21 step sensitivity guide expose ruler for exposure machine
21 step sensitivity guide expose ruler for exposure machine
21 step sensitivity guide, is necessary tool for high accurate exposure energy control, on liquid PISM line ink and PISM solder mask ink during printed circuits board production.
brand: Stouffer
application and usage
Taking the diazo sheet as an example, the quality of the diazo sheet directly affects the quality of the finished circuit board. Generally, the silver salt sheet is used as the master sheet, and the diazo sheet is made by copying. In order to ensure the quality of the diazo film before copying, a 21-level exposure ruler is generally used to adjust the exposure energy.
Place the exposure ruler directly on the glass surface, place the diazo sheet on the exposure ruler, and then cover the diazo sheet with an opaque material (such as black paper) for exposure. When the exposure is completed, let the diazo film through the developing machine at least twice, and read the clearest grid number (or the lightest grid number). If the first grid is completely transparent, and the second grid is clear or very light red or the remaining grids will gradually deep and reach saturation, then the energy is considered to meet the requirements.
If the above requirements are not met, the energy can be increased according to the following access. If the energy value of the exposure machine is 350, the third grid can be obtained clearly, and the energy reading should be adjusted to 227 (350*0.65) before testing. Generally, the requirements of the target can be obtained.
Taking the outer layer process of the PCB circuit board as an example, the production process of the exposure ruler: take the dry film as an example, copper clad laminate - pretreatment - lamination - exposure ruler to place the board surface (set appropriate equipment parameters) exposure - development - washing - Check to confirm the exposure scale level, that is, take readings by observing the dry film residual condition on the exposure scale pattern after development. The standard grade of dry film is grade 6-8.
