When the PET film is drawn to about 4 times at first stage, the transverse line structure is observed under the polarized optical microscope (POM) and the scanning electron microscope (SEM). These transverse lines extended and slightly undulated perpendicular to the draw direction. Consequently, the transverse lines are distributed perpendicular to the draw direction.
From the observation of the POM and the SEM and the results of the S-S curve and of the birefringence of PET films, it can be considered that the transverse line structure is composed of the “squeezed structure” and the relaxed craze-like structure.
PET film with the transverse line structure shows the unique polarized light scattering patterns when the incident beam has the component perpendicular to the draw direction, and that the light in this pattern oscillates in the draw direction.
The “polarized pattern” shows four leaf-shaped patterns not only in the front but also in the back. The intensity of the “polarized pattern” in the negative direction is weak.
Such “polarized pattern” can be observed when the transverse line structure extends perpendicular to the draw direction. When the transverse lines are inclined perpendicular at 3.8°, the “polarized pattern” is changed into the pair of two leaf-shaped patterns.
The incident beam reflects and transmits repeatedly at the boundary between two layers which have different densities and refractive indices. Consequently it is considered that polarized light vibrating in the horizontal plane is observed.
Such optical property of the PET film is similar to a half-wave plate or an optically active substance, which is, however, substantially different from the PET film. This is because the “polarized pattern” in this paper does not depend on the thickness of the sample films and light vibrating perpendicularly to the draw direction is changed into the one vibrating in parallel to the draw direction and not vice versa. There is a possibility of applying the PET film to an optical element, such as an optical isolator and an opto electric integrated circuits.

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High density medium molecular weight polyethylene (MMWPE, Sholex S5008, _??__η=1.6×10⁴) blended with ultra-high molecular weight polyethylene (UHMWPE, Hizex Million 240M _??__η=1.5×10⁶) was melt-extruded at a comparatively high take-up speed to make films which had well developed lamellar crystals whose interfaces orient perpendicular to its machine direction. Stressstrain tests were performed at room temperature on the as-spun and annealed films. The Young's modulus, the yield stress and both the elongation and the stored energies at 50% strain increased with increasing UHMWPE content, while only a small changes were caused in the recoverabilities in the energy and length. The structures of the films before and after stretching were investigated by scanning electron microscope, wide-angle x-ray diffraction and small-angle x-ray scattering.

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As we have mentioned in the previous paper¹⁾, we are developing a three dimensional CAD system for dress, where one can estimate and display the shape of appearance of a dress put on a body, by inputting the following data; 1) paper pattern for the dress, 2) mechanical characteristics of the cloth, 3) shape of the body. We also explained our concept of paper patterns with complete information for sewing and dressing, and the method to triangulate them.
In this paper we describe the construction of topological structure of the dress by sewing the planer triangulated pattern, and the rough estimation of the shape of the dress from the information for dressing. These steps directly follow the triangulation and prepare suitable three dimensional initial state for the succeeding iterative numerical analysis to obtain the mechanically stable state of the dress. Our method is applicable to almost any kind of topology of connection at sewing lines and to any position of the body to put the dress.
Therefore, we believe that the capability of our system described above enables us to simulate almost all kind of dress designed and produced in current apparel industries.

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The reaction of polyester fiber with the sodium hydroxide solution was studied at 60°C, and 95°C. The weight of fiber decreased following decrease in denier, although only small change in strength per denier was observed. Elongation, Young's modulus and degree of crystallinity of obtained fibers were measured. Contents of hydroxyl and carboxyl end groups of polyester were determined. The number of carboxyl group increased by this reaction and that of hydroxyl group decreased. Moisture regain of the fiber increased from 0.4 to 1.8 per cent, proportional to the number of carboxyl end group on the fiber.

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An idea to estimate the pressure brought on a human body by his clothes from the measurements on the deformation of the fabric is presented with a few experimental verifications. To this end, an experimental model system is used; a rubber film substrate and a sample fabric model are put on an even stage, and they are fastened by a circular or an elliptical ring; the fabric together with the rubber film is ballooned into a dome-like shape by air pressure; the air pressure measured is a direct estimation for the garment pressure.
For the indirect estimation, the strains of the threads are measured and transformed into the tensions through their stress-strain relationships; the garment pressure (P) is calculated through the relation
P=N₁/R₁+N₂/R₂,
where N₁ and N₂ are the effective tensions in the directions corresponding to the principal curvatures R₁ and R₂. The pressure thus estimated coincides approximately with the one measured directly.

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Fine structures of chitosan films, prepared from the liquid crystalline solution under shear deformation, were investigated by using the polarized microscope and the X-ray diffraction technique.
The cast film (L1) showed the so-called “banded structure” similar to those found in other rigid polymers such as aromatic polyamides¹²⁾, cellulose derivatives^13-15) and polyamino acid derivatives¹⁶⁾. The banded structure did not disappear even when the cast film was treated with a 4% aqueous NaOH solution, methanol or water and then dried. However, the crystal structure was changed by these chemical treatments. Especially, it was noted that the crystallinity increased and the crystal perfection proceeded by the alkali treatment or the water swelling after the methanol treatment. This suggests that the water molecule plays an important role in the chain packing of chitosan molecule on the formation of crystal.

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The sorption behavior of an acid dye, C. I. Acid Orange 7, on S-carboxymethylated keratin cast films structurally altered by stretching and heating has been investigated in relation to the α-β structural transformation of keratin. An apparent difference in the equilibrium dye uptake between the structurally altered keratin films was observed. However, there was a little difference in apparent dyeing affinities of the dye. The amounts of the dye uptake by the films were in the order; unstretched (disoriented α-helix structure)=heat-treated (disoriented β-structure) ⟩ stretched (oriented β-structure) films.

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