Try Other Color Combination
Since they were the primary colors, in the beginning they were cheapest. When the colors became more affordable, they just stuck with red, blue and yellow because that was what people were used to. The patriotic feel thing came later, because red and blue are pretty patriotic colours.
Colour used for associations in storytelling
The use of a color with an associative purpose means that a specific color and its scheme will be linked to a character or an idea throughout the film, letting the audience connect extra dots through the simple presence of a particular color.
