Any good way to improve the retention of color?

Follow the correct procedure of how to use. Do cooling and emulsification very well, otherwise color goes away faster.

Is it possible to tone up the hair?

No. Natural Herb Color does not contain Alkaline agent as well as H2O2 so it is not possible to tone up.

Natural Herb Color contains Diamine?

Yes. It contains Diamines including p-phenylenediamine (PPD). A person who has diamine allergy must NOT be dyed by products.
Do a patch test for hours/days according to the law of your country.

What kind of effectiveness can we expect by using Natural Herb Color?

Promoting blood circulation of scalp, anti-aging and treatment on damaged hair.

How long does Natural Herb Color usually last after coloring?

It is like alkaline color, usually a month to a month and half.

Do we need heating when leaving the color after wrapping and wearing towel?

No. Leave in room temperature is fine.

Can we make warm the Aroma O2 water / O2 water?

Yes, it wouldn’t be a problem if you warm up the water.

Why do we have to use Aroma O2 water or O2 water instead of tap water?

Tap water contains chlorine and lots of impurities, which disturb the settlement of colorant and make the color life shorter on hair.

Aroma O2 water and O2 water do not contain chlorine and impurities, and more than that contains 3 time more of O2 compare to tap water. That is why the color lasts long.