CONFLICTING REPORTS RE EMULSION

[AJLA]

Is the emulsion used on screens light sensitive when wet?

[John G]

Hi,
Once sensitised the emulsion is light sensitive. I have heard of printers coating screens in normal light but my opinion is that everytime the lid comes off the emulsion, in normal light, its going to set off the reaction and weaken the mixture. I always coat my screens in a dark room with a safe light and store my emulsion and unexposed screens in a light proof box in the dark room.

Cheers John

[AJLA]

What kind of light are you using John because the positioning of possies is quite difficult .

[John G]

No - what I mean is I coat and store my screens in the dark with a safe light on. When it comes to exposing a screen my exposure unit is in the main printshop, it only takes seconds to get the right position then switch the light on so any light hitting the screen won't matter.

My safe light is homemade - a normal household bulb fitted in a recess in the ceiling with a sheet of amber covering it. Amber is an old fashioned stencil material that could be hand cut or cut on a plotter to make basic stencils. Its light proof so makes ideal safe lights. Amber is from the year 1066 , just so happended to have a few offcuts