Liquid ejection head and cleaning method

A liquid ejection head comprising:

• an ejection port configured to eject a liquid stored in a liquid chamber;
• an electrothermal conversion element configured to eject the liquid from the ejection port by heat generation;
• a first electrode configured to protect the electrothermal conversion element and to be capable of eluting into the liquid by an electrochemical reaction with the liquid;
• a second electrode installed so as to be electrically connectable to the first electrode via the liquid;
• and
• a first circuit,
• wherein a voltage is applied to cause the second electrode to generate the electrochemical reaction with the first electrode so that the first electrode is eluted into the liquid,
• wherein the first circuit is configured to reverse polarities between the first electrode and the second electrode for applying the voltage,
• wherein the first circuit comprises a second circuit including a plurality of first electrodes as a part of wiring, and
• wherein the second circuit comprises a measuring unit configured to measure wiring resistance and wiring resistance in the second circuit can be measured by the measuring unit.

A cleaning method for a liquid ejection head including:

• a first electrode configured to protect an electrothermal conversion element that ejects a liquid in a liquid chamber from an ejection port by heat generation and to be capable of eluting into the liquid by an electrochemical reaction with the liquid;
• a second electrode configured to be capable of eluting into the liquid by an electrochemical reaction with the liquid and installed so as to be electrically connectable to the first electrode via the liquid;
• and
• a first circuit,
• wherein a voltage is applied to cause the second electrode to generate the electrochemical reaction with the first electrode so that the first electrode is eluted into the liquid, and thus kogation originating from the liquid adhering to the first electrode is removed,
• wherein the first circuit is configured to reverse polarities between the first electrode and the second electrode for applying the voltage,
• wherein the first circuit comprises a second circuit including at least one of a plurality of first electrodes and a plurality of second electrodes as a part of wiring, and
• wherein the second circuit comprises a measuring unit configured to measure wiring resistance and wiring resistance in the second circuit can be measured by the measuring unit,
• the cleaning method comprising:
• measuring a resistance value in the second circuit;
• and
• determining whether or not kogation on the first electrode can be removed based on the measured resistance value.