Vessel for easily polymerizable compound

A vessel for an easily polymerizable compound, receiving a liquid containing an easily polyrnerizable compound, comprising:

• a receiving part, which has a side wall and a supply port opened to the side wall for supplying the liquid, for receiving the liquid supplied from the supply port;
• a top plate, which is provided so as to extend from the side wall above the supply port, for preventing upward scattering of the liquid from the supply port;
• an impingement plate, which is provided away from the supply port, for preventing scattering of the liquid from the supply port to a supply direction;
• a liquid circulation passage for drawing the liquid received in the receiving part and for returning the liquid to the receiving part through the supply port;
• and
• a reboiler for heating the liquid in the liquid circulation passage;
• wherein
• a top face of the top plate is inclined downward from a base end to a tip end of the top plate, when a side wall end of the top plate is defined as the base end and an extended end of the top plate is defined as the tip end, and an angle between the top face of the top plate and the side wall is in a range of 91 to 135°.