UV-curable coating formulations have complexity, as follows:

　　First, a variety of monomers, the base oligomer (resin) types are currently synthesized according to the functional groups to be divided into unsaturated polyester PE, epoxy EA, polyurethane PUA, polyester PEA, amino, polyether, silicone, phosphate, mixed classes, etc..

　　Second, according to the function of UV-curable coatings commonly used in the resin has the following categories:

　　1, hard resins - Tg high, high hardness, good chemical properties, most fast curing. Such as standard bisphenol A EA; high-functional PUA and small molecular weight 2fPUA; high-functional amino acrylate; methacrylate oligomer.

　　2, soft resin - Tg small, flexible, slow curing speed, low crosslinking density. Such as modified epoxy - epoxy soybean oil acrylate, etc.; long-chain polyester acrylate; straight-chain structure of the average molecular weight of more than 1200 PUA; part of the pure acrylate oligomer.

　　3, polar resin, is containing active hydrogen or easy to form hydrogen bonds oligomer, can change the polarity or surface tension. Such as phosphate acrylate; silicone oligomer; carboxy acrylate oligomer, etc..

　　4, water-based UV oligomers, common emulsion-type, water-dispersed, water-soluble type

　　5, non-crosslinking resins in the UV-curable coatings formulations have a filling effect, improve crosslinking density, increase adhesion, change flexibility, enhance wettability and other roles. Common such resins are long oil alkyd resin; thermoplastic acrylate resin; aldehydes and ketones resins; petroleum resins.

　　Third, the design of UV curing (UV) coating formulations resin selection before the design of coating formulations, should be clear coating type, that is, the primer, topcoat or paint; and understand the basic properties of the material being coated, such as the size of the polarity (surface tension), the presence or absence of crystallization, belonging to the thermoplastic or thermosetting and so on. Specific description is as follows:

　　1, the choice of primer resin: first of all, the requirements of adhesion, which is the generality of the primer resin; wettability, refers to the pigment, filler wetting and wetting of the substrate, which are two different requirements, because the substrate surface tension and pigment and filler will not be exactly the same; flexibility, mainly related to sanding and interlayer adhesion.

　　2, top coat resin selection, top coat need to achieve the performance and for the selection of resin is described below:

　　Film fullness and leveling: to achieve this requirement, you need to choose a good compatibility with the resin and monomer, improve the wetting and leveling with the primer, crosslinking degree is appropriate to improve the selection of higher refractive index of the resin;

　　Toughness: mainly related to hardness and abrasion resistance. These two properties are related, but not necessarily identical, need to be treated differently.

　　Interlayer adhesion: the solution of interlayer adhesion needs to meet the wetting leveling and resin polarity with.

　　Chemical resistance and yellowing resistance: EA, PUA (polyester) has good chemical resistance, PE, polyether is worse; generally believe that aliphatic PUA, pure polyether acrylate, pure propylene, amine class have good yellowing resistance, formula to add the right anti-yellowing agent can also be effective in enhancing the yellowing resistance of the topcoat.

Matting requirements: some resins with small or large molecular weight will have certain matting effect; some polyurethane resins also have good matting effect.

Please feel free to ask us about our light-curing resins, which can meet your needs.