MXPA06010094A - Method for producing a multilayered film f and use thereof - Google Patents

Abstract

The invention relates to a method for producing a multilayered film F during which:a. a base lacquer layer 1a is applied to a carrier film and a remaining content of volatile substances of x is set to less than 10%by weight whereby resulting in a conditioned base lacquer layer 1b;b. the resulting composite is subjected to a temperature of lower than 50°C;c. a second pigmented base lacquer layer 2a is optionally applied to the base lacquer layer 1b, and a remaining content of volatile substances of y is set to less than 10%by weight whereby resulting in a conditioned base lacquer layer 2b;d. the optionally resulting composite is held to a temperature of lower than 50°C, and;e. a clear lacquer coat is applied to the base lacquer layer 1b or 2b, and a remaining content of volatile substances of z is set to less than 5%by weight whereby resulting in a conditioned, deformable clear lacquer layer 3b that can be cured thermally and/or by means of actinic radiation. The invention also relates to the use of the multilayered film F for producing chromophoric and/or effect-producing films.

Description

PROCESS FOR PRODUCING A MULTI LAYER LAYER AND USING THE SAME FIELD OF THE INVENTION The present invention relates to a new process for producing a multilayer sheet or sheet. The present invention also relates to the use of the sheet S produced by the new process to produce coatings of color and effect on three-dimensional substrates, especially on automobile bodies. PREVIOUS TECHNIQUE The systems of color painting and / or effect on the bodies of motor vehicles, especially automobile bodies, are now preferably composed of a plurality of coating films which are applied on top of one another and have different properties .

By way of example, a substrate will be applied thereto in succession an electrodeposited electrocoating (EC) as a primer coating, a surface coating or anti-scratch primer coating by gravel, a base coat, and a clear or transparent coating. Within this system the EC serves in particular to protect the sheet metal from corrosion. It is also frequently referred to by those skilled in the art as the primer coating.

The surface coating serves to mask the non-uniformity in the substrate and by virtue of its elasticity ensures the resistance to chips. Where appropriate, the surface coating can also serve to reinforce the power to hide and deepen the shadow of the paint system. The base coating contributes to the optical effects depending on the color and / or the angle. Both the brightness (quantity) and the color (through the specific absorption of the wavelength through the interference) of the reflected light can vary depending on the viewing angle, a phenomenon that is also referred to as the emergence of brightness and / or emergence of color. The transparent coating serves to intensify the optical effects and protect the painting system against mechanical and chemical damage. The basecoat and the clearcoat are often referred to collectively as the topcoat. For additional details refer to Ropp Lexikon Lacke und Druckfarben, Geog. Thieme Verlag, Stuttgart, New Cork, 1998, pages 49 and 51, "Automotive finishes". Multiple coating paint systems of this type that fully comply with all the requirements imposed on them are frequently also referred to by those in the art as having class A surfaces. One disadvantage is that these color and / or effect paint systems , they must be applied often in four separate stages, between each of which the applied films must evaporate and also, where appropriate, cook, a group of operations that needs three-dimensional coating lines, very complex, in each plant of automobiles, for the coating of bodies, and with the premises of each supplier, for the coating of modules and components for external assembly; that complete is very time-consuming and labor-intensive; and that leads to increased energy costs and capital costs. It has also been recognized in the art that the application conditions for the basecoating materials in particular can greatly affect the color characteristics. With respect to the applied basecoat films, the same is true for different drying conditions that must be established due to the use of different substrates, such as plastics and metals. In practice these factors need to develop measures for the color matching between the components that are connected together directly on a vehicle body.

More recently, to avoid these problems at the beginning, color films and / or multi-layer effect have been proposed for the coating of bodyworks for motor vehicles. These color films and / or multi-layer effect comprise: as is known, a sheet or carrier sheet, at least one base coat of color and / or effect, and a transparent coating. They correspond in their construction, according to the systems of color painting and / or conventional multiple coating effect. The color films and / or multi-layer effect, however, pretend to be capable of being produced under constant conditions and applied to any desired substrate to give a color and / or optical effect independent of the process and the substrate. The application takes place by metal rolling, injection molding with thermoplastics, foam back molding or compression molding. Processes and corresponding sheets are known, for example, from the US patents US 4,8109,540 A, US 4,931,324 A or US 5,114,789 A, European patents EP 0 266 109 Bl, EP 0 285 071 Bl, EP 0 352 298 Bl or EP 0 449 982 Bl, European Patent Applications EP 0 050 794 A1, EP 0 261 815 A1, EP 0 395 266 A2, EP 0 754 740 A2, or EP 0 949 120 Al, or international patent applications WO 96/40449 Al or WO 03/016095 Al. The intention of this is to make it possible to respond more effectively to the call of the automotive industry for Class A surfaces for the modules and components mounted on the outside for the production of new car models. Existing processes and existing color and / or effect films, however, are unable to fully respond to this call or requirement. Since known color and / or effect films are highly stretched when used for the coating of three-dimensional substrates, especially automobile bodies and modules and components mounted externally thereto, it is necessary that their base coatings and transparent coatings be considerably thicker than conventional base coatings and transparent coatings, to maintain the safety of an isotropic colored place, an isotropic changing tone behavior and high covering power of the base coat, and also the visual and protective functions of the transparent coating, in each one and in layer point. However, increasing the thickness of the dry film leads to a series of problems during the production and application of the known color and / or effect films, and these problems accumulate to form a considerable barrier to the production of class surfaces. A. For example, known color and / or effect films often can not be stretched to the extent that it would be necessary for the coating of three-dimensional substrates in a complex manner. If such stretching is attempted in any way, some or all of the layers may suffer mechanical damage and / or delamination. The higher dry film thicknesses that are required means that in the production of the known color and / or effect films they must be expanded to a higher level of effort in the application of the individual films and in the control of the fraction of the volatiles in it. Excessive wet film thicknesses, for example, can lead to the resulting base coat having the wrong hue. Inadequate drying can induce unwanted adhesion to the base coat. Residual solvent and / or excessive water content and / or excessively rapid removal of solvents and / or water can lead to the development in the base coat of holes and protrusions or blisters of wet film thicknesses of only 20 μm. This results in base coatings having poor technological properties, particularly with respect to adhesion, gravel resistance, resistance to condensation and to changing color and tone. Following the wet wet application of the basecoat material and the clearcoat material, there are undesired interactions between the wet films. In particular, may have sunk the transparent coating material, leading to fogging of the resulting transparent coating. The prior technique makes only selective proposals to solve individual problems; - for example, according to EP 0 395 266 Al, page 5, lines 47 to 58, the applied basecoat films are to be pre-dried at 71 to 93 ° C for from one minute to one hour. The temperature is to be chosen so that the carrier sheet or sheet is not distorted or degraded. - according to EP 0 754 740 A2, page 6, column 9, lines 7 to 11, the applied basecoat film is to be pre-dried at 60 ° C for 5 minutes. - in accordance with EP 0 266 109 A2 a self-supporting assembly of the base coating layer and the clear coating layer is to be produced, although specific drying parameters are not established.

In transparent coating films too, high wet film thicknesses can give rise to serious problems, leading to transparent coatings to have poor technological properties. In particular, they can produce an excessive fraction of volatile constituents. - surface defects on the transparent coating surface immediately after drying, which leads to a darkening of the transparent coating, - surface defects during storage of the sheet as a result of diffusion, for example, lead to wave formation in the transparent coating, and / or, - the surface defects during the final curing of the transparent coating film, leads to the formation of blisters, and can also cause problems in further processing, such as, for example, the formation of blisters during thermoforming, and excessive adhesion to the protective sheet. In the case of preliminary drying it is necessary to ensure very strictly that the drying temperature is not above the softening temperature of the carrier film and that there is no thermal crosslinking of the transparent coating film and / or that it does not form too high a molecular weight, since otherwise the exposed problems are further intensified. In this context also the prior art gives only selective proposals towards the solution of individual problems: for example, according to EP 0 395 266 Al, page 6, lines 39 to 45, the transparent coating films are going to be cured or Pre-dry at 71 to 93 ° C from one minute to one hour. The temperature is to be chosen so that the carrier sheet does not distort or degrade. - according to EP 0 754 740 A2, page 6, column 9, lines 11 to 15, the applied transparent coating films are to be evaporated at 23 ° C for 5 minutes and cured at 80 ° C for 45 minutes. - according to EP 0 266 109 A2 a self-supporting assembly of the base coating layer and the transparent coating layer will be produced, although the specific drying parameters are not established. An additional problem arises from the flow disruptions during the application of the second clearcoat film and the clearcoat film, these disruptions occur when the temperature of the conditioned coating film to which the next coating film is applied is too high. Flow defects of this type lead in particular to visual non-homogeneities in the coated sheet. Problem to which the invention is directed. It is an object of the present invention to provide a novel process for producing a multilayer S sheet by coating a carrier sheet optionally pretreated with: 1. a pigmented basecoat film, 2. if desired, a second coating film pigmented base, and 3. a transparent coating film, which does not have the disadvantages described above in the prior art but which can instead be easily and safely carried out to give - with outstanding reproducibility - sheets or sheets S of layers multiple that can be stored without problems and can be stretched without mechanical damage and / or delamination of any or all of the layers, and that, following the application of the three-dimensional substrates, by the realization of the S sheets and the injection molding, by example, and preferably a subsequent finishing cure, gives coated three-dimensional substrates, especially bodywork or modules for coated cars and components mounted on the outside for automobile bodies, having surfaces of color and / or effect of class A. It is intended in particular that the new process should allow to produce basecoat films in the high thicknesses of wet film required without this leading to an incorrect tint and / or unwanted adhesion of the resulting base coat. It is also intended that the formation of blisters in the base coat should be avoided. It is intended that this will ultimately result in base coatings that have outstanding technological properties, particularly with respect to adhesion, resistance to scratching by stones or gravel, resistance to condensation, matrix and changing tone. With the new process, following the wet wet application of the basecoat material and the clearcoating material, there should be no undesired interactions between the wet films. A particular objective is to avoid the collapse of the transparent coating material, since it would lead to the darkening of the resulting transparent coating.

With the help of the new process, it should be possible to "produce transparent coating films in the high wet film thickness without problems, leading to transparent coatings having outstanding technological properties. In particular, there should not be: - surface defects in the transparent coating surface immediately after drying, leading to darkening of the transparent coating, - surface defects during the storage of the sheet, leading to the formation of transparent coating waves, and - surface defects during the finishing curing. of the transparent coating film, leading to the formation of blisters. Additionally, there will be no additional problems associated with further processing, such as, for example, the formation of blisters during thermoforming, and excessive adhesion to the protective sheet. In addition, leveling problems arise when the second transparent coating film is applied and when the transparent coating film should be avoided. With the new process, the drying temperature should not be above the softening temperature of the carrier sheet. With the new process, in addition, there must be no thermal crosslinking of the transparent coating film and / or the development of an excessive molecular weight, so that the deformability and continuous stretchability of the multilayer S sheets is ensured. The solution provided by the invention The invention provides, accordingly, the new process for producing a multilayer sheet S by coating a carrier sheet optionally pretreated with 1. a pigmented base coat film, 2. if desired, a second pigmented base coating film, and 3. a clear coating film, which involves: a. applying a pigmented basecoating material to the carrier sheet to give a wet basecoat film, which is adjusted to the residual volatile content of x < 10% by weight, based on the base coating film to give a film Ib of conditioned base coating, b. adjusting the assembly comprising the carrier sheet and the basecoating film Ib conditioned at a temperature of < 50 ° C on the surface of the base coating film Ib, c. if desired, apply a second pigmented basecoat material, or the same pigmented basecoat material a second time, to the basecoat film Ib adjusted to the temperature and conditioned to give a wet basecoat film 2a, which adjusts to a residual content of volatiles of &< 10% by weight, based on the basecoat film, to give a conditioned basecoat film 2b, d. if appropriate, adjust the assembly comprising the carrier sheet and the basecoat films Ib and 2b conditioned at a temperature of < 50 ° C to the surface of the basecoat film 2b, e. applying a transparent coating material to the basecoat film Ib or 2b adjusted to the temperature and conditioned to give a wet transparent coating film 3a, which is adjusted to the residual volatile content of z < 5% by weight, based on the transparent coating film, to give a deformable, conditioned, clear film 3b film which is thermally curable and / or actinic radiation. The new process for producing a multi-layered sheet S is referred to below as the "process of the invention".

The invention further provides the new use of the multi-layer sheet S produced by the process of the invention to produce color and / or effect films, which serve for the coating of three-dimensional substrates, this use is referred to below as "use of according to the invention. " The advantages of the solution provided by the invention. In light of the prior artIt was surprising and not foreseeable for skilled workers that the object on which the present invention is based could be achieved by means of the process of the invention and the use according to the invention. In particular it was surprising that the process of the invention did not have the disadvantages of the previous technique but could be carried out easily and reliably and gave - with outstanding reproducibility - sheets or sheets S of multiple layers that could be stored without problems and stretching without mechanical damage and / or delamination of any or all of the layers, and which, following the application to the three-dimensional substrates, preforming the S sheets and the injection molding, for example, and preferably a subsequent finishing cure, gave three-dimensional substrates coated, especially bodywork or modules for coated cars and components mounted on the outside for automobile bodies, having color and / or class A effect surfaces. The process of the invention made it possible in particular, to produce basecoat films on the high wet film thicknesses required without this leading to an incorrect nuance or and / or unwanted adhesion to the resulting base coat. It was also possible to avoid the development of blisters in the base coat. This ultimately resulted in the base coatings having outstanding technological properties, particularly with respect to adhesion, gravel scratch resistance, condensation resistance, hue and changing tone. With the process of the invention, following wet wet application of the basecoat material and clearcoat material, there were no more undesired interactions between the wet films. In particular, it was possible to avoid the sinking of the transparent coating material and then the tarnish of the resulting transparent coating. By means of the process of the invention, it was possible to produce the transparent coating films without problems in the high thickness of wet film required, thus giving the transparent coatings having outstanding technological properties. In particular - there were no superficial defects in the transparent coating surface immediately after drying, leading to the clear coating of the coating, there were no defects during the storage of the sheet, leading to the corrugation of the transparent coating, and - there were no defects during the cure of the transparent coating film finish, leading to ampoules, furthermore, there were no further problems, such as, for example, the development of blisters during thermoforming, or excessive adhesion to the protective sheet, in the course of further processing. By means of the process of the invention, it was further possible to avoid the problems of leveling during the application of the second basecoat and during the application of the clearcoat film. With the process of the invention, it was reliably assured that the drying temperature was not above the softening temperature of the carrier sheet. Furthermore, with the new process, there was no thermal crosslinking of the transparent coating film and / or without development of excessive molecular weight, so that the deformability and stretchability of the multilayer sheets S are continuously ensured. DETAILED DESCRIPTION OF THE INVENTION The materials used in the process of the invention. For the process of the invention, it is possible to use all conventional carrier sheets, protective sheets, and adhesion coatings, such as those described in, for example, US Pat. Nos. 4,810,540 A, US 4,931,324 A or US 5,114,789 A, patents EP 0 266 109 Bl, EP 0 285 071 Bl, EP 0 352 298 Bl or EP 0 449 982 Bl, European Patent Applications EP 0 050 794 A1, EP 0 261 815 Al, EP 0 395 266 A2, EP 0 754 740 A2 or EP 0 949 120 Al, or international patent applications WO 96/40449 Al or WO 03/016095 Al. The carrier films can be pigmented or non-pigmented. Particular use is made of the carrier films described in WO 03/016095 A1, page 16, line 19 to page 17, line 3. The pigmented carrier sheets can be adapted in terms of their shade to the base coatings which will subsequently be present in them. The surface of the carrier sheets to be coated can be pretreated chemically and / or physically in a conventional manner prior to the application of the coating materials. The protective films to be applied to the carrier film / coating film composites are compatible with the transparent coating films 3b. As pigmented base coat materials for producing the films and also, where appropriate 2a, of pigmented base coat, it is possible to use all known and customary base coat materials, as described in, for example, WO 03/016095 Al, page 10, line 15, to page 14, line 22. Additional use is preferably made of aqueous basecoating materials such as those described in EP 0 754 740 and US 5,030,514 A. Different basecoating materials can be used or the same base coat for producing the films, and where appropriate 2a, of pigmented base coat. As transparent coating materials for producing the transparent coating films 3a, it is possible to use all liquid, known and customary clear coating materials which are thermally curable and / or actinic radiation, as described, for example, in WO 03/016095 A1, page 25, line 7 to page 27, line 11. It is preferred to use transparent coating materials that give a finishing cure with IV radiation and are described in, for example, DE 199 17 965 A1.

By actinic radiation is meant, here and below, electromagnetic radiation, such as near infrared (NIR), visible light, UV radiation, X-rays, and gamma radiation, especially UV radiation and corpuscular radiation, such as electron beams, alpha radiation , beta radiation, proton beams and neutron beams, especially electron beams.

METHODS AND APPARATUS USED IN CARRYING OUT THE PROCESS OF THE INVENTION For the process of the invention, it is preferred to use the apparatus that allows the continuous coating of carrier sheets or sheets similar to ribbons or bands with basecoat and clearcoat materials. The application apparatus and the carrier sheets are in relative movement relative to each other. In particular, the application apparatus is stationary and the carrier sheets are guided by passing it in continuous movement. The application apparatus can be moved transversely to and from the direction of movement of the carrier sheets. The base coating material is preferably applied by means of a directed application method. Examples of suitable directed application methods are known from WO 03/016095 A1, page 15, lines 6 to 19. Knife coverings, molding or casting apparatus and rolls are particularly used. If the pigmentation needs a certain uniformity of distribution and / or if its purpose is to adjust or fix a very specific shade and / or optical effect, then the film 2a basecoat is applied to the basecoating film Ib conditioned. In this case, the basecoating material is preferably applied by means of a non-targeted application method, which in the film 2a and, respectively, 2b of the resulting basecoat does not result in any arrangement of the pigments in a preferential direction, in other words, in the basecoat film 2a and then also in the conditioned basecoat film 2b, the pigments are in isotropic distribution. Examples of suitable non-targeted application methods and the apparatus for the same are known from WO 03/016095 A1, page 20, line 4, page 23, line 25. In particular, the pneumatic or electrostatic spray apparatus is used. , as described in WO 03/016095 Al, page 20, line 4 to page 23, line 25. So that eventually the base coat achieves the changing color and / or tone effect which is necessary for adaptation to a shade Originally defined, it is also possible that the basecoat film 2a is applied by means of high-speed electrostatic rotation or by means of electrostatically assisted pneumatic atomization. In that case the film of the base coat can be applied by means of one of the directed application methods, described above which produces an arrangement of the pigments in a preferential direction, ie an anisotropic distribution of the pigments, in the film and, respectively Ib, of the resulting base coating.

If a carrier sheet is used which corresponds substantially or entirely in its coloration to the target color of the eventual basecoat, it is possible as the film the basecoat merely to apply a color and / or effect film, without opacity, by means of pneumatic assisted atomization. electrostatically or electrostatically rotating high-speed pneumatics. The liquid transparent coating materials can be applied by means of the non-directed and directed application methods described above. Preferably the transparent coating materials are applied by directed application methods, most preferably using extrusion coaters. If liquid transparent coating materials are curable (alone or in sets) by actinic radiation they are applied and further processed in the absence of actinic radiation. For the conditioning of the films, and where appropriate 2a, of wet basecoat and also of the wet transparent coating films 2a, it is preferred to use thermal and / or convection methods, using conventional apparatuses, such as through-type ovens, radiant IR and NIR heaters, blowers, and air tunnels. The combinations of such devices are possible.

The assemblies that result in the course of the process of the invention, comprises the carrier sheet and the base lining film Ib, or the carrier sheet, the base lining film Ib, and the base lining film 2b, can be rolled up before the application of the following film, stored, transported and supplied to another application apparatus, in which they are coated with said film. For this purpose the compounds can be coated with a protective sheet, which is removed again before the film is applied. Preferably, however, the process of the invention is carried out in a continuous installation containing all of the necessary conditioning and application apparatus. Said continuous installation further comprises conventional apparatus for supplying the materials of the base coating and the transparent coating to the application apparatus; unroller for the carrier sheets and protective sheets S, and rewinders for the multilayer sheets S; the actuator apparatus for movement of the sheets and, where appropriate, the application apparatus; the suction waste apparatus for the volatiles; cooling fans and / or cooling rollers for adjusting the surface temperature of the conditioned coating films; the control and measurement apparatus; and where appropriate, the apparatus for the protection of actinic radiation. The implementation of the process of the invention Stage a of the process In stage a. of the process, a pigmented base coating material is applied to the carrier sheet to give a film the wet base coat, which is preferably adjusted by heating and / or convection to a residual volatile content of x < 10% by weight, preferably < 7% by weight, more preferably < 5% by weight, based on each case in the basecoat films, to give a film Ib of transparent coating conditioned. The application takes place under cabin conditions, such as are known from, for example, finishing in OEM production line. The wet base coating film preferably has a film thickness from 50 to 150 μm. Here and below, "volatile" are all those constituents of the basecoat materials and also of the clearcoat materials that, after the basecoat films and clearcoat films produced from the basecoat materials and the basecoat materials Clear coatings have been cured, they do not remain in the base coatings and resulting transparent coatings. Volatiles include, in particular, organic solvents and water. Prior to conditioning, preferably the basecoat film is evaporated from 1 to 6 minutes, more preferably from 2 to 4 minutes. In the course of evaporation, it is particularly preferred to adjust the temperature, humidity and velocity of the prevailing air in the area of application. If drying precedes evaporation, then drying takes place in a separate drying zone. If the conditioning of the film the base coating is preferred to employ the following drying kinetics: - in the first drying section an average drying speed of 10 to 40% weight / min is used, based on the total content of volatile of the applied basecoat film, until a residual volatile content of x = 12 to 30% by weight is reached, based on the basecoat film, and - a drying rate is employed in the last drying section. average of 1 to 6% by weight / min, based on the total volatile content of the applied basecoat film, until a residual volatile content of x < 10% by weight, more preferably < 7% by weight, in particular < 5% by weight, based on each case in the film of base coating. The conditioning of the film of the base coating is preferably carried out at temperatures from 30 to 100 ° C. Moisture is preferably adjusted from 3 to 15 g / kg. With particular preference to the conditioning period from 1 to 10 minutes. The air velocities are in particular from 0.2 to 15 m / s. The resulting conditioned base coating film Ib preferably has a film thickness from 10 to 30 μm. Stage b of the process. In stage b of the process, the resulting assembly comprising the carrier sheet and the conditioned base coating film Ib, is set at the temperature of <; 50 ° C, in particular < 35 ° C, on the surface of the film Ib of base coating. Stage c of the process. In the optional step c of the process, a second pigmented basecoating material or the same basecoating material is applied for the second time to the basecoat film Ib adjusted to the temperature and conditioned to give a wet basecoat film 2b , which is preferably adjusted by heating and / or connection to a residual content of volatiles of < 10% by weight, preferably < 7% by weight, more preferably < 5% by weight, based in each case on the base coating film, to give a film 2b of conditioned base coating. The wet base coating film 2a preferably has a film thickness from 25 to 100 μm. Prior to conditioning, the basecoat film 2a is preferably evaporated from 1 to 6 minutes, more preferably from 3 to 5 minutes. In the course of evaporation, it is particularly preferred to adjust the temperature, humidity, air velocity prevailing in the area of application. After the drying is preceded by evaporation, the drying takes place in a separate drying zone. In the conditioning of the basecoat film 2a, it is preferred to employ the following drying kinetics: - in the first drying section an average drying speed of 10 to 40% by weight / min is used, based on the total content of volatile of the applied basecoat film, until a residual volatile content of y = 12 to 30% by weight is reached, based on the basecoat film, and - in the last drying section a drying rate is employed average of 1.5 to 4% by weight / min, based on the total volatile content of the applied basecoat film, until a residual volatile content of x < 10% by weight, more preferably < 7% by weight, in particular < 5% by weight, based on each case in the basecoat film. The conditioning of the basecoat film 2a is preferably carried out at temperatures from 30 to 100 ° C. Humidity is preferably set from 3 to 15 g / kg. With particular preference the conditioning period is from 1 to 10 minutes. The air velocities are in particular from 0.2 to 15 m / s. The resulting conditioned basecoat film 2b preferably has a film thickness from 5 to 20 μm. Preferably the total film thickness of the base coat films Ib and 2b is from 15 to 50 μm. Stage d of the process. For the purposes of the process of the invention, step d of the process is carried out if there is a second base coat film 2b. In step d of the process, the resulting assembly, comprising the carrier sheet or sheets and the conditioned base coating films Ib and 2b, is set at a temperature of < 50 ° C, in particular < 35 ° C, to the surface of the base coat film 2b. Stage e of the process. In step e of the process, a base coating material is applied to the basecoat film Ib or 2b adjusted to the temperature and conditioned to give a wet transparent coating film 3a, which is adjusted by heating and / or convection to a Residual volatile content of z < 5% by weight, preferably < 3% by weight, based on the transparent coating film, to give a deformable, conditioned, clear film 3b film which is thermally curable and / or actinic radiation. The transparent coating film 3a preferably has a film thickness from 80 to 160 μm. Before conditioning the transparent coating film 3a, it preferably evaporates from 2 to 8 minutes, more preferably from 5 to 7 minutes. In the course of evaporation, it is particularly preferred to adjust the temperature, humidity and velocity of the prevailing air in the area of application. If the drying is preceded by evaporation, then drying takes place in a separate drying zone.

D In the conditioning of the transparent coating film 3a, it is preferred to employ the following drying kinetics: - in the first drying section an average drying speed of 10 to 30% by weight / min is used, based on the total content of volatiles of the applied transparent coating film, until a residual volatile content of z = 10 to 15% by weight is reached, based on the transparent coating film, and - - in the last drying section a speed is used of average drying of 0.5 to 3% by weight / min, based on the total volatile content of the applied clearcoat film, until a residual volatile content of z < 7% by weight, more preferably < 5% by weight, in particular < 3% by weight, based on each case in the transparent coating film. The transparent coating film 3a is conditioned at oven temperatures of 80 to 1 0 ° C, in particular 90 to 120 ° C. The film thickness of the conditioned transparent film 3b is preferably from 40 to 80 μm.

The step e of the process results in the multilayer sheet S and then the process of the invention is essentially concluded. However, it is possible to follow additional, appropriate process steps. Stage f of the process. In the optional step f of the process, the resultant assembly comprising the carrier sheet or sheet, the basecoating film Ib, conditioned, if appropriate, the conditioned basecoat film 2b, and the conditioned clearcoat film 3b (= foil) S multi-layer), adjusts to the temperature of < 50 ° C, in particular < 35 ° C, on the surface of the film 3b clear or transparent coating. Stage g of the process. In the optional step g of the process, the multilayer sheet S has been applied to it a conventional protective sheet. Process stage. In the optional step h of the process, the multilayer sheet S is wound to form a roll or cut into small sections. The roll can be stored and / or transported until the multi-layer sheet is further used. Use according to the invention The multilayer sheets S produced by means of the process of the invention are excellently suited for producing color and / or effect films. These films in turn are excellently suited for coating substrates, preferably three-dimensional substrates, especially car bodies and modules or external mounting components therefor. For that purpose the multi-layered S sheets are bonded to the substrates. Stretch before, during or after your union. After they have been bonded with the substrates, the multilayer sheets S are preferably converted by thermal curing and / or curing with actinic radiation in the color and / or effect films. Curing is preferably carried out as described in WO 03/016095 Al, page 27, line 19, page 28, line 24. The sheets S of the invention, after they have been preformed, retromolded by injection, and then given a finishing cure, particularly provides coated three-dimensional substrates, especially coated car bodies or modules and components mounted on the outside for automobile bodies, having surfaces of color and / or effect class A. Examples 1 to 3 The production of the sheets YES at multilayer S3 The multilayer SI sheet of Example 1 was produced using the 800 μm commercial carrier sheet with dark gray pigmentation and based on Luran® from BASF Aktiengesellschaft and also the commercially available base silver [Brillantsilber] coating material. BASF Coatings AG (with a non-volatile content of approximately 20% by weight, based on the coating material). The multilayer sheet S2 of Example 2 was produced using the commercially available 800 μm carrier sheet with light gray pigmentation and based on Luran® from BASF Aktiengesellschaft and also the commercial base [beige] coating material Travertinbeige from BASF Coatings AG (with a non-volatile content of approximately 20% by weight, based on the coating material). The multilayer sheet S3 of Example 3 was produced using the 800 μm commercial carrier sheet with black pigmentation and based on Luran® from BASF Aktiengesellschaft and also the base coating material [black] Commercial Obsidianschwarz from BASF Coatings AG (with a non-volatile content of approximately 20% by weight, based on the coating material). For Examples 1 to 3, a clear coating material was used, for example 1 of DE 199 17 965 A1 (with a non-volatile content of approximately 50% by weight, based on the coating material). The multilayer sheets SI to S3 were produced according to the following general instructions. General production instructions: The surface of the carrier sheet to be coated was subjected to a corona pretreatment at 0.5 kilowatts. The base coating material was applied to the carrier sheet using a box-type bar coater with a width of 37 cm at a belt speed of 0.5 m / min. The application was carried out with a weak air flow of 0.2 m / s, a constant temperature of 21 + 1 ° C, and a constant relative humidity of 65 + 5 ° C. The film thickness of the film of the resulting wet base coat was 100 μm. The wet base coating film was evaporated for 3 minutes under these conditions. In the first drying section, the basecoat film was dried for 3 minutes with an average drying speed of 29% by weight / min, based on the total volatile content of the applied basecoat film, until the Residual content of volatiles was x = 13% by weight, based on the base coating film.

In the last drying section, the basecoat film was dried for 3 minutes with an average drying speed of 3% by weight / min, based on the total volatile content of the applied basecoat film, until the Residual content of volatiles was x = 4% by weight, based on the basecoat film. The air temperature was 90 ° C, the humidity was 10 g / min, and the air velocities were 10 m / s. The resulting conditioned basecoat film Ib, approximately 20 μm thick, was adjusted using cooling rollers at a surface temperature < 30 ° C. The same basecoat material was applied to the basecoat film Ib adjusted to the temperature and conditioned under the following conditions, using a system for the application of pneumatic spray: speed overflow: 100ml / min; - air pressures: atomizing air: 2.5 bar; Oven air: 2.5 bar; - speed of movement of the nozzles; enough to produce superposition of the spray jet of 60%; - Nozzle / blade distance: 30 cm. The application was carried out with a weak air flow of 0.5 m / s (with the flow hitting the sheet perpendicularly), a constant temperature of 21 + 1 ° C, and a constant relative humidity of 65 + 5%. The film thickness of the resulting wet basecoat film 2a was 50 + 2 μm. The basecoat film 2a was evaporated for 3 minutes under these conditions. In the first drying section, the basecoat film 2a was dried for 3 minutes with an average drying speed of 29% by weight / min, based on the total volatile content of the applied basecoat film, until the Residual content of volatiles was y = 13% by weight, based on the basecoat film. In the last drying section, the basecoat film 2a was dried for 3 minutes with an average drying rate of 3% by weight / min, based on the total volatile content of the applied basecoat film, until the Residual content of volatiles was y = 4% by weight, based on the basecoat film. The air temperature was 90 ° C, the humidity was 10 g / min, and the air velocities were 10 m / s. The resulting conditioned basecoat film 2b, approximately 10 μm thick, was adjusted using cooling rollers at a surface temperature < 30 ° C.

The transparent coating material was applied to the basecoat film 2b adjusted to the temperature and conditioned using a box-type bar coater with a width of 37 cm. The application was carried out with a weak air flow of 0.2 m / s, a constant temperature of 21 + 1 ° C, and a constant relative humidity of 65 + 5 ° C. The thickness of the film, of the film 3a of the resulting wet transparent coating was 120 μm. It was evaporated for 6 minutes under the established conditions. In the first drying section, the transparent coating film 3a was dried for 5 minutes with an average drying speed of 17.5% by weight / min, based on the total volatile content of the applied transparent coating film, until the Residual content of volatiles was z = 12.5% by weight, based on the transparent coating film. In the last drying section, the transparent coating film 3a was dried for 10 minutes with an average drying speed of 1% by weight / min, based on the total volatile content of the applied clear coating film, until the Residual content of volatiles was z = 2.5% by weight, based on the transparent coating film.

The air temperature in the oven was 119 ° C for all drying stages. The resulting conditioned clear film 3b, 60 μm thick, was adjusted using cooling rollers at a surface temperature < 30 ° C and covered with a polypropylene protective sheet.

The resulting multilayer sheet S was wound to form a roll and stored in that form until later use. The multilayer sheets SI to S3 were able to roll up to form rollers without problems and to be stored and / or transported before their subsequent use, without detriment to their outstanding operating properties, in particular their dimensional stability on the one hand and their deformability for the other. There was no problem in cutting them into sections. It was possible to weld the sections in air tight and moisture tight films and store them in that form for months. The multilayer sheets SI to S3 were excellently suited for the production of class A surfaces in automobile bodies and for the production of modules and components mounted on the outside having class A surfaces.

Claims (20)

1. CLAIMS 1. A process for the production of a multi-layer sheet S by coating a carrier sheet optionally pretreated with: 1) a pigmented base coat film, 2) if desired, a second pigmented base coat film, and 3) a transparent or clear coating film, characterized in that a. a pigmented base coating material is applied to the carrier sheet to give a wet base coating film, which is adjusted to a residual volatile content of x < 10% by weight, based on the basecoat film, to give an Ib film of conditioned basecoat, b. the assembly comprising the carrier sheet and the conditioned base coating film Ib is set at a temperature of < 50 ° C on the surface of the base coating film Ib, c. if desired, a second pigmented basecoating material, or the same pigmented basecoat material for the second time, is applied to the basecoat film Ib adjusted to the temperature and conditioned to give a wet basecoat film 2a, which is adjusted to a residual content of volatiles of &< 10% by weight, based on the basecoat film to give a film 2b of conditioned basecoat. d. if appropriate, the assembly comprising the carrier sheet and the conditioned basecoat films Ib and 2b are set at a temperature of < 50 ° C on the surface of the basecoat film 2b, e. a transparent or clear coating material is applied to the basecoat film Ib or 2b adjusted to the temperature and conditioned to give a transparent coating film 3a, which is adjusted to a residual volatile content of z < 5% by weight, based on the transparent or clear coating film, to give a film 3b of transparent, deformable, conditioned coating, which is thermally curable and / or with actinic radiation.
2. 2. The process according to claim 1, characterized in that the residual content of volatiles in steps a), c) and / or e) is adjusted by heating and / or convection.
3. 3. The process according to claim 1 or 2, characterized in that in step a): in the first drying section, an average drying speed of 10 to 40% by weight / min is used, based on the content total volatiles of the applied basecoat film, to a residual volatile content of x = 12 to 30% by weight, based on the basecoat film, and - in the last drying section, a drying rate is employed average of 1 to 6% by weight / min, based on the total volatile content of the applied basecoat film, until a residual volatile content of x < 10% by weight, more preferably < 7% by weight, in particular < 5% by weight, based on the base coating film.
4. The process according to any of claims 1 to 3, characterized in that the base coating film Ib in step b) is adjusted to the temperature < 35 ° C on its surface.
5. The process according to any of claims 1 to 4, characterized in that in step c) in the first drying section, an average drying speed of 10 to 40% by weight / min is used, based on the total volatile content of the applied basecoat film, until a volatile residual content of y = 12 to 30% by weight is reached, based on the basecoat film, and - in the last drying section, it is employed an average drying speed of 1.5 to 4% by weight / min, based on the total volatile content of the applied basecoat film, until a residual volatile content of x < 10% by weight, more preferably < 7% by weight, in particular <; 5% by weight, based on each case in the basecoat film.
6. The process according to any of claims 1 and 5, characterized in that the basecoat film 2b in step d) is adjusted to a temperature of < 35 ° C on its surface 2b.
7. The process according to any of claims 1 to 6, characterized in that in step e) in the first drying section, an average drying speed of 10 to 30% by weight / min is used, based on the total volatile content of the applied transparent coating film, until a volatile residual content of z = 10 to 15% by weight, based on the transparent coating film, is reached, and - in the last drying section, it is employed an average drying speed of 0.5 to 3% by weight / min, based on the total volatile content of the applied clearcoat film, until a residual volatile content of z < 7% by weight, more preferably < 5% by weight, in particular < 3% by weight, based on each case in the transparent coating film.
8. 8. The process according to any of claims 1 to 7, characterized in that the assembly comprises the basecoat film Ib, if appropriate the basecoat film 2b, and the transparent coating film 3b is adjusted in a step f) at a temperature < 50 ° C on the surface of the transparent or clear coating film 3b.
9. The process according to any of claims 1 to 8, characterized in that the surface of the transparent or clear coating film 3b in a step g) is covered with a protective sheet.
10. The process according to any of claims 1 to 9, characterized in that the base coating material in step a) is applied by means of a continuous method.
11. 11. The process according to any of claims 1 to 10, characterized in that the base coating material in step c) is applied by means of a continuous method.
12. 12. The process according to any of claims 1 to 11, characterized in that the transparent coating material in step e) is applied by means of a continuous method.
13. 13. The process according to any of claims 1 to 12, characterized in that the base coating material in step a) is applied by means of a direct application method.
14. The process according to any of claims 1 to 13, characterized in that the base coating material in step c) is applied by means of a non-direct application method.
15. 15. The process according to any of claims 1 to 14, characterized in that the free side of the carrier film has been covered with an adhesion coating.
16. 16. The use of the multilayer S sheets produced by the process as claimed in any of claims 1 to 15, for the production of color and / or effect films.
17. 17. The use as claimed in claim 16, characterized in that the colored and / or effect films serve for the coating of substrates.
18. The use as claimed in claims 16 or 17, characterized in that after they have been bound with the substrates, the multilayer sheets S are converted by thermal curing and / or curing with actinic radiation in color coatings and / or effect.
19. 19. The use as claimed in claim 18, characterized in that the multilayer sheets S are stretched before, during or after their attachment to the substrates.
20. 20. The use as claimed in any of claims 17 to 19, characterized in that the substrates are bodies and modules of automobiles and components mounted on the outside for them.