We attempted to fabricate silk resin sheets from silk powder using a hot-rolling equipment for continuous production. Silk powder was mixed with water, wrapped in a packaging material, and then passed through the nip between the heated rollers. Pulp sheet was suitable for the packaging material, while no resinification was observed using PETF sheet and aluminum foil as the packaging material. The resinification area increased with increasing temperature on the roll surface from 100 °C up to 150 °C under the condition of the water addition and rolling reduction ratio at 20 mass% and 70 %, respectively. The resinification area reached 90 % at more than 60 % of the rolling reduction ratio under the 20 mass% of water addition and 130 °C of the roll surface temperature. X-ray analysis showed that all the silk resin sheets consisted of silk II crystal structure. In addition, the broadening of FT-IR absorption peaks may be attributed to the formation of random-coil structure and Silk I. The bending strength of the silk resin sheet by the three-point bending test became lower with an increase in the rolling reduction ratio. The bending strength of the silk resin sheet exceeded 100 MPa at 40 % of the rolling reduction ratio, which was almost equivalent to that of the silk compact fabricated by pulse electric current sintering reported previously.

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As one of valuable cultural assets, paper materials have been conserved in museums and libraries. However, a solvent, water employed in conventional processes has danger of destroying the paper due to deformation occurred during wet and dry treatments. In this study, supercritical carbon dioxide (scCO ₂ ), that is a fluid beyond critical point of pressure and temperature was used as a new solvent. The scCO ₂ can penetrate in micro- and nanospace owing to its extremely low surface tension with carrying substances while it does not adsorb on hydrophilic materials causing no swelling of them. Therefore, the use of scCO ₂ is expected to neutralize acid paper without damage. In the experiments, an acid paper without printing was accumulated in multi-layers and treated on batch processing with three organic bases, monoethanolamine, triethanolamine that are applied in conventional methods and triethylamine that is relatively dissolved in scCO ₂ . The pH of the paper increased from 5.5 to 7.0 or 7.5 after 1 hr-treatment, suggesting deacidificaiton of the paper by all organic bases in scCO ₂ containing methanol. The acid paper handled with triethylamine in scCO ₂ / methaol was neutralized faster without yellowing as compared with ethanolamines or by a vapor- and liquid phase methods. In addition, the tensile strength of the paper was not significantly influenced by the base treatment in scCO ₂ . The buffering effect of triethylamine impregnated in the acid paper lasted more than six months. Furthermore, fifty sheets of the acid paper were uniformly neutralized by scCO ₂ method using triethylamine.

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A new method for the surface modification of polyurethane (PU) nanofibers by using a hyper branched polymer containing fluoroalkyl group (FF1) was developed. PU nanofiber mats containing FF1 were obtained by using a solution electrospinning method. The effect of the addition of FF1 on the structure of the PU nanofiber mat has been investigated with a scanning electron microscope and X-ray photoelectron spectroscope. Furthermore, the physical properties of the nanofiber mats such as a contact angle measurement, water resistance test, water vapor permeation test and tensile test have been studied. X-ray results show that almost of FF1 particles are located on the near-surface region of the nanofibers. It is found that the particles improve remarkably the surface properties of PU nanofibers.

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Cashmere, wool and yak were reduced with dithiothreitol in 0.1 M phosphate buffer (pH 7.8) containing 4% sodium dodecyl sulfate at 95℃. Keratin proteins were extracted with around 80% yield. Higher SDS concentration and temperature were important factor for effective extraction of keratin proteins from wool and animal fiber. More than 8 bands were observed in SDS-PAGE analysis of extracted proteins. Maldi-Tof mass analysis of tryptic digests of major bands in SDS-PAGE and data base search showed that those bands are assigned to be keratin I and II. Typical peaks for keratin I of cashmere, wool and yak were observed in the region between 2500 and 2700 m/z in mass spectra and these peaks were shown to be very useful for identification of cashmere, wool and yak.

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