Pressure sensitive adhesives, also known as PSAs, are a type of non-reactive adhesive that forms a bond with a substrate through the application of pressure. They do not require any kind of solvent to activate their adhesive properties. There are both water-based and hot melt PSAs, but we will be focusing on the characteristics and applications of the hot melt variety in this article.
Characteristics of pressure sensitive hot melt adhesives
Pressure sensitivity
Hot melt PSAs can adhere securely to a substrate with nothing other than contact and the application of pressure. Generally speaking, the more pressure is applied, the better the adhesion will be.
Factors such as smoothness and contaminants can affect the adhesive’s ability to bond, which is why we usually smooth stickers out when placing them, and why sticky notes eventually lose their ability to adhere to surfaces.
Permanent tack
While most hot melt adhesives require elevated temperatures followed by cooling time in order to form a bond, pressure sensitive hot melt adhesives retain their ability to stick to a surface at room temperature. This is due to the fact that, unlike most adhesives, hot melt PSAs never truly set completely, but remain tacky indefinitely.
Their long open time (the time during which a bond can be made) makes hot melt PSAs ideally suited for precoating, meaning situations where the adhesive needs to remain sticky after it has been applied. For products such as sticky notes, tape and sanitary napkins, the fact that bonding can take place completely independently of the adhesive’s application is essential.
Pressure sensitive hot melt adhesives can be manufactured to create removable or permanent bonds.
Other characteristics
Other characteristics of pressure sensitive hot melt adhesives include flexibility, elasticity, the ability to bond to a wide range of substrates, and high bonding strength but lower cohesive strength.
Applications for pressure sensitive hot melt adhesives
Like other types of hot melt adhesives, the composition of hot melt PSAs can be modified to customize final properties such as surface tack, cohesion and adhesion. Furthermore, the fact that adhesion is created through pressure means that applying hot melt PSAs doesn’t require any elaborate equipment, can be easily automated and saves time because no curing is necessary. These characteristics make pressure sensitive hot melt adhesives very versatile and suitable for a wide variety of applications.
Pressure sensitive hot melt adhesives such as Thermobond JPS70300 can be used to manufacture products such as diapers and sanitary napkins, insect and rodent traps and packaging. Other applications for hot melt PSAs include labels, bookbinding, security tape and automotive and other transportation components.
Adfast: your source for high-quality adhesives
In this article, we’ve covered just a few of the applications and characteristics of this incredibly versatile, efficient and easy-to-use adhesive. If you’d like to find out more about pressure sensitive hot melt adhesives, feel free to get in touch with us! Adfast is a leading provider of high-quality, eco-friendly adhesives. Our experts will be happy to answer any questions you have and help you select the right adhesive for your needs.
