Polyester-resin-coated seamless can and method for manufacturing the same

A seamless can in which a polyester resin coating is formed on at least an outer surface of a metal sheet, the seamless can comprising:

• a reduced diameter portion obtained by neck processing within a distance of 0% to 15% from a can body uppermost portion with respect to a total height of the seamless can from the can body uppermost portion to a can bottom of the seamless can,
• wherein a ratio Im/Iu is 1.0 or more, where Iu is a value (cps/μm) calculated by dividing a maximum value of peak intensity in a range satisfying 15°≤20≤19° of an outer-surface polyester resin coating based on an X-ray diffraction method at a measurement site in a maximum reduced diameter portion of the reduced diameter portion by a thickness of the polyester resin coating at the measurement site, and Im is a value (cps/μm) calculated by dividing a maximum value of peak intensity in a range satisfying 15°≤20≤19° of an outer-surface polyester resin coating based on an X-ray diffraction method at a measurement site within a distance of 45% to 60% from the can body uppermost portion by a thickness of the outer-surface polyester resin coating at the measurement site.