The products you design solve problems or make a difficult task easier. This process demonstrates the effectiveness and efficiency of your designs, but what about the visual appeal and branding of your products? This important detail cannot be overlooked and often requires printing and graphics.
So what do you do if you learn that the graphics on an existing product line are “peeling away,” or if you find the labels on your newest product line “will not stick?” For one, it is necessary to make sure your print vendor understands labels and graphics; and two, they value quality and are dedicated problem-solvers. At Galleon Innovative, we understand labels and graphics, and will provide dependable guidance and problem-solving skills necessary to best achieve your goals and objectives.
Let us look at the problem just discussed: failure to adhere.
Often, the biggest culprit for lack of adhesion centers around the Surface Energy of the Substrate the label or graphic is applied to. The higher the surface energy (High Surface Energy or HSE) of the substrate, the easier it is to stick to. The lower the surface energy (Low Surface Energy or LSE) of the substrate, the more difficult it is to stick to.
The strength of the molecular attraction (adhesion) that exists between the substrate and the adhesive is determined by the surface energy of these materials. Surface energy is measured in dyn/cm or mJ/m2. When an adhesive can flow and cover more surface area on a substrate, there will be better adhesion (high dyne per centimeter levels reflect HSE). On the other end, LSE substrates resist the flow of the adhesive because the molecular attraction is low between it and the substrate. Less surface area of the substrate is covered with the adhesive, and this makes for a likely candidate of “failure to adhere.” *
Here is a list of several Low Surface Energy (LSE) substrates and surfaces:
• Polypropylene (PP)
• Polyethylene (PE)
• Ethylene-vinyl acetate (EVA)
• Tedlar® (Polyvinyl Fluoride)
• Powder Coated Paints
If you are working with any of these substrates or surfaces, selecting the proper LSE adhesive on a label or graphic is crucial for achieving good results. LSE adhesives are specially formulated to flow better on LSE surfaces and substrates for optimum or improved adhesion.
Once the surface energy (SE) of the substrate has been determined, the following surface characteristics must be addressed. Each of these can have a significant impact on the effectiveness of adhesion.
• Surface Cleanliness: How clean and free from chemicals (oils, injection mold release agents, grease) is the surface? Contaminates can alter the Surface Energy.
• Surface Coatings: Is the surface painted or waxed? If the surface is painted, is it powder coated? Powder coated paints have Low Surface Energy.
• Surface Curvature: To what degree is the surface convex, concave, or compound? The greater the curvature, the more challenging it is to achieve good adhesion.
• Surface Finish: Is the texture smooth, wavy, or rough? Finishes can affect the amount of surface area the adhesive will come in contact with, and may require a thicker adhesive layer to achieve good adhesion.
Next, environmental factors play a critical role in determining the base material, lamination, and adhesive selection for the label or graphic. These factors can be summarized as follows:
• Temperature: What temperatures extremes, high and low, will the label be exposed to?
• Particulates: Will the label be exposed dirt or debris?
• Weather: Will the label be used outdoors and need to withstand exposure to the sun, rain, or snow?
• Solvents: Will the label be exposed to chemicals or harsh solvents?
• Durability: Will the label be prone to rubbing or considerable handling?
• Material Restrictions: Are there any hazardous materials restrictions that must be followed? For example, RoHS compliance?
Once these factors have been addressed, the remaining variable in assembling the right materials is determining the dimensional tolerances of the label or graphic. All materials, especially plastic/polymer films, expand and contract in different environments over time. Selecting the right base material, adhesive, and lamination is essential to meet these required tolerances.
So when your next project requires labels or graphics, remember that Galleon Innovative is a specialist in this field. Contact us! We will navigate you through the selection process to provide the right quality product, and you will hear the words “These labels ARE sticking.”
*3M Converter Markets Selection Guide © 2009. 3M Industrial Adhesives and Tapes Division.
