Electrostatic latent image developer, image forming method, and image forming apparatus

A method for forming an image, comprising:

• a latent image processing stage for forming an electrostatic latent image on an electrostatic latent image holding member;
• a developing stage for developing the electrostatic latent image using a developer;
• a transfer stage for transferring a toner image formed through the development onto a transfer material;
• and
• a fixation stage for fixing the toner image on the transfer material, wherein
• the developer is an electrophotographic developer comprising:
• a toner having a shape factor of 140 or less and a volume average particle size distribution GSDv of 1.3 or less;
• and
• an electrophotographic carrier having a coat resin layer on a core material, the coat resin layer containing a conductive powder, the core material having a dynamic electric resistivity of 1 Ω·cm or less under an electric field of 104 V/cm in a form of a magnetic brush, the conductive powder having an electric resistivity of 101 Ω·cm or greater and 106 Ω·cm or less, and the carrier having an electric resistivity in a range between 10 and 1×108 Ω·cm, wherein
• the shape factor is defined by an equation,
• Shape Factor=(ML2/A)×(π/4)×100
• wherein ML represents the absolute maximum length of the toner and A represents the projected area of the toner, and
• the volume average particle size distribution GSDv is defined by an equation,
• GSDv=(D84/D16)1/2
• wherein volume D16 represents a particle size where an accumulated volume in an accumulation distribution from smaller size reaches 16% and volume D84 represents a particle size where the accumulated volume in the accumulation distribution reaches 84%, wherein
• in the latent image processing stage, when an exposing means applies an image exposure process corresponding to an image signal to form an electrostatic latent image, the image signal to be output to the exposing means is processed so that the output image signal is produced by comparing the input image signal and a threshold value matrix to which threshold values are stored in advance for determining whether or not each pixel within a screen cell comprising a plurality of pixels in a dot-concentrated type screen is to be recorded, wherein
• the threshold value matrix is a threshold value matrix in which, when a non-linear region is present in a part of the image signal-output density characteristic, linearity is improved by inserting, between threshold values of the non-linear region in the image signal-output density characteristic where the slope is large, non-recording isolated pixels which are a pixel before and a pixel after in the main scan direction of the target pixel to be switched on, the non-recoding isolated pixels being switched off, and wherein
• the peripheral speed of the electrostatic latent image holding member is 200 mm/sec or greater.