Liquid Developer and Image Forming Apparatus

A liquid developer which comprises an insulation liquid containing a fatty acid monoester and toner particles comprised of a resin material, and the resin material containing a component of which molecular weight M is 10,000 or less,

• wherein in the case where a part of the toner particles is taken out from the liquid developer, a weight-average molecular weight Mw of the resin material and an amount of the component are obtained by the following steps, the steps comprising:
• subjecting the resin material contained in the part of the toner particles to a size exclusion chromatography to obtain a chromatogram and an integral distribution curve of the molecular weight of the resin material, the chromatogram having at least one peak, and the integral distribution curve plotted using a graph in which the ordinate axis represents a relative amount (%) of the resin material with respect to the total amount of the resin material (100%) and the abscissa axis represents the weight-average molecular weight Mw (log) of the resin material;
• analyzing the at least one peak of the obtained chromatogram to obtain a first result which shows that the at least one peak is a peak corresponding to the resin material of which weight-average molecular weight Mw is in the range of 19,000 to 195,000;
• and
• analyzing the obtained integral distribution curve to obtain a second result which shows that the amount of the component contained in the resin material is in the range of 5 to 40 wt %.

An image forming apparatus, comprising:

• a plurality of developing sections for forming a plurality of monochromatic color images using a plurality of liquid developers of different colors;
• an intermediate transfer section to which the plurality of monochromatic color images formed by the developing sections are sequentially transferred to form an intermediate transfer image which is formed by overlaying the transferred monochromatic color images one after another;
• a secondary transfer section for transferring the intermediate transfer image onto a recording medium to form an unfixed image onto the recording medium;
• and
• a fixing device for fixing the unfixed image onto the recording medium;
• wherein each of the plurality of liquid developers of different colors comprises an insulation liquid containing a fatty acid monoester and toner particles comprised of a resin material, and the resin material containing a component of which molecular weight M is 10,000 or less, wherein a weight-average molecular weight Mw of the resin material is in the range of 20,000 to 200,000 and an amount of the component contained in the resin material is in the range of 5 to 40 wt %.