Shin Araki

Glass transition temperature of copolymers used as printer toner

The thermal characteristics of copolymers commonly used as toner in the electrophotographic process are critical- and in particular their glass transition temperature. We used emulsion polymerization to synthesize two kinds of copolymer toner with various molecular weights, styrene-n-butyl methacrylate and n-bythyl acrylate, and evaluated their glass transition temperatures using differential scanning calorimetry. The glass transition temperature of copolymers was determined not by their average molecular weight, but by their mole fractions.

Adsorption and Oxidation Species on a-SiC:H Surface by Corona Exposure

The hydrogenated amorphous silicon (a-Si:H) photoreceptor used in printing systems produces image blurring at high temperature and humidity. We have examined the problem using infrared reflective-absorption spectroscopy (IR-RAS). We exposed a hydrogenated amorphous silicon carbide (a-SiC:H) film to a corona discharge at 35°C and 80% RH. Adsorption and oxidation species on the film can be detected and determined by IR-RAS. NO3-, CO32-, Si-OH, H-OH, and Si-O-Si are detectable in the a-SiC:H film. The amount of them increases with corona exposure time. We clarify that these specids in a-SiC:H film cause the contact angles to decrease with the corona exposure time and blur the image.