光引發劑對紫外光硬化透明壓克力塗料性質之影響

Effects of Photo-initiators on the Properties of UV-curable Clear Acrylic Coatings

周佰隆(Pai-Lung Chou) ； 張上鎮(Shang-Tzen Chang)

《林產工業》 18卷2期 (1999/06) Pp. 185-193

摘要

紫外光硬化塗料乾燥後，殘存在塗膜中的光引發劑與其衍生物常會促使塗裝材光劣化。本試驗以芳香族與脂肪族胺基甲酸酯變性壓克力樹脂為紫外光硬化塗料之低聚合體，探討Irgacure 651與Irgacure 184兩種光引發劑及不同添加量對透明塗裝紅櫟木表面性質及耐光性之影響。試驗結果發現若僅以1% Irgacure 651為光引發劑，塗膜硬化所需照光時間較長，以3% Irgacure 651為芳香族胺基甲酸酯變性壓克力塗料之光引發劑，所得塗膜之硬度與耐磨性等機械性質比較好。此外，經過耐光試驗後，不論使用芳香族或脂肪族胺基甲酸酯變性壓克力塗料，以Irgacure 651為光引發劑塗料塗裝紅櫟木之光變色均較以Irgacure 184為光引發劑者明顯，其中，又以芳香族胺基甲酸酯變性壓克力塗料塗裝試材之差異較顯著。分析塗膜與膜下紅櫟木之光變色，發現亦以使用Irgacure 651之芳香族胺基甲酸酯變性壓克力游離塗膜的光變色較嚴重。

關鍵字

紫外光硬化塗料 ； 壓克力 ； 光引發劑 ； 光變色

並列摘要

Photoinitiator and its derivatives remained in coating films after photopolymerization of UV-curable acrylic coatings are harmful to the durability of clear coated wood. To investigate the effects of dosage and type of photoinitiators on the film properties and durability of coated oak, Irgacure 651 and Irgacure 184 were selected as photoinitiators for aromatic and aliphatic urethane modified acrylic coatings in this study. The results reveal that when the dosage of Irgacure 651 is 3%, the film properties such as hardness and abrasion resistance are better than those using 1% and 5% Irgacure 651, and longer UV irradiation time is needed for curing of aromatic urethane modified acrylic coating containing 1% Irgacure 651 photoinitiator. After lightfastness test, the discoloration of oak coated with either aromatic or aliphatic urethane modified acrylates using Irgacure 651 as a photoinitiator is more significant than that using Irgacure 184 photoinitiator. Among these samples, oak coated with aromatic urethane modified acrylic coaling shows most significant yellowing after lightfastness test. The discoloration of free coating film of aromatic urethane modified acrylate using Irgacure 651 is also more severe than free coating films of other coatings.

並列關鍵字

UV-curable coatings ； Acrylate Photoinitiators ； Photodiscoloration