Coating composition
View Patent ↗A colored coating composition comprising a white base paint and at least one colored pigment in a form that can be readily mixed with the white base paint, the white base paint comprising a film-forming polymer, a liquid carrier, one or more opacifying white pigments and one or more extenders, the colored coating composition having a light reflectance value Y less than 110, and greater than that defined by the equation Y=mC+K, where 25>C>1.0, C being the chroma of the colored coating composition, m and K being empirical coefficients selected according to the type and number of the type of the at least one colored pigment, and dependant on the hue angle of the coating composition.
1. A colored coating composition comprising a white base paint having a minimum light reflectance value of 93, and at least one colored pigment in a form that is mixed with the white base paint, the white base paint comprising a film-forming polymer, a liquid carrier, one or more opacifying white pigments and one or more extenders, the colored coating composition having a light reflectance value Y less than 110, and greater than that defined by the equation:
Y=mC+K,
where 25>C>1.0, C being the chroma of the colored coating composition, m and K being empirical coefficients selected according to the type and number of the type of the at least one colored pigment, and dependent on the hue angle of the coating composition,
wherein m and K determine a minimum colored coating composition light reflectance value relating to a color region A between this minimum and 110, m and K being defined according to the following table:
Hue
angle °
m_A
k_A
0
−1.364
91.713
10
−1.356
91.952
20
−1.443
91.757
30
−1.387
92.262
40
−1.305
92.703
50
−1.209
93.071
60
−1.113
93.440
70
−1.017
93.808
80
−0.822
94.732
90
−0.485
93.225
100
−0.330
92.357
110
−0.525
92.872
120
−0.719
93.386
130
−0.919
93.803
140
−0.945
93.661
150
−0.970
93.520
160
−0.996
93.378
170
−1.034
93.238
180
−1.127
93.104
190
−1.220
92.971
200
−1.312
93.086
210
−1.513
92.208
220
−1.745
91.330
230
−1.980
90.509
240
−1.949
90.197
250
−1.919
89.886
260
−1.888
89.575
270
−1.858
89.263
280
−1.827
88.952
290
−1.797
88.641
300
−1.799
88.878
310
−1.840
89.482
320
−1.808
89.998
330
−1.450
91.389
340
−1.360
91.340
350
−1.362
91.526
360
−1.364
91.713
or, m and K determine a minimum colored coating composition light reflectance value relating to a color region B between this minimum and 110, m and K being defined according to the following table:
Hue
angle °
m_B
K_B
0
−1.650
90.213
10
−1.643
90.452
20
−1.587
90.957
30
−1.581
87.462
40
−1.433
91.903
50
−1.337
92.271
60
−1.267
89.640
70
−1.145
93.008
80
−0.911
93.432
90
−0.553
92.425
100
−0.355
91.557
110
−0.558
88.072
120
−0.743
92.586
130
−1.006
93.003
140
−1.032
92.861
150
−1.057
92.720
160
−1.083
92.578
170
−1.131
92.438
180
−1.224
92.304
190
−1.317
92.171
200
−1.410
92.286
210
−1.643
91.408
220
−1.874
90.530
230
−2.169
89.709
240
−2.138
89.397
250
−2.145
86.086
260
−2.077
88.775
270
−2.047
88.463
280
−2.016
88.152
290
−1.985
87.841
300
−1.968
88.078
310
−2.009
88.682
320
−1.986
89.198
330
−1.806
89.889
340
−1.646
89.840
350
−1.648
90.026
360
−1.650
90.213
wherein for color region A the at least one colored pigment is:
a maximum of two organic colored pigments in significant quantities, and there is a maximum of 0.015 wt % of carbon black pigment relative to the total dry weight of the colored coating composition, or
a maximum of one inorganic pigment in a significant quantity, and there is a maximum of 0.015 wt % of carbon black pigment relative to the total dry weight of the colored coating composition, or
one organic pigment, and one inorganic pigment, the organic pigment capable of producing a colored coating composition having a first hue, and the inorganic pigment capable of producing a colored coating composition having a second hue, the first and second hues being separated by a maximum angle of 20 degrees, and there is a maximum of 0.015 wt % of carbon black pigment relative to the total dry weight of the colored coating composition,
wherein for color region B, the at least one colored pigment is:
three or more organic colored pigments in significant quantities, and there is a maximum of 0.022 wt % of carbon black pigment relative to the total dry weight of the colored coating composition, or
two or more inorganic colored pigments in significant quantities, and there is a maximum of 0.022 wt % of carbon black pigment relative to the total dry weight of the colored coating composition, or
one organic pigment, and one inorganic pigment, the organic pigment capable of producing a colored coating composition having a first hue, and the inorganic pigment capable of producing a colored coating composition having a second hue, the first and second hues being separated by more than 20 degrees, and there is a maximum of 0.022 wt % of carbon black pigment relative to the total dry weight of the colored coating composition.
2. The colored coating composition according to claim 1 wherein the white base paint has a minimum light reflectance value (Y model ) of 93 defined by the selection of the one or more opacifying white pigments and one or more extenders according to the equation:
Y
model
=
A
+
w
·
〈
Y
〉
ext
+
F
·
(
1
-
w
)
·
〈
Y
〉
pig
w
+
(
1
-
w
)
·
F
where w is the weight fraction of the extender compared to the total weight of the one or more opacifying white pigments and one or more extenders, A and F are empirical coefficients with values of 0.785 and −0.0969 respectively, <Y ext > is the opacifying white pigments weight-averaged light reflectance value of the one or more extenders and <Y pig > is the weight-averaged light reflectance value of the one or more opacifying white pigments, the weight averaged light reflectance values being defined by the equations:
〈
Y
ext
〉
=
∑
i
w
i
·
Y
ext
∑
i
w
i
,
and
〈
Y
pig
〉
=
∑
i
w
i
·
Y
pig
∑
i
w
i
.
3. The colored coating composition according to claim 1 wherein at least one of the colored pigments is a fluorescent pigment capable of emitting light in a particular part of the visible spectrum such that it increases the chroma of the colored coating composition.
4. The colored coating composition according to claim 1 , the colored coating composition having a particular hue, the colored coating composition further including a photoluminescent compound capable of emitting light in a particular part of the visible spectrum such that it increases the chroma of the colored coating composition.
5. The colored coating composition according to claim 4 , wherein the photoluminescent compound is one or more of an optical brightener, a fluorescent pigment or a phosphorescent pigment.
6. The colored coating composition according to claim 5 wherein the optical brightener or the fluorescent pigment is dispersed in the white base paint of the colored coating composition.
7. The colored coating composition according to claim 1 wherein the colored coating composition is an architectural emulsion coating composition suitable for application to walls and/or ceilings.