Metal plate for manufacturing deposition mask and manufacturing method for metal plate, and deposition mask and manufacturing method for deposition mask

A manufacturing method for a metal plate used for manufacturing a deposition mask, the method comprising:

• a rolling step of rolling a base metal to obtain a metal plate that includes pits located in the surface of the metal plate as a result of the rolling step,
• an inspection step of inspecting an inspection area on the surface of the metal plate, and
• a modified rolling step of rolling the metal plate using adjusted rolling conditions based on results obtained from the inspection step to obtain a modified metal plate,
• wherein the surface of the metal plate includes the inspection area having an area of 0.1 mm2 or more with some of the pits being located in the inspection area, and
• wherein said inspection step comprises a calculation step of calculating a corrected pit volume density;
• and
• wherein said modified rolling step includes adjusting the rolling conditions so that the corrected pit volume density of the modified metal plate is equal to or less than a first threshold of 15,000 μm3/mm2;
• wherein the corrected pit volume density is calculated by dividing a corrected pit volume by the area of the inspection area;
• wherein the corrected pit volume is a sum of volumes of parts of the pits located in the inspection area, said parts of the pits being a correction distance of 0.2 μm or more away from the surface in the thickness direction of the metal plate.