Why cant I use any heat with Redken lighteners? ( I get this question a lot ) First, Redken is developed by scientists who test this. So: 1. Its strong enough without any heat or dryer added. Follow mixing directions 2. Adding heat may lead to unpredictable results- ☄️Yowza! 3. The thickness or consistency may change while its processing 4. It may over process and break down the bonds inside hair and weaken it too much Note: We use bonder inside our lighteners now and bonding care along the way and also afterwards to re strengthen weakened hair strands while blonding. . Acidic Bonding Concentrate is a game changer for me. Questions? Dm @lorifudens_redkenartist anytime 💕 @redken @saloncentric