1K latent reactive adhesive systems offer the advantages of a 2K system - bond strength, heat resistance and durability
High initial and final bond strength, good heat resistance and long-term durability – these typical 2K benefits are available in 1K adhesives thanks to latent-reactive technology. These 1K adhesives based on a Dispercoll® U polyurethane dispersion not only offer excellent adhesion properties but are also easy to handle with no need for pre-processing dosing and no pot-life worries.
Latent-reactive adhesives are composed of a semicrystalline polyurethane polymer (PUR) into which solid surface-deactivated polyisocyanate particles are embedded. The PU polymer only melts when the adhesive is heated to more than 45° C when crosslinking begins. As the adhesive cools down, the PUR polymer crystallizes and quickly achieves high bond strength.
Advantages of latent-reactive adhesives
With only one component the logistics of transportation and storage are much simpler. Since no component has to be applied before application, the risk of human error is virtually eradicated. Only relatively brief heat activation at relatively low temperatures and pressure is required to achieve a strong adhesive bond. No pot life means much more flexibility in applying latent reactive adhesives. And the outstanding adhesive properties include high final bond strength, resistance to oils, fats and plasticizers, and excellent temperature resistance.
Three application possibilities
The Dispercoll® U product range covers three application areas: as a latent-reactive polyurethane dispersion with no need for an added crosslinker; as a substrate pre-coating with a storage-stable, latent-reactive adhesive film for separate drying and adhesion processes; and as a latent-reactive hot-melt adhesive film. The Dispercoll® U grades mainly differ in their polymer softening characteristics. The standard grades Dispercoll® U 53 and Dispercoll® U 54 are suitable for most heat-activated applications; Dispercoll® U 56 is ideal for low application temperatures; and Dispercoll® U XP 2578 combines the properties of the standard grades with the option to formulate 1K adhesive systems, e.g. in combination with Dispercoll® BL XP 2514. Whatever your needs, we can supply you with the right raw materials for a high-performance latent-reactive adhesive.
For a face-to-face discussion of your individual questions and needs please get in touch with your regular contact persons at our distribution partners or at our local agents.
