EP3811051A1

EP3811051A1 - Method for determining the droplet size distribution during atomization and screening method based thereon in paint development

Info

Publication number: EP3811051A1
Application number: EP19732660.6A
Authority: EP
Inventors: Georg Wigger; Daniel Briesenick; Dirk EIERHOFF; Christian Bornemann; Siegfried RIEDIGER; Lutz GOEDEKE; Peter Ehrhard
Original assignee: BASF Coatings GmbH
Current assignee: BASF Coatings GmbH
Priority date: 2018-06-25
Filing date: 2019-06-24
Publication date: 2021-04-28
Also published as: US20210262911A1; JP7254839B2; CN112513611A; JP2021529656A; MX2020014310A; WO2020002245A1

Abstract

The invention relates to a method for determining the droplet size distribution within a spray and/or the homogeneity of said spray, the spray being formed when a coating agent composition is atomized, the method comprising at least steps (1) to (3), namely atomizing the coating agent composition by means of an atomizer, a spray being formed by means of the atomization, optically sensing the droplets of the formed spray by means of a traversing optical measurement (2), and determining at least one characteristic of the droplet size distribution within the spray and/or the homogeneity of the spray on the basis of optical data obtained in accordance with step (2). The invention further relates to a method for creating an electronic database and for screening coating agent compositions in the development of paint formulations, which are performed on the basis of the aforementioned method.

Description

Method for determining the droplet size distribution during atomization and a screening method based on it during the

paint development

The present invention relates to a method for determining the drop size distribution within a spray and / or the homogeneity of this spray, the spray being formed when atomizing a coating composition, which comprises at least steps (1) to (3), namely atomizing the coating composition by means of an atomizer, whereby a spray is formed by the atomization, optical detection of the drops of the spray formed by a traversing optical measurement (2) and determination of at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray based on the step (2) optical data obtained, and methods for creating an electronic database and for screening coating compositions during the development of coating formulations, which are carried out on the basis of the aforementioned method.

State of the art

In the automotive industry in particular, a number of coating compositions, such as, for example, basecoats, are often applied to the substrate to be coated using rotary atomization. Such atomizers have a rapidly rotating application body, for example a bell plate, which atomizes the coating composition to be applied, in particular in the form of drops, into a spray mist, in particular due to the centrifugal force which acts, with the formation of filaments. The coating composition is usually applied electrostatically in order to ensure the highest possible application efficiency and the lowest possible overspray. At the edge of the bell plate, the paint atomized by centrifugal forces in particular is charged by directly applying a high voltage to the coating composition to be applied (direct charging). Alternatively, instead of rotary atomizers, pneumatic atomizers can be used, by means of which the coating composition used is atomized directly in the form of drops without filaments being formed beforehand. After the respective coating composition has been applied to the substrate, the resulting film is cured or baked, optionally after additional coating compositions above it have been applied in the form of further films, in order to obtain the resulting desired coating.

Optimizing coatings obtained in this way with regard to certain desired properties of the coating, such as avoiding or at least reducing the tendency to form or occur optical defects and / or surface defects such as, for example, pinpricks, cloudiness and / or the flow properties, is comparatively complex and usually only empirically possible. This means that corresponding coating compositions or usually entire test series thereof, within which various parameters have been varied, must first be produced and then applied to a substrate and hardened or baked, as described in the preceding paragraph. The rows of coatings then obtained must then be examined for the desired properties in order to be able to assess a possible improvement in the properties examined. This procedure usually has to be repeated several times, with further parameter variation, until the desired improvement in the investigated property (s) of the coating has been achieved after curing or baking.

It is known in the prior art to investigate and characterize the coating compositions used to produce such coatings based on their shear viscosity behavior (shear rheology) in order to better understand their respective application behavior. For example, capillary rheometers can be used here. However, a disadvantage of this procedure, which focuses on the investigation of shear rheology, is that the influence of the expansion viscosity, which is quite significant during atomization, is not taken into account or is not taken into account to a sufficient extent (Extensional rheology). The stretch viscosity is a measure of the resistance of a material to flowing in a stretch flow. Such expansion flows usually occur in all relevant technical processes in addition to the shear flows, such as in the case of capillary inlet and capillary outlet flows. In the case of Newtonian flow behavior, the expansion viscosity can be calculated from its constant ratio to the classically determined shear viscosity (T routon ratio). In the case of non-Newtonian flow behavior, which occurs much more frequently in practice in a large number of applications, it is usually necessary to experimentally determine the expansion viscosity as a parameter that is independent of the shear viscosity with the aid of an expansion rheometer, if the expansion rheology in the case of the aforementioned Adequate description and characterization should be taken into account. In particular when carrying out the abovementioned atomization processes, the expansion viscosity can have a very significant influence on the atomization process and the disintegration into drops, which then form the spray mist. Methods for determining the expansion viscosity are known in the prior art. The expansion viscosity is usually determined using a Capillarv Breakup Extensional Rheometer (CaBER). So far, however, no method is available in which - without actually subjecting the material to be atomized to atomization - both tensile and shear forces are equally taken into account.

There is therefore a need for a method which makes it possible, by examining the atomization behavior of coating composition, to improve certain desired properties of the coatings to be produced by means of this atomization, such as avoiding or at least reducing the tendency to form or the occurrence of optical defects and / or to achieve surface defects without having to go through the entire painting and stoving process that is usually required to produce such coatings. Likewise, such a method should not only take sufficient account of the shear rheology that occurs, but also the expansion rheology. task

It is therefore an object of the present invention to provide a method which makes it possible to investigate and, in particular, to improve certain desired properties of coatings to be produced by atomization, such as avoiding or at least reducing the tendency to form or occur to achieve optical defects and / or surface defects without the coating composition to be used in each case being applied to a substrate by means of a conventional painting process, and in particular the resultant film having to be cured or stoved in order to produce the coating, since this is comparatively complex and at least from is disadvantageous for economic reasons. Likewise, such a method should take sufficient account of the expansion behavior that occurs during atomization. In particular, it is an object of the present invention to provide such a method for aqueous basecoats as coating compositions.

solution

This object is achieved by the subjects claimed in the patent claims and the preferred embodiments of these subjects described in the following description.

A first object of the present invention is a method for determining the drop size distribution within a spray and / or the homogeneity of this spray, the spray being carried out when atomization is carried out

Coating composition is formed, which comprises at least steps (1) to (3), namely

(1) atomizing the coating composition by means of an atomizer, a spray being formed by the atomization, (2) optical detection of the drops of the spray formed by atomization according to step (1) through a traversing optical measurement through the entire spray, the optical detection according to step (2) preferably traversing in the radial-axial direction in relation to the tilted atomizer used takes place at a tilt angle of 0 ° to 90 °, and

(3) Determination of at least one parameter of the droplet size distribution within the spray and / or the homogeneity of the spray on the basis of optical data obtained by the optical detection according to step (2), the homogeneity of the spray being the ratio of two quotients Tn / Ti _otaii and Tt2GTtoM2 to each other as a measure of the local distribution of transparent and non-transparent drops at two different positions within the spray, where Tu is the number of transparent drops in the first position 1, TT2 the number of transparent drops in the second position 2, T _TO MI corresponds to the number of all drops in the spray and thus the sum of transparent drops and non-transparent drops at position 1 and T _To tai2 corresponds to the number of all drops of the spray and thus the sum of transparent drops and non-transparent drops at position 2, whereby Position 1 is closer to the center of the spray than position 2.

The determination according to the invention of the droplet size distribution of the droplets formed by the atomization according to step (1) includes the determination of at least one parameter known to the person skilled in the art, such as a suitable mean diameter of the droplets such as, in particular, D-io value (arithmetic diameter; “1.0” moment) ), D ₃₀ value (volume-equivalent mean diameter; "3.0" - moment), Da2 value (Sauter diameter (SMD); "3.2" - moment), d _{N 5} o _% value (number referred median value) and / or dv _, 50 _% value (volume-related median value). The determination of the drop size distribution includes the determination of at least one such parameter, in particular a determination of the D-io value of the drops. The above-mentioned parameters are each the corresponding number average of the drop size distribution. The moments of the distributions are here with the capital letter "D" marked, the index determines the corresponding moment. The parameters marked with the lower case letter “d” are the percentiles (10%, 50%, 90%) of the corresponding sum curve of the distribution, whereby the 50% percentile corresponds exactly to the median value. The index "N" refers to the number-based distribution, the index "V" to the volume-based distribution.

It has surprisingly been found that the method according to the invention makes it possible to investigate and characterize the atomization behavior of a wide variety of coating compositions, in particular aqueous basecoats. This is surprisingly achieved on the basis of the drop size distribution within a spray and / or the homogeneity of this spray, the spray being formed when atomizing a coating composition, in particular due to the traversing optical measurement throughout the spray while the step (2) is being carried out. This traversing optical measurement enables in particular a (free) selection of the traversing axis and / or a (free) selection of the traversing speed when carrying out step (2) of the method according to the invention and has the advantage over conventional raster-resolved point measurements that not only drop size distribution and / or homogeneity can be recorded holistically, but the measurement can also be carried out in a much shorter time (factor 5 to 25 compared to conventional raster-resolved point measurements). In addition, the material consumption is significantly lower and the process is therefore more economical overall, since it is no longer necessary to carry out a large number of individual measurements (the finer the grid, the more punctual measurements are required for grid-resolved punctiform measurements).

The at least one parameter of the drop size distribution within the spray and / or the particular homogeneity of the spray determined by means of the method according to the invention can be incorporated in an electronic database or a corresponding database can be created and / or updated. A second object of the present invention is therefore a method for creating and / or updating an electronic database comprising at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray of atomized and different coating composition, the method comprising at least steps (1) to (3), (4A) and (5A), namely

Steps (1), (2) and (3) according to the method according to the invention for determining at least one parameter of the drop size distribution within a spray and / or the homogeneity of this spray for a first coating composition (i),

(4A) incorporation of the at least one characteristic of the drop size distribution within the spray and / or the determined homogeneity of the spray into an electronic database, determined for step (3) for the first coating composition (i), and

(5A) at least a simple repetition of steps (1) to (3) and (4A) for at least one further coating composition different from the first coating composition (i).

Preferably, the incorporation of the parameter of the drop size distribution within the spray and / or the homogeneity into the database according to step (4A) also includes the incorporation of the respective standard deviations of these determined parameters into the database.

When carrying out the method according to the invention, the influence of the expansion viscosity which occurs when atomizing coating composition compositions which can be replaced to produce coatings is taken into account to a sufficient extent. This is achieved in particular since comparatively high expansion rates are taken into account when carrying out the method according to the invention, namely expansion rates of up to 100,000 s ¹ , and thus higher expansion rates than in conventional CaBER measurements for determining the expansion viscosity, in which, in particular in the case of basecoats, only expansion rates of up to 1,000 s ¹ can be achieved, and therefore the determination of at least one parameter of the drop size distribution and / or the homogeneity in the aforementioned comparatively high strain rates occur. In contrast to conventional CaBER methods, the methods according to the invention therefore take sufficient account of the expansion viscosity and the expansion rates that occur. The fact that the method according to the invention with step (1) itself involves performing an atomization makes it possible to sufficiently consider both shear rheology and expansion rheology within a single procedure and not using methods that only use individual elements (shear rheology or expansion rheology). can capture. In particular, it was surprisingly found that by means of the method according to the invention, in particular in the case of aqueous basecoats used as coating compositions for atomization, conclusions can be drawn from the particle size distributions of the drops, i.e. the determined drop size distribution, in particular based on determinations of the D ₁₀ values as a parameter of the drops , and / or the homogeneity of the spray can be drawn to the appearance of the coating to be produced. Smaller drop sizes mean "finer" atomization of the coating composition used. Atomization as fine as possible is desirable since this is accompanied by a lower degree of wetness, that is to say a less wet appearance of the film formed after application of the coating composition used. It is known to the person skilled in the art that an excessively high degree of wetness can lead to an undesirable occurrence of stoves and / or pinpricks, to a poorer color tone and / or flop and / or to the appearance of cloudy conditions. Likewise, corresponding conclusions based on the ratio of the quotient Tn / Tr _ota n to the quotient T _T2 / T _T0 ta) _{2 can be used} as a measure of the local distribution of transparent and non-transparent drops and thus as a measure of the homogeneity of the Atomization of the resulting spray. In a spray formed during atomization, such as a rotary atomization, the proportion of non-transparent drops, for example the proportion, increases

(Effect) pigment-containing drops, due to the centrifugal force from the inside out. If the ratio of the quotient T _T1 / T _Totaii to the quotient Tt ₂ / Tto ΐ3ΐ2 _changes comparatively strongly within the spray with increasing distance from the bell _edge (if a rotary atomizer is used in step (1)), so mean! this means that the composition of the spray changes significantly from the inside to the outside. On the basis of the determination of the ratio of the quotient Tn / tiotan to the quotient T _T2 / T _To t _ai2 or on the basis of how strongly this changes from the inside out, it can thus be determined whether a material used with increasing values of the aforementioned ratio is separated more strongly during application into areas with different concentrations of (effect) pigments and is therefore more inhomogeneous or more susceptible to the formation of surface defects such as stripes than another material.

Surprisingly, by carrying out the method according to the invention, an examination and in particular an improvement of certain desired properties of coatings to be produced by means of atomization can be achieved on the basis of at least one parameter of the determined droplet size distribution and / or the homogeneity, in particular with regard to avoiding or at least reducing the tendency to Formation or occurrence of optical defects and / or surface defects without the coating composition to be used in each case using a conventional one

Painting process applied to a substrate and curing or baking of the resulting film must be carried out to produce the coating.

The present invention therefore furthermore relates to a method for screening coating compositions in the development of coating formulations, which comprises at least steps (1) to (3), (4B), (5B) and (6B) and optionally (7B), wherein at least one parameter of the droplet size distribution within the spray and / or the homogeneity of this spray is first determined in steps (1) to (3) according to the inventive method described above for determining the droplet size distribution within a spray and / or the homogeneity of this spray , These steps (1) to (3) thus correspond to steps (1) to (3) of the first object of the present invention. The method for screening coating compositions in the development of coating formulations comprises at least steps (1) to (3), (4B), (5B) and (6B) and optionally (7B), namely

(1) atomizing a coating composition (X1) by means of an atomizer, a spray being formed by the atomization,

(2) optical detection of the drops of the spray formed by atomization according to step (1) by a traversing optical measurement through the entire spray and

(3) Determination of at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray on the basis of optical data obtained by the optical detection according to step (2), the homogeneity of the spray being the ratio of two quotients Tn / Ti _o 'and Tt Tto ^ corresponds to each other as a measure of the local distribution of transparent and non-transparent drops at two different positions within the spray, where Tn the number of transparent drops at the first position 1, TT2 the number of transparent drops at the second position 2, T _To tan the number of all drops in the spray and thus the sum of transparent drops and non-transparent drops at position 1 and T _To tai2 the number of all drops of the spray and thus the sum of transparent drops and non-transparent drops at position 2 , where position 1 is closer to the center of the spray than position 2,

(4B) Comparison of the at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray determined according to step (3) for the coating composition (X1) with parameters of the drop size distribution within the spray and / or the homogeneity of the spray stored in an electronic database Sprays of further coating compositions, this database using the aforementioned method according to the invention Creating and / or updating an electronic database is available (second object of the present invention),

(5B) Check on the basis of the comparison according to step (4B) whether the at least one parameter of the droplet size distribution within the spray and / or the homogeneity of the spray determined according to step (3) for the coating composition (X1) fulfills the condition that it is less than at least one parameter stored in the database of the droplet size distribution within the spray and / or the homogeneity of the spray of a coating composition (X2) which is different from the coating composition (X1), but has an identical pigment content to the coating composition (X1) or has such a pigment content which deviates by a maximum of ± 10% by weight from the pigment content of the coating composition (X1), based on the amount of pigment present in the coating composition (X1), and which also the or the identical pigment (s) or that or the essentially contains identical pigment (s) as the coating composition (X1),

(6B) Selection of the coating composition (X1) for application to a substrate if the at least one parameter of the droplet size distribution within the spray and / or the particular homogeneity of the spray determined for the coating composition (X1) meets the condition specified in step (5B) or

Adjusting at least one parameter within the recipe of the coating composition (X1) and / or at least one process parameter when performing steps (1) to (3) of the method for screening coating composition, if the at least one parameter determined for the coating composition (X1) Droplet size distribution within the spray and / or the determined homogeneity of the spray does not meet the condition specified in step (5B),

(7B) at least one simple repetition of steps (1) to (3), (4B) and (5B), if at least one parameter adjustment was required in accordance with step (6B), until step (6B) was carried out at least once more to meet the condition in step (5B) according to step (8B), the coating composition used is selected for application to a substrate.

It has surprisingly been found that the method according to the invention for screening coating compositions in developing coating formulations is less complex than conventional methods and thus has (time) economic and economic advantages over corresponding conventional methods. By means of the method according to the invention, it can be surprisingly estimated on the basis of the determined drop size distribution and / or the homogeneity with a sufficiently high probability whether certain optical defects and / or surface defects of the coating to be produced can be expected without producing the coating at all, especially in the case of aqueous ones basecoats. Surprisingly, this is achieved by determining the drop size distribution and / or the homogeneity of the drops occurring during atomization, which form the spray mist, and by correlating these determined parameters with the occurrence of the aforementioned optical defects and / or surface defects or their avoidance / reduction depending on of this particle size distribution occurring during atomization and / or the homogeneity of the drops, it is possible to determine the resulting properties such as optical properties and / or

To be able to control surface properties of the coating to be produced and in particular the occurrence of optical defects and / or

Avoid or at least reduce surface defects. In other words, by means of the method according to the invention, predictions regarding the qualitative properties of the final can be made on the basis of the investigation of the atomization behavior of a coating composition Coating (such as the appearance of pinholes, cloudiness, streakiness, course or appearance). In particular, it was surprisingly found that these correlate better with these properties than other methods known from the prior art. The method according to the invention thus enables a simple and efficient method for quality assurance and enables a targeted development of coating composition without having to resort to comparatively complex coating methods for (model) substrates. In particular, the step of hardening or baking can be omitted.

Detailed description

Method according to the invention for determining the drop size distribution and / or the homogeneity

A first subject of the present invention is a method for determining the drop size distribution within a spray and / or the homogeneity of this spray, the spray being formed when atomizing a coating composition, which comprises at least steps (1) to (3)

The atomization is preferably carried out using a rotary atomizer or a pneumatic atomizer.

The term “rotary atomization” or “high-speed rotary atomization” or “high-speed rotary atomization” is known to the person skilled in the art. Such rotary atomizers have a rotating application body which, due to the acting centrifugal force, atomizes the coating composition to be applied into a spray in the form of drops. The application body is a preferably metallic bell cup.

In the case of rotary atomization by means of atomizers, so-called filaments are first formed on the edge of the bell plate, which then further decompose into the aforementioned drops in the course of the atomization process, which then form a drop Form spray mist. The filaments thus represent a preliminary stage of these drops. The filaments can be described and characterized by their filament length (also referred to as “thread length”) and their diameter (also referred to as “thread diameter”).

The term “pneumatic atomization” and pneumatic atomizers used for this purpose are also known to the person skilled in the art.

When carrying out the method according to the invention, the expansion viscosity occurring during atomization is taken into account to a sufficient extent. The person skilled in the art is familiar with the concept of the expansion viscosity with the unit of Pascal second (Pa s) as a measure of the resistance of a material to the flow in an expansion flow. Methods for determining the expansion viscosity are also known to the person skilled in the art. The expansion viscosity is usually measured using a so-called capillary breakup extensiona! Determines rheometer (CaBER), which are sold, for example, by Thermo Scientific.

Step 1)

Step (1) of the method according to the invention relates to atomization of the coating composition by means of an atomizer, a spray being formed by the atomization. As mentioned above, the atomizer is preferably a rotary atomizer or a pneumatic atomizer. If a rotary atomizer is used, it preferably has a bell cup capable of rotation as the application body. The atomized coating composition can optionally be electrostatically charged at the edge of the bell cup by applying a voltage. However, this is not necessary for the implementation of the method according to the invention, in particular for the implementation of step (1) of the method according to the invention.

If a rotary atomizer is used in step (1), the rotational speed (rotational speed) of the bell cup can be adjusted. In the present case, the rotational speed is preferably at least 10,000 Revolutions / min (rpm) and at a maximum of 70,000 revolutions / min. The rotational speed is preferably in a range from 15,000 to 70,000 rpm, particularly preferably in a range from 17,000 to 70,000 rpm, in particular from 18,000 to 65,000 rpm or from 18,000 to 60,000 rpm. From a rotational speed of 15,000 revolutions per minute, a corresponding rotary atomizer in the sense of this invention is preferably referred to as a high-speed rotary atomizer. Rotary atomization in general and high speed rotary atomization in particular are widely used in the automotive industry. The (high-speed) rotary atomizers used for this purpose are commercially available, for example products from the Dürr EcobeIl® series. Such atomizers are preferably suitable for the electrostatic application of a large number of different coating compositions, such as paints, which are used in the automotive industry. Basecoats, in particular aqueous basecoats, are particularly preferably used as coating compositions in the process according to the invention. The coating composition can be applied electrostatically, but need not. In the case of electrostatic application, the coating composition atomized by centrifugal forces is electrostatically charged at the edge of the bell plate by preferably directly applying a voltage, such as high voltage, to the coating composition to be applied {direct charging).

The outflow rate of the coating composition to be atomized during the implementation of step (1) is adjustable. The outflow rate of the coating composition to be atomized during step (1) is preferably in a range from 50 to 1,000 ml / min, particularly preferably in a range from 100 to 800 ml / min, very particularly preferably in a range from 150 to 600 ml / min, especially in a range from 200 to 550 ml / min.

Preferably, the outflow rate of the coating composition to be atomized during the implementation of step (1) is in a range from 100 to 1,000 ml / min or from 200 to 550 ml / min and the speed of the Bell plates in the case of rotary atomization in a range from 15,000 to 70,000 revolutions / min or from 15,000 to 60,000 rpm.

In step (1) of the process according to the invention, a basecoat, particularly preferably an aqueous basecoat, is preferably used as the coating composition, in particular an aqueous basecoat which contains at least one effect pigment.

Step 2)

In step (2) of the method according to the invention, the drops of the spray formed by atomization according to step (1) are optically detected by a traversing optical measurement through the entire spray.

Carrying out this traversing measurement enables a holistic recording of the entire spray and thus of the entire spectrum of drops forming the spray. This makes it possible to record all the droplet sizes forming the spray. The entire spray can be measured holistically (and not just individual areas of the spray). The traversing measurement allows the drops to be measured optically, i.e. point-specific, in many places in the spray of atomization), whereby a more precise determination is made in the following step (3) than if the measurement is not traversing. The traversing measurement is preferably carried out by moving the atomizing head of the atomizer used while carrying out step (2). Alternatively, however, a relative movement of the measuring system is also possible.

The traversing optical measurement according to step (2) can be carried out at different traversing speeds. This speed can be linear or non-linear. The area weighting can be simplified by selecting the traversing speed: an increase in traversing speed with increasing area segments fulfills this purpose, so that the product of area and dwell time is constant. The traversing speed is preferably selected such that at least 10,000 counts per Area segment of the spray can be obtained. In this context, the term “counts” denotes the number of drops detected during the measurement within the spray or different surface segments of the spray. The surface segments represent positions within the spray.

The optical detection according to step (2) of the method according to the invention is preferably carried out by an optical measurement which is based on scattered light tests on the drops contained in the spray and is carried out on them. This measurement is preferably carried out using at least one laser.

The optical detection according to step (2) of the method according to the invention is preferably carried out by means of phase Doppler anemometry (PDA) and / or by means of time-shift measurement technology (TS). At least one characteristic of the drop size distribution can be determined in step (3) from the optical data obtained using PDA when step (2) is carried out. In step (3), at least one parameter of the droplet size distribution and the homogeneity of the spray can be determined from the optical data obtained by means of TS when step (2) is carried out.

The optical measurement is preferably carried out on a measurement axis which is traversed repeatedly, as shown for example in FIG. 1. The repetition is preferably 1 to 5 times, particularly preferably it is carried out at least 5 times. The measurement is particularly preferably carried out with at least 10,000 counts per measurement and / or at least 10,000 counts per surface segment within the spray. A double measurement of the individual events is preferably prevented by an internal evaluation. 1, a rotary atomizer is used as an example.

Step (2) can be carried out at different tilt angles of the atomizer relative to the measuring device by means of which the measurement according to step (2) is carried out. A variation of the tilt angle from 0 to 90 ° is possible, in FIG. 1 this is 45 ° by way of example.

The optical detection according to step (2) is preferably carried out with a detector. Use of PDA in step (2)

The procedure for determining the drop size distribution can be carried out using phase Doppler anemometry (PDA). This method is fundamentally known to the person skilled in the art, for example from F. Onofri et al., Part. Part. Sys. Charact. 1996, 13, pages 112-124 and A. Tratnig et al., J. Food. Engin. 2009, 95, pages 126-134. The PDA method is a measurement method which is based on the fact that an interference plane pattern is formed in the intersection volume of two coherent laser beams. The particles moving in a flow, such as the drops of the spray, i.e. sprays, which are examined in accordance with the present invention, scatter light as they cross the cutting volume of the laser beams with the so-called double frequency, which is directly proportional to the speed at the location of the measurement , The radius of curvature of the particle surface can be determined from the different phase position of the scattered light signal on preferably at least two detectors used, which are located at different locations in space. In the case of spherical particles, the particle diameter follows from this; in the case of drops, the respective pot diameter. For high measurement accuracy, it is advantageous to design the measurement setup, especially with regard to the scattering angle, so that a single scattering mechanism (first-order reflection or refraction) dominates. The scattered light signal is usually converted into electronic signals by photomultipliers and evaluated with the aid of covariance processors or with the aid of an FFT analysis (Fast Fourier Transformation Analysis) with regard to the Doppler frequency and the difference in the phase positions. The use of a Bragg cell preferably permits the controlled manipulation of the wavelength of one of the two laser beams and thus the generation of a current interference plane pattern.

PDA systems usually measure the phase shifts (ie the difference in phase positions) in received light signals by using different reception apertures (masks).

Preferably, a mask is used within step (2) of the method according to the invention in the case of implementation by means of PDA, by means of which drops are used a maximum possible drop diameter of 518.8 pm can be detected.

Appropriate devices suitable for carrying out the PDA process are commercially available, for example the Singie PDA from DantecDynamics (P60, Lexel Argon laser, FibreFlow).

When performing step (2), the PDA is preferably operated in forward scatter at an angle of 60-70 ° with a wavelength of 514.5 nm (orthogonally polarized) in reflection. The receiving optics preferably have a focal length of 500 mm, the transmitting optics preferably a focal length of 400 mm.

The optical measurement according to step (2) by means of a PDA is carried out traversing in the radial axial direction in relation to the tilted atomizer used, preferably at a tilt angle of 45 °. Basically, however, as mentioned above, tilt angles in a range from 0 to 90 °, preferably> 0 to <90 ° such as from 10 to 80 ° are possible. The optical measurement is preferably carried out 25 mm vertically below the flank of the atomizer inclined to the traversing axis. Measurements have shown a completed drop formation process at this position. Such a structure is shown as an example in FIG. 1. In this case, a defined traversing speed is preferably predefined, so that the individual detected events are resolved in terms of location via the associated temporally resolved signals. A comparison to grid-resolved measurements provides identical results for the weighted global distribution parameters, but still enables the examination of any interval ranges on the traversing axis. Furthermore, this method is many times faster than screening, which means that the material expenditure can be reduced with constant flow rates.

Use of TS in step (2)

Alternatively, or in addition to PDA technology, the time-shrft measurement technique can be used to determine the drop size distribution. The time shift procedure (TS) (also called time shift procedure (ZW)) is that Those skilled in the art are also generally known, for example from an article by W, Schäfer et al., ICLASS 2015, 13th Triennial International Conference on Liquid Atomization and Spray Systems, Tainan, Taiwan, pages 1 to 7 and an article by M. Kuhnhenn et al., ILASS Europe 2016, 27th Annual Conference on Liquid Atomization and Spray Systems, 4-7 September 2016, Brighton UK, pages 1 to 8 and from W. Schäfer et al., Particuology 2016, 29, pages 80-85.

The time shrft method (TS) is a measurement method which is based on the backscattering of light (for example laser light) by particles, as in the case of the present invention, by the drops of the spray mist (spray) resulting from the atomization. TS measurement technology is based on the light scattering of a single particle from a shaped light beam such as a laser beam. The scattered light of the individual particle is interpreted as the sum of all scatter orders at the location of the detector used. When approaching geometric optics, this corresponds to examining the propagation of individual light rays through the particle with a varying number of internal reflections. The laser beam used to carry out the time shift process is usually focused by lenses. The light that was scattered by the particles is divided into perpendicular and parallel polarized light and is preferably detected separately by at least two photodetectors. The signal coming from the detectors in turn provides the necessary information to determine a determination of the size of the droplets and / or homogeneity. The wavelength of the light of the illuminating beam used is of the same order of magnitude or is smaller than that of the particles to be measured. The laser beam should therefore be selected so that it does not exceed the size of the drops in order to obtain the time shift signal. If this value is exceeded, the signal is no longer suitable to serve as a basis for determining the above-mentioned variable. Otherwise there is the problem that the signal components of the different scatterings overlap and therefore cannot be recorded and differentiated individually. The time shift method can be used to determine characteristic properties of the particles, for example to determine the droplet size distribution. In addition, the time-shift method (TS) can be used to distinguish between bubbles, i.e. transparent drops (T) and solid-containing particles, i.e. non-transparent drops (NT). be distinguished. Appropriate devices suitable for this purpose are commercially available, for example devices from the SpraySpy @ series from AOM Systems. Carrying out traversing measurements using devices from the SpraySpy® series is known in principle, but is only used in the prior art to determine the width of the spray jet, but not to determine the homogeneity of the spray and / or parameters of the drop size distribution.

The optical measurement according to step (2) by means of TS is carried out traversing in the radial-axial direction in relation to the tilted atomizer used, preferably at a tilt angle of 45 °. Basically, however, as mentioned above, tilt angles in a range from 0 to 90 °, preferably> 0 to <90 ° such as from 10 to 80 ° are possible. The optical measurement is preferably carried out 25 mm vertically below the flank of the atomizer inclined to the traversing axis. Measurements have shown a completed drop formation process at this position. Such a structure is shown as an example in FIG. 1. In this case, a defined traversing speed is preferably specified so that the individual detected events are spatially resolved via the associated time-resolved signals. A comparison to grid-resolved measurements provides identical results for the weighted global distribution parameters, but still enables the examination of any interval ranges on the traversing axis. Furthermore, this method is many times faster than screening, which means that the material expenditure can be reduced with constant flow rates.

Step 3)

Step (3) of the method according to the invention provides for a determination of at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray on the basis of optical data obtained by the optical detection according to step (2).

As already mentioned above, the determination according to the invention of the drop size distribution of the drops formed by the atomization according to step (1) preferably includes the determination of corresponding ones known to the person skilled in the art Parameters such as the Di ₀ value (arithmetic diameter; "1, 0" moment), D ₃ o value (volume-equivalent mean diameter; "3.0" - moment), D ₃ 2 value (Sauter diameter (SMD ); "3.2" - moment), d _N, 50% value (number-related

Median value) and / or dv _, so% value (volume-related median value), at least one of these parameters of the drop size distribution being determined within step (3). In particular, the determination of the drop size distribution includes a determination of the D ₁₀ value of the drops. This takes place in particular if step (2) is carried out by means of a PDA and / or TS.

If step (2) is carried out by means of a PDA, the optical data obtained after carrying out step (2) are preferably evaluated using an algorithm for any tolerances within step (3). A tolerance of approx. 10% for the PDA system used limits the validation to spherical drops, an increase also includes slightly deformed drops. This enables an observation of the sphericity of the measured drops along the measurement axis.

If step (2) is carried out by means of TS, the optical data obtained after carrying out step (2) are preferably also evaluated using an algorithm for any tolerances.

The homogeneity of the spray describes the ratio of the two quotients Tn / Tiotaii and T _T 2 / Tto _ί3ΐ 2 to each other as a measure of the local distribution of transparent and non-transparent drops at two different positions within the spray, where Tn is the number of transparent drops in the first position 1, T _T 2 the number of transparent drops in the second position 2, Tfotaii the number of all drops in the spray and thus the sum of transparent drops and non-transparent drops in position 1 and T _To tai2 the number all drops of the spray and thus the sum of transparent drops and non-transparent drops at position 2, position 1 being closer to the center of the spray than position 2. The homogeneity can be determined in particular if TS is used when step (2) is carried out , Position 1, which is closer to the center of the spray than position 2, preferably represents an area segment within the spray which differs from position 2. Position 1 is - since it is closer to the center of the spray than position 2 - further inside the spray located as position 2, which is accordingly further outside in the spray, in any case further outside than position 1. If the spray is in the form of a cone, position 1 is further inside the cone than position 2. Both positions are preferably located 1 and 2 on a measuring axis that runs through the entire spray. This is shown as an example in FIG. 1. The distance between the two positions 1 and 2 within the spray is preferably at least 10%, preferably at least 15%, particularly based on the entire length of the part of the measuring axis which is located within the spray and which corresponds to a value of 100% preferably at least 20% and in particular at least 25% of this length of the measuring axis.

The data thus obtained by means of TS in accordance with step (2) can thus be evaluated for the transparent spectrum (T) and the non-transparent spectrum (NT) of the drops. The ratio of the number of measured drops of both spectra serves as a measure for the local distribution of transparent and non-transparent drops. An integral view along the measurement axis is possible. In particular, the ratio of the transparent drops (T) to the total number of drops (Total) is preferably determined at a position of x = 5 mm or x = 25 mm along the measurement axis. These positions then correspond to the aforementioned positions 1 (x = 5 mm) and 2 (x = 25 mm). The corresponding values are in turn put in relation to describe the homogeneity of the spray which changes from the inside out. Method according to the invention for creating and / or updating an electronic database

Another object of the present invention is a method for creating and / or updating an electronic database containing at least one parameter of the droplet size distribution within the spray and / or the homogeneity of the spray of atomized and different coating composition, the method comprising at least the steps (1) to (3), (4A) and (5A), namely

Steps (1), (2) and (3) according to the inventive method for determining the droplet size distribution within a spray and / or the homogeneity of this spray for a first coating composition (i), that is

(1) atomizing a first coating composition (i) using an atomizer, a spray being formed by the atomization,

(3) determining at least one characteristic of the droplet size distribution within the spray and / or the homogeneity of the spray on the basis of optical data obtained by the optical detection according to step (2), the homogeneity of the spray being the ratio of two quotients Tti / Tj tan and Tt2 / Tto _ίb ΐ2 to each other as a measure of the local distribution of transparent and non-transparent drops at two different positions within the spray, where T _{T1 is} the number of transparent drops at the first position 1, T _T 2 is the number of transparent ones Drops at the second position 2, T _To tan the number of all drops in the spray and thus the sum of transparent drops and non-transparent drops at position 1 and T _To tai2 the number of all drops in the spray and thus the sum of transparent drops and not - corresponds to transparent drops at position 2, position 1 being closer to the center of the spray than position 2,

(4A) incorporation of the at least one parameter of the droplet size distribution within the spray and / or of the determined homogeneity of the spray into an electronic database, determined for step (3) for the first coating composition (i), and

(5A) at least one simple repetition of steps (1) to (3) and (4A) for at least one further coating composition different from the first coating composition (i).

All of the preferred embodiments described above in connection with the method according to the invention for determining the drop size distribution within a spray and / or the homogeneity of this spray are also preferred embodiments with regard to the method for creating and / or updating an electronic database.

Preferably, the incorporation of the determined at least one parameter of the drop size distribution within the spray and / or the determined homogeneity of the spray into the database according to step (4A), as already stated above, also includes the incorporation of the respective standard deviations into the database. The standard deviation can take into account any inhomogeneity and / or incompatibility of the coating composition used in the atomization to a sufficient extent.

Step (5A) provides an at least simple repetition of steps (1) to (3) and (4A) for at least one further coating composition different from the first coating composition (i) as for at least one second coating composition (ii).

The repetition according to step (5A) is preferred for a multiplicity of corresponding, in each case different, coating composition carried out. The repetition is therefore at least one to x times, where x stands for a whole positive number> 2. Since the method according to the invention is a method for creating and / or updating an electronic database, there is no upper limit on the number of coating compositions to be used: the higher the number of repetition steps (5A) or the higher the number of repetition steps ( 5A), the more information regarding the characteristics of the droplet size distribution within the spray which occur during the atomization and / or the homogeneity of the spray of these compositions are incorporated into the database, which is of course advantageous. For example, the parameter x can range from 2 to 1,000,000 or from 5 or 10 or 50 or 100 to 1,000,000.

By means of the method according to the invention for creating and / or updating an electronic database, such an electronic database is preferably set up and updated continuously. This database then provides information about characteristics of the droplet size distribution within the spray and / or the homogeneity of the spray of a large number of different atomized coating compositions. The electronic database is preferably an online database. Step (4A) is preferably carried out by means of software support.

Preferably, when carrying out the method according to the invention

Creation and / or updating of an electronic database within step (4A) not only incorporates the determined parameters of the droplet size distribution within the spray and / or the homogeneity of the spray into the database, but also all process parameters that are necessary when performing steps (1) to (3) have been selected or specified. In addition to these process parameters or alternatively, all product parameters relating to the coating compositions used in the process according to the invention, in particular the respective recipes for their production and / or the components used for their production and their corresponding amounts, are preferably also incorporated into the database , The at least one further coating composition such as at least one coating composition (ii) used in step (5A) is different from the first coating composition (i). Likewise, all further coating agent compositions used in a repetition of step (5A) are different both from each of the coating agent compositions (i) and (ii) and from one another.

The at least one further coating composition such as at least one second coating composition (ii) used in step (5A) preferably has a pigment content which is identical to that of the first coating composition (i) or a pigment content which is increased by a maximum of ± 10% by weight. , particularly preferably by a maximum of ± 5% by weight, deviates from the pigment content of the coating composition (i), based on the amount of pigment present in the coating composition (i), and which also contains the identical pigment (s) ( e) or the pigment or pigments which are essentially identical to the coating composition (i). The same preferably applies to each of the other coating compositions used when step (5A) is repeated: each of these further coating compositions preferably has a pigment content which is identical to that of the first coating composition (I) or a pigment content which is at most ± 10 % By weight, particularly preferably by a maximum of ± 5% by weight, deviates from the pigment content of the coating composition (i), based on the amount of pigment present in the coating composition (i), and which also contains the identical (or n) contains pigment (s) or the substantially identical pigment (s) as the coating composition (i). If, for example, a certain effect pigment is used in the first coating agent composition (i), the identical effect pigment in the case of identical pigments is also present as an effect pigment in each of the other coating agent compositions used when step (5A) is repeated. In addition to steps (1) to (3), (4A) and (5A), the method according to the invention for creating an electronic database preferably also comprises at least the further steps (3A), (3B) and (3C), namely

(3A) Orders of the first atomized in step (1)

Coating composition (i) on a substrate to form a film on the substrate and baking this film to form a coating on the substrate,

(3B) Examination and assessment of the coating obtained after step (3A) with regard to the occurrence or non-occurrence of surface defects and / or optical defects and

(3C) incorporation of the results obtained after performing step (3B) into the electronic database, step (5A) of the method according to the invention in this case repeating these steps (3A), (3B) and (3C) for at least one more of the first coating composition (i) includes various coating compositions such as at least one second coating composition (ii).

In this way, the database created by means of the method according to the invention preferably contains not only the determined parameters of the droplet size distribution within the spray and / or the homogeneity of the spray of the coating compositions used, such as those of the coating compositions (i), (ii) and any other coating compositions used, but also data regarding the assessment of the coatings obtainable from each of these compositions with regard to the possible occurrence of surface defects and / or optical defects. In this way there is a direct correlation of the characteristics of the droplet size distribution within the spray and / or the homogeneity of the spray which occur and are determined during the atomization of the compositions with the occurrence or non-occurrence of surface defects and / or optical defects in or on the coating within the database. This data can then be called up from the database.

Metallic substrates are preferably used in step (3A). In principle, non-metallic substrates, in particular plastic substrates, are also possible. The substrates used can be coated. If a metal substrate is to be coated, this is preferably coated with an electro-dip coating before the filler or primer filler or the basecoat is applied. If a plastic substrate is coated, it is preferably pretreated before the filler or primer filler or the basecoat is applied. The most commonly used methods for this are flame treatment, plasma treatment and corona discharge. Flaming is preferably used. The coating compositions used, such as those of coating compositions (i), (ii) and any other coating composition used, are preferably basecoats, in particular waterborne basecoats. Accordingly, the coating obtained after step (3A) is preferably a basecoat film. The application of the basecoat or basecoats or lacquers to a metal substrate in step (3A) can be carried out in the layer thicknesses customary in the automotive industry in the range of, for example, 5 to 100 micrometers, preferably 5 to 60 micrometers, particularly preferably 5 to 30 micrometers. The substrate used preferably has one

Electrodeposition coating (ETL), particularly preferably an electrodeposition coating applied by means of cathodic deposition of an electrodeposition coating. Before baking, drying is preferably carried out according to known methods. For example, (I-component) base lacquers, which are preferred, can be flashed off at room temperature (23 ° C.) for 1 to 60 minutes and then preferably dried at optionally slightly elevated temperatures of 30 to 90 ° C. In the context of the present invention, ventilation and drying are understood to mean evaporation of organic solvents and / or water, as a result of which the paint is drier but not yet cured or no fully crosslinked paint film has yet been formed. The curing, that is to say the stoving, is preferably carried out thermally at temperatures from 60 to 200 ° C. Basically, plastic substrates are coated analogous to that of metal substrates. However, hardening is generally carried out at significantly lower temperatures of 30 to 90 ° C. Step (3A) can optionally include the application of a further coating agent composition and a hardening thereof after the first coating composition (i) atomized in step (1) has been applied to a substrate. In particular if the first coating composition (i) atomized in step (1) is a preferably aqueous basecoat, a commercially available clearcoat can be applied to it by customary methods, the layer thicknesses in turn being in the usual ranges, for example 5 to 100 micrometers. After the clear lacquer has been applied, it can be flashed off at room temperature (23 ° C.) for, for example, 1 to 60 minutes and optionally dried. The clear lacquer is then preferably hardened together with the applied atomized first coating composition (i), ie baked. Crosslinking reactions take place, for example, whereby an effect-giving and / or color-giving and effect-giving multilayer coating is produced on a substrate.

In step (3B), the occurrence or non-occurrence of surface defects and / or optical defects selected from the group of needle sticks, runners, stoves, streakiness and / or cloudyness is preferably examined and assessed and / or the appearance (optical appearance) of the coating examined and assessed. The coating is preferably a basecoat such as a waterborne basecoat. The examination and assessment of the occurrence of pinholes is carried out in accordance with the determination method described below by counting the pinpricks when the coating is wedged onto a substrate in accordance with step (3A) in a layer thickness range from 0 to 40 pm (dry layer thickness), the ranges from 0 to 20 pm and from> 20 to 40 pm can be counted separately, normalization of the results to an area of 200 cm ² and addition to a total number. A single pin prick is preferably already a defect. The examination and assessment of the occurrence of cookers is carried out in accordance with the determination method described below by determining the cooker limit, i.e. the layer thickness of a coating such as a basecoat layer from which cookers appear, in accordance with DIN EN ISO 28199-3, point 5. (Date: January 2010 ). A single cooker is preferably already a defect. The examination and assessment of the occurrence of cloudiness is carried out according to the determination method described below with the measuring device cloud-runner from BYK-Gardner GmbH, whereby the three parameters "Mottling15", "Mottling45" and "Motüng60" are measured as a measure of the cloudiness at angles of 15 °, 45 ° and 60 ° relative to the reflection angle of the light source used for the measurement, the cloudiness being more pronounced if the corresponding parameter (s) (a) higher value (s) has or have. The appearance is examined and assessed in accordance with the determination method described below by assessing the course when the coating is wedged onto a substrate in accordance with step (3A) in a layer thickness range from 0 to 40 pm (rock layer thickness), different ranges, for example from 10 -15 pm, 15-20 pm and 20-25 pm are marked and the examination and assessment is carried out using the Wave scan measuring device from Byk-Gardner GmbH within these layer thickness ranges. A laser beam is aimed at the surface to be examined at an angle of 60 ° and the fluctuations of the reflected light in the short wave range (0.3 to 1.2 mm) and in the long wave are measured over a measuring distance of 10 cm -Range (1, 2 to 12 mm) registered with the help of the measuring device (long wave = LW; short wave = SW; the lower the values, the better the course). The investigation and assessment of the occurrence of runners is carried out according to the determination method described below by determining the inclination of the run according to DIN EN ISO 28199-3, point 4. (Date: January 2010). A defect preferably occurs when runners appear from a layer thickness which is below a layer thickness which is 125% of the target layer thickness, for example if the target layer thickness is 12 pm, then a defect occurs if at a layer thickness of 12 pm + 25%, thus occur at 16 pm runners. The layer thicknesses are determined according to DIN EN ISO 2808 (date: May 2007), method 12A, preferably using the MiniTest® 3100- 4100 measuring device from ElektroPhysik. In all cases it is the rock layer thickness.

The terms “pinholes”, “cooker”, “runner” and “gradient” are known to the person skilled in the art, for example from the Römpp Chemie lexicon, paints and printing inks, 1998, 10th edition. The term cloudiness is also known to the person skilled in the art. Cloudiness of a coating is understood according to DIN EN ISO 4618 (date: January 2015) to be the inconsistent appearance of a coating, caused by irregular, arbitrarily distributed areas on the surface that differ in color and / or distinguish shine. Such a stain-like inhomogeneity disturbs the uniform overall impression of the coating and is generally undesirable. A method for determining cloudiness is given below. While the cloudiness is characterized by the aforementioned areas in the form of spots, the term “streakiness”, on the other hand, is a phenomenon caused by a poor overlap of spray jets, which causes regular stripe-shaped light and dark areas. A method for determining streakiness is given below.

Process according to the invention for screening coating compositions in the development of coating formulations

Another object of the present invention is a method for screening coating compositions in the development of

Coating formulations.

Steps (1) to (3) of the method for screening coating compositions in the development of paint formulations are identical to steps (1) to (3) of the method for determining the drop size distribution within a spray and / or the homogeneity of this spray. With regard to these steps, reference is therefore made to the above statements.

The method according to the invention for screening coating compositions in the development of coating formulations comprises at least steps (1) to (3), (4B), (5B) and (6B) and optionally (7B), namely Steps (1), (2) and (3) as they are within the inventive method for

Determination of the drop size distribution within a spray and / or the

Homogeneity of this spray are defined for one

So coating composition (X1)

(1) atomizing a coating composition (XI) using an atomizer, a spray being formed by the atomization,

(3) Determination of at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray on the basis of optical data obtained by the optical detection according to step (2), the homogeneity of the spray being based on the ratio of two quotients Tti / T o _t and Tre / Tjo _match each other as a measure of the local distribution of transparent and non-transparent drops at two different positions within the spray, where T _Ti indicates the number of transparent drops at the first position 1, TT2 the number of transparent drops the second position 2, T _Tot aii the number of all drops of the spray and thus the sum of transparent drops and non-transparent drops at position 1 and Tr ₀ tai2 the number of all drops of the spray and thus the sum of transparent drops and non-transparent drops Corresponds to position 2, position 1 being closer to the center of the spray than position 2,

(4B) Comparison of the at least one parameter of the droplet size distribution within the spray and / or the homogeneity of the spray determined according to step (3) for the coating composition (X1) with parameters of the droplet size distribution within the spray and / or the homogeneity stored in an electronic database the spray of further coating compositions, these Database is obtainable by means of the aforementioned method according to the invention for creating and / or updating an electronic database,

(5B) Check on the basis of the comparison according to step (4B) whether the at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray determined according to step (3) for the coating composition (X1) fulfills the condition that it is less is as at least one parameter stored in the database of the drop size distribution within the spray and / or the homogeneity of the spray of a coating composition (X2) which is different from the coating composition (X1) but has an identical pigment content to the coating composition (X1) or has such a pigment content which deviates by a maximum of ± 10% by weight from the pigment content of the coating composition (X1}, based on the amount of pigment present in the coating composition (X1), and which also contains the identical (or n) pigment (s) or the one or more iden like pigment (s) contains the coating composition (X1),

(6B) Selection of the coating composition (X1) for application to a substrate, if the at least one characteristic of the drop size distribution within the spray and / or the specific homogeneity of the spray determined for the coating composition (X1) meets the condition specified in step (5B) or

Adjusting at least one parameter within the recipe of the coating composition (X1) and / or at least one process parameter when carrying out steps (1) to (3) of the method for screening coating composition, if the at least one parameter determined for the coating composition (X1) Drop size distribution within the spray and / or the certain homogeneity of the spray does not meet the condition specified in step (5B),

(7B) at least one simple repetition of steps (1) to (3), (4B) and (5B), if at least one parameter adjustment was required in accordance with step (6B), until step (6B) was carried out at least once, based on to fulfill the condition mentioned in step (5B) according to step (6B), a selection of the coating composition used for application to a substrate is made.

The method according to the invention for screening coating compositions during the development of coating formulations thus enables adaptation in the sense of a reduction in the characteristics of the droplet size distribution within the spray and / or the homogeneity of the spray of coating composition such as the coating composition (X1) based on or compared to known corresponding parameters or homogeneities of comparison coating compositions such as the coating composition (X2).

In the context of the present invention, the term “essentially identical pigment” in connection with effect pigments means that the effect pigment (s) present in the coating composition (X1) and the effect pigment (s) present in the coating composition (X2) are the first condition (i) at least 80% by weight, preferably at least 85% by weight, particularly preferably at least 90% by weight, very particularly preferably at least 95% by weight, in particular at least 97.5% by weight, in each case based have an identical chemical composition based on their total weight, but preferably in each case less than 100% by weight. For example, effect pigments present in (X1) and (X2) are essentially identical if they are each aluminum effect pigments but have a different coating, such as chromating in one case and a silicate layer in the other or in one Case coated and in the other case not. Another additional condition (ii) for “essentially identical pigments” in the sense of the present invention in connection with effect pigments is that the effect pigments in their mean particle size should not exceed ± 20%, preferably ± 15 at most %, particularly preferably differ from each other by at most ± 10%. The average particle size is the arithmetic number average of the measured average particle diameter (d _N, 50 _% value), which is determined according to ISO 13320 (date: 2009) by laser diffraction. The term effect pigment per se is explained in more detail below and further.

In the context of the present invention in connection with color pigments, the term “essentially identical pigment” is understood to mean that that or those in the coating composition (X1) and that or that in the

Coating agent composition (X2) existing color pigments differ as a first condition (i) in their colourfulness from one another by at most ± 20%, preferably by at most ± 15%, particularly preferably by at most ± 10%, in particular by at most ± 5%. The colored booklet designates the a, fr-colorfulness CIE 1976 (CIELAB-colorfulness): and is determined according to DIN EN ISO 11664-4 (date: June 2012). A further additional condition (ii) for “essentially identical pigments” in the context of the present invention in connection with color pigments is that the color pigments have a mean particle size of at most ± 20%, preferably at most ± 15%, particularly preferably at most Differentiate ± 10% from each other. The average particle size is the arithmetic number average of the measured average particle diameter (d _{| \ i,} 50 _% value), which is determined according to ISO 13320 (date: 2009) by means of laser diffraction. The term color pigment per se is explained in more detail below and further.

In the event that, according to step (6B), the coating composition (X1) is selected for application to a substrate, the method according to the invention preferably includes at least the additional steps (6C), (6D) and (6E), namely (6C) Apply the coating composition (X1) to a

Substrate to form a film on the substrate and baking this film to form a coating on the substrate,

(6D) Examination and evaluation of the coating obtained after step (6C) with regard to the occurrence or non-occurrence of surface defects and / or optical defects and

(6E) Incorporation of the results obtained after performing step (6D) in an electronic database, preferably in the database obtainable by means of the method according to the invention for creating and / or updating an electronic database.

If the check based on the comparison according to step (4B) in step (5B) shows that there are no data stored in the database relating to a coating composition (X2) which has a pigment content identical to the coating composition (X1) or such a pigment Content which deviates by a maximum of ± 10% by weight from the pigment content of the coating composition (X1), based on the amount of pigment present in the coating composition (X1), and which does not contain the identical pigment (s) or if the pigment or pigments contains essentially the same pigment (s) as the coating composition (X1), step (6B) is preferably nevertheless carried out. When the aforementioned steps (6C), (6D) and (6E) are carried out further, the database obtainable by means of the method according to the invention for creating and / or updating an electronic database can be further updated.

The method according to the invention for screening coating composition compositions in the development of coating formulations preferably uses a database created and / or updated by means of the aforementioned method according to the invention for creating and / or updating an electronic database during step (4B) and / or (5B) to, to whose creation and / or updating in addition to steps (1) to (3), (4A) and (5A), at least the further steps (3A), (3B) and (3C) have been carried out, step (5A) being the Repetition of these steps (3A), (3B) and (3C) has included. In other words, the comparison according to step (4B) and / or the check according to step (5B) is preferably carried out on the basis of an electronic database, which not only determines the characteristic variable of the droplet size distribution within the spray and / or the determined homogeneity of the spray contains the coating composition used in the method according to the invention for creating and / or updating the database, but also the results of the investigations and assessments with regard to the occurrence or non-occurrence of surface defects and / or optical defects from them

Coating compositions prepared according to step (3A).

If the check according to step (5B) on the basis of the comparison according to step (4B) based on such a database that is preferably created and / or updated reveals that the database contains data relating to a coating composition (X2) that relates to the coating composition (X1 ) has an identical pigment content or has such a pigment content which deviates by a maximum of ± 10% by weight from the pigment content of the coating composition (X1), based on the amount of pigment present in the coating composition (X1), and which contains the identical pigment (s) or the substantially identical pigment (s) as the coating composition (X1), and their atomization to a determined parameter of the droplet size distribution within the spray and / or certain homogeneity of the Sprays, which is already less than the determined parameter of Droplet size distribution within the spray and / or the determined homogeneity of the spray of the coating composition (X1), at least one parameter is adjusted in accordance with step (6B) as explained above. Adjusting at least one parameter within the recipe

Coating agent composition (X1) according to step (6B) preferably comprises at least one adjustment selected from the group of adjustments of the following parameters:

(i) increasing or decreasing the amount of at least one in the

Coating agent composition (X1) as a binder component (a) containing polymer,

(ii) at least partial exchange of at least one in the

Coating agent composition (X1) as binder component (a) containing polymers by at least one polymer different from this,

(iii) increasing or decreasing the amount of at least one in the

Coating composition (X1) as component (b) containing pigment and / or filler, this being possible for pigments contained therein only within the aforementioned framework,

(iv) at least partial exchange of at least one of the

Coating agent composition (X1) as component (b) containing filler by at least one different filler,

(v) increasing or decreasing the amount of at least one in the

Coating agent composition (X1) as component (c) organic solvent and / or contained therein

Water,

(vi) at least partial exchange of at least one in the

Coating agent composition {X1) organic solvent contained as component (c) by at least one organic solvent different therefrom,

(vii) increasing or decreasing the amount of at least one in

Coating composition (X1) as component (d) containing additive,

(viii) at least partial exchange of at least one in the

Coating agent composition (X1) as component (d) contained additive by at least one additive different from this, and / or adding at least one further additive different from this,

(ix) change the order of manufacture of the

Coating agent composition (X1) used

Components and / or

(x) increase or decrease the energy input of the

Mixing in the manufacture of the

Coating agent composition (X1).

In particular, the spray viscosity of the

Coating agent composition (X1) are increased or decreased, parameters (vii) and / or (viii) include / include in particular the exchange and / or the addition of thickeners as additives or the change in their amount in (X1), such thickeners are described below in Parameters (i) and / or (ii) described in more detail in the context of component (d) include / comprise, in particular, the exchange and / or the addition of binders or the change in their amount in (X1). The term binder is explained in more detail below. Crosslinkers (crosslinking agents) are also to be subsumed under this. Accordingly, parameters (i) and / or (ii) also include a change in the relative weight ratio of crosslinking agent and that binder component which undergoes a crosslinking reaction with the crosslinking agent, parameters (i) to (iv) include / include in particular the exchange and / or the addition of binders and / or pigments or the change in their amount in (X1). Accordingly, these parameters (i) to (iv) also implicitly include a change in the pigment / binder ratio within (X1),

All of the preferred embodiments described above in connection with the method according to the invention for determining the drop size distribution within a spray and / or the homogeneity of this spray and the method according to the invention for creating and / or updating an electronic database are also preferred embodiments with regard to the method for screening Coating compositions in the development of

Coating formulations.

In step (1) of the process according to the invention, a basecoat, particularly preferably an aqueous basecoat, is preferably used as the coating composition, in particular an aqueous basecoat which contains at least one pigment such as an effect pigment. In this respect, the method according to the invention for the screening of coating compositions in the development of coating formulations relates in particular to the screening of aqueous basecoats which contain at least one pigment such as an effect pigment and is therefore its quantity taking into account the influence of the nature of the at least one pigment contained therein such as an effect pigment , based on the total weight of the basecoat, and / or the pigment-binder ratio in the basecoat.

By means of the method according to the invention it is in particular possible, on the basis of the determined determination of at least one parameter of the droplet size distribution within the spray, such as the Di ₀ value and / or the homogeneity of this spray, to investigate and in particular to improve certain desired properties by means of atomization to achieve coatings to be produced, in particular with regard to avoiding or at least reducing the tendency to form or the occurrence of optical defects and / or surface defects. In particular, a reduction in needlesticks or an increase in the robustness of the needlesticks, an improvement in the course and a reduction / avoidance of cloudiness and streakiness are to be mentioned here.

The method according to the invention contains at least steps (1) to (3), (4B), (5B) and (6B) and optionally (7B), but can optionally also comprise further steps. Steps (1) to (3), (4B), (5B) and <6B) are preferably carried out in numerical order. However, the method preferably does not contain a step which provides for curing or baking of the coating composition (X1) used. Coating compositions used in the process of the invention

The following embodiments relate both to the method according to the invention for determining the droplet size distribution and / or homogeneity of the spray and also to the method according to the invention for creating an electronic database and to the method according to the invention for screening coating compositions in the development of coating formulations. The embodiments described below relate in particular to the aforementioned coating compositions (X1), (X2), (i) and (ii).

The coating composition used according to the invention preferably contains

At least one polymer which can be replaced as binder as component (a),

• at least one pigment and / or at least one filler as a component

(Federation

• Water and / or at least one organic solvent as component (c).

The term “comprising” or “containing” in the sense of the present invention, in particular in connection with the coating composition used according to the invention, preferably has the meaning “consisting of”. With regard to the coating composition used according to the invention, for example, in addition to components (a), (b) and (c), one or more of the further optional components mentioned below can be contained therein. All components can each be present in their preferred embodiments mentioned below.

The coating composition used according to the invention is preferably a coating composition that can be replaced in the automotive industry. Both coating compositions can be used, which can be used in the context of OEM series painting as well as in the context of a refinishing. In the Automotive coating compositions which can be replaced in the automotive industry are, for example, electrocoat materials, primers, fillers, basecoats, in particular waterborne basecoats (aqueous basecoats), topcoats, including clearcoats, in particular solvent-based clearcoats. The use of water-based paints is particularly preferred.

The term basecoat is known to the person skilled in the art and is defined, for example, in the Römpp Lexicon, Lacquers and Printing Inks, Georg Thieme Verlag, 1998, 10th edition, page 57. Accordingly, a basecoat in particular includes a coloring and / or used in automotive painting and general industrial painting to understand coloring and an optical effect intermediate coating material. This is generally applied to a metal or plastic substrate pretreated with filler or primer, sometimes directly on the plastic substrate. Old paintwork, which may need to be pretreated (e.g. by sanding), can also serve as substrates. It is now quite common to apply more than one base coat. Accordingly, in such a case, a first basecoat layer forms the background for a second. To protect a basecoat layer, in particular against environmental influences, at least one additional clearcoat layer is applied to it. A waterborne basecoat is an aqueous basecoat in which the proportion of water is> the proportion of organic solvents, based on the total weight of water and organic solvents in% by weight within the waterborne basecoat.

The proportions in% by weight of all used in the invention

Components containing coating composition such as components (a), (b) and (c) and optionally one or more of the further optional components mentioned below add up to 100% by weight, based on the total weight of the coating composition.

The solids content of the coating composition used according to the invention is preferably in a range from 10 to 45% by weight, particularly preferably from 11 to 42.5% by weight, very particularly preferably from 12 to 40% by weight, in particular from 13 to 37 , 5 wt.%, Each based on the Total weight of the coating composition. The solids content, i.e. the non-volatile content, is determined using the method described below.

Component (a)

For the purposes of the present invention, in accordance with DIN EN ISO 4618 (German version, date: March 2007), the term “binding agent” preferably refers to the non-volatile fractions of a composition such as the coating composition used in accordance with the invention, with the exception of those therein contained pigments and / or fillers understood. The non-volatile content can be determined according to the method described below. A binder component is accordingly any component which contributes to the binder content of a composition such as the coating composition used according to the invention. An example is a basecoat such as an aqueous basecoat which contains at least one polymer which can be replaced as a binder as component (a), for example an SCS polymer described below, a crosslinking agent such as a melamine resin and / or a polymeric additive.

A so-called seed-core-shell polymer (SCS polymer) is particularly preferably used as component (a). Such polymers or aqueous dispersions containing such polymers are known for example from WO 2016/116299 A1. The polymer is preferably a (meth) acrylic copolymer. The polymer is preferably used in the form of an aqueous dispersion. A very particularly preferred component (a) is a polymer having an average particle size in the range from 100 to 500 nm, which can be prepared by successive radical emulsion polymerization of three preferably different monomer mixtures (A), (B) and (C) of olefinically unsaturated monomers in water, the mixture (A) containing at least 50% by weight of monomers with a solubility in water of less than 0.5 g / l at 25 ° C. and a polymer which is obtained from the Mixture (A) is prepared, has a glass transition temperature of 10 to 65 ° C,

the mixture (B) contains at least one polyunsaturated monomer and a polymer which is prepared from the mixture (B) has a glass transition temperature of -35 to 15 ° C., and

a polymer which is produced from the mixture (C) has a glass transition temperature of -50 to 15 ° C,

and where

i. the mixture (A) is first polymerized,

ii. then the mixture (B) in the presence of the i. prepared polymer is polymerized, and

iii. then the mixture (C) in the presence of the under ii. prepared polymer is polymerized. The preparation of the polymer comprises the successive radical emulsion polymerization of three mixtures (A), (B) and (C) of olefinically unsaturated monomers, each in water. It is therefore a multi-stage radical emulsion polymerization, i. the mixture (A) is polymerized first, then ii. in the presence of the i. prepared polymer, the mixture (B) is polymerized and further iii. in the presence of the under ii. prepared polymer, the mixture (C) is polymerized. All three monomer mixtures are thus polymerized via a free-radical emulsion polymerization (that is to say a stage or also a polymerization stage) which is carried out separately, these stages taking place in succession. In terms of time, the stages can take place one after the other. It is also possible that after the completion of one stage the corresponding reaction solution is stored for a certain period of time and / or transferred to another reaction vessel and only then is the next stage carried out. In addition to the polymerization of the monomer mixtures (A), (B) and (C), the preparation of the polymer preferably comprises no further ones

Polymerization.

Mixtures (A), (B) and (C) are mixtures of olefinically unsaturated monomers. Suitable olefinically unsaturated monomers can be mono- or poly-olefinically unsaturated. Examples of suitable mono-olefinically unsaturated monomers include in particular (meth) acrylate-based mono-olefin-unsaturated monomers, mono-olefin-unsaturated monomers containing allyl groups and other mono-olefin-unsaturated monomers containing vinyl groups, such as, for example, vinyl-aromatic monomers. The term (meth) acrylic or (meth) acrylate in the context of the present invention encompasses both methacrylates and acrylic fates. In any case, but not exclusively, (meth) acrylate-based mono-olefinically unsaturated monomers are preferably used.

Mixture (A) contains at least 50% by weight, preferably at least 55% by weight, of olefinically unsaturated monomers with a water solubility of less than 0.5 g / i at 25 ° C. A corresponding preferred monomer is styrene. The solubility of the monomers in water is determined using the method described below. The monomer mixture (A) preferably does not contain any hydroxy-functional monomers. The monomer mixture (A) likewise preferably does not contain any acid-functional monomers. The monomer mixture (A) very particularly preferably does not contain any monomers with functional groups containing heteroatoms. This means that heteroatoms, if any, are only in the form of bridging groups. This is the case, for example, in the (meth) acrylate-based, simple olefinically unsaturated monomers described above which have an alkyl radical as the radical R. The monomer mixture (A) preferably contains only mono-olefinically unsaturated monomers. The monomer mixture (A) preferably contains at least one monounsaturated ester of (meth) acrylic acid with an alkyl radical and at least one vinyl group-containing monolefinically unsaturated monomer with a radical arranged on the vinyl group which is aromatic or which is mixed, saturated, aliphatic-aromatic , in which case the aliphatic portions of the radical are alkyl groups. The monomers contained in the mixture (A) are selected so that a polymer produced therefrom has a glass transition temperature of 10 to 65 ° C., preferably 30 to 50 ° C. The glass transition temperature can be determined using the method described below. That in stage i. Polymer produced by the emulsion polymerization of the monomer mixture (A) is also referred to as seed. The seeds are preferred an average particle size of 20 to 125 nm (measured by means of dynamic light scattering as described below; see determination methods

Mixture (B) contains at least one polyolefinically unsaturated monomer, preferably at least one polyolefinically unsaturated monomer. A corresponding preferred monomer is hexanediol diacrylate. Preferably contains the

Monomer mixture (B) no hydroxyl-functional monomers. The monomer mixture (B) likewise preferably does not contain any acid-functional monomers. The monomer mixture (B) very particularly preferably does not contain any monomers with functional groups containing heteroatoms. This means that heteroatoms, if present, are only in the form of verb-shifting groups. This is the case, for example, in the (meth) acrylate-based, simple olefinically unsaturated monomers described above which have an alkyl radical as the radical R. In addition to the at least one polyolefinically unsaturated monomer, the monomer mixture (B) preferably also comprises the following monomers: firstly at least one monounsaturated ester of (meth) acrylic acid with an alkyl radical and secondly at least one monolefinically unsaturated monomer containing vinyl groups with one of the vinyl group which is aromatic or which is mixed saturated-aliphatic-aromatic, in which case the aliphatic portions of the radical are alkyl groups. The proportion of polyunsaturated monomers is preferably from 0.05 to 3 mol%, based on the total molar amount of monomers of the monomer mixture (B). The monomers contained in the mixture (B) are selected so that a polymer produced therefrom has a glass transition temperature of -35 to 15 ° C., preferably of -25 to + 7 ° C. The glass transition temperature can be determined using the method described below. That in stage ii. polymer produced by the emulsion polymerization of the monomer mixture (B) in the presence of the seeds is also referred to as the core. After stage ii. the result is a polymer which comprises the seed and the core. The polymer, which after stage ii. obtained, preferably has an average particle size of 80 to 280 nm, preferably 120 to 250 nm (measured by means of dynamic light scattering as described below; if necessary, determination methods). The monomers contained in the mixture (C) are selected so that a polymer produced therefrom has a glass transition temperature of from -50 to 15 ° C., preferably from -20 to + 12 ° C. The glass transition temperature can be determined using the method described below. The olefinically unsaturated monomers of the mixture (C) are preferably selected so that the resulting polymer, comprising the seed, core and shell, has an acid number of 10 to 25. Accordingly, the mixture (C) preferably contains at least one alpha-beta unsaturated carboxylic acid, particularly preferably (meth) acrylic acid. The olefinically unsaturated monomers of the mixture (C) are additionally or alternatively preferably selected so that the resulting polymer, comprising seeds, cores and shells, has an OH number of 0 to 30, preferably 10 to 25. All the acid numbers and OH numbers mentioned above are values calculated on the basis of the total monomer mixtures used. The monomer mixture (C) preferably contains at least one alpha-beta unsaturated carboxylic acid and at least one monounsaturated ester of (meth) acrylic acid with an alkyl radical substituted by a hydroxyl group. The monomer mixture (C) particularly preferably contains at least one alpha-beta unsaturated carboxylic acid, at least one monounsaturated ester of (meth) acrylic acid with an alkyl radical substituted by a hydroxyl group and at least one monounsaturated ester of (meth) acrylic acid with an alkyl radical. If an alkyl radical without further specification is mentioned in the context of the present invention, this is always to be understood as a pure alkyl radical without functional groups and heteroatoms. That in stage iii. Polymer produced by the emulsion polymerization of the monomer mixture (C) in the presence of seeds and seeds is also referred to as a shell. After stage iii. the result is a polymer which comprises seeds, seeds and husk, ie polymer (b). After its preparation, the polymer (b) has an average particle size of 100 to 500 nm, preferably 125 to 400 nm, very particularly preferably 130 to 300 nm (measured by means of dynamic light scattering as described below; cf. determination methods.)

The coating composition used according to the invention preferably contains a proportion of component (a) such as at least one SCS polymer in a range from 1.0 to 20% by weight, particularly preferably from 1.5 to 19% by weight, very particularly preferably from 2.0 to 18.0% by weight, in particular from 2.5 to 17.5% by weight, most preferably from 3.0 to 15.0% by weight. -%, each based on the total weight of the coating composition. The determination or determination of the proportion of component (a) in the coating composition can be carried out by determining the solids content (also called non-volatile content, solids content or solids content) of an aqueous dispersion containing component (a).

Additionally or alternatively, preferably additionally, to the at least one previously described SCS polymer as component (a), the coating composition used according to the invention can contain at least one of the

Polymer containing different polymer as a binder of component (a), in particular at least one polymer selected from the group consisting of polyurethanes, polyureas, polyesters, poly (meth) acrylates and / or copolymers of the polymers mentioned, in particular polyurethane poly (meth) acrylates and / or polyurethane polyureas.

Preferred polyurethanes are described, for example, in German patent application DE 199 48 004 A1, page 4, line 19 to page 11, line 29 {polyurethane prepolymer B1), in European patent application EP 0 228 003

A1, page 3, line 24 to page 5, line 40, in European patent application EP 0 634 431 A1, page 3, line 38 to page 8, line 9, and international patent application WO 92/15405, page 2, line 35 to page 10, line 32.

Preferred polyesters are, for example, in DE 4009858 A1 in column 6, line 53 to column 7, line 61 and column 10, line 24 to column 13, line 3 or WO 2014/033135 A2, page 2, line 24 to page 7, line 10 and page 28, line 13 to page 29, line 13.

Preferred polyurethane-poly (meth) acrylate copolymers ((meth) acrylated polyurethanes) and their preparation are described, for example, in WO 91/15528 A1, page 3, line 21 to page 20, line 33 and in DE 4437535 A1, page 2, line 27 to page 6, line 22. Preferred polyurethane-polyurea copolymers are polyurethane

Polyurea particles, preferably those with an average particle size of 40 to 2000 nm, the polyurethane-polyurea particles, in each case in reacted form, at least one polyurethane prepolymer containing socyanate groups, containing anionic and / or groups which can be converted into anionic groups, and at least a polyamine containing two primary amino groups and one or two secondary amino groups. Such copolymers are preferably used in the form of an aqueous dispersion. Such polymers can in principle be produced by known polyaddition of, for example, polyisocyanates with polyols and polyamines. The mean particle size of such polyurethane-polyurea particles is determined as described below (measured by means of dynamic light scattering as described below; cf. determination methods).

The proportion of such polymers different from the SCS polymer in the

The coating composition is preferably smaller than the proportion of the SCS polymer. The polymers described are preferably hydroxyfunctional and particularly preferably have an OH number in the range from 15 to 200 mg

KOH / g, particularly preferably from 20 to 150 mg KOH / g.

The coating compositions used according to the invention particularly preferably comprise at least one hydroxy-functional polyurethane-poly (meth) acrylic copolymer, again preferably at least one hydroxy-functional polyurethane-poly (meth) acrylate copolymer and at least one hydroxy-functional polyester and optionally a preferably hydroxy-functional polyurethane-polyurea copolymer.

The proportion of the other polymers as binders of component (a) - in addition to an SCS polymer - can vary widely and is preferably in the range from 1.0 to 25.0% by weight, preferably 3.0 to 20.0% by weight .-%, particularly preferably 5.0 to 15.0 wt .-%, each based on the total weight of the

Mitel coating composition In addition, the coating composition can contain at least one typical crosslinking agent known per se! contain. If it contains a crosslinking agent, it is preferably at least one aminoplast resin and / or at least one blocked or free polyisocyanate, preferably an aminoplast resin. Among the aminoplast resins, melamine resins are particularly preferred. If the coating composition contains crosslinking agents, the proportion of these crosslinking agents, in particular aminoplast resins and / or blocked or free polyisocyanates, particularly preferably aminoplast resins, including preferably melamine resins, is preferably in the range from 0.5 to 20.0% by weight, preferably 1.0 up to 15.0% by weight, particularly preferably 1.5 to 10.0% by weight, in each case based on the total weight of the coating composition. The proportion of crosslinking agent is preferably smaller than the proportion of the SCS polymer in the coating composition.

Component (b)

A specialist is familiar with the terms “pigments” and “fillers”.

The term “filler is known to the person skilled in the art, for example from DIN 55943 (date: October 2001). For the purposes of the present invention, a “filler” is preferably understood to mean a component which is essentially, preferably completely, insoluble in the coating composition used according to the invention, such as, for example, a waterborne basecoat, which component is used in particular to increase the volume. For the purposes of the present invention, “fillers” preferably differ from “pigments” by their refractive index, which is <1.7 for fillers. Any customary filler known to those skilled in the art can be used as component (b). Examples of suitable fillers are kaolin, dolomite, calcite, chalk, calcium sulfate, barium sulfate, graphite, silicates such as magnesium silicates, in particular corresponding sheet silicates such as hectorite, bentonite, montmorillonite, talc and / or mica, silicas, in particular pyrogenic silicas, hydroxides such as aluminum hydroxide or magnesium hydroxide or organic fillers such as textile fibers, cellulose fibers, polyethylene fibers or polymer powder. The term “pigment” is also known to the person skilled in the art, for example from DIN 55943 (date: October 2001). For the purposes of the present invention, a “pigment” is preferably understood to mean powder or platelet-shaped components which are essentially, preferably completely, insoluble in the coating composition used according to the invention, such as a water-based lacquer. These are preferably colorants and / or substances which, owing to their magnetic, electrical and / or electromagnetic properties, can be used as pigments. Pigments differ from "fillers" preferably by their refractive index, which is £ 1.7 for pigments.

Colored pigments and effect pigments are preferably subsumed under the term “pigments”.

A person skilled in the art is familiar with the term color pigments. The terms “coloring pigment” and “color pigment” are interchangeable in the sense of the present invention. A corresponding definition of the pigments and further specifications thereof is regulated in DIN 55943 (date: October 2001). Inorganic and / or organic pigments can be used as the color pigment. White, colored and / or black pigments are used as particularly preferred color pigments. Examples of white pigments are titanium dioxide, zinc white, zinc sulfide and lithopone. Examples of black pigments are carbon black, iron-manganese black and spinel black. Examples of color pigments are chromium oxide, chromium, cobalt green, ultramarine green, cobalt blue, ultramarine blue, manganese blue, ultramarine violet, cobalt and manganese violet, Eisenoxi red, cadmium, molybdenum red and ultramarine, iron oxide brown, mixed brown, spinel and corundum and chrome orange, yellow iron oxide, nickel titanium yellow, chrome titanium yellow , Cadmium sulfide, cadmium zinc sulfide, chrome yellow and bismuth vanadate.

A person skilled in the art is familiar with the term effect pigments. A corresponding definition can be found, for example, in the Römpp Lexikon, Lacke und Druckfarben, Georg Thieme Verlag, 1998, 10th edition, pages 176 and 471. A definition of pigment gene in general and further specifications thereof are in the DIN 55943 (date: October 2001). Preferably, in effect pigments, such pigments _"the optical effect giving or color and optical effect _factor" are, in particular optical effect factor _". The terms _»» optical effect pigment and coloring pigment _{"» »»} optical effect pigment "and" Effektpigmenf are therefore preferably interchangeable. Preferred effect pigments are, for example plätchenförmige metal effect pigments such as blätchenförmige aluminum pigments, gold bronzes, fire-colored bronzes and / or iron oxide aluminum pigments _"pearlescent pigments such as pearl _essence" basic lead carbonate _» bismuth oxychloride and / or metal oxide mica pigments (mica) and / or other effect pigments such as flaky graphite _» flaky iron oxide _» multilayer effect pigments made from PVD films and / or liquid crystal polymer pigments _» Especially flake-shaped aluminum pigments and metal oxide mica pigments.

The coating composition used according to the invention, for example a waterborne basecoat, particularly preferably comprises at least one effect pigment as component (b).

Preferably, the coating agent used in the invention contains the composition a proportion of effect pigment as the component (b) in a range of 1 to 20 wt, -% _"more preferably from 1, 5 to 18 wt .-%, most preferably from 2 to 16 weight %, in particular from 2.5 to 15% by weight, most preferably from 3 to 12% by weight or from 3 to 10% by weight, in each case based on the total weight of the coating composition. The total proportion of all pigments and / or fillers in the coating composition is preferably in the range from 0.5 to 40.0% by weight, more preferably from 2.0 to 20.0% by weight, particularly preferably from 3.0 to 15.0% by weight, based in each case on the total weight of the coating composition.

The relative weight ratio of component (b) such as at least one effect pigment to component (a) such as at least one SCS polymer in the coating composition is in a range from 4: 1 to 1: 4, particularly preferably in a range from 2: 1 up to 1: 4, very special preferably in a range from 2: 1 to 1: 3, in particular in a range from 1: 1 to 1: 3 or from 1: 1 to 1: 2.5.

Component (c)

The coating composition used according to the invention is preferably aqueous. It is preferably a system which mainly uses water as the solvent (ie as component (c)), preferably in an amount of at least 20% by weight, and organic solvents in smaller proportions, preferably in an amount of <20% by weight .-%, each based on the total weight of the coating composition.

The coating composition used according to the invention preferably contains a proportion of water of at least 20% by weight, particularly preferably at least 25% by weight, very particularly preferably at least 30% by weight, in particular at least 35% by weight, in each case on the total weight of the coating composition.

The coating composition used according to the invention preferably contains a proportion of water which is in a range from 20 to 65% by weight, particularly preferably in a range from 25 to 60% by weight, very particularly preferably in a range from 30 to 55% by weight. -%, based in each case on the total weight of the coating composition.

The coating composition used according to the invention preferably contains a proportion of organic solvents which is in a range from <20% by weight, particularly preferably in a range from 0 to <20% by weight, very particularly preferably in a range from 0.5 to <20 wt .-% or up to 15 wt .-%, each based on the total weight of the

Mitel coating composition.

Examples of such organic solvents are heterocyclic, aliphatic or aromatic hydrocarbons, mono- or polyhydric alcohols, in particular methanol and / or ethanol, ethers, esters, ketones and amides, such as. B. N-methylpyrrolidone _» N-ethylpyrrolidone, dimethylformamide, toluene, xylene, butanol,

Ethyl and butyl glycol and their acetates, butyl diglycol, diethylene glycol dimethyl ether, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, acetone, isophorone or mixtures thereof

Other optional components

The coating composition used according to the invention may optionally also contain at least one thickener (also referred to as thickener) as component (d). Examples of such thickeners are inorganic thickeners, for example metal silicates such as layered silicates, and organic thickeners, for example poly (meth) acrylic acid thickeners and / or (meth) acrylic acid (meth) acrylate copolymer thickeners, polyurethane thickeners and polymeric waxes. The metal silicate is preferably selected from the group of smectites. The smectites are particularly preferably selected from the group of montmorillonites and hectorites. In particular, the montmorillonites and hectorites are selected from the group consisting of aluminum-magnesium silicates and sodium-magnesium and sodium-magnesium-fluorine-lithium layered silicates. These inorganic layered silicates are sold, for example, under the Laponite® brand. Thickeners based on poly (meth) acrylic acid and (meth) acrylic acid (meth) acrylate copolymer thickeners are optionally crosslinked and / or neutralized with a suitable base. Examples of such thickeners are “alkali swellable emulsions” (ASE), and hydrophobically modified variants thereof, the “hydrophobically modified alkali swellable emulsions” (HASE). These thickeners are preferably anionic. Corresponding products such as Rheovis® AS 1 130 are commercially available. Thickeners based on polyurethanes (eg polyurethane associative thickeners) are optionally crosslinked and / or neutralized with a suitable base. Corresponding products such as Rheovis® PU 1250 are commercially available. Examples of suitable polymeric waxes are modified polymeric waxes based on ethylene-vinyl acetate copolymers. A corresponding product is commercially available, for example, under the name Aquatix® 8421. Depending on the desired application, the coating composition used in accordance with the invention can contain one or more commonly used additives as further component (s) (d). For example, the coating composition can contain at least one additive selected from the group consisting of reactive diluents, light stabilizers, antioxidants, deaerating agents, emulsifiers, slip additives, polymerization inhibitors, initiators for radical polymerizations, adhesion promoters, leveling agents, film-forming aids, sag control agents (SCAs), flame retardants. Contain corrosion inhibitors, siccatives, biocides and matting agents. They can be used in the known and customary proportions.

The coating composition used according to the invention can be produced using the customary and known mixing processes and mixing units.

Positioning methods

1. Determination of the non-volatile portion

The non-volatile content (of the solid) is determined in accordance with DIN EN ISO 3251 (date: June 2008). 1 g of sample are weighed into a previously dried aluminum dish and dried in a drying cabinet for 60 minutes at 125 ° C., cooled in a desiccator, and then weighed back. The residue based on the total amount of the sample used corresponds to the non-volatile fraction. If necessary, the volume of the non-volatile component can be determined in accordance with DIN 53219 (date: August 2009).

2. Determination of number average molecular weight

Unless stated otherwise, the number-average molecular weight (M _n ) is determined using a steam pressure osmometer type 10.00 (Knauer) on series of concentrations in toluene at 50 ° C. with benzophenone as calibration substance to determine the experimental moose constant of the measuring device used according to E. Schröder, G. Müller, K.-F. Arndt, "Guide to Polymer Characterization", Akademie-Verlag, Berlin, pp. 47-54, 1982.

3. Determination of the OH number and the acid number

The OH number and the acid number are each determined by calculation.

4. Determination of the average particle size of SCS polymers and

Polyurethane-Polvharnstoff particles

The mean particle size is determined using dynamic light scattering (photon correlation spectroscopy) (PCS) based on DIN ISO 13321 (date: October 2004). A “Malvern Nano S90” (from Malvern Instruments) at 25 ± 1 ° C is used for the measurement. The device covers a size range from 3 to 3000 nm and is equipped with a 4mW He-Ne laser at 633 nm. The respective samples are diluted with particle-free, deionized water as the dispersion medium and then measured in a 1 ml polystyrene cuvette with a suitable scattering intensity , The evaluation was carried out using a digital correlator with the aid of the evaluation software Zetasizer Vers. 7.11 (Fa. Malvern Instruments). It is measured five May and the measurements are repeated on a second, freshly prepared sample. With regard to the SCS polymer, the mean particle size is understood to mean the arithmetic number mean of the measured mean particle diameter (Z-average mean; number average; d _N .so _% value). The standard deviation of a 5-fold determination is £ 4%. With regard to the replaceable polyurethane-polyurea particles, the mean particle size is understood to mean the arithmetic volume mean from the mean particle size of the individual preparations (V-average mean; volume mean; dv, 50 _% value). The maximum deviation of the volume mean from five individual measurements is ± 15%. The check is carried out using polystyrene standards with certified particle sizes between 50 and 3000 nm,

5. Determination of the layer thicknesses

The layer thicknesses are determined in accordance with DIN EN ISO 2808 (date: May 2007), method 12A, using the MiniTest® 3100-4100 measuring device from ElektnoPhysik.

6. Assessment of the occurrence of needlesticks and the course depending on the layer thickness

To assess the occurrence of pinholes and the layer thickness-dependent course, wedge-shaped multi-layer coatings are produced according to the following general instructions

A sheet of steel measuring 30 x 50 cm coated with a standard KTL (CathoGuard® 800 from BASF Coatings GmbH) is provided with an adhesive strip (Tesa tape, 19 mm) on one longitudinal edge in order to be able to determine differences in layer thickness after coating. A waterborne basecoat is applied electrostatically as a wedge with a target layer thickness (layer thickness of the dried material) of 0-40 pm. The outflow rate is between 300 and 400 ml / min; the speed of the ESTA bell is varied between 23,000 and 43,000 rpm; the exact details of the application parameters selected in each case are given below within the experimental section. After a flash-off time of 4-5 minutes at room temperature (18 to 23 ° C), the assembly is dried in a forced air oven at 60 ° C for 10 minutes. To Removing the adhesive strip is manually applied to the dried water-based coating layer using a flow cup gun using a commercially available two-component clear coat (ProGloss® from BASF Coatings GmbH) with a target layer thickness (layer thickness of the dried material) of 40-45 pm. The resulting clear lacquer layer is flashed off at room temperature (18 to 23 ° C.) for 10 minutes; Then the curing takes place in a convection oven at 140 ° C for a further 20 minutes.

The occurrence of pinholes is assessed visually according to the following general rule: The dry film thickness of the waterborne basecoat is checked and for the basecoat film thickness wedge the ranges from 0 to 20 pm and from 20 pm to the end of the wedge are marked on the steel sheet. The pinholes are evaluated visually in the two separate areas of the water-based lacquer wedge. The number of needle stitches is counted for each area. All results are normalized to an area of 200 cm ² and then added to a total number. In addition, a record is made of the dry layer thickness of the water-based lacquer wedge at which needle sticks no longer occur.

The course of the course, which is dependent on the layer thickness, is assessed according to the following general rule: the dry layer thickness of the waterborne basecoat is checked, and different areas, for example 10-15 pm, 15-20 pm and 20-25 pm, are marked on the steel sheet for the basecoat film thickness wedge. The determination or assessment of the course depending on the layer thickness is carried out with the aid of the Wave scan measuring device from Byk-Gardner GmbH within the previously determined basecoat layer thickness ranges. For this purpose, a laser beam is directed at an angle of 60 ° onto the surface to be examined, and the fluctuations of the reflected light in the so-called short wave range (0.3 to 1.2 mm) and in the so-called iong wave range (1, 2 to 12 mm) registered with the aid of the measuring device (long wave = LW; short wave = SW; the lower the values, the better the appearance). In addition, the measure "sharpness of image" (DOI) is determined as a measure of the sharpness of an image reflected in the surface of the multilayer structure (the higher the value, the better the appearance). 7, determination of cloudiness

To determine the cloudiness, multi-layer coatings are produced according to the following general instructions:

A waterborne basecoat is applied to a steel sheet with the dimensions 32 x 60 cm coated with a conventional filler paint by double application: the application in the first step is electrostatic with a target layer thickness of 8-9 pm, in the second step is also after a 2-minute flash-off time at room temperature electrostatically applied with a target layer thickness of 4-5 pm. The resulting waterborne basecoat is then dried again after 5 minutes at room temperature (18 to 23 ° C) in a forced air oven at 80 ° C for 5 minutes. Both basecoats are applied at a speed of 43,000 rpm and a flow rate of 300 ml / min. A commercially available two-component clear lacquer (ProGloss from BASF Coatings GmbH) with a target layer thickness of 40-45 pm is applied to the dried water-based lacquer layer. The resulting clear lacquer layer is flashed off at room temperature (18 to 23 ° C.) for 10 minutes; Then the curing takes place in a convection oven at 140 ° C for a further 20 minutes.

The cloudiness is then assessed using the cloud-runner measuring device from BYK-Gardner GmbH in accordance with alternative b). Among other things, the device the three parameters "MottlingiS", "Mottl ing45" and "Mottling60", which can be viewed as a measure of the cloudiness, measured at angles of 15 °, 45 ° and 60 ° relative to the angle of reflection of the light source used for the measurement. The larger the value, the more pronounced the cloudy picture.

8. Assessment of streakiness

The streak is assessed using the method described in patent specification DE 10 2009 050 075 B4. The homogeneity indices b and the mean homogeneity index mentioned and defined therein can likewise detect the occurrence of streaks during application, even if these indices were used in the patent specification mentioned to assess the cloudiness are. The higher the corresponding values, the more pronounced stripes can be seen on the substrate, i. Determination of the particle size distribution including the pin value and the

Ratio of the parameters TTI / TT ^ H and TT TT ^ I? as a measure of that

Homogeneity of the spray formed during atomization by means of the method according to the invention

The underlying particle size distributions are determined using a commercial single PDA from DantecDynamics (P60, Lexel Argon iaser, FibreFlow) and a commercial time shift measuring device from AOM Systems (SpraySpy®). Both devices are built and aligned according to the manufacturer's instructions. The settings for the SpraySpy® time-shift measuring device have been adjusted by the manufacturer for the range of materials to be used. The PDA is operated in forward scatter at an angle of 60-70 ^® with a wavelength of 514.5 nm (orthogonally polarized) in reflection. The receiving optics have a focal length of 500 mm, the transmitting optics have a focal length of 400 mm. For both systems, the structure is aligned relative to the atomizer. The general structure is shown in FIG. 1. In Hg. 1, a rotary atomizer has been used as an example. The measurement is carried out traversing in the radial-axial direction in relation to the tilted atomizer (tilt angle 45 °), 25 mm vertically below the atomizer flank inclined to the traversing axis. Here, a defined traversing speed is specified so that the individual detected events are spatially resolved via the associated time-resolved signals. A comparison with grid-resolved measurements provides identical results for the weighted global distribution parameters, but still enables the investigation of any interval ranges on the traversing axis. Furthermore, this method is many times faster than screening, which means that the material expenditure can be reduced with constant flow rates. Detectable drops are recorded with maximum validation tolerance. The raw data are then evaluated using an algorithm for any tolerances. A tolerance of approx. 10% for the PDA system used limits the validation to spherical particles; an increase also includes slightly deformed drops. In this way, an examination of the sphericity of the measured Allows drops along the measurement axis. The SprayS py® system is able to distinguish between transparent and non-transparent drops. The measuring axis (see figure according to FIG. 1) is traversed repeatedly and both measuring methods are used. A double measurement of the individual events is prevented by the system-internal evaluation. The data obtained in this way can thus be evaluated for the transparent spectrum (T) and the non-transparent spectrum (NT). The ratio of the number of measured drops of both spectra serves as a measure for the local distribution of transparent and non-transparent drops. An integral view along the measurement axis is possible. In particular, the ratio of the transparent particles (T) to the total number of particles (total) is determined at a position 1 of x = 5 mm and at a position 2 of x = 25 mm along the measurement axis; the corresponding values are in turn put in relation to describe the homogeneity of the spray which changes from the inside out. For both systems, Single-PDA and SpraySpy®, common distribution moments such as D-io values can be determined based on the raw data.

10- Determination of the solubility of the monomers of the mixture fA) in water, which can be used for the preparation of SCS polymers

The solubility of the monomers in water is determined by equilibrium with the gas space above the aqueous phase (analogous to the literature X.- S. Chai, QX Hou, FJ Schork, Journal of Applied Polymer Science Vol. 99, 1296-1301 (2006) ). For this purpose, a mass of the respective monomer is added to a defined volume of water such as 2 ml in a 20 ml gas space sample tube that this mass cannot dissolve completely in the selected volume of water. In addition, an emulsifier (10 ppm, based on the total mass of the sample mixture) is added. In order to maintain the equilibrium concentration, the mixture is shaken constantly. The protruding gas phase is exchanged for inert gas, so that an equilibrium is restored. The proportion of the substance to be detected is measured in each case in the gas phase removed (for example by means of gas chromatography). The equilibrium concentration in water can be determined by graphically evaluating the proportion of the monomer in the gas phase. The slope of the curve changes from an almost constant value (S1) to a significantly negative value Slope (S2) as soon as the excess monomer was removed from the mixture. The equilibrium concentration is reached at the intersection of the straight line with the slope 61 and the straight line with the slope S2. The determination described is carried out at 25 ° C.

11. Determination of glass transition temperatures of polymers which are each obtainable from monomers of the mixtures (Al (B) or (C)

The glass transition temperature T _g is determined experimentally in accordance with DIN 51005 (date: August 2005) "thermal analysis (TA) - terms" and DIN 53765 "thermal analysis - dynamic differential calorimetry (DDK)" (date: March 1994). A sample is determined of 15 mg weighed into a sample pan and inserted into a DSC device. It is cooled to the start temperature and then a 1. and a second measuring run with an inert gas purging (N ₂ ) of 50 ml / min with a heating rate of 10 K / min, cooling between the measuring runs back to the starting temperature. The measurement takes place in the temperature range from about 50 ° C lower than the expected glass transition temperature to about 50 ° C higher than the expected glass transition temperature. According to DIN 53765, point 8.1, the glass transition temperature is the temperature in the second measuring run at which half the change in the specific heat capacity (0.5 delta cp) is reached. It is determined from the DDK diagram (plot of the heat flow against the temperature). It is the temperature that corresponds to the intersection of the center line between the extrapolated baselines before and after the glass transition with the measurement curve. The well-known Fox equation can be used for a targeted estimate of the glass transition temperature to be expected during the measurement. Since the Fox equation is a good approximation, which is based on the glass transition temperatures of the homopolymers and their weight parts without inclusion of the molecular weight, it can be used as a useful tool for the person skilled in the synthesis, so that a desired glass transition temperature can be set in a few targeted experiments , 12. Determination of the degree of nit

The wetness level of a film formed after application of a coating composition such as a waterborne basecoat to a substrate is assessed. The coating composition is applied electrostatically as a constant layer in the desired target layer thickness (layer thickness of the dried material) such as a target layer thickness which is in a range from 15 pm to 40 m, by means of rotary atomization. The outflow rate is between 300 and 400 ml / min and the rotational speed of the ESTA bell of the rotary atomizer is in a range from 23,000 to 83,000 rpm (the precise details of the application parameters selected in each case are given at the relevant points below within the experimental part ) indicated. One minute after the job is completed, the film formed on the substrate is visually assessed for its degree of wetness. This is recorded on a scale from 1 to 5 (1 = very dry to 5 = very wet).

13- Determining the appearance of stoves

To determine the tendency to cook, a multi-layer coating is produced in accordance with DIN EN ISO 28199-1 (date: January 2010) and DIN EN ISO 28199-3 (date: January 2010) according to the following general rule: one with a hardened cathodic electrocoat (KTL ) (CathoGuard® 800 from BASF Coatings GmbH) coated perforated sheet of 57 cm x 20 cm made of steel (according to DIN EN ISO 28199-1, point 8.1, version A) is analogous to DIN EN ISO 28199-1, point 8.2 (version A) prepared. Then, in accordance with DIN EN ISO 28199-1, point 8.3, the application of an aqueous basecoat is carried out electrostatically in a single application as a wedge with a target layer thickness (layer thickness of the dried material; rock layer thickness) in the range from 0 pm to 30 pm. The resulting basecoat is dried in the forced air oven for 5 minutes at 80 ° C without prior flashing off. The determination of the cooker limit, ie the basecoat layer thickness from which the cooker appears, is carried out according to DIN EN ISO 28199-3, point 5. 14. Determination of the appearance of runners

To determine the inclination of the barrel, multi-layer coatings are produced in accordance with DIN EN ISO 28199-1 (date: January 2010) and DIN EN ISO 28199-3 (date: January 2010) according to the following general regulation: a) Water-based paints

A perforated plate with the dimensions 57 cm x 20 cm made of steel (according to DIN EN ISO 28199-1, point 8.1, version A) coated with a hardened cathodic electrocoat (KTL) (CathoGuard® 800 from BASF Coatings GmbH) becomes analogous to DIN EN ISO 28199-1, point 8.2 (version A) prepared. Then, in accordance with DIN EN ISO 28199-1, point 8.3, an aqueous basecoat is applied electrostatically in a single application as a wedge with a target layer thickness (layer thickness of the dried material) in the range from 0 pm to 40 pm. The resulting basecoat film is dried in a forced air oven for 5 minutes at 80 ° C after a flash-off time of 18 minutes at 18-23 ° C. The sheets are ventilated standing upright and dried in between. b) clear coats:

One with a hardened cathodic electrocoat (KTL) (CathoGuard®

800 from BASF Coatings GmbH) and perforated sheet with dimensions of 57 cm x 20 cm made of steel (according to DIN EN ISO 28199-1, point 8.1, version A) coated with a commercially available water-based paint (ColorBrite from BASF Coatings GmbH) is made analogous to DIN EN ISO 28199-1, point 8.2 (version A) prepared. Then, in accordance with DIN EN ISO 28199-1, point 8.3, a clear coat is applied electrostatically in a single application as a wedge with a target layer thickness (layer thickness of the dried material) in the range from 0 pm to 60 pm. The resulting clear coat is cured after a flash-off time of 18 minutes at 18-23X for 10 minutes in a forced air oven for 20 minutes at 140 ° C. The sheets are flashed off and hardened standing upright.

The inclination of the rotor is determined in accordance with DIN EN ISO 28199-3, point 4. In addition to the layer thickness at which a runner is 10 mm from the lower edge of the hole, the layer thickness is determined from which a first inclination to run on a hole can be visually observed.

15, determination of the opacity

The opacity is determined in accordance with DIN EN ISO 28199-3 (January 2010; point 7).

Examples and comparative examples

The following examples and comparative examples serve to explain the invention, but are not to be interpreted as restrictive.

Unless stated otherwise, the parts are parts by weight and percentages are percentages by weight.

1, preparation of an aqueous dispersion AD1

1.1 The components mentioned below and used to produce the aqueous dispersion AD1 have the following meanings:

DMEA dimethylethanolamine

Deionized water

EF 800 Aerosol® EF-800, commercially available emulsifier from

Cytec company

APS ammonium peroxodisulfate

1,6-HDDA 1,6-hexanediol diacrylate

2-HEA 2-hydroxyethyl acrylate

MMA methyl methacrylate

1.2 Preparation of the aqueous dispersion AD1 containing a multistage SCS polyacrylate

Monomer mixture fAl stage i.

80% by weight of items 1 and 2 according to Table 1.1 below are placed in a steel reactor (5 L volume) with a reflux condenser and heated to 80.degree. The remaining portions of the components listed under “Template” in Table 1.1 are premixed in a separate vessel. This mixture and the initiator solution separated therefrom (Table 1.1, positions 5 and 6) are simultaneously added dropwise to the reactor within 20 min, with a proportion of the monomers in the reaction solution, based on the total amount of in step i. used Monomers, of 6.0 wt .-% is not exceeded during the entire reaction period. The mixture is then stirred for 30 minutes.

Monomer mixture (Bi stage ii.

The components specified under “Mono” in Table 1.1 are premixed in a separate vessel. This mixture is added dropwise to the reactor over the course of 2 hours, with a proportion of the monomers in the reaction solution, based on the total amount of stage ii. monomers used, of 6.0 wt .-% is not exceeded during the entire reaction period. The mixture is then stirred for 1 hour.

Monomer mixture (Ci stage iii.

The components specified in table 1.1 under "Mono 2" are premixed in a separate vessel. This mixture is added dropwise to the reactor over the course of 1 hour, with a proportion of the monomers in the reaction solution, based on the total amount in stage iii. monomers used, of 6.0 wt .-% is not exceeded during the entire reaction period. The mixture is then stirred for 2 hours.

The reaction mixture is then cooled to 60 ° C. and the neutralization mixture (table 1.1, positions 20, 21 and 22) is premixed in a separate vessel. The neutralization mixture is added dropwise to the reactor over the course of 40 min, the pH of the reaction solution being brought to a pH of

7.5 to 8.5 is set. The reaction product is then stirred for a further 30 min, cooled to 25 ° C. and filtered.

The solids content of the aqueous dispersion AD1 thus obtained was determined for the reaction control. The result, together with the pH value and the determined particle size, is given in Table 1.2. Table 1.1: Aqueous dispersion AD1 containing a multi-stage polyacrylate

Table 1.2: Key figures of the aqueous dispersion AD1 and the one containing it

polymer

2. Preparation of an aqueous polyurethane-polyurethane urea dispersion PD1

Manufacture of a partially neutralized prepolymer solution

559.7 parts by weight of a linear polyester polyol and 27.2 parts by weight of dimethylolpropionic acid (from GEO Specialty Chemicals) were dissolved in 344.5 parts by weight of methyl ethyl ketone under nitrogen in a reaction vessel equipped with a stirrer, internal thermometer, reflux condenser and electrical heating. The linear polyester diol was previously prepared from dimerized fatty acid (Pripol® 1012, from Croda), isophthalic acid (from BP Chemicals) and hexane-1,6-diol (from BASF SE) (weight ratio of the starting materials: dimeric fatty acid to isophthalic acid too Hexane-1, 6-diol = 54.00: 30.02: 15.98) and had a hydroxyl number of 73 mg KOH / g solids, an acid number of 3.5 mg KOH lg solids and a calculated number average molecular weight of 1379 g / mol and a number average molecular weight of 1350 g / mol determined by vapor pressure osmometry. 213.2 parts by weight of dicyclohexylmethane-4,4'-diisocyanate (Desmodur® W, from Covestro AG) with an isocyanate content of 32.0% by weight and 3.8% by weight of dibutyltin dilaurate ( Merck) added. The mixture was then heated to 80 ° C. with stirring. The stirring was continued at this temperature until the isocyanate content of the solution was 1.49% by weight and was constant. Thereafter, 626.2 parts by weight of methyl ethyl ketone were added to the prepolymer and the reaction mixture was cooled to 40 ° C. After 40 ° C. had been reached, 11.8 parts by weight of triethylamine (from BASF SE) were added dropwise in the course of two minutes and the mixture was stirred for a further 5 minutes.

Implementation of the prepolymer with diethylenediamine diketimine

Subsequently, 30.2 parts by weight of a 71.9% by weight solution of diethylene triaminediketimine in methyl isobutyl ketone (ratio of isocyanate groups of the prepolymer to diethylenetriaminediketimine (with a secondary amino group): 5: 1 mol / mol, corresponds to two NCO groups per blocked , primary amino group) mixed in within one minute, the reaction temperature rising briefly after addition to the prepolymer solution by 1 ° C. The dissolution of diethylenetriamine diketimine in methyl isobutyl ketone was previously by azeotnopes circles of water of reaction in the reaction of diethylenetriamine (BASF SE) with methyl isobutyl ketone in methyl isobutyl ketone at 110 - 140 ° C. The mixture was adjusted to an amine equivalent mass (solution) of 124.0 g / eq by dilution with methyl isobutyl ketone. A blocking of the primary amino groups of 98.5% was determined by means of IR spectroscopy based on the residual absorption at 3310 cm-1. The solids content of the isocyanate group-containing polymer solution was determined to be 45.3%.

Dispersion and vacuum distillation

After stirring at 40 ° C for 30 minutes, the contents of the reactor were dispersed in 1206 parts by weight of deionized water (23 ° C) within 7 minutes. Methyl ethyl ketone was distilled off from the resulting dispersion at 45 ° C. under vacuum and any solvent and water losses were compensated for with deionized water, so that a solids content of 40% by weight resulted. A white, stable, high-solids, low-viscosity dispersion with crosslinked particles was obtained which did not show any settling even after 3 months. The microgel dispersion (PD1) thus obtained had the following key figures:

Solids content (130 ° C, 60 min, 1 g): 40.2% by weight

Methyl ethyl ketone content (GC): 0.2% by weight

Methyl isobutyl ketone content (GC): 0.1% by weight

Viscosity (23 ° C, rotational viscometer, shear rate = 1000 / s): 15 mPa-s

Acid number: 17.1 mg KOH / g

Solids content

Degree of neutralization (calculated): 49%

pH (23 ° C): 7.4

Particle size (photon correlation spectroscopy,

Volume average): 167 nm

Gel fraction (freeze-dried): 85.1% by weight

Gel content (130 ° C): 87.3% by weight 3, production of Fe d filler pastes

3.1 Production of a gum paste P1

The yellow paste P1 is made from 17.3 parts by weight of Sieotrans yellow L 1916, available from BASF SE, 18.3 parts by weight of a polyester produced according to Example D, column 16, lines 37-59 of DE 40 09 858 A1, 43.6 parts by weight one prepared according to international patent application WO 92/15405, page 15, lines 23-28

Binder dispersion, 16.5 parts by weight of deionized water and 4.3 parts by weight of butyl glycol.

3.2 Production of a white paste P2

The white paste P2 is made from 50 parts by weight of titanium rutile 2310, 6 parts by weight of a polyester produced according to Example D, column 16, lines 37-59 of DE 40 09 858 A1, 24.7 parts by weight of one according to the patent application EP 022 8003 B2, p. 8, line 6 to 18 prepared binder dispersion, 10.5 parts by weight of deionized water, 4 parts by weight of 2,4,7,9-tetramethyl-5-decindiol, 52% in BG (available from BASF SE), 4.1 parts by weight of butyl glycol , 0.4 part by weight of 10% dimethylethanolamine in water and 0.3 part by weight of Acrysol RM-8 (available from The Dow Chemical Company).

3.3 Production of a black paste P3

The black paste P3 is made from 57 parts by weight of a polyurethane dispersion prepared in accordance with WO 92/15405, page 13, line 13 to page 15, line 13, 10 parts by weight of carbon black (carbon black Monarch® 1400 from Cabot Corporation), 5 parts by weight of a polyester , prepared according to Example D, column 16, lines 37-59 of DE 40 09 858 A1, 6.5 parts by weight of a 10% aqueous dimethylethanolamine solution, 2.5 parts by weight of a commercially available polyether (Pluriol® P900, available from BASF SE ), 7 parts by weight of butyl diglycol and 12 parts by weight of deionized water

3.4 Production of a barium sulfate paste P4

The barium sulfate paste P4 is made from 39 parts by weight of a polyurethane dispersion prepared in accordance with EP 0228003 B2, page 8, lines 6 to 18, 54 parts by weight of barium sulfate (Blanc fixe micro from Sachtleben Chemie GmbH), 3.7 parts by weight of butyl glycol and 0.3 parts by weight of Agitan 282 (available from Munzing Chemie GmbH) and 3 parts by weight of deionized water.

3.5 Production of a steatite paste PS

The steatite paste P5 is made from 49.7 parts by weight of an aqueous binder dispersion prepared according to WO 91/15528, page 23, line 26 to page 24, line 24, 28.9 parts by weight of steatite (Microtalc IT extra from Mondo Minerals BV) , 0.4 parts by weight of Agitan 282 (available from Munzing Chemie GmbH), 1.45 parts by weight of Disperbyk®- 184 (available from BYK-Chemie GmbH), 3.1 parts by weight of a commercially available polyether (Pluriol® P900, available from BASF SE) and 16.45 parts by weight of deionized water.

4. Production of further intermediates

4.1 Production of a mixed lacquer ML 1

Based on the patent specification EP 1534792-B1, column 11, lines 1-13, 81.9 parts by weight of deionized water, 2.7 parts by weight of Rheovis® AS 1 130 (available from BASF SE), 8.9 parts by weight of 2.4, 7,9-tetramethyl-5-decindiol, 52% in BG (available from BASF SE), 3.2 parts by weight of Dispex Ultra FA 4437 (available from BASF SE) and 3.3 parts by weight of 10% dimethylethanolamine mixed in water; the resulting mixture is then homogenized.

4.2 Production of a mixed lacquer ML2

47.38 parts by weight of the aqueous dispersion AD1, 42.29 parts by weight of deionized water, 6.05 parts by weight of 2,4,7,9-tetramethyl-5-decindiol, 52% in butylglycol (available from BASF SE), 2.52 parts by weight Dispex Ultra FA 4437 (available from BASF SE), 0.76 part by weight of Rheovis® AS 1 130 (available from BASF SE) and 1.0 part by weight of 10% dimethylethanolamine in water are mixed together and the resulting mixture is then homogenized.

ML1 and ML2 are used to produce effect pigment pastes. 5. Production of aqueous basecoats

5.1 Production of water-based paints WBL1 and WBL2

The components listed in Table 5.1 under "aqueous phase" are stirred together in the order given to form an aqueous mixture. In the next step, the under. aluminum pigment premix ”or“ micapigment premix ”components. These premixes are added separately to the aqueous mixture. After adding a premix, the mixture is stirred for 10 minutes in each case. Then, using deionized water and dimethylethanolamine, a pH of 8 and a spray viscosity of 95 ± 10 mPa-s at a shear stress of 1000 s ^{' 1} , measured with a rotary viscometer (Rheolab GG device with temperature control system C-LTD80 / GC from Anton Paar) at 23 ° C.

Table 5.1: Production of the water-based paints WBL1 and WBL2

WBL1 WBL2

Aqueous phase:

3% Na-Mg layered silicate solution 14.4 13.4 deionized water 11.5 11.4

1-propoxs-2-propanol 2.4

n-butoxy propanol 1.9 1.1

2-ethylhexanol 2.8

Aqueous binder dispersion AD1 22.6

Aqueous polyurethane-polyurethane dispersion PD1 6.6

Polyurethane dispersion, produced according to WO 92/15405, p. 13, line.

29.3

13 to p. 15, line 13

Polyester; produced according to page 28, lines 13 to 33 (example

1.5

BE1) WO 2014/033135 A2 ^3.8

Polyester; prepared according to Example D, column 16, lines 37-59 of DE

2.2

40 09 858 A1

Polyurethane modified polyacrylate; produced according to p. 7, line 55

2.2 to 5.8, line 23 of DE 4437535 A1

Melamine formaldehyde resin (Cymel® 203 from Alfnex) 2.8

Melamine formaldehyde resin (Maprenal® 909 93IB from INEOS

3.3 Melamines GmbH)

10% dimethylethanolamine in water 0.7 1.0

Pluriol® P900, available from BASF SE 0.6

2,4,7,9-tetramethyl-5-decindiol, 52% in BG (available from BASF

0.2 SE)

Isobutanol 3.1

Isopropanol 1.8

Butyl glycol 1.1 2.6

Hydrosol A170, available from DHC Solvent Chemie GmbH 0.4 methoxypropanol 2.0

Isopar® L, available from Exxon Mobil 1.5

50% by weight solution of Rheovis® PU1250 in butyl glycol

0.3

(Rheovis® PU 1250 available from BASF SE)

BYK-347® from Altana / BYK-Chemie GmbH 0.4

Yellow paste P1 1.7 1.7

White paste P2 0.7 0.7

Black paste P3 3.4 3.4

Barium sulfate paste P4 0.7 0.7

Steatite paste P5 1, 4 1.4 Aluminum pigment premix:

Mixing lacquer ML1 12.2 12.2

Mixture of two commercially available aluminum pigments, available

from Altana-Eckart (Stapa® Hydrolux 2153 & Hydrolux 600 in 4.0 4.0

Ratio 1: 1)

Mlcapigment premix:

Mixed varnish L1 1.0 1.0

Commercially available micapigment Mearlin® Exterior Fine Russet 459V

from BASF SE) ^{ül4 0.6}

Total: 100.0 100.0

Ratio pigment / binder: 0.3 0.3

Solid (discontinued): 21.6% 21.7%

5.2 Production of waterborne basecoats WBL3 to WBL6

The components listed in Table 5.2 under "aqueous phase" are mixed together in the order given to form an aqueous mixture. In the next step, a premix is made from the components listed under "Aluminum pigment premix". This premix is added to the aqueous mixture. After the addition, the mixture is stirred for 10 minutes. Then, using deionized water and dimethylethanolamine, a pH of 8 and a spray viscosity of 85 ± 5 mPa-s at a shear stress of 1000 s ¹ , measured using a rotary viscometer (Rheolab QC device with temperature control system C-LTD80 / QG from Anton Paar) at 23 ° C.

Within the WBL3 to WBL4 series, the proportion of aluminum pigment and thus the pigment / binder ratio have been reduced. The same applies to the WBL5 to WBL6 series. Table 5.2: Production of waterborne basecoats WBL3 to WBL6

Aqueous phase;

3% Na-Mg layered silicate solution 17.87 17.87 17.87 17.87 deionized water 12.23 16.74 12.07 16.68 2-ethylhexano! 1, 99 1, 99 1, 99 1, 99

Polyurethane dispersion, manufactured according to WO

25.41 25.41 25.41 25.41 92/15405, p. 13, line 13 to p. 15, line, 13

Daotan® VTW 6464, available from Allnex 1, 59 1, 59 1.59 1.59

Polyurethane modified polyacrylate; manufactured

according to S, 7, line 55 to page 8, line 23 of DE 4437535 2.78 2.78 2.78 2.78

A1

3% by weight aqueous Rheovis® AS 1130

Solution, Rheovis® AS 1130 available from BASF 5.08 5.08 5.08 5.08

SE

Melamine formaldehyde resin {Cymel® 1133 der

3.57 3.57 3.57 3.57 company Allnex)

10% dimethylethanolamine in water 0.95 0.95 0.95 0.95 Pluriol® P900, available from BASF SE 0.40 0.40 0.40 0.40

2,4,7,9-tetramethyl-5-deci rtd iol, 52% in BG

1.35 1.35 1.35 1.35 (available from BASF SE)

Triisobutyl phosphate 1, 19 1, 19 1.19 1, 19

Isopropanol 1, 95 1, 95 1.95 1, 95

Butylglyko! 2.54 2.54 2.54 2.54

50% by weight solution of Rheovis® PU1250 in

Butylglyko! (Rheovis® PU 1250 available from 0.24 0.24 0.24 0.24

BASF SE)

Tinuvin® 123, available from BASF SE 0.64 0.64 0.64 0.64 Tinuvin® 384-2, available from BASF SE 0.40 0.40 0.40 0.40

Aluminiumplgment premix:

Aluminum pigment Stapa® Hydrolux 600,

7.22 2.71

available from Altana-Eckart

Aluminum pigment Stapa® Hydrolux 200,

7.38 2.77 available from Altana-Eckart

Butyl glycol 9.60 9.60 9.60 9.60

Polyester: produced according to Example D, column

3.00 3.00 3.00 16, lines 37-59 of DE 40 09 858 A1

Total: 100.00 100.00 100.00 100.00

Ratio pigment / binder: 0.35 0.13 0.35 0.13 5.3 Production of waterborne basecoats WBL7 to WBL10

The components listed in Table 5.3 under "aqueous phase" are stirred together in the order given to form an aqueous mixture. In the next step, a premix is made from the components listed under "Aluminum pigment premix". This premix is added to the aqueous mixture. After the addition, the mixture is stirred for 10 minutes. Subsequently, with the aid of deionized water and dimethylethanolamine, a pH of 8 and a spray viscosity of 85 ± 5 mPa-s at a shear stress of 1000 s ¹ _»is measured using a rotary viscometer (Rheolab QC device with temperature control system C-LTD80 / QC from Anton Paar) at 23 ° C.

Within the WBL7 to WBL8 series, the proportion of aluminum pigment and thus the pigment / binder ratio have been reduced. The same applies to the WBL9 to WBL10 series.

Table 5.3: Production of water-based paints WBL7 to WBL10

Aqueous phase:

3% Na-Mg layered silica solution 14.45 14.45 14.45 14.45 deionized water 8.99 13.50 8.83 13.44

2-ethylhexanol 1, 91 1.91 1, 91 1, 91

Aqueous binder dispersion AD1 26.33 26.33 26.33 26.33

Aqueous polyurethane-polyurea dispersion PD1 6.09 6.09 6.09 6.09

Polyester; produced according to page 28, lines 13 to 33

3.01 3.01 3.01 3.01 (example BE1) WO 2014/033135 A2

Melamine formaldehyde resin (Cymel® 203 from the company

6.67 6.67 6.67 6.67 Allnex)

deionized water 1, 69 1.69 1, 69 1, 69

Rheovis® AS 1130, available from BASF SE 0.22 0.22 0.22 0.22 10% dimethylethanolamine in water 0.51 0.51 0.51 0.51

2,4,7,9-tetramethyl-5-decindioS, 52% in BG (available

0.29 0.29 0.29 0.29 from BASF SE)

But glycof 3.89 3.89 3.89 3.89

50% by weight solution of Rheovis® PU 1250 in

0.07 0.07 0.07 0.07 butyl glycol (Rheovis® PU 1250 available from BASF SE)

Aiuminiumplgment premix:

Mixing varnish ML2 18.66 18.66 18.66 18.66

Aluminum pigment Stapa® Hydrolux 600, available from ^ ^

2.71

Altana-Eckart company

Aluminum pigment Stapa® Hydrolux 200, available from

7.38 2.77 from Altana-Eckart

Total: 100.00 100.00 100.00 100.00

Pigment / binder ratio: 0.25 0.09 0.25 0.09 5.4 Production of water-based paints WBL17 to WBL24, WBL17a and WBL21a

The components listed in Table 5.4 under "aqueous phase" are stirred together in the order given to form an aqueous mixture. In the next step, the under. aluminum pigment premix “components produced a premix. This premix is added to the aqueous mixture. After the addition, the mixture is stirred for 10 minutes. Then, using deionized water and dimethylethanolamine, a pH of 8 and a spray viscosity of 85 ± 5 mPa-s at a shear stress of 1000 s ¹ , measured using a rotary viscometer (Rheolab QC device with temperature control system C-LTD80 / QC from Anton Paar) at 23 ° C.

In addition, the samples WBL17 and WBL21 were tested for a spray viscosity of 120 ± 5 mPa-s at a shear stress of 1000 s ¹ using a rotary viscometer (Rheolab QC device with temperature control system C-LTD80 / QC or

Anton Paar) set at 23 ° C (resulting in WBL17a or WBL21a).

Table 5.4: Production of waterborne basecoats WBL17 to WBL24

Aqueous phase:

3% Na-Mg

17.87 17.87 17.87 17.87 17.87 17.87 17.87 17.87 layered silicate solution

deionized water 11.45 12.07 16.45 16.68 11.61 12.07 16.51 16.68 2-ethylhexanof 1.99 1.99 1.99 1.99 1.99 1.99 1.99 1.99 polyurethane dispersion,

manufactured according to WO

25.41 25.41 25.41 25.41 25.41 25.41 25.41 25.41 92/15405, p.13, Z.13 to p.

15, line 13

Daotan®VTW6464,

1.59 1.59 1.59 1.59 1.59 1.59 1.59 1.59 available from Allnex

Polyurethane adhesive

polyacrylate; manufactured

2.78 2.78 2.78 2.78 2.78 2.78 2.78 2.78 according to page 7, line 55 to page 8, line.

23 of DE 4437535 A1

3% by weight aqueous

Rheovis® AS 1130 solution,

5.08 5.08 5.08 5.08 5.08 5.08 5.08 5.08 Rheovis® AS 1130 available

from BASF SE

Melamine formaldehyde resin

(Cymel® 1133 from 3.57 3.57 3.57 3.57 3.57 3.57 3.57 3.57 Allnex)

10%

Dimethylethanolamine in 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95

water

Pluriol® P900, available from

0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40

BASF SE

2,4,7,9-tetramethyl-5-decindiof, 52% in BG 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 (available from BASF SE)

Triisobutyl phosphate 1.19 1.19 1.19 1.19 1.19 1.19 1.19 1.19

Isopropanol 1.95 1.95 1.95 1.95 1.95 1.95 1.95 1.95

Butyiglykoi 2.54 2.54 2.54 2.54 2.54 2.54 2.54 2.54

50% by weight solution of

Rheovis® PU 1250 in

Butyiglykoi (Rheovis® 0.24 0.24 0.24 0.24 0.24 0.24 0.24 0.24

PU 1250 available from BASF

SE)

Tinuvin® 123 available from

0.64 0.64 0.64 0.64 0.64 0.64 0.64 0.64

BASF SE

Tinuvin® 384-2, available from

0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40

BASF SE

Aluminum pigment Stapa® IL

HYDROLAN 9157, available 8.00 3.00

from Altana-Eckart

Aluminum pigment Stapa® IL

HYDROLAN 214 N0.55,

7.38 - 2.77

available from Altana-Eckart

Aluminum pigment Stapa® IL

HYDROLAN 2197, available from 7.84 to 2.94 from Altana-Eckart

Aluminum pigment Stapa® IL

HYDROLAN 2153, available - 7.38 - 2.77 from Altana-Eckart

Butyl glycol 9.60 9.60 9.60 9.60 9.60 9.60 9.60 9.60

Polyester; manufactured according to

Example D, column 16, lines 37-3.00 3.00 3.00 3.00 3.00 3.00 3.00 3.00

59 of DE 4009858 Ai

Total: 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00

relationship

0.35 0.13 0.35 0.13 0.35 0.13 0.35 0.13

Pigment / Binder:

5.5 Production of waterborne basecoats WBL25 to WBL30

The components listed in Table 5.5 under "aqueous phase" are mixed together in the order given to form an aqueous mixture. In the next step, a premix is made from the components listed under "Aluminum pigment premix". These premixes are added separately to the aqueous mixture. After adding a premix, the mixture is stirred for 10 minutes in each case. Subsequently, with the aid of deionized water and dimethylethanolamine, a pH of 8 and a spray viscosity of 85 ± 10 mPa-s at a shear stress of 1000 s ^' \ are measured using a rotary viscometer (Rheoiab QC device with temperature control system C-LTD80 / QC from Anton Paar) at 23 ° C. Table 5.5: Manufacture of water-based paints WBL25 to WBL30

Aqueous phase:

3% Na-Mg layered silicate solution 14.45 14.45 14.45 14.45 14.45 14.45 deionized water 8.21 8.83 13.21 13.44 8.21 13.21 2-ethylhexanol 1 , 91 1.91 1, 91 1.91 1, 91 1, 91

Aqueous binder dispersion AD1 26.33 26.33 26.33 26.33 26.33 26.33

Aqueous polyurethane-polyurea dispersion

6.09 6.09 6.09 6.09 6.09 6.09

PD1

Polyester: manufactured according to page 28, lines

3.01 3.01 3.01 3.01 3.01 3.01 13 to 33 (example BE1) WO 2014/033135 A2

Melamine formaldehyde resin (Cymel® 203 der

6.67 6.67 6.67 6.67 6.67 6.67 from Allnex)

deionized water 1.69 1.69 1, 69 1, 69 1, 69 1, 69

Rheovis® AS 1130, available from BASF SE 0.22 0.22 0.22 0.22 0.22 0.22 10% dimethylethanolamine in water 0.51 0.51 0.51 0.51 0.51 0, 51

2,4,7,9-T etramethyf-S-decindioi, 52% in BG

0.29 0.29 0.29 0.29 0.29 0.29

{available from BASF SE)

Butyl glycol 3.89 3.89 3.89 3.89 3.89 3.89

50% by weight solution of Rheovis® PU 1250

in butyl glycol (Rheovis® PU 1250 available from 0.07 0.07 0.07 0.07 0.07 0.07 BASF SE)

Aluminum pigment premix:

Mixing varnish ML2 18.66 18.66 18.66 18.66 18.66 18.66

Aluminum pigment Stapa® IL HYDROLAN

8.00 3.00

9157, available from Altana-Eckart

Aluminum pigment Stapa® IL HYDROLAN 214

7.38 2.77

N0.55, available from Altana-Eckart

Aluminum pigment Stapa® HYDROLUX 2197,

8.00 3.00 available from Altana-Eckart

Total: 100.00 100.00 100.00 100.00 100.00 109.00

Pigment / binder ratio: 0.25 0.09 0.25 0.09 0.25 0.09

5.6 Production of waterborne basecoats WBL31 and WBL31a The components listed in table 5.6 under "aqueous phase" are mixed together in the order given to form an aqueous mixture. In the next step, a premix is made from the components listed under "Aluminum pigment premix". This premix is added to the aqueous mixture. After the addition, the mixture is stirred for 10 minutes. Then with With the help of deionized water and dimethylethanolamine to a pH of 8 and a spray viscosity of 130 ± 5 mPa-s (WBL31) or, 80 ± 5 mPa-s (WBL31a) with a shear stress of 1000 s ^' \ measured with a rotation Viscometer (Rheolab QC device with temperature control system C-LTD80 / QC from Anton Paar) set at 23 ° C. In the case of WBL31a, a higher amount of deionized water is used for this.

Table 5.8: Production of the water-based paints WBL31 and WBL31a

Aqueous phase:

3% Na-Mg layered silicate solution 17.00 17.00 deionized water 10.89 10.89

2-ethylhexanol 1.89 1.89

Polyurethane dispersion, prepared according to WO 92/15405, p. 13, line.

24.17 24.17

13 to p. 15, line 13

Daotan® VTW 6464, available from Allnex 1, 51 1.51

Polyurethane modified polyacrylate; stiffened according to p. 7, line 55

2.64 2.64 to p.8, line 23 of DE 4437535 A1

3% by weight aqueous Rheovis® AS 1130 solution, Rheovis® AS

4.83 4.83

1130 available from BASF SE

Melamine formaldehyde resin (Cymel® 1133 from Allnex) 3.40 3.40

10% diethyl ethanolamine in water 0.90 0.90

Pluriol® P900, available from BASF SE 0.38 0.38

2,4,7,9-tetramethyl-5-decindiol, 52% in BG (available from BASF

1.28 1.28

SE)

Triisobutyl phosphate 1.13 1.13

Isopropanol 1.85 1.85

Butyl glycol 2.42 2.42

50% by weight solution of Rheovis® PU1250 in butyl glycol

0.23 0.23

(Rheovis® PU 1250 available from BASF SE)

Tinuvin® 123, available from BASF SE 0.61 0.61

Tinuvin® 384-2, available from BASF SE 0.38 0.38 deionized water 7.91 12.10

Aluminum pigment premix:

Aluminum pigment Stapa® HYDROLUX VP56450, available from

3.26 3.26

Altana-Eckart company

Aluminum pigment Stapa® HYDROLUX 1071, available from the company

1, 30 1, 30

Altana Eckart

Butyl glycol 9.21 9.21

Polyester; prepared according to Example D, column 16, lines 37-59 of DE

2.79 2.79

40 09 858 A1

Total: 100.00 104.19

Ratio pigment / binder: 0.23 0.23 5.7 Production of waterborne basecoats WBL32 and WBL33

The components listed in Table 5.7 under "aqueous phase" are stirred together in the order given to form an aqueous mixture. In the next step, a premix is made from the components listed under "Butyl glycol / polyester mix (3: 1)". This premix is added to the aqueous mixture. After the addition, the mixture is stirred for 10 minutes. Then, using deionized water and dimethylethanolamine, a pH of 8 and a spray viscosity of 135 ± 5 mPa-s at a shear stress of 1000 s ^"1 , measured with a rotary viscometer (Rheolab QC device with temperature control system C-LTD80 / QC from Anton Paar) at 23 ° C.

Table 5.7: Production of the water-based paints WBL32 and WBL33

Aqueous phase:

3% Na-Mg-Schiehsiliatlösung 20.82 20.82

deionized water 13.34 13.34

2-ethylhexanol 2.32 2.32

Polyunethane dispersion, prepared according to WO 92/15405, p. 13, line.

29.60 29.60

13 to p. 15, line 13

Daotan® VTW 6464 available from Allnex 1.85 1.85

Polyurethane modified polyacrylate; produced according to p. 7, line 55

3.24 3.24 to p.8, line 23 of DE 4437535 A1

3% by weight aqueous Rheovis® AS 1130 solution, Rheovis® AS

5.92 5.92

1130 available from BASF SE

Melamine formaldehyde resin (Cymel® 1133 from Allnex) 4.16 4.16

10% dimethylethanolamine in water 1.11 1.11

Plursol® P90Q, available from BASF SE 0.47 0.47

2,4,7,9-tetramethyl-5-decindiol, 52% in BG (available from BASF

1.57 1.57

SE)

Triisobuty Iphosphate 1.39 1.39

Isopropanol 2.27 2.27

Butyl glycol 2.96 2.96

50% by weight solution of Rheovis® PU 1250 in butyl glycol

0.28 0.28

(Rheovis® PU 1250 available from BASF SE)

Tinuvin® 123, available from BASF SE 0.75 0.75

Tinuvin® 384-2, available from BASF SE 0.47 0.47

Butylglycol / polyester blend (3: 1)

Butyl glycol 5.63 9.38

Polyester; prepared according to Example D, column 16, lines 37-59 of DE

1.88 3.13

4009858 A1

Total: 100.00 105.00 5.8 Production of the water-based paints WBL34, WBL35, WBL34a and WBL35a The components listed in table 5.8 under "aqueous phase" are mixed together in the order given to form an aqueous mixture. After stirring for 10 minutes, the pH is then adjusted to 8 with the aid of deionized water and dimethylethanolamine and the spray viscosity is 120 ± 5 mPa-s (WBL34 and WBL35) or 80 ± 5 mPa-s (WBL34a and WBL35a) at a shear stress of 1000 s \ measured with a rotary viscometer (Rheolab QC device with temperature control system C-LTD80 / QC from Anton Paar) at 23 ° C.

Table 5.8: Production of the water-based paints WBL34, WBL34a, WBL35 and WBL35a

Aqueous phase:

3% Na-Mg particulate solution 19.69 19.69 19.69 19.69 deionized water 12.62 12.62 12.62 12.62

2-ethylhexanol 2.19 2.19 2.19 2.19

Polyurethane dispersion, manufactured according to WO

28.00 28.00 28.00 28.00 92/15405, p. 13, line 13 to page 15, line 13

Daotan® VTW 6484, available from Alinex 1.75 1.75 1, 75 1, 75

Polyurethane modified polyacrylate; manufactured

according to page 7, line 55 to page 8, line 23 of DE 4437535 3.06 3.06 3.06 3.06 A1

3% by weight aqueous Rheovis® AS 1 130

Solution, Rheovis® AS 1130 available from BASF 5.60 5.60 5.60 5.60 SE

Melamine formaldehyde resin (Cymel® 1 133 der

3.93 3.93 3.93 3.93 from Alinex)

10% dimethylethanolamine in water 1.05 1.05.05.05.05 Pluriol® P900, available from BASF SE 0.44 0.44 0.44 0.44

2,4,7,9-tetramethyl-5-decindiol, 52% in BG

1, 49 1, 49 1.49 1, 49 (available from BASF SE)

Triisobutyl phosphate 1, 31 1, 31 1.31 1, 31

Isopropanol 2.15 2.15 2.15 2.15

Butyl glycol 2.80 2.80 2.80 2.80

50% by weight solution of Rheovis® PU 1250 in

Butylglycol (Rheovis® PU 1250 available from 0.26 0.26 0.26 0.26

BASF SE)

Tinuvin® 123, available from BASF SE 0.71 0.71 0.71 0.71 Tinuvin® 384-2, available from BASF SE 0.44 0.44 0.44 0.44

Butyl glycol 12.50 - 12.50 deionized water 3.00 3.00

Total: 87.50 100.00 90.50 103.00 6, investigations and comparison of the properties of the aqueous basecoats or the coatings obtained therefrom

6.1 Comparison between the water-based paints. WBL5 and WBL9 with regard to the occurrence of streakiness or the homogeneity of the spray formed during atomization

The tests on the water-based paints WBL5 and WBL9 (these paints each contain identical amounts of the identical aluminum pigment) with regard to streakiness or the homogeneity of the spray are carried out according to the methods described above. Table 6.1 summarizes the results.

Table 6.1: Comparison of streakiness by means of the homogeneity index HS (according to patent specification DE 10 2009 050 075 B4) and the key figures T _T i / T _T otaii, T _T 2 / T _T otai2 or the ratio thereof

The numbers 15 to 110 in connection with the homogeneity index Hl relate to the respectively chosen angle in ⁰ when the measurement is carried out, in which the data to be determined are determined a certain number in ° away from the gloss angle. For example, HI15 means that this Homogeneity index refers to data recorded 15 ° away from the glancing angle.

WBL5 and WBL9 have identical pigmentation, but differ in their basic composition.

The values in Table 8.1 show that the different tendency towards streaking, which is determined using the homogeneity indices according to patent DE 10 2009 050 075 B4, with the ratio of Tn / Tr _o t _a n at x = 5 mm (inside) and re / T-ro _t a _ß x = 25 mm (outside) correlated:

The higher the value of the quotient from T _T1 / Tio _t aii and TT ₂ / TT ₀ M2, the more non-transparent (NT), i.e. (effect) pigment-containing particles from inside take in a spray formed during atomization to the outside. This means that a material is separated more strongly during application into areas with different concentrations of (effect) pigments and is therefore more inhomogeneous or more susceptible to the formation of stripes.

In contrast to methods known from the prior art, such as a time-shift method which measures either only transparent or only non-transparent particles, the method according to the invention for characterizing the atomization includes a differentiation between transparent and non-transparent particles and combines both Information with each other. As shown in the example above, this differentiation and combination is necessary to understand the processes involved in the atomization of pigment-containing paints,

6.2 Comparison between the water-based paints WBL1 and WBL2 with regard to the occurrence of pinholes

The tests on the water-based paints WBL1 and WBL2 with regard to the occurrence of pinholes are carried out according to the method described above. Table 6.2 summarizes the results. Table 6.2 Results of the investigations regarding the occurrence of needlesticks

Outflow rate: 300 ml / min; Speed: 23000 rpm

WBL Dio [pm] needlesticks

WBL1 32.0 0

WBL2 44.3> 100

In comparison to WBL1, WBL2 proved to be significantly more critical with regard to the occurrence of needlesticks. This behavior correlates with a larger value of D-io, which was determined experimentally in the case of WBL2 compared to WBL1 and which in turn is a measure for a coarser atomization or an increased degree of wetness. 6.3 Comparison between the water-based patches WBL3, WBL4, WBL6 to WBLB and WBL10 with regard to the assessment of cloudiness, the occurrence of pinholes and the course depending on the layer thickness

The investigations on the water-based areas WBL3, WBL4, WBL6 to WBL8 and WBLIO with regard to the assessment of cloudiness, pinholes and the course dependent on the layer thickness are carried out according to the methods described above. Tables 6.3 and 6.4 summarize the results.

Table 6.3: Results of the investigations with regard to pinholes and cloudiness (measured with the cloud runner from Byk-Gardner)

Outflow rate: 300 ml / min; Speed: 43000 rpm

WBL Dio [pi nj needles Hoiling15 Mott) ing45 MottlfngSO

WBL3 23.5> 100 3.8 4.2 4.1

WBL4 26.8> 100 2.9 4.4 3.5

BL6 31.5> 100 4.8 4.4 6.3

WBL7 19.1 0 3.3 3.9 3.9

WBL8 15.9 0 2.7 3.8 3.4

WBL10 15.6 0 4.1 4.4 6.1 A direct comparison of the sample pairs WBL3 and WBL7, WBL4 and WBL8, or WBL6 and WBL10, which each contain the same pigment and the same amount of pigment, shows that the basecoats WBL7, WBL8 and WBL10 with an outflow rate of 300 ml / min and a speed of 43,000 rpm each have a smaller D-io value than the corresponding reference sample WBL3, WBL4 and WBL6 and thus atomize more finely. This is reflected in significantly better needlestick robustness and also less cloudiness. Table 6.4: Results of the investigations with regard to the course depending on the layer thickness

Outflow rate: 300 ml / min; Speed: 43000 rpm

10-15 mpi 15-20 mpi 20-25 pm

WBL DIQ Ipm] SW DOI SW DOI SW DOI

WBL3 23.5 11.5 77.3 16.1 72.2 17.2 71.6

WBL5 30.1 14.7 64.6 19.9 63.8 24.0 60.8

WBL4 26.8 8.60 85.05 11.90 83.82 14.30 82.73

WBL6 31.5 10.40 74.35 15.10 71, 44 18.70 68.37

WBL3 and WBL5 each have a pigment / binder ratio of 0.35, whereas WBL4 and WBL6 each have a pigment / binder ratio of 0.13.

The experimental results show a correlation between the D ₁₀ values or the resulting atomization properties and the appearance / course, here depending on the layer thickness: When comparing the samples with an identical pigment / binder ratio of 0.35 (WBL3 and WBL5 ) or 0.13 (WBL4 and WBL6) shows that a larger D ₁₀ value, i.e. a coarser and therefore wetter atomization leads to poorer historical values, which is illustrated by the short wave and DOI values obtained. 6.4 Comparison between the waterborne basecoats WBL3 to WBL10 to WBL17 to WBL20 and WBL25 to WBL28 with regard to opacity, cloud tendency, pinpricks and flow (influence of pigment) and course were done according to the methods described above. In particular, it clarifies how the atomization and the resulting coating properties can be influenced by replacing the aluminum pigment used, in particular with regard to its grain size. The outflow rate in all experiments was 300 ml / min; the speed of the ESTA bell was 43,000 rpm. Tables 6.5 to 6.9 summarize the results.

Table 6.5: Results of the investigations with regard to opacity, cloudiness (visual evaluation) and pinpricks

Aluminum pigment

Nadel¬

WBL Muphologie Deckver¬

clouds

like [pm] stitches

WBL17 Comfiake 19 fine 0.35 24.8 9 2-3 90

WBL18 Comfiake 34 coarse 0.35 33.2 11 34 130

WBL19 Comfiake 19 fine 0.13 29.0 14 3 120

WBL20 Comfiake 34 coarse 0.13 33.3 16 3-4 160

¹¹ Key figures according to the technical data sheet from Eckart

p / b = pigment-binder ratio Table 6.6: Results of the investigations regarding hiding power, cloudiness

(visual evaluation)

Aluminum pigment

Grain size. ₂₎ D, @ Deckver¬

WBL morphology clouds

d50 '> [pm] ^p [pm] like [pm]

WBL25 Comfiake 19 fine 0.25 19.3 10 2-3

WBL26 Comfiake 34 coarse 0.25 17.6 12 3-4

WBL27 Comfiake 19 fine 0.09 16.3 14 3

WBL28 Cornflake 34 coarse 0.09 15.9 16 34

¹¹ Key figures according to the technical data sheet from Eckart

2 ¹ p / b = pigment-binder ratio Table 8.7: Results of the investigations with regard to the course depending on the layer thickness

Aluminum pigment 10-15 pm SD 15-20 pm SD 20-25 pm SD

Morpho grain size " _2j D"

ML SW DOf SW DOI SW DOI logle d50 ¹ > [pm] ^piD [pm]

WBL3 Comflake 16 fine 0.35 23.5 11.5 77.3 16.1 72.2 17.2 71.6

WBL5 Comflake 34 coarse 0.35 30.1 14.7 64.6 19.9 63.8 24.0 60.8

WBL4 Comflake 16 fine 0.13 26.8 8.6 85.1 11, 9 83.8 14.3 82.7

WBL6 Comflake 34 coarse 0.13 31.5 10.4 74.3 15.1 71.4 4 18.7 68.4

Table 6.8: Results of the investigations with regard to the course depending on the layer thickness

Aluminum pigment 15-20 pm SD 20-25 pm SD 25-30 pm SD Morpho grain size .. .. D10

WBL SW DOI SW DOI SW DOI

logle d »h M [pm]

WBL7 Comflake 16 fine 0.25 19.1 20.6 70.4 25.1 62.8 26.1 62.2

WBL9 Comflake 34 coarse 0.25 17.2 23.1 61.9 25.3 56.6 26.1 53.6

WBL8 Comflake 16 fine 0.09 15.9 14.1 81.4 20.4 76.1 23.8 72.2

WBL10 Comflake 34 coarse 0.09 15.6 19.6 68.8 21.7 67.1 24.5 63.1

Table 6.9: Results of the investigations regarding cloudiness

Aluminum pigment

WBL morphology M Mottling15 Motling45 Motling60

WBL3 Comflake 16 fine 0.35 23.5 3.8 4.2 4.1

WBL5 Comflake 34 coarse 0.35 30.1 3.4 5.3 4.9

WBL4 Comflake 16 fine 0.13 26.8 2.9 4.4 3.5

WBL6 Comflake 34 coarse 0.13 31, 5 4.8 4.4 6.3

Key figures according to the technical data sheet from Eckart

p / b = pigment-binder ratio In all cases examined (with different pigment contents in each case), an exchange of the effect pigment used, in particular with regard to its smaller grain size (based on the d50 value of the pigment) leads to smaller Di ₀ values. The resulting finer atomization has a positive effect on the opacity, the tendency to clouds as well as pinpricks and the course (SW and DOI).

8.5 Comparison between the water-based paints WBL17 to WBL24 with regard to pinholes (influence of the pigment content)

The investigations on the water-based paints WBL17 to WBL24 as well as WBL29 and WBL30 with regard to pinholes were carried out according to the method described above. In particular, it clarifies how the atomization and the resulting coating properties can be influenced based on the amount of aluminum pigments used. The outflow rate in all experiments was 300 ml / min; the speed of the ESTA-G locke was 43,000 rpm. Table 6.10 summarizes the results.

Table 6.10: Results of the investigations regarding needle sticks

Aluminum pigment

Grain size _{/ h2)} D «

WBL pinhole morphology

dSO ¹ * [pm] ^ [pm]

WBL17 Comflake 19 fine 0.35 24.8 90

WBL19 Comflake 19 fine 0.13 29.0 120

WBL18 Comflake 34 coarse 0.35 33.2 130

WBL20 Comflake 34 coarse 0.13 33.3 160

WBL21 silver dollar 12 fine 0.35 24.0 90

WBL22 Sllberdoilar 12 fine 0.13 28.6 140

WBL23 Silver Dollar 24 Coarse 0.35 29.3 80

WBL24 silver dollar 24 rough 0.13 32.4 100

Key figures according to the technical data sheet from Eckart

^2! p / b · »pigment-binder ratio In comparison of the respective sample pairs, which differ only with regard to the pigment

Binder ratio, ie with respect to the amount of pigment differ, it was found that increasing the amount of the aluminum pigment used in a better atomization led (smaller Di ₀ - erte) and thereby pinholes were affected positively.

6.6 Comparison between the waterborne basecoats WBL17 and WBL17a as well as WBL21 and WBL21a with regard to pinholes, degree of wetness and cloudiness (influence of spray viscosity or amount of water)

The investigations on the water-based paints WBL17 or WBL17a and WBL21 or WBL21a as well as WBL31 or WBL31a with regard to pinholes, degree of wetness and cloudiness were carried out according to the methods described above. In particular, it clarifies how the spraying viscosity (i.e. the amount of water added) can be used to influence the atomization and the resulting coating properties. The outflow rate in all experiments was 300 ml / min; the speed of the ESTA bell was 43,000 rpm. Tables 6.1 1 and 6.12 summarize the results. Table 6.1 1: Results of the investigations with regard to needlesticks, spray viscosity Dio

WCL pinpricks

[mPa-sp Ipm]

WBL17 80 24.8 90

WBL17a 120 29.0 120

WBL21 80 33.2 130

WBL21a 120 33.3 160

^1! set at a shear stress of 1000 s ¹ Table 6.12: Results of the investigations with regard to cloudiness and wetness

Spray viscosity D (10)

Wetness clouds

[mPa-sp [pm]

WBL31 130 36.2 4 4

WBL31a 80 24.0 2 2-3 set at a shear stress of 1000 s ¹

The examples show that a lower spray viscosity during the atomization of the material produces finer droplets (smaller Dio values), which have a positive effect on the sensitivity of the needlestick as well as on the wetness and cloudiness of the coating.

6.7 Comparison between the water-based paints WBL34 and WBL35 or

WBL34a and WBL35a in terms of wetness

The tests on the water-based paints WBL34 and WBL35 or WBL34a and WBL35a with regard to the degree of wetness were carried out according to the method described above. In particular, it clarifies how an additional amount of a solvent can be used to influence the atomization and the resulting degree of wetness, which is responsible for properties such as cloudy, needlestick robustness, etc. The tests on the samples were carried out at an ESTA bell speed of 43,000 rpm and 63,000 rpm. The outflow rate was 300 ml / min in all cases. Table 6.13 summarizes the results.

Table 6.13: Results of the studies regarding the degree of wetness

Speed spray viscosity Di ₀

WBL degree of wetness

[U / mln] [mPa-s] ¹ ) [mpp]

WBL34 63000 120 30.3 2

WBL35 63000 120 47.3 5

WBL34a 63000 80 31.3 2

WBL35a 63000 80 47.1 4

WBL34 43000 120 31, 4 2

WBL35 43000 120 49.7 5

WBL34a 43000 80 32.8 2

WBL35a 43000 80 38.2 4

For both outflow rates (63,000 U / min or 43,000 U / min) for the respective sample pairs, which were set to the same spray viscosity (120 mPa-s or 80 mPa-s), it could be shown that by adding butyl glycol the D ₁₀ value and This also influences the degree of wetness, which is the cause of, for example, sensitivity to clouds or needlestick; the solvent causes a significant increase in the D ₁₀ value as a measure of the particle size during the atomization and thus a much wetter deposited film.

6.8 The examples show that the method according to the invention can be used to make predictions for the atomization of a lacquer, which correlate with the qualitative properties of the final coating (number of pinholes, degree of niss, degree of cloudiness or course or appearance and opacity) and in particular better than other methods of Correlate state of the art. The method according to the invention thus enables a simple and efficient method for quality assurance. It can help to carry out paint development in a more targeted manner and at least partially dispense with complex coating processes for model substrates (including baking the materials).

7. Investigations on clear lacquers or the varnish obtained therefrom and

coatings

Comparison between the clear coats KL1, KL1a and KL1b regarding

runners limits

The tests on the clearcoats KL1 and KL1a and KL1b with regard to their run behavior were carried out according to the method described above. In particular, it clarifies how the runner behavior can be influenced on the basis of the spray viscosity adapted by the addition of a solvent and on the omission of additives known to the person skilled in the art, such as rheology control agents. The following materials are used:

Clear lacquer KL1

Sample KL1 is a commercially available two-component clear coat (ProGloss from BASF Coatings GmbH), containing pyrogenic silica as a rheological aid (Aerosil® types from Evonik), with the base coat included Ethyf-3-ethoxypropionate was set to a viscosity of 100 mPa-s at 1000 / s.

Clear lacquer KL1a

Sample KL1a corresponds to KL1 with the difference that the base paint was adjusted to a viscosity of 50 mPa-s at 1000 / s with ethyl 3-ethoxypropionate.

Clear coat KL1 b

Sample KL1b corresponds to KL1 with the difference that it contains no pyrogenic silica as a rheological aid. The base coat was also adjusted to a viscosity of 100 mPa-s at 1000 / s with Ethy! -3-ethoxypropionate as in the case of KL.

The tests were carried out on the samples at an ESTA bell speed of 55,000 rpm. The outflow rate was 550 ml / min. Table 7.1 summarizes the results.

Table 7.1: Results of the investigations regarding the runner behavior

D «Runner start (> 0 mm) runner limit {> 10 mm)

clearcoat

Ipm] [pm] [pm]

KL1 41.28 48 58

KL1a 41.95 38 44

KL1b 42.96 36 42

The results show that receptive measures influencing the viscosity behavior, such as reducing the spray viscosity (KL1a) or eliminating the rheology aids based on pyrogenic silica (KL1 b), deteriorate the atomization compared to the reference KL1 (larger D-io values), which results in a deterioration in rotor stability.

The examples demonstrate that the method according to the invention can also be used to make predictions for the atomization of a lacquer, particularly for clear lacquers, which correlate with qualitative properties of the final coating (runner behavior) and in particular better than other methods of Correlate state of the art. The method according to the invention thus enables a simple and efficient method for quality assurance. It can help _»to carry out paint development in a more targeted manner and at least to partially despise the complex coating processes for model substrates (including the burning in of the materials).

Claims

Expectations;

1. A method for determining the droplet size distribution within a spray and / or the homogeneity of this spray, the spray being formed when atomizing a coating composition which comprises at least steps (1) to (3), namely

(1) atomizing the coating composition by means of an atomizer, a spray being formed by the atomization,

(2) optical detection of the drops of the spray formed by atomization according to step (1) by a traversing optical measurement through the entire spray, the optical detection according to step (2) traversing in the radial-axial direction with respect to the tilted atomizer used a tilt angle of 0 ° to 90 °, and

(3) Determination of at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray based on optical data obtained by the optical detection according to step (2), the homogeneity of the spray being the ratio of two quotients Tti / Ty _ot aii and Tt ₂ / T _Toΐ 3 _ΐ 2 to each other as a measure of the local distribution of transparent and non-transparent drops at two different positions within the spray, where T _{Ti is} the number of transparent drops in the first position 1, Ti2 the number of transparent drops in the second position 2, Tjotan the number of all drops in the spray and thus the sum of transparent drops and non-transparent drops in position 1 and Tj _otass the number of all drops in the spray and thus the sum of transparent drops and non-transparent Drop in position 2 corresponds, whereby position 1 is closer to the center of the spray than position 2.

2. The method according to claim 1, characterized in that the coating composition used in step (1) is a preferably aqueous basecoat.

3. The method according to claim 1 or 2, characterized in that the coating composition used in step (1) at least one polymer replaceable as a binder as component (a), at least one pigment and / or at least one filler as component (b) and water and / or contains at least one organic solvent as component (c)

4. The method according to claim 3, characterized in that as component (b) at least one effect pigment is contained in the coating composition.

5. The method according to any one of the preceding claims, characterized in that the atomization according to step (1) is carried out at an outflow rate of the coating composition to be atomized in a range from 100 to 1,000 ml / min.

6. The method according to any one of the preceding claims, characterized in that the determination of the at least one parameter of the drop size distribution in step (3) includes the determination of the D ₁₀ value of the drops as a parameter.

7. The method according to any one of the preceding claims, characterized in that the optical detection according to step (2) by means of phase Doppler anemometry (PDA) and / or by means of time-shift measurement technology (TS).

8. The method according to any one of the preceding claims, characterized in that the determination of the at least one »characteristic of the drop size distribution according to step (3) on the basis of the optical Optical data obtained according to step (2) is acquired, which means

Phase Doppler anemometry (PDA) and / or by means of the time shift

Measurement technology (TS) have been obtained.

9. The method according to any one of the preceding claims, characterized in that the homogeneity is determined according to step (3) on the basis of optical data obtained by the optical detection according to step (2) using time-shift measurement technology (TS) have been obtained.

10. The method according to any one of the preceding claims, characterized in that the optical detection according to step (2) traversing in the radial-axial direction with respect to the tilted atomizer used at a tilt angle of> 0 ° to <90 °.

11. A method for creating and / or updating an electronic database comprising at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray of atomized and different coating composition, the method comprising at least steps (1) to (3), (4A) and (5A), namely

Steps (1), (2) and (3) as defined in one of claims 1 to 10 for a first coating composition (i),

(4A) incorporation of the at least one parameter of the droplet size distribution within the spray and / or the determined homogeneity of the spray into an electronic database, determined for step (3) for the first coating composition (i), and

12. The method according to claim 1 1, characterized in that it additionally comprises at least the further steps (3A), (3B) and (3C), namely

(3A) applying the first coating composition (i) atomized in document (1) to a substrate to form a film on the substrate and baking this film to form a coating on the substrate,

(3B) Examination and assessment of the coating obtained according to step (3A) with regard to the occurrence or non-occurrence of

Surface defects and / or optical defects and

(3C) incorporating the results obtained after performing step (3B) into the electronic database, wherein step (5A) repeats these steps (3A), (3B) and (3C) at least once for the at least one further of the first coating composition (i) includes various coating composition.

13. A method for screening coating compositions in the development of coating formulations, which comprises at least steps (1) to (3), (4B), (5B) and (6B) and optionally (7B), namely

Steps (1), (2) and (3) as defined in one of claims 1 to 10 for a coating composition (X1),

(4B) Comparison of the at least one parameter of the droplet size distribution within the spray and / or the homogeneity of the spray determined according to step (3) for the coating composition (X1) with parameters of the droplet size distribution within the spray and / or of the stored in an electronic database Homogeneity of the spray of further coating compositions, this database being obtainable by means of the method according to claim 11 or 12, (5B) Checking on the basis of the comparison according to step (4B) whether the at least one parameter of the drop size distribution within the spray and / or the homogeneity of the spray determined according to step (3) for the coating composition (X1) fulfills the condition that it is less As at least one parameter stored in the database of the drop size distribution within the spray and / or the homogeneity of the spray, a coating composition (X2), which differs from the coating composition (X1), but is a pigment identical to the coating composition (X1) Contains content or has such a pigment content that deviates by a maximum of ± 10 wt .-% from the pigment content of the coating composition (X1), based on the amount of pigment present in the coating composition (X1), and which also the or the identical pigment (s) or that or the essentially contains an identical pigment (s) as the coating composition (X1),

(6B) Selection of coating composition (X1) for application to a substrate, if that for the

Coating agent composition (X1) determined at least one parameter of the drop size distribution within the spray and / or the determined homogeneity of the spray fulfills the condition specified in step (5B) or

Adjust at least one parameter within the recipe

Coating agent composition (X1) and / or at least one process parameter when carrying out steps (1) to (3) of the process for screening coating agent compositions, if the at least one parameter of the drop size distribution within the spray determined for the coating agent composition (X1) and / or the certain homogeneity of the spray does not meet the condition specified in step (5B), (7B) at least one simple repetition of steps (1) to (3), (4B) and (5B), if at least one parameter adjustment was necessary in accordance with step (6B), until after at least one simple repetition of step (6B) due to to fulfill the condition in step (5B) according to step (6B), a selection of the coating composition used is made for application to a substrate.

14. The method according to claim 13, characterized in that the adaptation of at least one parameter within the recipe of the coating composition (X1) and / or at least one process parameter when carrying out steps (1) to (3) according to step (6B) at least one Adjustment selected from the group of adjustments of the following parameters includes:

(i) increasing or decreasing the amount of at least one polymer contained in the coating composition (X1) as binder component (a),

(ii) at least partial exchange of at least one in

Coating composition (X1) as

Binder component (a) containing polymers by at least one polymer different from this,

(iii) increasing or decreasing the amount of at least one in the

(iv) at least partial exchange of at least one in the

Coating agent composition (X1) as filler (b) contained by at least one different filler,

(v) increasing or decreasing the amount of at least one in the

Coating agent composition (X1) as component (c) contained organic solvent and / or water contained therein,

(vi) at least partial exchange of at least one in the

Coating agent composition (XI) as component (c) organic solvent contained by at least one organic solvent different from this,

(vii) increasing or decreasing the amount of at least one in the

Coating composition (X1) as component (d) containing additive,

(viii) at least partial exchange of at least one in the

Coating composition (X1) as component (d) containing additive by at least one additive different from this,

(ix) changing the order of those used to prepare the coating composition (X1)

Components and / or

(x) increase or decrease the energy input of the

Mixing in the manufacture of the

Coating agent composition (X1). , The method according to claim 13 or 14, characterized in that the method is a method for screening aqueous basecoats which contain at least one effect pigment as a component (b).