TWO-COMPONENT DEVELOPER AND IMAGE FORMING METHOD

• Main Authors: KAYAMORI TAKANARI, KUBO YUYA
• Format: Patent
• Language: English; Japanese
• Published: 21.12.2022
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

To provide a two-component developer that has near infrared permeability, has high image density, and is excellent in resistance of electrostatic propensity against environmental conditions, and an image forming method.SOLUTION: In a two-component developer of the present invention, a toner base particle contains a coloring agent. The coloring agent contains a pigment P1 and a pigment P2. When the pigments P1 and P2 are each dispersed in methyl ethyl ketone, an absorption maximum wavelength λmax of the pigment P1 is within a range of 400 nm or more and less than 600 nm, and λmax of the pigment P2 is within a range of 600 nm or more and 700 nm or less. An external additive contains titanium oxide. The content of the titanium oxide is 0.01 mass% or more and less than 1.00 mass% based on the total mass of the toner base particle. The content of iron element in a surface of a carrier measured by X-ray photoelectron spectroscopy satisfies a specific formula.SELECTED DRAWING: None 【課題】本発明の課題は、近赤外線の透過性を有し、画像濃度が高く、帯電性の環境条件耐性に優れた二成分現像剤及び画像形成方法を提供することである。【解決手段】本発明の二成分現像剤は、トナー母体粒子が、着色剤を含有し、前記着色剤が、顔料Ｐ１及び顔料Ｐ２を含有し、前記顔料Ｐ１及びＰ２を、それぞれ、メチルエチルケトンに分散させたときの吸収極大波長λｍａｘが、前記顔料Ｐ１については４００ｎｍ以上、６００ｎｍ未満の範囲内であり、前記顔料Ｐ２については６００ｎｍ以上、７００ｎｍ以下の範囲内であり、外添剤が、酸化チタンを含有し、前記酸化チタンの含有量が、トナー母体粒子の総質量に対して、０．０１質量％以上、１．００質量％未満であり、キャリアの表面のＸ線光電子分光法で測定される鉄元素含有率が、特定式を満たすことを特徴とする。【選択図】なし