JP3064430B2 - Computer toning method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a computer-based method comprising measuring colorimetric data of a sample plate, measuring the gloss or gloss of the sample plate, and correcting the measured colorimetric data with the gloss. Regarding the color method.

[0002]

2. Description of the Related Art Conventional computer toning methods include, for example,
Do as follows.

First, color development data of a primary color paint, for example, K
Data (absorption coefficient data) and S data (scattering coefficient data) are collected as follows. Prepare the required number of primary color paints of the same paint type. A coated plate is made of a mixed paint of each primary color paint and a white paint whose coloring data is known. The coated plate is measured with a spectrophotometer to obtain spectral reflectance data. From this spectral reflectance data, K data and S data for each spectral wavelength of each primary color paint are calculated and determined by a known technique.

[0004] Alternatively, for example, a painted plate is made of a mixed paint of each primary color paint and an unknown white primary color paint, and from this painted plate, color development data relative to the white primary color paint is determined.

[0005] Then, computer toning calculation is performed as follows. The colorimetric data of the sample plate, for example, the spectral reflectance is measured using a spectrophotometer of the same type as the above-mentioned spectrophotometer. From the K data and S data of each primary color paint obtained as described above and the known Duncan's formula, the spectral reflectance distribution expected to show the coating color at an arbitrary primary color mixing ratio (formulation blend) is shown. Can be calculated. The primary color mixing ratio is determined by calculation using a numerical calculation method so that the spectral reflectance distribution approximates the measured spectral reflectance distribution of the sample plate.

[0006] The data of the painted plate and the sample plate can be measured as a spectral reflectance using a spectrophotometer as described above, and further, a colorimetric value (X,
Y, Z) and the like.

[0007] The conventional computer toning method as described above has the following problems. According to the study of the present inventor, when determining the coloring data of the primary color paint as described above, if the coated plate surface is not constant and the glossiness varies between the coated plates, a suitable computer toning is performed. If the gloss of the sample plate is different from the gloss of the coated plate used for determining the coloring data of the primary color paint, it is not possible to perform suitable computer toning.

[0008] This is because the measured color development data and the color measurement data differ depending on the surface condition of the coating film, that is, the glossiness, even if the coloring characteristics inside the coating film are the same. It is understood that accurate correction of toning cannot be performed without correcting.

[0009]

A problem to be solved is to provide a computer toning method capable of calculating a more accurate primary color mixing ratio.

Means for Solving the Problems The glossiness of a coated plate and the glossiness of a sample plate for collecting color development data of primary color paints are measured, and the colorimetric data of the sample plate is measured for the glossiness of the coated plate. And the glossiness of the sample plate, and computer toning calculation is performed based on the corrected colorimetric data of the sample plate.

[0011]

EXAMPLES A primary white paint and a primary black paint of a thermosetting melamine / alkyd paint were prepared. The white primary color paint and the black primary color paint were mixed at the ratio (% by weight) shown in Table 1 below to adjust the paint, and spray-coated so as to completely conceal the base of the coated plate. Drying was performed to prepare four coated plates.

Table 1 Formulation of primary color paint Paint Black 19.9.63 0.37 2 97.61 2.39 3 93.02 6.98 4 68.71 31.29 50.00 100.00 Next, the same A clear coating material A is prepared by preparing a clear coating material (transparent coating material) in which the color pigment is not dispersed and mixed as a coating material, and stepwise adding and mixing a matting agent in the ratio (% by weight) shown in Table 2 below. ~ D were prepared. As the matting agent, a matting agent having a refractive index close to that of the clear paint and thus reducing the glossiness without hindering the transparency of the clear coating film was selected.

Table 2 Formulation of clear paint Clear paint ABCD Clear paint amount 100.0 100.0 100.0 100.0 Matting agent 0.0 2.3 4.0 7.0 Clear as described above Paints A to D were prepared as described above so that the thickness of the dry paint was 10 μm.
Spray painted on the coated plate according to No. 5, sample coated plates 1A-1D, 2A-2D, as shown in Table 3 below,
3A-3D, 4A-4D and 5A-5D were made.

Table 3 Sample Coated Plates ABCD 11A 1B 1C 1D 22A 2B 2C 2D 3 3A 3B 3C 3D 4 4A 4B 4C 4D 5 5A 5B 5C 5D These sample coated plates 1A to 1D, 2A to 2D 3
D, 4A to 4D and 5A to 5D are considered to provide a series of five levels having the same coloring characteristics inside the coating film and the coating surface condition, that is, the glossiness is gradually different.

Strictly speaking, the difference in the addition concentration of the matting agent itself slightly changes the coloring properties of the clear coating film constituting the surface layer of the coating film. For this reason, when more strictness is required, samples 1 to 5 are directly used regardless of the clear paints A to D.
Sanding in a step-by-step manner or crimping on a mold with a stepped surface state before curing,
It is desirable to prepare a series in which the surface state of the samples 1 to 5, that is, the glossiness is gradually changed by a method such as curing.

Sample coated plates 1A to 1 prepared as described above
D, 2A-2D, 3A-3D, 4A-4D and 5A-5
D is a spectrophotometer Sigma SZ80 (manufactured by Nippon Denshoku Co., Ltd.) and 60 ° specular gloss meter (GM-2 manufactured by Murakami Color Research Laboratory Co., Ltd.)
6D), the spectral reflectance and 60 ° specular gloss G6
0 was measured. The measured values were as shown in Table 4 below. In Table 4, the upper row is 60 °
The specular gloss G60 is shown, the middle part shows the reflectance at a spectral wavelength of 560 nm, and the lower part shows the difference ΔR of the reflectance with respect to A of each series.

Table 4 Glossiness and Reflectivity of Material Coated Plate ABCD 190.1 69.6 39.3 7.5 76.05 75.07 74.16 74.70 0.0 0.98 1. 89 1.35 2 91.1 68.8 38.4 7.5 55.27 54.34 53.59 54.32 0.0 0.93 1.68 0.95 3 90.7 66.5 37. 8 7.2 39.06 38.20 37.53 38.25 0.0 0.86 1.53 0.81 4 87.5 57.7 34.0 8.9 15.56 15.23 15.21 16.03 0.0 0.33 0.35 -0.48 5 88.9 62.9 40.5 24.0 0.39 0.39 0.41 0.51 0.0 0.0 -0.0. 02-0.46 Two variations of 60 ° specular gloss G60 and reflectance as shown in Table 4 above. By plotting the functional relationship between reflectance ΔR it was shown in FIG. In FIG. 1, △ indicates that the reflectance is 80.
% Indicates about 1A to 1D, x indicates 2A to 2D whose reflectivity is about 60%, ○ indicates 3A to 3D whose reflectivity is about 40%, and ● indicates about 20% reflectivity. 4A to 4D, and □ indicates 5A to 4D whose reflectance is about 0%.
5D is shown.

Based on Table 4 and FIG. 1, 60 ° specular gloss G
The function of ΔR with the two variables of 60 and the reflectance R was determined as follows.

In the following formula, (1) is G60 ≦
A region 40 (FIG. 1), that is, 60 ° specular gloss G
60 ° specular gloss G60 in an area where 60 is 40 or less
(2) is a B region where G60> 40 (FIG. 2), that is, 60 ° specular gloss G60 is 40.
Shows the relationship between 60 ° specular gloss G60 and ΔR in the region exceeding.

ΔR = f (R, G60) where: ΔR = R (I), I = 400 to 700 nm (1) G60 ≦ 40 ΔR = a (R) * G60 + b (R) where a (R) = (0.017 * R-3.122) / 100 b (R) = (0.002 * R ＾ 2-0.491 * R + 11.999) / 100 (2) G60> 40 ΔR = c (R ) * G60 + d (R) where c (R) = (− 0.001 * R ＾ 2 + 0.609 * R + 0.383) / 1000 d (R) = (0.002 * R ＾ 2−0.635) * R-0.196) / 10 In general, in each series in which the color development characteristics in the coating film are considered to be substantially the same, four such as the spectrophotometer Sigma SZ80 are used.
In a colorimeter having an optical condition of 5 ° / 0 ° (illumination light angle / light receiving angle), the reflectance once measured decreases as the 60 ° specular gloss G60 decreases. It was noted that the rates tended to rise. Further, it was recognized that the degree of the decrease in the reflectance was more remarkable in a sample coated plate having a smaller series number, that is, a sample coated plate having a higher reflection.

The verification was performed as follows using the correction function f determined as described above.

A white primary color paint, a black primary color paint, a yellow primary color paint and a blue primary color paint are prepared with the above-mentioned paint types, and are mixed in proportions (% by weight) as shown in Table 5 below, and paint 6 is obtained. , 7 and 8 were prepared to prepare three coated plates each.

Table 5 Composition of primary color paints Paint White Black Yellow Blue 6 45.77 10.17 16.61 27.45 7 62.99 19.83 8.37 8.82 8 72.96 16.54 3.03 7.47 The primary color paints were mixed and the paints were adjusted as shown in Table 5 above, and three coated plates were prepared in the same manner as described above. The clear paints A, C, and D adjusted as shown in Table 2 above were applied to the thus-prepared coated plate, respectively, and the sample coated plate 6 was coated.
A, 6C and 6D, 7A, 7C and 7D, 8A, 8C and 8D were prepared, and these samples were coated using a 60 ° specular gloss meter (GM-26D, manufactured by Murakami Color Research Laboratory Co., Ltd.).
The 0 ° specular gloss G60 was measured. The measured values were as shown in Table 6 below.

Table 6 60 ° Specular Gloss G60 Paint ACD 6 89.1 31.6 9.1 7 90.4 33.1 9.3 8 91.5 32.5 8.9 Paints 6, 7 and 8, sample coating plates 6A, 7A and 8A prepared by applying clear coatings A, C and D
Spectral reflectance RA at 8 wavelengths from 0 to 680 nm
(Λ) is converted to a spectrophotometer Sigma SZ80 (Nippon Denshoku Co., Ltd.)
Was used for the measurement. The results were as shown in Tables 7, 8, and 9.

Further, using these values and the correction function f as described above, the specular glossiness is calculated as the expected reflectance of the GA (R * A ← RC) according to the following equation.
And (R * A ← RD) were calculated.

Then, the actually measured value RA and the expected reflectance value (R *
Difference between A ← RC) and (R * A ← RD), RA− (R *
A ← RC) and RA− (R * A ← RD) were obtained.

These values are shown in Tables 7 and 8 below.
And as shown in Table 9.

[0028]

[Table 7]

[0029]

[Table 8]

[0030]

[Table 9]

RA * (λ) = Ro (λ) −ΔRo (λ) + ΔRA
(Λ) ΔRo (λ) = f (Ro (λ), Go) ΔRA (λ) = f (Ro (λ), GA) As shown in Tables 7, 8, and 9, the difference RA−
The values of (R * A ← RC) and RA− (R * A ← RD) are both small. This indicates the degree of coincidence between the calculated value RA * (λ) and the measurement data RA (λ), and indicates the rationality of the correction function f. By determining the correction function f on the basis of the experimental data as described above, the spectral reflectance in a surface state where the sample exhibits an arbitrary specular gloss can be determined with high accuracy from the measured values of the specular gloss and the spectral reflectance. It was confirmed that the estimation was made.

Therefore, for example, the gloss GP of the coated plate when measuring the color development data of the primary color paint is measured, the colorimetric data of the sample plate and its gloss GS are measured, and the colorimetric data D1 of the sample plate are measured. Accordingly, the colorimetric data D2 when the sample plate has the glossiness GP, for example, can be calculated using the correction function f. By using the calculated measurement data D2, more accurate computer toning calculation can be performed.

Next, sample plates A, B and C were prepared as follows.
Was prepared, and computer toning as in the prior art and computer toning according to the present invention were performed, and the results of these tonings were compared.

Sample sheets A, B, and C were prepared using a thermosetting melamine-alkyd paint, and 6 sheets of these sample sheets were prepared.
The 0 ° specular gloss G60 and the spectral reflectance were measured. The results were as shown in Table 10 below.

[0035]

[Table 10]

White with a thermosetting melamine-adhesive paint,
Prepare 7 primary color paints of black, red, yellow, blue, green, orange,
A paint plate prepared by measuring and mixing each primary color paint and a predetermined primary color paint is used as a spectrophotometer Sigma SZ80 (Nippon Denshoku Co., Ltd.)
And K data (λ) and S data (λ) of each primary color paint were calculated and determined based on a known technique. The 60 ° specular gloss of the coated plate was almost the same in the range of 92 ± 3. When the gloss levels of these coated plates are significantly different, the gloss levels can be matched by applying a clear paint, sanding, or the like. Further, according to the description of the present specification, the measured reflectance of the coated plate of the primary color paint can be corrected to the reflectance at a predetermined glossiness.

The primary color paint formulation corresponding to the spectral reflectances in Table 10 was determined by computer toning calculation. The results were as shown in Table 11 below.

Table 11 Formulation of primary color paint C Sample plate White Black Red Yellow Blue Green Orange A 47.63 11.92 0.0 15.37 25.08 0.0 0.0 B 93.41 0.91 0. 0 5.64 0.0 0.05 0.0 C 18.03 1.70 19.15 0.0 0.0 0.0 61.12 Weighed and blended according to the formulation in Table 11, and gloss of sample plate In order to conform to the above, an appropriate amount of matting material was further added to prepare a coated plate, which was used as a test plate GT. And these test plates were measured. The results were as shown in Table 12 below. Table 12 shows the results obtained by the conventional method without correcting the glossiness.

[0039]

[Table 12]

Next, as shown in Table 10, 6
Using the 0 ° specular gloss G60 and the correction function f as described above, the reflectance of the sample plate as shown in Table 10 was calculated as the corrected reflectivity at the 60 ° specular gloss 92.
The calculation results are as shown in Table 13 below.

[0041]

[Table 13]

The corrected primary color paint composition corresponding to the corrected reflectance as described above was calculated by computer toning calculation. The calculated corrected primary color paint composition is as shown in Table 14 below.

Table 14 Formulation of primary color paint C 'Sample plate White Black Red Yellow Blue Green Orange A 45.77 10.17 0.0 16.61 27.45 0.0 0.0 B 93.98 0.770 0.0 5.20 0.0 0.05 0.0 C 18.33 1.66 18.69 0.0 0.0 0.0 61.32 The formulations as shown in Table 14 were weighed and toned. To match the gloss of the sample plate, an appropriate amount of matting material was added to prepare a coated plate, which was used as a test plate GT '. Then, the 60 ° specular gloss G60 and the spectral reflectance of these test plates were measured. The measurement results are as shown in Table 15 below.
Table 15 shows the results obtained by the method according to the present invention, in which the correction was made based on the glossiness.

[0044]

[Table 15]

By comparing the values in Tables 10, 12, and 15,
Difference Δ between reflectance R (λ) of sample plate and reflectances RT (λ) and RT ′ (λ) of test plates prepared by each method.
(Λ) and Δ ′ (λ) were determined. The results were as shown in Tables 16 and 17.

[0046]

[Table 16]

[0047]

[Table 17]

The differences shown in Table 17 are smaller than the differences shown in Table 16 for all three examples A, B, and C, and the toning accuracy is improved by correcting the measured reflectance with the correction function f. It is shown that.

Further, when the sample plate and the test plate were visually observed, sufficient color matching was confirmed in all three cases in the method in which the reflectance was corrected, and clear color mismatch was confirmed in the method in which the reflectance was not corrected. Was.

In the preferred embodiment of the present invention as described above, the colorimetric data of the sample plate is corrected based on the glossiness, and a known computer toning calculation is performed based on the corrected colorimetric data.

The gloss correction function can be obtained as described above. For this reason, it is possible to configure the computer so that the correction calculation of the glossiness by the correction function is also performed by the computer, and further, the glossiness and the colorimetric data of the sample plate, the glossiness of the painted plate, and the coloring of the primary color paint are provided to the computer. By inputting the data, the computer can be calculated in accordance with a conventional calculation procedure based on the known toning calculation and the correction function as described above.

[0052]

As described above, according to the present invention,
Measure the gloss of the painted board and the gloss of the sample board for collecting the color development data of the primary color paint, and measure the color measurement data of the sample board.
The glossiness of the painted plate and the glossiness of the sample plate are corrected, and a computer toning calculation is performed based on the corrected colorimetric data of the sample plate. For this reason, it is possible to calculate a more accurate primary color mixing ratio in computer toning.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a relationship between a 60 ° specular gloss G60 and a reflectance difference ΔR.

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Mori Takashi 3-12-1, Minamirokugo, Ota-ku, Tokyo Kansai Paint Co., Ltd. (56) References JP-A-61-23929 (JP, A) 3-85419 (JP, A) JP-A-59-216024 (JP, A) JP-A-61-19675 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01J 3/00 -3/52

Claims (2)

(57) [Claims] 1. A method for producing a coated plate using each of the primary color paints, measuring the glossiness of these coated plates, and measuring the color of these coated plates to obtain color development data for each of the primary color paints. Measuring the sample plate to obtain its glossiness and colorimetric data; correcting the colorimetric data of the sample plate according to the glossiness of the coated plate and the glossiness of the sample plate; According to the color data and the coloring data of the primary color paint,
A computer toning method comprising performing computer toning calculations. 2. A method of producing a coated plate using each of the primary color paints, measuring the glossiness of these coated plates, and measuring the color of the coated plates to obtain color development data of each of the primary color paints. Measuring the sample board to obtain its glossiness and colorimetric data, and calculating the computer toning based on the glossiness and colorimetric data of the sample board, the glossiness of the painted board, and the coloring data of the primary color paint. And a computer toning method.