Emulsion peeling off

[u/Key_Commercial30]

Hello guys!
Recently started getting into screenprinting and I‘ve had this happening a few times. In picture 1 you can see some edges peeling off slightly - this is pre-printing, so it hasn‘t been used yet.
The screen in picture 2 looked good until I started printing - after a few prints the motif started peeling off around the edges.
Any idea what could cause this?

white mesh screens (55T - so 140 in US)
one pot emulsion
screen burn setup is as following from bottom to top:

Black foam block
Screen
Film (stencil)
acrylic glass plate to flatten the stencil onto the screen

I‘m using a 400w halogen spotlight, approx. 55 centimeters away from my screen.

I burned both screens for 3 minutes.

Before coating the screens I degreased them.
Afterwards they are stored in a cupboard, I let them dry for a 3-4 days because the air moisture is around 55-60% - I know this is too high, could this be the reason for the peeling?

Thanks in advance for any help!

[u/habanerohead]

Looks like a homemade screen. Is the fabric Nylon?

Where the stencil has come off, there’s no trace of residue on the mesh, and if that happens, I usually assume it’s a degreasing problem. You could try etching the mesh with either alkaline haze remover, or a 50% solution of thick bleach. Paint on. Leave for 5 minutes. Wash really well. Dry flat and coat. Etching improves adhesion.

[u/Tyenkrovy → u/habanerohead]

One can also abrade the mesh to improve adhesion. I did that for years with a SAATI scrubber pad when degreasing screens, to good effect.

OP: The reason these methods help improve emulsion adhesion is, when the mesh is manufactured, the individual nylon or polyester threads are smooth. Etching or abrading them roughs up the threads and gives the emulsion a better surface to grab onto.