Sealant articles and compositions useful therein

Abstract

A sealant article useful for sealing a substrate surface having a first surface and a second surface is provided. The first surface comprises a deformable composition that is capable of conforming to a substrate surface when subjected to heat and / or pressure. The second surface of the sealant article has been at least partially cured by exposing said surface to an amount of radiation effective to induce at least partial curing of the second surface of the sealant article. Prior to such curing, the second surface also is comprised of the deformable composition. Such at least partial curing is effective to render the second surface less deformable than the first surface.

Description

FIELD OF THE INVENTION[0001]This invention pertains to sealant articles useful for sealing and protecting joints and the like, wherein the sealant articles are prepared using deformable compositions capable of being radiation cured to provide a deformation-resistant and constraining outer surface.DISCUSSION OF THE RELATED ART[0002]Sealants currently are employed in a wide variety of industrial applications. For example, the automotive industry utilizes sealants between and upon metal seams and welds. One specific sealant application involves the use of a sealant upon the welds in the so-called roof ditches which are formed when joining the side panels of a vehicle body to the roof of the vehicle. Conventionally, the roof ditch weld is covered with a bead or strip of a plastic (e.g., PVC) molding that is covered with a metal strip and painted. In recent years, alternative approaches have been proposed. For example, U.S. Pat. No. 6,030,701 describes sealant articles comprising a melt-...

AI Technical Summary

Benefits of technology

The solution provides a deformation-resistant outer surface that prevents blow-through and maintains a smooth, aesthetically pleasing appearance while ensuring effective sealing and bonding on uneven substrate surfaces.

Problems solved by technology

In many cases, sealing a substrate surface, especially the substrate surfaces typically encountered in vehicle manufacture, is quite challenging since a variety of different requirements must be simultaneously met.

For example, welded metal joints such as those commonly present in vehicle roof ditches often are quite uneven, due to weld dimples, projections resulting from the design of the parts being joined by welding, and so forth.

However, these characteristics also result in the outer surface of the sealant or mastic being highly susceptible to deformation due to trapped air, irregularities or projections in the substrate surface, or external forces.

In some cases, blow-through of the sealant or mastic may occur, which severely compromises the effectiveness and appearance of the seal that is sought to be achieved.

As a result, it is often difficult to provide and maintain a smooth, even, and cosmetically attractive top surface once the sealant or mastic has been applied to the substrate surface.

However, using a less easily deformable sealant or mastic composition would interfere with the ability to effectively seal the substrate surface.