鎂合金因其質輕和價格低廉等特性，在各個產業中的使用量日益增加，但因其不耐腐蝕，限制許多作用，所以使用微弧氧化技術作表面處理，又在市場的需求下，外觀也日益受到重視。本實驗使用微弧氧化後的AZ31鎂合金板材，使用反應性染料成功對其進行染色，但其耐日光牢度差，無法達到工業上照射200小時的要求。本實驗用不同染色條件探討其耐日光牢度，然後進行耐日光改善處理，由實驗結果顯示在pH12溫度70℃濃度3%下塗佈後可從50小時提升到200小時，且有最佳△E值為4.06，為改善耐日光最佳的條件。

Features such as lightweight and inexpensive of magnesium, increasing use of in various industries. But its impatience corrosion,it limit many of the functions. Therefore, using the micro-arc oxidation (MAO) to improve it. Appearance is also more and more attention of the commercial demand. In this study, using micro-arc oxidation on the AZ31 magnesium alloy sheet and reactive dyes successfully dyed in themicro-arc on the magnesium alloy sheet.But it show poor light fastness.It can not requirements of industry exposure in irradiation200 hours. This experiment to investigate the light fastness of different dyeing conditions, resistant to sunlight then proceed to improving the handling. Inferred from the results,in the pH12 Temperature 70 ° C the concentration of 3% can upgrade from 50 hours to 200 hours by coating HS-670 A,B plus Eversorb AQ1. And best △ E value of 4.06. For the best conditions for improving the resistance to sunlight.