Features

Synthetic Paper

By Steve Katz, Editor | January 20, 2017

Its properties make it an attractive substrate selection for a variety of applications.

In 2005, Label & Narrow Web’s associate editor at the time, Talar Sesetyan, wrote an article titled “Synthetic Paper: What is it?” This was nearly 12 years ago, and of course much has changed over that span of time – and I’m not referring to label substrates.

The back issues of L&NW are archived on our website, and they go back as far as 2004.  Using Google Analytics, we have the opportunity to see which articles get read the most. We can not only see what stories garner the most interest but also how long readers stay on a given page, and how they got there – whether it’s the words they typed into Google or a link they clicked on a social media site, for example.

We get monthly reports on what’s being read on the L&NW website, and sure enough, time and time again, “Synthetic Paper: What is it?” from 2005, makes our top ten list of most viewed articles. In fact, without even using the words “label” or “narrow web,” a Google search of the two words “synthetic paper” brings up Talar’s article on the very first results page, listed eighth out of nearly eight million landing spots. As we put our 2017 editorial calendar together, we decided that an update on the topic was long overdue. So, here it is.

By Definition
Per the Global Market Insights 2016 research report, the global synthetic paper market size is projected to grow to 209.7 kilotons by 2023, an estimated gain of 6.1%. “Label market growth is estimated to be the highest, with gains at 6.3% up to 2023 and is predicted to exceed 80 kilotons,” says Alan Harsey, print technologist at Arjobex America.

We know it’s an area of growth, but what is it? The definition of synthetic paper is somewhat fluid, and the answer to the question is largely dependent on what supplier you ask, and what their company offers the label industry. For this article, we’ve reached out to a few experts, and their definitions vary.

Jason Depner, PPG global segment manager, Teslin Substrate Products, explains that synthetic paper is any printable material that isn’t made from wood pulp or natural fibers. He says, “While synthetic papers are typically polymer-based, not all are equal in composition. Different polymers or polymer blends offer different benefits, so users need to define the right composition that fits ideally with their application.”

According to Jack Smith, senior vice president of Hop Industries Corp., “Synthetic paper is a white opaque plastic that is made from either polypropylene (PP) and polyethylene (PE) plastic that has been modified with a calcium carbonate coating (CaO3) or clay filler (CaO3) to enhance its dyne level for better ink adhesion and brightness for printing durable tags and labels.”

Cecily Randall, international sales at Channeled Resources Group, gives it to us in layman’s terms. She says, “Synthetic paper is a cross between paper and film. Synthetics are resin-based, so they share some appealing characteristics of film such as tear resistance, water resistance and grease resistance. While synthetics don’t feel like paper to the touch, they emulate paper’s bright white, printable surface.”

Advantages and attributes
When choosing a substrate for a labeling application, converters must steer their customers toward what best suits the end use. Every roll of labels has a different requirement, so substrate choice will take into account many factors. Some examples: White wine labels need to withstand an ice bucket bath, shampoo bottle labels need to hold up for weeks or months in moist, humid bathroom environments, lawn mower labels need to withstand the outdoors and sunlight, and so on.

So when does the application point toward synthetic paper? And what advantages does it have over traditional paper or film?

You might say synthetic paper provides then best of both worlds of paper and film. Harsey says Polyart, Arjobex’s synthetic paper, combines the advantages of paper with the durability of plastic. “Polyart looks, feels, prints and converts like a premium matte-coated paper but stands up to water, weather, grease, chemicals and resists tearing,” he says. “It has the printability of paper with the durability of plastic.”

“A real advantage they have over paper is resistance to yellowing and a much longer shelf life,” says Randall. “Synthetics are used in a variety of applications requiring strength and resistance to the elements. For example, drum labels where resistance to chemicals may be necessary, or medical applications, such as labels or patient wrist bands, where moisture and tear resistance is critical. Synthetics are also extremely popular for outdoor tag applications for lumber tags, nursery or other horticultural products.”

Depner points out that synthetic papers were designed to be durable like plastic, but look, feel and print like paper. “The durability benefits of synthetic paper-based labels typically yield higher performance and extend lifetime. Leveraging the right synthetic paper can unlock properties that enable more complex labeling applications,” he says.

Echoing Randall’s thoughts, Hop-Syn synthetic paper from Hop Industries is popular for printing horticultural tags for trees and plants, as well as tags used for labeling different grades of lumber, explains Smith. “We also see demand for warrantee tags on outdoor equipment, expanded content labels for food and pharmaceutical products, injection molded labels, instruction tags, and bottle labels that need to be waterproof to enhance the brand image,” he says. “In addition, synthetic papers are a great fit for food labels that need to be FDA-approved for direct food contact. This is because they are directly applied to poultry, beef, sausage and cheese products that would promote a fresh image that would hold up in the refrigerated section of the supermarket.”

Smith maintains that in comparison to straight plastics, such as PVC vinyl and polystyrene, synthetic paper offers better ink adhesion along with a brighter white finish, thus allowing converters to produce sharper graphics with a higher color resolution that would enhance the printed image.

IML applications
When it comes to in-mold labeling (IML), Bill Hewitt, marketing manager for Yupo, says that synthetic papers are a sustainable solution. “They are usually a lower per unit label cost than post-mold alternatives,” he says. “Plus, they provide higher line speeds and efficiency while eliminating need for post-mold stations. And they lessen maintenance and reduce manpower needed, compared to paper.”

Paper IML is fragile and complex compared to synthetic IML, Hewitt explains. “Paper IML must be stored in a controlled environment to avoid curling related to humidity, which can also cause interactions between the coating and adhesive. When using paper, an adhesive must be applied. This is much harder to control compared to synthetic IML, which comes with a pre-applied adhesive coating that is ready to adhere to the bottle.”

There are additional price and eco-friendly advantages. Hewitt says, “Paper IML tends to actually be higher in cost due to the synthetic advantages of faster cycle times, less waste and the ability to be reground. A huge disadvantage for paper IML is having to remove the paper IML label prior to recycling the bottle. With synthetic IML, the entire bottle and label can be recycled together since the label becomes one with  the bottle at time of application. All of these factors play into the fact that synthetics are usually preferred over paper by recycling companies.”

PPG’s Teslin
PPG’s Teslin substrate accommodates almost every conventional or digital printing process, making it easy to process high-quality color labels using on-demand print technologies. “The material’s thermal stability makes it compatible with more print technologies than similar synthetic papers and printable plastics, without needing corona treatment or pre-print coating,” Depner explains. “For end users, this feature reduces potential failure points, complexity and overall product cost.”
PPG recently introduced a line of labelstocks based on its Teslin substrate. “Compared to synthetic label materials, Teslin labelstock stands alone in its ability to protect printed data while providing superior flexibility in print technology compatibility, as well as high-quality text, photo and color reproduction,”Depner says.

The key to Teslin’s durability is its microporous polyolefin-silica composition that absorbs and locks inks and toners into its structure as opposed to other synthetics where inks and toners have to cure on top of the plastic film. “Not only does this characteristic protect labels against exposure to moisture and chemicals, it also renders printed data practically impervious to the many scratches, scrapes and scuffs it will encounter during packaging, handling, shipping and storage,” he says.

When it comes to GHS labeling in the chemical industry, certain PS labels are vulnerable to static build-up.  Another advantage in Teslin is in how it reduces the risk of fire and other static hazards as its micropores absorb and dissipate static, reducing the threat of electrical discharge.

Security applications are another area where Teslin is a great fit, Depner adds. It is inherently tamper-evident, preventing counterfeiters from removing or altering security-enhanced labels by quickly and easily revealing any attempt to do so. “Additionally,” he says, “labels made from Teslin can provide extra functionality because the substrate can be embedded with security markers that verify the authenticity of a product throughout the supply chain.”

Polyart from Arjobex
Polyart synthetic papers from Arjobex are resistant to tearing and water, making it an an ideal substrate for outdoor applications, Harsey says, adding, “It’s also resistant to oily substances and most chemical products such as ammonia, caustic soda, isopropyl alcohol and more.

Due to its special manufacturing process, Polyart has no grain direction, which means it conforms easily to bottle shapes. “And it can withstand extreme heat and cold, remaining dimensionally stable up to +60° C  (+140° F) and down to -60° C (-76° F). Also, with its excellent UV resistance and weathering characteristics, Polyart will not shrink or become brittle, and its balanced physical properties make it conform well to irregular surfaces or very tight radii,” says Harsey.

Polyart adapts quickly to most printing processes, such as flexography, lithography, gravure, rotary letterpress, screen, as well as digital. Polyart’s clay coating is responsible for its ability to readily accept color. “And show it off beautifully,” Harsey adds. “Polyart ensures rich, vivid images with excellent ink holdout without requiring special preparation. No matter what converting method you have in mind, Polyart is ready to go to work for you. It can easily be scored, folded, perforated, varnished, foil stamped, stitched and more, using standard converting equipment.”

Arjobex’s Polyart has sustainability benefits as well. “Polyart papers are 100% tree free, 100% recyclable in category 2 HDPE, and therefore very environmentally friendly.  The Polyart manufacturing process uses five times less water than traditional paper production. And Polyart labels can be recycled together with the containers they’re adhered to,” Harsey says.

Arjobex offers a full range of Polyart materials for the pressure sensitive narrow web market. “From the industry standard 3 mil grades in either coated one side or both, to our thickest grade of 13.5 mil for the heavy duty tag applications,  Arjobex has the thickness to get the job done. We have tamper evident material for the most demanding of the security print requirements. Arjobex recently introduced digital compatible products for Indigo and inkjet technology. We have developed a non-coated pressure sensitive label grade to address price-sensitive applications. Whatever the labeling application, Arjobex makes a Polyart grade to meet or exceed the requirements,” Harsey concludes.

Paper Tyger from Channeled Resources
With durable substrates becoming increasingly more prominent in the label industry, it prompted Channeled Resources Group to offer Paper Tyger, a popular durable paper that was developed as a cost saving alternative to synthetic papers. “The beauty of Paper Tyger is that it prints and converts just like paper without the need for additives that can cause wear and tear on dies,” Randall says. “And it doesn’t require special inks or longer setup or drying time, all of which add cost to job runs as can be the case with synthetics.”

According to Randall, Paper Tyger’s consistent, smooth printing surface results in exceptional graphics, even on a desktop printer. “This is a distinct advantage Paper Tyger has over synthetic paper, which will melt in a laser printer,” she says, adding that Paper Tyger is a good fit for applications that require additional substrate strength and resistance. “A synthetic paper is the best choice for long-term outdoor applications, but a durable paper is well-suited for a short-term outdoor application,” Randall adds. The substrate’s outer paper layer has wet strength while the inner film layer provides a moisture barrier, as well as grease resistance. “This makes it a good choice when the finished product will be handled quite a lot,” she says.

Hop Industries’ Hop-Syn
According to Jack Smith, his company’s Hop-Syn synthetic paper has advantages relating to improvements in printing process efficiencies. He explains: “Hop-Syn is manufactured by the calendering process, which can produce a more uniform gauge control of +/- 5%. This allows flexographic and offset printers to print Hop-Syn synthetic paper at faster speeds for higher production and a more consistent print image. “The calendaring process also allows Hop-Syn to be made in a wide range of thicknesses from .003 up to .035 gauge, and maximum roll widths of up to 72".”

Hop-Syn synthetic papers are offered in a wide variety of paper grades, which are formulated from polypropylene (PP) resin with CaCO3 (calcium carbonate) and Tio2 (titanium dioxide) added to enhance its dyne level, brightness and opacity. “Although each grade of Hop-Syn may look similar in matte finish, the properties of each Hop-Syn grade are custom made to meet the opacity, brightness, tensile strength and elongation properties that the application requires,” Smith says. “This makes Hop-Syn more adaptable to different applications, which is why it is referred to as ‘The Application Synthetic Paper.’ Also, Hop-Syn is produced under ISO 9000 standards, and meet the environmental standards of CONEG and ROHS for North America.”

All Hop-Syn synthetic paper grades are 100% recyclable, waterproof, tear resistant, and temperature resistant from -60°F to 220°F.  Hop-Syn papers are ideal for multiple printing processes, including offset, lithography, UV offset, flexo, screen, UV inkjet and thermal transfer printing. “With in-house slitting and sheeting capabilities, combined with over 1,600,000 pounds of inventory, we have the ability to ship custom sheets and master roll inventory within 24 hours from the date of order,” Smith says. “For testing purposes, we offer free samples to evaluate the print quality and durability of any specific Hop-Syn grade for comparison to any other substrate.”

Yupo
Yupo offers all variations of IML substrates for HDPE, PE and PP bottles for injection and blow molding applications, as well as print methods from conventional, UV offset, UV flexo to gravure. Many types of Yupo synthetic papers are available with both textured and smooth finishes, as well as opaque and clear grades. Yupo is scratch proof, tear proof, waterproof and resists flagging.

The company’s latest product launch is Yupo Sculpt IML – a patented process that enables users to adhere a Yupo IML label to an embossed bottle. “The demand for a tactile label is huge industry wide,” says Hewitt. “This patented technology also provides extra anti-counterfeit benefits and eye-catching shelf appeal for the consumer. This we feel will revolutionize the label industry.”