Poor development of PCB circuit boards has always been a common problem faced by manufacturers and the manufacturing industry. With the continuous development and complexity of electronic devices, the requirements for circuit boards have become increasingly high. The problem of unclear development on the circuit board not only affects the quality and performance of the product, but also may lead to functional failure of the product. It is very important to understand the reasons for unclear development and find solutions.

　　1. Developer contamination: Developer is an indispensable part of the development process of circuit boards, which can remove uncured photosensitive adhesive. However, if the developer is contaminated, such as the presence of precipitates, metal particles, or other impurities, it can lead to unclean development.

　　Solution: Regularly replace the developer and ensure that its quality and purity meet the requirements. At the same time, before using the developer, it should be filtered and tested to avoid contamination.

　　2. Uneven application of photosensitive adhesive: Photosensitive adhesive plays a crucial role in manufacturing PCB circuit boards, as they form patterns through photosensitive reactions. If there are problems with the photosensitive adhesive during the coating process, such as uneven coating or voids, it can lead to different levels of development in different parts during the development process, resulting in the problem of unclear development.

　　Solution: Regularly check and update the photosensitive adhesive coating equipment to ensure its normal operation and provide uniform coating. In addition, use high-quality photosensitive adhesive and ensure that its storage and use meet the requirements to avoid quality issues.

　　3. Inappropriate development time: The concentration of development solution and development time are very important factors in the development process. If the development time is too long or too short, it can lead to the problem of unclear development. A short time may lead to incomplete development, while a long time may cause corrosion of the development solution in other areas, resulting in impurity.