Production method for metal plates for vapor deposition masks

A method for manufacturing a deposition mask, comprising:

• a step of preparing a metal plate having a plurality of crystal grains;
• a step of transporting the metal plate along a longitudinal direction;
• a step of forming through-holes in the metal plate;
• and
• a step of calculating an average crystal grain cross-sectional area of the plurality of crystal grains of the metal plate by analyzing measurement results obtained by an electron backscatter diffraction patterns method, the measuring results being analyzed by an area method under conditions where a portion with a difference in crystal orientation of equal to or more than 5 degrees is recognized as a crystal grain boundary,
• wherein the metal plate is made of a rolled iron alloy and has a thickness of equal to or less than 15 μm,
• wherein the average crystal grain cross-sectional area, as analyzed by the area method on a cross section of the metal plate, is from 0.5 μm2 to 15 μm2, the cross section having an angle of from −10° to +10° with respect to a plane perpendicular to a rolling direction of the metal plate, and
• wherein the rolled iron alloy consists of 30% to 38% by mass of nickel and 0% to 6% by mass of cobalt, with the balance being iron and unavoidable impurities.