Measurements have been made of the color and luminance distribution (to plot the distribution curves) of the Tamamushi fabric (iridescent fabric) being illuminated by the hemisphere-shaped diffuse illuminator (light source), and then the optical properties of the Tamamushi fabric have been discussed.
1) When the Tamamushi fabric is illuminated by means of the hemisphere-shaped diffuse illuminator (light source), the iridescent effect in the fabric decreases.
2) When the Tamamushi fabric is illuminated by means of the hemisphere-shaped diffuse illuminator (light source), the color measured values of the fabric shows a color mixture between the warp ends and filling yarns.
3) The luminance distribution curves of the Tamamushi fabric are varied at the large incidence angle. It is presumably because of the effect of the shades due to the uneveness of the fabric.
4) When measurements have been made of the Tamamushi fabric being illuminated by the hemisphereshaped diffuse illuminator, there is less differences in the measured values than those measured with the parallel luminous flux.
5) If the hemisphere-shaped light source is larger than parallel luminous flux, the influence of the narallel luminous flux does not appear at the color measured.

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The loop strength of single fibers and its ratio to the tensile strength were measured for some kinds of samples having different breaking strain, which had been prepared by stretching Nylon 6, Polyester and soft stainless steel fibers by various strain. Then the bending parts of Nylon 6 fibers in the loop tests were observed under an optical microscope, and their breaking ends after the tensile or loop tests were observed with a scanning electron microscope.
The effect of tensile breaking strain on the loop strength, and the breaking mechanism for fibers in the loop tests were discussed, and the following results were obtained :
(1) It is estimated from the microscopic observation that the rupture of fibers in the loop tests begins at the outer side of the bending part.
(2) The loop strength ratio for a sample is decreased with decreasing tensile breaking strain of the sample. Strictly speaking, the relation between the loop strength or its ratio and the tensile breaking strain is dependent upon the shape or characteristic values of the load-elongation curve in the tensile test.
(3) If it is assumed that the rupture of a fiber in the loop tests takes place at the region where the sum of the bending strain e_m and the tensile strain e_f has just reached the breaking strain e_B in the tensile test of the fiber, the decrease of breaking strain Δ_e (defined as the difference between the breaking strain e_B in the tensile test and the tensile strain e_f at the breaking point in the loop test) should be nearly equal to the bending strain e_m (e_f<<1). This bending strain e_m decreases with decreasing eB, and the experimental equation Δ_e=e_m=Be_B is obtained for the samples in this experiments, where B is 0.56 and 0.95 for Nylon 6 and stainless steel fibers respectively.
(4) Above results being approved, the loop strength can be estimated from the load-elongation curve, since the load at the point on this curve where strain is equal to (e_B-Δ_e) should be the half of the loop strength.

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The porduction of pattern card for a jacquard loom depends upon the skill of craftmen which requires many labors and hours. In order to modernize such pattern card production process, a prototype of an automatic pattern card punching system has been designed using a mini computer. This system is based on three units whose main functions are as follows :
(1) Pattern Analyser
This is a device which detects the colour of a multi-colour sketch design by linewise scanning and punches out the Colour into the paper tape as a pattern signal.
(2) Signal Processing Unit (Mini Computer)
This is a unit which memorizes the colour pattern signals, and converts them into pattern weaving signals, through a stored program. And this unit controls centrally all the processing operation.
(3) Automatic Pattern Card Punching Machi
This is a machine to punch out pattern card in accordance with the pattern weaving signals delivered from the signal processing unit.
We stored the highly skillful expert craftmen's work into the signal processing unit as a program and could develop an automatic pattern card making method whose input and output are a multi-colour sketch design and pattern cards respectively. This prototype of an automatic pattern card punching system is proved to be fully practical.

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