Enameling Technology

Ecologically sound, resource-efficient UV paints for 3D objects

The project's result is the development of technology for surface coating or finishing of 3D objects. The project aims to make ecologically sound, ultraviolet(UV)-hardening varnishes and paints usable at an industrial scale. The goal is to improve even further the already ecologically sound, resource-saving UV hardening in regard to expenditure of materials and energy. 

 

Summary

Coating materials such as varnishes and paints not only perform a protection function for the surface they cover (e.g. corrosion protection, wear protection) but also lend the product the desired look (e.g. shine, colour). However, conventional surface finishing and coating technology utilises coating materials that contain solvents and that require a high amount of energy and time for application. The project therefore aimed to develop a new ultraviolet (UV) technology consisting of UV varnishes and paints and a UV unit. The high production efficiency and substantial environmental compatibility is intended to provide a basis for persistent change in industrial painting of series-production parts. In particular, solvent-based or aqueous enamels used in mass production are to be replaced by ecologically sound UV-hardening varnish and paint systems. The ecologically and economically beneficial system solution resulting from the research avoids VOC emissions (volatile organic compounds) and offers substantial energy savings, high profitability and efficient production.

Results:

  • The newly developed UV paints with 100% solids fulfil, at a dry layer thickness of 40 µm, the requirements of the 240-h salt spray test and the 240-h condensation-water atmosphere test; use of these UV paints represents a substantial reduction of environmental strain.
  • The use of epoxy acrylate resin in UV paint on iron-phosphate substrates achieves the same values for VDA thermal shock resistance (corrosion test) as for the current zinc phosphate substrates; this equates to a minimisation or avoidance of zinc-contaminated waste.
  • In combination with suitable reactive thinners and other binders, an adhesive resin displayed very good adhesion properties in conjunction with pigmented UV paints.
  • As raw material suitable for a binder that produces sufficient flexibility, only urethane acrylate in the form of T-Bend-Test-1 qualified.
  • In the field of aqueous UV soft-feel varnishes, which lend plastics a high-quality look, isocyanate significantly improved resistance to chemicals and substrate adhesion.
  • Use of nitrogen for inert-gas paint hardening is preferred for reasons of quality and safety. It also facilitates matting.
  • The development of a 3D UV unit results in a substantially more energy-efficient solution that can be integrated with greater flexibility into industrial processes for linking ecologically sound UV paints and varnishes with complex 3D objects.
  • The scratch-proof and solvent-free UV clear lacquers developed as transparent plastic undercoats also display an "easy-to-clean" effect.

More Project Informations

Project title:  Verbundprojekt: Dekorative und kratzfeste UV-Lackschichten mit reduzierter Schichtdicke (UV-Deko)

Project number:  01RC0001A, 01RC0003A, 01RC0409

Project period:  2004 - 2007

Project region:  Germany (Berlin, Baden-Württemberg)

Project contact:

Herr Dr. Pietschmann

This email address is being protected from spambots. You need JavaScript enabled to view it.

++ 49/391/6090-240

++ 49/391/6090-217

View Publication

Source: German National Library of Science and Technology Hannover (TIB)