Image forming apparatus

An image forming apparatus comprising:

• a first image forming unit including a first image bearing member and a first developing unit configured to form a toner image by developing an electrostatic latent image formed on the first image bearing member;
• a second image forming unit including a second image bearing member and a second developing unit configured to form a toner image by developing an electrostatic latent image formed on the second image bearing member;
• an intermediate transfer member on which the toner image formed on the first image bearing member and the toner image formed on the second image bearing member are transferred so as to be overlapped, the toner images transferred to the intermediate transfer member being to be transferred to a printing material;
• and
• a control unit configured to control the first image forming unit and the second image forming unit,
• wherein the first image forming unit further includes a first primary transfer unit configured to transfer the toner image formed on the first image bearing member to the intermediate transfer member, and
• the second image forming unit further includes a second primary transfer unit configured to transfer the toner image formed on the second image bearing member to the intermediate transfer member, and
• wherein the control unit performs control so as to allow execution of a first mode and a second mode in which a color gamut of an image to be formed on a printing material is expanded from the first mode, as an image forming mode for forming an image on a printing material, and
• the second mode includes a second single-color mode in which image formation is performed by only the first image forming unit and a second multicolor mode in which image formation is performed by the first image forming unit and the second image forming unit,
• wherein, in the second single-color mode, the control unit
• i) brings the first developing unit into contact with the first image bearing member and separates the second developing unit from the second image bearing member, and
• ii) brings the first primary transfer unit into contact with the first image bearing member via the intermediate transfer member and separates the second primary transfer unit from the second image bearing member, and
• wherein, in a case where a print job received from an external apparatus satisfies a predetermined condition, in the second single-color mode, the control unit further brings the first and second developing units into contact with the first and second image bearing members, respectively, and brings the first and second primary transfer units into contact with the first and second image bearing members, respectively, via the intermediate transfer member.