Toner, toner production method, and two-component developer
A toner comprising a toner particle and a silica fine particle A on a surface of the toner particle, wherein: a weight-average particle diameter of the toner is 4.0 to 15.0 μm; the silica fine particle A comprises a silicone oil and a carbon loss ratio when the silica fine particle A is washed with hexane is 5 to 70%; and an area of each peak obtained in a solid-state CP/MAS 29 Si-NMR measurement of the silica fine particle A and of the silica fine particle A after washing thereof with hexane is in a specific range.
1 . A toner, comprising:
a toner particle; and
a silica fine particle A on a surface of the toner particle, silica fine particle A comprises a silicone oil;
a weight-average particle diameter of the toner being 4.0 to 15.0 μm, wherein
a carbon loss ratio when silica fine particle A is washed with hexane is 5 to 70%,
SD2/SD1 is 0.05 to 0.30 and
SD2w/SD1w is 0.05 or more
when upon measuring in a solid-state CP/MAS 29 Si-NMR measurement of the silica fine particle A, peak PD1 corresponds to a silicon atom indicated by Si a in Formula (1), peak PD2 corresponds to a silicon atom indicated by Si b in Formula (2), SD1 is an area of peak PD1, and SD2 is an area of peak PD2
where each R independently represents a hydrogen atom, methyl group or ethyl group, and
upon measuring in a solid-state CP/MAS 29 Si-NMR measurement of the silica fine particle A after washing thereof with hexane, peak PD1w corresponds to a silicon atom indicated by Si a in Formula (1), peak PD2w corresponds to a silicon atom indicated by Si b in Formula (2), SD1w is an area of peak PD1w and SD2w be an area of peak PD2w.
2 . The toner according to claim 1 , wherein the carbon loss ratio when the silica fine particle A is washed with hexane is 30 to 55%.
3 . The toner according to claim 1 , wherein silicone oil is released when the silica fine particle A is washed with hexane comprises silicone oil.
4 . The toner according to claim 1 , wherein an amount of a released component on a carbon basis for the silica fine particle A is 3.0 to 9.0 parts by mass relative to 100 parts by mass of the silica fine particle A.
5 . The toner according to claim 1 , wherein silica fine particle A has a BET specific surface area of 70 to 160 m 2 /g.
6 . The toner according to claim 1 , wherein silica fine particle A has a moisture adsorption of 0.01 to 0.07 cm 3 /m 2 per 1 m 2 of a BET specific surface area at a temperature of 30° C. and a relative humidity of 80%.
7 . The toner according to claim 1 , which further comprises silica fine particle B that is different from silica fine particle A.
8 . The toner according to claim 1 , wherein a content of silica fine particle A is 0.20 to 3.00 parts by mass relative to 100 parts by mass of the toner particle.
9 . The toner according to claim 1 , wherein silica fine particle A is a treated material provided by treating silica fine particle with a cyclic siloxane, and further treating a resultant with a silicone oil.
10 . A two-component developer, comprising:
a toner according to claim 1 and a magnetic carrier;
the magnetic carrier comprising a magnetic carrier core particle having a resin-coating layer on a surface of the magnetic carrier core particle;
the resin in the resin-coating layer contains a monomer unit provided by a (meth)acrylate ester having an alicyclic hydrocarbon group.
11 . The two-component developer according to claim 10 , wherein the resin in the resin-coating layer comprises a monomer unit provided by a macromonomer according to Formula (B);
where R 6 is H or CH 3 , and A represents a polymer of at least one compound selected from the group consisting of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, styrene, acrylonitrile and methacrylonitrile.
12 . A toner production method providing the toner according to claim 1 , comprising the steps of:
obtaining a surface-treated material by mixing cyclic siloxane with a silica fine particle substrate and carrying out a heat treatment at a temperature of 300° C. or more;
obtaining a silica fine particle A by further treating the surface-treated material with silicone oil; and
obtaining the toner by mixing a toner particle with the silica fine particle A.
13 . The toner production method according to claim 12 , wherein the temperature when the surface-treated material is further treated with silicone oil is 300° C. or more.