Under the brand name Bremar, Robert Kraemer GmbH & Co. KG offers polymerized gum rosin. This binder is produced using a special process, during which the resin acids of the gum rosin are dimerized. The resins are available in different polymerization degrees. The dimer portion comprises 30% to 80%. Depending on the dimer portion, polymerized gum rosin has different nominal values (melting point, acid number, viscosity/flow time), which has an effect on the application technological properties.
Contrary to unmodified gum rosin, dimer resins are characterized by their oxidation stability, crystallization stability and improved adhesion (tack). They are used as tackifiers in hot melts, solvent-based adhesives and dispersion adhesives, as binders in inks, printing inks and lacquers or in soldering pastes. Polymerized gum rosin furthermore shows a good polymer-compatibility and because it may be dissolved in water, it is also suitable for aqueous systems.