The purpose of bale opener is to open the bale to fine and uniform tufts.Therefore, the way how to open the bale influences strongly the mean value and the distribution of tuft weight.
In the present paper, the difference between theoretical and practical tuft weight is investigated, and one theoretical and two experimental models to simulate real bale opening process are presented.Finally the effectivity of a locus analysis and two models to explain the opening mechanism are examined.
The results can be summarized as follows :
1. Mean tuft weight investigated at a opening process in commercial mills depends on a production rate of tuft and increases proportionally with the production rate.
2. There is a big difference between theoretical mean tuft weight calculated from opening conditions including production rate and practical mean tuft weight collected from actual opening process in the mills.It means that the opener spike plucks only one tuft approximately at its 15∼30 times strikes.
3. Ideal opening curve of opener's spike tip for bales is theoretically indicated as a trochoid curve and it can be classified into down-cut opening (D.C.O.) curve and up-cut opening (U.C.O.) curve.
4. It is suggested by the two experimental models that the size of tufts opened with D.C.O.are smaller and more uniform because of the smoother surface of bale formed by the strike of D.C.O.than those of U.C.O..
5. The mechanism to cause the miss swing can be qualitatively explained by experimental observations by the two experimental models.

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In order to make the frictional tangling strength of interlaced yarns clear, interlaced yarns were subjected to iterative frictional forces by reciprocating rubbers and afterward their number of tangles was measured.The frictional tangling strength is defined as the ratio of the residual and original numbers of tangles.The number of friction, friction angle, static tension, friction speed and kind of yarns were used as experimental parameters.Results obtained are as follows.
(1) When the number of friction, friction angle, static tension and friction speed are large, tangling parts easily disappear.When the friction angle is large, difference in length between filaments on inner and outer sides ofbending yarn is notable and occurrence of slip of filaments is easy and hence, tangling parts easily disappear owing to large bending angle of yarn and frictional force.When the static stress is large, the frictional force increases and hence, the above mentioned difference in filament length is large and the slip easily occurs.The friction speed has no effect on the frictional force.However, when the friction speed is large, every filament does not move and deform together with each other synchronously with the time variation of the frictional force and hence, the slip easily occurs.
(2) Yarns with more filaments or larger fineness show larger frictional tangling strength because of larger degree of entanglement and cohesion of filaments.

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The effect of the yarn cross section on the air drag coefficient and the characteristic length was examined for the spandex yarn that doesn't have a circular cross section.
The way to estimate the air drag of spandex yarns in axisymmetric air flow are investigated.Results obtained are as follows.
(1) The air drag coefficient of the spandex yarn shows similar tendency to the effect of the flat plate rather than those of sylindrical curvature appeared in the thin yarn because it has remarkable irregularities in its cross section.
(2) The drag coefficient for the fixed end yarn is the same value as that for flat plate.And the drag coefficient for the free end yarn is twice for that.
(3) It is effective and actually reasonable for the characteristic length of the spandex yarn to use the diameter that is converted from the yarn perimeter length without any consideration to its irregularity.

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In this study the relation between consciousness of environmental protection and natural resource saving on daily clothing behavior, such as purchasing and wearing, was intended to clarify.
For this purpose, the systematic survey was made for 1, 197 female university students at Kumamoto, Kobe and Tokyo.
The results obtained are summarized as :
1) When the students were at purchase of clothing, they pay keen attention to“fashionability”of clothes, including, the coordination of clothing and well-matching and they choose clothes, which have good occasion of wearing and high frequency in wearing.This behavior is consistent with environmental protection.2) Examinees had high concerns about global circumstances problems, but they did show only low concern on exhaustion of natural resources.Majority of the students consider that action against environmental protection should be firstly taken by the government and also they recognized the urgent necessity of both public and personal efforts.3) Close correlation are observed between level of consciousness of environmental protection and of natural resource saving and some items of behavior at the purchase of clothing such as (1) trial wearingbefore making purchase decision (a2), (2) cordination with other clothes already keeping (a6), (3) clothing purpose of wearing (a7), (4) not buy beyond necessity (a13), (5) buy clothes of natural fiber (a16), (6) dead-stock clothes (a21) and (7) purchase clothes one after another (a23).4) At disposal of used clothes they did not recognize clothes as valuable resource.
Generally, young students have comparatively low concern about exhaustion of natural resources caused by unduly excessive consumption and, especially the students who possess dead-stock clothes-and who enjoy the current fashion by buying clothes one after another, belong to a group of lower consciousness on circumstances and resource problems.These facts suggests strongly urgent necessity of education and enlightening activity for them about recognition of clothes as valuable resources.

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