WO2011018493A1

WO2011018493A1 - Method for producing metal packages

Info

Publication number: WO2011018493A1
Application number: PCT/EP2010/061732
Authority: WO
Inventors: Rainer Klenk
Original assignee: Huber Packaging Group Gmbh
Priority date: 2009-08-12
Filing date: 2010-08-12
Publication date: 2011-02-17
Also published as: US20120201630A1; EP2464573B1; EP2464573A1; DE102009038129A1

Abstract

The invention relates to a method for producing metal packages having the steps of forming a metal package (10), particularly of steel or aluminum, from a sheet metal material, particularly of thin or very thin or tin sheet, having an interior (12), and coating the interior (12) with a coating agent (30) based on paraffin. The coating agent (30) is preferably heated to a temperature above the solidification temperature after coating (Fig. 5).

Description

Process for the production of metal packaging

The invention relates to a method for producing metal packaging from sheets with a coating and metal packaging of sheet material, in particular of sheet or Feinst- or tinplate, for receiving a filling in an interior.

Such metal packages are basically known in the art and are described by the Applicant et al. in the form of flat cans, canisters, Falzverschlussdosen, hobbocks or barrels distributed.

Such metal packaging comes in the packaging and storage of chemical / technical products, food and especially drinks for use. They are prepared by methods generally known in the art involving separation and forming processes. In this connection, connections are produced, inter alia, by folding operations, wherein previously flanged edges of sheets are connected to each other by crimping.

With the help of the known metal packaging, it is possible to protect the above-mentioned contents protected from light and tight in a mechanically stable container. The tightness extends here to liquid, vaporous and gas-tight components of the contents, as well as an undesirable permeation is avoided by the packaging material. In addition, such containers are suitable to receive pressurized products. Metal packaging is almost completely recyclable, which, if consistently recovered and recycled, can result in a nearly closed material cycle for the packaging materials.

To ensure the corrosion, acid and general media resistance of the containers, it is necessary to provide their surfaces, especially the insides, with a protective coating. This coating can e.g. a combination of a metallic layer, for example a tinned tinplate, and an organic coating applied thereto, e.g. a paint job or a foil application. Such coatings are generally applied to the semifinished product, the flat material, sheet material or the metal strip prior to forming.

It has been found that the forming processes of the starting material following the production of the metal packaging, such as drawing, flanging or folding operations, may impair the protective effect, in particular of a lacquer layer. For this reason, as an alternative or in addition, the interior of a completed or semi-finished metal packaging has been coated with paints in the ejection process. It should be noted, however, that the varnish layer is not applied to all packaging components by means of the injection molding process. can be, for example, in packaging interiors with hard to reach areas or with very small filling openings.

As part of the subsequent application of paints, it is necessary to follow the coating a drying process. Here, the varnish layer becomes at a significantly elevated temperature, say at 180 to 200 ° C, which remains for a considerable period, e.g. about 12 minutes, applied, dried or baked. This high thermal load necessarily leads to increased equipment costs as well as high energy supply and disposal costs, e.g. Outgassing and evaporation. Furthermore, in such a treatment, the risk of damage to a coating, printing or painting the outside of the packaging be justified.

Against this background, the invention has for its object to provide a method for producing metal packaging with improved corrosion protection and reduced manufacturing costs. Furthermore, a metal packaging with increased corrosion protection and improved manufacturability should be specified.

This object is achieved in a method for producing metal packaging with the following steps:

Forms of a metal packaging, in particular of steel or aluminum, of a sheet material, in particular of fine or very fine or tinplate, with an interior and

Coating the interior with a paraffin-based coating agent.

With regard to a metal packaging according to the aforementioned type, the object of the invention is achieved in that at least the interior has a surface coating with a coating agent based on paraffin. The object of the invention is completely solved in this way.

Namely, according to the present invention, a metal package is formed, and thereafter its inside is coated with a paraffin-based coating agent to give an organic coating which ensures excellent corrosion protection and is not subject to any subsequent mechanical deformation or damage by forming processes in the production of the metal package. In this way, a high integrity of the coating can be ensured.

A particular advantage of the solution according to the invention is also that a significantly reduced porosity is achieved in comparison to (spray) -coated coatings. Consequently, corrosion currents can in principle be minimized or prevented, which leads to a significantly improved corrosion protection. Accordingly, if appropriate, even more aggressive products, such as those which contain acid or lye, can be successfully filled in a packaging according to the invention.

Paraffinic hydrocarbons are non-toxic and are safe in health terms, so they may well be suitable for use in food and beverage packaging. In addition, due to their inertness, paraffins are outstandingly suitable as corrosion inhibitors; in particular, they are not water-soluble and very resistant to many types of acids. Thus, they are particularly suitable for use with carbonated beverage metal packaging, such as e.g. Beer or coke, suitable.

For the purposes of this application, the paraffin-based coating composition is to be understood as a substantially paraffin-containing coating composition which is advantageously more than 75%, preferably more than 85% and more preferably more than 95% paraffin. The coating composition may be supplemented by addition of fillers, solvents, dyes, binders and other additives, such as fats and natural or synthetic waxes, or by additions of production-related residual components, such as oil residues. It is conceivable that the coating agent consists completely or almost completely of paraffin. In this way it can be ensured that no or only insignificant constituents of the coating agent outgas or fire after coating.

In this context, it should be noted that paraffins are to be understood as meaning essentially paraffinic hydrocarbons, which generally have a low tendency to react. Paraffins can be composed of unbranched (n-) and branched (iso) -alkanes, in which their advantageous properties can be justified. Paraffinic hydrocarbons are essentially waxy, odorless and tasteless, electrically non-conductive and hydrophobic.

Depending on their chain structure, paraffins can be classified in terms of their viscosity and their solidification temperature. In the context of this application should be primarily, but not exclusively, be turned off to mixtures with particularly long-chain hydrocarbons. Furthermore, paraffins should also be understood as the so-called microwaxes.

According to one embodiment of the invention, the coating composition is applied under pressure, in particular by airless spraying.

In this way it is possible to apply the coating agent by known techniques. This results in a uniform initial coating. The airless spraying method is particularly suitable for applying the coating composition since, in contrast to air-pressure-based spraying, the coating agent is applied without an additional carrier medium. Thus, contamination of the metal packaging or the coating agent with constituents of the process air can be avoided in a method with compressed air. Likewise unnecessary is an elaborate provision, cleaning or filtering of the process air. In an alternative embodiment of the invention, the coating agent is applied by means of a casting or pouring method.

By this measure, the coating agent can be applied without pressure. Consequently, the manufacturing or equipment costs are reduced. Here, too, can be dispensed with the application of process air for applying the coating agent, so that can reduce contamination of the metal packaging or the coating agent, thereby increasing the manufacturing quality and process reliability.

The application of the coating agent by gravity by means of casting or pouring method can also ensure an influence on the layer thickness to be achieved. By varying various parameters, e.g. Viscosity of the coating composition, temperature of the coating composition or the metal packaging to be coated or the surface texture of the interior of the metal packaging, a desired layer thickness can be adjusted.

In an advantageous embodiment of the invention, the coating composition is heated to a temperature above the solidification temperature for coating.

By this measure, it is possible to process coating compositions based on paraffin without the addition of solvents. In this way, only local areas of the manufacturing plant must be heated, thus a rapid adhesion and solidification of the coating agent is promoted on the not heated by the system metal packaging. It is conceivable to heat the coating agent directly in a storage or storage container or to realize the heat input into the coating agent indirectly via heating of parts of the coating device. In a preferred development of the invention, the coating agent, a solidification temperature of above 70 ° C _1, preferably from about 85 ° C, more preferably from about 90 ⁰ C.

Such high solidification temperatures can be advantageously achieved with micro-axes. In this way, a sufficiently high thermal stability of the applied coating for further processing, filling with the contents and the subsequent use can be ensured.

Furthermore, the solidification temperatures are still low enough to minimize the energy required to heat the coating composition, thus limiting the cost of manufacturing and manufacturing equipment. Furthermore, a protection of the outer surface of the metal packaging is guaranteed against high thermal inputs. Thus, a coating, printing or coating applied externally to the container can be applied to the flat semi-finished product before the sheet metal forming, without prejudice thereto.

It is particularly preferred, after coating, to heat the coating composition again to a temperature above the solidification temperature.

In this way, the applied, already partially or completely solidified coating agent can be melted or melted to completely wet the interior of the metal container with the re-liquefied or viscous paraffin. In addition, inaccessible areas in which no initial application of the coating agent could take place can be wetted. In addition, the integrity or homogeneity of the coating composition or the surface of the coating composition may improve, since the liquid or viscous coating composition is capable of filling microcracks on its surface or gaps in the order or to cure. For this purpose, the applied coating composition is preferably brought to a temperature of about 100 ° C. and kept at this temperature for about two to three minutes. This can result in a significant simplification of the production process and an improvement in the corrosion protection, since possible defects and cracks in the initial layer can be reliably closed or cured by a downstream production step.

In an advantageous embodiment of the invention, at least one seam connection is formed during the molding of the metal packaging, which is coated during the subsequent coating of the interior with the coating agent.

In this way, it has been possible to apply particularly simple, inexpensive and series-suitable forming and joining processes to form the metal packaging, as can be ensured by the coating with a paraffin-based coating agent, particularly hard to reach areas such. Falzkanäle to cover with the coating agent.

In an advantageous embodiment of the invention, the metal packaging for application or reheating of the coating agent for complete wetting of the interior is arranged aligned with the coating agent.

Thus, the liquid or viscous coating agent applied with proper orientation can automatically penetrate under gravity into hard to reach areas of the metal packaging, such as rabbet joints, to ensure a complete coating of the interior. It is conceivable to align the metal packaging several times during production, so that the process reliability of the coating process can increase even further, as well as particularly hard to reach areas can be wetted with the coating agent. For example, as part of the orientation, the metal packaging can be rotated through 180 degrees in order to subsequently cover the area lying opposite this area completely with the coating agent after the bottom area of the metal packaging has been completely covered. In this case, any lid opening can be suitably closed. Alternatively, it is conceivable to allow excess coating material to run out of the metal packaging only under the action of gravity after suitable alignment during the coating process.

In a preferred embodiment of the invention, the metal packaging is pivoted during application or during repeated heating of the coating agent for completely wetting the interior with the on or melted coating agent.

In this way it can be achieved to apply the coating agent by means of a continuous pivoting movement particularly safe and fast on the entire interior of the metal packaging.

The pivoting movement can already take place during the initial application of the coating agent, but also in the context of possible subsequent subsequent steps of heating the applied coating.

According to one embodiment of the invention, the coating composition is mixed with a solvent for paraffin.

This can cause the viscosity of the coating agent and the processing temperature for applying the coating agent to be lowered. Thus, energy savings can be achieved because the coating must not be brought first to a higher processing temperature. Furthermore, by adding solvents to the coating agent, further process-relevant properties can be suitably influenced. It is conceivable that the Creep ability of the coating agent or the adhesion to the specific sheet material can be improved.

It is understood that preferably non-toxic or harmless solvents should be used. Alternatively, it is conceivable that other solvents, e.g. Petrol, ether and chloroform, with excellent solution effect on paraffins can be used. It is further understood that these solvents should completely escape after application, after which the coating agent may have the advantageous properties of approximately or completely pure paraffin.

In this context, it should be noted that the proportion of paraffin on the coating agent may change due to outgassing or other separations of constituents, at least after the production of the metal packaging may be greater than before the application of the coating composition.

It is understood that the features of the invention mentioned above and those yet to be explained below can be used not only in the particular combination indicated, but also in other combinations or in isolation, without departing from the scope of the present invention.

Further features and advantages of the invention will become apparent from the following description of several preferred embodiments with reference to the drawings. Show it:

Figure 1 is a perspective view of a partially cut-open metal packaging according to the invention in the form of a barrel;

Figure 2 is a perspective view of another metal packaging according to the invention in the form of a box; Figure 3 is a perspective view of another invention

Metal packaging in the form of a canister;

Figure 4 shows a section through a metal packaging according to the invention with a folded lid;

Figure 5 is a schematic representation of a system for coating the

Interior of a metal packaging using the method according to the invention;

Figure 6 is a view of a nozzle for use in the invention

Method;

FIG. 7 shows a partial section of an embodiment of a nozzle modified with respect to FIG. 6;

Figure 8 is a schematic partial view of a modified compared to Figure 5

Embodiment of a system for coating a metal container;

FIG. 9 shows an enlarged partial section through a metal packaging according to the invention in the region of a seam connection with a coated coating agent;

FIG. 10 shows a view according to FIG. 9 with an interior of the metal container which is completely wetted by a fused or molten coating agent; and

Figure 11 is a schematic representation of a pivoting device for pivoting or aligning a metal container according to the invention in carrying out the method according to the invention. In Fig. 1, a metal packaging according to the invention in the form of a barrel is shown and designated 10 in total.

Such metal packaging is widely used in the packaging and storage of chemical or technical filling goods or food, especially of beverages. As so-called beer kegs, such designed packages have found wide use. In general, such kegs have a filling volume of about three to about twenty liters, whereby the so-called 5-liter party keg has established itself as a common container size. However, barrels with filling volumes from a few liters up to several hundred liters are mainly offered for wholesale needs or for chemical or technical products.

Such designed metal packaging are usually formed from fine or Feinstblechen. Fines usually have thicknesses of less than 0.5 millimeters, while thin sheets cover approximately the thickness range of 0.5 to 3 millimeters. Common materials and semi-finished products for producing such metal packaging are flat strips, sheets or coils of tinplate, blackplate or else of electrolytically special chromium-plated sheet steel.

The metal packaging 10 shown in FIG. 1 is designed starting from the flat material by various forming and joining processes. The metal packaging 10 has an envelope 12 surrounding an interior 12, which is connected by means of hinge connections 17 in its lower region with a base element 11 and in its upper region with a ceiling element 13. The ceiling element 13 has a filling opening 16, for example for filling beer. The bottom element 11 and the ceiling element 13 may be formed, for example, from pre-punched blanks. The enveloping element 15 is formed from flat strip, wherein the cylindrical shape is generated by bending and joining two end faces of the substantially rectangular starting material by means of a rabbet joint (not shown). Alternatively, it is conceivable to form the enveloping element 15 from a tubular semi-finished product. A metal packaging according to the invention may, in addition to the insertion opening 16, have further openings, for example for the integration of a tap or for ventilation or venting.

As part of the shaping of such a container, a variety of separation, joining or forming processes can be used, in particular punching, cutting, expanding, flanging, folding, welding or beading.

In this context, it should be noted that the term "metal packaging" should not be understood as meaning that the finished packaging or the filled container does not contain any non-metallic constituents. It is common and conceivable to provide plastic-based closures, valves or transport aids, such as handles or edge protectors, so that "metal packaging" should not be understood as limiting in this regard.

FIG. 2 shows a further metal packaging 10a according to the invention. In contrast to the metal packaging 10 shown in FIG. 1, the metal packaging 10a in FIG. 2 is shown in a one-piece state. The sheath element 15 can be formed by expanding or deep-drawing a flat or preformed semifinished product. The type of container shown in Fig. 2 is usually used to contain carbonated drinks, especially beer or cola, but is also used for other filling goods. Such known as beverage cans packaging can be constructed from the above-mentioned steel sheets, alternatively from aluminum sheets, or from a combination of metal material. Common fill levels are about 0.2, 0.25, 0.33, 0.5, 0.75, 1.0 and 1.5 liters.

The usual form of a beer or cola can with a metallic disposable closure requires a production or filling technical feature, a ceiling element (not shown in Fig. 2) is namely only after filling of the filling material in the filling element 15 of the metal packaging 10 a with the enveloping element 15th connected. Another modified embodiment of a metal packaging according to the invention is shown in Fig. 3 and is designated 10b. The metal packaging 10b in the form of a canister can be used to hold liquid chemical products, such as paint or varnish, as well as the storage of free-flowing granules or powder. In the food industry, such containers are used, among other things, for storing edible oil.

In an exemplary configuration, the metal packaging 10b has an enveloping element 15, which also delimits the bottom region of the metal packaging 10b, so that additionally only one ceiling element 13 is provided, which is connected to the enveloping element 15 via a rabbet joint 17. In an alternative embodiment, such a canister can also have an additional fold connection for receiving a floor element, for example analogously to FIG. 1.

In Fig. 4, another metal package 10c is shown. The sectional view clearly shows the design of the rabbet joint 17 for connecting the ceiling element 13 with the enveloping element 15. It is immediately apparent that crimping or folding operations must take place in order to form such a rabbet joint in the enveloping element 15 and the ceiling element 13, as a result of which the individual metal sheets be subjected to high degrees of deformation in these areas.

It should be reiterated that it is known in the art to use the sheets used either in a flat state prior to forming or in a remodeled condition with coatings such as e.g. Decorative coatings or printing or corrosion protection agents to provide. In the areas of the sheets which have high degrees of deformation, these coatings, if they are applied before forming or joining, can be weakened or damaged by these operations.

This disadvantage may be due to alternative or additional coating of the metal packaging, in particular the interior of the metal packaging, after forming and joining are compensated, which, however, increases the production cost and may result in other disadvantages. Thus, it is known, for example, that coating or coating applied to the interior 12 of the metal packaging 10c by drying of conventional paints at high temperatures of about 180 to 200 ° C. produces a coating on the outside 18 of the metal packaging 10c applied decorative paint can be affected or damaged by discoloration or the like.

Alternatively, by omitting this additional inner coating, reduced corrosion protection would have to be accepted in the inner space 12 of the metal container 10c and, in particular, in the region in which individual elements converge to form a seam connection.

According to the invention it is now proposed to apply a coating with a paraffin-based coating agent in the interior of a metal packaging to avoid such disadvantages.

Fig. 5 shows a schematic representation of a plant for carrying out the method according to the invention.

A simplified illustrated metal packaging 10, approximately shaped according to FIGS. 1 to 4, is arranged relative to a coating device designated 20. It is conceivable here that the feed movement and further possible relative movements of the metal packaging 10 with respect to the coating device 20 are produced by a handling device shown schematically in FIG. 5 and designated as a whole by 40. The handling device can have lifting means or rotating means, as indicated by the arrows 46 and 44, respectively, in order to move the metal packaging 10 relative to a nozzle part 24. Alternatively, it is conceivable to move the coating device 20, or at least one of these associated supply means 22 with the nozzle member 24 relative to the metal packaging, which will be explained later in Fig. 8 in more detail.

The supply element 22 serves to supply the nozzle 24 with the coating agent 30. For this purpose, lines 28 are provided, designed in FIG. 5 by way of example as a ring line. It is understood that the feed element 22 may have a valve (not shown) suitable for controlling the coating process. The line 28 connects a container means 34, which serves to receive a supply of the coating agent 30, with the nozzle part 24, wherein excess, not applied coating agent can be introduced via a return in turn into the container means. A pump 35 in the line 28 is used to generate pressure for applying the coating agent 30th

Advantageously, the coating agent 30 is heated or liquefied prior to application by means of heaters 32 or 32a. The heater 32 may serve to heat the coating agent 30 as it flows through the conduit 28. In addition, a heating device 32a is shown, which serves to heat the coating agent 30 located in the container means 34, so that the target temperature of the coating agent 30 can alternatively be ensured by permanent circulation in the line 28 by means of the pump 35.

FIGS. 6 and 7 show structural developments of the supply means 22. In this case, the nozzle part 24a in FIG. 6 has a spherical shape, which ensures that almost the entire space surrounding the nozzle part 24a can be wetted with a coating agent.

In contrast, in FIG. 7, a joint 26 is additionally provided in the nozzle part 24b, which makes it possible to additionally pivot the nozzle part 24b in order to be able to coat regions of a metal packaging which are difficult to access. According to the arrangement in FIG. 5, it is sufficient to move the metal packaging 10 in an axis 46 relative to the nozzle part 24 in order to achieve complete wetting of the interior 12 of the metal packaging 10. In addition, a rotation 44 may be introduced to effect a uniform distribution of the coating agent 30 over the circumference of the interior 12 of the metal package 10.

In contrast, in Fig. 8, a metal package 10 is shown schematically, which has only a relatively small filling opening 16. In this way, in particular the coating of corner regions of the interior 12 of the metal packaging 10 can be made more difficult. This is especially true when using a directional nozzle portion 24, such as a nozzle having a beam angle of only 90 degrees or 180 degrees.

In order to overcome such disadvantages, an alternative handling device 40a is now provided in FIG. 8, which serves to deliver a supply means 22a to the nozzle part 24 into the interior 12 of the metal packaging 10. The handling device 40a may have lifting means or rotating means, as indicated by the arrows 46a and 44a. In this way, the supply means 22a can be introduced into the inner space 12 and also moved there. For fine alignment of the nozzle part 24 further joints 26a, 26b are provided. By combining the handling device 40a with the supply means 22a, it is now possible to wet almost the entire inner space 12 of the metal packaging 10.

FIGS. 9 and 10 now illustrate a particularly advantageous method step.

In each case, the region of a rabbet joint 17 between a bottom element 11 and an enveloping element 15 of a metal packaging is shown in section. This cutout can be representative of areas of other seam joints, more generally for hard to reach areas of a metal packaging. This In particular, cover folds or lateral vertical folds may also be any areas that are not wetted in the context of the initial coating.

The initially applied coating agent 30 'is shown in FIG. 9. It can be seen here that the area in which the enveloping element 15 and the base element 11 meet in order to form a seam connection, a so-called seam channel 19, may not be completely covered by the coating agent due to its narrowness and depth. However, the coating agent 30 'according to the invention can be melted on or melted particularly easily at relatively low temperatures by suitable heat supply, indicated at 38. For this purpose, a melting device 36 is used to generate the heat input 38. The heat input 38 can advantageously via convection, heat conduction and radiation in or around the metal packaging, for example by means of circulation of heated air or by infrared, in particular Nahinfrarotstrahlung. In this case, it is particularly advantageous in terms of manufacturing technology to melt or melt the coating agent 30 'to be heated indirectly by heating sheet metal material 14 in the enveloping element 15 or the bottom element 11.

In this context, it should be mentioned separately that the temperatures occurring on the outside of the metal packaging are significantly lower than the temperatures during the drying of conventional lacquers on the inside of a metal packaging. Thus, damages such as e.g. Color deviations in the coating of the outside of the packaging safely avoided.

10 now illustrates the desired target state, in which the coating agent now designated 30 "has automatically penetrated into the seam channel 19 and wetted it completely, thus also in this area reliable corrosion protection and later separation of the filling material from the sheet metal material 14 The coated or molten coating agent 30 "is sufficiently viscous to ensure that once wetted areas are not re-exposed despite the self-induced gravity bleeding. This particularly preferred method step is also particularly suitable for safely coating inaccessible areas on the outer sides of metal packaging. This can be, for example, pronounced depressions, beads or outer fold geometries. It is known that metal containers tend to corrode in such areas.

In order to support the penetration of the coating agent into hard-to-reach areas of the interior of the metal packaging or even to enable it, it is particularly advantageous to align or swivel the metal packaging suitable, so that by means of gravity-induced flow actually the entire interior can be wetted.

FIG. 11 schematically shows a pivoting device suitable for this purpose, which is designated overall by 42. The pivoting device 42 is provided with different pivot axes 52, 54, 56 and 58. Furthermore, gripping means 50 are provided in order to grip and hold the metal packaging 10. By means of the pivoting device 42, the metal packaging 10 can now be suitably aligned or pivoted in order to direct or promote the flow of the coating agent. This pivoting or alignment can be done both discretely and continuously. Thus, it is conceivable to move the metal packaging 10 already during the heating of the applied coating agent in order to keep the process time short.

As an example of a discrete orientation of a metal packaging 10, it is conceivable to heat a container, for example according to FIG. 1, after the initial application of the coating agent in a position in which the bottom element 11 is located on the floor, so that the coating agent can automatically penetrate into the rabbet channel of the hinge connection 17 between the base element 11 and the enveloping element 15. Thereafter, the metal package 10 can be easily rotated by 180 degrees, so that the coating agent 30, which is still in the fused or molten state, or brought by reheating again in this state, also in the rabbet channel between the ceiling element 13 and Envelope element 15 can penetrate. In this case, the insertion opening 16 can be suitably closed in order to prevent outflow of the molten coating agent 30.

It is also conceivable to introduce a larger amount of coating agent into a metal packaging, to allow it to flow around deliberately in the interior of the metal packaging and then pour out an excess, unnecessary amount of the coating agent from the metal packaging.

It is understood that the handling, swiveling and feeding devices shown can be suitably combined, reduced and simplified in order to make the system for carrying out the method according to the invention as simple and cost-effective as possible and to be able to integrate it in the established production process in the production of metal containers.

In the context of the invention, it has been possible to provide a particularly simple and effective method for producing metal packaging, in which in particular the corrosion protection in the interior of the metal packaging is secured to an improved degree with simultaneously reduced production costs and with improved manufacturing quality.

Accordingly, a metal packaging according to the invention ensures a high degree of corrosion protection with simplified manufacturability, which in particular also meets the requirements for foodstuff authenticity.

Claims

claims

1. Method for producing metal packaging with the following steps:

Molds of a metal packaging (10), in particular of steel or aluminum, of a sheet metal material, in particular of fine or Feinstbzw. Tinplate, with an interior (12) and

Coating the interior (12) with a paraffin-based coating agent (30).

2. The method of claim 1, wherein the coating agent (30) under pressure, in particular by airless spray, applied.

3. The method of claim 1, wherein the coating agent (30) by means of a casting or pouring method is applied.

4. The method according to any one of the preceding claims, wherein the coating agent (30) is heated for coating to a temperature above the solidification temperature.

5. The method according to any one of the preceding claims, wherein the coating agent (30) has a solidification temperature of above 70 ° C, preferably above 85 ° C, more preferably above 90 ° C.

6. The method according to any one of the preceding claims, wherein the coating agent (30) after the coating is heated again to a temperature above the solidification temperature.

7. The method according to any one of the preceding claims, wherein during the forming of the metal packaging (10) at least one rabbet connection ausgebil- Det is coated during the subsequent coating of the interior (12) with the coating agent (30).

8. The method according to any one of the preceding claims, wherein the metal packaging (10) for applying or reheating the coating means (30) for completely wetting the inner space (12) with the coating means (30) is arranged aligned.

9. The method according to any one of the preceding claims, wherein the metal packaging (10) during application or during repeated heating of the coating means (30) for completely wetting the inner space (12) with the fused or melted coating agent (30) is pivoted.

10. The method according to any one of the preceding claims, wherein the coating agent (30) is mixed with a solvent for paraffin.

11. metal packaging of a sheet material, in particular of sheet or Feinst- or tinplate, for receiving a filling in an interior space (12), wherein at least the interior (12) has a surface coating with a coating agent (30) on paraffin-based.

12. metal packaging (10) according to claim 11, wherein the interior (12) by an enveloping element (15) and at least one bottom element (11) or a ceiling element (13) is limited, wherein at least the bottom element (11) or the ceiling element ( 13) is connected by a rabbet joint with the enveloping element (15) and the seaming on the inside (12) is covered by the surface coating.