| 摘要: | 本論文提供一新穎低遷移光固化油墨材料，可作為食品、藥品包裝於印刷時使用。近期食安意識抬頭，為避免光固化後的材料影響食品安全，油墨產業積極尋找一油墨材料其有低遷移特性的光起始劑。而市售常見的光起始劑舉凡二苯甲酮（benzophenone, BP）、異丙基噻噸酮（isopropylthioxanthone, ITX）等光起始劑皆帶有氣味，且容易從印刷品中遷移出來進而影響人體健康。為了克服此光起始劑所帶來的危害，本論文提出一種方法，透過將光起始單元與環氧大豆油（epoxidized soybean oil，ESBO）共聚並引入壓克力基單元，使之於光聚合反應（Norrish reaction）時形成網狀聚合物進以達成低遷移之效果。本論文所研發之引入光起始劑、壓克力基單元之產物ESBOa-BP、ESBOa-TX，其作為光起始劑應用於壓克力樹脂聚合時遷移率低至0.7%、0.2%。相較於單純以二苯甲酮作為光起始劑所帶來的遷移率高達87%及ITX遷移率62.9%，改善後的光起始劑遷移率下降了超過九成。除此之外，透過將光起始單元與反應性起始物單體鍵結，並將其與其他官能基化之單元共聚，亦達到降低光起始單元遷移的效果，其中pGLa-BP、pGLa-TX，遷移率低至1.5%、2.6%。
由於上述所提及之光起始單元皆透過光聚合反應（Norrish reaction）進行光固化，需要添加額外胺偕同劑（amine synergist）方可照光固化，為免除業界進行光聚合之繁瑣步驟，藉由將胺偕同劑鍵結於含光起始單元以及壓克力基單元的環氧大豆油中，即可達到低遷移自固化之光起始劑，ESBOa-BPN便為含有低遷移率以及自固化兩種特性之起始劑，其遷移率低至1.0%。並且胺偕同劑與反應性起始物單體鍵結也可達到此效果，pGLa-BPN亦為其中一例，其遷移率低至1.0%。並且更換成光起始單元ITX之pGLa-TXN，遷移率亦低至0.3%。本篇論文所提出的改性光起始單元，可解決目前光固化產業中遷移率的問題，且將胺偕同劑也一併鍵結到主幹中，能夠更進一步對光起始劑優化，在業界中非常具有未來展望性。
;This study presents a novel low-migration photocurable ink material suitable for printing on food and pharmaceutical packaging. In recent years, with the rise of food safety awareness, the ink industry has been actively seeking ink materials with low migration characteristics to avoid chemical materials affecting food safety. Commonly used commercial photoinitiators, such as benzophenone （BP）, isopropylthioxanthone （ITX）, both have odors and can easily migrate from printed products, thereby affecting human health. To overcome the hazards affacted by these photoinitiators, this study proposes a method that copolymerizes photoinitiating units with epoxidized soybean oil （ESBO） and introduces acrylic units to form a network of polymer during the photopolymerization reaction （Norrish reaction）, achieving low migration effects rates.
The developed products, ESBOa-BP and ESBOa-TX, which introduce photoinitiators and acrylic units into ESBO, achieve migration rates of 0.7% and 0.2%, respectively, when used as photoinitiators in acrylic resin polymerization. Whereas benzophenone as a photoinitiator itself has the migration rate as high as 87%, and ITX has displayed 62.9% of migration rate which is a drastic difference compared to our proposed results. Additionally, by binding photoinitiating units with monomer and copolymerizing with other functionalized units, further reduction in the migration of photoinitiating units was achieved. The migration rates for pGLa-BP and pGLa-TX reached 1.5% and 2.6%, respectively.
Given that the aforementioned photoinitiating units undergo photopolymerization （Norrish reaction） for photocuring, requiring the addition of amine synergists for effective curing, the industry seeks to simplify this process. By binding the amine synergist to the epoxy soybean oil containing photoinitiating and acrylic units, a low-migration, self-curing photoinitiator can be achieved. ESBOa-BPN, which combines low migration and self-curing characteristics, has a migration rate of 1.0%. Similarly, binding the amine synergist with monomer also achieves this effect, exemplified by pGLa-BPN, which has a migration rate of 1.0%. Moreover, using ITX as the photoinitiator unit in pGLa-TXN, the migration rate reaches 0.3%.
The modified photoinitiating units proposed in this paper can solve the current migration rate issues in the photocuring industry. By also binding the amine synergist to the backbone, further improvement of the initiator is possible, presenting a promising outlook for industrial applications. |
