A Novel Liquid Photoinitiator for Black Systems

Ching Fan, CHIU (Chris), Chitec Technology Co., Ltd.

Abstract:Aminoketone is the most widely used photoinitiator (PI) for black systems such as UV inks and black matrixes because it has a faster photospeed than most other PIs. However, its low solubility in monomers and oligomers is a significant drawback. To facilitate the dissolution of aminoketone small molecule reactive monomers, or solvents, are required. Sometimes lengthy grinding and gentle heating is also needed. However, new VOC rules control the use of solvents and small molecule monomers as diluents. To make thing worse aminoketone has been implicated in reproduction toxicity. The search for a replacement for aminoketone has been an urgent R&D matter receiving much attention in the UV industry. This is the first report of a novel aminoketone PI, see (2), which has high photo speed, and is odorless like Chivacure® 169, see (1) above, and is liquid at room temperature. The liquid form is an advantage that not only eliminates the need for solvents and reactive diluents, but makes it a suitable carrier for the preparation of a photoinitiator cocktail. The most significant advantage of R-gen® 919 (2) is that there is no dosage limit, while Chivacure® 169 (1) is not recommended at more than 4%. This provides a higher photo speed formulation without solubility problems. For this report the photospeed of (1) and (2) will be compared under LED lamps in various black systems and the Global registration status will also be updated.