Toner
A toner comprising a toner particle comprising a binder resin and an ester compound, wherein: the binder resin comprises a resin A comprising a specific amount of a long-chain acrylate unit and a styrene-based monomer unit, and a resin B comprising a specific monomer unit in a specific amount; the ester compound has an alkyl chain with a specific chain length, a content of the resin A in the chloroform-soluble portion of the toner particles is 60% by mass or more; and using SPm (J/cm 3 ) 1/2 for a SP value of the long-chain acrylate unit and using SPw (J/cm 3 ) 1/2 for a SP value of the ester compound, SPm is 18.00 to 19.00, and SPm and SPw satisfy formula (a). |SPm−SPw|≤1.50 (a)
1 . A toner, comprising:
a toner particle comprising a binder resin and an ester compound;
the binder resin comprising a resin A and a resin B;
resin A comprising at least one member selected from the group consisting of a sulfide group and disulfide group, and comprising monomer units represented by formulae (1) and (2)
where R 1 represents a hydrogen atom or methyl group, R 2 represents a straight-chain alkyl group having 12 carbon atoms, and R 21 represents a hydrogen atom or methyl group;
resin B comprising monomer units represented by formulae (3) and (4)
where R 31 represents a hydrogen atom or methyl group, R 32 represents an optionally halogen-substituted straight-chain or branched C 1-3 alkylene group, R 33 to R 35 independently represent a benzyl group, phenethyl group, or straight-chain, branched or cyclic C 1-6 alkyl group, X represents a counteranion, and R 22 represents a hydrogen atom or methyl group;
the ester compound being at least one compound selected from the group consisting of compounds represented by formulae (5), (6) and (7)
where R 36 and R 41 independently represent alkylene groups having 2 to 8 carbon atoms, and R 37 , R 38 , R 42 , R 43 , R 51 and R 52 independently represent a straight-chain alkyl group having 14 to 24 carbon atoms, wherein
the toner has an average circularity of 0.97 to 0.99,
a content of the resin A in a chloroform-soluble matter of the toner particle is at least 60 mass %,
a content of the monomer unit represented by formula (1) in resin A is 2.0 to 15.0 mass %,
a content of the monomer unit represented by formula (2) in resin A is at least 48.0 mass %,
a content of the monomer unit represented by formula (4) in resin B is at least 48.0 mass %,
SPm is 18.00 to 19.00, and
|SPm−SPw|≤1.50
when SPm (J/cm 3 ) 1/2 is an SP value of the monomer unit represented by formula (1) and SPw (J/cm 3 ) 1/2 is an SP value of the ester compound, and
an average number of domains of the ester compound present in a toner cross section observed using a scanning transmission electron microscope is at least 250, and r1 is not greater than 1.00 μm when r1 (μm) is an average long diameter of the domains.
2 . The toner according to claim 1 , wherein the monomer unit represented by formula (1) is 3.0 to 15.0 mass % of resin A.
3 . The toner according to claim 1 , wherein resin A comprises a monomer unit represented by formula (8)
4 . The toner according to claim 1 , wherein a loss elastic modulus G″ of the toner at 100° C. is not more than 3.0×10 5 (dyn/cm 2 ) in dynamic viscoelastic measurement of the toner.
5 . The toner according to claim 1 , which has a surface quantity index of 0.2 to 5.0 atomic % measured using x-ray photoelectron spectroscopic analysis, which is an amount of N relative to a total amount of C, N, O and Si.
6 . The toner according to claim 1 , wherein a content of the monomer unit represented by formula (3) in resin A is less than 1.0 mass %, and
a content of the monomer unit represented by formula (1) in resin B is less than 1.0 mass %.
7 . The toner according to claim 1 , wherein the toner particle is a core-shell type toner particle having a core particle comprising the binder resin and having a shell on a surface of the core particle,
the shell comprises a polymer of an alkyl (meth)acrylate ester, and
the alkyl (meth)acrylate ester is at least one member selected from the group consisting of alkyl (meth)acrylate esters having an alkyl group having 1 to 4 carbon atoms.
8 . The toner according to claim 1 , wherein r1 is not greater than 0.10 μm.