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Accelerated artificial aging of ZnO PW4 acrylic artist’s paints was carried out for a total of 1963 hours (~8 107 lux.h) with aging assessment at specific intervals. Color change ΔE* < 2 (CIELab-76 system) over 1725 hours of aging, while the human eye notices color change at ΔE* > 2. Oxidative degradation of organic components in the paint to form volatile products was revealed by ATR-FTIR, Raman spectroscopy-microscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). It appears that deep oxidation of organic intermediates and volatilization of organic matter may be responsible for the relatively small value of ΔE* color difference during aging of the samples. To elucidate the degradation pathways, principal component analysis (PCA) was applied to the spectral data, revealing: 1) the catalytic role of ZnO in accelerating photodegradation, 2) the Kolbe photoreaction, 3) the decomposition of the binder to form volatile degradation products, 4) the relative photoinactivity of CaCO3 compared to ZnO, showing slower degradation in areas with higher CaCO3 content compared to those dominated by ZnO. These results provide fundamental insights into formulation-specific degradation processes, offering practical guidance for the development of more durable artist paints and conservation strategies for acrylic artworks.