WACKER Unveils Polymer Resin Binder with Enhanced Solubility for Use in Printing Inks, High-Solids and UV-Curing Systems at European Coatings Show 2023

25 February 2023: At 2023 European Coatings Show (28-30 March 2023 at Nuremberg, Germany), WACKER will be unveiling a new product from its VINNOL® family of solid resins: VINNOL® L-6868 binder is suit-able for solvent-borne coatings, printing inks, high-solids and UV-curing systems. It can also be used to formulate wood, paper and film coatings. New polymer resin has the lowest viscosity within the VINNOL® family. In addition, VINNOL® L-6868 is compatible with a wide range of UV monomers and reactive diluents. The product’s most notable characteristic is its very good solubility in all kinds of solvents.

The binder is the film-forming component of any printing ink or coat-ing. It encloses the pigment particles, bonds them together and to the substrate. Through its VINNOL® portfolio of products, WACKER already offers an extensive range of polymer resins that perform this very task in many application areas.

As innovative technologies and new processes emerge, the require-ments of the printing inks and coatings industry keep changing. For this reason, the company works continuously on developing its VINNOL® resins. Its latest development: VINNOL® L-6868. This polymer resin represents the optimal expansion to the product port-folio offered by WACKER, because it is an even better additive than the other polymer resins that are already available for UV-curing printing ink systems.

Development of the product started with VINNOL® H 40/43, an exist-ing polymer resin grade. This is a copolymer of vinyl chloride and vinyl acetate that has no functional groups and is suitable for a wide range of solvents and UV monomers. Overall, it has the best solubil-ity and, up to now, offered the lowest viscosity. However, several potential customers expressed a wish that its properties be improved even further.

To achieve this, WACKER experts modified its molecular composi-tion. They minimized the copolymerized vinyl chloride content to 44 percent and maximized the vinyl acetate content to 56 percent. The outcome is a decisive improvement in solubility that renders VINNOL® L-6868 highly soluble in ketones as well as in esters, acrylic monomers, UV monomers and glycol esters. At the same time, the lowering of the vinyl chloride content, which provides toughness and hardness in the polymer as well as chemical resistance of the coating, improves the processing properties of formulations.

The combination of modified polymer composition and very low molecular weight has the effect of substantially lowering the viscosity of the polymer resin. In a 20-% methyl ethyl ketone solution at 20 °C, the viscosity of VINNOL® L-6868 is just 7 mPa*s. By comparison, the corresponding value for VINNOL® H 40/43 is 25 mPa*s. Even so, the new binder can be used to formulate high-solids systems, i.e. those with high pigment and binder contents. VINNOL® L-6868 is also suitable for reactive curing systems.

Due to its very low molecular weight, VINNOL® L-6868 represents the optimal solution for formulators addressing challenges relating to flow, intercoat adhesion, and flexibility in UV-curing systems. Appli-cations for the new binder include printing inks, plastic coatings, wood coatings, paper and film coatings. VINNOL® L-6868 can also be used to formulate coatings for food-contact packaging.

Visit WACKER at the European Coatings Show 2023 in Hall 1, Booth 1-206.

www.wacker.com/ecs.