Development of water-based photocurable materials (3)

2.4 Water-Based Fatty Epoxy Resins These resins differ from water-based epoxy acrylate prepolymers in that hydroxyl groups in polyoxyethers react with anhydrous anhydrides such as maleic anhydride to introduce hydroxyl groups. Reaction with the same 1.3.

2.5 Polyacrylate Emulsion with Acrylate

Most of this system is copolymerized with acrylic acid to introduce hydrophilic carboxyl groups, and hydroxyl or epoxy groups are copolymerized with hydroxyethyl (meth)acrylate or glycidyl (meth)acrylate to further introduce acryloyl groups. For example, the following reports on the synthesis of water-soluble photocurable resins by copolymerization of acrylic monomers:

3 Water-based photoinitiator

In the structure of oil-soluble photoinitiators, anionic or cationic groups or hydrophilic nonionic groups were introduced, and water soluble photoinitiators were developed and researched. The water-soluble free radical photoinitiator can obtain good compatibility with the aqueous photocuring system, and the photoinitiator can be uniformly dispersed, which is favorable for obtaining a satisfactory polymerization and curing effect. Common water-soluble photoinitiators are mainly the following: polysilane derivatives; thioxanthone derivatives; benzophenone series; hydroxy phenyl ketone derivatives. For example, QTX and 2959 produced by Dahu Company are commercial products. Its structure is as follows:

4 Application Prospects of Water-based Photocurable Materials

To ensure the sustainable development of the ecological environment on which human beings live, green technology has become the mainstream of scientific development. It is to adapt to the mainstream of this science and technology development that water-based photo-curing systems have emerged and become extremely active research and development fields. It is expected that water-based photo-curing systems will first find application in the following areas: wood coatings, screen printing inks, resists, flexographic printing plates and inks, textile printing coatings, and various coatings. The electrodeposition photoresist used in the production of printed circuit boards (PCBs) is a water-based photo-curing material. The water developing photoimaging solder mask being developed is also a water-based UV photocurable material. The research and development of water-based UV-curable inks provide new opportunities for screen printing. It reduces the screen printing by up to 40% of the spot height, thereby considerably improving the visual effect of printed images. Another potential market for water-based UV-curable inks has been reported in the relevant magazine, which is the only UV printing ink known for textiles. Although there are still some problems to be solved. Such as the ink curing speed and the safety of clothing, but once the above problems are solved, water-based UV-curable inks will certainly become very competitive tight products.

Source: Print Chemicals Network