JP2020042000A - Method for measuring color of coated plate and method for matching color using the same - Google Patents

Abstract

To provide a method for measuring the color of a coated plate having a multilayer coating film including a colored coating film by color paint and a clear coating film by clear paint, capable of simply and accurately measuring the color of the same multilayer coating film as the actual repair process in a shorter time without staining a colorimeter.SOLUTION: The method for measuring the color of a coated plate comprises: (1) coating color paint to form a colored coating film; (2) coating clear paint on the colored coating film to form a clear coating film; and (3-1) measuring the color of a protective sheet having at least an opened color measuring region of a coated plate using a colorimeter from the surface of the clear coating film within 5 minutes after forming the clear coating film in a state interposed between the surface of the clear coating film and the colorimeter or (3-2) measuring the color of the protective sheet having at least the opened color measuring region of the coated plate using the colorimeter from the surface of the clear coating film in a state interposed between the surface of the clear coating film in a state not completely dried and the colorimeter.SELECTED DRAWING: Figure 3

Description

[Cross Reference of Related Applications] The present application is filed in Japanese Patent Application No. 2018-168261 filed on September 7, 2018 (the entire disclosure of which is incorporated herein by reference). Claim priority based on:
The present invention relates to a colorimetry method for a coated plate having a multilayer coating film including a colored coating film made of a colored paint and a clear coating film made of a clear coating material, and a toning method using the method.

  In a paint shop, a car repair shop, a color-matching factory, and the like, there is a work process of preparing a painted plate and measuring the color using a colorimeter.

  In the field of automotive repair painting, it has become common to employ a computer toning method (computer color matching; CCM) using a color sensor and a computer for the purpose of standardizing the toning work and shortening the working time. . The computer toning method does not require advanced toning skills, so anyone can easily perform toning quickly and contributes to overall productivity improvement and is widely used. It is.

  In the computer toning method (computer color matching; CCM), data such as characteristic values of each toning material is input to a computer in advance, and the car body to be repaired is measured with a color sensor to obtain various data. Based on the data, the mixing ratio of the toning material was calculated by a computer, and based on the obtained mixing ratio, one or more toning materials were weighed and mixed to prepare a colored coating material. A colored paint is applied to a substrate and dried to produce a toning test coated plate.

  The prepared toning test coated plate is used for colorimetry and / or colorimetry with the periphery of the repaired part by a colorimeter. If the result is not good, recalculate with a computer based on the colorimetric data etc. of the prepared toning test coating plate and correct the formulation of the toning material, or modify the formulation according to the operator's feeling and adjust the toning Then, it is necessary to repeat the operation of producing a toning test coated plate again, and measuring the color of the toned test coated plate with a colorimeter and / or colorimetrically comparing with the periphery of the repaired portion until the test passes.

  At the actual repair painting site, for example, at the time of repair painting of an automobile outer panel, etc., a damaged paint is filled with putty or surfacer, and then mixed with at least one kind of toning material to be adjusted to a target color. Is applied around the damaged area, and a clear paint is applied thereon. The target color is the color around the repaired part, which may have changed from the color tone at the time of the new vehicle due to the effects of sunlight or the like. In order to finish the appearance without any color, it is necessary to prepare a large number of toning test coated plates having a multi-layer coating film, measure these colors, and perform colorimetry.

Therefore, in order to match the color of the part to be painted with the surroundings and finish it with an uncomfortable appearance, one or more kinds of toning materials are mixed using a computer toning method, and a colored paint toned toward the target color is used. To form a colored coating film, apply a clear coating on it, form a clear coating film, provide a multi-layer coating film, make a toning test coated plate, and apply the obtained toning test coated plate It is necessary to continue the operation of colorimetry and / or colorimetry with the area around the repaired part by a colorimeter until a multi-layer coating film of the desired color is obtained.
For this reason, in automobile repair painting, there has been a demand for a method capable of performing highly accurate color measurement in a shorter time in order to standardize the color matching work and improve productivity by shortening the color matching time.

Multicolor coating toning test coated plate, in particular, for the colorimetry of the multicolor coating test coating plate having a clear coating on the colored coating, the color measurement without the clear coating or In the case where a material different from the actually used clear coating film is applied or pasted, for example, there is a problem that the colorimetric value differs from the actual color of the multilayer coating film.
In particular, in the case of a multi-layer coating having a colored coating formed by a glitter paint such as a metallic paint containing a glitter pigment, the color tone of the color coating only as a single film and the color tone when the multilayer coating is formed. Since the difference is remarkable, it is difficult to perform high-precision colorimetry unless colorimetry is performed in the state of a multilayer coating film having a clear coating film actually used.

At the repair coating site, a two-component urethane tank paint composed of a main agent and a curing agent is often used as a clear paint for obtaining a clear coating film.
In preparing such a two-part urethane rear paint, the main agent and the curing agent must be accurately measured and mixed with each other, and furthermore, baking and curing take time, requiring much labor and time. It has become.
In particular, when a large number of toning test coated plates having a multi-layer coating film are produced, the process of baking and curing the multi-layer coating film (and the step of cooling thereafter) requires a lot of time, so that the toning time is shortened. In order to improve the productivity by the method, the step of baking and curing the multilayer coating film may be omitted.

However, in the case of a multilayer coating film having a colored coating film formed by a glittering paint such as a metallic paint containing a glittering pigment, if the clear coating film is not sufficiently dried, the solvent remaining in the coating film causes a mixed layer. , And unevenness of the bright pigment such as an aluminum pigment or the like may occur, and the finished appearance may be deteriorated, so that an accurate colorimetric value cannot be obtained.
Also, if the color of the coated plate (toning test coating plate) is measured using a contact type colorimeter after the clear coating is applied and the clear coating film is not dried, the wet coating adheres to the colorimeter and becomes dirty. It takes time to clean the colorimeter and the volatile components remaining in the undried coating film will deteriorate the parts of the colorimeter. It is impossible to perform colorimetry stably.

A method of measuring the color of a coated plate (toning test coated plate) with a clear coating film in an undried state using a non-contact type colorimeter is also conceivable. A device is required, and if such a device is not used, there is room for improvement in the accuracy of colorimetry such that measurement conditions are not constant.
In addition, there is still a problem of deterioration of the components of the colorimeter due to volatile components, and if the colorimeter is accidentally brought into contact with the undried coating film, the components become soiled, causing problems such as cleaning.
Under such circumstances, the following proposals have been made so far.

  Patent Document 1 discloses, as a method for reducing the time required for preparing a toning test coated plate, when comparing a metallic coated surface A after toning with a metallic coated surface B of a target color, the coated surface A is coated with an organic solvent. There is disclosed a toning determination method in which the toner is wetted in advance. According to this toning determination method, the gloss of the metallic paint surface can be made to have an appearance as if the clear paint was overcoated without taking time, but depending on the target color, the value measured by the colorimeter and the actual value may be used. In some cases, there is a deviation from the color, and it is not possible to obtain a toning coating composition with high accuracy. In addition, there is a concern that the contamination of the colorimeter and the effect of the organic solvent on the colorimeter may occur.

  Patent Document 2 discloses a method in which a liquid that does not dissolve the color paint film is applied on the color paint film that has been touch-dried, and a colorless transparent solid paint film such as a solid clear paint is applied thereon. A method for measuring the color of a colored paint film including a method of placing a thin film and measuring the color of the colored paint film via the thin film is described. However, when such a method is used for a metallic toning coating film, there is a possibility that a deviation occurs between a value measured by a colorimeter and an actual color. In addition, there is a problem that it is not possible to control the “color unevenness” generated in the metallic toning coating film by mounting the thin film, and it is not possible to obtain an accurate colorimetric value.

  Patent Literature 3 discloses (1) a step of forming a toned colored wet film having a constant film thickness by applying a colored liquid for toning on the surface of a colorimetric substrate by a coating method except spray coating; (1A) a step of drying the formed toned colored wet film to form a toned colored dry film, if necessary; and (2) forming the formed colored wet film or drying as necessary. A step of applying a transparent liquid to the surface of the colored dry film thus formed by a coating method except spray coating to form a transparent wet film having a constant thickness, and (2A) drying the formed transparent wet film as necessary (3) measuring the color of the surface of the transparent wet film or the transparent dry film with a colorimeter, and (4) toning measured by the above (3). Color measurement and required color sample samples (5) The difference between the color for toning and the color of the sample is small due to the process of (4) above, and there is no need for toning of the colored liquid. When it is determined that the toning ends, and when it is determined that the difference is large and that the toning of the colored liquid is necessary, the steps (1) to (4) are repeated once or a plurality of times. A step of performing toning until the difference between the toning color and the color of the sample is small and it is determined that toning of the coloring liquid is not necessary. A toning method using a liquid having a predetermined apparent viscosity range and a predetermined viscosity (structural viscosity index) range as a toning colored liquid to be coated on the surface is described.

  This toning method does not use spray coating as a means for applying a colored paint. Therefore, when the actual coating means is spray coating, there is a problem that color correlation is poor and toning is difficult. Further, since the color is measured after forming the transparent dry film by heating (at 140 ° C. for 20 minutes) after applying the clear paint, it is possible to shorten the working time including the heating time and the cooling time. There is a problem in terms of improving productivity.

  Patent Document 4 discloses an apparatus for measuring the color of a liquid film before drying and curing in order to control the color of a coating material, and a liquid for forming a liquid film having a constant thickness on the surface of a liquid film forming substrate. A film forming means, and a color measuring means for performing color measurement without contacting the liquid film at a position close to the surface of the liquid film, and these are arranged adjacent to each other, and a liquid film forming A transfer means for transferring the substrate for liquid film formation from the means to the colorimetric means, and the colorimetric means is provided with a positioning means for determining an interval between the measurement surface and the surface of the liquid film. The liquid film formation and colorimetry are performed while holding the liquid film formation substrate on the transfer means, and the liquid film formation substrate is provided with a liquid for forming a coating film. It has a flat surface on which the material is supplied and is arranged horizontally, and as the liquid film forming means, along the surface of the liquid film forming substrate. Relative movement, the liquid film for colorimetric apparatus characterized in that it comprises a scraping member, is described.

This apparatus is capable of performing high-precision colorimetry on a liquid film, which is a coating film that has not been dried, using not only a non-contact colorimeter but also a contact colorimeter. However, the configuration of the apparatus is complicated, and the colorimetric operation is complicated.
Further, there is no description that it is effective for a multilayer coating film having a colored coating film formed by a glitter paint such as a metallic paint containing a glitter pigment. Furthermore, a marked difference may occur in the color tone and unevenness between a colored coating film made of a metallic paint containing a glitter pigment and a multilayer coating film provided with a clear coating film on the colored coating. Therefore, if colorimetry is not performed in the state of a multi-layer coating film with a clear coating film, high-precision color measurement can be performed, especially on painted plates with metallic multi-layer coating films (toning test coating plates). May not be.
Furthermore, since a spray coating apparatus is not used, there is a problem that when the actual coating means is spray coating, the color correlation is poor and the toning is difficult.

  Patent Documents 5 and 6 disclose that when a colorimetric operation is performed on a colorimetric object by an integrating sphere spectrophotometer, a mask member is pressed against the colorimetric object to perform colorimetry. ing. The mask member is also referred to as a target mask or the like, and a mask main body is provided with a window for defining the size of a color measurement target area (color measurement target area) of the color measurement target. And a mounting portion is provided, and the mask member is detachable from the colorimeter by the mounting portion.

However, the integrating sphere spectrocolorimeters described in Patent Documents 5 and 6 are formed of a brilliant paint such as a metallic paint containing a brilliant pigment of an automobile which has a different hue and brightness depending on the viewing angle due to the brilliant material. It is not usually used for colorimetry of a multilayer coating film having a colored coating film. Further, Patent Documents 5 and 6 disclose and suggest that the technology relating to such an integrating sphere spectrophotometer is applied to a multi-angle multi-angle spectrophotometer having a different color measurement mechanism. It is difficult from the viewpoint of common technical knowledge.
Further, details of the material and thickness of the mask member are not clear, and there is a risk that volatile components remaining in the undried coating film may deteriorate parts of the colorimeter, A deviation may occur between the value measured by the color meter and the actual color.
In addition, when the mask member is brought into contact with the undried coating film to measure the color, it takes time to clean the mask member having a complicated structure, and a plurality of expensive mask members are required, which is disadvantageous in cost. Or other problems.

JP-A-9-178559 JP 2001-336981 A JP 2004-305987 A JP-A-4-370721 JP-A-2006-90537 JP-A-2015-215239

  An object of the present invention is to solve the various problems described above, a color coating film with a coloring paint, and a clear coating film with a clear paint, in a colorimetric method of a coated plate having a multilayer coating film including, An object of the present invention is to provide a method for measuring the color of a coated plate, which can perform colorimetry of a multi-layer coating film equivalent to that of an actual repairing process easily and accurately in a short time without soiling a colorimeter. .

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and found that the following structure can solve the above-mentioned problems, and have completed the present invention.
Specifically, it is as follows.
Item 1: A colorimetry method for a coated plate having a multilayer coating film including a colored coating film with a colored paint and a clear coating film with a clear paint,
(1) a step of applying a colored paint to form a colored coating film;
(2) a step of applying a clear paint on the colored coating to form a clear coating;
(3) Within 5 minutes after the formation of the clear coating, the protective sheet having at least the colorimetric area of the coating plate opened between the surface of the clear coating and the colorimeter. A step of measuring the color from the surface of the clear coating film using a colorimeter,
A method for measuring the color of a painted plate, including:

Item 2: A colorimetry method for a coated plate having a multilayer coating film including a colored coating film using a coloring paint and a clear coating film using a clear coating,
(1) a step of applying a colored paint to form a colored coating film;
(2) a step of applying a clear paint on the colored coating to form a clear coating;
(3) In a state where at least a protective sheet having a colorimetric area of the coating plate opened is present between the surface of the clear coating film that is not completely dried and the colorimeter, the clear coating is performed. A step of measuring the color from the surface of the film using a colorimeter,
A method for measuring the color of a painted plate, including:

Item 3: The colorimetric method for a coated plate according to Item 1 or 2, including a step of placing the clear coating film formed in the step (2) at a temperature of 15 to 80 ° C.
Item 4: The colorimetric method for a coated plate according to any one of Items 1 to 3, which includes a step of setting the solid content of the clear coating film to 40 to 100% by mass.
Item 5: The colorimetric method for a coated plate according to any one of Items 1 to 4, wherein the clear coating is a urethane-curable coating containing a hydroxyl group-containing compound and a polyisocyanate compound.
Item 6: The method for measuring a color of a coated plate according to any one of Items 1 to 5, wherein the glass transition temperature of the clear coating film after drying is 50 ° C. or higher.
Item 7: The colorimetric method of a coated plate according to any one of Items 1 to 6, wherein the dry film thickness of the clear coating film is in the range of 10 to 50 µm.

Item 8: the step of forming a colored coating includes at least one of a step of forming a colored coating by spray coating, a step of setting the colored coating, and a step of preheating the colored coating. Item 8. The colorimetric method for a coated plate according to any one of Items 1 to 7.
Item 9: The colorimetric method for a coated plate according to any one of Items 1 to 8, wherein the thickness of the protective sheet is in the range of 10 to 200 µm.
Item 10: The method for measuring a color of a coated plate according to any one of Items 1 to 9, wherein an adhesive layer is provided on at least one surface of the protective sheet.
Item 11: A toning method using the color measurement method for a coated plate according to any one of Items 1 to 10, wherein the colored paint is mixed with a material containing one or more pigments to achieve a target color. A toning test coated plate coated with the toning paint, and measuring the color by the colorimetry method to determine whether or not the toning mix of the toning paint is acceptable.

  Unless otherwise specified, “drying” in the present specification includes not only drying by volatilization of a volatile solvent (such as a state in which fluidity is lost) but also curing and drying by progress (completion) of a curing reaction. I do.

  According to the colorimetry method of the present invention, in a colorimetry method for a coated plate, colorimetry can be performed using an existing colorimeter, and the colorimeter can be measured from volatile components and stains due to adhesion of undried paint. The colorimetric method can be protected, and anyone can easily use the present colorimetric method, thereby shortening the toning time and the colorimetric work time. Further, the protective sheet used in the present method is not an auxiliary member having an expensive and complicated structure, but a member that is relatively inexpensive and can be replaced or disposable, and can easily protect the colorimeter.

  In addition, the present method takes into account even if the obtained coating film is a multi-layer coating film including a glitter coating containing a glitter paint containing a glitter pigment whose colorimetric data is likely to be blurred under the influence of, for example, muramura. Because of this design, it is possible to accurately measure the color of a multi-layer coating film equivalent to the actual repairing process in a short time, regardless of the coating color.

In particular, in automotive refinish painting using a color sensor and a computer using a computer toning method, a material containing one or more kinds of coloring paints is mixed to determine the success or failure of the toning composition of the toning paint toned to the target color. For the determination, there is provided a method for measuring the color of a coated plate which is suitable as a method for measuring the color of a toned test coated plate.
And, by using such a color measurement method for a coated plate, it is possible to perform high-precision color measurement in a short time, and it is possible to accurately and quickly determine whether or not the toning compound of the toning paint is acceptable. Therefore, it is also possible to standardize the toning work, and in particular, to significantly reduce the toning time.

It is a figure which illustrates one Embodiment of the protection sheet used by this invention. It is a figure which illustrates one embodiment of the color measurement state by the color measurement method of the coated plate of this invention. It is a figure which illustrates one embodiment which attached the protective sheet of the present invention to the colorimeter.

Hereinafter, the present invention will be described in detail.
<1. Colorimetry>
[1.1 Colored paint; Colored coating film]
As the colored paint used in the colorimetry method of the coated plate of the present invention, a colored paint widely used in the paint field can be used without limitation, and one-pack type, two-pack type, aqueous, non-aqueous, and photocurable , Light and thermosetting properties.
For example, it is used when forming a multilayer coating film used for an outer panel of an automobile body such as a car, a truck, a motorcycle, a bus, etc .; an automobile part; an outer panel of a home electric appliance such as a mobile phone and an audio device; Colored paints used for repairing these damaged portions and those used for repairing these damaged portions can be widely used.

Examples of the colored paint in the present invention include a solid color paint, a metallic paint, and a light interference paint.
Further, such a colored paint may be a toned paint which is mixed with one or more kinds of colored paints and toned to a target color.
Materials contained in the coloring paint include coloring agents such as binders / binders (resins, curable compounds, etc.), coloring pigments or pastes thereof, glittering pigments or pastes thereof, gloss modifiers, dispersing (auxiliary) agents, and the like. One or more of the components that are commonly known as components of a colored coating, such as an agent, can be mentioned.
As these colored paints, various commercial products such as "Retan PG Hybrid Eco" and "Retan WB Eco EV" manufactured by Kansai Paint Co., Ltd. can also be used.

The color of the coloring paint may be black, white, red, green, yellow, blue, or purple, or a desired color may be obtained by arbitrarily combining these colors. Examples of the coloring paint include a paint containing at least one of an inorganic coloring pigment, an organic coloring pigment, and a glitter pigment as a coloring pigment.
Among them, brilliant pigments include flaky metal pigments such as aluminum, copper, chromium, nickel alloy, and stainless steel, flaky metal pigments whose surfaces are coated with a metal oxide, and flakes on which color pigments are chemically adsorbed or bonded. And / or light interference pigments such as metal oxide-coated mica pigments, metal oxide-coated alumina flake pigments, metal oxide-coated glass flake pigments, metal oxide-coated silica flake pigments, etc. , Etc., one or more of glittering pigments can be used.

[1.2 Clear paint; clear coating film]
As the clear paint used in the colorimetry method of the coated plate of the present invention, a clear paint widely used in the paint field can be used without limitation, and one-pack type, two-pack type, aqueous, non-aqueous, and photocurable , Light and thermosetting, volatile paints (such as lacquers) and the like.
Further, the clear paint may be a top clear paint used for the uppermost layer, or may be a clear paint that forms a clear coating film in which a coating film is further provided on the clear coating film.

As the clear paint, a completely colorless and transparent paint can be used, and a color clear paint that is colored within a range in which the coating film can maintain a clear state may be used.
Among them, when forming a multilayer coating film used for an outer panel of an automobile body such as a passenger car, a truck, a motorcycle, a bus, etc .; an automobile part; an outer panel of a household electric appliance such as a mobile phone and an audio device; Clear paints used for repairing these damaged parts and clear paints used for repairing these damaged parts can be widely used.

  As such a clear paint, preferably, a lacquer-type clear paint capable of forming a dry film by removing a volatile solvent, a curable clear paint capable of forming a dry film by mixing a main agent and a curing agent Are used.

  Lacquer type clear paint that can form a dry coating film by removing a volatile solvent may be an aqueous lacquer containing water as a volatile solvent, or a non-aqueous lacquer containing an organic solvent as a volatile solvent. Good.

The curable clear paint that can form a dry coating film by mixing the main agent and the curing agent may be a one-pack paint or a multi-pack paint such as a two-pack paint, an aqueous paint, Any of non-aqueous paint, powder paint, aerosol paint and the like may be used.
Particularly preferably, a urethane-curable paint containing a hydroxyl group-containing compound and a polyisocyanate compound is used.

  Any compound having two or more hydroxyl groups can be used as the hydroxyl group-containing compound. For example, ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, tetraethylene glycol, triethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2 -Butanediol, 3-methyl-1,2-butanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,2-pentanediol, 1,5-pentanediol, 1,4-pentanediol 2,4-pentanediol, 2,3-dimethyltrimethylene glycol, tetramethylene glycol, 3-methyl-4,3-pentanediol, 3-methyl-4,5-pentanediol, 2,2,4-trimethyl -1,3-pentanediol, 1,6-hexanedi Polyol, low molecular polyol compounds such as diols such as 1,5-hexanediol, 1,4-hexanediol, 2,5-hexanediol and neopentyl glycol, and triols such as glycerin; acrylic polyols, polyether polyols and polyesters Polymer polyols such as polyols, polyurethane polyols, polycarbonate polyols and epoxy polyols; and the like.

These hydroxyl group-containing compounds may be used alone or in combination of two or more.
The hydroxyl value of the hydroxyl group-containing compound and the weight average molecular weight of the polymer polyol may be suitably selected from the viewpoints of cross-link density, scratch resistance, water resistance, acid resistance, smoothness, and the like.
The preferred hydroxyl group-containing compound in the clear coating used in the present invention is at least one kind of polymer polyol, particularly preferably one or more of acrylic polyol, polyester polyol and polyether polyol, more preferably acrylic polyol. is there.

  As the polyisocyanate compound, any compound having at least two isocyanate groups in one molecule can be used. For example, aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; cycloaliphatic diisocyanates such as hydrogenated xylylene diisocyanate, isophorone diisocyanate and cyclohexane diisocyanate; araliphatic diisocyanates such as xylylene diisocyanate; Aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate; triphenylmethane-4,4 ', 4' '-triisocyanate, 1,3,5-triisocyanatobenzene, 2,4,6-triisocyanato Polyisocyanate compounds having three or more isocyanate groups such as toluene and 4,4'-dimethyldiphenylmethane-2,2 ', 5,5'-tetraisocyanate It can be mentioned derivatives of the polyisocyanate; polyurethane polyisocyanate, polyether polyisocyanates, polymeric polyisocyanates polyester polyisocyanate.

Examples of the derivative of the polyisocyanate include multimers such as dimers and trimers of the above-described polyisocyanate, biuret, allophanate, uretdione, uretimine, isocyanurate, oxadiazinetrione, polymethylene polyphenyl polyisocyanate (crude MDI, polymeric MDI), crude TDI, and the like.
Further, as the polyisocyanate compound, a blocked polyisocyanate compound which is a compound obtained by blocking an isocyanate group in the above-mentioned polyisocyanate and its derivative with a blocking agent can also be used.
These polyisocyanate compounds and derivatives thereof may be used alone or in combination of two or more.

  A solvent such as water or an organic solvent, and additives such as a curing catalyst, an antifoaming agent, and an ultraviolet absorber can be appropriately added to the clear coating material, if necessary.

The glass transition temperature of the dried clear coating film is preferably adjusted to 50 ° C. or higher from the viewpoint of improving the colorimetric workability. The glass transition temperature is preferably from 60 to 100C, more preferably from 60 to 80C.
The glass transition temperature of the clear coating film of the present invention can be measured, for example, using an FT rheology spectrometer “Rheogel E-400” (manufactured by UBM) at a frequency of 110 Hz and a heating rate of 4 ° C./min. Is the dynamic glass transition temperature measured as the temperature at which the maximum value of tan δ (loss modulus / storage modulus) is measured in dynamic viscoelasticity measurement. The sample was prepared by applying the clear composition used in the present invention on a polypropylene plate so as to have a dry film thickness of 25 μm, forming a dry film under drying conditions of 80 ° C. for 20 minutes, and then obtaining the dry film obtained. Is peeled off from the polypropylene plate as a free coating film, and cut into a strip having a length of 20 mm and a width of 5 mm at a portion where there is no end portion, no defect, or the like, to obtain a sample.

  In the present invention, when a urethane-curable paint containing a hydroxyl group-containing compound and a polyisocyanate compound is used as a clear paint and a toning test coated plate is produced, the toning test coated plate is formed in an actual repair coating process. This is particularly preferable because a multilayer coating film having characteristics very similar to those of the multilayer coating film can be formed. Highly accurate colorimetry can be performed because it is almost equivalent to the colorimetry after actual repair coating.In addition, the produced toning test coated plate is protected by a clear coating film with urethane cross-linking, so it is waterproof. It is excellent in properties, reduces discoloration and deterioration (such as film loss) due to aging, and makes it possible to reuse a painted plate as a color sample plate.

In one embodiment of the present invention, at least 5 minutes after the formation of the clear coating film, the protective sheet having at least the colorimetric gamut of the coated plate opened between the surface of the clear coating film and the colorimeter. Within, preferably within 3 minutes, more preferably within 1 minute, the color is measured from the surface of the clear coating film using a colorimeter.
Therefore, even when the color measurement is performed in such a manner by adjusting the composition of the clear paint, it is necessary that the clear paint be provided with at least a characteristic that does not cause unevenness.

Further, in one embodiment of the present invention, at least the protective sheet in which the colorimetric area of the painted plate is opened is present between the surface of the clear coating film that is not completely dried and the colorimeter. In this state, the color is measured from the surface of the clear coating film using a colorimeter.
Therefore, even when the color measurement is performed in such a manner by adjusting the composition of the clear paint, it is necessary that the clear paint be provided with at least a characteristic that does not cause unevenness.

In the method for measuring the color of a coated plate of the present invention, the clear coating film formed by applying the clear paint may be placed at a temperature of 15 to 80 ° C. from after the clear paint is applied until the color measurement.
The clear coating film formed by applying the clear paint has a solid content of 40 to 100% by mass, preferably 40 to 99% by mass, more preferably 45 to 90% by mass at the time of color measurement. It may be.
The clear paint film provided by applying the clear paint is placed at a temperature of 15 to 80 ° C. from after the clear paint is applied until color measurement, and the solid content of the clear paint film at the time of color measurement is 40 to 80 ° C. It may be 100% by mass.

As a means for adjusting the solid content of the clear coating film at the time of color measurement to 40 to 100% by mass, an appropriate coating film drying means such as a heating means may be used if necessary.
Here, the time for setting the solid content of the clear coating to 40 to 100% by mass is not particularly limited, but is not more than 5 minutes, preferably not more than 3 minutes, more preferably not more than 1 minute after the formation of the clear coating. It is preferable to adjust the time by adjusting the components of the clear paint.

Also, by applying a clear paint and setting and / or heating as necessary, the solid content of the obtained clear coating film may be 40 to 100% by mass, but energy saving, low cost, and safety are achieved. From the viewpoints of workability, workability, and the like, it is preferable to be able to start colorimetry under lower temperature and shorter time conditions.
When the solid content of the clear coating film is less than 40% by mass, unevenness occurs, or the clear coating film reaches the colorimeter through the opening of the protective sheet and stains the colorimeter. In addition, there is a possibility that a volatile component such as an organic solvent contained in the clear coating film affects the colorimeter, and the like.
When the solid content of the clear coating film is to be more than 90% by mass, particularly more than 99% by mass, it takes too much time from the formation of the clear coating film to the measurement of the color if it is a usual clear coating material. In addition, when a clear coating film is to be obtained by forcibly drying at a high temperature (for example, exceeding 80 ° C.) to obtain a clear coating film, it is necessary to form a multilayer coating film having a uniform coating film with excellent color stability. May be difficult.

In this specification, the solid content (mass%) of the clear coating film at a predetermined point in time is determined by the following formula, and is the solid content of the paint applied to the object (coated NV). It is also called.
Solid content of clear coating film = (m ₂ −m ₀ ) / (m ₁ −m ₀ ) × 100
m ₀ : mass (g) of the object before painting
m ₁ : mass (g) of the coated object at a predetermined time
m ₂ : mass (g) of a coated product having a dry coating film in which the solvent was completely volatilized

  The dry film thickness of the clear coating film is not particularly limited, but is usually in the range of 10 to 50 μm, preferably 20 to 40 μm, and more preferably 25 to 35 μm.

[1.3 Coating means; coating film forming method]
As a coating means and a coating film forming method used in the colorimetry method of the coated plate of the present invention, a coating method widely used in the field of coatings can be used without limitation.
Examples of means for applying a colored paint and / or a clear paint used in the colorimetry method of the coated plate of the present invention include air spray, airless spray, electrostatic spray, rotary atomization, brush coating, roller coating, ink jet, One or more means such as aerosol, immersion, and the like can be used, and a single coating or a plurality of coatings may be performed.
As a preferable coating means, spray coating such as air spray, airless spray, electrostatic spray, and rotary atomization is used.

When applying a colored paint on a substrate, if the substrate is contaminated with a contaminant (oil, etc.), it is preferable to degrease and clean using a solvent such as alcohol. If is clean, degreasing and cleaning need not be particularly performed.
In order to enhance the adhesion and adhesion between the substrate and the coating film, the substrate may be subjected to a surface treatment such as a surface roughening treatment, a plasma treatment, a flame treatment, and a primer treatment.

  After applying the colored paint or the clear paint, setting (standing) and / or preheating can be performed. The setting is usually carried out by allowing the device to stand at room temperature, and the heating temperature, heating time, and the like for preheating can be arbitrarily set. In some cases, forced drying using a blower or the like may be performed.

As the base material of the coated plate, a base material usually used when manufacturing a coated plate can be used, and various metal plates, plates of inorganic materials such as glass, various plastic plates, paper plates, and the like can be used. Preferably, a metal plate is used.
The base material of these coated plates may have been subjected to a surface treatment such as a phosphate treatment, a chromate treatment, a plating treatment, a composite oxide treatment, an electrodeposition coating treatment, a primer treatment, and a degreasing treatment.

[1.4 Colorimeter; Step of Color Measurement]
The colorimeter used in the method for measuring the color of a coated plate of the present invention includes colorimeters that are widely used for color management and / or color measurement of industrial products having colors on the surface. Can be used. For example, an integrating sphere spectrophotometer, a multi-angle spectrophotometer and the like are mentioned, but not particularly limited.
Preferably, in order to be able to cope with the color measurement of a glittering coating film (metallic coating film), light is incident from one direction in one measurement and received at multiple angles of 3 to 6 angles (for example, 25 °, 45 °, 75 °) can be used.
In particular, a multi-angle spectrophotometer "AI color sensor" manufactured by Kansai Paint Co., Ltd. and a multi-angle spectrophotometer "Tri-COLOR" manufactured by BYK Japan are preferably used.

In the present invention, by using such a colorimeter, values of L ^* indicating lightness and chromaticities a ^* and b ^* indicating hue and saturation in the L ^* a ^* b ^* color space are obtained. Can be. Then, the color difference from the target color can be quickly measured using these values.
Here, the L ^* a ^* b ^* color space is a color system most commonly used in all fields at present to represent the color of an object. In 1976, the International Commission on Illumination (CIE) JIS (JIS Z 8781-4, Z 8781-5).
In the L ^* a ^* b ^* color space, chromaticities a ^* and b ^* indicating hue and saturation indicate a color direction, a ^* is in a red direction, -a ^* is in a green direction, and b ^* is in a green direction. The yellow direction and -b ^* indicate the blue direction. The color becomes vivid when the absolute value of the numerical value increases, and becomes dull when the absolute value of the numerical value decreases. L ^* indicating lightness takes a numerical value from 0 to 100, where L ^* = 100 is white and L ^* = 0 is black.

  In one embodiment of the present invention, at least 5 minutes after the formation of the clear coating film, the protective sheet having at least the colorimetric gamut of the coated plate opened between the surface of the clear coating film and the colorimeter. Within, preferably within 3 minutes, more preferably within 1 minute, the color is measured from the surface of the clear coating film using a colorimeter.

  Further, in one embodiment of the present invention, at least the protective sheet in which the colorimetric area of the painted plate is opened is present between the surface of the clear coating film that is not completely dried and the colorimeter. In this state, the color is measured from the surface of the clear coating film using a colorimeter.

Here, the clear paint film provided by applying the clear paint is referred to as "a state that is not completely dried", and refers to a state where drying of the clear paint film is not completely finished by heating for a long time or the like. . That is, in the case where the clear paint is a lacquer type clear paint containing no curing agent, a state in which the volatile solvent (water, organic solvent, etc.) in the clear paint is not completely volatilized is mixed with the main agent and the curing agent. In the case of a curable clear coating, it refers to a state in which dry curing (crosslinking) is not completely completed.
In general, a state other than the “cured and dried” state specified in JIS K 5600-1-1 (1999), that is, “a center of a painted surface is strongly sandwiched between a thumb and an index finger, and a fingerprint is applied to the painted surface No dent is formed, no movement of the painted surface is felt, and the state is not a state in which the center of the painted surface is rapidly and repeatedly rubbed with a fingertip to leave no rub marks on the painted surface.

  As such a state, for example, a "touch dry state" (a state in which the center of a painted surface is lightly touched with a fingertip and the fingertip is not stained) or a "half-touch state" defined in JIS K 5600-1-1 (1999). Cured and dry state "(a state in which the center of the coated surface is gently and lightly rubbed with a fingertip so that no rub marks are formed on the coated surface).

[1.5 Protective sheet]
The protective sheet used in the method for measuring the color of a coated plate of the present invention is one that exists between the surface of the clear coating film on the coated plate and the colorimeter at the time of color measurement of the coated plate, and at least. The colorimetric gamut of the painted plate is open.
The opening provided in the protective sheet may have any shape as long as it opens at least the colorimetric gamut of the painted plate, and may have, for example, a circular or square shape. As long as the desired effect can be obtained, it may be larger than the colorimetric gamut.
The openings in the protective sheet correspond to the colorimeters (sensor windows, openings, etc.) provided in the colorimeter main unit, which allows the light from the light source of the colorimeter to flow directly to the painted plate. Irradiation becomes possible.

The protective sheet is present between the clear coating film and the colorimeter, and functions to prevent such a clear coating film from adhering to the colorimeter and contaminating the colorimeter. It has a function of preventing the colorimeter from being deteriorated or damaged by the organic solvent volatilized from such a clear coating film.
If the protection sheet becomes contaminated, the protection sheet is relatively inexpensive and can be discarded, and replacement is easy.
Furthermore, since at least the colorimetric area of the painted plate is open and the opening is compatible with the colorimetric section (sensor window, opening, etc.) provided in the colorimeter main body, the actual It has a function to measure the color by directly irradiating the light from the light source of the colorimeter to the multilayer coating film.

The shape or the like of the protective sheet is not particularly limited as long as the opening is provided, and may have other openings, cuts, and the like as long as the intended function is not impaired. Further, at least a part of the sheet may be formed into a desired shape by bending or forming. In consideration of cost and the like, a flat sheet-like one having only a colorimetric gamut of the painted plate is preferable.
In particular, a sheet-like material has high versatility, can be easily processed into a desired shape as needed, and can be easily applied to various colorimeters.

The protective sheet may have any thickness, but is usually from 10 to 200 μm, preferably from 20 to 150 μm, and more preferably from 30 to 120 μm.
If the thickness is less than 10 μm, the protective sheet may be difficult to handle, may be easily damaged, or may not be able to prevent the influence of the solvent in the clear coating film on the colorimeter.
If the thickness is more than 200 μm, light may be taken in from the surroundings and accurate colorimetry may not be performed, or the colorimetric value may be different from the actual color of the multilayer coating film.

Examples of the material constituting the protective sheet include polyester resin, polyolefin resin, polyamide resin, polystyrene resin, acrylic resin, vinyl chloride resin, fluorine resin, cellulose resin, polyvinyl alcohol resin, and vinyl acetate resin. Resins such as resins, polycarbonate resins and polyurethane resins, and various plastic materials such as FRP; metal materials such as aluminum foil, stainless steel foil and copper foil; Western paper (high quality paper, coated paper, tracing paper, etc.), Japanese paper (Straw paper, paper, etc.), cooking sheets, cellophane and other paper materials; woven fabrics, nonwoven fabrics, knitted fabrics and other fiber materials; and glass, wood and other arbitrary materials.
In the present invention, a composition containing two or more of these may be used, or a laminate having a layer containing one or more of these may be used.

In the present invention, at least a part of at least one surface of the protective sheet may have an adhesive layer. The adhesive layer may be on only one side or on both sides, but is preferably on one side. The adhesive layer may be provided on at least one entire surface of the protective sheet, or may be provided partially in a desired shape or the like.
Examples of the protective sheet provided with such an adhesive layer include an adhesive sheet or an adhesive tape having an adhesive layer on at least one surface of a plastic sheet (film), paper, metal, or the like (for example, a polyolefin resin adhesive). Film, polyester resin pressure-sensitive adhesive film, and paper-based pressure-sensitive adhesive sheet such as Post-It (registered trademark)).

As the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer, an arbitrary pressure-sensitive adhesive such as an acrylic, rubber, silicone, or urethane-based adhesive can be used. These pressure-sensitive adhesives are used for secure fixing, influence on the colorimeter (prevention of adhesive residue at the time of peeling, prevention of detachment of parts of the colorimeter at the time of peeling, prevention of malfunction of the colorimeter by the adhesive, etc.) An appropriate one can be selected based on the viewpoint.
Due to the presence of the adhesive layer, the protective sheet can be securely fixed to the colorimeter and / or the painted plate, and colorimetry can be easily and accurately performed continuously. By using the method, the protective sheet can be easily removed without affecting the colorimeter or the painted plate.
Further, for example, a double-sided tape may be attached to a colorimeter and / or a protective sheet in advance, and the protective sheet may be fixed to the colorimeter and / or the painted plate with a double-sided adhesive tape.
In the present invention, in terms of durability to organic solvents used in the clear paint, cost, influence on the colorimeter, etc., as a protective sheet, preferably, a polyester resin film, a polyolefin resin film, paper, one side A polyester resin film provided with an adhesive layer, a polyolefin resin film provided with an adhesive layer on one side, and paper provided with an adhesive layer on one side (for example, Post-it (registered trademark)) can be used.

<2. Toning method>
The toning method of the present invention is characterized in that: A method for toning using a colorimetry method for a coated plate, wherein the colored paint is a toned paint mixed with a material containing one or more pigments and toned to a target color. Is a color toning test method comprising the steps of: measuring the color of a coated toning test coated plate by the above color measuring method, and determining whether or not the toning compound of the toning paint is acceptable.
1. The method for measuring the color of a coated plate is not to measure after heating after forming a multilayer coating film, drying completely, and then cooling. Therefore, in a toning method using a computer toning method, a coating plate (toning test coating plate) prepared for each of a plurality of types of toning paints toned to a target color can be continuously and rapidly improved. Color measurement can be performed with high accuracy.

  1. The color toning method of the present invention using the method for measuring the color of a painted plate is not an auxiliary member having an expensive and complicated structure, but is a colorimeter using a member which can be easily replaced and disposable with a relatively inexpensive member. Can be protected. In addition, the toning work can be standardized, the toning time and the color measuring work time can be reduced, and the multilayer coating film equivalent to the actual repair process can be shortened without being affected by irregularities and the like. This is a toning method capable of performing color measurement with high accuracy in a long time and accurately and quickly determining whether or not the toning compound of the toning paint is acceptable.

  In particular, in automobile repair painting using a color sensor and a computer using a computer toning method, a mixture of materials containing one or more types of coloring paints is used to judge the success or failure of the toning of the toning paint toned to the target color. Therefore, it is suitable as a colorimetric method for a toning test coated plate.

  The toning method of the present invention makes it possible to accurately and quickly determine the success or failure of the toning composition of the toning paint based on highly accurate color measurement in a short time. Standardization, in particular, the average number of toning operations in repair work for one vehicle can be reduced from 5 to 2 times, greatly reducing the toning time, for example, toning work per month The time can be reduced by about 60%.

  Hereinafter, the present invention will be described more specifically with reference to specific examples. However, the present invention is not limited to only these examples.

(Preparation of reference plate 1)
Paint SV (manufactured by Kansai Paint Co., Ltd., flaky) on a substrate (tin plate) of 10 cm × 10 cm, which is toned as silver by a computer toning method (computer color matching; CCM) as a colored paint. A urethane-curable coating composition containing an aluminum pigment) is used as a color coating type, and spray-coated so as to obtain a dry film thickness of about 20 μm to form a color coating film. Dry to the touch.
A clear paint C1 (trade name "Retan PG Eco HS (High Solid) Clear (Q)" manufactured by Kansai Paint Co., Ltd.); a hydroxyl group-containing acrylic resin and a polyisocyanate compound having an NCO / OH ratio of 1.2 A spray coating of a urethane-curable clear coating composition having a glass transition temperature (coating Tg) of 55 ° C.) so that the dried coating film has a thickness of 25 μm. I got
The obtained coated plate was set (rested) at 20 ° C. for 5 minutes, and then heated at a temperature of 60 ° C. for 30 minutes to prepare a reference plate 1.

(Preparation of reference plate 2)
Instead of the paint SV, a paint BM (a urethane-curable paint composition containing a flaky aluminum pigment and a color pigment, manufactured by Kansai Paint Co., Ltd.) whose paint color is adjusted to blue metallic by CCM is used as a coloring paint type. A reference plate 2 was produced in the same manner as the method for producing the reference plate 1 except that the colored coating film was formed.

(Preparation of reference plate 3)
Instead of the paint SV, a paint film GS (a urethane-curable paint composition containing a color pigment, manufactured by Kansai Paint Co., Ltd.) whose paint color is toned to a gray solid by CCM is used as a paint material to form a colored coating film. A reference plate 3 was produced by the same method as that for producing the reference plate 1 except that the reference plate 3 was formed.

(Color measurement of reference plates 1-3)
A calorimeter (multi-angle spectrophotometer; Tri-COLOR, manufactured by BYK Japan) is gently placed on the clear coating surface of the reference plates 1 to 3, and three angles (25 ° (highlight), 45 ° ( L ^* a ^* b ^* for each of front (front) and 75 ° (shade) were measured, and the obtained colorimetric data was used as a reference value.
At the time of color measurement, even without using a protective sheet, stable color measurement was possible without sticking the coating film to the colorimeter or, on the contrary, leaving a trace or the like on the coating film.

(Example 1)
A paint film is formed on a base material (tin plate) of 10 cm × 10 cm by spray coating using the paint SV used for the production of the reference plate 1 as a color paint type so as to have a dry film thickness of about 20 μm. did. After leaving to stand at 20 ° C. for 5 minutes and drying by touch, the clear paint C1 used for the production of the reference plate 1 is spray-coated thereon so that the dry paint film becomes 25 μm, and has a multilayer paint film. A painted plate was obtained.
Without setting the coated plate having the obtained multilayer coating film, the temperature condition was set at 60 ° C. after the clear coating, and color measurement was performed by a colorimeter at the time when 5 minutes had passed since the completion of the clear coating. .
Further, at the time of color measurement, the solid content of the clear coating film was measured, the dried state of the clear coating film was evaluated, the colorimetric value was evaluated using a colorimeter, the visual appearance was evaluated, and the colorimetric workability was evaluated. The results are as described in Table 1.

In addition, the color measurement by the colorimeter was performed as follows.
A multi-angle spectrophotometer (BYK Japan Inc.) in which a coated plate having a multi-layer coating film is placed horizontally, and a protective sheet S1 having a predetermined opening is adhered to the surface of the multi-layer coating film of the coating plate with an adhesive. Manufactured by Tri-COLOR Co., Ltd., and in a state where a protective sheet having a predetermined opening is present on the surface of the multilayer coating film, three angles (25 ° (highlight), 45 ° ( The values of L ^* a ^* b ^* for each of front (front) and 75 ° (shade) were measured.

(Examples 2 to 42)
In Example 1, the type of the colored paint, the kind of the clear paint, the target dried film thickness of the clear paint film, the coating film Tg (glass transition temperature) of the clear paint film, the temperature conditions after the clear paint was applied, and the time of completion of the clear paint application , The solid content of the clear coating film, the type of protective sheet, and the thickness of the protective sheet were as described in Table 1, respectively, in the same manner as in Example 1, The measurement of the solid content of the clear coating film at the time point, the evaluation of the dry state of the clear coating film, the colorimetric value evaluation with a colorimeter, the visual appearance evaluation, and the colorimetric workability evaluation were performed. The results are as described in Table 1.

(Comparative Example 1)
A paint film is formed on a base material (tin plate) of 10 cm × 10 cm by spray coating using the paint SV used for the production of the reference plate 1 as a color paint type so as to have a dry film thickness of about 20 μm. did. After leaving it to stand at 20 ° C. for 5 minutes and drying it by touch, it was heated at a temperature of 60 ° C. for 30 minutes without applying a clear paint, thereby producing a coated plate according to Comparative Example 1.
The obtained coated plate was subjected to colorimetry with a colorimeter in the same manner as in Example 1, and colorimetric value evaluation with a colorimeter, visual appearance evaluation, and colorimetric workability evaluation were performed. The results are as described in Table 1.

(Comparative Example 2)
In Example 1, the temperature conditions after the clear paint application and the elapsed time from the end of the clear paint application were as described in Table 1, respectively. The measurement of the solid content of the clear coating film at the time point, the evaluation of the dry state of the clear coating film, the colorimetric value evaluation with a colorimeter, the visual appearance evaluation, and the colorimetric workability evaluation were performed. The results are as described in Table 1.

(Comparative Example 3)
In Example 1, the temperature conditions after the clear paint application and the elapsed time from the end of the clear paint application were set as shown in Table 1, respectively, and the protective sheet was not used at the time of color measurement by the colorimeter. In the same manner as in Example 1, measurement of the solid content of the clear coating film at a predetermined time, evaluation of the dry state of the clear coating film, evaluation of colorimetric values by a colorimeter, visual appearance evaluation, and colorimetric work Sex evaluation was performed. The results are as described in Table 1.

The clear paint types C1 to C6 and the protective sheets S1 to S5 in Table 1 are as follows.
C1: Kansai Paint Co., Ltd. product name "Retan PG Eco HS (High Solid) Clear (Q)"; a hydroxyl group-containing acrylic resin and a polyisocyanate compound in an NCO / OH ratio of 1.2; Urethane-curable clear coating composition C2 having a Tg of 55 ° C .: fast-drying urethane-curable clear coating composition C3 having a glass transition temperature (coating Tg) of 70 ° C .: glass transition temperature of the coating film Urethane-curable clear coating composition C4 having a coating film Tg of 40 ° C .: a lacquer clear coating composition containing a hydroxyl group-containing acrylic resin and containing no curing agent and having a glass transition temperature (coating Tg) of 55 ° C. Product C5: Lacquer clear coating composition C6 containing a hydroxyl group-containing acrylic resin and containing no curing agent and having a glass transition temperature (coating Tg) of 70 ° C .: hydroxyl group-containing acrylic Lacquer clear coating composition having a glass transition temperature (coating Tg) of 40 ° C. containing a resin and containing no curing agent; UV-cut transparent cover film manufactured by A-ONE; thickness: 70 μm; single-sided adhesion S2: Transparent single-sided adhesive sheet film made of polyethylene terephthalate; thickness 100 μm
S3: Polyethylene terephthalate transparent single-sided adhesive sheet film; thickness 110 μm
S4: Transparent single-sided adhesive sheet film made of polyethylene terephthalate; thickness 150 μm
S5: 3M company, strong adhesive post-it (size 75 mm × 75 mm); thickness 110 μm; with single-sided adhesive S6: high quality paper (size 75 mm × 75 mm); thickness 110 μm

  In Table 1, the solid content measurement of the clear coating film, the evaluation of the dry state of the clear coating film, the colorimetric value evaluation with a colorimeter, the visual appearance evaluation, and the colorimetric workability evaluation are as follows. I went.

(Measurement of solid content of clear coating film)
The solid content (% by mass) of the clear coating film at a predetermined point in time was obtained as follows.
A 100 mm × 150 mm × 3.0 mm ABS coated object was weighed to obtain a mass m ₀ (g) of the coated object before coating.
After applying the clear paint on the object to be coated so that the dry coating film has the film thickness shown in Table 1, the coated object is weighed at a predetermined time, and the mass m ₁ (g) of the coated material at the predetermined time. I got
A clear paint is applied on the above-mentioned object so that the dried coating film has a film thickness shown in Table 1, then set (rest) at normal temperature of 20 ° C for 5 minutes, and then placed in a drying oven at a heating temperature of 60 ° C for 30 minutes. And dried by heating to obtain a coated product having a dried coating film. This coating was weighed to obtain a mass m ₂ (g) of the coating where the solvent was completely evaporated.
Using these m ₀ , m ₁ and m ₂ , the above formula;
Solid content of clear coating film = (m ₂ −m ₀ ) / (m ₁ −m ₀ ) × 100
m ₀ : mass (g) of the object before painting
m ₁ : mass (g) of the coated object at a predetermined time
m ₂ : mass (g) of a coated product having a dried coating film in which the solvent completely volatilized
, The solid content (% by mass) of the clear coating film at a predetermined time was calculated.

(Evaluation of dry state of clear coating)
Using the coated plate provided with the multilayer coating film, the dried state of the multilayer coating film was evaluated based on the provisions of JIS K 5600-1-1 (1999).
In the present invention, the relationship with the solid content of the clear coating film was as follows. 5: Cured and dried state (the center of the painted surface is strongly sandwiched between the thumb and the index finger, no dent due to fingerprints is formed on the painted surface, no movement of the painted surface is felt, and the center of the painted surface is rapidly moved with a fingertip. Rubbing repeatedly to leave no rub marks on painted surface.) Solid content of clear coating: 90% by mass or more.
4: Semi-cured and dry state (a state in which the center of the coated surface is gently and gently rubbed with a fingertip to leave no trace of the coated surface). Solid content of clear coat: 75% by mass or more and less than 90% by mass.
3: Touch dry state (a state in which the fingertip is lightly touched with the fingertip at the center of the painted surface and the fingertip is not stained). Solid content of clear coating: 60% by mass or more and less than 75% by mass.
2: Less than dry to the touch (the state where the fingertip is lightly touched to the center of the painted surface with the fingertip and the fingertip is soiled, but the colorimeter can be measured without displacement when the colorimeter is placed). Solid content of clear coat: 50% by mass or more and less than 60% by mass.
1: Less than dry to the touch (the state where the fingertip is lightly touched to the center of the painted surface with the fingertip and the fingertip is soiled, and the colorimeter is misaligned when placed, and it is difficult to measure the color). Solid content of clear coating: 40% by mass or more and less than 50% by mass.
0: Less than touch dry state (uncured state immediately after coating). Solid content of clear coating: less than 40% by mass.

(Evaluation of colorimetric value by colorimeter)
Regarding the coated plate having the multi-layer coating according to Examples 1 to 42 and Comparative Examples 2 and 3 or the coated plate having the colored coating according to Comparative Example 1, a large number The values of L ^* a ^* b ^* at three angles (25 ° (highlight), 45 ° (front), and 75 ° (shade)) were measured by an angle spectrophotometer.

From the colorimetric values of each painted plate and the colorimetric values of the corresponding reference plate made using the same colored paint, each angle (25 ° (highlight), 45 ° (front), 75 ° (shade)) , The color difference ΔE ^* between each coated plate and the reference plate was determined, and the colorimetric value was evaluated based on the following criteria. ：: All ΔE ^* values are 0.8 or less
〇: All ΔE ^* values exceed 0.8 and 1 or less〇−: At least one type of ΔE ^* is 1 or less, and at least one type of ΔE ^* exceeds 1 △: All ΔE ^* values are 1 Over 2 or less ×: at least one ΔE ^* value exceeds 2

(Visual evaluation of appearance)
A coated plate having a multilayer coating according to Examples 1 to 42 and Comparative Examples 2 and 3, or a coated plate having a colored coating according to Comparative Example 1 and a corresponding reference plate manufactured using the same colored paint Were arranged, and the color tone, gloss, and unevenness were visually observed and compared, and evaluated according to the following criteria.
A: The color tone and gloss match well with the reference plate, and no unevenness occurs.
〇: Slight difference in color tone and / or gloss from the reference plate and / or slight unevenness has occurred, but it can be determined that they are substantially the same.
〇-: A slight difference in color tone and / or gloss from the reference plate is observed, and / or unevenness occurs, but there is no practical problem.
Δ: Difference in color tone and / or gloss from the reference plate was observed, and / or unevenness occurred.
X: An extremely noticeable difference in color tone and / or gloss from the reference plate was observed, and / or extremely noticeable unevenness was generated.

(Evaluation of colorimetric workability)
The coated plate having the multilayer coating according to Examples 1 to 42 and Comparative Example 2, or the coating plate having the colored coating according to Comparative Example 1 is placed horizontally, and the multilayer coating or the colored coating of each coated plate is placed. A multi-angle spectrophotometer (Tri-COLOR, manufactured by BYK Japan) in which a protective sheet having a predetermined opening shown in Table 1 is attached to the surface of the film with the adhesive, and a multi-layer coating or coloring is performed. With a protective sheet having a predetermined opening on the surface of the coating film, each of three angles (25 ° (highlight), 45 ° (front), 75 ° (shade)) is measured by a multi-angle spectrophotometer. The workability when L ^* a ^* b ^* was measured to measure the color of the multilayer coating film or the colored coating film was evaluated according to the following criteria.

The coated plate having the multilayer coating film according to Comparative Example 3 is placed horizontally, and a multi-angle spectrophotometer (BYK) in which a protective sheet having a predetermined opening is not attached to the surface of the multilayer coating film of the coating plate. Japan Co., Ltd., Tri-COLOR) is placed, and L ^* a ^* b ^* of each of three angles (25 ° (highlight), 45 ° (front), 75 ° (shade)) is measured by a multi-angle spectrophotometer. The workability when performing color measurement of the multilayer coating film was evaluated according to the following criteria.

：: The colorimeter can be stably installed without any deviation. Further, there is no sticking between the clear coating film or the colored coating film and the colorimeter or the protective sheet.
〇: A colorimeter can be installed and colorimetry can be performed without occurrence of deviation or the like. Although the sticking between the clear coating film and the protective sheet occurs slightly, the clear coating film and the protective sheet can be easily peeled off, and even if the protective sheet is contaminated, it is light and the protective sheet can be reused. .
〇-: A colorimeter can be installed and colorimetry can be performed without occurrence of deviation or the like. Adhesion between the clear coating film and the protection sheet occurs, and the clear coating film and the protection sheet cannot be peeled off, or the protection sheet cannot be reused even if it can be peeled off.
Δ: Unless a colorimeter is installed with care, misalignment occurs and / or sticking between the clear coating film and the protective sheet occurs, and the protective sheet becomes so dirty that it cannot be reused.
×: It is clearly difficult to perform colorimetry, significant deviation occurs when the colorimeter is installed, the colorimeter cannot be installed, or the colorimeter is stained by a clear coating film.

As in the above examples, in the color measurement of a coated plate having a multilayer coating film including a colored coating film with a coloring paint and a clear coating film with a clear coating, a predetermined protective sheet is formed on the surface of the clear coating film. When colorimetry is performed from the surface of the clear paint film using a colorimeter within 5 minutes after the completion of the application of the clear paint in the state where the colorimeter exists between the colorimeter and the colorimeter, the colorimetric value evaluation by the colorimeter In addition, the appearance evaluation by visual observation becomes very excellent, the evaluation of colorimetric workability is also good, and the same colorimetric data as the reference plate can be obtained.
Therefore, it has become possible for the first time to perform highly accurate color measurement in a short time for a multilayer coating film equivalent to the actual repair process.

Further, in the color measurement of a coated plate having a multi-layer coating film including a colored coating film with a coloring paint and a clear coating film with a clear coating, the clear coating film in a state where a predetermined protective sheet is not completely dried. Even when measuring the color of the clear coating film surface using a colorimeter in the state between the surface of the surface and the colorimeter, the colorimetric value evaluation by the colorimeter and the visual evaluation by visual inspection are extremely excellent. The colorimetric workability evaluation was also good, and the same colorimetric data as the reference plate could be obtained.
Therefore, it has become possible for the first time to perform highly accurate color measurement in a short time for a multilayer coating film equivalent to the actual repair process.

Therefore, when a toning test coating plate used for toning is produced using a clear coating (urethane-curable clear coating composition) used in actual repair work and the color is measured, the same duplication as in the actual repair process is performed. It has become possible for the first time to perform highly accurate colorimetry on a layer coating film in a short time.
In particular, when adjusting the repair paint using a computer toning method that has a large number of toning test coated plates and a number of color measurements, it is possible to quickly and accurately determine the success or failure of the toning compounding of the toning paint. Work can be standardized, and the toning work time can be greatly reduced.

Comparative Example 1 is an example having no clear coating film, and it was not possible to evaluate the color tone, gloss, presence / absence of occurrence of unevenness, etc. when a clear coating material used in an actual repair process was applied to form a multilayer coating film. In addition, colorimetric value evaluation by a colorimeter and visual evaluation by visual inspection are poor.
In Comparative Example 2, since the multi-layer coating film (clear coating film) of the coated plate having the multi-layer coating film was substantially in a cured and dried state, both the colorimetric value evaluation and the visual evaluation of the test piece appearance were problematic. However, although the workability is good without sticking of the protective sheet, the productivity is not improved by shortening the work time.
Comparative Example 3 is an example in which the protective sheet was not used. When the colorimeter was placed on the coating film, a shift occurred, and the clear paint adhered to the colorimeter. Was not good.

DESCRIPTION OF SYMBOLS 1 Protective sheet 1-a Opening 1-b Adhesive layer 2 Colorimeter 3 Painted plate

Claims (11)

A color measurement method for a coated plate having a multilayer coating film including a colored coating film with a coloring paint and a clear coating film with a clear coating,
(1) a step of applying a colored paint to form a colored coating film;
(2) a step of applying a clear paint on the colored coating to form a clear coating;
(3) Within 5 minutes after the formation of the clear coating, the protective sheet having at least the colorimetric area of the coating plate opened between the surface of the clear coating and the colorimeter. A step of measuring the color from the surface of the clear coating film using a colorimeter,
A method for measuring the color of a painted plate, including: A color measurement method for a coated plate having a multilayer coating film including a colored coating film with a coloring paint and a clear coating film with a clear coating,
(1) a step of applying a colored paint to form a colored coating film;
(2) a step of applying a clear paint on the colored coating to form a clear coating;
(3) In a state where at least a protective sheet having a colorimetric area of the coating plate opened is present between the surface of the clear coating film that is not completely dried and the colorimeter, the clear coating is performed. A step of measuring the color from the surface of the film using a colorimeter,
A method for measuring the color of a painted plate, including:   The colorimetry method for a coated plate according to claim 1 or 2, further comprising a step of placing the clear coating film formed in the step (2) at a temperature of 15 to 80 ° C.   The colorimetric method for a coated plate according to any one of claims 1 to 3, further comprising a step of setting the solid content of the clear coating film to 40 to 100% by mass.   The colorimetric method for a coated plate according to any one of claims 1 to 4, wherein the clear paint is a urethane-curable paint containing a hydroxyl group-containing compound and a polyisocyanate compound.   The colorimetric method of a coated plate according to any one of claims 1 to 5, wherein the glass transition temperature of the clear coating film after drying is 50C or more.   The colorimetric method for a coated plate according to any one of claims 1 to 6, wherein a dry film thickness of the clear coating film is in a range of 10 to 50 µm.   The step of forming a colored coating comprises at least one of a step of forming a colored coating by spray coating, a step of setting the colored coating, and a step of preheating the colored coating. 8. The method for measuring a color of a coated plate according to any one of claims 1 to 7.   The colorimetry method for a coated plate according to any one of claims 1 to 8, wherein the thickness of the protective sheet is in a range of 10 to 200 µm.   The colorimetric method for a coated plate according to any one of claims 1 to 9, wherein an adhesive layer is provided on at least one surface of the protective sheet.   A toning method using the color measuring method for a coated plate according to any one of claims 1 to 10, wherein the colored paint is toned to a target color by mixing a material containing one or more pigments. A toning method comprising the step of measuring the color of a toning test coated plate, which is a toning paint, to which the toning paint is applied by the colorimetric method, and determining whether or not the toning compound of the toning paint is acceptable.