This is an interesting question that pops up from time to time. The reputation of fluoropolymers as non-stick coatings will make any curious coatings formulator ponder about the adhesion properties of LUMIFLON resins. It is important to remember that the chemical structure of the solvent-based LUMIFLON resins is such that they possess properties that are foreign to pure fluoropolymers – the ability to be dissolved in a wide range of solvents, the ability to achieve a high gloss, etc. These modifications of the resin structure will also improve its ability to adhere to a variety of substrates without the use of special primers or exotic additives in the formulation. Of course, the adhesion properties can be limited when it comes to the traditionally difficult surfaces to coat – especially hard, glossy substrates. It is always prudent to check a coating’s adhesion to any potential substrate before signing off on the formulation.
Having told that story, the water-based LUMIFLON FE emulsion products are a different story altogether. Due to the component and processing changes necessary to create stable emulsions with this type of hybrid fluoropolymer, the adhesion of these resins is compromised. In order to formulate a water-based 1K coating with adequate adhesion to metal substrates, these emulsions have to be blended with the conventional water-based emulsions (most popularly, the acrylic type) used in coatings for this market. The maximum percentage of LUMIFLON emulsion recommended as part of the total binder in the formulation is 50%.
As far as the 2K water-based LUMIFLON dispersion resin, our FD1000 product falls somewhere between the solvent-based resins and the emulsion resins. Again, it is important to check the adhesion performance during the creation of the formulations and to utilize appropriate additives to insure proper substrate wetting and proper surface tension reduction in the coating.
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