Application of cold pigments in coatings (3)

. 4. 2. 2 The chroma effect of the cold black pigment in the L-value increase (when diluted)
in the actual use process, in order to meet the requirements of the JG/T235-2014 standard, as the L-value increases, in the cold black pigment needs to be added Cold titanium white to improve the corresponding reflectivity and full reflectivity, Figure 5 shows the cold black pigment SPP-3025 in the use of ordinary titanium dioxide and 2 cold titanium white dilution, corresponding to the brightness of the L-value increase when the a-value and b-value changes.Figure 6 shows that cold black pigments differ in color using conventional titanium dioxide and cold titanium dioxide at different L-values. From Figure 6, it can be seen that the use of cold titanium white on cold black pigment dilution, and the use of ordinary titanium dioxide dilution contrast, in the same L- value, cold titanium white diluted color color will be red, yellow, visual feeling is not as pure as blue.This is the same as the color deviation problem that occurs when the high-brightness L-value is greater than 80, as black, in order to meet the requirements of the JG/T 235-2014 standard, if the use of cold titanium white dilution, as the most basic attribute color of black color will change, so it is recommended that some of the light L-value range of the standard requirements are necessary to revise the reflectivity limit.
4. 2. 3 Application of white natural sand in real stone paint sand
The main additions to real stone paint products are white natural color sand and artificial white color sand (see Table 4), there is currently no standard for cold products related to real stone paint and color sand, if JG/T 235-2 The standard of 014 requires the cold effect of real stone paint, and in practice, it is found that the natural white sand or artificial white sand (natural white sand and ordinary titanium white powder coated with artificial white sand) after the L-value of more than 70 is less than the requirements of the JG/T 235-2014 standard.for the real stone paint to conform to the JG/T 235-2014 standard, white sand must be covered with cold titanium paint when the value of L is greater than 70, but this results in a result such as 4. 2. 1 The phenomenon of white in the color and addition at high brightness——— the chromochal deviation (not pure, not blue white) that exists in white at high brightness.5 Conclusion
(1) There is a difference between cold pigments and cold effect pigments, and in practice, more attention is being paid to the need for solar reflectivity performance. But for cold pigments, the required triple attributes are indispensable: high masking color, excellent weather resistance, and high near-infrared reflectivity. Combined with some challenges in the implementation of the JG/T 235-2014 standard, it is recommended that when using cold pigments, not only have certain requirements for reflectivity, but also emphasize the requirements of high masking force and excellent weather resistance, so that cold pigments can be reasonably applied when used in practice.
(2) Composite inorgeable pigment MMO/CICP has excellent weather and temperature resistance, some pigments also have a good performance of reflecting solar thermal energy, so derived from the composite inorgeable pigment cold pigment system, more in line with the requirements of cold pigments.
(3) Combined with the problems in practical application, it is recommended to make the following corrections to the JG/T235-2014 standard: only emphasize that high near-infrared reflectivity will be more relevant to practical application;.