Reflectance and color appearance of non-white cool concrete tiles for single- and double-layer coating methods
DOI:
https://doi.org/10.46421/encacelacac.v18i1.7134Keywords:
Cool roof, Solar absorptance, Titanium dioxide, Iron oxide, Reflective coatingAbstract
This paper investigates the influence of coating methods on the production of non-white cool concrete tiles. Measurements of spectral reflectance and color coordinates were performed on 60x60x11 mm mortar samples with coating in single- (SL, only colored topcoat) or double-layer (DL, white basecoat and colored topcoat). Solar reflectance (SR) was higher for DL and the white basecoat increased the samples’ SR in the 0.034 – 0.104 range, with a greater impact on near-infrared reflectance. Total color-differences between SL and DL are perceptible by human eyes. Although DL samples are lighter than SL ones, the color coordinates L*, a*, and b* are not different (p-value > 0.05, Student t-test). It can be concluded that coating methods influenced the samples' SR and color appearance, and the DL method is recommended for cool concrete tiles if small color changes are acceptable.
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