An attempt has been done to impregnate chitin/chitosan with molecular weigh between 3,000 and 5,000 into poly(ethylene terephthalate)(PET) fabric using supercritical carbon dioxide, which is non-toxic, non-flammable, cheap and easily recyclable. The final purpose of this investigation is to give high anti-bacteria property having extremely high washing durability onto PET fabric. Chitosan-lactic acid salt with a molecular weight of around 5,000 was successfully impregnated into PET fiber using supercritical carbon dioxide and the salt was impregnated in the largest amount among the materials tested, whereas no chitin could be impregnated. The fact that 70% of the chitosan impregnated into PET remained and continued to show anti-bacterial properties after the fabric was subjected to 50 cycles of home laundry washing suggests that the chitosan molecules were partially impregnated into and onto the PET surface.
Poly(ethylene glycol) and silicon oil with molecular weight from 1,000 to 5,000 were impregnated into poly(ethylene terephthalate) and polypropylene fabrics using supercritical carbon dioxide. The amounts of impregnated polymers were estimated by weighting method. The existence and the distribution of these polymer in the fiber was estimated using electron probe micro analyzer and x-ray photoelectron spectroscopy.
We have found the difference on the color between the silk fiber and the wool fiber dyed with hematein and then investigated the effect of the cell membrane complex (CMC) on the K/S-wavelength (l) curve of the dyed wool fiber to clarify the origin of their difference. First we determined the dye uptake of the cortex cells dyed with hematein and found that the uptake of cortex cells was low apparently compared to that of the wool fiber, indicating that hematein adsorbed mainly to the CMC region of the wool fiber. Further, we examined the dyeing behavior of the wool fiber pretreated by ethylene diaminetetraacetic acid (EDTA) with hematein and found that the K/S-l curve of the EDTA pretreated wool fiber is compatible with that of the dyed silk fiber. We assumed from these results that the difference on the color between the silk fiber and the wool fiber dyed with hematein can be ascribed in part to the complex between hematein and the trace metal ions included in the CMC regions.
It was investigated from a practical point of view the influence of light irradiation on the strength of drawn tape of ultra-high-molecular-weight polypropylene (UHMW-PP) prepared by the gel-casting (GC) method and the gel-like spherulite press (GSP) method. Consequently, it was found that the irradiated GC sheets prepared from 1, 2, 4 and 6 wt.% solutions had different tendencies on the change of strength by ultra-drawing. The ratio of lowering of strength increased with increase in draw ratio of both GC and GSP sheets, especially GC sheet.
Three perspectives were devised to characterize Chinese ink blurring, namely the ink absorption, the unevenness of the outlines at the blurring heads, and the difference of the tones at the blurring heads. Laboratory handsheets from softwood kraft pulp, having various basis weights, were prepared with or without wet pressing. They were soaked in Chinese ink for various times as the Klemm method. After drying, they were scanned by an image scanner set at 800 dpi to prepared bit-mapped images. These images were changed to binary images. Using the obtained images, various blurring indices based on the three perspectives were introduced. The blurring indices based on the ink absorption, the adsorbed ink amount and the capillary rise, for the handsheets without wet pressing were larger than those for the handsheets with wet pressing. Other blurring indices showed few differences between these papers with or without wet pressing. Thus, the three perspectives have different character in blots evaluation.