SynopsisModel reactions were carried out using coniferyl alcohol (CA) which was one of the unit structures for lignin(L). Firstly, an epoxidized CA (ECA) was synthesized by reaction of CA with epichlorohydrin. The ¹H-NMR spectrum showed that not only the phenolic hydroxyl groups but also the alcoholic hydroxyl groups were epoxidized. And then, it was confi rmed that epoxy groups of ECA could react with hydroxyl groups of CA according to expectation. From above mentioned model reactions, the possibility of the cured epoxy resin based on about 100% biomass was suggested. After the confi rmation of the reactivity of hydroxyl group of CA with epoxy group of phenyl glycidyl ether (PGE), the curing reaction of epoxy resins using bisphenol A diglycidyl ether (DGEBA), by L was examined. The cured epoxy resins showed the glass transition temperature of around 151℃ which was 20℃ higher than that of the conventional DGEBA cured by petrochemical phenol novolac and the residue after heating at 500℃ by thermo gravimetric analysis was also 10% increased.(Received December 9, 2010 ; Accepted January 25, 2011)

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SynopsisA more sustainable society by promoting global production that reduces the environmental burden of a product throughout its life cycle is required. We are currently researching the use of woody biomass, particularly the application of woody lignin to the epoxy resin widely used in modern electric and electronic equipment. We have investigated the use of lignin derivatives as molding materials. Melt viscosities of molding compounds containing lignin derivatives as hardening agents were higher than that of a commercially-available molding compound. However, other mechanical and electrical properties of hardened compounds were comparable to those of the hardened commercially-available molding compound. We have successfully applied the molding compound containing lignin to mold a stator of a prototype of motor. Results suggest that woody lignin has great potential for application to electric devices.(Received February 28, 2011 ; Accepted April 11, 2011)

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Synopsis What is critical for reduction of carbon dioxide (CO₂) emissions is to reduce the emissions from transportation sector that account for approximately 20% of the total. Especially, in the aircraft and automobile fields, improvement of fuel effi ciency by lightening of the body weight of aircraft and automobile is one of the most effective strategies in reduction of CO₂ emissions. For aircraft and automobile, respectively, a 20% and a 30% reduction in weight can be achieved by using Carbon Fiber Reinforced Plastics (CFRP) as constructional materials, resulting in a 7% and a 16% reduction in CO₂ emissions. In order to use CFRP as alternative lightweight and high stiffness materials to metals, it is important to design matrix resins to effectively refl ect high specifi c strength and specifi c modulus of elasticity of carbon fi ber in CFRP properties. Furthermore, reduction of production cost and improvements of production effi ciency are required for wide use of CFRP in the aircraft and automobile fi elds. Therefore, cost reduction by various innovation methods for molding and drastic improvement in production effi ciency have been tried in terms of designing matrix resins. Moreover, CFRP have an important part in energy sector such as windmill, hydrogen tank and so on. Matrix resins are expected to play an increasingly signifi cant role in expanding coverage of using CFRP in the transportation and energy sector for reducing CO₂ emissions.

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SynopsisCresol formaldehyde novolac resins (Cre/Form) having hard properties cannot be applied minutely the positivetype photoresist material onto dry fi lms. Therefore, a new development was needed, so we carried out the synthesis and application of cresol novolac resins having fl exibility. The polycondensation reactions with cresols(Cre) and glutaraldehyde(Glu) were carried to obtain cresol glutaraldehyde novolac resins(Cre/Glu). Cre/Glu having both a dissolving rate foralkaline aq. solution below 1000Å/s and M_w over 2000 were chosen for the test. The 5μm thick cast fi lms of Cre/Glu were applied onto polyimide fi lms in order to evaluate the fl exibility properties of the obtained resins by observation of their bent parts. Though the Cre/Form resin of the bent part was scattered, the Cre/Glu resin was settled with just cracks. The fl exibility of the Cre/Glu resin was also confi rmed from the results of the dynamic storage modulus measurement, too. The lithography performance of the Cre/Glu resin coated 1.5μm in thickness onto the silicon wafers was examined. The residual membrane thickness was high (98%) and the resolution of the resist was up to 2.5μm.

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SynopsisCopper nanoparticle was produced from copper(II) hydroxide by chemical reduction using hydrazine in resol methanol solution. The characteristic of this process was as follows; (ⅰ) the surface of copper nanoparticle was coated by phenolic resin as soon as copper nanoparticle was produced, (ⅱ) oxidation or cohesion of copper nanoparticle scarcely happened, and (ⅲ) copper nanoparticle was nighly fi lled up in phenolic resin with nanoscale dispersion. As the content of copper was increased, the volume resistivity of the ink produced with copper nanoparticle dispersion was lowered. The volume resistivity of the printed ink consisting of 9wt% phenolic resin and 91wt% copper nanoparticle was low and closet those of copper foil for printed wiring.

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