Using the decolorable toner system,ghost image, which is the visible trace of the original image on paper

View full abstract

High-molecular-weight amphiphilic copolymers having both hydrophilic side chain of methoxy polyethyleneglycol (MPEG) and hydrophobic side chain of methoxy-polypropyleneglycol (MPPG) or lauryl as a polymeric dispersant employed for disperse dyes in textile-inkjet inks were proposed. Some random and block copolymers synthesized by means of ordinary solution polymerization, were brought to aqueous dispersions of disperse dye and then made them into inkjet ink. Fine dye-particles, which were dispersed using these polymeric dispersants in the aqueous inkjet ink resulted in smooth gushing of the ink via a piezo-type inkjet printer, and brought out a high uptake capability of dye onto untreated polyester fabric when compared to printing with a dispersant-free inkjet ink. In addition,it was revealed that color strength of the untreated polyester fabric printed with the inkjet inks using these dispersants,as represented by K/S values, showed the values close to that of color print via pretreated polyester fabric.

View full abstract

Triphenyl-pararosaniline (TPPR)is a charge-control agent (CCA) of the positive type for toners in the electrophotographic process. Suganami et al. reported that the charge control ability of TPPR is greatly improved if TPPR forms a charge-transfer (CT) complex with CCAs of the negative type, as those of n-propyl gallate (TPPR/PG=1/2), 3,5-di-tert-butylsalicylate zinc complex (TPPR/SZC=1/3) and 3,5-di-tert-butylsalicylate (TPPR/TBS=1/6). On the contrary, we interpret here the enhanced charge-control ability as arising from protonation of TPPR due to phenolic hydroxides of TBS, SZC and PG. The ratio of TPPR to these acids can be explained in terms of their effective acidity weakened significantly by intra-and intermolecular hydrogen bonds in the solid state, as revealed from structure analysis of these acids.

View full abstract

Latent pigment technologies of hydrogen-bonded pigments(pyrrolopyrroles and quinacridones)have been reviewed and their potential problems when applied to imaging and related areas are discussed. The present technology aims at solubilizing hydrogen-bonded pigments by blocking NH…O intermolecular hydrogen bonds through t-butoxycarbonylation of the NH group. Regeneration is then carried out by heat treatment to give “pigment nano particles” characterized by high transparency. However,the crystalline phase of the regenerated pigment is found to be,not always,the same phase as that of the parent pigment. As a result, the color of regenerated pigments is slightly different and the light-and heat-fastness is inferior to that of the parent pigments. In addition,CO₂ evolved during the regeneration process is found to impair the transparency of pigmented layers.

View full abstract

The progress of medical network technology and dry film development have led to an increasing demand for decentralized Digital Film Imager within the field of medicine. This demand has been fulfilled by the “Film Station”, which has high image quality and high speed printing despite its compact size. “Film Station” is able to provide necessary diagnostic images wherever it is required. Our aim is to continue developing products like the “Film Station”, which can contribute at the diagnostic front.

View full abstract

Solution polymerization, which is commonly carried out in industry to yield synthetic resins, was explained about the typical features. The general explanations for solution polymerization were given from the comparison of solution polymerization and other polymerization, polymerizable monomers for solution polymerization, reaction behavior occurred in polymerization, and the structures of yielded polymers.

View full abstract

Emulsion polymerization converts a monomer emulsion to a dispersion of polymer particles with submicron size. We can get desirable polymer particles employing suitable monomer,emulsifier,initiator,and other ingredients under suitable reaction conditions. This article presents the outline of mechanism and kinetics of emulsion polymerization and the strategy for particle design as well as new trends in emulsion polymerization.

View full abstract

Suspension polymerization is the established polymerization method to prepare polymer beads with the size region from micron to thousand micron. In the suspension polymerization method, it is important to investigate how to make the suspension stable and how to control the polymer bead size. In the method for controlling polymer bead size,there are the soft type of technique by adjusting physical properties of liquids concerned and the hard type of technique by investigating the operating conditions as the geometry of reactor and the mixing condition. By suspension polymerization, composite particles with various structures can be prepared.

View full abstract

The drying process is very important for the production of polymerized toner, since the quality of polymerized toner is dependent on the drying process. The dispersion of wet toner and the low drying temperature (less than 60degrees centigrade) are necessary for the drying of polymerized toner. In this paper, the drying technology of polymerized toner was introduced.

View full abstract