Advantages and disadvantages of dry film mask technology method, why it would happen open holes?

Advantages: it has high manufacturing precision and neat edges, process easy to control. It is suitable for the production of PCB boards with high precision requirements, such as double-sided boards, multilayer boards and high-frequency PCB, HDI with dense circuit in small batches and varieties. Moreover, it uses less water and is easy to control, which is very conducive to environmental protection.