[nassif.bousaba]

Hello,

I tried to dye DEG solution (pale yellow/white color) with a blue dye.
The blue color was good at the start, however after one month I could start noticing that the color started fading away until there was no color at all.

The solution is exposed to heat (~40 degree Celsius) during the day.

Can you please explain why is this happening?

[Borek]

Depends on the dye, not knowing what it was it is impossible to say anything.

Many dies are not stable, they get destroyed by UV or oxygen, or just decompose, this is to some extent their inherent property related to the presence of chromophores, which need to be easily excited.

[rolnor]

Is not whiper-fluid for cars blue? Can you use the same colorant?