Method, device and system for production of a metal can with a decorative layer

Abstract

The invention relates to a process for producing a metal can (11), which metal can (11) has a can body (111) with a narrowed can neck (112) and a decorative layer (10) which has been attached to the can body (111). In the first phase of process steps a metal can preform (110) with an undecorated can body (111) and tapered can neck (112) is produced and in a second phase of process steps which takes place later or immediately follows the first phase of the process steps, the metal can preform (110) is provided with a decorative layer (10) which consists preferably of shrinkable material and which has a decoration (100) and is finished. The invention relates furthermore to a device for carrying out this process, to metal cans (11) which can be produced using this process or metal can preforms (110) which can be further processed and to a decorative layer (10) for use in this process.

Description

[0001] The invention relates to a process according to the preambles of claims 1, 2, and 12, to a device for carrying out this process according to the preambles of claim 13 and 14, to a system according to the preamble of claim 17, to a metal can which can be produced using this process and to a metal can preform which can be further processed in this process, and to a decorative layer for use in this process according to the preamble of claim 31.

[0002] Metal cans of aluminum or steel, mainly aerosol cans, are mass-produced products and are made with largely automated devices. Known process for producing these metal cans begin with a pressing process, in which a disk-shaped metal blank is deformed cold in a mold into a can body or a metal sheet is rolled and welded on the ends into a can body. Then the can body is mechanically cleaned by means of brushes, and rinsed or chemically cleaned by means of detergents and clean water so that any mold release agents, shavings, grease and other lubricants are removed. The can body is enamelled inside with a protective paint, this enamel is applied via spray nozzles. The inside enamelling is then dried in an oven. The can body is thereupon worked on the outside; this includes application of a base enamel and drying of the base enamel in an oven, printing of the can body and drying of the printing in an oven, and application of a top enamel and drying of the top enamel in an oven. Finally, the can neck or lower can edge is tapered and flanged on a flanging station. Finally, the metal can is filled with a material, provided with a top and a bottom, and packed for shipping.

[0003] The high energy cost in drying four times, i.e. drying of the inside enamel, the base enamel, the printing and the top enamel and high consumption of solvent for the applied enamels and the associated environmental burden are disadvantageous in this known added value chain in the production of metal cans.

[0004] The applicant in document WO 95/34474 disclosed one approach in this regard. According to it the outside working of the can body is managed by applying a decorative layer. The process steps application of the base enable and drying, printing, and drying as well as application of the top enamel and drying are thus omitted., The decorative layer is for example a shrink foil metal or plastic foil, which is provided with for example an imprinted decoration. It is shrunken on and as a result of its ductility and elasticity can follow the tapering of the neck part of the metal can and thus extends into the neck part. The decorative layer of shrink foil or film due to its smooth surface acts as the lubricant which supports the tapering process and thus takes part in the production of the metal can, i.e. that the metal can with the tapered neck part cannot be produced separately from the decorative layer.

[0005] The disadvantage in this process is that separate production of the metal can and decorative layer is not possible; this breaking of the added value chain is desirable. Furthermore it is disadvantageous in this process that the decorative layer of shrink foil or film can be torn upon subsequent flanging if it is not exactly positioned.

[0006] The object of this invention is therefore to eliminate the disadvantages of what is known. The value added chain in the production of metal cans will be broken and become more flexible. It is also to be possible to flange the metal can without tearing the decorative layer. The invention will be compatible with proven techniques and processes.

[0007] This object is achieved by the invention according to the definition of the claims.

[0008] The object of this invention is achieved in that it uses a decorative layer which can be applied solely by means of adhesion force to a metal can. The concept of adhesion connection is defined in the most general sense of “adhering”. The decorative layer and the metal can can be produced separately. The decorative layer can be easily positioned on the undecorated metal can and applied for example by shrinking on the can body with the can neck already tapered. The invention thus allows the known added value chain to be broken, since the decorative layer is not involved in the production of the metal can.

[0009] The application of the decorative layer by means of adhesion force does not necessarily require clean or grease-free surfaces of the can body. This relative insensitivity to contaminants of the decorative layer also enables the can body to be tapered using the remaining lubricants from preceding process steps, such as shaping of the can body. This process also breaks known value added chains.

[0010] Positioning and attachment of the decorative layer take place before optional flanging of the can neck or lower can edge. The decorative layer then extends into the area of at least one flange which is to be attached and is covered by it. The material of the decorative layer is advantageously perforated in the area of the flange which is to be attached to the metal can. This perforation prevents tearing of the material of the decorative layer as a result of possible damage when the flange is being attached.

[0011] Suitable materials of the decorative layer are fundamentally all those which can be applied to a can body by means of adhesion force. Advantageously materials are used in the form of tubing or flat foil or film. Preferably shrinkable materials are used. Shrinkdown plastic tubing compared to shrink foil or film has the advantage of a much higher elasticity and can thus elastically adapt for example to large diameter changes, as occur for example in the neck area of the can body. Materials which do not shrink or which hardly shrink can likewise be used as long as they are formed for example as tubing or have an elasticity such that they adhere stably to the can body by adhesion force.

[0012] The invention furthermore allows almost unlimited freedom in the configuration of the decoration, since any two-dimensional or three-dimensional decorative layers can be used.

[0013] The decorative layers can also be produced for example “just-in-time”. I.e., that in the first phase unprinted metal can preforms with an undecorated can body and tapered can neck can be produced for example at the metal can manufacturer and for example delivered to the cannery and for example stored. In the second phase these unprinted metal can preforms are provided “just-in-time” with decorative layers, the can neck or lower can edge optionally flanged and the metal cans filled with a substance, and sealed with a top or with a top and a bottom and packed.

[0014] This “just-in-time” allows rapid reaction to one-time events, personalized, direct 1:1 marketing and preparation for future trends. It allows production control in the production of metal cans. In particular it allows starting of the first and second phase of the process steps according to the marketing decision. A certain decoration is selected in a marketing decision or in a sales and marketing office. For example a decoration is loaded by pressing a button “good to print” from a memory and sent for example remotely to the decorative layer printer, whereupon a decorative layer is produced or printed. In the second phase the decorative layer is applied to metal can preforms. This takes place very quickly and with low cost. The decorative layer printer can be at the cannery. The marketing decision dictates the start of the second phase of the process steps. This also allows by marketing decision a corresponding conditioning of the materials to fill the metal cans. For example, they are likewise specially colored “just-in-time”, provided with a special aroma, etc. The finished product can thus be launched very quickly. A customer's wish for small and individually configured coatings can thus also be satisfied without compromises in quality and profit. All this takes place economically and yields competitive advantages.

[0015] The invention is explained below using the figures in embodiments.

[0016] FIG. 1 shows a first example of the process sequence for producing metal cans,

[0017] FIG. 2 shows a second example of the process sequence for producing metal cans,

[0018] FIG. 3 shows a third example of the process sequence for producing metal cans,

[0019] FIG. 4 shows a fourth example of the process sequence for producing metal cans,

[0020] FIG. 5 shows a part of the first sample embodiment of a decorative layer for use in the process for producing a metal can,

[0021] FIG. 6 shows a part of the second sample embodiment of a decorative layer for use in the process for producing a metal can,

[0022] FIG. 7 shows a part of the first sample embodiment of a metal can preform produced using the process,

[0023] FIG. 8 shows a part of the first sample embodiment of a metal can producing using the process, with a flanged nozzle neck,

[0024] FIG. 9 shows a part of the second sample embodiment of a metal can preform produced using the process,

[0025] FIG. 10 shows a part of the second sample embodiment of a metal can producing using the process, with a flanged nozzle neck,

[0026] FIG. 11 shows a part of a sample embodiment of a metal can flange produced using the process,

[0027] FIG. 12 shows a part of a sample embodiment of a device for positioning and applying a decorative layer to metal cans,

[0028] FIG. 13 shows a part of a sample embodiment of known value creation in the production and filling of metal cans,

[0029] FIG. 14 shows a part of the first sample embodiment of a value creation in the production and filling of metal cans produced using the process,

[0030] FIG. 15 shows a part of another sample embodiment of value creation at the producers of the metal cans produced using the process and the canneries,

[0031] FIG. 16 shows a part of another sample embodiment of a metal can preform produced using the process,

[0032] FIG. 17 shows a part of another sample embodiment of a metal can produced using the process, with a flanged can neck and flanged lower can edge.

[0033] The invention relates to a process for producing a metal can, which metal can has a body with a narrowed can neck and a decorative layer which is attached to the can body. In the first phase of process steps a metal can preform with an undecorated can body and tapered can neck is produced and in a second phase of process steps which takes place later or immediately follows the first phase of process steps, the metal can preform is provided with a decorative layer of preferably shrinkable material which has a decoration and is completed. The invention relates furthermore to a device and a system for carrying out this process, to metal cans which can be produced using this process or metal can preforms which can be further processed, and to a decorative layer of preferably shrinkable material for use in this process.

[0034] FIGS. 1 to 4 show four sample process sequences for producing a metal can. These sequences set nine or eleven process steps which are largely automated and which are carried out in sequence.

[0035] Process step 1 designates “production of a can body”. For example, a disk-shaped metal blank is shaped by a pressing device in a mold into for example a cylindrical can body with an opening. For example a metal sheet is rolled and the ends are welded by a welding device into a for example cylindrical can body with two openings. Metals can be aluminum or steel and alloys with aluminum or steel. With knowledge of this invention one skilled in the art is free to use other metals for pressing or welding a can body.

[0036] Process step 2 designates “brushing of the can body”. This is mechanical cleaning with a cleaning device, for example with oscillating brushes for removing any mold release agents, shavings, grease and other lubricants. Generally trimming of the can body also takes place. Following this is process step 3 “washing the can body” by means of detergents or clean water in order to obtain clean and grease-free surfaces.

[0037] Process step 4 relates to “inside enamelling of the can body”, enamel being applied via an enamelling device for example via suitable shaped spray nozzles to the inside surfaces of the can body. The use of nozzles for inside enamelling is advantageous since these nozzles can be inserted into highly tapered, for example 50% tapered neck areas of drawn can bodies. Process step 5 sets the subsequent “drying of the inside enamelling” by a drying device, for example by a circulating air drier or by irradiation with UV light.

[0038] Process step 40 is optional; it relates to at least partial “base enamelling of the outside surfaces of the can body”, enamel being applied via an enamelling device for example via suitably shaped spray nozzles to the outside surfaces of the can body. Process step 50 is likewise optional and sets subsequent “drying of the base enamelling” by a drying device, for example by a circulating air drier or by irradiation with UV light. Process steps 40 and 50 are optional; the presence of base enamelling reduces surface roughness, the surface of the base-enamelled can body is smoother than that of a raw metallic can body. This is not important to the attachment of the decorative layer, a decorative layer can be attached directly to the metallic can body or indirectly to the base enamelling of the outside surfaces of the can body.

[0039] In process step 6 “tapering of the can neck or at least an indentation” in which at least partial narrowing of the neck 112 of the can body 111 by for example 2% or even 50% is done from the outside with the tapering device. In the same process step 6 further radius narrowing or radius widening as at least one indentation 113 can be made on the metal can preform. The embodiment of a metal can preform 110 as shown in FIG. 9 and that of a metal can 111 produced from it as shown in FIG. 10 show for example one such indentation 113 made on the can body 111 for better gripping of the metal can. In the understanding of this invention the can neck 112 can be tapered or at least one indentation formed on the can body 111. Here “or” means that formation of an indentation 113 on the can body is optional and can take place in addition to tapering of the neck 112 of the can body 111.

[0040] As is apparent from the added value chain as shown in FIGS. 1 to 4, the tapering of the can neck 112 can take place before or after inside enamelling (versions as shown in FIGS. 1 and 2) or before or after optional base enamelling (version according to FIGS. 3 and 4). If tapering of the can neck in the process sequence as shown in FIG. 2 or FIG. 4 takes place before “brushing of the can body”, “washing of the can body” and “inside enamelling of the can body”, residual lubricants from preceding process steps which have not yet been chemically removed, for example from pressing of the can body, can be used to benefit for shaping. If necessary, additional lubricants can also be applied to carry out tapering of the can neck, which residual lubricants or additional lubricants are completely removed in the following washing. It is advantageous in this process as shown in FIG. 2 or FIG. 4 that smaller demands with respect to elasticity are imposed on the enamel of the inside and outside enamelling since it is applied after tapering of the can neck. If tapering of the can neck takes place as in the process sequence shown in FIG. 3 or FIG. 4 after “base enamelling of the outside surfaces of the can body”, the smoother surface of the can neck resulting from base enamelling can be used to benefit during tapering of the can neck. The tapering of the can neck is simplified by smooth surfaces.

[0041] At least process steps 1 and 6 form a first phase in the production of a metal can by producing a metal can preform which can be further processed. These metal can preforms 110 shown by way of example in three embodiments in FIGS. 7, 9 and 16 with can bodies 111 and tapered can neck 112 are an intermediate product which can be stored or transported. In particular, one such metal can preform 110 which has been produced according to process steps 1 and 6 can be sold on the world market among metal can manufacturers and transported for example to the cannery and for example stored.

[0042] At least the process step 7 forms a second phase in the manufacture of a metal can in which a metal can preform is further processed. For example, FIGS. 8, 10 and 17 show three embodiments of metal cans 11 with can bodies 111 and tapered can neck 112. Optionally the can neck 112 and lower can edge 114 can be flanged (process step 8). Finally, the metal can 11 is filled for example with a substance, for example sealed with a top or with a top and bottom and packed (process step 9).

[0043] The decoration can be printed beforehand in any process on tubing or flat film or foil or shrinkdown plastic tubing. Examples are digital printing, flexographic printing, intaglio printing, etc. which make it possible to print pictures, text, graphics, tables, etc. from the rear, onto the back of a decorative layer of an at least partially transparent material of the decorative layer, which printed decorative layer back comes to rest on the can body after positioning, by which the decoration is chemically and mechanically protected by the material itself of the decorative layer, i.e. by its decorative layer front. The thickness of these decorative layers is 0.01 mm to 0.1 mm, typically 0.05 mm. With knowledge of this invention one skilled in the art is free to use other printing processes for printing of decorative layers. Thus UV flexographic printing processes can be used, also the most diverse decorations can be used for any different metal can shapes. The decorations need not be two-dimensional (flat material), they can also be three dimensional (relief structures in a for example 1 mm thick material). Here with knowledge of this invention one skilled in the art is also free to use differently shaped materials.

[0044] In process step 7, positioning and attachment of a decorative layer to the metal can preform take place. To do this material which has been printed beforehand and which has been cropped accordingly is attached to the can body. One such decorative layer 10 with a decoration 100 is shown in FIGS. 5 and 6 by way of example. FIG. 5 shows by way of example a decorative layer 10 in the form of tubing. FIG. 6 shows by way of example a decorative layer 10 in the form of a foil or film. The outside diameter of the can body and the inside diameter of the decorative layer are matched to one another such that the decorative layer adheres to the can after attachment based solely on its own elasticity. As claimed in the invention the decorative layer is attached to the can body by an adhesion connection. The concept of adhesion connection is defined in the most general sense of “adhering”. Adhesion connections in this sense include for example spot and line weld connections mainly on the foil ends, shrinking-on of shrinkable materials, but also contact and pressure cementing. The decorative layer 10 can be attached directly to the metal can body or indirectly to the base enamelling of the outside surfaces of the can body.

[0045] The decorative layer 10 consists at least partially of plastic. Plastics are for example modified vinyl compounds such as polyvinyl alcohol and/or vinyl copolymers and/or other additives which improve toughness values, such as maleic acid anhydride (for example as graft copolymers) and/or urethane and/or styrene. Polyurethanes and/or polyurethane copolymers can be used for the process as claimed in the invention, as can polyolefins such as polyethylene. With knowledge of this invention one skilled in the art can implement diverse variations and combinations of these plastics as decorative layers for metal cans.

[0046] The decorative layer 10 consists advantageously of materials in the form of tubing or a flat film or foil. Preferably shrinkable materials are used. Shrinkdown plastic tubing compared to shrink film or foil has the advantage of much higher elasticity of up to 70% compared to 10% in shrink foil or foil and can be elastically matched for example to large diameter changes such as occur for example on the can neck 112 of the can body 111 with often 50% radius narrowing. Materials which do not shrink or which hardly shrink can likewise be used as long as they are formed for example as tubing or have an elasticity such that they adhere stably to the can body by adhesion force.

[0047] The device for positioning and attachment of the decorative layer to metal cans consists in this sample embodiment as shown in FIG. 12 of a cutting device 21 which cuts the preprinted tubing or foil or film for example as continuous product 101 into the corresponding lengths. The ends of the films or foil are joined to make tubing, advantageously by cementing or welding a joining seam. For example, the device consists of an applicator 22 which slips the individual decorative layers 10 in the form of tubing over the can bodies 111. And it consists for example of a fixing device 23 which fixes on the can bodies the tubing which has been positioned in this way on the can bodies. For example, shrinkdown plastic tubing is [sic]. For example, shrinking-on takes place with heat or steam in a shrinking tunnel. In this way continuously delivered metal can preforms 110 can be provided with a decorative layer. For example, decorative layers of shrinkable material are shrunken onto the can bodies in a shrinking tunnel in a stream of hot air or steam of roughly 140 to 160° C. In doing so the shrinkdown plastic tubing or the shrink film or foil is shrunken tightly onto the can body and adheres to it solely by adhesion forces. With knowledge of this invention one skilled in the art has available diverse possibilities of variation of this positioning and attachment of a decorative layer on metal cans.

[0048] In an optional process step 8 the can neck 112 or lower can edge 114 is flanged. This flanging of the can neck 112 takes place for example in containers with tops as shown in FIGS. 8 and 10, such as aerosol containers, in order to thus mold the top closure onto the can body. These containers are often, but not necessarily made of aluminum as the metal. This flanging of the can neck 112 and the lower can edge 114 takes place for example in containers with tops and bottoms as shown in FIG. 16 in order to attach a top closure and a bottom closure to the can body in this way. These containers are often, but not necessarily made of steel as the metal. FIG. 11 shows one part of a sample embodiment of a flange 12 of a metal can 11. FIGS. 8, 10 and 17 show one part of other sample embodiments of a flange 12 of a metal can 11. This flanging of the edge of the can neck 112 of the metal can 11 for example with a flanging device 24 is known to one skilled in the art in one embodiment as shown in FIG. 12. One advantage of this invention is that the decorative layer 10 extends into the tapered can neck 112 or into the can edge 114 as far as into the area of the flange 12 which is to be attached and is covered at least in areas by this flange 12. For example, the decorative layer 10 of shrunken-on shrinkdown plastic tubing or shrink foil or film follows this flanging due to its elasticity without problems. In order to limit possible damage to the decorative layer 10 during flanging, the decorative layer has perforations 13 at least in areas, wherever it is positioned and attached to the flange which is to be attached on the metal can. These perforation 13 form a tear boundary in the decorative layer such that for possible tearing of the decorative layer 10 in the area of the flange the tubing or the film or foil tears only up to a perforation 13. By making a host of perforations 13 this damage can be minimized such that it is not perceived by the consumer as aesthetically disadvantageous. These perforation 13 can be made in the decorative layers 10 in diverse ways. For example, these perforation 13 are made during printing and cropping of the decorative layers 10. In the sample embodiment as shown in FIGS. 5, 8, 10 and 17 perforations 13 are made as a single line at a constant distance from the end area of the decorative layer 10, in the sample embodiment as shown in FIG. 6 perforations 13 are made as two single lines offset to one another at a constant distance from one end area of the decorative layer 10. In the sample embodiment as shown in FIG. 11 the perforations 13 as patterns are made in the end area of the decorative layer 10. These perforations 13 can be produced mechanically, for example by means of needles, in the decorative layer 10. With knowledge of this invention one skilled in the art is free to make these perforations 13 in a certain pattern, for example as a single or multiple line, or in a honeycomb pattern, and/or in a certain depth, for example partial and/or passing completely through and/or with a certain diameter, for example 0.5 mm in the decorative layer 10.

[0049] In the optional process step 9 the metal cans 11 provided with flanges 13 are packed. The metal cans 11 can be empty or filled with a material and can be packed provided with a top or with a top and bottom.

[0050] FIG. 13 shows the traditional value creation in the production of metal cans, where at the metal can manufacturer for example the printing of the decorative layer and the application of the decorative layers to metal can preforms take place with the can neck not tapered. The designers of the decoration and the film or foil and tubing supplier of unprinted foils or films or tubing are used as the suppliers. The metal cans are delivered to a cannery, filled there and travel to the market for the end consumer.

[0051] The use of decorative layers which can be produced separately and which are positioned in a single, rapid process step on metal cans and which are connected only via adhesion force at the same time allows a prompt product change at the cannery, as shown in FIGS. 14 and 15 on two sample value creations. In the first phase unprinted metal can preforms are produced at the metal can manufacturer and delivered to the cannery and stored there and/or are stored at the metal can manufacturer. Films and foils or tubing which have not been printed by a film or foil and tubing supplier are delivered to the decorative layer printing plant and/or to the cannery. In the second phase these unprinted metal can preforms are provided with the decorative layers “just-in-time”, the can neck or the lower can edge being optionally flanged and the metal cans filled with a substance, sealed and packed.

[0052] Thus there is a system which consists of a metal can preform 110 produced in a first phase with an undecorated can body 11 with a narrowed can neck 112 and of a decorative layer 10 of a shrinkable material provided beforehand with a decoration 100, and this system comprises an applicator 22 in order to position the decorative layer 10 on the can body 111.

[0053] This just-in-time production process at canneries based on prefabricated undecorated metal can preforms stored there allows rapid reaction to one-time events, personalized, direct 1:1 marketing and preparation for future trends. This allows production control in the production of metal cans. In particular this allows starting of the first and second phase of process steps according to a marketing decision. The two sample value creations as shown in FIGS. 14 and 15 show how according to the marketing decision a certain decoration of a designer is chosen and decorative layers are produced in the decorative layer printing plant and/or at the cannery. One such marketing decision is made for example in a sales or marketing office. The marketing decision is manifested in that for example by pressing a button “good to print” a certain selected decoration is loaded from a memory and for example sent remotely to the decorative layer printing plant and/or to the cannery, where the decorative layers are produced, for example printed, and are attached to the metal can preforms at the cannery. This remote sending takes place very quickly for example in an electronic network by the Internet at low cost. The start of the second phase of process steps takes place according to the marketing decision. Optionally the corresponding conditioning of the materials to be placed in these metal cans takes place according to the marketing decision, for example they are likewise specially colored “just-in-time”, provided with a special aroma, etc. The metal cans optionally provided with a flanged can neck or a flanged lower can edge are filled with a substance, provided with a top or with a top and bottom and packed so that the finished product can be launched very quickly into commerce at the final consumer. Also a customer's wish for small and individually configured coatings can thus be satisfied without compromises in quality and profit. All this takes place economically and yields competitive advantages.

Claims

1. Process for producing a metal can (11), which metal can (11) has a can body (111) with a narrowed can neck (112) and a decorative layer (10) which has been attached to the can body (111), characterized in that in the first phase of process steps a metal can preform (110) with an undecorated can body (111) and tapered can neck (112) is produced and that in a second phase of process steps which takes place later or immediately follows the first phase of process steps, the metal can preform (110) is provided with a decorative layer (10) of preferably shrinkable material which has a decoration (100) and is completed.

2. Process for producing a metal can preform (110) which can be further processed, wherein in the first phase of process steps the metal can preform (110) is shaped as an undecorated can body (111) from a metal blank and the can neck (112) of the undecorated can body (111) is tapered and wherein in the second phase of the process steps the metal can preform (110) can be provided with a decorative layer (10) of preferably shrinkable material which has a decoration (100).

3. Process as claimed in claim 1 or 2, wherein the can neck (112) or lower can edge (114) and the decorative layer (10) attached to the can body (111) are flanged at least in areas with a flange (12).

4. Process as claimed in claim 3, wherein the decorative layer (10) which is provided at least in areas with perforations (13) is attached to the can body (111) with these perforation (13) in the area of the flange (12) to be attached to the can neck (112) or to the lower can edge (114) such that the decorative layer (10) when damaged during flanging tears as far as a perforation (13).

5. Process as claimed in claim 1 or 2, wherein the decorative layer (10) is attached to the can body (111) with a two-dimensional decoration (100) or a three-dimensional decoration (100).

6. Process as claimed in claim 1 or 2, wherein the decorative layer (10) is provided with a decoration (100) on the back of the decorative layer and is attached with the back of this decorative layer to the can body (111) such that the front of the decorative layer is used as chemical and mechanical protection.

7. Process as claimed in claim 1 or 2, wherein the decorative layer (10) consists preferably of shrinkdown plastic tubing or a shrink film or foil which is joined into a tube and is positioned by being pulled over the can body (111).

8. Process as claimed in claim 1 or 2, with a can body (111) to which lubricants are applied for shaping from a metal blank, wherein the lubricants are also used to benefit for lubrication when tapering the can neck (112) or for at least one indentation (113) on the can body (111).

9. Process as claimed in claim 1 or 2, wherein the can neck (112) or an indentation (113) on the can body (111) is tapered after outside base enamelling of the can body (111) and wherein the can neck (112) which is provided with a smooth surface by base enamelling is used to advantage when the can neck (112) is tapered or for at least one indentation (113) on the can body (111).

10. Process as claimed in claim 1 or 2, wherein the can body (111) is internally enamelled before or after tapering of the can neck (112) or at least one indentation (113) on the can body (111).

11. Process for production control in the manufacture of a metal can (11), which metal can (11) has a can body (111) with a narrowed can neck (112) and a decorative layer (10) which has been attached to the can body (111), wherein in the first phase of process steps at the metal can manufacturer a metal can preform (110) with an undecorated can body (111) and tapered can neck (112) is produced and

wherein in a second phase of process steps at the metal can manufacturer or at the cannery the metal can preform (110) is provided with a decorative layer (10) of preferably shrinkable material which has a decoration (100) and is completed.

12. Process as claimed in claim 11, wherein the order to produce a decorative layer (10) which has a decoration (100) is issued according to a marketing decision and wherein the order to start the second phase of the process step is issued according to a marketing decision.

13. Device for producing a metal can (11), which metal can (11) has a can body (111) with a narrowed can neck (112) and a decorative layer (10) which has been attached to the can body (111), wherein there is an applicator (22) in order to position a decorative layer (10) of preferably shrinkable material which is provided with a decoration (100) on the undecorated can body (111) with a narrowed can neck (112).

14. Device for producing a metal can preform (110) which can be further processed, wherein there is a pressing device to shape a can body (11) out of a metal blank and wherein there is a tapering device to taper the can neck (112) of the undecorated can body (111).

15. Device as claimed in claim 13 or 14, wherein there is an applicator (22) for pulling the tubular decorative layer (10) consisting preferably of shrinkdown plastic tubing or flat shrink film or foil over the can body (111).

16. Device as claimed in claim 15, wherein there is a fixing device (23) to shrink the decorative layer (10) of shrinkable material with heat or steam onto the can body (111).

17. System consisting of a metal can preform (110) produced in a first phase with an undecorated can body (111) with a narrowed can neck (112) and of a decorative layer (10) of preferably shrinkable material which has been provided beforehand with a decoration (100), the system comprising an applicator (22) to position the decorative layer (10) on the can body (111).

18. Metal can (11), produced using the process as claimed in claim 1 or 2, wherein the decorative layer (10) consists preferably of shrinkable material and a tube which has been attached and positioned on the can body (111) is preferably shrinkdown plastic tubing or a flat shrink film or foil.

19. Metal can (11), with a can body (111) which has a narrowed can neck (112) and with a decorative layer (10) provided with a decoration (100), wherein the decorative layer (10) consists preferably of shrinkable material and a tube which has been attached and positioned on the can body (111) is preferably shrinkdown plastic tubing or a flat shrink film or foil.

20. Metal can preform (110), which can be produced using the process as claimed in claim 2, wherein it has an undecorated can body (111) with a narrowed can neck (112) and at least one indentation (113) on the can body (111).

21. Metal can preform (110), wherein it has an undecorated can body (111) with a narrowed can neck (112) and at least one indentation (113) on the can body (111)

22. Metal can (11) as claimed in claim 18 or 19 or metal can preform (110) as claimed in claim 20 or 21, wherein the decorative layer (10) consists preferably of shrinkable material and is provided at least in areas with perforations (13).

23. Metal can (11) as claimed in claim 18 or 19 or metal can preform (110) as claimed in claim 20 or 21, wherein the decorative layer (10) consists of plastic.

24. Metal can (11) or metal can preform (110) as claimed in claim 23, wherein the decorative layer (10) consists at least in part of modified vinyl compounds and/or of polyvinyl alcohol and/or of vinyl copolymers and/or of maleic acid anhydride and/or of urethane and/or of styrene and/or of polyurethane and/or polyurethane copolymers and/or polyolefins like polyethylene.

25. Metal can (11) as claimed in claim 18 or 19 or metal can preform (110) as claimed in claim 20 or 21, wherein the decorative layer (10) has a two-dimensional decoration (100) or a three-dimensional decoration (100).

26. Metal can (11) as claimed in claim 18 or 19, wherein the decorative layer (10) attached to the can body (111) is flanged at least in areas by a flange (12).

27. Metal can also claimed in claim 26, wherein the decorative layer (10) which is provided at least in areas with perforations (13) is attached to the can body (111) with these perforations (13) in the area of the flange (12) to be attached to the can neck (112) such that when damaged during flanging of the can neck (112) it tears as far as a perforation (13).

28. Metal can (11) as claimed in claim 18 or 19, wherein the decorative layer (10) is provided with a decoration (100) on the back of the decorative layer and is attached with the back of this decorative layer to the can body (111) such that the front of the decorative layer is used as chemical and mechanical protection.

29. Metal can (11) as claimed in claim 18 or 19 or metal can preform (110) as claimed in claim 20 or 21, wherein the can body (111) consists of aluminum or steel or an alloy of aluminum or steel.

30. Metal can (11) produced as claimed in one or more of claims 1 to 12.

31. Decorative layer (10) for use in the process as claimed in one of claims 1 to 12, wherein the decorative layer (10) consists preferably of a shrinkable material and if necessary can be positioned and attached to the can body (111).