The alignment of a ferroelecric liquid crystal on polyimide LB (Langmuir-Blodgett) films was investigated. Among the samples examined, a polyimide prepared from p-phenylenediamine and 3, 3′, 4, 4′, biphenyl tetracarboxylic dianhydride was the best material in order to obtain high orientation of ferroelectric liquid crystal molecules. When the conformation of the main chain of polymer molecule was linear, the higher ordering of the liquid crystal molecule was achieved.

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Polyester fiber was treated in the aqueous solution of ethylenediamine at 90°C, and the change of the properties of the fiber was investigated as well as that of the molecular weight and the amount of end groups. By the treatment, the weight of the fiber was lost, the strength and the elongation were diminished, and the moisture regain increased. The molecular weight was considerably reduced by this treatment. During the reaction, the increment of hydroxyl end groups were about the same as that of carboxly end groups. It was considered that the scission of polyester chains took place at the middle of the polymer, and both hydroxyl and carboxyl groups were produced.

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We developed a three-dimensional apparel CAD system which simulated sample making and draping processes. In this paper, we explain the sample making system. Using this system, we can predict the shape of garment without actually making and fitting it. The basic idea for the system is that the natural shapes of garments are determined by four main factors, namely, mechanical properties of material fabrics, geometrical and topological shapes of paper patterns, shape of the human body and the way of dressing. The predicted shape of a garment changes according to these four factors. For example, there is some difference between the same pattern worn by different persons. Here we focus on the mechanical formulation of paper patterns and garments. To formulate them, we use the finite difference energy method which is one of the finite element discretization procedures. In terms of structure analysis, to predict the shape of garments is a large deformation and contact problem. To solve the large deformation problem, total Lagrangian formulation is employed in which 2nd Piola-Kirchhoff stress and Green-Lagrange strain are used. As for the contact problem, the existence of the human body is interpreted as a constraint condition. So, we describe the formulation of body surface. Finally we give some examples to show that this system is applicable to a wide range of garments.

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We developed a three-dimensional apparel CAD system which simulated draping and sample making processes. In this paper, we explain the draping system. Usually draping means a technique of making paper patterns by draping a cloth around a dummy. It is difficult to simulate the process directly. So, we separate the process into two sub-processes. The first process is to generate three-dimensional shapes of garments or to measure the shape of a human body. The second process is to develop the three-dimensional surface on a plane surface. Here we focus on the technique of the second process. The technique is based on a mechanical calculation using a finite element method. The system consists of the following sub-programs. 1) Input a three-dimensional curved surface. 2) Input the mechanical properties of material fabrics. 3) Input the indication of the area to flatten. 4) Input the boundary conditions. 5) Divide the area into the triangular elements. 6) Make an initial plane surface. 7) Calculate the plane surface which is best fitted to the three-dimensional surface. 8) Output the best fitted plane paper pattern. 9) Output the strain and stress distributions where the plane surface coincides with the threedimensional surface. Using this system, we can obtain the best fitted paper pattern. The stress and strain distributions are used to evaluate the paper patterns. When a three-dimensional curved surface is fixed, we can obtain many paper patterns according to the mechanical properties of material fabrics and locations of darts. Finally we give an example to show that this system is applicable to a real problem.

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The effects of the ratio of mannuronate (M) and guluronate (G) (M/G ratio) of alginate on the physical properties of alginate fiber paper were investigated, by using five kinds of divalent metal ions, Cu, Ba, Ca, Ni, and Zn as the coagulant of alginic acid gel. At the same M/G ratio, the calcium- and nickel-coagulated fiber papers had similar strengths. Burst strength and breaking length increased with the increase in M/G ratio. On the other hand, tear strength decreased with the increase in M/G ratio except a few samples. These findings mean that the effect of the increase in M/G ratio on Ca- or Ni-alginate fiber pulps is the same as that of beating on cellulose fiber pulp, within the range of M/G ratio of this experiment. Electron microscopic observation revealed that little fibrillation occurred with the alginate paper with a M/G ratio of 1.19 but the fibers seemed to adhere in fusion. Thus the interfiber cohesion is thought to be a cause of mechanical strength of alginate fiber paper and the adhesion is governed by M/G ratio and by kind of metal ions.

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