Patent ID: 7051893

Claim:
A liquid container comprising: an outer wall forming a casing; an inner wall forming an inner bladder for accommodating liquid, said inner bladder having an outer shape substantially equivalent to an inner shape of said outer wall and being separable from said casing, said inner wall having multiple layers including an elasticity control layer; a pinch-off portion where portions of said inner wall are welded to each other and are pinched by said outer wall to be supported by said outer wall, wherein a part of said inner wall forming said pinch-off portion is exposed to outside of said casing, said inner wall includes a thicker portion having a larger thickness than another portion of said inner wall, at both sides of the welded portion, and the thicker portion is convex toward said inner bladder; and a cavity provided between an outer surface of the thicker portion of said inner wall and an inner surface of a corresponding portion of said outer wall, wherein the cavity exists in the state when liquid is within the inner bladder, and said thicker portion of said inner wall is movable by the cavity, and when the liquid is within the inner bladder, the cavity includes a first gap and a second gap, the first gap being larger than the second gap when the container is subjected to an external impact and thereby providing a dampening effect.