In achieving the high productivity or producing the thin film on the T-die extrusion, processability which includes instability and film failure is often a big problem. Processability was discussed by using the theoretical analysis previously reported.
Instability was evaluated by dimensionless deformation rate which was suggested by Toriumi, and film failure was estimated by maximum stretching stress at the roll touch. Cooling air blowed off from an air knife which much influences processability made dimensionless deformation rate smaller, and it made stability better. As a result of the experiment in the various resins and process conditions, it was found that processability was dependent on dimensionless deformation rate and draw down ratio. Film failure was mainly influenced by maximum stretching stress.

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The equipment used for the plasma treatment of poly(ethylene terephthalate) fiber was a capacitively coupled flow system supplied by a 13.56MHz power source. The volume of this reactor was 2035ml, and experiments were carried out at pressures ranging from 1.0 to 2.0 Torr in an air plasma. The alkali treatment was performed with 30% NaOH aqueous solution at 50°C.
It was possible to produce samples with the same weight loss by choosing suitable conditions for each method. Comparing the samples with the same weight loss prepared by both methods, the plasma treated fabric was thicker, stiffer and stronger than that treated by the alkali solution. When samples treated by the different methods had the same stiffness, the thickness and tensile strength were also the same. The surface morphology observed by SEM was too rough with alkali treatment, and the gloss disappeared. On the other hand, the plasma-treated surface was almost as smooth and glossy as the untreated sample. The wettability was remarkably improved by air plasma even for short treatment time. From the ESCA measurements, the improved wettability is considered to be due to the increase of oxygen content of the fabric surface.
Finally, it is clear that the air-plasma treatment is an alternative good method to the alkali process for improving the quality of the PET fabrics. In addition, the plasma treatment did not deteriorate the appearance of the fabric as did the alkali process.

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Chinon fabric was treated with Pronase P, Papain C-400, or Proteoliquifase to introduce microvoid spaces into their unit fibers. Although the equilibrium moisture up-take of Chinon fabric was apparently reduced by the enzymatic treatment when it was examined at an atmospheric humidity of less than 85% relative humidity (RH). However, when the humidity exceeded 90%RH, the equilibrium moisture significantly increased by the treatment. The same fabric was soaked in water and centrifugally dehydrated. Then, the moisture of the wet fabric was compared with the equilibrium values observed in the same fabric at a high atmospheric humidity, and it was suggested that the unusually high equilibrium moisture corresponded to the water trapped by capillarity of the microvoid structure in the unit fibers of the enzyme-treated fabric. At a humidity of more than 90%RH, the equilibrium moisture of the enzyme-treated Chinon fabric was comparable to those of natural fibers such as wool, silk and cotton. The rate of water-absorbing through the surface of the treated fabric appeared to depend mostly on the enzyme used but not on the total volume of the micro-voids.

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Establishment of low temperature dyeing was performed by combining water and some primary alcohols as media for colouration of cellulose acetate fabrics.
It was noticed that increasing the dielectric constant (D) of the dyeing medium caused an increase in the colour strength of the fabrics. This increase was found to be proportional to the time and temperature of dyeing. The colour strength was also further enhanced upon using water/methanol (3:1) and mostly improved in water/n-propanol (9:1) as media for dyeing.
It was seen that the time of half-dyeing (t_1/2) and the specific dye-rate constant (k) have increased with increasing the dipole moment of the disperse dyes applied from the aqueous medium to cellulose acetate fabrics. Presence of small amounts of n-propanol as well as increasing the temperature of dyeing lowered preferentially t_1/2, and k values. The affinity and heat of dyeing were inter-related with the dipole moment of the used disperse dyes. The affinity was more improved by inducing n-propanol in the dyeing medium and decreasing the dipole moment of the dye, while the heat of dyeing had decreased with addition of n-propanol and increased with increasing the dipole moment. These findings were interpreted in terms of possible disorder of fine structure of the cellulose acetate due to presence of the aliphatic alcohols in its vicinity during dyeing.

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The photofading of Acridine Orange N in a dioxane-ethanol mixture has studied in the presence of polymers having ultraviolet absorptive groups. The results were compared with the measurements made in the presence of the coresponding ultraviolet absorptive molecules. The polymers used were: CMPT prepared by the reaction of 32.4% chloromethylated polystyrene (CMPSt), with 2-(2′, 4′-dihydroxyphenyl) benzotriazole, and CMPB prepared by the reaction of CMPSt with 2, 4-dihydroxybenzophenone. CMPT contained 4.5% 2-(2′-hydroxyphenyl) benzotriazole (HBT) unit and 27.9% chloromethylstyrene (CMSt) unit and the rest 67.6% styrene (St) unit. CMPB contained 5.1% 2-hydroxybenzophenone (HBP) unit, 27.3% CMSt and the rest % St unit. The corresponding molecules used were 2-(2′-hydroxy-4′-methoxyphenyl)benzotriazol (HMBT) and 2-hydroxy-4-methoxybenzophe none (HMBP).
In the case of irradiation with light of overall wavelengths under Xenon-arc lamp, CMPT and CMPB did not act as retarder for the photofading of Acridine Orange N in the solution, CMSt unit in these polymers underwent photochemical solvolysis in the solution to afford free HCl, which showed an accelerating action on the photofading rate of the dye. On the other hand, in the case of irradiation with light above 290nm, to which CMSt is insensitive, the effects of CMPT and CMPB were similar to HMBT and HMBP; these worked as retarder on the photofading in the order: CMPT>HMBT>CMPB>HMBP.
HBT and HBP groups acted as both quencher and screener. The quenching effect was dominant under the low concentration of these additives, and the screening effect predominated under the high concentration of the additives.

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In a doubler twisting process, it is a recent tendency to enlarge the yarn package and increase the rotating speed of the pirn. At the same time, the energy cost becomes a major part in the manufacturing cost of yarn. Therefore, it is important problem to save energy consumed in the operation process. In order to improve the efficiency in saving energy, we have investigated the relationship between the power and the diameter of the pirn, and the following results are obtained.
(1) The power to rotate the pirn consists of the force of stirring the air around the pirn and the tension of taking up the yarn. As the radius of the pirn was enlarged from 26mm to 66mm, the power to stir the air increased three times. On the other band, the power taking up the yarn slightly increased with increasing the pirn radius, although the power was almost occupied by the yarn take-up, when the pirn radius was 26mm.
(2) The coefficient of friction between the rotating pirn and the air was 0.0048_??_0.0055.
(3) The coefficient of friction between the traveller and the ring was about 0.11.
(4) When the ring was downward, both the spinning tension and the taking up torgue increased. Therefore, it was confirmed that the energy could be saved by decreasing the distance between the taking up position and guide eye.

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