signchef

Polycarbonates and Acrylics

​Ryan N. Fugler is a former editor of WRAPS magazine. 
 

Look around, you’ll find that you interact with more plastic components than you probably realized. Your phone, your keyboard, your garage door opener, television, pens, water bottles, and on and on. The great part about plastic materials is that they work across a multitude of applications—even those that aren’t at the front of your mind. They are highly conformable, which makes them able to take the shape of nearly any intended design. They are relatively inexpensive when compared to other alternatives. They have a reliable level of durability. And they work well in concert with other materials and components.

What does this mean in the sign world? Well, quite a bit. For starters, plastics provide another option to sign makers that want an alternative to metal, wood or other common substrates -- an outlet to give customers variety. Additionally, there are choices within the plastics family that can add to the brilliance of a sign project.

 

Characteristics

Polycarbonate and acrylic materials are widely used in the sign world. And both are comparatively different when it comes to their characteristics.

“Acrylic typically offers a broader color palate,” says Cindy Race, marketing/communications at Covestro. “Polycarbonate is available in most colors, but sometimes requires a large minimum order quantity. Both polycarbonate and acrylic can be can be direct-printed. Digital printing is replacing many traditional decorating methods including painting and silk-screening. Both products are compatible with first surface vinyl decoration, but thermoforming with applied vinyl can be a little trickier with polycarbonate.”

So, obviously, for sign makers there are considerations to ponder when selecting the best plastic substrate to use in a project. And the decision should not be taken lightly.

“Polycarbonates tend to be stronger and more impact resistant than acrylics,” says Matt Buckley, business development manager with GPA Specialty Substrate Solutions, “whereas acrylics are usually less expensive than polycarbonates, but can be scratched more easily.”

But each have strengths when it comes to implementing them in a sign project.

 

Sign Makers' Needs

Many of the reasons why sign makers choose to use plastic products in their jobs can be broken down into distinct categories. A few of those are the listed here with some insight provided by seasoned manufacturers.

Lifespan—It’s important for sign professionals to have an idea of how long their sign materials will last in each project. Many factors can go into how signage will hold up in different circumstances. Is it an outdoor sign facing tough weather conditions? Is it located in a place that is subject to vandalism? Does it contain elements that may cause failure?

“General purpose acrylic has a long lifespan due to its excellent resistance to UV damage, acrylic is prone to breakage, however,” says Race. “Co-extruded polycarbonate sheet can be expected to last 10 years without significant yellowing and is virtually unbreakable.”

In addition, polycarbonate offers greater heat resistance than acrylics, and has a higher impact strength with increased resistance to breakage. These traits of both polycarbonates and acrylics will contribute to the life expectancy of the overall sign. 

“The expected lifespan varies depending on the type of plastic being used and the conditions it is being used in,” says Buckley. “To achieve the best results and the longest life span, it’s important to select the right plastic for the specific needs of each project. Considerations like end-use environment, weight, and durability will help drive that decision.”

Price—Sign businesses want to make money; that’s not a secret. But being able to provide the best end-product without overspending is a very attractive option. Plastics in sign projects allow a shop to price jobs competitively.

“Historically, polycarbonate has been priced significantly higher than both GP Acrylic and Impact Modified Acrylic,” Race says. “This price delta has been shrinking over the past few years. In many cases polycarbonate may be procured with less cost.”

This is something sign makers should certainly consider as they are choosing which materials to use for each job: price versus performance.

Strength—Durability has always been an attractive quality for sign users. The customer wants to know that he can rely on his investment and, thus, the sign shop that provided it to him. The advantage to polycarbonate is that it is very strong and dependable.

“Polycarbonate is significantly stronger than acrylic and impact modified acrylic,” Race says, “especially after being thermoformed.”

According to manufacturers, polycarbonates are far superior than acrylics in the strength category.

“Lighter than glass, Polycarbonate delivers more than 30 times the impact strength of acrylic, and 10 times that of impact-modified acrylic, so signs maintain their appearance over time, and can be used in areas of high vandalism,” says Jay Millhof, SABIC strategic account manager, image market—Polymershapes.

Against other substrates, plastics can also be looked at as a very trustworthy alternative, especially when considering their complete compilation that enhances longevity.

“Plastics can be engineered to be more durable than metal or wood; over time, they will not rust like metal or rot like wood.

 

Used with LEDs

Lighting is a big part of today’s signage. Users who want to make sure their displays are seen everywhere – in the dark, in the back of a store, among other displays, and more – are turning to LEDs for an illuminated advantage. Plastics can team with LEDs to make sure the best results are achieved.

“Because synthetics can be engineered to provide varying levels of opacity, they can work very well with LED and other lighting systems,” says Buckley. “Some plastics have higher heat tolerances than others, and can withstand the heat from other types of lighting systems without warping or posing a safety hazard.”

Polycarbonates, specifically, are great options for backlit and illuminated signage applications because of their ability to transmit high-clarity light. Sign makers should take note of the amount of light that is emitted through a sign face, especially in thin sign cabinets or closely configured applications.

For instance, “SABIC’s LEXAN sign white SGC510D sheet provides uniform light diffusion to eliminate LED pinholes and a view of light sources, and superior light transmission for exceptional optical brightness at lower energy costs,” Millhof says.

In the end, sign makers can consult with manufacturers to make sure they are using the best possible option for lighted signs.

“Many manufacturers offer grades specifically developed for the sign industry,” Race says, “these include LED compatible grades and digital print grades.”

 

Practicality for Sign Makers

For sign shops that are offering their services in plastic signage, it’s important to consider all of what the user wants in the sign. For example: Where is it being placed? What is the application?

“Polycarbonate signage is a durable and versatile option in a wide variety of applications,” Millhof says. “It’s an excellent choice for decorated outdoor signs, including cabinet signs and channel letters. LEXAN polycarbonate sheet comes in a variety of specialized sign grades, can be thermoformed with crisp detail, offers excellent aesthetics, and is tough enough to withstand high impact and abuse.”

Even between polycarbonates versus acrylics, there can be some major differences. Sign makers should give thought to which option should be used per project.

“There are many differences in the materials when it comes to fabrication,” Race says. “Both products can be cut easily with saws and routers. Polycarbonate can be die cut, guillotined or sheared, which is common in thinner gauges. Acrylic cannot be cut with these methods. Polycarbonate, unlike acrylic, can be cold formed and bent in a brake press. Both products can be thermoformed, but polycarbonate needs to be pre-dried to release excess moisture, as the forming temperature is much higher than acrylic.”

And, again, keep in mind that the environment will have an impact on the integrity of the sign.

“Acrylic sheet can be used both indoors and outdoors,” Race says. “Polycarbonate with a co-extruded UV cap layer, like Makrolon SL, is intended for outdoor use. General purpose polycarbonate should only be used in indoor applications.”

As a sign maker, there are always a number of factors to consider when trying to implement the best signage solution for the customer. If plastics are potentially part of the project, then look at the following:

  • What’s the budget? Plastic may be a more attractive option than other substrates, and acrylics are typically very affordable.
  • How long does the customer want the sign to last? Polycarbonates have a very strong composition.
  • Will the sign be used in outdoor or in lighted settings? Check how each element will perform against the customer’s checklist.