Water flexible version (below)

(1) Core-shell structure water developing flexographic plate. The core is a polymerized, cross-linked rubber particle (ball), &=1um; the shell is an anionic outer layer with a carboxyl group or a phosphate group; the continuous phase is a quaternary ammonium ion acrylic monomer or other polymerizable cross-linkable substance .
(2) Polyether-amino acid ester: Polyether-diisocyanate + alkoxy product of trimethylolpropane-HDI-HEMA.
(3) Polyether-polyester block copolymers.
(4) A system mainly composed of an acrylate copolymerized elastomer.
(5) Saponification system of ethylene-vinyl acetate copolymer.
Fourth, the core-shell structure or core-shell structure flexible system of water systems is the hot spot in the development of the current hot plate. The inventor is DuPont, and the Japanese paint company is also developing and launching the product.
1. Composition of a water-based flexographic plate of a core-shell structure (1) Core-shell: Emulsion polymerization Cross-linked elastomer ions are used as the inner core (usually a rubbery elastomer), and monomers or oligomers containing active double bonds are copolymerized on the surface of the core. Carboxyl anion can be formed;
(2) Acrylic monomers containing a tertiary amine (tertiary amine) group accept carboxyl hydrogen ions on the shell to form a quaternary ammonium salt cation, which is compatible with the core and shell, and is water soluble;
(3) As a continuous phase, a rubber-based polymer that acts as a combination;
(4) Photoinitiators and Thermal Inhibitors.
The shelled or shellless solid-state flexographic plates designed around the core-shell structure are listed in Table 2. Their common characteristics are: before curing (before cross-linking) it is water flushable, once cured, it has strong water resistance, and some compositions can even reach the comprehensive performance index of commonly used solvent-developing flexographic plates.
2. The composition of a polyurethane-based aqueous flexographic plate (1) The dipropylene or triol propoxylation product is modified by a second mentor cyanate ester and HEMA or HEA to obtain a polyether polyurethane acrylate, which accounts for 20-50%;
(2) polyether-polyester block copolymer polyester or polyurethane film forming solid village fat, accounting for 50-70%;
(3) The photoinitiator accounts for 2-5%;
(4) Thermal cloudy additives and related additives.
3. Composition of ethylene-vinyl acetate-based aqueous flexo (1) Film-forming elastic polymer: 10-40% ethylene and 60-90% vinyl acetate copolymer (water-insoluble) saponified to give ethylene-vinyl alcohol copolymerization Body (water soluble, 50-100% saponification);
(2) Monomer: Polyethylene glycol (meth)acrylate, HEMA, HEA;
(3) Photoinitiators: water soluble or hydrophilic photoinitiators;
(4) Thermal polymerization inhibitors and other additives.
Beijing Puming Flexographic Technology Institute has made innovative development work on this system and has been officially industrialized.
4, the composition of water-soluble nylon flexo (1) polyether diamine amide flexible elastic water-soluble nylon: 60-80%;
(2) water-soluble or water-dispersible photocrosslinking monomer: 20-40%;
(3) Water-based photoinitiation system: 2-5%;
(4) Traces of thermal retardants and additives.
In the above water-based flexographic plates, the post-tritium aqueous flexographic plate has good water solubility, and the water developing speed is fast, but the water resistance of the cured plate is still an intractable problem. Although a lot of research work has been done on this, there are not many things that are produced as a result. The products of the domestic Beijing Puming Flexographic Technology Research Institute also encountered problems, but took some measures to net-polymerize [ethylene-vinyl acetate] modified copolymers for use in flexo and commercialization, which is very attractive.
V. Problems to be Solved in Flexibility of Water System 1. The cured plate has high water absorption, ink affinity, and poor water-resistance. Ethylene-vinyl alcohols, water-soluble nylon elastomers, and water-soluble polyether-polyester block copolymers all have high water absorption. If aqueous inks are used, the plate-covering process is necessary. Water-soluble spearminal Secondly, the water resistance of core-shell aqueous systems is nearer that of ordinary flexographic plates.
2, in the excellent water system photoinitiator system and monomers, oligomers on the choice but also work.
3. The reproducibility of the resolution of the printing plate is still difficult to compare with the ordinary flexo or CTP flexo plate, especially the water-based flexographic plate after the water repellent treatment. Generally, the resolving power is reduced more or less.
4. The applicability of the extrusion calendering process still remains to be solved.
5. The balance between flexibility, elasticity and hardness is still a problem to be solved in the future. Core-shell structures or similar structures are better.