Thermal decomposition behaviour of cotton fabrics graft-copolymerized with vinyl phosphonate oligomers (Fyrol 76^®) (FYR) or N-methylolacrylamide (NMA) or with combination of FYR and NMA was studied in relation to P or N contents of the treated cotton samples by Curie-point pyrolysis-gas chromatography (Py-GC) and Py-GC-mass spectrometry (Py-GC-MS). The total peak areas and most of the individual peak areas of decomposition products in Py-GC chromatograms decreased by any of three types of the treatments. The peak area of hydroxyacetaldehyde decreased most drastically to 2% of that of untreated cotton by the introduction of the lowest level of FYR. The peak area did not change further with increasing P content of the FYR-treated samples while limiting oxygen index (LOI) increased with increasing P content. In the case of NMA treatment, the peak area decreased gradually with increasing N content as well as LOI of the samples. The FYR-treated sample with the lowest P content and the NMA-treated sample with the highest N content gave the same LOI value but the peak area of the FYR-treated sample was much lower than that of the NMA-treated sample. The peak area of acrolein was found to decrease with increasing LOI, regardless of the three types of the treatments. Decomposition products formed from cellulose fractions of the samples whose peak areas increased by the treatment with FYR include furan, 2-methylfuran, and 2-furaldehyde. FYR fractions of the samples graft-copolymerized with FYR alone or combined with NMA contributed to the increase in the production of methanol. Nitrogen-containing samples yielded hydrogen cyanide, acetonitrile, and acrylonitrile. The peak areas of the latter two increased in the presence of P.

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Wool fiber and fabric were treated with dry heat (170°C/15min), super heat steam (170°C/15min) and high pressure steam (120°C/15min) respectively. Surface electric characteristics of the fibers were measured by ξ electric potetial and ESCA analysis. Effect of the heat treatments on color were investigated on the basis of the K/S measurement. Surface negative electric potential and O_1S intensity increased a little by the heat treatments. Furthermore, the fibers and fabrics were dyed with two acid dyes, levelling type C. I. Acid Red 18 and milling type C. I. Acid Blue 83. The rate of dyeing for both dyes increased with an increase of the heat treatment temperature. Saturation dye exhaustion increased especially for C. I. Acid Blue 83.

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Continuous cultivation of CW2 cells (a human colorectal adenocarcinoma tumor cell) using a hollow fiber bioreactor was investigated for the production of carcinoembryonic antigen (CEA) over 34 days. The CEA production rate increased with the increase in incubation time up to 20 days and was found to be approximately a constant value, 20ng/cm² day, after the incubation time of 20 days. The CEA production rate was known to vary in different cell lines. The CEA production rates were compared with those obtained in this study and in the literature using hollow fiber bioreactors. It was found that CW2 cells produced CEA moderately among those cell lines. The high cell density (9.1×10⁶cells/cm²) achieved in the hollow fiber bioreactor compared to the flask culture (4.0×10⁵cells/cm²) made it possible to obtain continuous high production of CEA over an extended time period.

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To regenerate chitin with high degree of N-acetylation and low degree of crystallinity, porous chitosan was N-acetylated with acetic anhydride in 10% aqueous methanol solution. Regenerated chitin (r-Ch) showed a quick dissolution in N, N-dimethylacetamide (DMA) containing 5% LiCl. In this solvent, r-Ch and poly (vinyl alcohol) (PVA) were compatible, and a series of blend films of r-Ch/PVA ranging in composition from 20/80 to 95/5 (w/w) were prepared from these solutions by coagulation in 2-propanol and subsequent drying. The miscibility of component polymers in the blends was investigated by differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectrophotometry. The glass transition temperature of the blends slightly shifted to the higher temperature region with increasing the r-Ch content, suggesting that the component polymers were partially miscible. The melting temperature and the heat of fusion of PVA in the blends decreased with decreasing the PVA content. These results denoted that the crystallinity of PVA decreased with increasing the r-Ch content, suggesting that the miscibility was higher at the higher r-Ch content region. FT-IR spectra indicated the presence of specific intermolecular interaction between the component polymers: hydrogen bonding between -OH groups.

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The bulk crystallization behaviors of poly (ε-caprolactone)-PCL have been studied by use of an optical microscope and differential scanning calorimetry. The crystallinity of PCL increased with a decrease in cooling rates during the cooling procedure from its melt; the feature was similar to the crystallization characteristics of polyolefin polymers in nonisothermal conditions. In isothermal crystallization, the linear growth rates of PCL spherulites were measured at various temperatures. The growth rate data obtained could be examined in terms of the kinetic theory of crystallization. Surface free energy of the PCL crystallite nucleus estimated from the kinetic data increased with increasing molecular weight. This implies that the fold surface of high molecular weight PCL crystallite would be covered with loose loop folds predominantly.

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Hand spinning has features that it is suitable for production of a lot kinds of yarn on small quantity and the shape of the yarn can be changed easily. But this spinning method is hardly used at present because the spinner has to have a professional skill and both the productivity and yarn quality are bad. If the hand spinning is robotized, the above weak points can be over covered, and a special yarn can be possibly produced. In this paper, at first, a hand spinning robot has been developed by measuring and anaylzing the hand spinning process. Next, hand spinning by human was compared with that by the robot. The compared result shows, in the case of spinning by human, when yarn diameter is set as a control object, yarn tension variation is small and it has a tendency to a constant value, but when yarn tension is set as a control object, the unevenness of yarn is big. However, in the case of the spinning by the robot, when yarn tension is set as a control object, the unevenness of yarn becomes small, and the mean yarn diameter is almost in proportion to a set yarn tension. It would be considered that a mean yarn diameter could be selected optionally by changing set yarn tension.

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Four kinds of polyester fabrics, Taffeta, Pongee, NKF and Milpa were deyed with disperse black dye in black shade, and then treated by sputter etching. Change in color depth was investigated by K/S and L^* on the basis of CIELAB color system. The K/S increased by sputter etching and L^* decreased. As is evident from SEM observation, innumerable fine microcraters were produced on the fiber surface by sputter etching. These microcraters play an important role for the repression of light reflectance. It is clear that microcraters contribute to the increase of the color depth of dyed polyester fabrics by sputter etching.

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