Flat fibers and hollow fibers were prepared through the high-speed melt spinning of poly(ethylene terephthalate) (PET), and the structures of these fibers were compared with those of circular fibers. The cross-sectional shape of each fiber changed to a dull shape in comparison with that of the respective spinning nozzle. The change in the cross-sectional shape was slightly suppressed with an increase in the take-up velocity. There was a significant development of structural variation in the cross section of flat fibers in that the molecular orientation and crystallization were enhanced at the edge. Despite the difference in the cross-sectional shape, the structural development of flat, hollow, and circular fibers with increasing take-up velocity showed almost similar behavior. Considering that the tensile stress at the solidification point of the spin line is known to govern the structure development of high-speed spun PET fibers, it was speculated that the effects of the enhancement of cooling and air friction on the tensile stress at the solidification point cancel each other.

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An electrostatic chuck (ESC) is a device used to clamp and transport flat-surfaced objects such as thin semiconductor wafers. Working by the principle of electrostatic force, its functionality is limited in handling objects with rough surfaces, as the attractive forces at work are significantly reduced. To improve this weak point, by employing 70 μm diameter polymer-based electrostatic inductive fibers with a conductive core, we develop a device prototype with an adhesional mechanism having a hairy microstructure with appropriate mechanical compliance. We theoretically and experimentally investigate how the prototype works, and how the fibers’ mechanical compliance affects the performance of ESC.

On‐line measurement of birefringence was performed in the high‐speed melt spinning process of poly(ethylene terephthalate) using an apparatus that incorporates a rotating polarizer for the measurement of the optical retardation of running filament. Particular attention was paid to the detailed measurements in the vicinity of neck‐like deformation. Through the measurement at the take‐up velocity of 5 km/min, development of birefringence under the strain rate up to about 1 ms−1 was investigated. To analyze the relation between applied stress and birefringence, tension and temperature profiles of the spin‐line were calculated based on the experimentally obtained diameter profiles. Even though the strain rate is extremely high, a linear relationship between birefringence and a parameter calculated by dividing stress by temperature was confirmed to hold up to birefringence and stress/temperature values of about 0.017 and 10 kPa/K, respectively.

An electrostatic chuck (ESC) is a type of reversible dry adhesive which clamps objects by means of electrostatic force. Currently an ESC is used only for objects having flat surfaces because the attractive force is reduced for rough surfaces. An ESC that can handle objects with rough surfaces will expand its applications to MEMS (micro electro mechanical system) or optical parts handling. An ESC consisting of compliant electrostatic inductive fibers which conform to the profile of the surface has been proposed for such use. This paper aims at furthering previous research by observing the attractive force/pressure generated, both theoretically and experimentally, through step-by-step fabrication and analysis. Additionally, how the proposed fiber ESC behaves toward rough surfaces is also observed. The attractive force/pressure of the fiber ESC is theoretically investigated using a robust mechano-electrostatic model. Subsequently, a prototype of the fiber ESC consisting of ten fibers arranged at an angle is employed to experimentally observe its attractive force/pressure for objects with rough surfaces. The attractive force of the surface which is modeled as a sinusoidal wave with various amplitudes is observed, through which the feasibility of a fiber ESC is justified.