JP4499071B2 - Metal extruded tube, its production method and its use - Google Patents

Description

  The present invention provides a resin coating with high reliability that it is dense and has almost no pinholes, is excellent in elongation at break, and does not cause cracks due to deformation such as bending. The present invention relates to a metal extruded tube formed on the inner wall surface, an aerosol can, and a method for producing the metal extruded tube.

  Conventionally, a metal extruded tube that pushes out the viscous contents housed inside by pushing the body part to deform the composition to accommodate various foods, medicines, cosmetics, etc. Has been used.

  The metal extruded tube includes a trunk portion made of a metal wall that is easily plastically deformed, and a shoulder portion and a neck portion that are continuous with one end of the trunk portion. The other end of the body portion of the metal tube is closed by fastening or the like, and the mouth and neck portion is closed freely by a cap.

  In such a metal extruded tube, the outside air or moisture (water vapor) that intrudes little by little over a long period of time from one end or the like, or the metal constituting the body deteriorates the contents, or the contents It is desirable to prevent objects from corroding the metal barrel. Conventionally, as such a metal extruded tube, an approximately complementary resin tube is fitted into the inside of the metal tube whose one end is opened, and the contents are filled from the open end of the resin tube, Next, a so-called double tube type extruded tube, in which an open end is sealed by heat sealing by pressurizing and heating through a metal tube, has already been proposed. However, this double tube type metal extruded tube has various improvements such as many processes, difficult alignment of metal outer cylinder and resin inner cylinder, and adjustment of dimensional tolerance difference. In addition, since it is difficult to avoid an increase in manufacturing cost, it can only be used for extremely limited applications. Moreover, in this type of extruded tube, the resin tube mounted inside tends to restore its original shape due to its thickness and elasticity, so that it is difficult to completely discharge the contents. was there.

  Also, a thermosetting resin coating is sprayed on the inner wall surface of the body, and the obtained coating film is cured by heating to form a thermosetting resin coating, for example, an epoxy-phenol resin coating or a phenol-butyral resin coating. Extrusion tubes have also been proposed. However, it has been almost impossible for thermosetting resin coatings to achieve both prevention of pinholes and prevention of cracks caused by deformation such as bending.

  That is, thermosetting resins are generally hard and tend to crack when subjected to deformation such as bending, but the tendency to crack is more pronounced when the film thickness is 15 μm or more. In addition to this, the thermosetting resin film generates coating defects due to air bubbles mixed in the coating film when it is formed, and pinholes are generated in the resin film obtained by heating and curing this. There was a problem that it was easy. And if it is going to make a thermosetting resin film sufficiently thin in order to prevent generation | occurrence | production of a crack, this pinhole generation | occurrence | production will become further remarkable. The occurrence of pinholes can be alleviated to some extent by recoating the paint film. However, many times of recoating make the paint film formation process complicated, and it is necessary to re-apply as many times as necessary to completely eliminate the pinhole. If it is performed, the total film thickness is at least 20 μm or more. Therefore, it has been difficult to apply a sufficient number of times of coating in order to prevent poor coating within a film thickness range that can reduce the occurrence of cracks.

In other words, it is difficult to prevent the occurrence of pinholes in the resin film in the conventional extruded tube having a thermosetting resin film having a film thickness of 5 to 15 μm, and in order to eliminate pinholes, the film of the resin film If the thickness is 20 μm or more, cracks due to deformation such as bending cannot be prevented, and as a result, the quality of the metal barrel or contents is deteriorated in any case. Therefore, the thermosetting resin film of the conventional extruded tube has room for improvement in the protective function for the metal barrel and contents.

  In a metal extruded tube having a thermosetting resin coating on the inner wall surface of the body, the stage after the thermosetting resin coating is heat-cured and then the contents are received from the open end, that is, the open end (hem) is provided. At the stage of fastening, it is necessary to apply an end seal material such as rubber latex to the inner wall of the open end region in order to maintain airtightness. Therefore, this metal extruded tube has a problem that the fastening process is complicated and the productivity is insufficient.

  Moreover, there exists an aerosol can as a container provided with the trunk | drum which consists of metal walls similarly to a metal extrusion tube. The aerosol can usually has a cylindrical body with a bottom made of a metal wall, and a shoulder and a neck that are continuous to the upper end of the body are provided. An assembly is provided. And the chemical | medical agent and cosmetics which are accommodated in an aerosol can with propellants, such as high pressure gas, will be sprayed outside via this valve assembly by the action | operation of a valve assembly.

  Even in such an aerosol can, it is desirable that the metal constituting the body part does not deteriorate the contents, or the contents do not corrode the metal body part. A resin film made of epoxy-phenolic resin, epoxy-urea resin, vinylorgano resin, fluororesin such as polytetrafluoroethylene and perfluoroethylene, polyamide such as nylon 12, polyester such as polyethylene terephthalate, polyethylene, etc. .

  However, even in such a resin coating, poor coating due to bubbles or the like mixed in the coating during the coating formation occurred, and pinholes were easily generated in the obtained resin coating. The occurrence of pinholes can be alleviated to some extent by overcoating the coating film. However, many times of overcoating make the coating film formation process complicated and there is a problem that productivity is lacking.

  The present invention has been made in order to solve the problems associated with the prior art described above, and is dense, almost free of pinholes, excellent in elongation at break, and caused by deformation such as bending. Providing a metal extrusion tube with a high degree of reliability that does not cause cracks and the like, and a metal coating on the inner wall surface, and a method for producing the same, with an excellent protection function for the metal barrel and contents The purpose is to do.

  In addition, the present invention provides an aerosol can in which a resin film having a dense and almost no pinhole and having an excellent protection function for a metal barrel and contents is formed on the inner wall surface from another viewpoint. The purpose is that.

  It is another object of the present invention to provide an apparatus that enables the method for producing a metal extruded tube according to the present invention.

The metal extruded tube of the present invention is easily deformed plastically and is closed at one end, a shoulder portion and a neck portion that are continuous with the other end of the barrel portion, and an inner wall surface of the barrel portion. A metal adhesive heat formed by spray-coating a spherical fine particle dispersion made of a metal-adhesive thermoplastic resin on the undercoat layer made of a thermosetting resin layer, and then heating and fusing the particles. And a resin film made of an overcoat layer made of a plastic resin layer.

  The method for producing a metal extruded tube according to the present invention includes a metal barrel part that is easily plastically deformed and that is open at one end, and a shoulder part and a mouth-and-neck part that are continuous with the other end of the trunk part. A step of forming an undercoat layer made of a thermosetting resin layer on the inner wall surface of the extruded tube before storing an object, and spray coating a spherical fine particle dispersion made of a metal-adhesive thermoplastic resin on the undercoat layer to obtain a uniform thickness A step of forming a coating film, and a step of heating the coating film and heating and fusing the resin spherical fine particles to form an overcoat layer made of a metal-adhesive thermoplastic resin. .

  The metal aerosol can of the present invention includes a bottomed cylindrical body, a shoulder and a mouth and neck that are continuous with the other end of the body, a valve assembly provided on the mouth and neck, and an inner wall surface of the body A metal adhesive formed by spray-coating a spherical fine particle dispersion made of a metal-adhesive thermoplastic resin on the undercoat layer made of a thermosetting resin layer, and then heating and fusing the particles. And a resin film having a top and bottom coating layer made of a heat-resistant thermoplastic resin layer.

  The coating apparatus according to the present invention is an apparatus that makes it possible to produce the above-described metal extruded tube, and is movable along the long axis direction of the metal cylindrical body in which at least one of the objects to be coated is opened, A coating unit provided with a nozzle having a paint spray port at the tip for spraying paint on the cylindrical body wall surface, and the spray port centered between the paint spray port of the coating unit and the cylindrical body wall surface And a drive unit that generates a relative motion in a substantially circumferential direction.

  According to the metal extruded tube of the present invention and the manufacturing method thereof, the spherical fine particle dispersion made of a metal-adhesive thermoplastic resin is spray-coated on the undercoat layer made of a thermosetting resin formed on the inner wall surface of the body part, Next, due to the contribution of forming a resin film having a metal-adhesive thermoplastic resin layer formed by heating and fusing the particles, it is dense and almost free of pinholes, and has an excellent elongation at break. It is made of metal with a high degree of reliability that prevents cracks caused by deformation such as bending, and has a resin coating on the inner wall surface that provides excellent protection for metal barrels and contents. An extruded tube can be provided.

  Further, according to the metal aerosol can and the manufacturing method thereof according to the present invention, the spherical fine particle dispersion made of the metal-adhesive thermoplastic resin is sprayed on the undercoat layer made of the thermosetting resin formed on the inner wall surface of the body portion. Coating, and then contributing to the formation of a resin film having a metal-adhesive thermoplastic resin layer formed by heating and fusing the particles, which is dense and almost free of pinholes, It is possible to provide an aerosol can in which a resin film having an excellent protective function against contents is formed on the inner wall surface thereof.

  The metal extruded tube according to the present invention has a metal main body constituting the outer shell portion of the tube, and a topcoat layer made of a metal-adhesive thermoplastic resin layer formed by a specific method on the inner wall surface of the body portion of the main body. And a resin coating. Here, a preferred embodiment of the metal extruded tube of the present invention will be described with reference to the accompanying drawings.

In the present specification, the term “layer” constituting the resin film includes one formed by one coating and one formed by repeated coating of the same resin, and includes two adjacent “
“Layer” means formed from different resins. However, the adjacent layers may not have a clear interface with each other, and are not necessarily firmly bonded.

  FIG. 1 (A) is a schematic cutaway longitudinal sectional view of an extruded tube showing a reference example of the present invention, and FIG. 2 (B) is a schematic partially enlarged view showing a resin coating layer structure of the extruded tube of the present invention. . As shown in the figure, this extruded tube 1 is composed of a metal body 3, a metal main body 2 composed of a shoulder 5 and a mouth-and-neck part 7 continuous with the other end of the body 3, and a body 3. It is a container provided with a resin coating 9 formed on the inner wall surface and containing a highly viscous liquid or viscous material.

  A male screw is provided on the outer periphery of the neck portion 7, and this male screw is detachably engaged with a female screw in the cap 15 of the extruded tube 1. Such a metal main body 2 of the extruded tube 1 is made of a wall thickness and a material whose body 3 can be plastically deformed. Examples of the material of the body portion 3 include a thin plate or a foil obtained by extending a metal selected from aluminum, an aluminum alloy, tin, a tin alloy, lead, and the like. In this embodiment, the shoulder portion 5 and the mouth and neck portion 7 that are continuous with one end of the trunk portion 3 are formed of the same material as that of the trunk portion 3, but in the present invention, the material of the shoulder portion 5 and the mouth and neck portion 7 is particularly limited. Not limited.

  Among such materials for the body 3, aluminum and its alloys are preferred for many applications, and aluminum metal is particularly preferred. However, for various reasons, other metals, such as lead, may be suitably used. For example, among the above metals, lead is soft, can withstand repeated bending, and can be easily perforated with a thin pointed object such as a sewing needle, and the tube contents can be extracted from the hole by squeezing or extruding. Therefore, when not storing for a long time in an environment where lead is corroded, it may be preferable to manufacture the main body 2 with lead.

  In the extruded tube 1 of the present invention, the resin coating 9 formed on the inner side of the metal barrel 3 has a thermosetting resin layer 51 (undercoat layer) in contact with the barrel 3 as shown in FIG. And a metal-adhesive thermoplastic resin 53 (overcoat layer) on the thermosetting resin layer.

  Examples of the adhesive thermoplastic resin used for forming the metal adhesive thermoplastic resin layer 53 constituting the resin coating 9 include metal adhesive polyolefin, for example: polyolefin backbone polymer, dicarboxylic acid, unsaturated carboxylic acid, etc. Dicarboxylic acid graft-modified polyolefin and unsaturated carboxylic acid graft-modified polyolefin obtained by grafting graft monomers; 1-olefin / unsaturated carboxylic acid copolymer obtained by copolymerization of 1-olefin and unsaturated carboxylic acid And the above-mentioned unsaturated carboxylic acid graft-modified polyolefin and alkali metal salts and alkaline earth metal salts (ionomers) of the 1-olefin / unsaturated carboxylic acid copolymer.

  The trunk polymer used to produce the dicarboxylic acid graft-modified polyolefin and unsaturated carboxylic acid graft-modified polyolefin may be either a crystalline homopolymer or a crystalline crystalline copolymer.

  Moreover, as a monomer used for preparation of this trunk polymer, C1-C6 1-olefin, specifically, ethylene, propylene, 1-butene, 4-methyl-1-pentene, etc. can be illustrated, these are It may be used alone or in combination of two or more. Among these 1-olefins, ethylene and propylene can be exemplified as particularly preferable monomers, but a backbone polymer using 4-methyl-1-pentene may be suitable for applications where heat resistance is important.

The trunk polymer may be an amorphous copolymer (elastomer). Examples of such an amorphous copolymer include ethylene-propylene amorphous copolymer, ethylene / 1-butene. Examples thereof include an amorphous copolymer and an ethylene-4-methyl-1-pentene amorphous copolymer.

  Monomers used for preparing such dicarboxylic acid graft-modified polyolefin or unsaturated carboxylic acid graft-modified polyolefin by modifying such a backbone polymer include aliphatic dicarboxylic acids such as maleic acid and norbornene dicarboxylic acid, and the like. Examples thereof include unsaturated dicarboxylic acids such as acid anhydrides and tetrahydrophthalic acid and acid anhydrides thereof, unsaturated monocarboxylic acids such as (meth) acrylic acid, and the like. These may be used alone or in combination of two or more. The dicarboxylic acid graft-modified polyolefin using these monomers is most preferably maleic anhydride graft-modified polyolefin, particularly maleic anhydride graft-modified low-density polyethylene.

  The 1-olefin / unsaturated carboxylic acid copolymer can be prepared using the 1-olefin having 1 to 6 carbon atoms and the di- and mono-unsaturated carboxylic acid described above. 1-olefin can be used by appropriately selecting one or more kinds from the specific examples described above.

  Examples of the ionomer include the unsaturated carboxylic acid graft-modified polyolefin or 1-olefin / unsaturated carboxylic acid copolymer described above, for example, methacrylic acid graft-modified polyethylene or ethylene / methacrylic acid copolymer sodium salt, Examples include potassium salts, calcium salts, and zinc salts.

  In the ionomer used in the present invention, two or more kinds of metal cations may be contained in the same polymer. Moreover, although a metal ion can be suitably selected according to the use of an ionomer, generally sodium ion and potassium ion are preferable.

  The above-described adhesive polyolefins may be used alone or in combination of two or more, and the adhesive polyolefin is not modified in such an amount that the adhesiveness is not substantially reduced. It can also be used as an adhesive polyolefin composition to which polyolefin is added.

  Among such adhesive polyolefins, ionomers and adhesive low density polyethylene, particularly maleic anhydride graft modified low density polyethylene, are particularly excellent in adhesion to metal.

  In the resin coating 9 having such a layer structure, in particular, the metal-adhesive thermoplastic resin layer 53 is spray-coated with spherical fine particle dispersion made of a metal-adhesive thermoplastic resin, and then the particles are heated and fused. It is formed.

  The spherical fine particles of the metal-adhesive thermoplastic resin preferably have a uniform particle size and high sphericity. FIG. 7 is a photomicrograph of spherical fine particles having a uniform particle diameter formed of an adhesive thermoplastic resin suitable for forming a metal-adhesive thermoplastic resin layer, each of which has a spherical shape or a long and narrow spherical shape (ellipsoidal shape). And its particle size is highly uniform. That is, there are very few particles with extremely small diameters among the particles displayed in FIG. Moreover, no sharp or bent portions such as ridges or vertices are found at all.

The dispersion used in the present invention is obtained by stably dispersing such spherical fine particles in a dispersion medium such as water. Such spherical fine particle dispersions are already commercially available, and among them, a suitable one, for example, an aqueous dispersion of ionomer resin spherical fine particles commercially available from Mitsui Petrochemical Co., Ltd. under the trade name “Chemical”. It is sufficient to appropriately select (aqueous dispersion) or the like according to the purpose.

  Here, the preferable manufacturing method of the extrusion tube including the resin film 9 formation process using such a spherical fine particle dispersion is demonstrated with reference to drawings. FIG. 3 is a conceptual structural diagram of an apparatus for applying the dispersion to the inner wall surface of the extruded tube. In FIG. 3, reference numeral 1a denotes an aluminum tube to be processed, which is connected to the other end of the body 3 with one end opened. The shoulder 5 and the mouth and neck 7 are continuously formed.

  The aluminum tube 1a is housed inside the tubular holder 31 and is supported on the inner side of the holder 31. The aluminum tube 1a is supported at the predetermined speed by a drive mechanism (not shown) with the long axis X as a central axis. It is rotated. Inside the aluminum tube 1a, a rod-shaped spray gun nozzle 33 which is disposed substantially parallel to the axis X and can be moved back and forth along the axis X by a drive mechanism (not shown) is inserted. The spray gun nozzle 33 is provided with a conduit (not shown) for feeding the dispersion, and a tip 37 of the tip 35 is oblique to the major axis X (intersection angle (θ) 25 to 60 degrees). Are formed, and a plurality of injection holes 39 are provided in this plane.

  In the dispersion coating using such an apparatus, the nozzle 33 moves along the long axis of the aluminum tube while spraying the dispersion supplied from the resin fine particle dispersion storage tank (not shown) from the ejection hole 39. . The dispersion ejected from the ejection holes 39 is regulated by the intersection angle of the flat surface 37 and ejected radially in an oblique direction (intersection angle (θ) 25 to 60 degrees) with respect to the axis X. Further, as the nozzle moves, the aluminum tube 1 rotates around the axis X while being held by the holder 31, and as a result, on the undercoat layer made of a thermosetting resin on the inner wall surface of the aluminum tube 1a. A resin fine particle dispersion made of a metal adhesive thermoplastic resin is uniformly applied.

  The resin fine particle dispersion coating film formed in this way is a dense resin layer, that is, a metal-adhesive thermoplastic, by volatilizing the dispersion medium and then heating and melting the remaining resin fine particles to a predetermined temperature. The resin layer 53 can be formed.

  The thickness of the metal-adhesive thermoplastic resin layer 53 is determined by changing the fine particle concentration of the resin fine particle dispersion, repeating the resin fine particle dispersion coating film forming step, repeating the steps until the dispersion medium volatilizes, or the resin. It can select suitably by the overcoat by the repetition of the process to fine particle heat fusion. Therefore, for example, the thick metal-adhesive thermoplastic resin layer 53 can be prepared by multiple recoating or particularly using a high-concentration dispersion.

  As an excellent point of the thermoplastic resin, it is possible to form a thick resin film with less cracking than the thermosetting resin film. According to the spray coating apparatus of the present invention, the upper limit of the thickness of the metal-adhesive thermoplastic resin layer can usually be increased to about 250 μm. For example, if supercritical carbon dioxide or the like is used as a dispersion medium, the productivity is increased. It is possible to achieve a film thickness far exceeding 250 μm by significantly speeding up the volatilization of the medium while maintaining the thickness. In addition, if graft modified polyolefin whose trunk polymer is an elastomer is used as the metal-adhesive thermoplastic resin, there is an advantage that cracks and the like are not particularly likely to occur when the metal-adhesive thermoplastic resin layer is thickened.

  In the resin film 9 formed in this way, the entire film thickness and the layer thickness of each layer are not particularly limited, but the metal-adhesive thermoplastic resin layer 53 as an overcoat layer is usually usually an average layer thickness of 5 to 150 μm, The thickness is preferably 5 to 50 m, and the overall film thickness is 10 μm or more, preferably 10 to 250 μm.

  Such a resin film 9 is a dense film composed of a protective layer having an average pinhole degree (thickness of 30 μm) of 50 mA or less, an elongation at break of 200% or more, and a crack occurrence rate of 0 by a crusher test.

  Here, the “dense” coating means the pinhole degree (thickness 30 μm standard), that is, the pinhole presence rate per area is 50 mA or less, preferably 3 mA measured by the measurement method described later (current value), more preferably Means 20 mA or less. Furthermore, since this pinhole degree (thickness of 30 μm standard) is inversely related to the thickness of the film (layer thickness), the pinhole degree of the present invention (thickness of 30 μm standard) has an average layer thickness of 30 μm. It is a numerical value when

Further, such a resin film 9 can have a crack generation rate of 0 by a crusher test. Here, “crack rate 0” means a level that is industrially feasible (
(Statistical level) means "0". Although the expression rate is extremely low, it is not “0” in the mathematical (logical) sense.

  The aluminum tube 1a on which the resin coating 9 described above is formed has caps 15 attached to the shoulder portion 5 and the mouth-and-neck portion 7, and is filled with contents from the open end. Then, the open end is folded, and the resin coating 9 (thermoplastic resin layer) is heat-sealed as necessary to form the extruded tube 1.

  FIG. 1C is a schematic cross-sectional view showing another embodiment of a resin coating in a metal extruded tube according to a reference example of the present invention. This resin coating 9 is made of two metal adhesive layers, that is, made of aluminum. A metal-adhesive thermoplastic resin layer 41 made of adhesive low-density polyethylene formed on the surface of the body 3 and a metal-adhesive made of ionomer resin formed on the surface of the metal-adhesive thermoplastic resin layer 41. And a thermoplastic resin 43. In the resin film 9 of this embodiment having such a layer structure, at least one of the metal-adhesive thermoplastic resin layers 41 and 43 is formed by the above method using a resin fine particle dispersion.

  FIG. 2 (B) is a diagram showing an embodiment of a metal extruded tube according to the present invention. As shown in the figure, the extruded tube 1 of this embodiment has the same structure as that of the reference example, and the same reference numerals are given to the same parts. In particular, as shown in FIG. 2B, the resin coating 9 formed on the inner wall surface of the barrel portion 3 of the extruded tube 1 includes a thermosetting resin layer 51 as an undercoat layer and the thermosetting resin. It consists of a metal-adhesive thermoplastic resin layer 53 as an overcoat layer formed on the surface of the layer 51.

  The thermosetting resin used for forming the thermosetting resin layer 51 constituting the resin coating 9 may be any thermosetting resin conventionally used for manufacturing the metal extruded tube 1, For example, an epoxy resin and a phenol resin can be used. More specific examples of such thermosetting resins include epoxy / phenolic resins and phenol / butyral resins.

  The thermosetting resin layer 51 (undercoat layer or primer coat) made of such a thermosetting resin may be formed by any conventionally known method, for example, a solution or a disperser containing an uncured thermosetting resin. The paint which is John can be spray-coated on an aluminum tube to form a coating film, which is then heated and cured.

Further, when forming the coating film, it is desirable to apply the coating in at least two times until the coating film reaches a predetermined thickness. Usually, these applications are repeated with a drying process between each operation. That is, for example, after completion of the first coating operation, it is usual to perform a treatment (intermediate drying) that volatilizes and removes the solvent or dispersion medium in the paint (coating agent). In addition, volatilization removal may not be required if it is a coating which consists of a liquid prepolymer and does not produce the gas or the liquid by-product accompanying hardening.

  By repeatedly applying in this way, it is possible to effectively prevent the coating film from dripping [commonly called “sag”; sag (Sag)] and preventing pinholes. That is, when the predetermined layer thickness is about 17 to 18 μm, if this layer thickness is set to one layer up to this layer thickness, the coating drips, the coating film is deformed, and the predetermined thickness is partially applied. Often, coating thickness is not achieved. Such sagging is effectively prevented by multiple applications with a drying step in between.

  In addition, the pinhole residual probability of the coating film is the maximum when the coating film is a single layer, and the coating finally obtained by applying the coating film a number of times (overcoating) before reaching the predetermined film thickness. The incidence of pinholes formed in the film can be reduced. However, in the coating with a thermosetting resin, that is, when the overall film thickness is about 15 μm or more, cracks are likely to occur in the thermosetting resin layer.

  After such a coating film forming operation, the coating film is cured (baked). When an epoxy-based paint is used, it is sufficient that this curing operation is usually performed at a temperature of about 250 ° C. (curing temperature) for 5 to 10 minutes. Further, when a phenolic paint is used, the curing operation is usually performed at a temperature of about 180 ° C. for about the same time. In addition, intermediate drying in the case of repeatedly applying at the time of forming the coating film is not baking, and it is sufficient to carry out at a temperature of about 100 ° C. for 3 to 5 minutes.

  In this embodiment, the metal adhesive thermoplastic resin layer 53 is formed on the surface of the thermosetting resin layer 51 formed in this way. Also in the resin film 9 of this embodiment having such a layer structure, the metal-adhesive thermoplastic resin 53 is formed by the above method using resin fine particle dispersion.

  It is desirable that the resin coating 9 thus obtained also has the same film thickness, overcoat layer thickness, and undercoat layer thickness as in the reference example, and the pinhole degree and crusher test characteristics similar to those in the above-described embodiment. Can be expected.

  In addition, after the resin coating 9 is formed, the cap 15 is attached, the contents are filled from the open end, the open end is then fastened, and the resin coating 9 (thermoplastic resin layer is formed) as necessary. ) Can be heat sealed to form an extruded tube 1.

  In addition, in the metal extruded tube of this aspect, the thermosetting resin layer 51 as the undercoat layer and the metal adhesive thermoplastic resin layer 53 as the overcoat layer are made of materials that hardly generate an adhesive force to each other. Can be formed.

As described above, the resin film in which the thermosetting resin layer 51 and the metal-bonded thermoplastic resin layer 53 are formed of materials having no mutual adhesive force have the following advantages.
1) When folded, a relatively small force is sufficient. The reason is that both layers do not function as a single thick layer due to the separation between the overcoat layer and the undercoat layer;
2) Even when it is bent, cracking of the coating film hardly occurs. The cause is that an adhesive thermoplastic resin that is easy to extend is located on the innermost side (overcoat film);
3) This configuration looks similar to the double tube mentioned in the prior art, but can be manufactured much more productively;
4) When heat sealing is performed at the time of end folding, the metal adhesive thermoplastic resin is fused, but the thermosetting resin layer is not bonded. Therefore, when the contents such as the medicine and cosmetics contained in the cylinder contain a substance that is permeable to the metal adhesive thermoplastic resin layer, such as alcohol, the metal adhesive thermoplastic resin layer is removed. The permeated and gaseous substance can first stay between the two layers and then be released to the outside from the folded end.

  Next, a metal aerosol can according to the present invention includes a metal can body, a resin film having a metal-adhesive thermoplastic resin layer formed on a body inner wall surface of the body by a specific method, and a can body And a valve assembly attached to the mouth and neck. Here, a preferred embodiment of the metal aerosol can of the present invention will be described with reference to the accompanying drawings.

  FIG. 4 (A) is a schematic incision longitudinal sectional view showing a preferred embodiment of the metal aerosol can according to the present invention, and FIG. 4 (B) is a schematic part showing the resin coating layer structure of the aerosol can of the reference example. FIG. 5 is an enlarged cross-sectional view of an upper portion of an aerosol can equipped with a valve assembly. As shown in the figure, this aerosol can 61 includes a metal can main body 62 and a valve assembly 69, and propels the solution, suspension, etc. accommodated in the interior, and the high-pressure gas, etc. accommodated in the interior. A container for spraying through the valve assembly 69 with the pressure of the agent.

  The can body 62 of the aerosol can 61 has a bottomed cylindrical metal barrel 63, a shoulder 65 and a neck portion 67 that are continuous with the tip of the barrel, and an inner wall surface of the barrel 63. A resin coating 9 is formed on the mouth and neck portion 67, and a valve assembly 69 is attached.

  The valve assembly 69 has a known configuration, and includes a valve housing 81, a spring 82 that is accommodated in the valve housing 81 and biases the valve body 89 upward, a stem rubber 83 that closes the valve housing, and the stem A stem 84 that penetrates the rubber 83 and has a lower end abutting against the valve body 89 is provided. The valve housing 81 has a dip tube 88 attached to the lower end thereof, and is inserted into the mouth and neck portion 67 with a packing 85 attached to the outer periphery thereof. In such a state, the valve assembly 81 accommodates the valve housing 81 and the stem rubber 83 and caulks the lower end of the cap-shaped metal cover 89 whose bottom portion penetrates the stem 84 from the outside of the mouth-and-neck portion 6. Thus, the mouth and neck part 67 is fixed. A spray head 90 is attached to the upper end of the stem 84.

  In the metal body 62 of such an aerosol can, the body portion 63, the shoulder portion 65, and the mouth and neck portion 67 are integrally formed of a metal plate such as an aluminum plate, an aluminum alloy plate, and a tin-plated steel plate.

  Here, the preferable manufacturing method of the aerosol can including the formation process of the resin film 9 using such spherical fine particles will be described with reference to the drawings. FIG. 6 is a conceptual structural diagram of an apparatus for applying the dispersion to the inner wall surface of the can body. In FIG. 6, reference numeral 62 denotes a can main body to be painted, and the same parts as those in FIG.

  The can body 62 is held by a rotatable holding jig (not shown), and is rotated at a predetermined speed by a drive mechanism (not shown) with the long axis X as a central axis. A rod-shaped spray gun nozzle 74 that is disposed substantially parallel to the axis X and can be moved back and forth along the axis X by a drive mechanism (not shown) is inserted into the can main body 62. The spray gun nozzle 74 is provided with a pipeline (not shown) for feeding the dispersion, and the tip 75 thereof is a plane portion that is oblique to the major axis X (intersection angle (θ) 25 to 60 degrees). 76 is formed, and an injection hole 77 is provided in the flat portion.

In the dispersion application using such an apparatus, the nozzle 74 is directed upward along the long axis of the aluminum tube while spraying the dispersion supplied from the resin fine particle dispersion storage tank (not shown) from the ejection port 77. Moving. The dispersion ejected from the ejection holes 77 is restricted by the intersection angle of the plane 76 and is ejected radially in an oblique direction (intersection angle (θ) 25 to 60 degrees) with respect to the axis X. In addition, as the nozzle moves, the can body 62 rotates about the axis X by the rotation of the holding jig. As a result, the dispersion of resin fine particles made of a metal-adhesive thermoplastic resin on the inner wall surface of the can body 62 Will be applied uniformly.

  The resin fine particle dispersion coating film formed in this way is then subjected to volatilization of the dispersion medium, followed by heating and melting and bonding the remaining resin fine particles to a predetermined temperature, that is, a metal adhesive property. A thermoplastic resin layer 71 can be formed.

  In the resin film 9 thus formed, the total film thickness and the layer thickness of each layer are not particularly limited, but the metal adhesive thermoplastic resin layer 71 as the undercoat layer is usually an average layer thickness of 5 to 100 μm, preferably Is 5 to 20 μm, the thermoplastic resin layer 73 as the overcoat layer is usually an average layer thickness of 5 to 150 μm, preferably 5 to 100 μm, and the overall film thickness is set to 10 μm or more, preferably 10 to 250 μm. preferable.

  Such a resin film 9 is a dense film reaching an average pinhole degree (thickness of 30 μm standard) of 50 mA or less. The can main body 62 formed with the resin coating 9 described above has the valve assembly 69 fixed to the mouth-and-neck portion 67 as described above, and liquid chemicals or cosmetics to be the contents, high-pressure gas (liquefied gas), etc. The propellant is injected into an aerosol can 61.

  FIG. 4D is a schematic cross-sectional view showing an embodiment of the resin coating in the metal aerosol can according to the present invention, and this resin coating 9 is thermosetting formed on the inner wall surface of the body 63 of the can body 62. It consists of a resin layer 96 and a metal-adhesive thermoplastic resin layer 97 formed on the surface of the thermosetting resin layer 96.

  As the thermosetting resin used for forming the thermosetting resin layer 96 constituting the resin coating 9, for example, an epoxy resin and a phenol resin can be used. More specific examples of such thermosetting resins include epoxy / phenolic resins and phenol / butyral resins.

  The thermosetting resin layer 96 made of such a thermosetting resin may be formed by any conventionally known method. For example, the third embodiment of the layer structure in the resin coating 9 of the metal extruded tube 1 will be described. It is possible to form by this method.

  In this embodiment, the metal-adhesive thermoplastic resin layer 97 formed on the surface of the thermosetting resin layer 96 thus formed is formed by the above method using resin fine particle dispersion.

The resin film 95 thus obtained also has the same film thickness, overcoat layer thickness, and undercoat layer thickness as in the reference example, and can be expected to have the same pinhole degree as in the above-described embodiment.
In the metal aerosol can 1 having such an aspect, when a liquid that easily corrodes the thermosetting resin, for example, an emulsion in which a strongly acidic aqueous solution is dispersed in an organic dispersion medium, is introduced into the can, the liquid is aged over time. Since the thermoplastic resin layer 96 can be protected by the metal-bonded thermoplastic resin layer 97 made of ionomer or the like, the reliability of the resin coating can be further increased.

  The resin film 9 thus obtained preferably has the same film thickness, overcoat layer thickness, and undercoat layer thickness as in the above-described embodiment, and has the same pinhole degree as in the above-described embodiment. You can expect.

  The can body 62 having the resin coating 9 of the embodiment shown in FIG. 4D described above also has the valve assembly 69 mounted and fixed to the mouth-and-neck portion 67 as described above, and the liquid chemical or makeup as the contents A propellant such as a fuel and high-pressure gas (liquefied gas) is injected into the aerosol can 61.

The following methods and criteria were used to measure and evaluate the effects of the present invention:
(1) Resin film thickness: 25 μm;
[Measuring device] Strand gauge [Product name: Strand gauge (manufactured by Strand Gauge Electronics)]
[Measurement operation] A sample piece was mounted between the measurement terminals of the apparatus, the measured electrical conductivity was converted into an electric characteristic current, and the resin film thickness was measured with the displayed value:
[Sample Piece] Length 150 mm × Width 75 mm × Thickness 0.11 mm;
[Conditions for adjustment] temperature 27 ° C. × humidity 65% RH × 1 h;
[Measurement conditions] Temperature 25 ° C. × Humidity 60% RH × Time 2 h; Number of measurements 6 times;
(2) Pinhole degree (thickness 30μm standard) After covering the sample metal tube (with inner wall coated) with a cap and filling the inside with a highly conductive aqueous solution, the outer surface of this metal tube An electrode was attached to the electrode and the electrode was immersed in an aqueous solution, and the current value to conduct was measured:
[Measurement condition]
Applied voltage: DC6V;
Aqueous solution: 5% NaCl + 1% CuSO ₄ + 0.05% CH ₃ COOH mixed solution.
(3) Resin Film Strength (Interlayer Adhesive Strength) Cross Cut Test The flat surface of the resin coat is cut and 11 vertical lines and 11 horizontal lines are cut at 1 mm intervals with a cutter to create a 1 mm × 1 mm grid. After sticking the adhesive tape on the grids of the 100 sections, the number and distribution of peeled portions (peeled sections) generated when the adhesive tape is abruptly peeled off are measured.

Crusher test A tube with a coating film is compressed in the longitudinal direction and then stretched, and the coating film is measured for cracks, cracks and peeling.
Abrasion test After flattening the surface of the resin film, the surface of the resin film is rubbed with gauze impregnated with a solvent such as toluene to observe the state of the film.

[Reference Example 1]
A high-purity aluminum tube (1) with standard shoulder and neck and neck shapes is used as the metal tube, and the tube is inserted into the holder (31) so that the neck and neck side faces the back. The shoulder was brought into contact with the starting end of the reduced diameter region and fixed. Next, a rod-shaped spray gun nozzle (33) was inserted in parallel with the long axis of the aluminum tube toward the inside thereof. The tip of the spray gun has a flat surface portion (37) having an intersecting angle of about 45 degrees with respect to the long axis, and in this flat surface portion, an injection hole (injecting paint in a direction substantially perpendicular to the surface) 39).

While rotating the holder (31) around its long axis (1750 rpm), adhesion of spherical uniform particle diameter from the tip of the spray gun nozzle (33) to the inner wall surface of the aluminum tube (1) at a direction of about 45 degrees. Ionomer-based resin (density: 0.948 g / cm ³ ; tensile strength: 355 kgf / cm ² ; elongation at break: 360%; Vicat softening point: 60 ° C.) as a conductive polyethylene 28% by weight concentration; pH 10 of aqueous dispersion medium; viscosity 320 cP; average particle size of solids 0.1 μm or less; minimum film forming temperature 89 ° C .;
1.25 g / sec). At this time, the spray gun nozzle (33) is connected to the aluminum tube (1).
It moved to the exit side (linear velocity 270-340 mm / sec).

An aluminum tube (1) coated with the dispersion once on the inner wall surface is heated at 120 to 150 ° C. 3
A dense undercoat resin layer (21: average film thickness of 15 μm) was formed by heating for ˜5 minutes.
A non-modified low-density polyethylene [MI (190 ° C .; 2.16 kgf) 25 g / 10 min; density 0.915 g / cm ³ ] as the second coating is overcoated on the surface by the same operation as above to form a comprehensive film Then, the aluminum tube (1) was transferred into the welding furnace with a scissor accommodated in the holder (31). Heat in a welding furnace at a welding temperature of 150 to 155 ° C. for 3 to 5 minutes, melt the low-density polyethylene fine particle layer by coating, and fuse it well with the undercoat layer (21) to form an overcoat layer (average film thickness 17 μm). Obtained.

  On the topcoat layer, an unmodified low-density polyethylene fine particle aqueous dispersion is applied twice in the same manner as described above, and the dispersion medium is volatilized and removed at a temperature of 150 ° C. and heat-sealed. The top coat layer (23) was finished to obtain a resin film having a total film thickness of 66 μm.

As a result of performing various measurements on the obtained tube (1) of the present invention according to the procedure and conditions shown in the above-mentioned “Measurement and Evaluation of Effects” column, the following results were obtained:
(1) Film thickness: 66 μm;
(2) Pinhole degree: 10 mA (66 μm);
(3) Film strength (interlayer adhesion): 1.25 kgf / 15 mm;
(4) Cross cut test: Pass;
(5) Crusher test: Pass;
(6) Wear test: Passed.

[Reference Example 2]
Using the same aluminum tube (1) and the same coating apparatus as in Reference Example 1, a rod-shaped spray gun nozzle (33) is parallel to the long axis (X) of the aluminum tube (1) and directed inward. Inserted.

Adhesive low-density polyethylene as an undercoat paint supplied from a storage tank (not shown) while rotating (1750 rpm) around the long axis of a holder (31) containing an aluminum tube (1) by a drive device (not shown) [Dispersion 0.92 g / cm ³ ; tensile strength: 83 kgf / cm ² ; elongation at break: 330%; Vicat softening point: 78 ° C.] %; PH of aqueous dispersion medium: 9; viscosity: 5000 cP; average particle size: 5 μm; minimum film forming temperature: 106 ° C.] from the tip of spray gun nozzle (33) to the inner wall surface of aluminum tube (1). The spray gun nozzle (33) is moved to the outlet side of the aluminum tube (1) (linear velocity of 270 to 340 mm / min) by spraying in the direction of 45 degrees (0.65 to 1.62 g / min) and by a driving means (not shown). sec).

The aluminum tube (1) with the dispersion applied once on the inner wall surface is heated at 150 ° C. for 2 minutes to volatilize the dispersion medium, and then gradually raised to a temperature of 195 ° C. at 5 ° C./min to reduce the solid content. A dense undercoat layer (41: average film thickness: 22 μm) was completed while being melted.

  On this undercoat layer, an adhesive high-density polyethylene aqueous dispersion having the following properties was applied twice using the same apparatus as described above, and each was heated at a temperature of 120 to 150 ° C. for 3 to 5 minutes to obtain an overcoat layer (43: (Average film thickness: 30 μm) was completed to obtain a resin film having a total film thickness of 52 μm.

Adhesive low density polyethylene aqueous dispersion: solid content concentration 27 wt%; pH 10 of aqueous dispersion; viscosity 300 cP; average particle size 0.1 μm or less; true density of raw resin 0.946 g / cm ³ ; tensile strength 35083 kgf / cm ² ; elongation at break 360%; Vicat softening point 60 ° C.

As a result of performing various measurements on the obtained tube of the present invention in accordance with the procedure and conditions shown in the “Measurement and Evaluation of Effect” column, the following results were obtained:
(1) Film thickness: 52 μm;
(2) Pinhole degree: 17 mA (52 μm);
(3) Film strength (interlayer adhesion): 1.26 kgf / 15 mm;
(4) Cross cut test: Pass;
(5) Crusher test: Pass;
(6) Wear test: Passed.

[Reference Example 3]
Using the same aluminum tube (1) and the same coating apparatus as in Reference Example 1, a rod-shaped spray gun nozzle (33) is parallel to the long axis (X) of the aluminum tube (1) and directed inward. Inserted.

Adhesive polyethylene of spherical uniform particle size supplied from a storage tank (not shown) while rotating a holder (2) containing an aluminum tube (1) around its major axis (1750 rpm) by a driving device (not shown). As an ionomer-based resin (density: 0.948 g / cm ³ ; tensile strength: 355 kgf / cm ² ; elongation at break: 360%; Vicat softening point: 60 ° C.) : 28 wt%; pH of aqueous dispersion medium 10; viscosity 320c
P; average particle size of solid content: 0.1 μm or less; minimum film forming temperature: 89 ° C .; at an angle of about 45 degrees with respect to the inner wall surface of the aluminum tube (1) (0.5 to 1. 25 g / min), and the spray gun nozzle (33) was moved to the outlet side of the aluminum tube (1) (linear velocity: 270 to 340 mm / sec).

  The aluminum tube (1) on which the dispersion was applied once on the inner wall surface was heated at a temperature of 120 to 150 ° C. for 3 to 5 minutes to form a dense undercoat layer (average layer thickness 15 μm). The same uniform particle size spherical fine particle aqueous dispersion liquid as the first coating is applied to the surface by the same operation, the second coating is applied, and then the aluminum tube (1) is boiled in the holder (31). Was transferred into the welding furnace. The coating was heated in a welding furnace at a welding temperature of 120 to 150 ° C. for 3 to 5 minutes to melt the ionomer fine particle layer by coating and fully fuse it with the undercoat layer to obtain a resin film having a total film thickness of 30 μm.

The obtained extruded tube (1) was subjected to various measurements according to the procedures and conditions shown in the “Measurement and Evaluation of Effect” column, and the following results were obtained:
(1) Film thickness: 30 μm;
(2) Pinhole degree (thickness 30 μm standard): 47 mA;
(3) Film strength (interlayer adhesion): 1.05 kgf / 15 mm;
(4) Cross cut test: Pass;
(5) Crusher test: Pass;
(6) Wear test: Passed.

[Example 1]
Using the same aluminum tube (1) and the same coating apparatus as in Reference Example 1, a rod-shaped spray gun nozzle (33) is parallel to the long axis (X) of the aluminum tube (1) and directed inward. Inserted.

While rotating the holder (31) around its long axis (1750 rpm), the epoxy / phenol-based paint [45 [deg.] From the tip of the spray gun nozzle (33) to the inner wall of the aluminum tube (1) [ Epoxy component content 23% by weight; phenol component content 1
0% by weight; trade name AON302T-100 (manufactured by Tanaka Chemical Co., Ltd.)] (0.4 to 1.0)
5 g / min) and the spray gun nozzle (31) was moved to the outlet side of the aluminum tube (1) (linear velocity: 270 to 340 mm / sec).

An aluminum tube (1) coated with paint once on the inner wall is 0.3 at a temperature of 90-110 ° C.
After intermediate drying for ˜1.0 minutes, the resulting undercoat layer having a film thickness of about 7 μm was coated to the total film thickness of about 15 μm by the same operation as described above using the above-mentioned epoxy / phenol-based paint. Next, the aluminum tube (1) was transferred into the baking furnace with the scissors accommodated in the holder (31). Heating was carried out in a baking oven at a baking temperature of 210 to 270 ° C. for 4 to 7 minutes to sufficiently cure the epoxy / phenolic thermosetting resin coating, thereby obtaining an undercoat layer (51) having an average film thickness of 15 μm.

On this undercoat layer (51), an ionomer aqueous dispersion having the following properties is applied twice using the same apparatus as described above, and heated at a temperature of 120 to 150 ° C. for 3 to 5 minutes, respectively, and then coated with an adhesive polyolefin. A layer (53: overall film thickness 30 μm) was obtained. The sum of the thickness of the thermosetting resin layer (51) and the thickness of the adhesive polyolefin resin layer (53) reached 45 μm.

Ionomer aqueous dispersion: solid content concentration 27% by weight; aqueous dispersion pH 10; viscosity 320 cP; average particle size 0.1 μm or less; true density of raw resin 0.95 g / cm ³ ; tensile strength 350 kgf / cm ² ; Elongation 350%; Vicat softening point 58 ° C.

The productivity of this double layer extruded tube reached about twice that of the conventional extruded tube. The obtained extruded tube (1) was subjected to various measurements according to the procedures and conditions shown in the “Measurement and Evaluation of Effect” column, and the following results were obtained:
(1) Film thickness: Undercoat film: 15 μm; Topcoat film: 30 μm;
(2) Pinhole degree: 22 mA (45 μm);
(3) Film strength (interlayer adhesion): 0 kgf / 15 mm;
(4) Cross cut test: almost all areas peeled (almost no adhesion was observed between the undercoat layer (U3) and the overcoat layer (T));
(5) Crusher test (interlayer adhesion test between undercoat layer and metal surface): Pass;
(6) Abrasion test (interlayer adhesion test between undercoat layer and metal surface): Passed.

[Reference Example 4]
A high-purity aluminum plate can body (62) having the shape shown in FIG. 6 and having a body (63) diameter of 25 mm and a wall thickness of 0.4 mm is held upright (not shown) ). Next, a rod-shaped spray gun nozzle (74) was inserted inwardly in parallel with the long axis of the can body. The tip of the spray gun nozzle has a flat portion (76) fixed at an angle of about 45 degrees with respect to the long axis, and the flat portion (76) is provided with a paint injection port (77). It has been.

Then, while rotating the can main body (62) with a rotating jig (1750 rpm), an ionomer system as an adhesive polyethylene having a spherical uniform particle diameter from the tip of the spray gun nozzle (74) to the inner wall surface of the can main body in a direction of approximately 45 degrees. Resin (density: 0.948 g / cm ³ ; tensile strength: 355 kg
f / cm ² ; Elongation at break: 360%; Vicat softening point: 60 ° C. uniform particle size spherical fine particle aqueous dispersion (solid content concentration 28% by weight; dispersion medium pH 10; viscosity 320 cP; solid content average particle) The diameter was 0.1 μm or less; the minimum film forming temperature was 89 ° C .;) was sprayed (0.9 to 1.6 g / sec), and the pregun nozzle (74) was moved upward (linear velocity: 270 to 340 mm / sec) .

The can body (62) having the dispersion applied once on the inner wall surface was heated at a temperature of 120 to 150 ° C. for 3 to 5 minutes to form a dense undercoat resin layer (71: average film thickness of 15 μm). Subsequently, in order to form an overcoat layer, unmodified low density polyethylene [MI (190 ° C .; 2.16 kgf)] is formed on the surface.
25 g / 10 min; density 0.915 g / cm ³ ] The fine particles were applied by the same operation as above, and the can body (62) was transferred into the welding furnace. Heat in the welding furnace at a welding temperature of 150-155 ° C. for 3-5 minutes,
The low-density polyethylene fine particle layer by coating was melted and sufficiently fused with the undercoat film (71) to obtain an overcoat layer (73; average film thickness of 15 μm).

  On the top coat layer (73), non-modified low density polyethylene fine particles are applied twice in the same manner as described above, and heat-sealed at a temperature of 150 ° C. to finish the top coat layer and complete the coating film. A resin film having a thickness of 50 μm was obtained.

As a result of performing various measurements on the obtained aerosol cans according to the procedure and conditions shown in the “Measurement and Evaluation of Effects” column, the following results were obtained:
(1) Film thickness: 50 μm;
(2) Pinhole degree: 14 mA (50 μm);
(3) Film strength (interlayer adhesion): 1.23 kgf / 15 mm;
(4) Cross cut test: Pass;
(5) Wear test: Passed.

FIG. 1A is a schematic longitudinal sectional view showing a preferred embodiment of a metal extruded tube according to a reference example of the present invention, and FIG. 1B is a partially enlarged sectional view showing a layer structure of the resin film. FIG. 1C is a partially enlarged cross-sectional view showing another preferred embodiment of the layer structure in the resin coating. FIG. 2A is a schematic cross-sectional view showing an embodiment of the tube of the present invention, and FIG. 2B is a partially enlarged cross-sectional view showing a layer structure in the resin film. FIG. 3 is a schematic cross-sectional view for explaining a method of coating an extruded tube according to the present invention. FIG. 4A is a schematic longitudinal sectional view showing a preferred embodiment of a metal aerosol can according to a reference example of the present invention, and FIG. 4B is a partially enlarged sectional view showing a layer structure in a resin film of the reference example. FIG. 4C is a partial enlarged cross-sectional view showing a layer structure in the resin film of the reference example, and FIG. 4D is a partial enlarged cross-sectional view showing an aspect of the layer structure in the resin film according to the present invention. is there. FIG. 5 is a partially enlarged sectional view showing the structure of the valve assembly of the aerosol can according to this embodiment. FIG. 6 is a schematic cross-sectional view for explaining an aerosol can coating method according to the present invention. FIG. 7 is a photomicrograph of a group of spherical fine particles having a uniform particle size suitable for forming the metal adhesive thermoplastic resin layer of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Extrusion tube 2 Main body 3 Trunk part 5 Shoulder part 7 Neck part 15 Cap 31 Holder 33 Spray gun nozzle 39 Ejection hole 21, 41, 43, 53, 71, 78, 79, 97 Metal-adhesive thermoplastic resin layers 23, 73 Thermoplastic resin layers 51, 96 Thermosetting resin layer

Claims (3)

A metal barrel portion that is easily plastically deformed and closed at one end, a shoulder portion and a mouth-and-neck portion continuous to the other end of the barrel portion, and an undercoat layer made of a thermosetting resin layer on the inner wall surface of the barrel portion And a resin coating comprising an overcoat layer comprising an ionomer layer formed by spray-coating a spherical fine particle dispersion comprising an ionomer on the undercoat layer and then heating and fusing the particles. Metal extruded tube. On the inner wall surface of the barrel of the extruded tube before containing contents, comprising a metal barrel that is easily plastically deformed and has a shoulder and a mouth and neck that are continuous with the other end of the barrel, A step of forming an undercoat layer made of a thermosetting resin layer, a step of forming a coating film having a uniform thickness by spraying a spherical fine particle dispersion made of an ionomer on the undercoat layer after curing the undercoat layer , and the coating film was heated and manufacturing method of the metal tube, characterized in that it comprises a step of forming an overcoat layer made of the resin spherical particles by heating and fusing ionomers made from the ionomer. A cylindrical body with a bottom, a shoulder and a mouth / neck part continuous to the other end of the body part, a valve assembly provided at the mouth / neck part, and a thermosetting resin layer on the inner wall surface of the body part the subbing layer and the subbing layer, the spherical fine particles dispersion comprising an ionomer spray coating, then be provided with a resin coating, a having a topcoat Ri layer made of ionomer layer formed by a heated and fused particles A metal aerosol can characterized by