Pigment dispersion is one of the key formulation challenges in UV inks. Whether the system is designed for UV inkjet, screen printing, flexographic printing, or offset printing, the resin must work effectively with pigments while also meeting requirements for viscosity, curing speed, adhesion, flexibility, and final film performance.
When pigment particles are not sufficiently wetted by the resin system, the resulting ink may show uneven color development, poor print definition, instability during storage, or inconsistent curing. For this reason, pigment wetting should be considered together with resin selection rather than treated as an isolated formulation issue.
A practical approach is to select a UV resin with suitable pigment wettability first, then balance the remaining performance requirements through the resin chemistry and other formulation components.
Why Resin Selection Matters for Pigment Wetting
In a UV ink formulation, the resin is more than a film-forming component. Its interaction with pigment particles can influence how easily pigments are incorporated and dispersed throughout the system.
For low-viscosity UV ink formulations, the resin must also maintain a suitable flow profile while providing sufficient pigment wetting. This becomes particularly important in inkjet applications, where viscosity and formulation stability are closely related to printing performance.
For other printing technologies, such as screen, flexographic, and offset inks, the resin may need to balance pigment wetting with adhesion, flexibility, hardness, and curing response.
This is why different resin chemistries can provide useful options for the same pigment dispersion challenge.
L-6121 and L-6211: Two Resin Approaches to Pigment Wetting
Lencolo's UV Inkjet & UV Inks portfolio includes several resin options designed around different formulation requirements. Among them, L-6121 Low Viscosity UV Polyester Resin and L-6211 Low Viscosity 2-Functional UV Polyurethane Resin are particularly relevant when good pigment wettability is required.
L-6121 is a low-viscosity UV polyester resin with good pigment wettability. Its combination of low viscosity and pigment wetting makes it suitable for formulators developing UV ink systems where consistent pigment distribution is an important consideration.
L-6211 takes a different resin approach. It is a low-viscosity, 2-functional UV polyurethane resin with good pigment wettability. The polyurethane backbone provides an alternative route for formulators who need to consider pigment dispersion together with properties such as flexibility and overall film performance.
Having both polyester-based and polyurethane-based options allows ink developers to evaluate resin chemistry according to the requirements of the complete formulation rather than relying on a single resin type for every application.
Balancing Pigment Wetting with Flexibility and Curing
Good pigment dispersion alone does not guarantee a successful UV ink. Once the pigment has been properly incorporated, the formulation still needs to achieve the required curing speed and cured-film properties.
For applications where flexibility and elasticity are important, L-6105 Low Viscosity, High Elasticity UV Polyurethane Resin provides a resin option with high flexibility.
When faster curing is a priority, L-6111 Low Viscosity UV Epoxy Acrylic Resin is positioned for fast curing performance. This type of resin can be considered when printing productivity and rapid film formation are important alongside pigment dispersion.
The appropriate balance depends on the printing process, substrate, pigment system, and final performance requirements. Resin selection therefore works best as part of a complete formulation strategy rather than as a single-property decision.
Adhesion Across Different Printing Substrates
Substrate compatibility is another important factor when developing UV inks. An ink that disperses pigments well but fails to adhere to the target substrate will not provide a reliable finished result.
Lencolo offers several UV resin options for different substrate requirements. L-8400A/8400B is a UV resin for glass and hardware with good adhesion. L-6030/6040, a UV pure acrylic resin, provides another option for UV ink formulations where adhesion is important.
For flexible film applications, L-8412A UV Polyurethane Resin for PET combines UV resin technology with high flexibility for PET substrates.
These different resin options illustrate an important principle in UV ink development: pigment wetting, viscosity, flexibility, curing, and adhesion should be evaluated as interconnected formulation requirements.
A Broader UV Ink Material Platform
Guangdong Lencolo New Material Co., Ltd., operating under the Lencolo brand, develops UV-curable materials and formulation solutions for a range of applications. Its product portfolio covers UV resins, reactive monomers, photoinitiators, functional additives, and finished or semi-finished UV products.
For UV ink developers, this broader material platform provides access to resin technologies for UV inkjet, screen printing, flexographic ink, and offset ink applications. The company also provides formulation support and technical assistance, allowing resin selection to be considered alongside other components of the UV ink system.
The Lencolo application guide identifies its UV Inkjet & UV Inks portfolio around several core requirements, including pigment wetting, adhesion, flexibility, and fast curing. This application-oriented approach is useful for formulators who need to move beyond simply comparing resin names or chemical categories.
Building a More Stable UV Ink Formulation
Pigment dispersion is best addressed as part of the overall UV ink formulation. A resin with good pigment wettability can provide a strong starting point, but the final formulation must still balance viscosity, curing speed, flexibility, adhesion, and substrate compatibility.
For this reason, L-6121 and L-6211 provide two different resin routes for formulations where pigment wetting is a priority, while L-6105, L-6111, L-8400A/8400B, L-6030/6040, and L-8412A offer additional options for flexibility, curing, and substrate adhesion.
For ink manufacturers and formulators evaluating UV materials, selecting the resin according to the actual printing process, pigment system, substrate, and performance target can make the development process more structured and efficient. Lencolo's broader UV material portfolio provides a foundation for this application-driven approach, covering both individual raw materials and formulation-oriented UV solutions.
https://www.lencolo37.com/
Guangdong Lencolo New Material Co., Ltd.
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