Earticle

In screen printing process, printers are stretching screen meshs of an angle of 45deg. This angle need much more screen mesh’s quantity of 15% than 22.5deg. To search mesh angles have affect on reproducting fine line pattern, we modeled the expecting image according on screen angles change and reconfirmed it’s useful and valid from experimentation.

As inverstigating the influence of monomers and photoinitiator in the polymerization rate of photopolymerization by using IR spectroscopy, photopolymerizations initiated by ultraviolet radiation are characterized by the presence of an autoacceleration in the polymerization rate as the reaction proceeds. The conversion for the end of the autoacceleration varies considerably depending on the monomer and reaction condition which determines coil size and viscosity. In UV curable systems, the autoacceleration begins at only a few percent conversion and continues to 40% in HEA solution and 60% conversion in EHA solution. The polymerization ate in HEA solution increased as follow; DMHA > HCPK > DMPA and could be explained by the interaction between the initiating radical and HEA monomer and the size of the photodissociated radical of initiator. But the tendency of autoacceleration in EHA solution is almost independent on initiator.

For the vehicle of UV ink formulated with prepolymer, reactive diluent and photoinitiator, we measured viscoelasticity of film cured by UV irradiation, investigated dynamic characteristics and structural changes. As a results, it was found that equilibrium modulus and glass transition temperature are ascended, and relaxation modulus master curves are shifted toward the long time region on the curves by the increasingly exposure time. And then, it was found that flexibility tends to superiority but resistance solvent tends to inferiority by an increasing concentration of prepolymer in the vehicle

Among a large number of factors which influence the success of the overall lithographic process, the photoresist performance is a central one. Particularly, the polymer in a photoresist which undergo crosslinking or chain scission when irradiated with an energy such as UV, X-ray and electron beam, play key roles in the resist performance. Therefore, two most conventional photoresists, OMR-83 as a negative two component photoresist and AZ-1370 as a positive two component photoresist were chosen to study. After separation of base polymers from the resists by successive fractional fractional precipitation method, average molecular weight, molecular weight distribution, temperature(Tg), cyclicity and structure of base polymers were characterized

Currently, Computer-To-Plate printing system comes into wide use, an accurate color simulation system is demanded. This paper is described some basic operational expressions known in the simulation of colors by use of halftone dots, and is proposed improved color prediction of multicolor halftone, The experimental results show that proposed color predict Eq. is useful and valid in predicting the color reproduction of multicolor halftone.

Practically to put use high-photosensitive polymer, poly(vinyl cinnamoyl acetate), we investigated and confirmed UCHIDA`s synthesis, according to control solvent, which is the esterification of poly (vinyl alcohol) with monochloroacetic acid and can be freely conrolled the successive cinnamoyl acetoxyl esterfication of PVCiA, and intruducing photosensitizers,studied the photosensitivity of PVCiA.

Poly(vinyl cinnamate) had excellent resolution and no dark reaction and high etch resistent. But is was developed in polar solvent. A aqueous-photopolymer was synthesised for improvment of developability. Poly(vinyl cinnamoyl acetate)(PVCiA) and aqueous-PVCiA(PVCiA-s) was prepared and was characterized with H-NMR. The characteristic of sensitivity and developablity of coating was investigated by Grayscale method.

A cause and counterplan of the increase in dark decay rate of-CuPc/PVCz photoreceptor which is consist of the carrier generation layer (CGL) oftype copper phthalocyanine (-CuPc) thin film by an aqueous coating method and the carrier transport layer (CTL) of polyvinylcarbazol (PVCz) by spin coating, are studied in this paper. Electrochemical deposition of CGL was accompanied by an increase in work function of the aluminium substrate during the processes and the enhanced work function 5.3 eV rose above the ionization potential 5.16 eV of -CuPc. This resulted in the increased injection of holes from substrate into CGL and a fast dark decay rate. Improved photoreceptor, an electron-transport -CuPc/TNF photoreceptor, led to lowing of dark decay rate and increasing of photosensitivity. The carrier generation efficiency (ηg), carrier injection efficiency (ηi) and xerographic gain (G) of the -CuPc/TNF photoreceptor were obtained by XTOF method and PIDC.