What is the difference between blue and green material chests for APC upgrades?

Green chests give green materials and blue chests give blue materials. Blue materials are better. But you will get less of them.

In the Parts Factory -> depot you are able to combine materials into higher levels.

4 white = 1 green

4 green = 1 blue

4 blue =1 purple

4 purple = 1 orange

4 orange = 1 gold

The chests usually give 4 times more green materials than blue so the value of materials is the same overall.