Patent ID: 7212778

Claim:
A cleaning apparatus for an image forming apparatus, comprising: a cleaned member; and a cleaning blade coming into contact with a surface of the cleaned member thereby scraping off a toner, said cleaning blade including an elastic material having an anisotropy in tensile stress; wherein a breaking elongation L (%) of the cleaning blade in a portion close to the abutment portion satisfies: L/ 100>(μ N/M )×(sin 2 θ/E 1+cos 2 θ/E 2) wherein N (N/in) is an abutment pressure of said cleaning blade per unit longitudinal length at an abutment part in which said cleaning blade abuts against said cleaned member; θ (degrees) is an abutment angle between a tangential line of the cleaned member and the cleaning blade at the abutment part in a downstream direction to which said cleaned member moves; E1 (N/m 2 ) is a tensile stress at 5% elongation in a direction of thickness of the elastic material; E2 (N/m 2 ) is a tensile stress at 5% elongation in a direction of a plane substantially perpendicular to the direction of the thickness of the elastic material; M (m) is a contact length between said cleaning blade and said cleaned member in a direction to which said cleaning blade moves and μ is a friction coefficient between the cleaning blade and the cleaned member under a condition wherein said cleaning blade abuts against said cleaning blade by the abutment pressure per unit longitudinal length N(N/m) with the abutment angle θ (degrees).