Who defines, that spraying (or wire application) of a soldermask is incorrect? Screen printing can be only applied for low resolution standard technologies. It's legacy at most PCB manufacturers. High resolution can be provided by laminated dry film or liquid resist. The latter will necessarily fill through plated vias and terminal pads, and also have a ring of slightly increased thickness around them, what you call "spill".What I see is the spills of the soldermask around the vias whcih can happen if they don't apply properly the solder mask (instead of silkscreen they use spraying so liquid soldermask is sucked into via hole because of capilar effects).
Screen printing of solder masks achieves a limited position accuracy of about 0.1 mm / 4 mils, so it isn't used by any manufacturer for high resolution SMT PCBs, as far as I'm aware of. Don't want to repeat the other points, that have been already said.
That sounds more plausible. However, none of the major PCB manufacturers I've been working with is using this technique. They are mainly using automated courtain coating machines. I assume, that there are viscosity differences between liquid coating and screen printing material, in so far the finish may look different. But screen printing isn't the industry standard.Actually the photoresist solder mask is applied with silkscreen printing method and then exposed on UV
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