At WEdirekt, we offer a green, photosensitive solder resist. Please note in your design, the following rule of thumb:
Solder Mask Pad Ø = Copper Pad Ø + 0,10mm
If your board has different values, we will adapt the layout to this rule of thumb. This is to be keep solder surfaces free of solder resist. Our recommended soldermask web is a minimum of 70μm.
You can download our solder resist datasheet here:
Remark: We use flexible solder mask for PCBs with a thickness of 0.50mm.