Electrostatic image developing toner
View Patent ↗Provided is an electrostatic image developing toner containing, (i) toner particles containing: a binder resin having a domain-matrix structure; and (ii) a colorant; wherein the toner particles have a volume-based median diameter of 4.3 to 7.0 μm; a domain phase in the binder resin contains a polymer containing a structure unit derived from a diene monomer, the domain phase has a Feret diameter of 50 to 300 nm; and a glass transition temperature of the polymer composing the domain phase is −85 to +35° C.
1. An electrostatic image developing toner comprising, toner particles containing:
(i) a binder resin having a domain-matrix structure; and
(ii) a colorant;
wherein the toner particles have a volume-based median diameter of 4.3 to 7.0 μm;
a matrix phase in the binder resin is composed of a polymer of a styrene-acrylic resin or a polyester resin;
a domain phase in the binder resin comprises a polymer containing a structure unit derived from a diene monomer,
the domain phase has a Feret diameter of 50 to 300 nm; and
a glass transition temperature of the polymer composing the domain phase is −85 to +35° C.
2. The electrostatic image developing toner of claim 1 ,
wherein the polymer composing the domain phase contains a structure unit derived from an acidic monomer.
3. The electrostatic image developing toner of claim 2 ,
wherein the acidic monomer contains a carboxylic group.
4. The electrostatic image developing toner of claim 2 ,
wherein the acidic monomer forms a copolymer and a content of the acidic monomer in the copolymer is 1 to 5 mass %.
5. The electrostatic image developing toner of claim 1 ,
wherein the polymer composed of the domain phase is a styrene-butadiene rubber, and a copolymerization ratio of styrene to butadiene is between 30:70 and 50:50.
6. The electrostatic image developing toner of claim 1 ,
wherein the domain phase has a Feret diameter of 75 to 250 nm.
7. The electrostatic image developing toner of claim 1 ,
wherein a variation coefficient of a particle size distribution in the Ferret diameter of domain phases is 20% or less.
8. The electrostatic image developing toner of claim 1 ,
wherein a content ratio of toluene insoluble components contained in the polymer composing the domain phase is from 15 to 95 mass %.
9. The electrostatic image developing toner of claim 1 ,
wherein a content ratio of toluene insoluble components contained in the polymer composing the domain phase is from 30 to 70 mass %.
10. The electrostatic image developing toner of claim 1 ,
wherein toluene insoluble components contained in the polymer composing the domain phase has a mass average molecular weight (Mw) of 20,000 to 1,500,000.
11. The electrostatic image developing toner of claim 1 ,
wherein toluene insoluble components contained in the polymer composing the domain phase has a mass average molecular weight (Mw) of 40,000 to 800,000.
12. The electrostatic image developing toner of claim 1 ,
wherein a content of the polymer composing the domain phase is 0.3 to 7.0 mass % based on a total mass of the polymer composing the matrix phase and the polymer composing the domain phase.
13. The electrostatic image developing toner of claim 1 ,
wherein a content of the polymer composing the domain phase is 2.5 to 4.0 mass % based on a total mass of the polymer composing the matrix phase and the polymer composing the domain phase.
14. The electrostatic image developing toner of claim 1 ,
wherein the styrene-acrylic resin is a random copolymer made of a styrene system monomer and an acrylic acid system monomer.
15. The electrostatic image developing toner of claim 1 ,
wherein the glass transition temperature of the polymer composing the domain phase is −45 to +30° C.