What’s difference between pigment and dye ink?

When we buy TIJ (thermal inkjet ink) ink, we find that the ink of same color always both in pigment and dye based. What’s the difference between them? Pigment ink is composed of molecules, its molecular diameter is much larger than dye ink. It’s waterproof, sunscreen, and have a high contrast on black or other dark surfaces. Because of its large molecular diameter, its raw materials are difficult to make. The price of TIJ pigment is high, and it’s easier to block nozzles than dye ink. Dye ink is a complete composite solution, not easy to block nozzles, the price is lower, but it’s not waterproof, and no contrast when coding on black and other dark surfaces. Therefore, if you don’t need waterproof and not printing on dark surface, choose dye ink is ok.