I am trying to print 1 color on top of another and am having bleeding ink problems. I'm Using Union Aerotex water based ink and 136 mesh screens. I uploaded a couple pics to show what is happening.
I think he's already flashing before the second color.
If it's bleeding on the second color, black, then try using a much higher mesh screen for that color, as you don't need to lay down nearly as much ink as you do when printing the white base.
I would use something like 230 for black waterbased ink on top of white. That Union Aerotex black is pretty thin and therefor prone to bleeding when you're using a low mesh screen, which allows too much ink to pass through. Try a 230 or something around there, and also be careful flooding and mindful of your squeegee techniques.
Union aerotex black will clog in a long print run, especially if it sits while you do another color, so a light flood stroke is appropriate, in my opinion/experience. An incomplete flood stroke requiring a second stroke to flood the entire stencil, that's what will get you into trouble with bleeding issues, so be sure to have adequate ink on the screen.
Color on color bleeding 
