Fluid container, recycling method of fluid container, and sealing method of fluid container

A method for recycling a fluid container, comprising:

• refilling a used fluid container through an opening to be sealed with a fluid, the opening to be sealed being one of a hole formed in the fluid container and a hole formed in a cover film welded or bonded to the fluid container in such a manner as to cover the hole:
• preparing a sealing member, the sealing member being a laminated film formed by laminating a plurality of films including a first film and a second film, wherein the first film is meltable at a predetermined heating temperature, and the second film is not meltable at the heating temperature and exhibits an improved heat resistance compared to the first film, the first film forming one of outermost layers of the laminated film, the second film forming the other of the outermost layers;
• placing the sealing member on the fluid container with the sealing member facing the fluid container in such a manner that the sealing member covers the opening to be sealed;
• and
• sealing the opening to be sealed with the sealing member by heating the sealing member covering the opening to be sealed from the side corresponding to the second film to melt the first film.