MX2007005504A - A method of matching a color in a powder paint system including metallic pigment with a color of a liquid paint system - Google Patents

Abstract

A method of matching a color of a powder paint system including a metallic pigment with a color of a liquid paint system includes applying the liquid paint system onto a substrate. A color effect-providing pigment different than the metallic pigment is added to the liquid paint system to match the color of the powder paint system with the color of the liquid paint system. The color of the liquid paint system including the color effect-providing pigment substantially matches the color of the powder paint system that includes the metallic pigment.

Description

A METHOD OF EQUALIZING A COLOR IN A PAINTING SYSTEM IN POWDER INCLUDING METALLIC PIGMENT WITH A COLOR OF A LIQUID PAINT SYSTEM BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention generally refers to a method of matching a color of two painted regions with two different paint systems. More specifically, the present invention relates to a method of equalizing a color of a powder paint system with a color of a liquid paint system. 2. DESCRIPTION OF THE RELATED TECHNIQUE Modern vehicles, such as automobiles, are typically offered to consumers in a wide variety of paint colors. In fact, from model to model, it is not uncommon for a particular vehicle model to be available in several new paint colors. Different types of paint systems can be used to paint the vehicles. One type of paint system used to paint vehicles is a powder coating system. Powder coating systems are used for certain functional and aesthetic purposes. The patents of E.U.A. Us. ,379,947; 5,552,487; 5,569,539; 5,601,878; and 5,639,821 all describe various powder coating systems known in the prior art. Powder coating systems have been in favor since they provide environmental advantages, such as reduced VOCs on conventional liquid paint systems. As a result, some large vehicle manufacturers favor the use of powder coating systems. In powder coating systems, a powder paint composition is electrically charged and deposited on a charged substrate to form a film layer. The film layer is then baked to cure the powder paint composition. It is also known in the art to incorporate conventional pigments, and even conventionally effect pigments, specifically metal pigments, into powder-based coating compositions. As is often the case, portions of vehicles need to be repainted, often as a result of a defect such as lint, paint scratches, stains, etc. These defects can be introduced during the manufacture and assembly of the vehicle. The vehicles also need to be repainted after a crash in the finishing industry. In addition, many parts suppliers that provide components such as fenders, mirror housings, molds, and the like must paint the components before delivering the components to vehicle manufacturers. The facilities and tools required to use the powder coating systems are relatively expensive, compared to the facilities and tools required for liquid paint systems. As a result, liquid paint systems provide the best available option in many situations. One of the problems that arises for the suppliers of spare parts and those portions of repainting the vehicle with liquid paint systems is that it is essential to match a vehicle color resulting from the powder paint system with a color resulting from the liquid paint composition. . Various systems and methods are known in the art that help determine a paint formula for the portion to be painted or repainted. However, these systems and methods are not suitable for matching a color of a powder paint system that includes metallic pigment with a color of the liquid paint system. More specifically, liquid and powder paint systems cure differently, and the color of the powder coating system is notoriously different from the color of the liquid paint system when metal pigment is included in the powder coating system. This is even if the same pigments, in the same amounts, are included in the liquid paint system and the powder coating system. As a result, up to this point, it has been unsatisfactory to match the color of powder coating systems that include metallic pigment with the color of liquid paint systems.

As such, there remains an opportunity to provide a method of matching the colors of two painted vehicle surfaces with two different paint systems, namely, a method of matching the color of the powder paint system including metallic pigment with the color of the system. of liquid paint.

BRIEF DESCRIPTION OF THE INVENTION The present invention provides a method of equalizing a color of a powder paint system including a metallic pigment with a color of a liquid paint system. The method includes the steps of adding a color effect pigment supplier different from the metallic pigment to the liquid paint system to match the color of the powder paint system with the color of the liquid paint system, and apply the liquid paint system in a substrate to obtain the second color. The second color of the liquid paint system including the color effect provider pigment substantially matches the first color of the powder paint system which is different from the metallic pigment in the powder coating system to effectively match the two paint systems.

DETAILED DESCRIPTION OF THE PREFERRED MODALITY A method of matching a color of two regions pini &das with two different paint systems is used primarily in the automotive industry. More specifically, the method is to equalize a color of a first region by having a powder paint system including a metallic pigment with a color of a second region having a liquid paint system. Although the first region is typically included in a substrate that is formed of metal, such as a vehicle body, the first region may be included in other substrates without varying the scope of the present invention. By way of example, the first region can be included in a plastic substrate. The method of matching the paint colors of the two regions with the different painting systems is useful when the vehicle body including the powder coating system is damaged and needs to be repainted, which can be as a result of a shock , paint rayon, etc. For example, the method of the present invention can be useful for vehicle manufacturers when the vehicle body including the powder coating system is damaged during production. In this situation, the first region and the second region are on the same substrate, and the liquid paint system can be applied to the damaged region of the powder coating system, i.e., the second region. As used herein, "same substrate" refers to the same part, such as a chest, fender, or vehicle door. It should be appreciated that the second region may be within the first region, for example, as a rayon, ie, the second region, in the hood including the powder coating system. Many parts suppliers that provide components such as fenders, mirror housings, molds, and the like, must paint the components before delivering the components to vehicle manufacturers. In this situation, the first region including the powder paint composition can be in a sample plate or in the vehicle body. The sample plate can be compared to the component for the vehicle, ie, the second region, including the liquid paint system. In this way, the first region including the powder coating system can be in the sample or in the vehicle body, and the second region is in a different substrate, i.e., the component, such as the defense, mirror housing or mold. To match the two colors, the powder paint system including the metallic pigment can be applied to the first region. However, it should be appreciated that the powder coating system may have been previously applied in the first region by another entity, such as a paint manufacturer or the vehicle manufacturer. Methods of applying powder coating systems are known in the art. More specifically, in powder coating systems, a powder paint composition is loaded electrically and is deposited on a charged substrate, ie, the vehicle body, to form a layer of powder paint. The powder paint composition can be applied to the first region with or without an underlying base layer. After the powder coating layer is formed, the powder coating layer is then baked to cure the powder coating layer. The powder paint composition typically includes a powder-based binder and the metallic pigment. Metal pigments are known in the art and are widely used in powder coating systems. Metallic pigments, as referred to herein, include pellets or flakes of aluminum, gold, bronze, zinc, stainless steel, copper and copper alloys including brass and bronze, and combinations thereof. Scales are commercially available in a range of particle sizes, and the particular particle size varies based on the application. Examples of suitable metallic pigments are commercially available under the trademark Sparkle Silver® from Silberline anufacturing Co. of Tamaqua, PA. Preferably, the metallic pigment is aluminum flake. Such metal pigments are known in the art and are commercially available from a number of manufacturers. The metallic pigment in the powder coating layer, after curing, reflects light to provide a shine or scintillation effect. The powder-based binder is a film-forming binder that includes a resin and an entanglement agent. The resin includes a functional group, and the crosslinking agent is specifically reactive with the functional group of the resin. More specifically, the poivo-based binder resin can be selected from the group of acrylic resins, epoxy resins, phenolic resins, polyester resins, urethane resins, and combinations thereof. The functional group of the resin can be selected from the group of epoxy functional groups, epoxy functional groups, hydroxy functional groups, and combinations thereof. The entanglement agent can be selected from the group of aminoplasts, blocked isocyanates, polycarboxylic acids, acid anhydrides, polyamines, and combinations thereof. According to the present invention, an equalization of the color of the powder paint system with the color of the liquid paint system can be achieved by adding a pigment providing a different color effect of the metallic pigment to the liquid paint system, as described in detail later. More specifically, the liquid paint system including the color effect provider pigment is applied to the second region to obtain the second color, and as a result of the presence of the color effect provider pigment in the liquid paint system, the second color substantially equalizes the powder paint system including the metallic pigment after curing.

The color effect provider pigment has a pigment substrate and an inorganic coating disposed on the pigment substrate. The pigment substrate has first and second substantially parallel and flat surfaces, and the inorganic coating is disposed or applied to at least one of the first and second substantially parallel and flat surfaces of the pigment substrate. Preferably, the inorganic coating is disposed or applied to both the first and second substantially parallel and flat surfaces. The pigment substrate is preferably a pigment substrate in the form of a platelet. As used herein, the platelet-shaped terminology indicates that the pigment substrate is a minute, flattened body. In addition, the pigment substrate is preferably selected from the group of metallic pigment substrates, non-metallic pigment substrates, and combinations thereof, depending on the particular color to be matched in the powder coating system. In an embodiment where the pigment substrate is a metallic pigment substrate, the most preferred metallic pigment substrate is aluminum. Other suitable metal pigment substrates include, but are not limited to, all metals and platelet-shaped alloys known as metallic pigment substrates, such as gold, bronze, zinc, stainless steel, copper, and copper alloys including brass and bronze. The aluminum pigment substrate can be a passivated or non-passivated aluminum pigment substrate.

In an embodiment wherein the pigment substrate is a non-metallic pigment substrate, the most preferred non-metallic pigment substrate is mica. Other suitable non-metallic pigment substrates include, but are not limited to, borosilicates. The inorganic coating of the color effect provider pigment also varies depending on the particular color to be matched in the powder coating system. The inorganic coating can be selected from the group of metal oxides, magnesium fluoride, silicon oxide, silicon oxide hydrate, aluminum oxide, aluminum oxide hydrate, titanium oxide, titanium oxide hydrate, sulfide zinc, magnesium fluoride, and combinations thereof. The color effect providing pigments suitable for the present invention are known in the art and are commercially available from a number of manufacturers. An example of a color effect providing pigment as such having the metallic pigment substrate is Paliocrom® Gold L 2000, commercially available from BASF Corporation of Southfield, MI. Examples of the color effect provider pigment having the non-metallic pigment substrate include pigments are commercially available under the trademark Lumina® from Engelhard Corporation of Iselin, NJ. The color effect provider pigment is selected based on the color of the powder coating system. The color effect provider pigments available in a limited variety of colors, and pigments color effect providers suitable for purposes of matching the color of the powder coating system only need to be in the same color family as the color of the powder coating system. For example, if the color of the powder coating system is orange, then an orange or gold effect pigment supplier can be used. The liquid paint system may include a base coat, a middle coat and a clear coat. As such, the step of applying the liquid paint system may include applying a liquid basecoating composition in the second region to form the basecoat, applying a liquid middlecoat composition to the basecoat to form the middlecoat, and applying a transparent layer composition in the middle layer to form the transparent layer. The clear layer composition may be a liquid or powder-based clear coat composition. The liquid basecoat, liquid medium layer and clearcoat compositions can be applied through any conventional application method, such as by spraying, and preferably applied wet on wet. Once the layers are formed to complete the liquid paint system, the liquid paint system is then typically cured. Liquid base coat compositions are known in the art, and the liquid base coat composition can be any known liquid base coat composition having a specified clarity value and which is capable of hiding the substrate in a type of film of no more than 50 micras. The clarity values of the liquid basecoat composition are described in greater detail below. It should be appreciated that all powder coating systems are different, and the liquid base coat composition having the specified clarity values can be unique to the powder coating system to be matched. The liquid basecoating composition can be water or solvent, and includes a pigment, a resin, an entanglement agent, a catalyst, and other additives, all of which are known in the art. Some of the commonly used color pigments that can be included in the liquid basecoat composition are green and blue based on copper phthalocyanine, quinacridone red, iron oxide red, iron oxide yellow, dirarilide yellow, Perinone orange, indanthrene blue, Chromophthalo red, Irgazina orange, and Heliogen green. Preferably, the liquid basecoating composition is essentially free of barites, titanium dioxide, and any other pigment that is known to decrease transparency or increase the opacity of the liquid paint system. As stated above, the pigment color effect provider is added to the liquid paint system. More specifically, the color effect provider pigment is added to the liquid medium layer composition in order to equalize the color of the powder paint system with the color of the liquid paint system, i.e., the color effect supplier pigment in the middle layer, it mimics the effect of the metallic pigment in the powder coating system. He Pigment color effect provider is typically added to the liquid paint system via a pigment dispersion. The liquid medium layer composition may be water or solvent. In addition to the pigment color effect, or pigment dispersion provider, the liquid middle layer composition further includes a middle layer resin, a middle layer entangling agent, a catalyst and, optionally, other additives, all of which are known in the art to be included in liquid medium layer compositions. The middle layer resin, medium layer entanglement agent, catalyst, and other additives may be the same or different from the resin, crosslinking agent, catalyst and other additives in the liquid basecoating composition. Preferably, the liquid middle layer composition is formulated to maximize the transparency and minimize opacity of the formed middle layer of the liquid middle layer composition. As already mentioned above, the liquid middle layer composition is preferably free of barites, titanium dioxide, or any other pigment that is known to decrease transparency or increase opacity. In addition, the liquid medium layer composition preferably has a pigment to binder ratio of about 0.05 to about 0.06. As a result, the formed middle layer of the liquid medium layer composition mimics the effect of the metallic pigment in the powder paint composition without substantially hiding the color of the base layer.

As is known in the art, the color of the powder coating system including the metallic effect pigment can not easily be measured by objective testing with current "multiple angle" otometer spectrometers. More specifically, the actual color values of the powder coating system at viewing angles of 15 °, 25 °, 45 °, 75 ° and 110 ° in Lab color space, as measured by multiple angle spectrophotometers, often They are inconsistent for the same powder paint system due to the presence of metallic pigment. As such, the visual comparison is typically used to match the color of the powder coating system with the color of the liquid paint system. To achieve visual equalization, you may need to create many formulations of the liquid paint system. In an alternative mode, it should be appreciated that multi-angle spectrophotometers, although not ideal, can be used to measure the color of the powder coating system. An example of a multi-angle otometer spectrometer is the MA68II Portable Multi-Angle Spectrophotometer commercially available from X-rite of Grandville, MI. In this way, the actual color values of the powder coating system can be determined with said otometer spectrometer at 15 °, 25 ° and 110 ° angles of view, and therefore the liquid basecoat composition can be formulated.

As stated above, the method of the present invention may include the step of visually comparing the powder paint system with the liquid paint system. There is some consensus Within the industry, the human eye can only detect differences in color that are greater than about 6 units of color from each other in any of the Lab color settings. More specifically, while multiple-angle spectrophotometers can detect differences in color On the magnitude of 1 unit of color, the human eye can only detect a difference over the magnitude of at least 6 units of color. As such, for purposes of the present invention, "equalize" or "substantially equalize" refers to a difference between the colors of no more than about 6 color units for the color value given in the Lab color space, with 1 unit of color being the differences in color that can be measured with multiple angle spectrophotometers. If no color value is specified, then "match" or "substantially match" refers to a difference between the colors of no more than about 6 color units for each of the Lab color values. Preferably, a difference between the colors is not greater than 4 units of color in each of the Lab color values. Preferably, the liquid basecoating composition substantially equals the color of the powder coating system. More specifically, the liquid basecoat composition preferably has a documented lightness value slightly lower at the 110 ° angle of view than a clarity value of the powder coating system at the 110 ° angle of view. As used in the present, "documented clarity value" or any "documented" color value, refers to a color value that is predetermined either through the use of the eye ofotometer in another base layer formed of the same liquid basecoat composition, or a color value that is obtained from a manufacturer of the liquid basecoat composition. As described above, the actual color values of the powder coating system are often inconsistent, so it can be difficult to determine an appropriate clarity value of the color of the liquid paint system. As such, during the initial formulation of the basecoat composition, the multiple basecoat compositions may have to be formulated and it may be necessary to make visual comparison of basecoats of the basecoat composition until said match is obtained. The liquid basecoat composition preferably has a documented clarity value at the 110 ° view angle which is not more than 10% less than the clarity value at the 110 ° view angle of the powder coating system, which it contributes to the equalization between the color of the powder coating system and the color of the liquid paint system. In addition, the liquid basecoating composition preferably hides the black in a film type of no more than 50 microns in order to minimize the amount of liquid basecoating composition to hide the substrate or any layer below the basecoat. During the application of the liquid medium layer composition in the base layer to form the middle layer, the layer composition Liquid medium is preferably applied until a color of the middle layer substantially equals a clarity value of the powder coating system at 15 ° and 25 ° viewing angles. More specifically, the liquid medium layer composition can be applied at the same time by visually comparing the sample including the powder paint system with the liquid paint system, and continuing with the application of the liquid medium layer composition until visual equalization is achieved between the color of the powder coating system and the color of the liquid paint system. Alternatively, an automated system can be used to apply the liquid medium layer composition based on a predetermined series of application parameters. As described above, the human eye can only detect differences in color that are greater than about 6 color units with each other at any of the Lab color values. Accordingly, the liquid medium layer composition is preferably applied until the Second color of the liquid paint system has a clarity differential of no more than about 6 color units of the clarity value of the powder coating system at 15 ° and 25 ° viewing angles. Although the Lab color values can not be determined when the liquid middle layer is still wet, a series of samples may have to be made including the middle layer, and the Lab color values determined from the samples after curing the middle layer for determine appropriate application parameters to obtain the differential of clarity of no more than about 6 color units of the clarity value of the powder coating system at 15 ° and 25 ° viewing angles. The exact application parameters will vary depending on the colors to be matched, and it should be appreciated that many liquid medium layer compositions may have to be formulated to obtain said equalization. After forming the middle layer, the clearcoat composition can then be applied in the middle layer to form the transparent layer. Said transparent layer compositions, as well as methods of applying the clearcoat compositions, are known in the art. The following example, as presented herein, should illustrate and not limit the invention.

EXAMPLE Powder painting system A sample is obtained having an orange metallic powder paint system disposed therein. The sample is used for visual comparison to formulate a liquid clear coat composition and a liquid mid layer composition that substantially matches the color of the powder paint system.

Liquid paint system For preparing the liquid paint system, a binder composition is first prepared that is used in a liquid basecoat composition and a liquid midcoat composition. The components included in the binder composition are set forth in Table 1 below, together with relative amounts. All amounts are in parts by weight based on the total weight of the binder composition unless otherwise indicated.

TABLE 1 Resin A is a microgel at approximately 31% NV. Resin B is a flexible hydroxy functional acrylic resin at approximately 73% NV. Interlacing agent is Resimene 755 melamine. UVA is an ultraviolet light absorber based on hydroxyl phenyl benzotriazole, sold under the tradename Tinuvin 1130, commercially available from Ciba Specialty Chemicals of Tarrytown, NJ. Catalyst B is Nacure 5225 commercially available from King Industries of Norwalk, CT. Solvent A is n-methyl pyrrolidone. Solvent B is denatured ethanol. Solvent C is butyl acetate. Solvent D is Exoxate® 600 oxo-alkyl acetic ester commercially available from Exxon Mobil Corporation of Houston, TX Additive A is amino methyl propanol. Additive B is an acrylic additive.

Additive C is barium sulfate dispersed in high solids acrylic resin. Additive D is a smoked silica dispersed in high-strength acrylic rebinte. Then, the binder composition is used to make the middle layer and liquid base layer compositions. To make the liquid medium layer composition, a color effect provider pigment is selected based on the observation of the powder coating system, and the color effect provider pigment is mixed in the binder composition. liquid medium layer compositions are made including the color effect providing pigment, and medium layers are formed with the liquid middle layer compositions and cured to a middle layer having a clarity value that substantially equals a clarity value of powder coating system at 15 ° and 25 ° viewing angles. In this example, since the orange metallic powder paint system must be matched, Paliocrom® Gold L 2000 is a pigment providing the color effect suitable for the liquid medium layer composition. To obtain the substantial equalization in clarity values between the middle layer and the powder paint system, then 10 grams of the Paliocrom® Gold L 2000 is mixed with 600 grams of the binder composition. To make the liquid basecoat composition, once again, liquid basecoat compositions are made, and basecoats of the liquid basecoat compositions are formed and cured. until obtaining a base coat having a clarity value that is slightly darker than a clarity value of the powder paint system at the 110 ° angle of view. To obtain the desired clarity value of the base layer, 600 grams of the binder composition are mixed together with 263 grams of red black oxide dispersion in high solids acrylic resin, 127 grams of Paliocrom® Gold L 2000, 105 grams of dispersion of opaque yellow iron oxide in high solids acrylic resin, and 875 grams of bismuth vanadate dispersion in high solids acrylic resin. To apply the liquid paint system, the liquid basecoat composition is first sprayed onto a metal substrate in an amount sufficient to hide the substrate and to form a basecoat. While the base layer is still wet, the liquid middle layer composition is sprayed on the base coat until a color of the middle layer in the base coat visually matches the color of the powder paint system. The binder composition alone, i.e., free of any additive or pigment, is used as a clearcoat composition and sprayed on the middle layer to form a clearcoat. Then the liquid paint system is cured including the base coat, the middle coat, and the clear coat. The liquid paint system prepared as described above visually equals the powder coating system. The invention has been described in an illustrative er, and it should be understood that the terminology that has been used should be in the nature of description words instead of limitation. Obviously, many modifications and variations of the present invention are possible in view of the above teachings, and the invention can be practiced otherwise unless specifically described.

Claims (2)

1 - . 1 - A method of equalizing a color of two regions painted with two different paint systems, said method comprising the steps of: applying a powder paint system including a metallic pigment to a first region to obtain a first color. 2. - A method according to claim 1, wherein the color effect provider pigment has a pigment substrate and an inorganic coating disposed on the pigment substrate. 3. - A method according to claim 1, wherein the step of applying the liquid paint system further comprises applying a liquid base coat composition in the second region to form a base layer. 4 - A method according to claim 3, wherein the step of applying the liquid paint system further comprises applying a liquid middle layer composition to the base layer to form a middle layer. 5 - A method according to claim 4, wherein the step of applying the liquid paint system further comprises applying a clear layer composition on the middle layer to form a transparent layer. 6. A method according to claim 4, wherein the step of adding the color effect provider pigment to the Liquid paint system comprises adding the color effect provider pigment to the liquid medium layer composition. 7 - A method according to claim 6, wherein the liquid medium layer composition further comprises a middle layer resin, a middle layer entanglement agent and a catalyst. 8 - A method according to claim 7, wherein the liquid medium layer composition has a pigment to binder ratio of about 0.05 to about 0.06. 9. A method according to claim 7, wherein the liquid medium layer composition is substantially free of barites and titanium dioxide. 10. A method according to claim 4, wherein said step of applying the liquid medium layer composition is defined more as applying the liquid medium layer composition until a color of the middle layer substantially equals a value of clarity of the powder coating system at 15 ° and 25 ° viewing angles. 11 - A method according to claim 10, wherein the middle layer has a clarity differential of no more than about 6 color units in Lab color space of the clarity value of the powder coating system at the viewing angles of 15th and 25th. 12. A method according to claim 11, wherein the liquid basecoat composition has a clarity value documented less than the 110 ° angle of view than a clear value of the powder paint system at the 110 ° angle of view. 13 - A method according to claim 12, wherein the liquid base coat composition has a documented clarity value at the 110 ° angle of view that is not more than 10% less than the clarity value at the angle of view of 110 ° of the powder paint system. 14. - A method according to claim 10, wherein the liquid basecoat composition hides black in a film type of not more than 50 microns. 15. - A method according to the rei indication 14, wherein the liquid basecoat composition is substantially free of barites and titanium dioxide. 16. - A method according to claim 10, further comprising the step of determining actual color values of the powder coating system with a spectrophotometer at the viewing angles of 15 °, 25 ° and 110 °. 17 - A method according to claim 1, wherein the first region and the second region are included in the same substrate. 18 - A method according to claim 1, wherein the first region and the second region are included in different substrates. 19. - A method of matching a color of a powder paint system including a metallic pigment with a color of a liquid paint system, said method comprising pas = of: applying a liquid basecoating composition on a substrate to form a basecoat, applying a liquid middlecoat composition on the basecoat to form a middlecoat, adding a pigment effect provider Different color of the metallic pigment to the liquid medium layer composition to match the color of the powder coating system; and applying a clear coat composition on the middle layer to form a clear coat. 20. - A method according to claim 19, wherein the color effect provider pigment has a pigment substrate and an inorganic coating disposed on the pigment substrate. 21 - A method according to claim 19, wherein the liquid medium layer composition further comprises a binder. 2

2 - A method according to claim 21, wherein the liquid medium layer composition has a pigment to binder ratio of about 0.05 to about 0.06. 23. - A method according to claim 21, wherein the liquid medium layer composition is substantially free of barites and titanium dioxide. 24 - A method according to claim 19, wherein said step of applying the liquid medium layer composition is defined more as applying the liquid medium layer composition until a color of the middle layer substantially equals a clarity value of the system of powder paint at angles of 15 ° and 25 °. 25 - A method according to claim 24, wherein the middle layer has a clarity differential of no more than about 6 color units of a clarity value of the powder paint system at the 15 ° view angles and 25 °. 26 - A method according to claim 25, wherein the liquid base coat composition has a documented clarity value less than the 110 ° angle of view than a clarity value at the 110 ° view angle of the paint system in dust. 27 - A method according to claim 26, wherein the liquid basecoat composition has a documented clarity value at the 110 ° angle of view which is no more than 10% less than the clarity value at the angle of view of 110 ° of the powder paint system. 28 - A method according to claim 19, further comprising the step of determining actual color values of the powder coating system with a spectrophotometer at the 15th, 25th and 110th angles of view. 29 - A method according to claim 19, wherein the liquid base coat composition hides the black in a film type of not more than 50 microns. 30 - A method according to claim 29, wherein the liquid basecoating composition is substantially free of barites and titanium dioxide.