With latent-reactive dispersion adhesives a one-component formulation of an adhesive dispersion becomes possible while at the same time the properties of a crosslinking two-component system can be obtained. Latent-reactive dispersion adhesives consist of a polyurethane dispersion of a Dispercoll® U type in combination with a deactivated solid isocyanate. The deactivated solid isocyanate reacts with the dispersion polymer only after activation of the adhesive film by temperature.
This techology makes it possible to formulate in three ways:
Application as latent-reactive polyurethane dispersion This eliminates the addition of a crosslinker.
Application as a pre-coating of a substrate with a storage stable latent-reactive adhesive film Substrates can be coated with a storage stable reactive adhesive film. The process of the film-application and the adhesion itself can be separated in time and location. This makes it possible to streamline processes and make them more effective.
Application of a latent-reactive adhesive film In cases where the substrate can not be furnished with a latent-reactive adhesive coating the solution can be a block-free adhesive film. This film can either be pre-laminated on the substrate or directly applied as a block-free film between the substrates to be joined.
The Dispercoll® U product range for one-component latent-reactive polyurethane dispersions:
For latent-reactive dispersion adhesives (in combination with deactivated TDI dimer formulations, e.g. Dispercoll® BL XP 2514), considerably reduced release of TDI from the latent reactive films
Have a look at this detailed information on dispersions for latent-reactive adhesives:
