Developer and image forming method

• US 7,855,042 B2
• Filed: 05/30/2007
• Issued: 12/21/2010
• Est. Priority Date: 01/06/2006
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yoshiba, Daisuke, Okado, Kenji, Kobori, Takakuni, Yamazaki, Katsuhisa, Fujimoto, Masami, Moribe, Syuhei
• Primary Examiner(s): LE, HOA VAN
• Application Number:
  US11/755,225
• Publication Number:
  US 20070224530A1
• Time in Patent Office: 1,301 Days
• Field of Search: 430/108.6, 430/108.7
• US Class Current: 430/108.6
• CPC Class Codes: G03G 5/05 Organic bonding materials; Methods for coating a substrate with a photoconductive layer; Inert supplements for use in photoconductive layers
• CPC Class Codes: G03G 5/0525 Coating methods
• CPC Class Codes: G03G 5/0539 Halogenated polymers
• CPC Class Codes: G03G 5/0542 Polyvinylalcohol, polyallylalcohol; Derivatives thereof, e.g. polyvinylesters, polyvinylethers, polyvinylamines
• CPC Class Codes: G03G 5/0564 Polycarbonates
• CPC Class Codes: G03G 5/0596 Macromolecular compounds characterised by their physical properties
• CPC Class Codes: G03G 5/06142 arylamine
• CPC Class Codes: G03G 5/06147 alkenylarylamine
• CPC Class Codes: G03G 5/0696 Phthalocyanines
• CPC Class Codes: G03G 5/147 Cover layers
• CPC Class Codes: G03G 5/14704 comprising inorganic material
• CPC Class Codes: G03G 5/14734 Polymers comprising at least one carboxyl radical, e.g. polyacrylic acid, polycrotonic acid, polymaleic acid; Derivatives thereof, e.g. their esters, salts, anhydrides, nitriles, amides
• CPC Class Codes: G03G 5/14795 Macromolecular compounds characterised by their physical properties
• CPC Class Codes: G03G 9/081 by mixing the toner components in a liquefied state; melt kneading; reactive mixing
• CPC Class Codes: G03G 9/0815 Post-treatment
• CPC Class Codes: G03G 9/0819 characterised by the dimensions of the particles
• CPC Class Codes: G03G 9/0835 Magnetic parameters of the magnetic components
• CPC Class Codes: G03G 9/08711 with esters of acrylic or methacrylic acid
• CPC Class Codes: G03G 9/08755 Polyesters
• CPC Class Codes: G03G 9/08795 characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants
• CPC Class Codes: G03G 9/08797 : characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature
• CPC Class Codes: G03G 9/09708 : Inorganic compounds

Abstract

To provide a developer and an image forming method with each of which a high-resolution, high-definition image can be stably obtained over a long time period irrespective of an environment. The present invention provides a developer including at least: toner particles each containing at least a binder resin; and a composite inorganic fine powder, the developer being characterized in that: the composite inorganic fine powder has a peak at a Bragg angle (2θ±0.20 deg) of each of 32.20 deg, 25.80 deg, and 27.50 deg in a CuKα characteristic X-ray diffraction pattern; and the half width of the X-ray diffraction peak at a Bragg angle (2θ±0.20 deg) of 32.20 deg is 0.20 to 0.30 deg.

Claims

1. A developer, comprising at least:

toner particles each containing at least a binder resin; and

a composite inorganic fine powder,

wherein;

the composite inorganic fine powder is a composite integrally formed from strontium titanate, strontium carbonate and titanium oxide, and has a peak at a Bragg angle (2θ

±

0.20 deg) of 32.20 deg originating from strontium titanate, 25.80 deg originating from strontium carbonate, and 27.50 deg originating from titanium oxide in a CuKα

characteristic X-ray diffraction pattern; and

a half width of the X-ray diffraction peak at a Bragg angle (2θ

±

0.20 deg) of 32.20 deg is 0.20 to 0.30 deg, wherein an intensity level (Ia) of the peak of 32.20 deg, an intensity level (Ib) of the peak of 25.80 deg and an intensity level (Ic) of the peak of 27.50 deg satisfy the following formulae;

0.010<

(Ib)/(Ia)<

0.150 and

0.010<

(Ic)/(Ia)<

0.150.

2. A developer according to claim 1, wherein the composite inorganic fine powder has a number average particle diameter of 30 nm or more to less than 1,000 nm.

3. An image forming method, comprising at least the steps of:

charging an image bearing member;

forming an electrostatic latent image on the image bearing member by exposure;

developing the electrostatic latent image on the image bearing member with a developer to form a developer image;

transferring the developer image onto a transfer material through or without through an intermediate transfer member; and

fixing the transferred developer image to the transfer material,

wherein the developer according to claim 1 is used as the developer.

4. An image forming method according to claim 3, wherein:

the image bearing member has a conductive substance, and a photoconductive layer containing at least amorphous silicon and a surface protective layer on the conductive substance; and

the electrostatic latent image is developed by using the developer according to a reversal development mode.

5. An image forming method according to claim 3, wherein:

the image bearing member has a photosensitive layer on the base body, and has, in its surface, 20 to 1,000 grooves each having a groove width of 0.5 to 40.0 μ

m per 1,000 μ

m in a circumferential direction; and

an average width W (μ

m) of the grooves present in the surface of the image bearing member and a number average particle diameter d (nm) of the composite inorganic fine powder satisfy the following formulae;

30≦

d<

1,000

20.0≦

W/(d×

10<sup>−

3</sup>)≦

500.0.

6. An image forming method according to claim 5, wherein the surface of the image bearing member has a universal hardness value HU (N/mm²) of 150 to 240, and an elastic deformation ratio We (%) of 44 to 65.