HSE & LSE Substrates Identification

Identifying Substrates and Pairing the Right Adhesive

When searching for the appropriate adhesive system to create the best bond to your substrate, most important to consider is surface condition. Features such as roughness, smoothness, how porous, coated, uncoated, cleanliness, flexibility and size of the part. However, one of the most critical issues to determine is surface energy of the substrate. You must identify the surface energy as either HSE or LSE. Most substrates are classified as either High Surface Energy (HSE) or Low Surface Energy (LSE) and are categorized by their dyne levels.

To understand the concept of surface energy, simply, if you have a substrate with a slippery, heavily coated surface, adhesives have a difficult time flowing into that substrate, therefore not creating a solid bond. These substrates are considered Low Surface Energy or LSE.

If you have a non-coated, clean, or coarse surface the adhesive can flow into that substrate, therefore creating a solid bond. These substrates are considered to be High Surface Energy or HSE.

The surface attraction between diverse materials is referred to as adhesive bond. The bond of the adhesion to the substrate is determined by the surface energy of the material. The higher the surface energy, the stronger the bond and lower the surface energy, the weaker the bond. If the substrate is classified as an HSE or a High Surface Energy surface, you can use solvent based acrylic adhesive systems for bonding. If the substrate is classified as LSE or a Low Surface Energy surface you can use modified solvent acrylic, rubber and/or silicone adhesive systems.

EXAMPLES OF SUBSTRATE TYPES

HSE substrates allow an adhesive to “wet out”, which elevates the bond. Some HSE substrates include; PET, ABS, Polycarbonate, Rigid PVC, Uncoated Papers, Acrylic, Nylon, Epoxy Paint, Polyurethane, Copper, Aluminum, Zinc, Tin, Lead, Stainless Steel, and Glass.

LSE substrates fight the adhesive and will not allow an adhesive to “wet out”, which decreases the bond. Some LSE substrates include; PVA, Polystyrene, Acetal, EVA, Tedlar, Silicone, Wood, Cement, Nylon, Polyester Fabric, Polyethylene, Polypropylene, PVF, PTFE, Powder Paint, Acetal, Coated Papers, Carpet and Flooring underlayment.

Similar to water, adhesive on a high surface energy surface flows and “wets out” the surface. Adhesives that do not wet a surface will not fill surface irregularities, making bonding a challenge. “Wetting out” is required to form a strong bond.

Non-Wetting

Wetting

Perfect Wetting

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QUICK ADHESIVE REFERENCE

While one of the biggest advantages of adhesives is the ability to bond dissimilar substrates together, it’s important to find the RIGHT adhesive to do so. You must consider the material, application, and environmental variables, like temperature tolerance or chemical resistance.

Solvent-Acrylic Adhesive Characteristics

Superior adhesion to HSE & some LSE surfaces, excellent aging and UV resistance, humidity and moisture resistant, chemical and oil resistant, durable heat (350F Long Term/450F Short Term) and cold temperature (-25F) range, visual clarity, permanent adhesive bond to many films, metals, plastics and glass.

Silicone Adhesive Characteristics

Superior adhesion to LSE surfaces, excellent aging and UV resistance, humidity and moisture resistant, chemical and oil resistant, widest heat (500F) and cold temperature (-30F) range, clean removability, great electrical insulation properties, exceptional adherence to silicone coatings, silicone rubber/sponge and fluoroelastomers.

Modified Solvent-Acrylic Adhesive Characteristics

Superior adhesion to HSE & some LSE surfaces, excellent aging and UV resistance, humidity & moisture resistant, chemical & oil resistant, durable heat (350F Long Term/450F Short Term) & cold temperature (-25F) range, visual clarity, permanent adhesive bond to many films, metals, plastics and glass.

Rubber Adhesive Characteristics

Superior adhesion to LSE surfaces, excellent “wet-grab”, good moisture resistance, mild chemical resistance, low temperature resistance from 25F to 150F, permanent adhesive bond in temporary applications, and good conformability.

ELITE TAPES USED FOR HSE & LSE SUBSTRATES

Elite Tape’s Technical Support Team is ready to help by providing any additional information and options. Our technical expertise, customer support, converting capabilities and fast turnaround put us in a unique position to address your most challenging application requirements.

At Elite Tape, “We Make It Easy.”