Design and preparation of high color rendering red inorganic pigment via red light emission phosphor

In this paper, a new method to improve the color rendering performance of inorganic red pigment by adding phosphor is proposed. The optimal mixing ratios of (Ca,Sr)AlSiN3:Eu2+, (Sr,Ba)2Si5N8:Eu2+ and NaMgPO4:Eu2+ phosphors in the γ-Ce2S3 red material are 20%, 10% and 5%, respectively. At the optimal mixing ratios; L* increased by 12.9%, 3.5% and 3%, separately; a* increased by 4.3%, 4% and 1.6% severally; C* increased by 7.9%, 4.3% and 1.5% in turn. Of course, the different properties of the phosphors themselves make the mixing ratios different. Subsequently, the mechanism of pigment fluorescent materials is further investigated by using Chromatometer, SEM, Fluorescence Photometer, UV–vis Spectrophotometer and Fluorescence Microscope. The results shows that, under the irradiation of sunlight, the fluorescent materials in the fluorescent pigments are excited by the light of specific wavelengths in the sunlight, producing an asymmetric broad-band emission in the visible red region. The light emitted as a second light source is diffusely reflected by the pigment particles, which plays a superimposed effect and finally improves the color rendering ability of the red γ-Ce2S3 pigment that originally relies only on the reflected sunlight energy.