The characteristics of the heater have an important bearing on the processing of textured yarn. This article concerns the development of an efficient heater of non-touch type. It deals with some of the heat properties of this type of heater and describes a method by which the degree of heat-setting of yarn passing through the non-touch type heater can be quickly measured.
The electric power required for heating running yarn has been measured by varying the yarn speed, yarn denier and the temperature of heater-setting (the temperature at which the heater is set). These values have been compared with the DTA curve and the degree of birefringence and of contraction of the yarn.
The results obtained are:
(1) The electric power consumed for heating running yarn is measurable accurately and quickly from the working time of automatic temperature control.
(2) The degree of heat-setting of yarn can be estimated from power consumption.
(3) The temperature of the heater at which power consumption begins to decrease is the best temperature for heat-setting yarn. We can define it as the temperature for heater-setting.

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We have studied the utility of radiant ray (infra-red ray) for the heater of the false-twist texturing machine. The previous article referred to the relation between the degree of heat- setting of yarns and electric power consumption in the processing of textured yarns, and showed the characteristics of the infra-red ray heater.
The present article discusses the physical and mechanical properties of specimens treated with both IR-ray and non-IR ray. Non-IR ray treatment is accomplished by the same heater as IR-ray treatment. The inner surface of the heater is covered with Al foil to shut off IR-ray.
The specimens used in our experiment were uniform in length or subjected to various drawings.
The results obtained are;
(1) The same temperature effect is obtained by IR-ray treatment in 35-40°C lower temperature range than the one by non-IR ray treatment.
(2) The rate of drawing has a slighter bearing on yarn than with the heat treatment temperature particularly by IR-ray treatment.
(3) Crystallization is promoted in specimens treated with IR-ray, and it is believed from DTA curves and photographs of small-angle X-ray scattering that the distribution of crystal size varies.

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The previous article dealt with the fundamental behaviors of nylon 6 fibers subjected to thermal treatment with super heat steam under atmospheric pressure and compared them with those treated with dry heat.
This article concerns the effect of heat treatment with steam of running yarns (non-twisted and false twisted yarn) and compares it with the effect of treatment with dry heat.
1) The thermal effect on the density of non-twisted nylon 6 yarn shows exactly the same tendency (i.e., minimum point at about 150°C) as in the previous article. In false-twisted yarn, the density gradually increases as temperature rises.
2) The surface filaments of false twisted yarn are affected by the relative humidity in the treatment chamber. Its inner filaments are influenced by the moisture which the filaments absorb before treatment.
3) The crimp of yarn texturized with steam is superior in character to the crimp of yarn treated with dry heat.

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Most wet processes can be more safely and more economically carried out with the aid of the control techniques of today.
In this paper, we theoretically analyzed the behavior of neutralization process in wet processing using well known mass transfer equations for the purpose of automatic controlling its acid concentration.
Based on this analysis, feedback control was applied to a real neutralization bath concentration in mercerization processing by means of automatic titration method.
As the result, we obtained satisfactory data for the practical process by this control method.

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The previous paper analysed the flexure of a pair of mechanically similar rubber-covered rollers, assuming that the elastic property of the covering and of the fabric was uniform over the width of the covered rollers, and that the working width of the rollers and the width of the fabric were the same.
Actually, however, a fabric has selvages, the hardness of the covering does not remain uniform after repeated use, and the fabric is smaller in width than the covered rollers. The important problems concerning these factors can be solved theoretically by using the fundamental equations derived in the previous paper, if the spring constants of the covering and the fabric are assumed to change abruptly at some position near the edges of the covered rollers.
As the results of calculations, the following conclusions are obtained:
(1) The effect of selvages on the load distribution is not as noticeable as the effect of the difference in elasticity of the roller covering between the inner and outer regions. However, the change in the spring constants is not abrupt but continnuous in actual practice. Hence some effect which should not be ignored may arise in the transient zone, if the spring constants differ widely.
(2) When the spring constants of the roller covering vary from place to place, the uniformity of the load distribution deteriorates considerably.
(3) A fabric narrower than the rollers has rather a good effect on the load distribution, as is usually believed. There still remains the chance that the lower load in the region outside the fabric may reduce the load on the fabric near the edges.

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