What Is a Release Coating?
Release coatings are applied to surfaces such as paper, plastic, and other films to produce a nonstick surface. The nonstick surface provided by these coatings permits adhesives and other sticky materials to be released from the surface more easily. Silicone release coatings are the most common type of release coatings used today, though other chemistries besides silicone, such as PTFE and polyurethane, are also used.
Where Are Release Coatings Used?
When tapes and labels are manufactured, release coatings are typically applied to release liners or the reverse side of the adhesive substrate to prevent dust and dirt from accumulating on the adhesive. These release coatings also allow pressure-sensitive adhesives to be easily released from the backing material without impacting the adhesive performance.
While release coatings are primarily used in the manufacture of backing materials for tapes and labels, their utility extends to any application where unintentional adhesion is detrimental. In food packaging, for example, release coatings are used to prevent sticky foods from aggressively adhering to the inside of a package.
SilForce™ UV-Curable Release Coatings
SilForce™ is a line of UV-curable silicone release coatings composed of silicone base polymers, photoinitiators, and release modifiers. These three components are blended and adjusted to allow for fully customizable release performance. Once cured, the silicone release coating may accept pressure-sensitive adhesives made of acrylic, rubber, and other adhesives not made using silicone. Unlike release coatings cured through heat, the UV cure properties of SilForce™ comply with environmental and safety requirements.
SilForce™ is ideal for coating several paper substrates, such as kraft, glassine, and machine-glazed paper. SilForce™ is also well suited for coating film substrates, including polyethylene, polypropylene, polyester, and polystyrene.
SilForce™ UV-curable release coating systems offer the following benefits:
Cures with atmospheric conditions, with no nitrogen required
Customized release properties and performance
Developed for multiroll coating processes
Flexibility with cure rate, performance, and release properties
Formulating a UV-Curable Release Coating with SilForce™
As mentioned above, SilForce™ release coatings offer excellent formulation flexibility and can be easily customized based on desired release properties. To begin, a silicone base polymer that provides the proper release force for the intended pressure-sensitive adhesive (PSA) should be selected.