Polymeric coating mixture, method for applying this coating mixture to a metallic base for protecting an edge or a part protective layer, a base coated in this manner and the use thereof

Abstract

The invention relates to a coating mixture for applying a polymeric, corrosion-preventing protective layer to a metallic base for protecting an edge area, a soldered point, a weld seam and/or a repair point or for sealing the seam of one or more optionally interjoined strips, metal sheets and/or shaped parts. According to the invention, the coating mixture is largely or entirely free of water and/or of organic solvents, whereby it contains at least one radically polymerizable binding agent and at least one compound that forms free radicals when subjected to the action of actinic radiation. This radically polymerizable compound is largely or completely cured with the formed free radicals when subjected to actinic irradiation. The invention also relates to a coating mixture of the aforementioned type that additionally contains at least one post-crosslinking compound, whereby the radically polymerizable compound, when subjected to actinic irradiation, does not completely cure with the formed free radicals at temperatures ranging from 10 to 200° C. but additionally has reactive bonds that lead to an extensive or complete curing when brought into contact with the post-crosslinking compound(s). The invention additionally relates to a method for producing a polymeric corrosion-preventing protective coating using this coating mixture. Finally, the invention relates to a protective coating produced in the aforementioned manner or to a metallic base correspondingly coated and to the uses thereof.

1 - 47 . (canceled)  
     
     
         48 . A coating mixture largely or entirely free of water and organic solvent, comprising at least one binder which can undergo free-radical polymerization and at least one compound which forms free radicals under the action of actinic radiation, and wherein, under the actinic irradiation, the compound which can undergo free-radical polymerization is largely or completely cured with the free radicals formed, wherein the coating mixture is largely or entirely free of water and organic solvent.  
     
     
         49 . A coating mixture largely or entirely free of water and organic solvent comprising at least one binder which can undergo free-radical polymerization, at least one post-crosslinking compound and at least one compound which forms free radicals under the action of actinic radiation, and wherein, under the actinic irradiation, the compound which can undergo free-radical polymerization is not cured completely at temperatures in the range from 10 to 200° C. with the free radicals formed, but still has reactive bonds which lead to substantial or complete curing in contact with post-crosslinking compound, wherein the coating mixture is largely or entirely free of water and organic solvent.  
     
     
         50 . A coating mixture according to  claim 48  comprising a content of at least one compound which can undergo free-radical polymerization, in particular with a total content of compounds which can undergo free-radical polymerization in the range from 15 to 70 wt. %, based on the dry substance.  
     
     
         51 . A coating mixture according to  claim 49  comprising a content of at least one compound which can undergo free-radical polymerization, in particular with a total content of compounds which can undergo free-radical polymerization in the range from 15 to 70 wt. %, based on the dry substance.  
     
     
         52 . The coating mixture according to  claim 48  comprising at least one binder which renders possible post-crosslinking, the total content of the post-crosslinking compound of at least one being, in particular, 0.3 to 30 wt. %, based on the dry substance.  
     
     
         53 . The coating mixture according to  claim 49  comprising at least one binder which renders possible post-crosslinking, the total content of the post-crosslinking compound of at least one being, in particular, 0.3 to 30 wt. %, based on the dry substance.  
     
     
         54 . The coating mixture according to  claim 48 , having a content of at least one compound which forms free radicals under the action of actinic radiation, the total content of compounds which form free radicals being, in particular, in the range from 3 to 15 wt. %, based on the dry substance.  
     
     
         55 . The coating mixture according to  claim 49 , having a content of at least one compound which forms free radicals under the action of actinic radiation, the total content of compounds which form free radicals being, in particular, in the range from 3 to 15 wt. %, based on the dry substance.  
     
     
         56 . The coating mixture according to  claim 48 , containing at least one monomer, wherein the total content of the at least one monomer in the range from 1 to 60 wt. %, based on the dry substance.  
     
     
         57 . The coating mixture according to  claim 49 , containing at least one monomer, wherein the total content of the at least one monomer in the range from 1 to 60 wt. %, based on the dry substance.  
     
     
         58 . The coating mixture according to  claim 48 , containing at least one adhesion promoter, wherein the total content of the at least one adhesion promoter is in the range from 0.1 to 25 wt. %, based on the dry substance.  
     
     
         59 . The coating mixture according to  claim 49 , containing at least one adhesion promoter, wherein the total content of the at least one adhesion promoter is in the range from 0.1 to 25 wt. %, based on the dry substance.  
     
     
         60 . The coating mixture of  claim 48 , containing at least one corrosion prevention pigment, wherein the total content of said at least one corrosion prevention pigment is in the range from 0.1 to 15 wt. %, based on the dry substance.  
     
     
         61 . The coating mixture of  claim 49 , containing at least one corrosion prevention pigment, wherein the total content of said at least one corrosion prevention pigment is in the range from 0.1 to 15 wt. %, based on the dry substance.  
     
     
         62 . The coating mixture according to  claim 48 , containing at least one lubricant wherein the total content of said at least one lubricant is in the range from 0.05 to 5 wt. %, based on the dry substance.  
     
     
         63 . The coating mixture according to  claim 49 , containing at least one lubricant wherein the total content of said at least one lubricant is in the range from 0.05 to 5 wt. %, based on the dry substance.  
     
     
         64 . A coating mixture according to  claim 48  containing additives.  
     
     
         65 . The method of  claim 64 , wherein said additives are selected from the group consisting of thixotropy auxiliaries, defoamers, surface additives for increasing the scratch resistance, additives for wetting the substrate wherein the total content of such additives being, in particular, in the range from 0.05 to 10 wt. %, based on the dry substance.  
     
     
         66 . A coating mixture according to  claim 48  comprising up to 10 wt. % of water or/and a total content of organic solvent of up to 10 wt. % or/and is thixotropic.  
     
     
         67 . A coating mixture according to  claim 48  having a viscosity in the range from 1,000 to 60,000 mPa·s.  
     
     
         68 . A coated metallic substrate comprising a metallic substrate which has a surface comprising at least one of aluminium steel, an alloy comprising aluminium, iron, magnesium, titanium or zinc and the coating of  claim 48 .  
     
     
         69 . A process comprising applying the coating mixture of  claim 48  to at least a part of a surface of a metallic substrate and applying actinic radiation of such an intensity and for such a time period that a firmly adhering, ductile, corrosion-preventing coating is formed on the substrate to yield the coated substrate.  
     
     
         70 . The method of  claim 69  further comprising drying the coating.  
     
     
         71 . The process according to  claim 69 , wherein the metallic substrate has a surface substantially comprising aluminium, steel or/and an alloy comprising aluminium, iron, magnesium, titanium or/and zinc, it being possible for this surface also additionally to be provided with at least one pretreatment layer.  
     
     
         72 . The process according to  claim 69 , wherein the metallic substrate is galvanized electrolytically or hot galvanized.  
     
     
         73 . The process according to  claim 69 , wherein the metallic substrate is covered with at least one pretreatment layer, with at least one lacquer layer or at least one lacquer-like layer before the polymeric mixture is applied.  
     
     
         74 . The process according to  claim 69 , wherein the metallic substrate is coated with a polymeric covering in the region of the edge or/and the seam on each side of the edge and over the edge or along the edge and over the edge, preferably to a width of in each case 0.5 to 20 mm from the edge or seam.  
     
     
         75 . The process according to clam  69 , wherein the metallic substrate is closed and optionally at least filled to a slight degree with a more thinly liquid coating mixture in the region of the seam where there is a hollow cavity and the coating mixture has a viscosity in the range from 1,000 to 20,000 mPa·s.  
     
     
         76 . The process according to  claim 69 , wherein before application of the coating mixture an electro-dipcoating substitute is applied and optionally pretreatment is applied.  
     
     
         77 . The process according to  claim 69 , wherein said metallic substrate has at least two lacquer layers and is cut, stamped or trimmed, before the coating mixture for the polymeric covering is applied.  
     
     
         78 . The process according to  claim 69 , wherein said surface is first cut, stamped or trimmed, and thereafter alkaline cleaned or acid cleaned or pickled, and then coating is conducted with at least one pretreatment solution, before the coating mixture for the polymeric covering is applied.  
     
     
         79 . The process according to  claim 69 , wherein said metallic substrate is heated to a temperature in the range from 10 to 120° C. prior to coating with the coating mixture for the polymeric covering.  
     
     
         80 . The process according to  claim 69 , wherein said surface of the metallic substrate is covered with the coating mixture for the polymeric covering at a temperature in the range from −20 to 180° C.  
     
     
         81 . The process according to  claim 69 , wherein the surface of the metallic substrate is covered with the coating mixture for the polymeric covering by brushing on, pouring, worm application, spraying, misting, dipping or rolling.  
     
     
         82 . The process according to  claim 69 , wherein the coating mixture for the polymeric covering has a viscosity in the range from 2,000 to 50,000 mPa·s.  
     
     
         83 . The process according to  claim 69 , wherein said metallic substrate is a strip and is coated at a strip running speed in the range from 30 to 220 m per minute, it being possible for the application device of the coating mixture or/and the device for the actinic irradiation of the polymeric covering to be held in a fixed position.  
     
     
         84 . The process according to clam  69 , wherein said metallic substrate is moved with a speed in the range from 0.01 to 200 m per minute, and at least one of an application device for the coating mixture a device for the actinic irradiation of the polymeric covering are held in a fixed position.  
     
     
         85 . The process according to  claim 69 , wherein the metallic substrate is held in a fixed position, and in that an application device for the coating mixture or a device for the actinic irradiation of the polymeric covering are moved at a speed in the range from 0.01 to 200 m per minute.  
     
     
         86 . The process according to  claim 69 , wherein an application device for the coating mixture and a device for the actinic irradiation of the polymeric covering are coupled to one another.  
     
     
         87 . The process according to  claim 69 , wherein after application the polymeric covering is heated to temperatures which are higher than the temperature of the metallic substrate on application of the polymeric covering by 1 to 60° C., in order to allow the polymeric covering to flow.  
     
     
         88 . The process according to  claim 69 , wherein the polymeric covering is irradiated with actinic radiation directly after application or later.  
     
     
         89 . The process according to  claim 69 , wherein the substrate coated with the polymeric, partly cured covering is then heated to temperatures in the range from 80 to 180° C. in order to initiate the post-crosslinking reaction and to carry out thermal curing.  
     
     
         90 . The process according to  claim 69 , wherein all burrs of a cut edge of said metallic substrate are covered with the polymeric covering.  
     
     
         91 . The process according to  claim 69 , wherein covering has a layer thickness in the range from 1 to 800 μm.  
     
     
         92 . The process according to  claim 69 , wherein after application and at least partial curing of the polymeric covering, a coating of in each case at least one electro-dipcoating, electro-dipcoating substitute, lacquer or lacquer-like mixture is applied to the metallic substrate.  
     
     
         93 . The process according to  claim 69 , wherein the polymeric covering tolerates a subsequent exposure to heat of at least 140° C. without cracking.  
     
     
         94 . The process according to  claim 69 , wherein after application and at least partial curing of the polymeric coating and optionally after application of at least one further coating, an adhesive layer is applied to the metallic substrate and the metallic substrate prepared in this way is glued with at least one other element.  
     
     
         95 . The process according to  claim 69 , wherein the metallic substrate is joined to at least one other element.  
     
     
         96 . The process according to  claim 69 , wherein the polymeric covering is largely or completely cured and corrosion-resistant such that still no rust sites are detectable after 1,000 h of the salt spray test in accordance with DIN 50021.  
     
     
         97 . The process according to  claim 69 , wherein the polymeric covering is largely or completely cured and is corrosion-resistant such that still no rust sites are detectable after 10 cycles of the alternating climate test in accordance with VDA 621-415, preferably even not after 20 cycles.  
     
     
         98 . The process according to  claim 69 , wherein the polymeric covering is largely or completely cured and has an indentation resistance in accordance with DIN EN ISO 2815 at a dry film thickness of approximately 100 μm in the range from 60 to 150.  
     
     
         99 . The process according to  claim 69 , wherein the polymeric covering is largely or completely cured and the covering has an elasticity of at least 5 mm in the indentation test in accordance with DIN EN ISO 1520, preferably of at least 6 mm.  
     
     
         100 . The process according to  claim 69 , wherein at least one edge of the substrate and at least one seam of the substrate are protected simultaneously.  
     
     
         101 . A covering of a crosslinked coating mixture produced by actinic irradiation or actinic irradiation and heat treatment at temperatures of at least 80° C. of the coating mixture according to  claim 48  applied to a metallic, optionally additionally coated substrate, and optionally by prior drying.  
     
     
         102 . A covering of a crosslinked coating mixture produced by actinic irradiation or actinic irradiation and heat treatment at temperatures of at least 80° C. of the coating mixture according to  claim 49  applied to a metallic, optionally additionally coated substrate, and optionally by prior drying.  
     
     
         103 . A metallic substrate with a largely or completely cured polymeric covering produced according to the process of  claim 48 .  
     
     
         104 . A metallic substrate with a largely or completely cured polymeric covering produced according to the process of  claim 49 .  
     
     
         105 . A product of manufacture comprising the metallic substrate of  claim 101 , wherein the product of manufacture is selected from the group consisting of a vehicle, an exterior facing, a roof lining, a cabinet element and shelving, a domestic appliance, a door, a tailgate, an engine bonnet, a bumper, a piece of furniture, a garage door, a housing, a lamp, a light, a traffic light, a window, a bicycle and a radiator.