Electrostatic latent image developing toner, its production method, developer, image-forming device and image-forming method
View Patent ↗An electrostatic latent image developing dry toner and the like are provided, in which toner remaining after transfer can be recovered during developing with or without having a blade cleaning stage for promoting friction of an electrostatic latent image holding member. The electrostatic latent image developing toner contains toner particles containing a binder resin and a colorant and monodisperse resin particles having a volume mean diameter of 80 to 300 nm, a gel ratio of 60% or more by weight, and a standard deviation of D50×0.20 or less. A method of producing the above toner first mixes monodisperse resin particles, which have a volume mean diameter of 80 to 300 nm, a gel ratio of 60% or more by weight, and a standard deviation of D50×0.20 or less, with toner particles containing a binder resin and a colorant, and adds an inorganic compound having a diameter smaller than that of the resin particles with a shear lower than the first mixing.
1. An electrostatic latent image developing toner, comprising:
toner particles containing a binder resin and a colorant, and
resin particles having a volume mean diameter of 80 to 300 nm, a gel ratio of 60% or greater by weight, and a negative charged polarity with standard deviation of D50×0.20 or less, wherein:
the gel ratio=(weight of resin particles not dissolved into organic solvent/weight of resin particles used as sample)×100.
2. The electrostatic latent image developing toner according to claim 1 , wherein:
the electrostatic latent image developing toner is a toner having a shape with a shape factor SF1 of 100 to 140, and
the shape factor SF1 =ML 2 /A ×100π/4
(where, ML: absolute maximum length of toner particles, A: projected area of toner particles).
3. The electrostatic latent image developing toner according to claim 1 , wherein the resin particles and the electrostatic latent image developing toner have the same charged polarity with respect to a charging member.
4. The electrostatic latent image developing toner according to claim 1 , wherein the resin particles have a gel ratio of 80% or greater by weight.
5. The electrostatic latent image developing toner according to claim 1 , wherein an inorganic compound having a size smaller than that of the resin particles and a volume mean diameter of 80 nm or less.
6. The electrostatic latent image developing toner according to claim 1 , an added amount of the resin particles is in the range of 0.5 to 5 parts by weight to 100 parts by weight of the toner.
7. A two-component developer comprising a carrier and a toner, wherein the toner is the toner of claim 1 .
8. The two-component developer according to claim 7 , wherein the resin particles and the electrostatic latent image developing toner have the same charged polarity with respect to the carrier.
9. The two-component developer according to claim 7 , wherein the carrier is a resin-coated carrier having a resin-coated layer containing a conductive material dispersed into a matrix resin, on a core material.
10. A method of producing an electrostatic latent image developing toner, comprising mixing resin particles having a volume mean diameter of 80 to 300 nm, a gel ratio of 60% by weight or more, and a standard deviation of D50×0.20 or less with toner particles containing a binder resin and a colorant, and adding to mix an inorganic compound having a size smaller than that of the resin particles with a share smaller than that of the previous mixing.
11. The method of producing an electrostatic latent image developing toner according to claim 10 , wherein a volume average size of the inorganic compound having a size smaller than that of the resin particles is 80 nm or less.
12. The method of producing an electrostatic latent image developing toner according to claim 10 , wherein an added amount of the resin particles is 0.5 to 5 parts by weight of the resin particles to 100 parts by weight of the toner.
13. An image-forming device, comprising a latent image holding member, charging means for charging the surface of the latent image holding member, latent image-forming means for forming an electrostatic latent image on the surface of the charged latent image holding member, developing means for developing the electrostatic latent image with a toner, and transfer means for transferring the toner image formed by developing onto a recording medium, wherein:
the toner is a toner containing toner particles consisting of a binder resin and a colorant, and resin particles having a volume mean diameter of 80 to 300 nm, a gel ratio of 60% by weight or more, and a standard deviation of D50×0.20 or less.
14. The image-forming device according to claim 13 , wherein:
the toner consists of a cyan toner, a magenta toner, and a yellow toner respectively containing cyan, magenta, and yellow colorants, and
the transfer means comprises means which temporarily transfer to superpose the respective color toner images formed by developing with the plurality of toners onto the transfer material and transferring the superposed color toner images onto the surface of the recording medium at one time.
15. The image-forming device according to claim 13 , further comprising:
cleaning means for removing toner remaining on the latent image holding member after the transfer, wherein:
the cleaning means are means for recovering toner remaining on the latent image holding member using an electrostatic brush.
16. The image-forming device according to claim 13 , further comprising recovering means which recover toner remaining on the latent image holding member into a developing unit without rubbing the latent image holding member by a blade.
17. An image-forming method, comprising a charge stage for charging the surface of a latent image holding member, a latent image processing stage for forming an electrostatic latent image on the surface of the charged latent image holding member, a developing stage for developing the electrostatic latent image with a toner, and a transfer stage for transferring the toner image formed by developing onto a recording medium, wherein:
the toner is a toner containing toner particles consisting of a binder resin and a colorant and resin particles having a volume mean diameter of 80 to 300 nm, a gel ratio of 60% by weight or more, and a standard deviation of D50×0.20 or less.
18. The image-forming method according to claim 17 , wherein:
the toner consists of a cyan toner, a magenta toner, and a yellow toner respectively containing cyan, magenta and yellow colorants, and
the transfer stage has a stage of temporarily transferring to superpose the respective color toner images, which are formed by developing with the plurality of toners, on a transfer material and transferring the superposed color toner images onto the surface of a recording medium at one time.
19. The image-forming method according to claim 17 , further comprising a cleaning stage for removing toner remaining on the latent image holding member after the transfer, wherein:
the cleaning stage is a stage for recovering toner remaining on the latent image holding member by an electrostatic brush.
20. The image-forming method according to claim 17 , further comprising a recovery stage for recovering the toner remaining on the latent image holding member into the developing unit without rubbing the latent image holding member using a blade.