Toner
A toner comprises a toner particle and silica fine particles, wherein, fragment ions of a D unit structure are observed in time-of-flight secondary ion mass spectrometry measurement of the silica fine particles, in a titration operation of the silica fine particles using NaOH, the titer is within a specific range, an area of a peak from −25 to −15 ppm in 29 Si-NMR measurement of the silica fine particles is denoted by D, the sum of the areas of peaks from −140 to 100 ppm is denoted by S, and an area of a peak from more than −19 ppm to −17 ppm or less is denoted by D1, the specific surface area of the silica fine particles, D, D1, and S satisfy specific relationships, and a specific amount of a specific polyvalent metal element is present on the surface of the toner particle.
1 . A toner, comprising:
a toner particle;
a silica fine particle on a surface of the toner particle; and
at least one polyvalent metal element selected from the group consisting of calcium, magnesium, aluminum and iron on the surface of the toner particle, wherein
fragment ions corresponding to a structure represented by formula (1) are observed in a time-of-flight secondary ion mass spectrometry measurement of the silica fine particle,
when n represents an integer of 1 or more,
Sn={(a−b)×c×NA}/(d×e) and 0.05≤Sn≤0.20 where 2.00 g of the silica fine particle is dispersed in a mixed liquid of 25.0 g of ethanol and 75.0 g of a 20% by mass NaCl aqueous solution and titration is performed using sodium hydroxide, when a is a NaOH titer (L) required to adjust the mixed liquid in which the silica fine particle is dispersed to pH 9.0, b is a NaOH titer (L) required to adjust the mixed liquid of 25.0 g of ethanol and 75.0 g of a 20% by mass NaCl aqueous solution to pH 9.0, c is the concentration (mol/L) of the NaOH solution used for titration, NA is Avogadro's number, d is the mass (g) of the silica fine particle, and e is a BET specific surface area (nm 2 /g) of the silica fine particle,
where in a chemical shift obtained by a solid-state 29 Si-NMR DD/MAS method of the silica fine particle (D/S)/B is 5.7×10 −4 to 4.9×10 −3 , (D/S)/B measured after washing the silica fine particle with chloroform is 1.7×10 −4 to 4.9×10 −3 and (D1/D) is 0.10 to 0.30, when D is an area of a peak having a peak top present in a range from −25 to −15 ppm, S is the sum of the peak areas of an M unit, a D unit, a T unit, and a Q unit present in a range from −140 to 100 ppm specific surface area of the silica fine particle, and D1 is an area of a peak having a peak top present in a range from more than −19 to −17 ppm or less in the chemical shift, and
a total content of the polyvalent metal element is 1 to 2000 ppm measured by (a) to (c)
(a) stirring 50.0 mg of the toner particles with 5.00 g of 6.0 mol/L nitric acid aqueous solution to obtain an extract,
(b) filtering the extract to prepare a measurement sample, and
(c) measuring the measurement sample using an inductively coupled plasma mass spectrometer to determine a content of the polyvalent metal element based on the mass of the measurement sample.
2 . The toner according to claim 1 , wherein when measured by (a) to (c), the polyvalent metal element comprises 1 to 200 ppm by mass calcium, 2 to 400 ppm by mass magnesium, 5 to 1000 ppm by mass aluminum, and 10 to 2000 ppm by mass iron.
3 . The toner according to claim 1 , wherein a primary particle of the silica fine particle has a number-average particle diameter of 5 to 50 nm.
4 . The toner according to claim 1 , wherein Ssi is 30 to 90% by area when Ssi (area %) is a coverage ratio of the surface of the toner particle by the silica fine particle calculated from an image of the toner surface observed by a scanning electron microscope.
5 . The toner according to claim 1 , wherein the silica fine particle is surface-treated with a compound represented by formula (3)
when R 1 and R 2 are independently a carbinol group, a hydroxy group, an epoxy group, a carboxy group, an alkyl group or a hydrogen atom, m is the average number of repeating units and is an integer of 1 to 200.
6 . The toner according to claim 1 , wherein the silica fine particle has a carbon amount immobilization rate of 30 to 70% after washing with chloroform.
7 . The toner according to claim 1 , wherein the silica fine particle was treated with cyclic siloxane and then treated with silicone oil.
8 . The toner according to claim 1 , wherein the silica fine particle comprises a silica fine particle A and a silica fine particle B,
silica fine particle A has a primary particle with number-average particle diameter of 5 to 25 nm,
silica fine particle B has a primary particle with a number-average particle diameter of more than 25 nm and 70 nm or less, and
silica fine particle A and silica fine particle B are present at a mass-based content ratio of 20:1 to 5:1.