Image of several adhesive products available from 3M - spray adhesives, hot melt, tapes and adhesive sealants.

Adhesive Formats and the 3M Adhesive Bonding Continuum

Since the invention of the first adhesive using birch bark tar, the fundamental principle of adhesion remains the same: use of a flowable raw material to hold two substrates together. Today, advances in naturally derived and synthetic materials have resulted in two common formats for the creation of industrial adhesive products. The most common types of industrial adhesives are liquid adhesives and tapes.

Liquid Adhesives

By a physical change or chemical reaction, a liquid adhesive applied between two substrates forms a solid material that bonds the substrates together. Liquid adhesives are available in several formats, providing manufacturers with opportunities to offer customers a liquid adhesive to meet various specifications.

  • In a two-part reactive adhesive, Component A is mixed with Component B; the resulting chemical reaction provides the final bond.

  • One-part reactive adhesives contain a single component that chemically reacts, most commonly when exposed to heat, light or moisture.

  • Hot melt adhesives are solid at room temperature, but applied as a melted liquid. When the adhesive returns to room temperature it re-solidifies, creating a bond.

  • Reactive hot melts are unique adhesives with the properties of both hot melts and reactive one-part adhesives.

  • Solvent- and water-based adhesives use a liquid carrier (solvent or water) to apply the adhesive to the substrates. The carrier evaporates and the adhesive remains. Common delivery methods include tubes, pails and aerosol cans.

Adhesive Tapes

Tapes are pressure sensitive adhesives or “PSAs” and they provide a value-added solution for a customer because the supplier, reacts the raw materials in advance. The customer is provided with a fully cured material with the viscoelastic properties necessary to hold two materials together, often through the use of pressure.

  • A layer of pressure sensitive adhesive is paired with a release liner. These are also available as “double-liner”, with a liner on both sides.

  • Pressure sensitive adhesive is laminated on either side of a film carrier. This allows the tape to have different functionality on the A and B sides.

  • Pressure sensitive adhesive is laminated with a pressure sensitive adhesive on either side of a foam carrier (e.g. acrylic, urethane, polyethylene). This allows the tape to have different functionality on the A and B sides, plus the foam provides unique gap-filling or elastomeric properties.

  • Pressure sensitive adhesive is laminated to a mechanically locking system with a liner.

Adhesives and Tapes Bonding Continuum

An endless variety of design requirements has led to the development of a wide variety of adhesive and tape products and formats. This broad range is represented in the spectrum of bonding technologies known at 3M as the adhesive and tapes bonding continuum. This continuum of adhesives and tapes ranges from removable pressure sensitive adhesives similar to that seen on Post-It® Notes, to high-strength curing epoxies used to bond components of airplanes.

Image of broad range of adhesive formats and capabilities in the 3M adhesive bonding continuum.