JP7001322B2 - Clear paint composition for toning test coating board, and toning method using this - Google Patents

Description

The present invention relates to a clear coating composition suitable for a toning test coating plate produced in the course of toning work and a toning method using the same.

In the repair painting of automobile outer panels, after the damaged part is filled with putty or surfacer, the toning paint is widely painted around the damaged part. When painting with toning paint, it is important to match the color of the part to be painted with the surrounding color to create a natural appearance.

Therefore, it is necessary to adjust the color of the paint around the damaged part as the target color. The toning paint is a mixture of a plurality of primary color paints, colored pigment pastes, bright pigment pastes, coloring materials such as gloss adjusters, additives, etc. (sometimes referred to as primary colors) in various ratios. Usually, the paint is prepared by performing the color matching work at a paint shop, an automobile repair factory, a color matching factory, or the like.

In recent years, the number of automobiles with complicated paint colors has increased, and in the field of automobile repair painting, it has become common to use color sensors and computers for toning work.

In the computer toning method (computer color matching CCM), the characteristic values of each primary color are input to the computer in advance, while the car body to be repaired is measured with a color sensor and various data are collected to obtain the primary colors. This is a method of calculating the blending ratio with a computer and weighing and mixing the primary color paints based on the blending ratio obtained as a result to create a toning paint. The toning paint thus obtained is applied to a test substrate and cured and dried to prepare a toning test coating plate. If the toning test coating plate is not good, measure the color of the toning test coating plate with a color sensor, collect various data, calculate it with a computer to obtain the correction composition, create the toning test coating plate, color ratio, Repeat the work of determining pass / fail.

As described above, in order to efficiently obtain the desired toning paint in the computer toning method, it is important to accurately measure the target color and the toning test coating plate and acquire appropriate color data.

In order to accurately measure the toning test coating plate, especially the metallic color test coating plate, it is necessary not only to apply the toning paint but also to apply the clear paint on the toning coating film and dry it. Generally, at the repair painting site, a two-component urethane clear at the repair painting site is used as the clear paint for recoating. For this reason, it takes time to weigh and mix the two liquids (main agent and curing agent), and it takes time to paint and dry. Nevertheless, he spends a lot of time and effort on the clear paint painting process.

As a method of reducing the time required to create a toning test coating plate, Patent Document 1 describes in advance that the coating surface A is prepared with an organic solvent when comparing the metallic coating surface A after toning and the metallic coating surface B of the target color. It discloses a toning determination method characterized by keeping it moist. According to this method, the gloss of the metallic coated surface can be made to look like a clear paint is overcoated in a short time. However, with this method, depending on the target color, it may not be possible to obtain an accurate toning paint formulation.

Further, in Patent Document 2, a liquid that does not dissolve this coating film is applied on a touch-dried colored paint coating film, a colorless transparent solid thin film is placed on the liquid coating film, and the color is colored through the thin film. A method of performing color matching work by measuring the color of a paint film is described. However, when this method is used for a metallic color toning coating film, there is a problem that unevenness occurs in the metallic coating film due to the placement of a thin film.

Japanese Unexamined Patent Publication No. 9-178559 Japanese Unexamined Patent Publication No. 2001-336981

An object of the present invention is suitable for forming a clear coating film that can save time and labor required for producing a toning test coating plate and can accurately measure the color measurement data of the toning coating film located in the lower layer. It is an object of the present invention to propose a clear coating composition and a toning method using the clear coating composition.

As a result of diligent studies on the above-mentioned problems, the present inventors adjusted the ratio of the binder resin component and the volatile component in the composition as the clear paint composition used for the top coat of the toning test coating plate, and then gelled. When a paint that forms a coating film that does not have a fraction or is in a specific range is used, color measurement data that matches or approximates the target color can be obtained, and a highly accurate toning composition can be obtained. I found.

That is, the present invention
Item 1
The step of applying the toning paint to the test substrate, the binder resin component (A) and the organic solvent (B) are contained on the toning coating film obtained in the above step, and the organic solvent (B) is contained. The amount of the ester-based organic solvent occupies 70% by mass or more,
A step of coating a clear coating composition having a non-volatile content concentration of 10% or more and a gel content of the formed coating film of 10% or less, the toning coating film is passed through the clear coating film obtained in the above step. A toning method that includes the process of measuring color with a colorimeter.
Item 2
The color of the raw material for toning paint based on the process (1) and the color data acquired in step (1) of measuring the color of the object to be repaired as the target color with a colorimeter and acquiring the color data of the target color. A computer that registers the data and the color matching logic based on the color data calculates the blending ratio of the raw materials. The toning paint is created based on the blending ratio of the raw materials obtained in the steps (2) and (2). Item 1. The toning method according to Item 1.
Item 3
The process of measuring the color of the object to be repaired with a colorimeter and acquiring the color data of the target color (1),
Based on the color data acquired in step (1), the step (2) of calculating the blending ratio of raw materials by a computer in which the color data of the raw materials for toning paint and the color matching logic based on the color data are registered.
Step (3), in which the first toning paint is prepared based on the blending ratio of the raw materials obtained in the step (2),
Step (4), in which the first toning paint obtained in step (3) is applied to the test substrate to form a toning coating film.
The step (5), in which the clear coating composition according to Item 1 is applied onto the toning coating film obtained in the step (4).
Step (6), in which the toning coating film obtained in step (4) is color-measured with a colorimeter via the clear coating film obtained in step (5).
Including the step (7) of calculating the blending ratio for the toning paint for correction by a computer based on the color data acquired in the steps (1) and (6).
A step of creating a toning paint, a step of forming a toning coating, and a step of applying the clear coating composition according to Item 1 on the toning coating until the test coating plate obtained in the step (5) passes. A toning method that repeats the process of calculating the blending ratio for a toning paint for correction by a computer.
Item 4
Item 6. The color matching method according to any one of Items 1 to 3 , wherein the binder resin component (A) contained in the clear coating composition contains at least one resin selected from an acrylic resin and a cellulose derivative.
Item 5
Item 6. The color matching method according to any one of Items 1 to 4 , wherein the total amount of the first petroleums and the second petroleums in the organic solvent (B) of the clear coating composition is 90% by mass or more.
Item 6
Item 6. The color matching method according to any one of Items 1 to 5 , wherein the clear coating composition does not contain a curing agent.
Item 7
Item 6. The color matching method according to any one of Items 1 to 6 , wherein the clear coating composition is a one-component type.
Item 8
Item 6. The color matching method according to any one of Items 1 to 7 , wherein the clear paint composition is contained in an aerosol can.

Regarding.

By using the clear coating composition of the present invention as the top coat of the test coating plate for toning, highly accurate color data can be obtained even with a complicated coating color. As a result, a desired toning paint can be obtained. By using the clear paint composition of the present invention for the toning work, the man-hours for the toning work until the target color is reached can be reduced, and the time and labor required for the worker can be greatly reduced.

The clear paint composition of the present invention is used as a top coat of a test coating plate for toning, which is prepared on a trial basis in order to determine the pass / fail of blending of a toning paint that is a mixture of a plurality of primary color paints and is color-matched to a target color. It is a composition containing a binder resin component (A) and an organic solvent (B).

<Binder resin component (A)>
The binder resin component (A) can be used without particular limitation as long as it is a resin having a coating film forming ability that can be normally used in the paint field. The resin component (A) has a weight average molecular weight of 10,000 to 100,000, preferably 20,000 to 100,000, from the viewpoint of the appearance and dryness of the test coating plate for toning using a metallic color. It is preferable to include a resin within the range.

In the present specification, the weight average molecular weight is a value obtained by converting the weight average molecular weight measured by a gel permeation chromatograph (“HLC8120GPC” manufactured by Tosoh Corporation) based on the weight average molecular weight of polystyrene. The columns are "TSKgel G-4000H x L", "TSKgel G-3000H x L", "TSKgel G-2500H x".
Using four lines of "L" and "TSKgel G-2000H x L" (both manufactured by Tosoh Corporation, trade name), mobile phase; tetrahydrofuran, measurement temperature; 40 ° C., flow velocity; 1 cc / min, detector; It was done under the condition of RI.

Specific examples of the resin include an acrylic resin, a cellulose derivative, a polyester resin, an alkyd resin, an epoxy resin, a fluororesin, a vinyl chloride resin, and the like, or a mixed resin containing two or more of the above resins. Among them, at least one resin selected from acrylic resins and cellulose derivatives can be preferably used.

Examples of the acrylic resin include a (meth) acryloyl compound and, if necessary, a resin containing another polymerizable unsaturated compound as a copolymerization component.

Examples of the compound to be a copolymerization component include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, and iso-butyl. (Meta) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, dodecyl (meth) acrylate (Lauryl (meth) acrylate), tridecyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, cyclo Alkyl or cycloalkyl (meth) acrylates such as dodecyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, tricyclodecanyl (meth) acrylate; acrylic acid, methacrylic acid, crotonic acid, maleic acid, itacon. Carboxyl group-containing polymerizable unsaturated compounds such as acids and β-carboxyethyl acrylates; 2-acrylamide-2-methylpropanesulfonic acid, allylsulfonic acid, sodium styrenesulfonic acid salt, sulfoethylmethacrylate and sodium salts and ammonium salts thereof, etc. Sulphonic acid group-containing polymerizable unsaturated compound; 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, 2-acryloyloxypropyl acid phosphate, 2-methacryloyloxypropyl acid phosphate, etc. Acid group-containing polymerizable unsaturated compounds such as unsaturated compounds; carbons such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate. Hydroxylalkyl (meth) acrylates of 2-8; N-methylolacrylamide; Allyl alcohol; ε-caprolactone-modified acrylic compounds of hydroxyalkyl (meth) acrylates of 2-8 carbons; Diethylene glycol (meth) acrylates, triethylene Glycol (meth) acrylate, polyethylene glyco Hydroxyl group-containing polymerization of polyalkylene glycol (meth) acrylates such as le (meth) acrylates, dipropylene glycol (meth) acrylates, tripropylene glycol (meth) acrylates, polypropylene glycol (meth) acrylates, and polyethylene polypropylene glycol (meth) acrylates. Sexual unsaturated compound; aromatic ring-containing polymerizable unsaturated compound such as benzyl (meth) acrylate, styrene, α-methylstyrene, vinyltoluene; vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane , Gamma- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxysilane, a polymerizable unsaturated compound having an alkoxysilyl group; N-methoxymethyl (meth) acrylamide, N-butoxymethyl Alkoxyalkyl (meth) acrylates such as (meth) acrylamide, methoxyethyl (meth) acrylates, methoxypropyl (meth) acrylates, ethoxyethyl (meth) acrylates, ethoxypropyl (meth) acrylates, polyethylene glycol monomethoxy (meth) acrylates, etc. Polyalkylene glycol monoalkoxy (meth) acrylate and other alkoxy group-containing polymerizable unsaturated compounds; perfluorobutylethyl (meth) acrylate, perfluorooctylethyl (meth) acrylate and other perfluoroalkyl (meth) acrylates; fluoroolefin Polymerizable unsaturated compounds having a fluorinated alkyl group such as; polymerizable unsaturated compounds having a photopolymerizable functional group such as a maleimide group; N-vinylpyrrolidone, ethylene, butadiene, chloroprene, vinyl propionate, vinyl acetate and the like. Vinyl compounds; allyl (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, trimethyl propane Tri (meth) acrylate, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tetra (Meta) acrylate, glycerol di (meth) acrylate, 1 , 1,1-Trishydroxymethylethandi (meth) acrylate, 1,1,1-Trishydroxymethylethanthry (meth) acrylate, 1,1,1-Trishydroxymethylpropanetri (meth) acrylate, Triallyl isocia A polymerizable unsaturated compound having at least two polymerizable unsaturated groups in one molecule, such as nurate, diallyl terephthalate, and divinylbenzene; (meth) acrylonitrile, (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate. , N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide, nitrogen-containing polymerizable unsaturated compounds such as adducts of glycidyl (meth) acrylate and amines; glycidyl (meth) Acrylate, β-methylglycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 3,4-epoxycyclohexylethyl (meth) acrylate, 3,4-epoxycyclohexylpropyl (meth) acrylate, allylglycidyl ether Epoxy group-containing polymerizable unsaturated compounds such as 2-isosyanatoethyl (meth) acrylates, m-isopropenyl-α, α-dimethylbenzyl isocyanate and other isocyanato group-containing polymerizable unsaturated compounds; (Meta) acrylates with a polyoxyethylene chain; acrolein, diacetone acrylamide, diacetone methacrylate, acetoacetoxyethyl methacrylate, formyl styrene, vinyl alkyl ketones with 4-7 carbon atoms (eg, vinyl methyl ketones, etc.) Examples thereof include carbonyl group-containing polymerizable unsaturated compounds (vinyl ethyl ketone, vinyl butyl ketone) and the like. These polymerizable unsaturated compounds can be used alone or in combination of two or more.

The polymerization reaction of the above polymerizable unsaturated compounds can be carried out by a known method, for example, azo compounds such as azobisisobutyronitrile and azobis (2,4-valeronitrile); Oxide: Performed in an organic solvent using a radical polymerization catalyst such as a persulfate such as ammonium persulfate.

When the binder resin component (A) contains an acrylic resin, it is particularly suitable that the acrylic resin contains a hydroxyl group from the viewpoint of the pigment orientation of the metallic color toning test coating plate.

When the acrylic resin contains a hydroxyl group, the hydroxyl value of the acrylic resin is preferably in the range of 5 to 200 mgKOH / g, preferably 30 to 150 mgKOH / g.

The cellulose derivative is a compound containing cellulose as a constituent unit. For example, an esterified product of cellulose in which the hydroxyl group of cellulose is esterified with an acid such as fatty acid or nitrate, or a polymerizable unsaturated group is introduced into the esterified product of the cellulose. Examples thereof include a cellulose-modified copolymer obtained by reacting the resulting polymerizable unsaturated group-containing cellulose esterified product with another polymerizable unsaturated compound.

Examples of the esterified product of cellulose include nitrocellulose, cellulose acetate butyrate, cellulose acetate, cellulose acetate propionate and the like. Of these, cellulose acetate butyrate can be preferably used.

Cellulose acetate butyrate (hereinafter sometimes abbreviated as CAB) is obtained by further butyl esterifying a partially acetylated product of cellulose, and specifically, for example, specifically, for example, "CAB-381-". 0.5 ”,“ CAB-381-0.1 ”,“ CAB-381-2.0 ”,“ CAB-381-20 ”,“ CAB-551-0.2 ”,“ CAB-551-0. 01 ”,“ CAB-553-0.4 ”,“ CAB-531-1 ”,“ CAB-500-5 ”,“ CAB-321-0.1 ”,“ Solus2100 ”,“ Solus2300 ”(above, USA) Commercial products such as (trade name) manufactured by Eastman Chemical Company can be exemplified, and these can be used alone or in combination of two or more.

When the binder resin component (A) contains both the acrylic resin and the cellulose derivative, the usage ratio of both is 5 to 95 parts by mass, particularly 50, based on the total mass of 100 parts by mass of the acrylic resin and the cellulose derivative. It is preferable that the amount exceeds 70 parts by mass.

<Organic solvent (B)>
As the organic solvent (B) used in the clear paint composition of the present invention, a normal paint solvent can be used, and specifically, a normal paint solvent can be used.
Esters such as ethyl acetate, butyl acetate, isobutyl acetate, diethylhexyl acetate, cyclohexyl acetate, 3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate Organic solvent;
Ketone-based organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl cyclohexanone, ethyl amyl ketone, diisobuicyl ketone, methyl hexyl ketone, and isophorone;
n-butane, n-hexane, n-heptane, n-pentane, n-octane, n-nonan, n-decane, n-undecane, n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n- Linear alkanes such as hexadecane and n-heptane;
2-methylbutane, 2,2-dimethylpropane, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2-methylhexane, 3-methylhexane, 2,3-dimethyl Pentan, 2,4-dimethylpentane, 2,2,3-trimethylpentane, 2,2,4-trimethylpentane, 3,4-diethylhexane, 2,6-dimethyloctane, 3,3-dimethyloctane, 3, 5-dimethyloctane, 4,4-dimethyloctane, 3-ethyl-3-methylheptane, 2-methylnonane, 3-methylnonane, 4-methylnonane, 5-methylnonane, 2-methylundecane, 3-methylundecane, 2,2 , 4, 6, 6-Branched alkanes such as pentamethylheptan;
Cyclopentane, t-decalin, cyclohexane, methylcyclohexane, ethylcyclohexane, 1,2-dimethylcyclohexane, 1,3-dimethylcyclohexane, 1,4-dimethylcyclohexane, propylcyclohexane, isopropylcyclohexane, 1,2-methylethylcyclohexane, Fat group such as cyclic alkanes such as 1,3-methylethylcyclohexane, 1,4-methylethylcyclohexane, 1,2,3-trimethylcyclohexane, 1,2,4-trimethylcyclohexane and 1,3,5-trimethylcyclohexane. Cyclohexane-based organic solvent;
Aromatic hydrocarbon-based organic solvents such as toluene and xylene;
Dioxane, tetrahydrofuran, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono n-propyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono n-butyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monotert-butyl ether, diethylene glycol Monomethyl ether, Diethylene glycol monoethyl ether, Diethylene glycol mono n-propyl ether, Diethylene glycol monoisopropyl ether, Diethylene glycol mono n-butyl ether, Diethylene glycol monoisobutyl ether, Diethylene glycol monotert-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol Ether-based organic solvents such as mono-n-propyl ether, propylene glycol monoisopropyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol monoisopropyl ether, methanol, isopropanol , Tert-butanol, secondary butanol, isobutanol, n-butanol, 2-ethylhexanol, n-octanol, benzyl alcohol and other alcohol-based organic solvents can be mentioned.

In the present invention, the content of the ester-based organic solvent in the organic solvent (B) is 70% or more, particularly from the viewpoint of the finishability of the test coating plate for toning, particularly the orientation of the bright pigment. It is preferably 80% or more.

Further, from the viewpoint of the dryness of the test coating plate for toning, it is suitable that the total amount of the first petroleum and the second petroleum in the organic solvent (B) is 90% by mass or more, particularly the first. It is even more preferable that the amount of the first petroleum in the total amount of 100 parts by mass of the petroleum and the second petroleum is in the range of 10 to 95 parts by mass and 30 to 80 parts by mass.

The first petroleum is an organic solvent belonging to the first petroleum of the fourth category specified in the Fire Service Act, and is an organic solvent having a flash point of less than 21 ° C at 1 atm, and the second petroleum is ignited. A point is an organic solvent having a temperature of 21 ° C or higher and lower than 70 ° C.

The organic solvent (B) can be blended as a polymerization solvent and a dilution solvent in the binder resin (A), or for dilution in the production of a clear coating composition.

<Clear paint composition>
The clear coating composition of the present invention has a non-volatile content concentration of 10% by mass or more, preferably 10 to 70% by mass, particularly preferably 15 to 35% by mass.

In the present invention, when the non-volatile content concentration of the clear coating composition is 10% by mass or more, the color tone, gloss, and pigment orientation of the metallic color toning test coating plate, which is considered to be particularly difficult to tones, are good. , It is possible to perform color measurement accurately.

In the present specification, the non-volatile content concentration is the mass ratio (%) of the non-volatile substance to the total amount of the clear coating composition. Examples of the non-volatile substance include a resin binder (A) and an additive to be blended as needed. The non-volatile content concentration can be measured, for example, by allowing 3 grams of the sample to stand in a dryer at 105 ° C. for 3 hours to dry, and then dividing the mass of the dried sample by the mass of the sample before drying. can.

The amount of the binder resin component (A) contained in the non-volatile substance is preferably 70% by mass or more, and more preferably 80 to 95% by mass.

As the additive, a plasticizer, a surface conditioner, a rheology control agent, a surface conditioner and the like can be used.

Of these, the plasticizer has good compatibility with the binder resin component (A), and even when coated on a metallic color toning coating, a toning test coating plate having excellent pigment orientation is available. A liquid ester-based plasticizer is preferable because it can be obtained. Examples of the liquid ester-based plasticizer include resins that are liquid at 25 ° C. and have a weight average molecular weight in the range of 500 or more and less than 10,000, preferably in the range of 800 to 5,000. can.

Specific examples of the liquid ester-based plasticizer include polyester-based plasticizers, acrylic-based plasticizers, and the like, which may be used alone or in combination.

When a liquid ester-based plasticizer is used, it is preferable that the amount is 25 parts by mass or less, preferably 5 to 20 parts by mass, based on 100 parts by mass of the binder resin component (A).

Examples of the surface conditioner include a silicone-based surface conditioner, a fluorine-based surface conditioner, an acrylic surface conditioner, and the like, which may be used alone or in combination. The amount of the surface conditioner is preferably 3.0 parts by mass or less, preferably 0.05 to 1.5 parts by mass, based on 100 parts by mass of the binder resin component (A).

Further, in the present invention, the coating film formed from the clear coating composition does not have a gel fraction, or has a gel fraction of 10% or less. By using a clear paint composition as a top coat that forms a clear coating film with a gel content of 10% or less, even a color that is difficult to color, such as a metallic color, can be finished. It is possible to easily create an excellent test coating plate for toning and measure the color in a short time, which has the effect of reducing the total time required for the toning process.

The gel fraction generally represents the curability of the coating film, but in the present specification, it means the solvent extraction residue and is measured as follows.

The clear paint composition is coated on a polypropylene plate using an applicator so that the dry film thickness is 30 μm, dried at 60 ° C. for 5 minutes, the coating film is peeled off from the polypropylene plate, and the mass is put into a wire mesh. Measure. The wire mesh containing the coating film is left in an acetone solvent for 1 day, and then vibrated with an ultrasonic device for about 1 hour to dissolve it.
Then, the wire mesh containing the residual coating film is taken out, dried at 105 ° C. × 1 hour, and then the mass is measured and calculated by the following formula.
Gel fraction (%) = mass of residual coated wire mesh x 100 / mass of coated wire mesh In the present invention, in order to keep the gel fraction within the above range, a curing agent can be added to the clear coating composition. It is necessary to include as little as possible, and preferably not. In particular, when the clear paint composition does not contain a curing agent, the paint form of the clear paint composition of the present invention can be a one-component type, in addition to shortening the time for preparing a test coating plate for toning and measuring color. Therefore, it is possible to save the trouble of measuring and mixing the main agent and the curing agent.

The curing agent in the present invention is a compound having at least two functional groups in the molecule capable of reacting with the functional group contained in the binder resin component (A), and specific examples thereof include polyisocyanate compounds and melamine compounds. Compounds can be mentioned.

As the container for accommodating the clear paint composition of the present invention, conventionally known ones can be used without any particular restrictions on the material, shape, etc. It can be done easily and is convenient.

<Color matching method>
In the method of the present invention, a step of applying a toning paint to a test substrate, a step of applying the clear paint composition on the toning coating film obtained in the above step, and the toning coating film are applied. It is a toning method including a step of measuring a color with a colorimeter through a clear coating film obtained in the step.

<Test base material>
As the test base material used in the method of the present invention, the substrate can be used without particular limitation as long as it is an object to be coated that can be used for producing a test coating plate for toning, and a metal plate, paper, a plastic film, or the like can be used. Can be used.

As for the size of the test coating plate for toning, the length of one side is generally about 5 to 20 cm.

<Toning paint>
The toning paint in the present invention is a paint containing at least one of a coloring pigment and a bright pigment (aluminum powder, bright mica powder, bright graphite, gold powder, copper powder, etc.), and is a plurality of primary color paints. A paint that is a mixture of raw materials including, and is color-matched to the target color. Examples of the raw material of the toning paint include a coloring pigment paste, a bright pigment paste, a gloss adjuster, an additive, and the like, in addition to the primary color paint.

The type and ratio of the primary color paint that is the compounding composition of the toning paint can be obtained by a known toning method, for example, an eye measurement toning method, a measurement toning method, or a computer toning method, but the target color is metallic. For complex colors such as paint and pearl luster, it is desirable to use the computer toning method.

<Creation of test coating board for toning>
In the present invention, the toning paint is applied to the test substrate so as to have a film thickness equal to or greater than the concealing film thickness.
After the toning paint is applied, it may be left at room temperature, but in some cases, it may be forcibly dried by applying hot air. Then, the clear coating composition of the present invention is coated on the obtained toning coating film. The dry film thickness of the clear paint composition is preferably about 10 to 80 μm, particularly about 20 to 60 μm, and the drying condition of the coating film, that is, the condition for volatilizing the solvent contained in the coating film is the ambient temperature. Is preferably 20 to 80 ° C. for 2 to 5 minutes. In this way, a test coating plate for toning is completed by applying a clear coating film on the toning coating film.

<Color measurement method of test coating plate for toning>
Next, in order to obtain the color data of the toning coating film, the toning coating film is measured with a colorimeter from the clear coating film side, that is, via the clear coating film.

As a colorimeter, if it is a measuring instrument that can measure the color of metallic paint or pearl color paint and acquire color data, it is particularly limited to the measurement principle, the calculation method from the measured value to the color data, etc. However, conventionally known ones can be used. In particular, it is preferable to have an irradiation light source that irradiates the surface of the object to be colored, and examples thereof include a single-angle colorimeter, a multi-angle colorimeter, and a micro-brightness measuring instrument.

<Repair target>
When the object to be repaired is the target color, the color data of the target color can be acquired by measuring the color of the object to be repaired with a colorimeter. The object to be repaired may be any one provided with a coating film made of paint, and specific examples thereof include vehicles such as automobiles, trucks, motorcycles, trains, and monorails, and industrial products. The coating film may be a single layer or a multi-layer, but in particular, it is a multi-layer coating film in which a clear coating film is provided on a coating film containing a bright pigment such as a metallic color or a pearly luster color. In some cases, the effect of the present invention can be maximized.

By inputting the color data obtained by measuring the color of the object to be repaired with a colorimeter to the computer in which the color data of the raw material for toning paint and the color matching logic based on the color data are registered, the color data is input. Acquire the mixing ratio of raw materials such as primary color paint.
Based on the blending ratio thus obtained, it is possible to prepare a first toning paint having a target color as the object to be repaired.

<Correction of blending ratio of toning paint>
If the first toning paint obtained by measuring the color of the object to be repaired and the toning test coating plate prepared using the clear paint composition of the present invention fail, the first toning paint is blended. Fine adjustment of the ratio is necessary.

The pass / fail judgment may be made by comparing the object to be repaired with the toning test coating plate with the human eye, or both are measured with a device such as a colorimeter and judged by the difference in the measurement results. Alternatively, the judgment by the human eye and the measurement by the device may be combined.

The compounding ratio for the second toning paint to be prepared for the second correction is prepared by using the color data of the object to be repaired as the target color, the first toning paint and the clear paint composition of the present invention. It can be obtained by inputting the color data obtained by measuring the color of the test coating plate for toning and calculating it.

In the present invention, when the test coating plate for toning prepared from the second time onward fails, the test coating plate passes by the same procedure as the method for obtaining the compounding ratio for the second toning paint. Create a toning paint for correction, create a test coating plate for toning, measure the color, and repeat the compounding ratio calculation.

The test coating plate for toning provided with the coating film using the clear coating composition of the present invention can be produced in a short time, and the color of the toning coating film can be accurately measured, up to the target color. The number of tonings can be reduced. Further, the clear paint composition of the present invention is used exclusively for the test coating plate for toning, but after the toning paint is applied and set, the clear coating composition is different from that of the present invention and the gel content exceeds 10%. It is possible to show good color matching with the coating color of the multi-layer coating film obtained by painting and drying the coating composition. Therefore, the painter can use the clear paint composition of the present invention separately when preparing the toning paint and the clear paint composition different from the present invention for the top coat of the actual painting, thereby resulting in the labor required for painting. Can be significantly reduced.

<Manufacturing of clear paint composition>
Examples 1 to 3 and Comparative Examples 1 to 3
Clear paint compositions (A-1) to (A-6) were prepared with the compounding compositions shown in Table 1 below. In Table 1, the notation of the binder resin component is a non-volatile component display.

<Evaluation test of clear paint composition>
(*) Gel fraction: Measured by the method described in the specification.
(*) Drying time: The clear paint compositions (A-1) to (A-6) are spray-coated on the steel sheet so that the dry film thickness is 30 μm, allowed to stand in an atmosphere of 60 ° C., and touched with a finger. The time until the coating film did not stick to the finger (finger corrosion drying time) was measured. The shorter the time, the better.
<Evaluation of toning workability using each clear paint composition>
In the following procedure, the clear paint compositions of Examples 1 to 3 and Comparative Examples 1 to 3 are used as the top coat of the test coating plate for toning, and the car body color of silver metallic color (referred to as car body parts (A)) is obtained. The targeted computer toning method was performed twice.
Each clear paint composition was used based on the dryness of each clear paint composition as a toning clear and the result of visual evaluation of the toning test coating plate 2 obtained by the second computer toning method. The toning workability was evaluated.

<Raw materials and computer color matching system used>
The primary color of "Retan PG Hybrid Eco" manufactured by Kansai Paint Co., Ltd. was used as the raw material for the toning paint.

The measurement of the target vehicle body parts (A), the test coating plates 1 and 2 for toning obtained by the first and second computer toning, is the multi-angle colorimeter "AI color sensor" manufactured by Kansai Paint Co., Ltd. ], The angle formed by the mirror reflection axis and the light receiving axis was measured under three angle conditions of 25 degrees, 45 degrees, and 75 degrees. The color measurement values are automatically imported into "AI Color Navi" manufactured by Kansai Paint Co., Ltd., and an approximate color search is performed from the database containing the paint color formulations and color measurement values created in the past. .. In other words, color matching was performed by operating a color matching calculation logic using a database in which the color characteristics of a plurality of primary color paints installed in "AI Color Navi" manufactured by Kansai Paint Co., Ltd. are registered.

Example 4
First, the target vehicle body part (A) was color-measured using an "AI color sensor" under three angle conditions of 25 °, 45 ° and 75 °. The results are shown in Table 1 below.

Next, using the "AI Color Navi" manufactured by Kansai Paint Co., Ltd., the colorimetric values in Table 2 automatically captured from the multi-angle colorimeter "AI Color Sensor" manufactured by Kansai Paint Co., Ltd. are used. The approximate formulation was searched, and the color matching calculation logic was activated to obtain the first toning candidate formulation as shown in Table 3.

The silver metallic paint (1) shown in Table 3 was spray-coated on a substrate (tin plate) having a size of 10 cm × 10 cm so that the dry film thickness was about 20 μm. After leaving it at 20 ° C. for 5 minutes to dry it to the touch, the clear paint composition (A-1) of Example 1 was sprayed so as to have a dry film thickness of 30 μm, and a test coating plate and a colorimeter were used. The first toning test coating plate was obtained by drying at 60 ° C. until it was finger-corrosion-dried so that it could be contacted.
For the above 1st toning test coating board, color measurement was performed under 3 angle conditions of 25 °, 45 ° and 75 ° using the multi-angle colorimeter "AI Color System" manufactured by Kansai Paint Co., Ltd. went. The results are shown in Table 4 below.

Based on the color measurement values in Table 4, the color matching calculation logic was operated again using "AI Color Navi" manufactured by Kansai Paint Co., Ltd., and the second toning candidate formulation was obtained. Although the second toning composition table is omitted, it is a modified composition of the first toning composition table.

Next, the silver metallic paint (2) prepared based on the second toning candidate formulation is spray-coated on a substrate (tin plate) having a size of 10 cm × 10 cm so that the dry film thickness is about 20 μm. Was done. After leaving it at 20 ° C. for 5 minutes to dry it to the touch, the clear paint composition (A-1) of Example 1 is sprayed to have a dry film thickness of 30 μm, and is finger-corrosion-dried at 60 ° C. It was dried until the second toning test coating plate was obtained.
For the above-mentioned 2nd color matching test coating plate, color measurement was performed under 3 angle conditions of 25 °, 45 ° and 75 ° using the multi-angle colorimeter "AI Color Sensor" manufactured by Kansai Paint Co., Ltd. rice field. The results are shown in Table 5 below.

Examples 5 to 6 and Comparative Examples 4 to 6
The first step targeting the vehicle body part (A) was performed in the same procedure as in Example 4 above except that the clear paint compositions (A-2) to (A-6) were used as the top coat of the toning test coating plate. The toning candidate formulation and the second toning candidate formulation were obtained, and the first toning test coating plate and the second toning test coating plate were prepared.

<Evaluation test>
(*) Dryness The dryness of the clear paint composition used for the test coating plate for toning was evaluated according to the following criteria.
◎: Clear paint The color can be measured with a colorimeter immediately after painting, and the drying property is very good.
◯: After applying the clear paint, it takes some time before the color can be measured with a colorimeter, and the drying property is good.
Δ: It takes a long time to measure the color with a colorimeter after applying the clear paint, so the drying property is slightly poor.
×: After applying the clear paint, it takes an extremely long time to measure the color with a colorimeter, so the drying property is poor.
(*) Visual evaluation The second toning test The coated plate was compared close to the vehicle body part (A), which is the target color, and the visual evaluation was performed according to the following criteria.
(*) Color tone ◎: The color tone matches well,
○: There is a slight difference in color tone, but it is at a practical level.
Δ: A clear difference in color tone is observed.
X: The difference in color tone is extremely noticeable.
(*) Gloss ◎: Gloss matches well,
○: There is a slight difference in gloss, but it is at a practical level.
Δ: A clear difference in gloss is observed.
X: The difference in gloss is extremely noticeable.
(*) Glitter pigment orientation ⊚: Glitter pigment orientation is well matched,
◯: There is a slight difference in the orientation of the bright pigment, but it is at a practical level.
Δ: A clear difference is observed in the orientation of the bright pigment.
X: The difference in the orientation of the bright pigment is extremely noticeable.

Claims (8)

The step of applying the toning paint to the test substrate, the binder resin component (A) and the organic solvent (B) are contained on the toning coating film obtained in the above step, and the organic solvent (B) is contained. The amount of the ester-based organic solvent occupies 70% by mass or more,
A step of coating a clear coating composition having a non-volatile content concentration of 10% or more and a gel content of the formed coating film of 10% or less, the toning coating film is passed through the clear coating film obtained in the above step. A toning method that includes the process of measuring color with a colorimeter. The color of the raw material for toning paint based on the process (1) and the color data acquired in step (1) of measuring the color of the object to be repaired as the target color with a colorimeter and acquiring the color data of the target color. A computer that registers the data and the color matching logic based on the color data calculates the blending ratio of the raw materials. The toning paint is created based on the blending ratio of the raw materials obtained in the steps (2) and (2). The color matching method according to claim 1 . The process of measuring the color of the object to be repaired with a colorimeter and acquiring the color data of the target color (1),
Based on the color data acquired in step (1), the step (2) of calculating the blending ratio of raw materials by a computer in which the color data of the raw materials for toning paint and the color matching logic based on the color data are registered.
Step (3), in which the first toning paint is prepared based on the blending ratio of the raw materials obtained in the step (2),
Step (4), in which the first toning paint obtained in step (3) is applied to the test substrate to form a toning coating film.
The step (5) of coating the clear coating composition according to claim 1 on the toning coating film obtained in the step (4).
Step (6), in which the toning coating film obtained in step (4) is color-measured with a colorimeter via the clear coating film obtained in step (5).
Including the step (7) of calculating the blending ratio for the toning paint for correction by a computer based on the color data acquired in the steps (1) and (6).
A step of creating a toning paint, a step of forming a toning coating, and a step of applying the clear coating composition according to claim 1 on the toning coating until the test coating plate obtained in the step (5) passes. , A toning method that repeats the process of calculating the blending ratio for a toning paint for correction by a computer. The color matching method according to any one of claims 1 to 3 , wherein the binder resin component (A) contained in the clear coating composition contains at least one resin selected from an acrylic resin and a cellulose derivative. The color matching method according to any one of claims 1 to 4 , wherein the total amount of the first petroleums and the second petroleums in the organic solvent (B) of the clear coating composition is 90% by mass or more. The toning method according to any one of claims 1 to 5 , wherein the clear coating composition does not contain a curing agent. The color matching method according to any one of claims 1 to 6 , wherein the clear coating composition is a one-component type. The color matching method according to any one of claims 1 to 7 , wherein the clear paint composition is contained in an aerosol can .