Hypercat was developed by Jay DeFehr as a high acutance, catechol-based tanning/staining developer. Mixed in glycol, it has a long shelf life.
|Ascorbic Acid||1 g|
|Propylene Glycol||100 ml|
|Distilled water||750 ml|
|Distilled water to make||1 L|
People dilute this developer from 1:1:100 to 1:1:500.
You can learn more from Jay’s Hypercat forum.