光安定劑配方對PU透明塗料耐光性之影響

Effect of Light-stabilizer Formulation on the Photostability of Polyurethane Clear Coatings

張上鎮(Shang-Tzen Chang)

《林產工業》 12卷1期 (1993/03) Pp. 28-55

https://doi.org/10.6561/FPI.1993.12(1).3

摘要

本試驗之研究目的係為了瞭解芳香族PU與脂肪族PU塗料之耐光性，及探討添加不同光安定劑對PU塗料耐光性之改善效果，希望能針對特定之PU塗料尋求適當的光安定劑以便提高其耐光性。測試之光安定劑有Tinuvin-1130、Tinuvin-292與Irganox-245三種，塗料之耐光性則由其表面之顏色變化、化學結構變化及濕潤性變化評估之，表面之顏色變化則以色差計分析其黃色指數、明度留存率與色差值之變化，化學結構變化則以多次內反射（MIR）紅外線光譜技術分析，而濕潤性變化則以接觸角測定之。試驗結果顯示，芳香族PU塗料很容易受光影響而產生黃化與變色；於芳香族PU塗料中添加Tinuvin-1130或同時添加Tinuvin-1130與Tinuvin-292二種光安定劑或同時添加Tinuvin-1130、Tinuvin-292與Irganox-245三種光安定劑均可改善其耐光性。雖然脂肪族PU塗膜本身之耐光性好，但是橡木以脂肪族PU塗料塗裝後仍受光之影響而產生明顯之黃化與變色；於脂肪族PU塗料中同時添加Tinuvin-1130與Tinuvin-292二種光安定劑，其室內之耐光性更加優越。

關鍵字

芳香族氨基甲酸酯塗料 ； 脂肪族氨基甲酸酯塗料 ； 透明塗料 ； 耐光性 ； 劣化 ； 變色 ； 黃化 ； 化學結構變化 ； 濕潤性 ； 光安定劑

並列摘要

The objectives of this study are to compare the lightfastness of aromatic and aliphatic polyurethane clear coatings, and to investigate the effect of three types of ultraviolet stabilizers on the lightfastness of aromatic and aliphatic polyurethane clear coatings. The ultraviolet stabi lizers tested are Tinuvin-1130 hydroxyphenyl benzotriazole, Tinuvin-292 hindered amine light stabilizer, and lrganox-245 hindered phenolic antioxitant. The lightfastness of polyurethane clear coatings is evaluated from the changes in the yellowness index, brightness retention, color difference, chemical structure and wettability of film surfaces. From the changes in the appearance of coatings it is known that aromatic polyurethane clear coating is much more susceptible to degradation induced by ultraviolet light. The Iightfastness of aromatic polyurethane clear coating can be improved by the addition of either Tinuvin-1130 alone or tinuvin-1130/Tinuvin-292 combination or Tinuvin-1130/Tinuvin-292/Irganox-245 combination into the coating. It is demonstrated that aliphatic polyurethane clear coating exhibits a good resistance to photodegradation, but oak coated with aliphatic polyurethane clear coating still shows significant yellowing on the surface after exposure to ultraviolet light. The outsanding protection against indoor light- induced degradation of aliphatic of Tinuvin-1130 with Tinuvin-292 into the coating.

並列關鍵字

aromatic polyurethane ； aliphatic polyurethane ； clear coating ； lightfastness ； photodegradation ； discoloration ； yellowing ； chemical structure change ； wettability ； ultraviolet stabilizer