白色反光鋁片製程對品質特性影響探討

Effects of Coating Process to the High Reflectance Pre-coated Aluminum Sheet

白色高反光鋁片可製作燈罩、LCD TV光源反光片，有質輕、易加工成形及散熱等優點，具開發價值。但塗膜鋁片所要求的反光率、白度值及耐蝕塗膜黃變特性較高，需在製程條件及塗料作篩選探討。本研究針對塗膜反光率、白度值及抗高溫高濕等特性影響，進行塗膜種類、厚度、烘乾溫度及前處理狀況之評估測試。為了達到高反光率R%≥92、高白度值L≥94及高溫高濕加速腐蝕試驗240小時後，色差值ΔE < 2，以實驗計劃法探討重要影響因素。S/N比結果顯示，高膜厚塗層對高反光率及防止高溫高濕銹蝕黃變現象有明顯效果。

High reflectance coated aluminum sheet is used to produce the lamp cover, reflecting plate or backlight plate for the light source. There are many benefits to use the coated aluminum sheet such as less weight, easy forming and heat conductance. In order to reach the high performance , a special manufacturing process and coating materials are investigated to make the coated high reflectance aluminum sheet. Since the coated aluminum sheet should provide high reflectance, high value of whiteness and the corrosion-resistance properties. These properties are highly affected by coating materials and coating manufacturing process.
This study develops the process and evaluates the suitable coating materials for the high reflectance product. The quality of coated high reflectance aluminum sheet will meet the criterion of reflectance R% ≥ 92, value of whiteness L ≥ 94 and the ΔE < 2 after corrosion test. The approach included experimental planning methods to investigate the effects of coating materials, chromium pretreatment, baking temperature and film build thickness. As a result, the selected coating materials could produce the high reflectance aluminum sheet and reach the criterion of the product. The results of orthogonal experiment and the analysis of signal-to-noise (S/N) ratio also shows reflectance significantly affected by coating materials, film build thickness, and the value of whiteness, corrosion also have the same results.