Chemical shifts of aromatic carbons of phenolic compounds used in novolac synthesis commonly were recorded in aqueous alkaline solution and the results indicated that chemical shifts of para- position carbon was lower than that of ortho- position carbon, both of which were lower than that of meta- position carbons. Hydroxymethylation of some phenolic compounds with formaldehyde catalyzed by sodium hydroxide were investigated also. The research showed that hydroxymethylation could both occur at ortho- and para- positions, and occur at para- position more easily. Moreover, hydroxymethylated produts were stable in basic conditions compared with in acidic conditions. In summary, in basic conditions the lower the chemical shift of reactive site of phenolic compounds, the more easily the hydroxymethylation of the reactive site. Therefore, electrophilic substitution reaction of phenolic compounds in basic conditions can be predicted by chemical shift of reactive site. According to the regulation, a stepwise base-acid catalyzed reaction was used to synthesize various series of novolac with high Mw and low Mw/Mn, all of which have good application prospects in the field of direct digital plate-making and resists for LCD and IC.

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Polymers of substituted norbornenes were produced using palladium catalysts in the presence of formic acid (FA) as a chain transfer agent (CTA) which act to control molecular weight as well as to increase conversion. Spectroscopic analysis of these polymers by 1H NMR and MALDI-TOF MS confirmed that hydrogen-terminated polynorbornenes are generated leading to extremely low optical densities at 193 nm. Deuterium labeling studies were conducted in order to discern possible chain transfer mechanisms.

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We have investigated diffusion and deposition process of flowing Ni ions in our original micro-plating method, in which an electroless plating solution of Ni is continuously flowed into negative-type micromolds. The negative-type molds, which are made of photocurable resin, have hollow template structures. Experiments of Ni plating were carried out using one microchip containing micromolds of varied diameters. Dependences of Ni-plate thickness on micromold size were evaluated using optical micrographs, indicating that the plating efficiency was increased as the decrease in the diameter. The change of plating behavior was analyzed using a numerical simulation considering diffusion theory and Hagen-Poiseuille low. The time evolution of Ni-plate thickness was calculated from the distribution of the Ni ion concentration in the mesh neighboring the wall surface of micromolds. This simulation successfully reproduced the tendency of experimental results. It was found that the plating efficiency was strongly dependent on the flow velocity in the region near the wall surface of micromolds.

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Core-shell structured microcapsule with 0.44 μm diameter had been prepared by encapsulating the cationic photoinitiator and fluorane dye as photo-sensitive color-forming ingredients. The encapsulation ratio was detected as about 61.6%. The shell was thermal stable below 270 °C. After UV exposure for 20 s, the color-forming image density had been increased from 0.1 to 0.75. Decolorization property had been observed that the higher the temperature was, the more decrement the image density decolorized. The density decayed from 0.74 to 0.23 in just 5 min at 180 °C. It was proposed that the higher temperature influenced the decolorization process through competitive procedures. One procedure was the thermal decomposition of cationic photoinitiator to heighten color image density, and the other was to destroy the carboxy bonds in the color-formed fluorane dyes after thermal energy transmitted through phase-changed microcapsule shell. It was concluded that the latter one played a more significant role under higher temperature above 140 °C, and performed the decolorization property.

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Photochromic microcapsule had been synthesized by the interfacial polymerization technique. Polyurea polymer shell was polycondensed between -NCO isocyanate group of IPDI and -NH₂ group of TEPA. The cationic photoinitiator and fluorane dye system was encapsulated in core-shell structured microcapsule with the average size of sub-micrometer. The microcapsule was thermally stable, and showed a high optical-sensitivity to achieve color-forming reaction between the H+ proton photo-dissociated from cationic photoinitiator and the lactone ring inside the fluorane dye. Exposure for 15 s had heightened the image density from 0.1 to 0.8. By comparing the different exposing effect on photochromic image density, the color-forming reactions presented the superposition principle of exposure energy.

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Under UV light irradiation with a mercury lamp at 313 nm, a gaseous mixture of iron pentacarbonyl (Fe(CO)₅) and trimethylsilyl azide (TMSAz) produced spherical aerosol particles with a mean diameter of 0.25 μm. In the gas phase, production of hexamethyl- disiloxane was identified to support for the photochemical reactions between TMSAz and Fe(CO)₄ taking place efficiently. During propagation process in aerosol particle formation, it was suggested that isocyanate (R-N=C=O) and Si-H chemical structures were produced to modify the chemical structures of aerosol particles. Under intense laser light irradiation at 355 nm with a Nd:YAG laser, a gaseous mixture of Fe(CO)₅ and TMSAz produced magnetic ultrafine particles. Magnetization of the deposited ultrafine particles was meas- ured with a SQUID magnetometer, showing that super-paramagnetic ultrafine particles were produced in addition to ferromagnetic particles under a magnetic field of 1 - 4.5 T. Based on the nucleation reactions induced by trimethylsilyl nitrene and iron carbonyls (Fe(CO)_n n=1-4) which were formed efficiently by two photon absorption of laser light, it was strongly suggested that ferromagnetic particles were produced via chemical reactions between trimethylsilyl nitrene and two iron carbonyls and super-paramagnetic particles, via chemical reactions between two iron carbonyls.

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We have investigated the removal of poly vinyl phenol (PVP) into which was B, P and As ions implanted with a dose of 5×10¹³~5×10¹⁵ atoms/cm² at 70keV, using wet ozone. Also, we investigated the thickness of altered layer of ion-implanted PVP using Secondary Ion Mass Spectrometry (SIMS). We investigated the chemical reactivity of wet ozone and ion-implanted PVP by FT-IR. The removability of ion-implanted PVP using wet ozone decreased with increasing dose because the degrees of alteration of benzene ring and O-H group increase with increasing dose. From the results of SIMS, the thickness of altered layer of B-ion-implanted PVP was 387nm, that of P-ion-implanted PVP was 232nm, and that of As-ion-implanted PVP was 142nm. However, the degree of alteration should increase in order of B, P and As, because any samples were implanted at same acceleration energy (70keV). FT-IR indicated that benzene ring content percentage was almost same at removed and not removed. On the other hand, in O-H group, there is a clear difference at removed and not removed, O-H group content percentage decreased drastically at implanted PVP with a dose of 5×10¹⁴ atoms/cm² over. Therefore, the removability of ion-implanted PVP using wet ozone depends on O-H group content than that of benzene ring.

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The nickel micro pillars with high aspect ratio were manufactured using the negative-type resin mold. The resin master model was plated by nickel after the sputtering of gold, and was sublimated to take the products out. The pillar of 47.5 μm in diameter and 300 μm in height was produced by letting the bottom of the negative shape to be the cathode of the electroplating. The aspect ratio more than 8 was found to be achievable. The micromolding method will expand the producible size and shape of the metal micro products.

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The QCM method allows measurements of impedance, an index of swelling layer viscosity in a photoresist during development. While impedance is sometimes used as a qualitative index of change in the viscosity of the swelling layer, it has not so far been used quantitatively, for data analysis. We explored a method for converting impedance values to elastic modulus (Pa) and a coefficient expressing viscosity. Applying this method, we compared changes in the viscosity of the swelling layer in an ArF resist generated during development in a TMAH developing solution and in a TBAH developing solution. This paper reports the results of this comparative study.

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Arbitrary patterning onto inner surfaces of fine pipes with an inner diameter of 2 mm was investigated. A handmade exposure system was used as the patterning tool, and the specimen pipes were moved for relatively scanning the laser light-beam with a wavelength of 408 nm. At first, character patterns with a height of approximately 200 μm were delineated. Although several element patterns stuck out of the jointed patterns, all the delineated characters were legible, and the pattern widths were almost homogeneous except the parts where other element patterns were closely delineated. Next, arrays of V-shape patterns were delineated. Measured width fluctuation was approximately ±5 μm for the average width of 44 μm. Finally, the resolution limit or the the pattern-pitch limit of dense line-and-space patterns was investigated. As a result, the minimum pattern pitch was 29 μm, and the finest continuous resist pattern with a width of 6 μm was obtained. It was verified that arbitrary patterns were certainly delineated onto the inner surfaces of the fine pipes.

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High refractive index dispersant of silane coupling agent for nanoparticles were synthesized by thiol-ene reaction of 3-mercaptopropyltrimethoxysilane (MPTMS) and bis-(3-methylphenyl)fluorene allyl ether (BCF-allyl) . Zirconia nanoparticle dispersions were prepared by a bead milling process using this dispersant. Thus obtained zirconia nanoparticle dispersions show good dispersibility in MEK. Bis-phenoxyethanolfluorene diacrylate (BPEFA) and the zirconia nanoparticle dispersion formed homogenous mixtures in a wide variety of component ratio, and these coated thin films were photo-cured by UV irradiation with a photo-radical initiator. These hybrid thin films with zirconia nanoparticles indicated high refractive index and good transparency even at high particulate concentration.

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Nanoparticles have unique, size-dependent properties associated with magnetic, photonic, chemical, and electrical behavior, which are different from the properties in their respective bulk materials. Those properties can be controlled through the immobilization of nanoparticles on an appropriate substrate. Therefore, it is essential to construct ordered structure of the nanoparticles on solid substrate. We succeeded in the the controlled array of silver (Ag) nanoparticles on the resulting water-soluble dithiol self-assembled monolayer (SAM) nanopatterns such as line and space and dots. Spherical Ag nanopartcles were arrayed above gold nanopatterns with a gap distance of a few nanometers supported by water-soluble dithiol. The difference in attachment behavior of Ag nanoparticle between two kinds of dithiol SAMs was clearly observed.

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Three-dimensionally integrated micro solution plasmas were generated in gas bubbles in porous dielectric materials filled with gas/liquid mixed medium. The methylene blue molecules in aqueous solution were decomposed by the treatment with the three-dimensionally integrated micro solution plasmas. Decomposition efficiency was 16 times higher than conventional solution plasma in the case of applied voltage of 5 kV. With decreasing applied voltage from 5 to 2 kV, the decomposition efficiency was improved up to 360% in comparison to that of 5 kV, while reduction in the decomposition rate was 40%.

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Atmospheric pressure, Dense Medium Plasma (DMP) environments were employed to synthesize carbon-host, sole and hybrid, Magnetic- Nanoparticle Systems (MNS) and silicon and poly-halo-silane nanoparticles Systems (NPSs). Direct synthesis of functionalized NPSs and post-DMP functionalization of NPs are discussed. Plasma-enhanced partial fragmentation of low molecular weight hydrocarbons, (e.g. octane) is also presented. Advanced analytical tools were used to characterize the NPs. The design and the advantages of the original plasma tolls are evaluated. Potential importance for application of the NPSs is emphasized.

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In order to confirm the plasma processing effect at a required point by visual observation, the plasma-chemical indicator (PCI) was fabricated. In this research, the effects of NC and PA on discoloration properties of PCI was examined, since the color of prepared printing ink was fairly affected by the kind of binder. Viscosity effects of these binders on the sensitivity of PCI were also investigated. As an Application of PCI, the 3D mapping was created by the color difference ΔE^*ab obtained by 15 min of H₂O plasma irradiation using 25 pieces of PCI.
It was found that the influence of viscosity on change of color is small, comparing with the influence by the kind of binder. The expansion effect of an indicator range was able to be confirmed for H₂O and H₂O₂ plasma, but not for O₂ plasma. The optimal mixing ratio of NC and PA for H₂O and H₂O₂ plasma was 5 and 15 wt/wt, respectively. 3D mapping which visualized the situation was well in agreement with the visual observation results.

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Polyethylene films were plasma treated for the purpose of affixing dyeing sites. A methanolic 10% solution of vinyl sulfonic acid (VSA) and polyethylene glycol diacrylate (PEGDA) were used to create a dyeing site-containing resin. Dipping the CF₄ plasma pretreated low density polyethylene (LDPE) films in this solution, the films were then allowed to be penetrated for 22 hours at 75 °C and 0.2 MPa. After drying, the dyeing site-containing resin was fixed on the LDPE film by a further treatment with O₂ plasma. The fixation of the resin to LDPE films was confirmed by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). From these analysis, the existence of the spectrum of -C-O and -C=O originating in PEGDA was confirmed. The presence of a sulfonic acid group of VSA was confirmed by observation of the S 2p orbital at 163.8 eV by XPS analysis. Dyeability of the functionalized LDPE films was confirmed by coloring with a cationic dye.

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For fabrication of future flexible electronic devices, Cu films on polyimide substrate were prepared by atmospheric pressure plasma (APP) jet. The plasma jet was driven by an radio frequency (RF, 13.56 MHz), and ignited by applying RF power of 300 W to the coil after plasma-gas introduction (Ar: 1000 sccm, H₂: 10 sccm). A copper water-cooling heat sink is used as a substrate platform to avoid the thermal damage of polyimide by APP jet. To prevent the oxidation of deposited film, the effects of adding H₂ into Ar plasma gas and replacing air to nitrogen atmosphere were studied. Stylus profiler was used to measure a thickness of each film. The surface morphology and roughness of the Cu films were measured by AFM and SEM. The characterization of Cu films on polyimide was investigated with XPS.

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Photopolymers have been used in many fields such as adhesion, coating, printing, and electronics. However, UV irradiation leads to volume shrinkage with undesirable influence on adhesive properties and deforming the cured materials. We established a method for in situ measurement of the shrinkage behavior to study the correlation between the volume shrinkage of photopolymers and radical polymerization reaction. The correlation between the amount of reactive acryloyl group and the volume shrinkage in the UV-induced radical polymerization system was examined. The progress of volume shrinkage was linked with the polymerization reaction. However, when the viscosity of a mixed system containing oligomers was >10 Pa⋅s, the diffusion of radical species became slower and the formation of network structure slowed down in the curing sample. It was clear that the mixed systems had a time lag between the polymerization reaction and the shrinkage behavior in the UV-curing process.

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