No more color coatings at present. I am having a problem with mordanting the dyes. They tend to dissolve in the developer so I have to get them to stay put. Alum was my first bet, but I cannot coat it easily without crosslinking the gelatin as well as mordanting the dye. So, experiments continue, but I have no progress to report. I have searched a lot of old patents though.
I find, as I expected, that the mordants we used at EK were often custom made.