Electrophotographic photoreceptor, image forming apparatus, and coating liquid for forming photosensitive layer

An electrophotographic photoreceptor which is a positive charging type electrophotographic photoreceptor comprising a conductive support and a single-layer type photosensitive layer on the conductive support, wherein

• the single-layer type photosensitive layer comprises a charge generating material, a hole transport material, an electron transport material, and a binder resin in the same layer, and
• the single-layer type photosensitive layer comprises a filler, a polyvinyl acetal resin, and oxytitanium phthalocyanine as the charge generating material, which has a main clear peak at a Bragg angle 2θ±0.2° of 27.2° in powder X-ray diffraction using a CuKα characteristic X-ray.

A coating liquid, which comprises a binder resin, a charge generating material, a hole transport material, an electron transport material and a solvent, and comprises oxytitanium phthalocyanine which has a strong diffraction peak at a Bragg angle (2θ±0.2) of 27.2° in X-ray diffraction by a CuKα ray, as the charge generating material, wherein

• when the coating liquid is stored under conditions of a temperature of 55° C. and relative humidity of 10%, for 96 hours, a changing rate of a half decay amount E1/2 in the photoreceptor is equal to or less than 75%.