DE19961411A1 - Process for the production of coated metal surfaces and their use - Google Patents

Abstract

The invention relates to a method for producing coated metal surfaces at a coating speed of at least 25 m per minute during the application of a pre-treating agent to a cleaned and/or pickled metal surface. The inventive method is characterized by applying at least one pre-treating agent to at least one surface of a metal body after cleaning and/or pickling the metal surface to be treated. At least one lacquer layer is applied to a part of the pre-treated surface, the coating produced only by the pre-treating agent and not by the lacquer being used as the treatment layer instead of a priming or pre-treatment layer. The invention further relates to a method for producing coated metal surfaces at a coating speed of at least 25 m per minute during the application of a pre-treating agent to a cleaned and/or pickled metal surface. The inventive method is characterized by applying at least one pre-treating agent to at least one surface of a metal body after cleaning and/or pickling the metal surface to be treated. At least one lacquer layer is applied to at least a part of the pre-treated surface, the coating produced only by the pre-treating agent being used as the treatment layer instead of a priming or pre-treatment layer.

Description

The invention relates to a method for producing coated Metal surfaces where coating takes place at high speed can. Such coatings are known today under the term "coil coating" Coating of tapes used.

The known high-speed coating processes have the disadvantage on that pretreatment and priming in two separate steps be applied.

The object of the invention is to provide a process for the industrial production of to propose painted tapes, in which the pretreatment and priming in can only be applied in one operation.

The object is achieved by a process for the production of coated Metal surfaces with a coating speed of at least 25 m per Minute when applying a pretreatment agent to a cleaned or / and pickled metal surface, which is characterized in that on at least one Surface of a metallic body after cleaning and / or pickling metallic surface to be treated at least one pretreatment agent, in particular a solution and / or dispersion, is applied and then on applied at least one layer of lacquer to part of the pretreated surface is, the only with a pretreatment agent and not with a varnish produced coating as a treatment layer instead of a pre-treatment and a primer layer is used.

Furthermore, the object is achieved by a method for producing coated metal surfaces at a coating speed of  at least 25 m per minute when applying a pretreatment agent on a cleaned or / and pickled metal surface, which is characterized in that on at least one surface of a metallic body after cleaning or / and pickling the metallic surface to be treated at least one Pretreatment agent, in particular a solution and / or dispersion, applied and then on at least part of the pretreated surface at least one layer of lacquer is applied, the one with a Pre-treatment agent treated coating instead of as a treatment layer a pre-treatment and a primer layer and is used.

The pretreated surface or the pretreated surfaces preferably becomes one Side of a band, in which at least one of the narrow ones, if applicable Edge areas of the tape can be partially pretreated.

The coating speed is preferably 40 to 600 m per minute, particularly preferably 75 to 160 m per minute. The treatment layer takes over the functions of the primer. The other part of the pretreated The surface is subsequently no longer applied to the coil coating system with a Lacquer covered.

The inventive method can be used so that moisture or Preserve residual moisture in the applied pre-treatment layer until painting remains to the necessary electrical conductivity for the application of the lacquer layer of the pretreated surface.

Before the pretreatment, the metal surface can be aluminum, iron, Contain copper, magnesium, zinc and / or tin and can preferably be from a Aluminum alloy, hot-dip galvanized or electrolytically galvanized Iron material, a steel, a solid zinc material in the form of strips or Sheet or tinplate exist. The body can be flat or be deformed without or with recesses such. B. provided with a hole structure  his. The recesses of a perforated plate can all be the same or possibly also have different geometries and sizes: e.g. circular holes, Slots, slots.

The cleaning and / or pickling of the metallic surface can be done by spraying or / and brushing with a cleaning or pickling solution or immersing in a bath this solution.

The pretreatment of the cleaned and / or pickled surface can be carried out by Spray and squeeze z. B. with a roller, by spraying and blowing e.g. B. with compressed air, by diving and squeezing z. B. with a roller Diving and blowing off e.g. B. with compressed air or in the roll coat process. At the Roll-coat process the treatment liquid with a coating roller or applied against the tape running direction. With all of these Process variants, no subsequent rinsing is carried out to remove or to avoid damage to the applied layer and in order to Avoiding chemical-contaminated rinsing water, which is expensive for environmental reasons need to be treated.

The pretreatment agent can be a preparation which is a polymer dispersion with at least one resin from the group of acrylate, epoxy, phenol, polyester, Silicone polyester, polyurethane, styrene and resin based on urea-formaldehyde or their mixture or / and copolymer. The preparation contains in addition to volatile components, a non-volatile film-forming mixture. The preparation can contain at least one resin as a solution and / or as a dispersion. The In addition to resin (s), the preparation can contain at least one inorganic additive in solution Form or / and as a finely divided powder such. B. a carbonate, chromate, oxide, Contain phosphate, silicate, sulfate.

The pretreatment agent can also be a resin-free preparation, the Preparation aluminum, fluoride, hydrofluoric acid, phosphate, phosphoric acid, tri- or lund  hexavalent chromate, chromic acid, silicate, silane, tannin, titanium, zinc, zirconium or / and self-organizing molecules z. B. based on phosphonates, Can contain carboxylic acids, thiols and / or silanes.

For the application on a metallic band one side of the band can be used different pretreatment agent are chosen than for the other side, the side not intended for subsequent painting with an organic resin containing pretreatment agent can be coated. Here, for. B. only one side of a volume - e.g. B. the top - painted while on the on the opposite side, the pre-treatment acts as a final treatment.

After application of the treatment agent, the layer can either be partially dried or thoroughly dried. This can - especially with the same Belt speed and when using existing furnaces - by a shorter one Residence time under the active drying conditions, due to a lower one Temperature in the oven and / or by a lower air movement for drying the Band are implemented.

At least one side of the pretreated surface is preferably covered with a organic coating coated in a time from 1 second to 3 Minutes sufficiently hardened or crosslinked, particularly preferably in a time of 5 Seconds to 2 minutes.

A powder coating is preferred for coating the pretreated surface applied and baked, especially a powder coating with good mechanical Properties, high scratch resistance, good adhesion and high flexibility in terms of the transformation. The powder coating can be sprayed, fluidized bed or / and Powder Cloud Technology can be applied or burned in. The powder cloud Technology is u. a. in EP-A-0 678 466. Branding can take place instead the conventional circulating air drying or suspended circulating air drying in particular  by conductive drying for magnetic materials or by Infrared drying, especially in the near infrared (NIR).

The pre-treatment or treatment layer can after complete drying have a layer thickness in the range from 0.1 to 50 μm, preferably in the range from 0.5 to 10 µm, very particularly preferably in the range from 1 to 3 µm.

The burned-in lacquer layer, which is located on the pretreatment layer, can have a layer thickness in the range from 5 to 1000 μm after crosslinking, preferably in the range from 10 to 400 μm, very particularly preferably in the range from 15 to 60 µm. When using PVC plastisols it can be recommended to choose a layer thickness in the range of 100 to 300 µm.

In a preferred embodiment, the method according to the invention uses a Single-layer topcoat applied as the only lacquer to the tape to be coated.

A treatment layer can be formed with the pretreatment agent the function of a pre-treatment and at the same time a primer takes over. The primer takes on the function of Corrosion protection, liability and flexibility met, but not in stronger Measure also an aesthetic function.

A powder for a monochrome, unstructured coating can be used in the powder coating Powder for a multicolored unstructured coating and / or a powder for one multicolored textured coating can be used.

The coated surface can be at least partially covered by a film or Adhesive film are protected, in particular from mechanical damage such. B. during storage, transportation and further processing.  

The coated bodies can optionally be deformed, cut - in particular cut lengthways and / or crossways - and if necessary be deformed again, such as. B. flanged, roll-formed, deep-drawn or / and be folded.

The products produced by the process according to the invention can be used as Interior and exterior cladding, equipment cladding z. B. for household appliances and Small electrical appliances, in particular with decorated outer cladding, perforated sheets especially for loudspeakers and soundproofing panels, room dividers, Partitions, furniture elements, shelves, vehicle and aircraft interior linings such as B. dashboards, frames and frame constructions, facings, Lighting fixtures can be used.

Claims (23)

1. Process for the production of coated metal surfaces at a coating speed of at least 25 m per minute, in particular at a coating speed in the range from 40 to 600 m per minute, preferably from 75 to 160 m per minute, when applying a pretreatment agent to a cleaned or / and pickled metal surface, characterized in that at least one pretreatment agent, in particular a solution and / or dispersion, is applied to at least one surface of a metallic body after cleaning or / and pickling of the metallic surface to be treated, and then on part of the pretreated At least one lacquer layer is applied to the surface, the coating produced only with a pretreatment agent and not with a lacquer being used as the treatment layer instead of a primer and pretreatment layer. 2. Process for the production of coated metal surfaces at a Coating speed of at least 25 m per minute, in particular at a coating speed in the range of 40 to 600 m per minute, preferably from 75 to 160 m per minute when applying one Pretreatment agent on a cleaned or / and pickled metal surface, characterized in that on at least one surface of a metallic Body after cleaning and / or pickling the to be treated metallic surface at least one pretreatment agent, in particular a solution and / or dispersion, is applied and then to at least part of the pretreated surface at least one layer of paint is applied, the treated with a pretreatment agent Coating as a treatment layer instead of a primer and Pretreatment layer is used.   3. The method according to claim 1 or 2, characterized in that the Moisture or residual moisture in the applied pre-treatment layer up to is obtained for painting, for applying the paint layer adjust the necessary electrical conductivity of the pretreated surface. 4. The method according to any one of the preceding claims, characterized in that the metal surface before pretreating aluminum, iron, copper, Contains magnesium, zinc and / or tin and preferably from a Aluminum alloy, hot-dip galvanized or electrolytic galvanized iron material, a steel, a solid zinc material in the form of Strips or sheets or tinplate. 5. The method according to any one of the preceding claims, characterized in that cleaning or / and pickling by spraying and / or brushing with a cleaning or pickling solution or immersion in a bath of this solution he follows. 6. The method according to any one of the preceding claims, characterized in that the pretreatment agent by spraying and squeezing z. B. with a Roller, by spraying and blowing z. B. with compressed air, by diving and Squeezing, by dipping and blowing off or in the roll-coat process is applied. 7. The method according to any one of the preceding claims, characterized in that that the pretreatment agent is a preparation that is a polymer dispersion with at least one resin from the group of acrylate, epoxy, phenol, Based on polyester, silicone polyester, polyurethane, styrene and resin Contains urea-formaldehyde or their mixture or / and copolymer.   8. The method according to any one of the preceding claims, characterized in that the pretreatment agent is a preparation that as at least one resin Contains solution or / and as a dispersion. 9. The method according to any one of the preceding claims, characterized in that the pretreatment agent is a preparation that in addition to resin (s) at least one inorganic additive in dissolved form and / or as finely divided powder such. B. a carbonate, chromate, oxide, phosphate, silicate, Contains sulfate. 10. The method according to any one of the preceding claims, characterized in that the pretreatment agent is a resin-free preparation that contains aluminum, Fluoride, hydrofluoric acid, phosphate, phosphoric acid, tri- or / and hexavalent Chromate, chromic acid, silicate, self-organizing molecules, silane, tannin, Contains titanium, zinc and / or zirconium. 11. The method according to any one of the preceding claims, characterized in that that for the application to a tape for one side of the tape another Pretreatment agent is chosen as for the other side, the not for Subsequent painting provided with an organic resin containing pretreatment agent can be coated. 12. The method according to claim 6, characterized in that with the Pre-treatment agent applied layer either partially dried or is thoroughly dried. 13. The method according to any one of the preceding claims, characterized in that at least one side of the pretreated surface with an organic Coating is coated in a time from 1 second to 3 minutes sufficiently cured or crosslinked, preferably in a time of 5 seconds up to 2 minutes.   14. The method according to claim 13, characterized in that for the coating a powder coating is applied to the pretreated surface and baked, especially a powder coating with good mechanical properties, high Scratch resistance, good adhesion and high flexibility in terms of forming. 15. The method according to any one of the preceding claims, characterized in that the powder coating by spraying, fluidized bed or / and powder cloud Technology is applied or baked. 16. The method according to any one of the preceding claims, characterized in that the pretreatment or treatment layer after complete Drying has a layer thickness in the range from 0.1 to 50 μm, preferably in the range from 0.5 to 10 μm, very particularly preferably in Range from 1 to 3 µm. 17. The method according to any one of the preceding claims, characterized in that that the baked paint layer after crosslinking a layer thickness in Has a range of 5 to 1000 microns, preferably in the range of 10 to 400 µm, very particularly preferably in the range from 15 to 60 µm. 18. The method according to any one of the preceding claims, characterized in that that as the only lacquer a one-coat topcoat at high speed is applied. 19. The method according to any one of the preceding claims, characterized in that a treatment layer is formed with the pretreatment agent, which acts as a pre-treatment and primer. 20. The method according to any one of the preceding claims, characterized in that a powder for a plain unstructured coating, a powder for a  multicolored unstructured coating or / and a powder for a multicolored structured coating is used. 21. The method according to any one of the preceding claims, characterized in that the coated surface is at least partially covered by a film or Adhesive film is protected. 22. The method according to any one of the preceding claims, characterized in that the coated body may be deformed, cut - cut in particular in the longitudinal or / and in the transverse direction - and may be deformed again, such as. B. beaded, roll formed, deep-drawn or / and folded. 23. Use of the process according to claims 1 to 22 manufactured products as interior and exterior claddings, Device covers z. B. for household appliances and small electrical appliances, especially with decorated outer cladding, perforated sheets especially for Loudspeakers and soundproofing panels, room dividers, partitions, Furniture elements, shelves, vehicle and aircraft interior linings such. B. Dashboards, frames and frame constructions, facings, Lighting fixtures.