Removable pressure sensitive adhesive

Removable pressure-sensitive adhesives are used on a variety of products, including labels, tapes, membranes, etc. so that the product adheres to the substrate and can be easily removed from the substrate without leaving stains or residues. In order to be suitable for such applications, the pressure-sensitive adhesive must have good adhesion with low peel strength and must not show significant growth in adhesion over time. Ideally, the pressure-sensitive adhesive should exhibit such physical properties on a variety of substrates.

Typical commercially available water-based acrylic emulsion pressure-sensitive adhesives cannot be used for outdoor applications. An outdoor application includes a decorative decal film applied to a substrate such as glass. One technique for attaching the decorative decal film to the substrate is to spray water over the adhesive and/or substrate so that the decal film can slide over the substrate for easy positioning.

Unfortunately, in this type of technology, the water-based acrylic emulsion adhesive film turns milky white in contact with water. Another outdoor application includes a protective film applied to a construction project material using an adhesive, where the film is used to protect the structural material until the completion of the construction project. Exposure of protective film-covered building materials to water or high humidity in an outdoor environment often results in a milky white color for water-based acrylic emulsion adhesives. For transparent film surface material,

The whiteness of the water will result in an unsatisfactory appearance.

For a successful water-based acrylic emulsion removable pressure-sensitive adhesive used for decorative or protective film and decal film for outdoor applications, the adhesive will need to demonstrate good water resistance along a good anchorage of the adhesive to the membrane surface material to ensure clean removability from the substrate. The current commercial purchase of water-based acrylic emulsion pressure-sensitive adhesive showing good water whitening resistance is a permanent adhesive, that is, if the surface material is removed will leave adhesive residue on the substrate of those adhesives, the film shows good anchoring properties of the existing removable water-based acrylic emulsion pressure sensitive adhesive also shows water whitening resistance. Therefore, there is still a need for two kinds of water-based acrylic emulsion pressure-sensitive adhesives that show both removability and water-whitening resistance.