Toner

A toner, comprising:

• a toner particle comprising a binder resin and a colorant;
• and
• an external additive comprising an external additive A;
• external additive A being inorganic line particles or organic-inorganic composite tine particles having a Feret diameter of 60 to 200 nm;
• and
• an adhesion index of external additive A to the toner being 0.00 to 3.00, wherein
• 60≤b÷c≤200 and 0.15≤b/(b+c)≤0.30, where b (nm) denotes a penetration depth of external additive A at a portion of external additive A penetrating into the interior of the toner particle from the surface of the toner particle, and c (nm) denotes a protrusion height of external additive A at that portion in an observation of an image resulting from image processing of a cross section of the toner using a transmission electron microscope,
• where with an outline X defined as the outline of a portion of contact of external additive A with the toner particle, in the outline of external additive A, and a line segment Z defined as the line segment obtained by joining both ends of the outline X with a straight line, in the observation of the image resulting from image processing of the cross section, penetration depth b denotes a maximum distance bets een the line segment Z and an intersection of the outline X and a perpendicular line from he line segs segment Z to the outline X;
• and with an outline Y defined as the outline of a portion other than the outline X in the outline of the external additive A, in the observation of the image resulting from image processing of the cross section, protrusion height c denotes a maximum distance between the line segment Z and an intersection of the outline Y and a perpendicular line from the line segment Z to the outline Y, and
• in a measurement of the strength of the toner in accordance with a nanoindentation method, a load F at a maximum value is 0.8 to 2.0 mN in a load region from 0.20 to 2.30 mN of a differential curve obtained through differentiating, by load, of a load-displacement curve ith load (mN) on the horizontal axis and displacement amount (μ) on the vertical axis.

A toner, comprising:

• a toner particle comprising a binder resin and a colorant;
• and
• an external additive comprising an external additive A;
• external additive A being inorganic fine particles or organic-inorganic composite tine particles having a Feret diameter of 60 to 200 nm;
• and
• an adhesion index of external additive A to the toner being 0.00 to 3.00, wherein
• 60≤b+c≤200 and 0.15≤b/(b+c)≤0.30, where b (nm) denotes a penetration depth of external additive A at a portion. of external additive A penetrating into the interior of the toner particle from the surface of the toner particle, and c (nm) denotes a protrusion height of external additive A at that portion in an observation of an image resulting from image processing of a cross section of the toner using a transmission electron microscope,
• where with an outline X defined as the outline of a portion of contact of external additive A with the toner particle, in the outline of external additive A, and a line segment Z defined as the line segment obtained by joining both ends of the outline X with a straight line, in the observation of the image resulting from image processing of the cross section, penetration depth b denotes a maximum distance between the line segment Z and an intersection of the outline X and a perpendicular line from the line segment Z to the outline X;
• and with an outline Y defined as the outline of a portion other than the outline X in the outline of the external additive A, in the observation of the image resulting from image processing of the cross section, protrusion height c denotes a maximum distance between the line segment Z and an intersection of the outline Y and a perpendicular line from the line segment Z to the outline Y, and
• l/(b+c) is 0.70 to 0.92, where l (nm) is the length of line segment Z.