Google feline color vision
Plenty of hits, such as this one:

http://www.cathealth.com/CatEyes.htm

Cones and Color Vision

The end result is that cats have poor detail vision compared to humans. And because cones are also responsible for color vision, cats have comparatively poor color vision. But they’re not colorblind. Instead, they have the same type of color vision as many people who are called colorblind: a type of red-green colorblindness termed deuteranopia. They can see blue versus other color fine, but tend to confuse colors on the red through brown through green continuum.

I have long read that cats do not see red. Nevertheless, several of my cats have also have favorite RED toys, blankies etc. Other cats are partial to the black ones. Haven't noticed any other color preferences.