Cleaning member and elastic member

A cleaning member comprising an elastic member comprising a polyurethane, and the cleaning member cleans a surface of a to-be-cleaned member through contact of at least a part of the elastic member against the surface of the to-be-cleaned member,

• wherein in measurement with a temperature range of −20° C. to +60° C. of a loss factor tan δ of a sample sampled from the elastic member so as to include a portion of contact with the to-be-cleaned member,
• a peak temperature of a peak denoting a maximum value of tan δ is present at 15.0° C. or below, and a maximum value of tan δ is from 0.20 to 0.55, and
• tan δ at a temperature of 55° C. is 0.13 or larger, and
• wherein, when the sample sampled from the elastic member so as to include the portion of contact with the to-be-cleaned member is heated and vaporized within an ionization chamber and heated up to 1000° C. at a ramp rate of 10° C./second by using a mass spectrometer of direct sample introduction type which ionizes molecules constituting the sample, with M1 denoting a detected amount of all ions obtained, and M2 denoting a peak integrated intensity in an extracted ion thermogram corresponding to a range of an m/z value derived from a polyfunctional isocyanate having three or more isocyanate groups,
• M2/M1 is 0.001 or higher.