Toner for forming electrostatic image, developer, process cartridge, and image forming apparatus
To provide a toner, which contains a colorant, a binder resin, and a releasing agent, wherein the toner satisfies the following (a) to (c): (a) the toner contains at least a polyester resin as the binder resin; (b) the toner has Tg1st of 25° C. to 50° C.; and (c) the toner has a TMA compressive deformation rate (TMA %) of 10% or lower at 50° C. under a condition having relative humidity of 70%, wherein the Tg1st is glass transition temperature of the toner for first heating, as the toner is measured by a DSC system (a differential scanning calorimeter).
1. A toner, comprising:
a colorant;
a binder resin; and
a releasing agent,
wherein the toner satisfies the following (a) to (c):
(a) the toner contains at least a polyester resin as the binder resin;
(b) the toner has Tg1st of 25° C. to 50° C.; and
(c) the toner has a TMA compressive deformation rate (TMA %) of 10% or lower at 50° C. under a condition having relative humidity of 70%,
wherein the Tg1st is glass transition temperature of the toner for first heating, as the toner is measured by a DSC system (a differential scanning calorimeter), and
wherein a tetrahydrofuran (THF) insoluble component of the toner has Tg2nd′ of −40° C. to 30° C. as measured by differential scanning calorimeter (DSC), and the THF insoluble component has storage elastic modulus G′ of 10 6 to 10 8 at 40° C., and a storage elastic modulus G′ of 10 5 to 10 7 at 100° C.,
wherein the polyester resin contains a plurality of polyester resins, and at least one of the polyester resins is a non-crystalline polyester resin containing a diol component as a constitutional component, where the diol component contains C3-C10 aliphatic diol in an amount of 50 mol % or greater, and trivalent or higher acid or trihydric or higher alcohol as a crosslink component, and
wherein a number of carbon atoms in a principle chain of the diol component is an odd number, and the diol component has an alkyl group at a side chain thereof.
2. The toner according to claim 1 , wherein the Tg1st of the toner—Tg2nd of the toner is 10° C. or greater, where the Tg2nd is glass transition temperature of the toner for second heating, as the toner is measured by a DSC system (differential scanning calorimeter).
3. The toner according to claim 1 , wherein the crosslink component is trivalent acid or trihydric alcohol.
4. The toner according to claim 1 , wherein the polyester resin is composed of said non-crystalline polyester resin and a crystalline polyester resin B.
5. The toner according to claim 4 , wherein a crystalline polyester resin B content is 3% by mass to 20% by mass.
6. The toner according to claim 4 , wherein the crystalline polyester resin B has a crosslink structure formed from unsaturated double bond segments.
7. The toner according to claim 4 , wherein the crystalline polyester resin B has a melting point of 60° C. to 80° C., and the polyester resin B contains a C4-C12 linear saturated aliphatic dicarboxylic acid in an amount of 80 mol % or greater relative to a total acid component, and C2-C12 linear saturated aliphatic diol in an amount of 80 mol % or greater relative to a total alcohol component.
8. A developer, comprising:
a toner; and
a carrier,
wherein the toner is the toner according to claim 1 .
9. The toner according to claim 1 , wherein:
the polyester resin is composed of said non-crystalline polyester resin and a crystalline polyester resin B; and
the crystalline polyester resin B has a melting point of 60° C. to 80° C., and the polyester resin B contains a C4-C12 linear saturated aliphatic dicarboxylic acid in an amount of 80 mol % or greater relative to a total acid component, and C2-C12 linear saturated aliphatic diol in an amount of 80 mol % or greater relative to a total alcohol component.