Optimal pH range for acid dyes?
  • What is the optimal pH for an acid dye to be most effective? I am immersion dying wool and would like to switch to citric acid solution for a pretreatment replacing vinegar. Suggestions? I would really like a pH range so I can test it. Thanks!
  • For levelling acid dyes, a PH of 2-4 is recommended, and for milling acid dyes, 4-7. An average of around 4 should be good for most acid dye applications.
  • I have been using citric acid and I think the amount we suggest in our directions puts you in the around 2-2.5. This can give some different colors depending on the color. I have noticed specifically that both Jet black and Olive give you browner colors in the 2 vs the 4 pH range. If you use less you get a better black and a better olive.

    I have dyed the whole line basically and there are small variations when the pH is a lot lower. I think the dyes work best around 4.

    I have found that 10g/L gives you a low 2 on the pH scale. Half that and you are around 3. So really 2-2.5g of citric acid per liter puts you at around 4, which I think is probably ideal.