Shadow mask assembly manufacturing method and cathode ray tube manufacturing method

A method for manufacturing a shadow mask assembly in which a shadow mask that has an approximately rectangular sheet-like shape and a perforation region provided with a number of through holes is fastened to a support frame that has an approximately rectangular frame-like shape in a tensioned state of the shadow mask, the method comprising:

• applying a preliminary tension force of an strength of 9.8 to 490 N to each of four corners of the shadow mask outwardly aslant with respect to a side of the shadow mask;
• applying a main tension force to each of at least a pair of mutually opposite sides of the shadow mask outwardly perpendicularly to the sides after the preliminary tension force is applied thereto;
• and
• fastening the shadow mask to which the main tension force has been applied after applying the main tension forces to frame sides of the support frame.