Drawn poly-m-xylyleneadipamide filament was dry-heat-treated under free tension at the temperature ranging from 50 to 230°C, and thermal shrinkage (S), birefrigence (Δn), degree of crystallinity (x), degree of crystalline orientation (f_c) and degree of amorphous orientation (f_a) of the specimens were measured . Relation between transition points observed by Arrhenius plot of 'thermal shrinkage vs. temperature of the thermal treatment and structural quantities, namely thermal retraction mechanism was investigated.
The results are as follows :
1) Transition points are observed at 75, 110 and 190°Cin Arrhenius plot, that is, the plot of the logarithm of the thermal shrinkage (log S) vs. reciprocal of the absolute temperature (1/T). In the plots of Δn, x, fc and fa vs. 1/T, transition points are also observed at 50, 70, 110 and 180°C. There is a good relationship between thermal shrinkage and structural quantities.
2) The transition point at 50°C is assumed to prior glass transition temperature in the slightly wet state and the thermal retraction caused at the temperature ranging from 50 to 75°Cis due to the disorientation of amorphous chains in the same state.
3) The transition point at 75°Cis glass transition temperature, and the retraction caused at the temperature between 75 and 110°C is deduced from the disorientation of amorphous chains and the retraction of amorphous chains under tension induced by folded chain crystallization.
4) The transition point at 110°Ccorresponds to the crystal grain boundary relaxation, designated as ai, and the thermal retraction caused at the temperature ranging from 110 to 190°Cis assumed to be mainly the retraction of amorphous chains under tension induced by folding.
5) The transition at 190°C is assigned to the crystal disordering relaxation, designated as ct2, and the retraction in the range of 190 to 235°C is due to the rearrangement of molecular chains and partial melt. Melting point of this polymer is 235°C.

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The relation between the sliver quality and the inclination of the flasts was examined, in both cases of 90°C and 75°C of the flat acting angle, on a carding machine equipped with a cylinder mcunted with metallic wire and a doffer with a wire fillet card clothing. The correlative effects ofthe inclination of the flats and cylinder speed was also examined.
The results obtained are as follows ;
(1) With the flat acting angle of 90°C, and that of 75°C, the inclination of flats in which the amount of neps in the sliver is the smallest is respectively 1/56.5 and the already known 1/37.5.
(2) The smallest amount of neps in the sliver at a flat acting angle of 90°C is much smaller than that of 75°C
(3) The fiber damage slightly increases as the inclination of the flats decreases.
(4) The above results are independent of cylinder speeds.

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This article aims to develope the automatic loom for splashed patterns.The following results are obtained.
(1) This loom is provided with a single rapier for weft insertion.Apositive camand balls orthe combined mechanism of elliptic gears and a crank oscillate a rapier right and left.
(2) The mechanical or electrical control mechanism has been developed to detect the gap of patterns.
(3) The automatic loom for a splashed pattern, appling the electrical paint and some attachments has been developed.

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