I suspect you mean PURPLE.
Green is the "wicking" locktite, meant to apply after the hardware is torqued, and requires heat to remove according to the mfg.
Blue is heatless-removal. "Normal" locktite.
Purple is "small screw", easier to crack loose than blue. also good for soft-metal hardware.
Red requires heat and tools to remove.
http://henkeladhesivesna.com/blog/the-difference-between-red-blue-green-and-purple-threadlockers/