Process for producing a repair coating on a coated metallic surface

Abstract

A process for producing a repair coating on at least one metallic surface that is coated with at least one corrosion protecting coating A applied with at least one composition selected from the group of pretreatment compositions, of organic compositions and of silicon compound(s) containing compositions, whereby the at least one corrosion protecting coating A has been at least partially removed in the area Z, whereby a thin corrosion protecting coating B containing at least one silicon compound is applied with a solution or dispersion containing at least one silane, at least one silanol, at least one siloxane, at least one polysiloxane or any mixture of these (=“siloxane composition”) on at least a part of the area Z. Optionally, a further corrosion protecting coating C may be applied on the thin corrosion protecting coating B generated with the siloxane composition whereby the at least one further corrosion protecting coating C is generated with at least one organic composition like a primer, a wet-primer, an e-coat, a powder coat, a base-coat or a clear-coat or with at least one composition which is the same or another siloxane composition as for the thin film B.

1 . A process for producing a repair coating on at least one metallic surface that is coated with at least one corrosion protecting coating A applied with at least one composition selected from the group of 
 A1) pretreatment compositions like activating compositions, passivating compositions, phosphating compositions, titanium compound(s) or zirconium compound(s) or both of them containing compositions and after-rinse-compositions,    A2) organic compositions like primers, wet-primers, welding primers, e-coats, powder coats, base-coats and clear-coats and of    A3) silicon compound(s) containing compositions that are solutions or dispersions containing at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes and,    whereby the at least one corrosion protecting coating A has been at least partially removed in the area Z,    whereby a thin corrosion protecting coating B containing at least one silicon compound is applied with a solution or dispersion (=“siloxane composition”) containing at least one silane, at least one silanol, at least one siloxane, at least one polysiloxane or any mixture of these on at least a part of the area Z.    
     
     
         2 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied which is without particles, fibres, pieces of fluff and other materials generating flaws having a diameter or thickness of no more than 10 μm.  
     
     
         3 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied which has a wet film thickness in the range from 0.005 to 40 μm.  
     
     
         4 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied which has a dry film thickness in the range from 0.001 to 3 μm.  
     
     
         5 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied and the thin film is then dried, e.g. at a temperature in the range from 5 to 300° C.  
     
     
         6 . The process according to  claim 1 , whereby a thin film B is applied with the siloxane composition and dried by self-drying e.g. at room temperature, by heating the coated metallic substrate, by heating with hot air, by blowing or heating with a hot gas stream or by any combination of these.  
     
     
         7 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied by contacting a tool that contains and dispenses the siloxane composition.  
     
     
         8 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied by spraying the siloxane composition e.g. with a spray can.  
     
     
         9 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied by using a tool that has a storage chamber for the siloxane composition.  
     
     
         10 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied by using a tool like a brush, like a sponge, like a tampon, like a stick or like a gel-pack.  
     
     
         11 . The process according to  claim 1 , whereby a thin film B of the siloxane composition is applied by using a tool with a storage chamber having a membrane or another porous material with the ability to transmit the siloxane composition from the storage chamber to the working surface of the tool.  
     
     
         12 . The process according to  claim 1 , whereby the siloxane composition has a viscosity in the range from 1 to 250 mPa·s measured at 20° C.  
     
     
         13 . The process according to  claim 1 , whereby the siloxane composition is a paste.  
     
     
         14 . The process according to  claim 1 , whereby the siloxane composition is applied to at least one metallic surface of iron, steel, zinc-coated or zinc-alloy-coated steel, aluminium, aluminium alloy, magnesium alloy, titanium, titanium alloy or to any mixture of these.  
     
     
         15 . The process according to  claim 1 , whereby the siloxane composition is applied to at least one surface of at least one part showing at least two different materials at its surface(s), being made of at least one metallic material, of at least one plastics material like a foil, multilayer, sheet or component of plastics material, of at least one glass material, of at least one ceramic material, of at least one wooden material or of any mixture of these.  
     
     
         16 . The process according to  claim 1 , whereby the siloxane composition is applied to at least one metallic surface of at least one sheet, to at least one complex formed part, to at least one massive part or any mixture of these.  
     
     
         17 . The process according to  claim 1 , whereby the siloxane composition is applied to at least one metallic surface of a coil, of metallic sheet, of a car body, of parts of a car, of a body of an aerospace, of a ship, of offshore-equipment, of a railcar or of any parts of them, of parts or composed parts for construction, furniture, devices or equipment—either during production or after damage or after long-term use.  
     
     
         18 . The process according to  claim 1 , whereby the at least one corrosion protecting coating A has been removed at least partially in the area Z by grinding, sanding, sandblasting or paint stripping or any combination of them.  
     
     
         19 . The process according to  claim 1 , whereby at least one corrosion protecting coating C is applied upon the thin film B whereby the coating C is generated with an organic composition like a primer, a wet-primer, an e-coat, a powder coat, a base-coat or a clear-coat or with a coating with the same or with another siloxane composition as for the thin film B or with a succession of applications of such compositions, whereby at least one coating C may optionally be applied on a great portion or on the total surface of the coated metallic part.  
     
     
         20 . The process according to  claim 1 , whereby the siloxane composition for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain at least one silicon compound selected from the group of silanes, silanols, siloxanes and polysiloxanes.  
     
     
         21 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain a content of at least one partially hydrolysed silane, of at least one totally hydrolysed silane, of at least one oligomeric siloxane, of at least one polymeric siloxane, of at least one polysiloxane or of any mixture of these.  
     
     
         22 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain a content of at least one organosilicon compound having at least one group e.g. selected from amino groups, epoxy groups, glycidoxy groups, hydroxy groups, isocyanato groups, mercapto groups, (meth)acrylato groups, (poly)sulfur groups, thiol groups, ureido groups, vinyl groups and vinylbenzene groups and at least one multifunctional silicon compound having at least two silyl groups per molecule.  
     
     
         23 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes as well as a content of at least one organic compound that is an organic monomer, an organic oligomer, an organic polymer, an organic copolymer an organic blockcopolymer or any mixture of these.  
     
     
         24 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain at least one silicon compound selected from silanes, siloxanes and polysiloxanes as well as a content of at least one acid like acetic acid, glacial acetic acid, another carbonic acid, sulphuric acid, hydrochloric acid, nitric acid, fluoric acid, any phosphorus containing acid or any mixture of these.  
     
     
         25 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain at least one silicon compound selected from silanes, siloxanes and polysiloxanes as well as a content of at least one organic solvent like an alcohol like methanol, ethanol, propanol or any mixture of these.  
     
     
         26 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes as well as a content of at least one compound containing titanium, hafnium, zirconium, aluminium or boron or even any mixture of these.  
     
     
         27 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes as well as a content of at least one additive selected from the group of particles with a grain size below one micron, surfactants, dyes, fluorescing agents, biocides, pH adjusting agents, chelates, crosslinkers suitable for chemical crosslinking upon thermal influence, photoinitiators and substances for the generation of a gel.  
     
     
         28 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B or C are solutions or dispersions that contain at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes as well as a content of at least one nitrogen containing agent like nitrate, nitrite or a guanidine compound.  
     
     
         29 . The process according to  claim 1 , whereby the siloxane compositions for the generation of the corrosion protecting coating(s) A, B, C or any combination of them are solutions or dispersions that contain at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes that has at least one functional group selected from the group consisting of amino, epoxy, glycidoxy, isocyanato, mercapto, (meth)acrylato, (poly)sulfur, ureido, vinyl and vinylbenzene.  
     
     
         30 . A tool suitable for applying a process according to  claim 1 , whereby the tool contains and dispenses a composition which is a solution or dispersion containing at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes.  
     
     
         31 . A tool suitable for applying a process according to  claim 1 , whereby the tool is a spray can, a spray instrument or a stick having a storage chamber containing a composition which is a solution or dispersion containing at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes.  
     
     
         32 . A tool suitable for applying a process according to  claim 1 , whereby the tool contains a paste which is a composition containing at least one silicon compound selected from silanes, silanols, siloxanes and polysiloxanes and whereby the tool transmits or relieves a portion of the paste when it is brought into contact with the surface to be coated.