JP2006096381A - Metal container production method and metal container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal container production method for protecting a dispersion type coating material which is an internal face coating material. <P>SOLUTION: In the metal container production method, the dispersion type coating material in which powder particles are dispersed and suspended in a solvent is applied to the internal face of the metal container, and a thermosetting resin is applied to the layer of coating material. A white coating layer or size coating layer is printed on the external face of the metal container. Subsequently, print ink layer including a pattern, color, and the like is formed. Then thus formed layers are dried and cured in a drying furnace at a temperature of 200 to 270°C. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal container, and more specifically, after the inner surface of a metal container such as a metal tube container is printed, the inner surface coating is damaged even when the outer surface is printed and dried at a high temperature in a drying furnace. The present invention relates to a method for manufacturing a metal container and a metal container.

Conventional metal containers such as metal tube containers and aerosol containers for storing hair dyes, drugs, adhesives, etc., have a holding pin inserted into the metal container after the inner surface coating, and the metal container is placed on the outer surface. It is conveyed to the printing process. That is, the inner surface of a metal container such as a metal tube container or an aerosol container, such as epoxy phenol resin, epoxy amino resin, vinyl resin, or the like, is used to prevent direct contact between the contents and the metal container. A dispersion-type paint in which a resin paint is applied and powder particles are dispersed and suspended in a solvent is applied thereon (Patent Document 1). In such a conventional metal container, the outer surface coating, which is a printing process, is usually provided with a white coat layer and a size coat layer such as polyester as a base coat layer, on which acrylic, epoxy, polyester, polyurethane A desired pattern or the like is printed with ink of a system or the like. And after printing, as shown in FIG. 8, it is supported by the support pin 52 attached to the chain conveyor 51, is conveyed in a drying furnace, and is a base coat layer (for about 15 to 20 minutes at a temperature of about 200 to 270 ° C. Alternatively, the size coat layer) and the printing ink layer on the outer surface were dried and cured (Patent Document 2).

Japanese Patent Laid-Open No. 10-157750 Japanese Patent Laid-Open No. 10-15632

However, as shown in FIG. 8, a conventional metal container such as a metal tube container or an aerosol container is formed on the inner surface of the metal layer 53 of the metal container 50 with a vinyl resin such as vinyl organosol or a thermoplastic resin such as nylon. Or, a polyolefin-based, polyester-based, nylon-based, etc. in which a thermosetting resin paint such as epoxy resin such as epoxy phenol or epoxy melamine or acrylic resin is coated and powder particles are dispersed and suspended in a solvent. In the subsequent printing process, when baked at a temperature of about 200 to 270 ° C. for 15 to 20 minutes, the chain conveyor 51 and the support pins are applied. The surface temperature of No. 52 also rises to 200 to 270 ° C., and the dispersion type paint which is the innermost layer softens and melts. . When the support pin is in direct contact with the softened and melted dispersion-type paint, the inner surface coating film is damaged, so that the contents permeate from the damaged portion and the metal container corrodes. Therefore, some measure for protecting the dispersion type paint has been required.

The reason why the dispersion-type paint is applied to the innermost surface that comes into contact with the contents is that it can fill the pinholes generated in the coating film, and is excellent for the protection of metal layers of metal containers such as aluminum and resistance to contents It is because it has the effect. However, since the heat resistant temperature of the dispersion type paint is 150 to 200 ° C., there is a problem that the dispersion type paint is softened and melted in a high temperature drying furnace for drying a conventional printing ink layer. is there. The present invention has been made paying attention to such a conventional problem. Even when the outer surface is printed and dried at a high temperature in a drying furnace after the inner surface coating step, the dispersion-type paint is applied. It aims at providing the manufacturing method of a metal container, and the metal container which improved the corrosion resistance of the metal container by the content by preventing a film | membrane being damaged.

The solution of the invention described in claim 1 is to apply a dispersion-type paint in which powder particles are dispersed and suspended in a solvent on the inner surface of a metal container, and then apply a thermosetting resin thereon to protect it. A method for producing a metal container, comprising printing a white coat layer or a size coat layer on an outer surface, then forming a printing ink layer such as a pattern and color, and drying and curing at 200 to 270 ° C. in a drying furnace. It is. In order to apply a thermosetting resin on the dispersion type paint, when it is dried in a drying oven at 200 to 270 ° C., the dispersion type paint softens and melts. Since the dispersion-type paint is protected because it is painted, even if the support pin attached to the chain conveyor is inserted into the metal container, the dispersion-type paint that is slightly molten in the drying process The coating film can be prevented from being directly damaged by the support pins. Moreover, the formation of the thermosetting resin coating can prevent the content from penetrating into the dispersion type coating film and the metal container surface.

According to a second aspect of the present invention, there is provided a metal container manufacturing method characterized in that a topcoat layer is formed on a printing ink layer. Thereby, the printing ink layer can be protected.

According to a third aspect of the present invention, there is provided a metal container manufacturing method, wherein the dispersion-type paint is an acid-modified polyolefin-dispersed paint. The acid-modified polyolefin-dispersed paint has better heat resistance than other paints such as acid-modified polyester and acid-modified nylon.

The solution of the invention according to claim 4 is to apply a dispersion-type paint in which powder particles are dispersed and suspended in a solvent to the inner surface of the metal container, and then apply a thermosetting resin thereon to protect it. A metal container characterized in that a white coat or size coat layer is formed on the outer surface, and a printing ink layer such as a pattern or color is formed thereon.

According to a fifth aspect of the present invention, there is provided a dispersion type paint in which powder particles are dispersed and suspended in a solvent, and a thermosetting resin is coated on the inner surface of the metal container. A metal container characterized in that a white coat or size coat layer, a printing ink layer such as a pattern and color, and a top coat layer are further formed thereon.

According to a sixth aspect of the present invention, there is provided a metal container characterized in that the metal container is a metal tube container. When the metal container is a metal tube container, the top coat layer is usually not painted.

The solution of the invention described in claim 7 is characterized in that the metal container is a threaded metal container. When the metal container is a threaded metal container, the topcoat layer is usually painted.

The solution of the invention according to claim 8 is a metal container, wherein the metal container is an aerosol container. When the metal container is an aerosol container, the top coat layer is usually painted.

According to this invention, even when the outer surface is printed and then dried at a high temperature in a drying furnace, the slightly melted dispersion type paint can be prevented from being directly damaged, The penetration by the contents can be prevented, and the corrosion resistance of the metal container can be improved.

In the outer surface printing and drying process, when drying at a high temperature, the inner surface coating film of the dispersion type paint is in a slightly melted state to prevent direct damage and to prevent the penetration of the contents. This was realized by forming a protective coating film of a thermosetting resin on the dispersion type paint.

FIG. 1 is a metal tube container showing Example 1 of the present invention, and FIG. 2 shows an enlarged cross-sectional view of part A of the metal tube container 1. The metal tube container 1 is made of a metal such as aluminum, and a dispersion type paint 3 in which powder particles such as polyethylene or polypropylene are dispersed and suspended in a solvent is applied to the inner surface of a metal layer 2 such as aluminum. As the dispersion type paint, for example, an acid-modified polyolefin dispersion paint 3 is applied. Polypropylene resin having good heat resistance is suitable for the polyolefin resin powder particles, and the mixing ratio is preferably 10 to 30% by weight, preferably 20% by weight, based on the mixed paint. The solvent is preferably toluene from the viewpoint of drying property, and the mixing ratio is preferably 50 to 80% by weight, preferably 65% by weight, based on the mixed paint. The thickness of the dispersion type paint 3 is 10 to 25 μm, the thickness of the thermosetting resin 4 is 10 to 25 μm, and the thickness of the entire coating film is 20 to 50 μm, preferably 15 to 25 μm. As other solvents, solvesso, methyl ethyl ketone, alkaline water, or the like can be used, and polyethylene or the like can be used as powder particles of other polyolefin resins. It goes without saying that a dispersion type paint such as polyester or nylon can be arbitrarily selected depending on the contents filled in the metal container.

  A feature of the present invention resides in that an epoxy resin such as epoxy phenol or epoxy melamine, or a thermosetting resin paint such as a fluorine resin or an acrylic resin is applied on the acid-modified polyolefin dispersion paint 3. The inner surface coating film becomes more reliable and stable, and even if it is affected by heat, it is protected by these thermosetting resin paints. Although it is conceivable to apply a thermoplastic resin such as vinyl organosol after the dispersion type paint is applied, the thermoplastic resin is similarly softened and melted in a high-temperature drying furnace. It is not suitable as a protective coating for John-type paints. The outer surface printing performed thereafter is printing of a pattern or the like printed by a conventionally known printing process. On the metal layer 2, as a normal base coat layer, a white coat layer such as polyester or a size coat layer 5 is applied, and thereafter, by a printing ink layer 6 such as acrylic, epoxy, polyester, polyurethane, etc. A desired pattern or the like is printed.

After the dispersion type paint 3 is applied to the inner surface of the metal container 2, the drying temperature is 150 to 200 ° C., which is the melting temperature of the dispersion type paint 3, and is 1 to 10 minutes at 150 to 230 ° C. Suitable. In addition, after the thermosetting resin paint 4 to be applied is applied on the dispersion type paint 3, the drying temperature is a temperature at which the internal dispersion type paint 3 is not affected, 150 to 230 °. 3-15 minutes at C is suitable. Thereby, the dispersion type paint 3 can completely fill the pinhole generated in the coating film, and has an excellent effect on the protection and content resistance of the metal layer such as aluminum, and the thermosetting paint. The dispersion type paint 3 is protected by 4. As another example, a thermosetting resin paint 4 such as epoxy phenol or epoxy melamine, which is applied on the acid-modified polyolefin dispersion paint 3, is applied once and then dried, and further a thermosetting resin paint 4 is obtained. It may be painted. By applying the thermosetting resin coating 4 multiple times, the coating film of insufficient thermosetting resin (coating defects such as bubbles and paint pools) is corrected later, and the inner surface coating is completed It can be. In addition, when the content 8 is a strong alkali or strong acid content such as a hair dye, a metal tube in which the thermosetting resin 4 is coated on the dispersion type coating 3 of the inner surface coating film according to the present invention. By using a metal tube container (not shown) in which a synthetic resin inner cylinder is inserted in the container 1, corrosion of the container can be further prevented by these synergistic effects.

FIG. 3 shows a threaded metal container 11 according to the second embodiment of the present invention, and FIG. 4 shows an enlarged cross-sectional view of part B of the threaded metal container 11. The threaded metal container 11 is formed of a metal such as aluminum, and a dispersion-type paint 13 in which powder particles such as polyethylene or polypropylene are dispersed and suspended in a solvent is coated on the inner surface of a metal layer 12 such as aluminum. . As the dispersion type paint, for example, an acid-modified polyolefin dispersion paint is applied. The polyolefin resin powder particles are preferably polypropylene having good heat resistance, and the mixing ratio is preferably 10 to 30% by weight, preferably 20% by weight, based on the mixed paint. The solvent is preferably toluene from the viewpoint of drying property, and the mixing ratio is preferably 50 to 80% by weight, preferably 65% by weight, based on the mixed paint. The thickness of the dispersion type paint 13 is 10 to 25 μm, the thickness of the thermosetting resin 14 is 10 to 25 μm, and the thickness of the entire coating film is preferably 20 to 50 μm, and preferably 15 to 25 μm. As other solvents, solvesso, methyl ethyl ketone, alkaline water, or the like can be used, and polyethylene or the like can be used as powder particles of other polyolefin resins. It goes without saying that other dispersion-type paints can be arbitrarily selected.

A feature of the present invention resides in that an epoxy resin such as epoxy phenol or epoxy melamine, or a thermosetting resin paint 14 such as a fluorine resin or an acrylic resin is applied on the acid-modified polyolefin dispersion paint 13. The inner surface coating film becomes more reliable and stable, and is protected by the thermosetting resin coating 14 even if it is affected by heat. Although it is conceivable to apply a thermoplastic resin such as vinyl organosol after the dispersion type paint 13 is applied, the thermoplastic resin is similarly softened and melted in a high-temperature drying furnace. It is not suitable as a protective coating for John-type paints. Next, the outer surface printing is printing of a pattern or the like printed in a conventionally known printing process. That is, a polyester-based white coat layer or a size coat layer is applied on the metal layer 12 as a normal base coat layer 15, and then an acrylic, epoxy-based, polyester-based, polyurethane-based printing ink layer 16. Thus, a desired pattern or the like is printed. Further, an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, and a vinyl resin are provided as a top coat layer 17 and a transparent resin on the printing ink layer. Is protected. The drying temperature condition and the conveying method are the same as in Example 1. A threaded metal container (not shown) in which an inner cylinder of a synthetic resin is inserted into a threaded metal container 11 in which a thermosetting resin 14 is coated on a dispersion type paint 13 having an inner surface coating film according to the present invention. By using, the corrosion of the container can be further prevented.

FIG. 5 shows an aerosol container 21 showing Example 3 according to the present invention. FIG. 6 is an enlarged sectional view of C and D parts of the aerosol container 21. FIG. 5A shows an aerosol container 21 having a normal curled portion, and FIG. 5B shows a small aerosol container 21. These aerosol containers 21 are formed of a metal such as aluminum, and a dispersion-type paint 23 in which powder particles such as polyethylene or polypropylene are dispersed and suspended in a solvent is applied to the inner surface of a metal layer 22 such as aluminum. Yes. As the dispersion type paint 23, for example, an acid-modified polyolefin dispersion paint is applied. The polyolefin resin powder particles are preferably polypropylene having good heat resistance, and the mixing ratio is preferably 10 to 30% by weight, preferably 20% by weight, based on the mixed paint. The solvent is preferably toluene from the viewpoint of drying property, and the mixing ratio is preferably 50 to 80% by weight, preferably 65% by weight, based on the mixed paint. The polyolefin resin powder particles are preferably polypropylene having good heat resistance, and the mixing ratio is preferably 10 to 30% by weight, preferably 20% by weight, based on the mixed paint. The solvent is preferably toluene from the viewpoint of drying property, and the mixing ratio is preferably 50 to 80% by weight, preferably 65% by weight, based on the mixed paint. The thickness of the dispersion-type paint 23 is 10 to 25 μm, the thickness of the thermosetting resin 24 is 10 to 25 μm, and the thickness of the entire coating film is preferably 20 to 50 μm, and preferably 15 to 25 μm. As other solvents, solvesso, methyl ethyl ketone, alkaline water, or the like can be used, and polyethylene or the like can be used as powder particles of other polyolefin resins. It goes without saying that other dispersion-type paints can be arbitrarily selected. It goes without saying that a dispersion type paint such as polyester or nylon can be arbitrarily selected depending on the contents filled in the metal container.

A feature of the present invention resides in that an epoxy resin such as epoxy phenol and epoxy melamine, and a thermosetting resin paint 24 such as a fluorine resin and an acrylic resin are applied on the acid-modified polyolefin dispersion paint 23. The inner surface coating film becomes more reliable and stable, and even if it is affected by heat, it is protected by this thermosetting resin paint. Next, the outer surface printing is printing of a pattern or the like printed in a conventionally known printing process. That is, a polyester-based white coat layer or a size coat layer 25 is applied on the metal layer 22 as a normal base coat layer, and then an acrylic-based, epoxy-based, polyester-based, polyurethane-based printing ink layer 26 or the like. Thus, a desired pattern or the like is printed. Further, an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, and a vinyl resin are provided on the printing ink layer as the top coat layer 27 as a transparent resin. Protected. The drying temperature condition and the conveying method are the same as in Example 1. In addition, an aerosol container (not shown) in which an inner cylinder of a synthetic resin is inserted into an aerosol container 21 in which a thermosetting resin 24 is coated on a dispersion type paint 23 having an inner surface coating film according to the present invention is used. Thus, corrosion of the container can be further prevented.

In the aluminum tube container in which the outer surface according to the present invention is normally printed, the dispersion type paint in which the powder particles are dispersed and suspended in the solvent is coated on the inner surface, and the epoxy melamine resin is coated thereon, the hair dye 2 A storage test was conducted after filling with the agent, and compared with a conventional aluminum tube container.
(Test conditions)

-Contents: Two hair dyes containing hydrogen peroxide.

Storage period: It was carried out in two modes of 3 months at 40 ° C. and 6 months at 40 ° C.

・ Test sample;
(1) Sample A (aluminum tube container according to the present invention): a coating of a dispersion resin of a polypropylene resin on an aluminum surface and a coating of an epoxy melamine resin thereon (number of samples N = 5).

(2) Sample B (conventional aluminum tube container): an epoxy phenolic resin coated on the aluminum surface and the contents filled into an inner cylinder of polyethylene resin (number of samples N = 3).

◎；異常なし ○；塗膜軽度異常

△；塗膜異常（アルミ表面腐食なし）

▲；アルミ表面腐食

×；アルミ表面下地穴明き


（試験結果）

４０℃で３ヶ月経過及び４０℃で６ヶ月経過後に、目視観察を行った結果、上記表１から明らかなように、従来の試料（Ｂ）では、アルミ表面が腐食するサンプルがあったが、本発明に係る試料（Ａ）では、アルミ表面が腐食するサンプルはなかった。これは、熱硬化性の樹脂塗料である、エポキシメラミン樹脂塗料が、ディスパージョン型塗料の保護膜となり、アルミチューブ容器表面への内容物の影響が減少したとめである。

◎: No abnormality ○: Mild abnormality of coating film

△: Abnormal coating film (no aluminum surface corrosion)

▲; Aluminum surface corrosion

×: Aluminum surface base hole drilling


(Test results)

As a result of visual observation after the elapse of 3 months at 40 ° C. and the elapse of 6 months at 40 ° C., as apparent from Table 1 above, in the conventional sample (B), there was a sample in which the aluminum surface was corroded. In the sample (A) according to the present invention, no sample corroded the aluminum surface. This is because epoxy melamine resin paint, which is a thermosetting resin paint, becomes a protective film for the dispersion type paint, and the influence of the contents on the surface of the aluminum tube container is reduced.

As an application example of the present invention, it can be used as an inner surface coating of a metal tube container, an aerosol container or the like for storing a hair dye, a drug, an adhesive or the like. And a hair dye container, a permanent agent container, a medicine storage container, a food container, a soft drink container, an alcoholic beverage container, etc. can be filled widely.

The partially cutaway sectional view showing the metal tube container of Example 1 of the present invention. The expanded sectional view which shows the A section of FIG. The partially cutaway sectional view showing a threaded metal container of Example 2 of the present invention. The expanded sectional view which shows the B section of FIG. The partially cutaway sectional view showing an aerosol container of Example 3 of the present invention. The expanded sectional view which shows the C section and D section of Fig.5 (a) (b). Conventionally, the front view which shows the conveyance chain which shows the state which conveys a metal tube container in a drying furnace. The expanded sectional view which shows the X section of FIG.

Explanation of symbols

1 Metal tube container 2 12 22 Metal layer 3 13 23 Dispersion type paint 4 14 24 Thermosetting resin 5 15 25 White coat layer or size coat layer 6 16 26 Printing ink layer 8 18 28 Contents 17 27 Top coat layer 11 Threaded metal container 21 Aerosol container

Claims (8)

  A dispersion-type paint in which powder particles are dispersed and suspended in a solvent is applied to the inner surface of a metal container, and a thermosetting resin is applied to protect it, and a white coat layer or size coat layer is printed on the outer surface. Then, a printing ink layer having a pattern, color or the like is formed, and dried and cured at 200 to 270 ° C. in a drying furnace. The method for producing a metal container according to claim 1, wherein a topcoat layer is formed on the printing ink layer.
The method for producing a metal container according to claim 1 or 2, wherein the dispersion type paint is an acid-modified polyolefin dispersion paint.
A dispersion-type paint in which powder particles are dispersed and suspended in a solvent is applied to the inner surface of the metal container, and a thermosetting resin is applied to the coating, and a white coat layer or size coat layer is applied to the outer surface. A metal container characterized by forming a printing ink layer such as a pattern or color on the surface.
A dispersion-type paint in which powder particles are dispersed and suspended in a solvent is applied to the inner surface of the metal container, and a thermosetting resin is applied to protect it, and a white coat layer or size coat layer is applied to the outer surface. Metal container characterized by forming a printing ink layer such as a pattern and color on the top and a top coat layer
The metal container according to claim 4, wherein the metal container is a metal tube container.
6. The metal container according to claim 5, wherein the metal container is a threaded metal container.
The metal container according to claim 5, wherein the metal container is an aerosol container.

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