Impact strength
Polycarbonate has up to 30 times the impact strength of acrylic. Although acrylic is high impact, polycarbonate is extremely resistant to breakage. Polycarbonate is often used in bullet-resistant applications due its superior impact strength.
Weatherability
Polycarbonate may offer better panel strength and higher wind load ratings than acrylic, meaning it can withstand the forces of wind better. However, acrylic and polycarbonate can both withstand high winds and both have excellent long-term weatherability characteristics. Depending on the application and project requirements, one may be preferred over the other.
If considering signage in areas prone to hurricane-force winds, polycarbonate at 3 mm (0.118 in.) and greater is rated under Miami-Dade for use in high-velocity hurricane zones. Smaller signs of 914 mm (36 in.) or less would likely use acrylic. Where a trim cap is being used, acrylic is the preferred substrate because acrylic glues much more easily than polycarbonate.
For large signs where forming is required and there are no drying capabilities, or for formed signs requiring a higher degree of definition on the corners and edges, high-impact acrylic is recommended.
Esthetics
Contemporary signs and graphic displays are highlighted by lighting the edge of the acrylic instead of the back.
In addition to the impact resistance of IMA, another benefit of acrylic is a sleek, glossy exterior, as mentioned. The exterior shine on the finish of a high-impact acrylic lighted sign panel can be a significant selling point for business owners. Acrylic display colours are better than those seen with polycarbonate and offer better clarity in the sign design. Standard polycarbonate will yellow in exterior applications unless customers are ordering a type of polycarbonate with a co-extruded UV-blocking capped layer. This layer provides a high level of UV absorption to the polycarbonate sheet, extending weathering performance.
Design creativity and innovation
Another esthetic point to be aware of is glare and the use of edge-lit products. Edge-lit material comprised of continuous cast acrylic has illuminated particles infused throughout the sheet, forcing light out. In many instances, this is used to diffuse LED lighting. An example is retail signage using edge-lit material with a graphic on top for promotional purposes. Such illuminated signs can employ a one- or two-sided design, and may be useful in applications such as illuminated wraparound counters, exit signs, and other wayfinding/directional supports.
Another example, used by cosmetic retailers to entice customers and showcase their logos or brand names, is block lettering. These are solid sheets that can be up to 30-mm (1 1/8-in.) thick and can be used as a standalone design or as push-through letters. Many major brands use large block letters, inserting LEDs in the back of each letter without a metal outline to offer an elegant look.
For a sophisticated lighting effect, another design option is to employ continuous cast material with a frost effect incorporated throughout. This frost effect will not wash out during the fabrication or forming process and offers an elegant, soft look for displays, wall partitions, and dividers.
Conclusion
There are solid advantages to selecting cell cast, continuous cast, extruded, and high-impact acrylic, as well as polycarbonate. These plastics are exceptionally durable and will last for many years, while still maintaining their pleasing appearance. The final decision is a matter of preference, manufacturing capabilities, and what is most important in the application.
Retail signage is one of the first and last things customers see when they visit a store. It is crucial to ensure the right solution is selected for the long term. Whether employing polycarbonate or acrylic, retailers can be confident the result will be the perfect lighted sign to meet their business needs.
Jane Nash, Tennessee sales manager/specification specialist for Plaskolite, has been in the acrylic manufacturing industry for more than 40 years. She joined Plaskolite in 2018 as part of the Lucite acquisition and is actively involved with sales and specifications, working with architects and the design community. Nash is active with several organizations, including the Society of Experiential Graphic Design (SEGD), American Institute of Architects (AIA), Screen Printing and Graphic Imaging Association (SGIA), ISA, and the Mid South Sign Association (MSSA). She can be reached via e-mail at jane.nash@plaskolite.com.
Notes
1 For more information, visit nrf.com/media-center/press-releases/nrf-forecasts-retail-sales-exceed-433t-2021-vaccine-rollout-expands.
2 In 2016, an agreement was signed between the U.S. Food and Drug Administration (FDA) and Canadian Food Inspection Agency (CFIA) recognizing each other’s food safety systems as comparable to one another.
