Neutral Point in the Mixing of Complementary Colors

This study examined how hue-category–based color naming changes during desaturation through complementary mixing, with a focus on chromatic neutrals such as brown. Three continua(R–G, O–B, Y–P) were constructed by mixing the RYB primaries and their complementary colors in 10% increments, and 33 stimuli were presented to 43 adults with normal color vision to measure color naming. The point in each continuum where responses to the two hue categories were approximately equal at50%, indicating maximal ambiguity in naming, was defined as the “Neutral Point in the Mixing of Complementary Colors.” The neutral point occurred at the 50:50 mixture in the R–G continuum, where as it appeared at a 40:60 mixture biased toward Blue/Purple in the O–B and Y–P continua, indicating that the neutral point does not always coincide with the midpoint of the mixing ratio. These findings provide foundational data for identifying neutral points in the RYB mixing framework and serve as a basis for future research to test Warm–Cool judgments of chromatic neutrals using these neutral points as reference anchors.