JPS5911705B2 - induction heating roller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dielectric heated roller for use in the production of synthetic fibers.

2. Description of the Related Art Hitherto, in producing synthetic fibers such as polyester and polyamide synthetic fibers, heating rollers have been used, particularly during stretching.

This heating roller is required to have a uniform temperature distribution on its surface, and various heating rollers have been proposed. Among these, the induction heating roller is excellent in that it can provide a uniform temperature distribution on its surface. An induction heating roller has an induction heating coil in the center of the roller, a grooved or non-grooved space on the outer periphery, and water is filled in this space, and the outer periphery of the space becomes the roller. In use, the induction heating coil is energized and the outer roller is heated by electromagnetic induction. The surface temperature of the roller is maintained uniformly by heat transfer due to evaporation and condensation of the sealed water. However, as the induction heating roller is used over time, temperature unevenness tends to occur on its surface in the longitudinal direction. This temperature unevenness causes unevenness in the quality of the synthetic fibers and causes process variations such as wrapping and yarn breakage during stretching. In recent years, the drawing speed of synthetic fibers has become faster, reaching 1000 m/min or more, and the adverse effects of temperature unevenness of heating rollers have become more noticeable. The present inventor focused on the fact that temperature unevenness in the induction heating roller over time occurs due to the presence of non-condensable gas other than water vapor in the water-filled section, and discovered that the air mixed in when water is filled is non-condensable. Thinking that gas was the cause, sufficient deaeration was performed when filling the water, but this did not prevent temperature unevenness from occurring over time. As a result of further investigation, we found that the above temperature irregularities were caused not only by the air mixed in when the water was sealed, but also by the gas generated by the decomposition of foreign substances such as oil that remained in the water seal over time, the outside air sucked in during use, Furthermore, I learned that non-condensable gas such as gas generated by corrosion of the metal in the water sealing part is the cause.

As a result of extensive research in order to prevent the generation and inhalation of such non-condensable gases and to provide an induction heating roller that does not change in temperature over time, we have used an azeotropic mixture of water and ethanol instead of water as the enclosed liquid. I knew that I could achieve the above objective.

The present invention was completed as a result of further studies based on this knowledge. 25 That is, the present invention relates to an induction heating roller characterized in that an azeotropic mixture of water and a monohydric alcohol having 2 to 4 carbon atoms is used as the liquid sealed in the induction heating roller.

Monohydric alcohol having 2 to 4 carbon atoms, i.e. ethanol 30;
The composition ratio of the azeotropic mixture of propanol or butanol and water is as follows.

Ethanol 96% by weight・・・・・・・・・・・・・・・
4% water by weight, 72% propanol by weight...
...Water 28% by weight 1-butanol 58% by weight...
...The amount of the azeotrope containing 42% by weight of water is:
A suitable amount is 30 to 70% of the total volume of the enclosed space.

In addition, when using an induction heating roller filled with such an azeotropic mixture, it is preferable to use it at a temperature where the sealed space does not become depressurized but is slightly pressurized. It is preferable to appropriately select and determine the alcohol component from among the above three in consideration of the following. The surface temperature of the heating roller used to stretch synthetic fibers such as polyester and polyamide is usually 60 to 150°C.
It can be used in any desired condition. The effects of the present invention will be explained below with reference to Examples.

Example 1 and Comparative Examples When 10 induction heating rollers filled with an azeotropic mixture containing 4% by weight of water and 96% by weight of ethanol were kept at 95°C for 30 days, the surface temperature of all the rollers decreased. No change over time was observed.

For comparison, 10 induction heating rollers filled with only water were used.
When the temperature was maintained at 5℃, the surface temperature of both ends of 3 pieces dropped to 75℃ after 2 days, and the surface temperature of both ends of 5 pieces dropped to 75℃ after 7 days, and after 20 days, the surface temperature of both ends of 1 piece dropped to 75℃. The surface temperature of the sample dropped to 75°C, and 9 out of 10 samples were rejected. Example 2 28% water by weight as fill liquid...propanol 7
Example 1 except that an azeotrope with a composition of 2% by weight is used.
When the test was carried out in the same manner as above, no change in surface temperature was observed in all 10 pieces even after 30 days.

Example 3 The same procedure as in Example 1 was carried out except that an azeotropic mixture having a composition of 42% by weight of water and 58% by weight of 1-butanol was used as the filling liquid, and 10 bottles were recovered even after 30 days. No change in surface temperature was observed in all cases.

Claims (1)

[Claims] 1 Water and carbon number 2 to 4 as the liquid enclosed in the induction heating roller
An induction heating roller characterized by using an azeotrope with a monohydric alcohol.