metal surface. Next, this name plate is heated in a heating oven at a temperature of 100℃ for 15 minutes to semi-cure the coating layer, and a stamping foil of gold aluminum metal foil is closely attached to it and heated to a temperature of 180℃. Pressure was applied using the silicone rubber elastic body prepared to press the aluminum foil. Next, this name plate was top coated by spray painting with a transparent epoxy resin paint, and heated in a heating oven at a temperature of 130°C for 30 minutes to strongly adhere the aluminum foil and harden the paint layer. I was able to decorate the black name plate with a shiny gold letter B.

Note that the aluminum foil was present on almost the same surface as the name plate surface.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are sectional views of main parts showing the method of the present invention in order. 1... Metal product, 2... Non-conductive film layer, 3...
...metallic surface (portions such as letters, designs, etc.), 4...paint layer, 5...metal foil.

Claims (1)

[Scope of Claims] 1. After forming a non-conductive film layer on the surface of a metal product, a desired portion of the non-conductive film layer is removed according to arbitrary characters, designs, etc. to form a conductive metal surface. is exposed on the surface, and then a thermosetting resin is electrodeposited on the metal surface to form a coating layer whose upper surface is lower than the surface of the non-conductive coating layer, and the coating layer is completely cured. After pressing the metal foil of the stamping foil onto the coating layer with a heated elastic body before curing the coating layer, the metal foil of the stamping foil for curing the coating layer is on the same surface as the surface of the non-conductive coating layer on the metal surface, or A method for decorating metal products characterized by the presence of lower recesses. 2. The method for decorating a metal product according to claim 1, wherein the metal of the metal product is aluminum or an aluminum alloy. 3. The method for decorating metal products according to claim 2, wherein the non-conductive film layer is an anodic sealing film. 4. The method for decorating a metal product according to claim 1, wherein the metal of the metal product is copper or a copper alloy. 5. The method for decorating metal products according to any one of claims 1, 2, and 4, wherein the non-conductive film layer is a non-conductive paint film. 6. The method for decorating metal products according to any one of claims 1 to 5, wherein the method for removing a desired portion of the non-conductive film layer is a physical cutting method. 7. A method for decorating a metal product according to any one of claims 1 to 5, wherein the method for removing a desired portion of the non-conductive film layer is a method of irradiating a laser beam.