Liquid container and liquid ejection apparatus

A liquid container for supplying a liquid to a liquid ejection head, comprising:

• a liquid container part configured to store the liquid;
• a liquid injection part,through which the liquid is injected to the liquid container part from an outside;
• an air introduction part,through which outside air is introduced to the liquid container part and
• a buffer part that is in communication with the liquid container part via a first communication path, and in communication with the air introduction part via a second communication path,
• wherein when the liquid container is in a first orientation in which the liquid is supplied to the liquid ejection head at the time the liquid is to be ejected, a first opening end of the first communication path is located in an area in the liquid container part where air is present when the liquid occupies half the capacity of the liquid container part, the first opening end being an opening end of the liquid container part, and
• the buffer part, when the liquid container is in a second orientation that is rotated from the first orientation by 180°, is configured to store the liquid having a volume that is equal to or larger than a volume of the liquid in the liquid container part such that a surface of the liquid is located below a second opening end and a third opening end, the second opening end being an opening end of the first communication path in the buffer part, and the third opening end being an opening end of the second communication path in the buffer part.