Polymer cluster orientation and optical phase retardation of the rubbed polyimide surfaces

Abstract

ABSTRACT:In an atomic force microscopic image of the main-chain-and the side-chaintype polyimide surfaces, we have observed a variation of the surface morphology to use the rubbing depths and the rubbing times. On the rubbed polyimide surface, the polymer clusters are aligned in long chains along the rubbing direction. The topology of the polyimide surface is weakly changed at a lower rubbing depth, but it is greatly changed at a deeper rubbing depth. Once the polished string structure is obtained, no considerable changes in the surface topography of the polyimide are visible, although rubbing times are increased from 1 to 8 at constant rubbing depths (0.3 mm). The rubbed polyimide films show optical phase retardation, which was steeply increased with increasing rubbing depth; but it was increased very little with increasing rubbing times.

Fabrication of Rubbing Cloths with Various Pile Densities for the LCD Process and Their Effects on Rubbing of Polyimide Alignment Layers

“…배향막의 표면 분석 폴리이미드 배향막은 러빙과정을 거치면 표면에 큰 형상 변화가 나타난다 [14]. 이러한 러빙 전·후의 배향막 표면의 변화를 AFM(atomic force microscopy) 이미지를 통하여 분 석하였다.…”

Alignment layers based on poly(oxadiazole‐naphthylimide)s: New aspects on tuning anisotropy of the surface morphology and adhesion via rubbing

“…These images highlight clusters of different size, randomly distributed all over the investigated surface. This is most likely due to the π-π stacking interactions developed between naphthyldiimide segments upon solvent evaporation, or even due to the spherical clusters formed by polymer chains in the solvent, which remain slightly deformed on the surface after evaporation 34,35. The use of height images, whether 2D or 3D, usually does not provide enough information about the fine details ofT A B L E 2 The results of the consistency index and flow behavior index at various concentrations for the PI-Nf and PI-NfCO solutions , concentration of the PI solution; k, consistency index of the sample; n, flow behavior index of the sample.…”