本研究利用接觸角量測儀對摩擦過後之配向層表面做分析,進而了解配向層表面自由能分佈情形及濕潤特性。由各摩擦方位角(Azimuthal angle)量測配向層之水接觸角及表面自由能，我們發現所量得之水接觸角及表面自由能在配向層上具有各向異性(anisotropy)的分佈。且當摩擦強度(Rubbing Strength)不斷增加時，配向層表面自由能會隨之下降，而拒水性(hydrophobic)會增強。

實驗中也發現，配向層之表面自由能及動態接觸角延遲量(Contact angle hysteresis)，在逆摩擦方向所量測之值皆比順摩擦方向高。而在各組摩擦參數中我們發現，當入毛深度在0.3mm及摩擦次數為3次時，動態接觸角延遲量在順向與逆向摩擦方向所量得之值極為相近,且製程上較容易做出相同能量分佈之配向層。

經由最佳摩擦參數之選擇，我們發現鐵電型液晶(SSFLC)器件常見的ZigZag缺陷可獲得改善。且在液晶分子預傾角及反應時間的量測中我們發現，當入毛深度在0.2mm時，增加摩擦次數會讓預傾角上升，而液晶分子弛逸響應時間會增加，開關響應時間則會減少。

In the present studies we investigated the effects of mechanical rubbing on the surface characteristics of polymer liquid crystal alignment layers. Contact angles of water droplets in contacted with the rubbed polyimide were measured using a surface tension meter, and the surface free energy of the polymer thin films were evaluated. We found that the contact angle of water and surface free energy on rubbed polyimide is anisotropic, and rubbing caused decrease in surface free energy and wettability of the polyimide surface. It was also seen that the contact angle hysteresis and the surface free energy measured in the direction parallel to the rubbing direction is smaller than that in the direction anti-parallel to the rubbing direction. We found that when the pile impression of the velvet fibers is 0.3 mm and the cumulative number of rub is 3 times, the contact angle hysteresis in direction parallel or anti-parallel to the rubbing direction will to be close.

Be suitable choosing rubbing conditions, the SSFLCs without zigzag defects was produced. The pretilt angle and the response time of liquid crystal increased with the cumulative number.

第一章　緒論 1
第二章　基本理論介紹 3
2-1液晶態 3
2-2液晶的分類 4
2-2-1熱致型液晶 5
2-2-2桿狀型液晶 6
2-3液晶的物理特性 11
2-3-1液晶分子排列之秩序參數(S) 11
2-3-2液晶集合之彈性連續體理論 12
2-3-3液晶的光學異向性 14
2-3-4液晶的電學異向性 15
2-4液晶的配向 16
2-4-1配向膜簡介 16
2-4-2液晶的配列方式 18
2-4-3鐵電型液晶配向之ZigZag缺陷 19
2-5接觸角 21
2-6表面自由能 23
2-7摩擦強度 29
2-8預傾角 29
第三章 實驗儀器與方法 31
3-1液晶樣品製作與量測流程 31
3-2UV曝光機 37
3-3摩擦配向機 39
3-4接觸角量測系統 41
3-4-1靜態接觸角量測 43
3-4-2動態接觸角量測 46
3-5光電量測系統 47
3-5-1預傾角量測 48
3-5-2響應時間量測 51
第四章 結果與討論 53
4-1接觸角量測液體對環境穩定性探討 53
4-2摩擦配向對液晶配向層所造成之表面濕潤特性 54
4-2-1配向層靜態接觸角分析 54
4-2-2配向層動態接觸角分析 58
4-3摩擦配向對液晶配向層所造成之表面自由能變化 60
4-3-1垂直配向層之分析 61
4-3-2水平配向層之分析 63
4-4摩擦配向最佳參數之選擇 66
4-5利用接觸角分析辦法改善ZigZag光學缺陷 68
4-6摩擦配向對液晶器件光電特性之影響 71
4-6-1表面自由能對預傾角之影響 71
4-6-2表面自由能對響應時間之影響 72
第五章 結論與未來工作 74
參考文獻 77
附錄 80

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