Hydroxy Acrylic Matting Resin

HYPOMER® MT 2550K - Hydroxy Acrylic Matting Resin Introduction HYPOMER® MT 2550K is a proprietary liquid matting resin based on hydroxy acrylic that provides excellent matting effect after drying without the addition of any supplementary matting agents. HYPOMER® MT 2550K has low odor and does not contain aromatic substances. The dry films of the resins are characterized by excellent transparency, smoothness and tactile or touch feel. As shown in Figure 1, HYPOMER® MT 2550K adopts a special polymerization reaction and process that combines insoluble acrylic particles with liquid resin through a bridging mechanism. Due to good hydrophilic and hydrophobic balance, solid particles are uniformly dispersed and suspended in the liquid resin to form an opaque white liquid. HYPOMER® MT 2550K has good adhesion properties on ABS, ABS/PC and other plastic surfaces. It also has good compatibility with conventional hydroxy acrylic resins. As a result, resin combinations of HYPOMER® MT 2550K and other compatible cross-linking functional OH resins (acrylic, PU, etc.); depending on the ratio, offer an excellent performance range from semi-matte to matte transparent, solid color and metallic surfaces.

Matting Theory

After coating, solvent evaporation and subsequent cross-linking reaction of the matting resin with the curing agent causes volume shrinkage and exudation of solid particles from the hardened film. As shown in Figure 2, the exuded particles cause light scattering on the film surface; thereby creating a matte effect. Unlike inorganic silica matting agents, solid acrylic particles have lower density. Thus they are more evenly distributed within the coating film, which provides more uniform matting effect over a wide range of dry film thickness. Furthermore, due to the organic nature of the solid particles, cured films have better transparency and touch feel. When matte varnishes are formulated according to similar gloss levels, as shown in Figure 3, HYPOMER® MT 2550K provides significantly better clarity/transparency compared to conventional systems containing silica matting agents. This is particularly evident when coatings are applied over PET film. Another important advantage of HYPOMER® MT 2550K is that it demonstrates gloss consistency over a wide range of dry film thickness in spray application, compared to conventional matte coatings formulated on silica basis. As shown in Figure 4, in the conventional system, a noticeably higher gloss level is observed at high dry film thickness due to settling of the matting agent. HYPOMER® MT 2550K-based matte coatings provide superior scratch resistance. This effect of HYPOMER® MT 2550K when compared with a conventional, silica-based matte varnish is shown in Figure 5. As can be seen, scratch marks are barely visible with HYPOMER® MT 2550K, whereas in the conventional coating there are distinct scratch marks. This performance advantage of HYPOMER® MT 2550K means it provides better smoothness properties compared to conventional matte coating systems. Other notable benefits provided by HYPOMER® MT 2550K are the chemical and scratch resistance of the resulting coating film. As shown in Figure 6, the chemical resistance of the coating formulated with HYPOMER® MT 2550K can be rated as excellent. Particularly, alkali stability is superior compared to coatings formulated with standard silica-based matting agents. No changes were observed in other test segments.

Conclusion

HYPOMER® MT 2550K is a unique, high-performance resin and excellent formulation tool for aqueous, matte and semi-matte transparent, pigmented and metallic surfaces. Matte coatings formulated with HYPOMER® MT 2550K combine excellent film transparency, gloss consistency, scratch resistance and tactile properties and are superior to conventional matte coatings based on silica matting agent. Coatings for automotive interior and exterior, automotive repair paints, industrial and decorative coatings, plastic components and inks can be used in various industrial applications.

Experimental

Test system: Non-aqueous, 2K, PU coating. Gloss measured using Byk Gardner Haze/gloss.

Chemical Resistance Test Procedure

• Gauze wetted with acid, alkali, perspiration, tea, coffee and water solutions is applied to Hypomer MT-2550K film. • Test duration: 120 minutes • Evaluate the surface immediately. Author Udo Schonhoff Technical Sales Manager – Coatings EMEIA Elementis GmbH Compiled by Çise Karamehmetoğlu Sales Manager Fuchs Kimya A.Ş. Compiled by Fırat Pınar Sales Manager Fuchs Kimya A.Ş.