This paper will be a statement of method and results of the accelerated point distribution of floating fiber in drafting process. In order to find the accelerated point distribution, fist of all, fiber length, finess, gauge, draft ratio and form of fiber in drafting zone are decided, and then the froce used in pulling a fiber from the fiber bundle is measured. With the results of forces, the relations between air contents and drawing forces are obtained by means of Cox relation. By using the above constant and relation, point distribution can be calculated by the method of simulation. The results obtained are as follows ;
(1) Point distribution is in trigometric form.
(2) The value of the drawing force do not change the form of point distribution.
(3) Ratio K of the accelerated fiber is about 30% on roller draf ting;and is about 17% on apron drafting.
(4) The number of accelerated floating fiber is in 'proportion to the number of fiber held in the nip point of front roller.
(5) In order to produce the yarn of good quality, the fiber in front roller pert must be perfectly held, and the fiber at back roller part must be loosely held.

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The bending rigidity of the yarn with strong inter-friction is measured by elastic-ring method where the inter-fiber friction is given by the lateral compressive force applied on the yarn. That is, the yarn with tension is wound on the surface of a cylindrical tube which is made by a thin elastic plate, and the yarn tension induces the lateral compressive force on the yarn.
The rigidity of the yarn on which the lateral compressive force is applied can be calculated by the deflection of the diameter of the ring compressed by the force along its radius direction
It is found that there are two states of yarn bending process, one of them is “before slip region” in which the bending rigidity of the yarn takes a large value like as the value of a solid rod and another one is “slip region” in which the shear stress acting along fibers becomes larger than the inter-fiber-frictional force and the yield phenomena in the bending rigidity caused by the inter-fiber slip is observed. The value of the rigidity in this region becomes smaller than the value of “before slip region”.
The bending rigidity in the both regions, however, are much higher than the rigidity of the yarn which has no latelal compressional force, and takes almost several handreds times of the value of it. Effect of yarn twisting on the rigidity is also observed and discussed.

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In this paper, the drape coefficient and the mechanical properties of 138 samples of woven fabrics are measured for each of them. And the interrelation between the drape coefficient and the mechanical properties are analyzed by means of residual-regression methol ail a linear evation by which the drape coefficient can be calculated from the mechanical properties is presented.
For finding out the regression equation, a residual-regression method is applied. This method is useful for finding out the related the mechanical properties with the drape coefficient.
As a result, it is shown that the value given by³√B/Wis most related with the drape coefficient, where this value had been introduced by S. Kawabata in his research on the large deformation of bending shape of fabrics in the gravitational field. Here B is bending rigidity (g·m²/cm) and W is weight per unit area of fabric (mg/cm²).
Next, the anisotropy in the bending property of fabric is examined.
By means of multiple regression method, obtained equation to calculate the drape coefficient is as follows;
D_n=5.1+115.0³√B₉₀/W+131.1³√B₀/W+1.2³√B₄₅/W
Where B₉₀ is bending rigidity (g·m²/cm) when warp direction of the fabric is bent, and B₀ is its transverse property, and B₄₅ is its property of bias direction.
Finaly, the stability of the drape shape is examined. And it is found that the hysteresis in shearing and bending deformation of fabric is grater, the unstability in the drape coefficient becomes grater. From this fact, the experimental technique of drape testing is also discussed.

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The frictional coefficient of polyester yarn takes higher value than that of worsted yarn. And this frictional property injures the liveliness of the fabric.
The use of the lubricant is one of the method for improving this property, but there is a difficulty in weak fixing of the lubricant on the surface of fibers.
In almost cases dry-cleaning treatment washes out the lubricant from the surface of fiber.
By the corona discharge method, it is expected that the surface of the fiber is exposed to put negative ion on the fiber and the ion activate, the surface so as to promote the linking between the fiber surface and the lubricant.
It is observed that the corona discharge treatment of the yarn which is dipped in lubricant and dryed is effective when cationic lubricant is used and the frictional property of polyester spun-yarn treated is still improved even if after severe washing treatment.

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The relation between some factors composing a knitted fabric and its optical irregularity was investigated, and quantitative evaluation of knitted fabric-evenness was tried.
Light fluctuation ratio P of a knitted-fabric is given as
P=k₁logS+k₂F
where S is the number of stitches that are pressent in a scanning light, F is light absorption that represents covering degree of the knitted-fabric, and k₁, k₂ are constants.
According to the above equation, α_S and α_F can be obtained experimentally as indexes of knitted fabricevenness, As the values of these two indexes are almost coincident, we can evaluate knitted fabric-evenness by α_t that is the mean of these two indexes.
Knitted fabric-evenness index α_t, that is obtained by optical measurement as mentiond above, is in satisfactory agreement with the degree of knitted fabric-evenness that is obtained by visual judgements. So, we confirm that this evaluation method is almost proper.

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