JPH0358053B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for predicting dye staining results. When a standard dye and a sample dye are dyed simultaneously, differences in shading appear in the dyed product depending on the ratio of the pigment components contained in each dye. The color characteristics of dyes are evaluated based on the color difference that occurs when the dye is dyed by correcting the color difference caused by this difference in shade and adjusting the color depth to be equal. Furthermore, this color difference can be divided into two types: a so-called hue difference, such as a reddish tendency or a bluish tendency, and a so-called sharpness difference, which relates to the vividness caused by the purity of the color. Normally, when a dyeing engineer evaluates the color of a dye by visual judgment, in addition to the hue difference and sharpness difference mentioned above, the amount of dye used when dyeing to obtain the same color strength, that is, the dyeing density. This is done using three values of dyeing power, which are percentages of the ratio of Currently, when testing the color characteristics of dyes, standard dyes and sample dyes are subjected to the so-called dyeing test procedure of preparing dye solution, dyeing, washing, and drying, and then comparing the dyed products obtained with standard dyed products. A method of evaluating color characteristics has been carried out. This method requires a great deal of time and effort, and there is an extremely high demand for a method that is economical, fast, and allows easy prediction of dyeing results. Therefore, the present inventors have diligently studied methods for predicting staining results in an economical, fast, and easy manner using a large amount of experimental data. As a result,
We have discovered a method that is economical, fast, and easy to predict staining results with high accuracy by completely omitting the staining operation. That is, in testing the color characteristics of dyes and measuring the color difference of a sample dye with respect to a standard dye, the present invention uses a solution of a representative sample of the same dye as the standard dye. Prepare each, measure the absorbance light curve, calculate the concentration tristimulus values QX, QY, QZ using absorbance instead of transmittance according to the usual tristimulus value calculation method, and then calculate the complementary color chromaticity coordinate xQ. , yQ, and the color density difference. In addition, we have previously selected one dye arbitrarily from among the dyes of the same item, measured its transmittance curve, obtained the tristimulus values X, Y, and Z from this, and then determined the appropriate isochromic color system. Convert to system. In this color system, the four sets of tristimulus values given by the chromaticity points are obtained when the hue difference, saturation difference, or sharpness difference is changed by a unit amount independently, and the transmittance curve corresponding to these values is mixed. This is determined by calculation using a calculation method, these are converted into an absorbance light curve, and the complementary color chromaticity coordinates of each chromaticity point are determined. From the coordinate difference between this and the complementary chromaticity coordinates of the dye arbitrarily selected above, the relationship between the hue difference and chroma difference or the sharpness difference and the complementary chromaticity coordinate difference in the isochromatic color system is clarified. put. Using this relationship, the hue difference and sharpness difference are determined from the liquid color difference of the representative sample of the same item of dye with respect to the dye having the above coordinates, and these are used as the dye liquid color difference. The hue difference from the dyeing color difference of the representative sample of the same item of dye with respect to the standard dye of the dyed products obtained by dyeing using the above-mentioned representative sample of the same item of dye as the standard dye. The difference in chroma or sharpness is determined and used as the difference in dye color. By statistical method, the color difference of dye liquid color and
Find the relationship between dye staining color difference. The dye solution color difference is determined as a hue difference and a sharpness difference in the same manner as in the above-mentioned method of measuring the liquid color difference of the sample dye of the same item with respect to the standard dye. From the dye liquid color difference of the sample dye of the same item with respect to the standard dye described above, using the relationship between the dye liquid color difference of and the dye dyeing color difference obtained in , A dye color difference measuring method is characterized in that the dye dyeing color difference of the sample dye is predicted. The method of the present invention is based on the new finding that there is a very good correlation between the color properties of a solution of a dye at an appropriate concentration and the color properties of the dyed result. That is, the absorbance of the dye solution is measured, the color density stimulus value is determined from this, the complementary color chromaticity coordinates are determined from this, the color difference with respect to the standard dye is determined, and the color difference is calculated separately from the previously determined dye color difference. This is a method of predicting the dyeing color difference from the liquid color difference using the relationship with the liquid color difference. Therefore, according to this method, the dyeing color difference is estimated from the solution color difference without performing a complicated dyeing test. Therefore, according to the present invention, the following excellent effects can be obtained. (a) By omitting various operations related to dyeing, significant test speed-up, process savings, labor savings, and energy savings can be achieved. (b) Current color difference evaluation methods for dyed products are subject to differences in dyeing results due to differences in the type and shape of the dyed product, differences in dyeing methods and dyeing machines, and visual perception judgments that tend to show individual differences among the judges. There are many factors that can cause poor accuracy, but the new color difference measurement method removes these factors and significantly improves accuracy. (c) Since the color difference of dyes can be obtained accurately and quickly, it can be widely used for process control of dye manufacturing, and significant economic effects such as a reduction in defective products and shortening of waiting time can be obtained. (d) The technology of the present invention can be widely used in the research and development stage of new dyes, and research can be promoted. (e) Able to quickly respond to hue change requests from dye users. Next, a typical method of the present invention will be explained in detail with reference to the drawings. The liquid color difference between a standard dye and representative samples (preferably several types) of the same dye is determined in exactly the same manner as described below. Spectrophotometric analysis of standard dyes and sample dyes is used to measure the absorbance curve in the visible spectrum wavelength range. Figure 1 is an example of this for a red dye, with 1
is the standard dye and 2 is the absorbance curve of the sample dye. Using these absorbances, the concentration tristimulus value QX,
Calculate QY and QZ using the following general formula (1). QX=∫Pλ
or those specified in Table 1 of JISZ8701 (display method of colors in the X, Y, Z system in a 2° visual field). May be used. Pλ is the standard spectral distribution of light, and the standard light corresponding to the light source that is often used for color evaluation of dyes is used. _D65 is usually used. Further, λ indicates the wavelength. dλ is the spectral wavelength interval when performing integral calculations, and is usually 10 or 20 nm. Next, the complementary color chromaticity coordinates xQ, yQ and color density value
SQ etc. are determined using the following equation (2). SQ=QX+QY+QZ xQ=QX/SQ yQ=QY/SQ (2) Using these results to create a complementary chromaticity diagram, we get
It will look like Figure 2. Here, the reason why complementary color chromaticity coordinates are particularly used is as follows. (a) The chromaticity point remains constant regardless of the solution concentration. (b) Color mixture calculations on the chromaticity diagram become additive, making it easier to understand trends in color differences. Further, after converting the absorbance curve of, for example, a standard dye in the same item into a transmittance curve using the following equation (3), the tristimulus values X, Y, and Z are determined using equation (4). Tλ=1/EXP(Dλ/0.4343) (3) Using equation (5), it is converted to an isometric color system, for example, the CIE1976 (L ^* a ^* b ^* ) color system recommended by CIE. L ^* = 116 (Y/Yo) ^1/3 -16 a ^* = 500 [X/Xo) ^1/3 - (Y/Yo) ^1/3 ] b ^* = 200 [(Y/Yo) ^1/3 - (Z/Zo) ^1/3 ] (5) Here, in the case of standard light D ₆₅ 10° field of view, X _p = 94.811 Y _p = 100.0 Z _p 107.334. In the a ^* b ^* chromaticity coordinates of this color system, the chromaticity point a ^* that gives the hue difference and saturation difference or sharpness difference
Chromaticity points [a ^* (1), b ^* (1)] to [a ^* (4), ^{b * (} 4)] (third Figure) gives four sets of tristimulus values [X(1), Y(1), Z(1)] ~
[X(4), Y(4), Z(4)] is obtained by inverse transformation of equation (5), and the spectral transmittance curve gives the respective tristimulus values.
Tλ is determined using computer color matching calculation for transmitted color (Figs. 4 to 7), and these are converted to an absorbance curve using Equation (8), and Equation (1):
Obtain the complementary chromaticity coordinates of each chromaticity point using (2). Complementary chromaticity coordinates given by this and the standard dye above
xQ(0), yQ(0) and the complementary chromaticity coordinates of each of the four chromaticity points obtained above [xQ(1), yQ(1)] ~
Find the relationship and relational expression of the difference between [xQ(4), yQ(4)] (Figure 8). Using these relationships and relational expressions shown in Figure 8, first, from the complementary chromaticity coordinates of the sample dye, a straight line passing through chromaticity points 1, 0, and 2 (hereinafter referred to as the equal visibility line) is drawn.
A parallel line is drawn, and the coordinates of the intersection A with a straight line passing through chromaticity points 3, 0, and 4 (hereinafter referred to as the equal hue line) are determined. Similarly, from the complementary chromaticity coordinates of the sample dye,
A parallel line is drawn to the equal hue line, and the coordinates of the intersection point B with the sharpness line are determined. Next, using the coordinates of these intersection points A and B, the liquid color difference is determined by the following equation (6). Liquid color hue difference = Length of straight line connecting chromaticity points 0 and B / Length of straight line connecting chromaticity points 0 and 2 Liquid color sharpness difference =
Length of the straight line connecting chromaticity points 0 and A/Length of the straight line connecting chromaticity points 0 and 3 In addition, using a conventionally known method, each dye is The hue difference, saturation difference, or sharpness difference is determined from the dyeing color difference of a representative sample of the same item of dye with respect to the standard dye of the dyed product obtained by dyeing, and these are used as the dye dyeing color difference. Next, the relationship between the dyeing color difference and the liquid color difference is determined by a statistical method, for example, by a regression line. Using the relationship, the color difference of the dyeing result can be predicted as the hue difference and sharpness difference from the liquid color difference of the sample dye determined in . Next, the present invention will be explained with reference to Examples. Example 1 [Measurement of liquid color difference of sample dye] Color Index No. Reality Red 112, which is a reactive dye, was first subjected to spectrophotometric analysis using a standard dye used as a quality standard and a 0.0025% aqueous solution of the sample dye. The absorbance curve in the wavelength range of the visible spectrum is measured. In FIG. 1, 1 is for the standard dye and 2 is for the sample dye. Using these absorbances, according to general formula (1),
Concentration tristimulus values for standard and sample dyes
Find QX, QY, QZ. The concentration tristimulus values QX, QY, QZ of the standard dye are QX = 9.6600 QY = 23.2810 QZ = 23.4630. The concentration tristimulus values QX, QY, QZ of the sample dye are QX=9.6040 QY=23.2120 QZ=23.5060. Next, using these values, the complementary color chromaticity coordinates, xQ, yQ, color density value SQ, etc. are determined by equation (2). The complementary chromaticity coordinates xQ, yQ and the color density value SQ for the standard dye are: SQ=56.4040 xQ=xQ(0)=0.1713 yQ=yQ(0)=0.4128 The complementary chromaticity coordinates xQ, yQ and the color density value for the sample dye are The color density values SQ are SQ = 56.322 xQ = 0.1705 yQ = 0.4121 When a complementary color chromaticity diagram is created using these obtained results, it becomes as shown in Figure 2. Here, the second
In the figure, 1 is for the standard dye and 2 is for the sample dye. Further, after converting the absorbance curve of a standard dye of the same type into a transmittance curve using equation (3), the tristimulus values X, Y, and Z are determined using equation (4). X=78.0150 Y=64.0219 Z=66.7220 Next, using equation (5), the color system is converted into an isometric color system, for example, the CIE1976 (L ^* a ^* b ^* ) color system recommended by CIE. L ^* (0) = 84.0114 a ^* (0) = 37.5735 b ^* (0) = 1.7272 In the a ^* b ^* chromaticity coordinates of this color system, the chromaticity point that gives the hue difference and saturation difference or sharpness difference a ^*
Chromaticity points a ^* (1), b ^* (1), a ^* (2), b ^* (2), a ^* (3) where (0), b ^* (0) change by 1 unit amount independently ), b ^* (3),
Find a ^* (4) and b ^* (4). (Figure 3) L ^* (1) = 84.0114 a ^* (1) = 37.6194 b ^* (1) = 0.7283 L ^* (2) = 84.0114 a ^* (2) = 37.5276 b ^* (2) = 2.7262 L ^* ( 3)=84.0114 a ^* (3)=38.5725 b ^* (3)=1.7731 L ^* (4)=84.0114 a ^* (4)=36.5746 b ^* (4)=1.6813 Then, the four sets given by these chromaticity points The tristimulus values of
The spectral transmittance curve Tλ giving each tristimulus value is determined by using computer color matching calculation for transmitted color. (4th ~
Figure 7) X(1)=78.0378 Y(1)=64.0219 Z(1)=67.9005 = 64.0219 Z(3) = 66.6681 2), the complementary chromaticity coordinates of each chromaticity point
Find xQ(1) to xQ(4) and yQ(1) to yQ(4). xQ(1)=0.1729 yQ(1)=0.4179 xQ(2)=0.1696 yQ(2)=0.4077 xQ(3)=0.1677 yQ(3)=0.4156 xQ(4)=0.1749 yQ(4)=0.4100 With this , the complementary chromaticity coordinates given by the above standard dyes
xQ(0), yQ(0) and complementary color chromaticity coordinates of each of the four chromaticity points found above xQ(1) to xQ(4), yQ(1) to yQ
Find the relationship and relational expression of the difference with (4). (Figure 8) △xQ(1)=xQ(1)−xQ(0)= 0.0016 △yQ(1)=yQ(1)−yQ(0)= 0.0051 △xQ(2)=xQ(2)− xQ(0)=−0.0017 △yQ(2)=yQ(2)−yQ(0)=−0.0051 △xQ(3)=xQ(3)−xQ(0)=−0.0036 △yQ(3)=yQ (3)−yQ(0)=0.0028 △xQ(4)=xQ(4)−xQ(0)=0.0036 △yQ(4)=yQ(4)−yQ(4)−yQ(0)=−0.0028 In Figure 8, 0 is the complementary chromaticity coordinate for the standard dye, and 1, 2, 3, and 4 are 1/5 times the difference between each complementary chromaticity coordinate and the complementary chromaticity coordinate of the standard dye. It shows. Next, in Figure 8, from the complementary chromaticity coordinates of the sample dye, take the average of the slope of the straight line connecting chromaticity points 0 and 1 and the slope of the straight line connecting chromaticity points 0 and 2, and Using the gradient, draw a parallel line to the straight line passing through the chromaticity point 0 (in this case, you may use a straight line connecting the chromaticity points 0 and 2, hereinafter referred to as the equal sharpness line), and draw a parallel line to the chromaticity point 0. Take the average of the slope of the straight line connecting chromaticity points 0 and 3 and the slope of the straight line connecting chromaticity points 0 and 4, and use this average slope to calculate the straight line passing through chromaticity point 0 (in this case, between chromaticity points 0 and 3). The coordinates of the intersection point A with the connecting straight line (hereinafter referred to as the isohue line) may be determined. xQ(A)=0.1708 yQ(A)=0.4132 Similarly, from the complementary chromaticity coordinates of the sample dye, draw a parallel line to the equal hue line and find the intersection B with the equal visibility line. xQ(B)=0.1710 yQ(B)=0.4117 Using these values, the liquid color hue difference and liquid color sharpness difference to calculate the liquid color difference are as follows. [Measurement of dyeing color difference of representative samples] Representative samples of the same dye as the standard dye
Dissolve 0.2 parts in 200 parts of water, add 20 parts of mirabilite, and mix with cotton.
Add 10 parts and raise the temperature to 50°C. After 30 minutes, 4 parts of soda carbonate is added and dyed at the same temperature for 1 hour. After dyeing, the dyed product is washed with water, soaped, and dried, and the dyed color difference of a representative sample of the same item of dye is calculated as the hue difference and saturation difference or sharpness difference between the dye that is the standard dye. Find the color difference. [Measurement of the liquid color difference of a representative sample] According to the method described above, the dye liquid color difference is determined by using the liquid color difference of a representative sample of the same item of dye with respect to the standard dye as the hue difference and sharpness difference. [Determining the relationship between the dye staining color difference and the liquid color difference of a representative sample] Using these dye staining color differences and liquid color color differences, regression analysis is performed to determine the relationship between the dye staining color difference and the liquid color difference of the representative sample using a regression line. Find it as. (FIG. 9) Using the previously determined liquid color difference of the sample dye, a predicted value of the dyeing result was determined from a regression line. The results are listed in Table 1 together with the color difference obtained by actually dyeing the sample dye.

[Table] Table 2 shows the results of the predicted dyeing values obtained using different sample dyes 1 to 8 in the same manner as above, in comparison with the actual dyeing results.

【table】

[Table] As shown in the above experimental results, the predicted value of the staining result obtained by the above method (predicted staining value) is in very good agreement with the value actually obtained by staining (staining result). Indicated. Example 2 Among disperse dyes that are poorly soluble or insoluble in water, Color Index No. Disperse Blue 301 was prepared by adding 80% acetonitrile to 0.005 part of the standard dye and sample dye used as quality standards. A solution made by adding and dissolving 100 parts is subjected to spectrophotometric analysis to measure the absorbance curve in the visible spectrum wavelength range. In FIG. 10, 1 is for the standard dye and 2 is for the sample dye. Using these absorbances, according to general formula (1),
Determine the concentration tristimulus values QX, QY, and QZ for the standard dye and sample dye. The concentration tristimulus values QX, QY, QZ of the standard dye are QX = 54.1590 QY = 54.1490 QZ = 16.2530. The concentration tristimulus values QX, QY, QZ of the sample dye are QX=54.3260 QY=54.6040 QZ=16.6620. Next, using these values and using equation (2),
Determine complementary color chromaticity coordinates xQ, yQ and color density value SQ. The complementary chromaticity coordinates xQ, yQ and color density value SQ for the standard dye are: SQ=124.5610 xQ= 0.4348 yQ= 0.4347 For the sample dye, 3SQ=125.5920 xQ= 0.4326 yQ= 0.4348 Using these obtained results, If we create a complementary color chromaticity diagram, it will look like the one shown in Figure 11. Here, the first
In Figure 1, 1 is for the standard dye and 2 is for the sample dye. Further, after converting the absorbance curve of a standard dye of the same type into a transmittance curve using equation (3), the tristimulus values X, Y, and Z are determined using equation (4). X=30.141 Y=32.058 Z=74.119 Next, using equation (5), the color system is converted into an isometric color system, for example, the CIE1976 (L ^* a ^* b ^* ) color system recommended by CIE. L ^* (0) = 63.4180 a ^* (0) = - 0.9732 b ^* (0) = -39.8531 Color that gives hue difference and saturation difference or sharpness difference in a ^* b ^* chromaticity coordinates of this color system degree a ^*
Chromaticity points a ^* (1), b ^* (1), a ^* (2), b ^* (2), a ^* (3) where (0), b ^* (0) change by 1 unit amount independently ), b ^* (3),
Find a ^* (4) and b ^* (4) (Figure 12). L ^* (1) = 63.4180 a ^* (1) = - 1.9730 b ^* (1) = -39.8286 L ^* (2) = 63.4180 a ^* (2) = 0.0264 b ^* (2) = -39.8775 L ^* (3) = 63.4180 a ^* (3) = − 0.9977 b ^* (3) = −40.8528 L ^* (4) = 63.4180 a ^* (4) = − 0.9489 b ^* (4) = −38.8534 Then, these chromaticity points give Four sets of tristimulus values X(1) to (4), Y(1) to (4), and Z(1) to Z(4) are obtained by inverse transformation of equation (5). X(1)=29.8769 Y(1)=32.0580 Z(1)=74.0881 X(2)=30.4067 Y(2)=32.0580 Z(2)=74.1496 X(3)=30.1345 Y(3)=32.0580 Z( 3)=75.3838 (13th to 116th
figure). These spectral transmittance curves Tλ are calculated using equation (3),
Convert to an absorbance light curve, and use equations (1) and (2) to calculate the complementary chromaticity coordinates xQ(1) to xQ(4), yQ(1) to yQ(4) of each chromaticity point.
seek. xQ(1)=0.4324 yQ(1)=0.4303 xQ(2)=0.4288 yQ(2)=0.4314 xQ(3)=0.4343 yQ(3)=0.4335 xQ(4)=0.4271 yQ(4)=0.4282 With this , the complementary chromaticity coordinates given by the above standard dyes
The difference △xQ(1) to △xQ between xQ(0), yQ(0) and the complementary color chromaticity coordinates of each of the four chromaticity points obtained above
(4), find △yQ(1) to △yQ(4) and the relational expression. △xQ(1)= 0.0018 △yQ(1)=−0.0006 △xQ(2)= 0.0018 △yQ(2)= 0.0005 △xQ(3)= 0.0037 △yQ(3)= 0.0026 △xQ(4)=− 0.0035 △yQ(4)=-0.0027 Next, as described in Example 1, obtain the equal hue lines and equal brightness lines, and draw parallel lines to the equal brightness lines from the complementary chromaticity coordinates of the sample dye. Find the coordinates of the intersection point A with the equal hue line. xQ(A)=0.4349 xQ(A)=0.4347 Similarly, from the complementary chromaticity coordinates of the sample dye, draw a parallel line to the equal hue line and find the intersection B with the equal visibility line. xQ(B)=0.4325 yQ(B)=0.4348 Using these values, calculate the liquid color difference. The liquid color hue difference is: Hue difference = 0.00228/0.0019 = 1.20 The liquid color sharpness difference is: Sharpness difference = 0.000045/0.0045 = 0.01 Also, add 0.2 parts of a representative sample of the same dye as the standard dye to 300 parts of water. Polyester spun type 10
and stain for 60 minutes at 130°C under pressure.
After dyeing, the dyed product is washed with hot water, further reduced washed and dried, and the dyed color difference of a representative sample of the same item of dye is calculated as the hue difference, chroma difference, or sharpness difference. , determine the dye staining color difference. On the other hand, by the method described above, the dye liquid color difference is determined by using the liquid color difference of a representative sample of the same dye with respect to the standard dye as the hue difference and the sharpness difference. Regression analysis is performed using these dye staining color differences and liquid color differences, and the relationship between the dye staining color differences and the liquid color differences is determined as a regression line. Using this relational expression, dyeing hue difference = 0.16 × (liquid color hue difference), dyeing sharpness difference = 0.28 × (liquid color sharpness difference), the predicted value of the dyeing result from the liquid color color difference of the sample dye obtained previously. I asked for The results are listed in Table 3 along with the color difference obtained by actually dyeing the sample dye.

[Table] Table 4 shows the results of the predicted staining values obtained using other samples 1 to 8 in the same manner as above, in comparison with the actual staining results.

【table】

[Table] As shown in the above experimental results, the predicted value of the staining result obtained by the above method (staining predicted value) is in very good agreement with the value actually obtained by staining (staining result). Ta.

[Brief explanation of drawings]

Figures 1 to 9 are CI Reactive Red 112
Regarding, Figures 10 to 16 are CI dispersion.
This is shown for Blue 301. 1st
10 are absorbance curves, and FIGS. 2 and 11 are complementary chromaticity diagrams, in which 1 is for the standard dye and 2 is for the sample dye. Figures 3 and 12 are chromaticity diagrams of the CIE1976L ^* a ^* b ^* color system, and 0
is the standard dye chromaticity point 1, 2, 3, 4 is the chromaticity point 0
This is the chromaticity point when the is changed by 1 unit amount independently. Figures 4 to 7 are spectral transmittance curves corresponding to each chromaticity point shown in Figure 3, and 0, 1, 2, 3, and 4 are spectral transmittance curves corresponding to the chromaticity points shown in Figure 3.
This corresponds to the chromaticity points shown in the figure. Figure 8 shows the complementary color chromaticity coordinates obtained from Figures 4 to 7.
is the standard dye, 1, 2, 3, 4 are the 4th to 7th dyes.
The numbers and x marks in the figure are for the sample dyes. FIG. 9 is a relational expression between the dye color difference and the liquid color difference. 13 to 16 are spectral transmittance curves corresponding to each chromaticity point shown in FIG. 12 calculated using computer color matching calculation for transmitted colors, and 0, 1, 2, 3, 4 are This corresponds to the chromaticity points shown in FIG.

Claims (1)

[Claims] 1. In testing the color properties of dyes and measuring the color difference between a sample dye and a standard dye, solutions of the standard dye and a representative sample of the same dye are prepared. Prepare each, measure the absorbance light curve, calculate the concentration tristimulus values QX, QY, QZ using absorbance instead of transmittance according to the usual tristimulus value calculation method, and then calculate the complementary color chromaticity. Find the coordinates xQ, yQ and color density value. In addition, one dye is arbitrarily selected from among the dyes of the same item mentioned above, its transmittance curve is measured, tristimulus values X, Y, and Z are obtained from this, and then an appropriate isochromic difference Convert to color system.
In this color system, the four sets of tristimulus values given by the chromaticity points are obtained when the hue difference, saturation difference, or sharpness difference is changed by a unit amount independently, and the transmittance curve corresponding to these values is mixed. This is determined by calculation using a calculation method, these are converted into an absorbance light curve, and the complementary color chromaticity coordinates of each chromaticity point are determined. From the coordinate difference between this and the complementary color chromaticity coordinates of the dye arbitrarily selected above, the relationship between the hue difference and chroma difference or the sharpness difference and the complementary color chromaticity coordinate difference in the isochromatic color system is clarified. Keep it. Using this relationship, the hue difference and sharpness difference are determined from the liquid color difference of the representative sample of the same item of dye with respect to the standard dye, and these are used as the dye liquid color difference. From the dyeing color difference of the representative sample of the same item of dye with respect to the standard dye of the dyed products obtained by dyeing using the representative sample of the same item of dye as the standard dye, the color is determined. The phase difference and saturation difference or sharpness difference are determined and used as the dye dyeing color difference. By statistical method, the color difference of dye liquid color and
Find the relationship between dye staining color difference. The dye solution color difference is determined as a hue difference and a sharpness difference in the same manner as in the above-mentioned method of determining the dye solution color difference of the sample dye of the same item with respect to the standard dye. From the dye liquid color difference of the sample dye of the same item with respect to the standard dye described above, using the relationship between the dye liquid color difference of and the dye dyeing color difference obtained in , A method for measuring a dye color difference, comprising predicting a dye dyeing color difference of the sample dye.