Most dyers over fix anyay, dripak is cheaper and its alot more accessible for most ppk to get hold of, and its incredibly cheap in bulk. Under 50p a kilo.
Anyway, its nothing really to do with the amount of fixer, its to do with the relationship between tempertuare and ph.
The idea is that you push the ph up as far as you can with the soda ash and heat. All you need is a ph monitor, or cheaper still buit not very accurate, litmus paper. You need 30 degrees and above for procion mx dyes. The warmer the water and sodium carbonate solution, the higher the ph... so starting as hot as you the material can take, the reaction takes place quickly, and as it cools the ph drops, dye can still fix as low as 30 degrees celcius. Starting hotter means you dont need as much sodium carbonate to up the PH too. Sodium carbonate's solubility is around 22 grams per 100ml of water at 20 degrees.. you need warmer water for it to be soluble.. anyway.........
Cloth Nappy Tree gives you a free, unbiased and privacy rich place to discuss and recycle your cloth nappies. Save time, money and our planet by inspiring and helping others.