Durable Labels

Polyester Labels

Polyester Labels Withstand a Host of Environmental Effects

When it comes to demanding applications that require labels able to withstand extreme conditions and temperatures or interaction with caustic substances, durable polyester labels offer a proven solution.

Liberty Marking Systems offer a wide range of Polyester Labels in a variety of sizes featuring many advantages.

Polyester Label Advantages:

Our Polyester Label options include:

Polyester Labels – Frequently Asked Questions

Liberty Marking polyester labels are rugged and typically last 5 - 10 years. The actual service life of the polyester label depends on variables such as the application environment and exposure to elements such as temperature and chemicals.

We can produce and ship polyester labels in as fast as 1 or 2 days. The quantity of labels needed and printing requirements will ultimately determine the turn-around time. When you let us know more about your project, we’ll be able to give you a more accurate estimate on turn-around time.

Yes, we are able to produce metalized polyester labels.

Liberty Marking can produce polyester labels in any polyester materials that are available on the market including white or silver polyester, polypropylene (BOPP), clear films, label-lyte and more!

Our polyester labels can be formulated to stick to any flat or smooth surface.

Yes, our polyester labels are water repellent, however the type of ink used for the printing should also be considered for best results.

Liberty Marking is a UL approved label supplier. As such, we can work closely with you to assure your polyester labels are UL compliant.

Liberty Marking offers in-house and third party testing services.

Liberty PolyStrong

Liberty PolyStrong is a white biaxially-oriented polypropylene label stock with an aggressive, permanent adhesive, backed with a coated kraft liner. The adhesive is designed for a variety of surfaces including drum applications and provides excellent adhesion in all weather conditions, and is suitable for outdoor applications for up to two years. Our PolyStrong labels even work great on wood or rough surfaces. This face/adhesive combination conforms to BS5609: 1986 Section 2 and Section 3 – ‘Maritime and Laboratory Performance of Label Base Materials for drum labelling.’
This product is designed for use in a variety of printing applications where durability, strength, and superior printability are key.

Under the Hood Labels

Durable Under The Hood Labels to meet your requirements

The automotive industry requires durable labels to withstand harsh and oily conditions to ensure legibility at the time of assembly to follow the stringent requirements of the Automotive Assemblers. These labels are critical to ID parts with a barcode and/or human readable number for traceability. Liberty Marking Systems has decades of experience collaborating with companies that need durable polyester label materials with strong adhesives that can even be applied to oily parts. We provide the flexibility to preprint your labels, or we can supply you with blank labels to print your own variable information. We are committed to helping supply you with durable under the hood labels that will last throughout the life of the automobile.

Under the Hood Label Options Include:

Chemical Drum Labels

Chemical Drum Labels Meet OSHA, GHS and BS5609 Demands

The GHS (Globally Harmonized System) classification system has been adopted by OSHA (Occupational Health and Safety Association) as the labeling standard for the identification of potentially hazardous chemicals. GHS regulations mandate that chemical labels are required to include specific information and be printed according to specified guidelines. Liberty Marking Systems has extensive experience in the development of GHS labels as well as British Standard BS5609 labels, which is a specification for printed pressure-sensitive, adhesive-coated labels for ‘Maritime and Laboratory Performance of Label Base Materials for drum labelling.’

Chemical Drum Label options include:

GHS Drum Labels – Frequently Asked Questions

Yes. We have several materials that meet sections 2 and 3 of the BS5609 classification. Our relationships with raw material manufacturers provides us with several material options, as well as thermal transfer printers and ribbons, which are also factors in being complaint with the BS5609 requirements.


We stock several of these materials and can typically produce your labels within a few days of receiving your order. Send us the specifics regarding your chemical label needs and we can provide a more concrete turn-around time for your items.

Liberty is an authorized reseller of Tharo Systems labeling software, EasyLabel. We will help with the installation of the software, as well as programing the different label formats that you need for your chemical drum labels.

Depending upon how your products will be shipped, domestically or internationally, we can offer the right material to ensure compliance. Domestic shipments can utilize less expensive paper materials, while international shipments will need a more durable Polypropylene or polyester solution.

Product Identifier: Product Identifiers are meant to prevent accidental or unknown exposure with the ability to accurately identify the chemical and its hazard. Product identifiers are the ingredient names or number of the pure chemical substance or chemical mixture. Technical name(s) must correspond with IUPAC, CAS and technical names on the MSDS sheet. If the chemical mixture is regulated under the United Nations Recommendations on the Transport of Dangerous Goods, then the name must also correspond with the UN Proper Shipping Name.

Signal Words: Signal Words communicate relative hazard severity and alert to a potential hazard. The signal word “Warning” and the number “1” specify less-severe/non-lethal hazards while the signal word “Danger” and the number “2” specify severe or potentially lethal hazards.

Hazard Statement: These words or phrases are meant to describe the nature and degree of the hazard of the chemical. Hazard statements should be on the label for a chemical or substance possessing more than on e hazard. For example: “Heating may cause explosion.”

Caution Statement: The Precautionary Statement describes recommended measures to minimize or prevent adverse effects resulting from exposure. First aid information is also included.

Supplier Information: Each chemical containers, as well as secondary packaging (crates or master cases) are required to include supplier information. Supplier information includes: names, address, and telephone number of the manufacturer or supplier.

GHS Pictograms (Diamond-shaped symbols) Diamond-shaped red, black, and white pictograms communicate information about the hazardous risks associated with a chemical. Paired with the signal word (discussed below), the pictogram communicates severity of the risk and prevents accidental or unknown exposure. More then one pictogram may be used for the same label if/when applicable. Pictogram size and other label elements should be proportionate to the dimensions of the label.

Liberty is your one stop shop for a complete chemical label printing system. We provide all the necessary equipment, software and supplies for your company to be BS5609 complaint when printing your GHS Labels.

High Temperature Labels

High Temperature Labels Take the Heat and Keep Performing

When you need high temperature labels for specialty applications, Liberty Marking Systems offers a complete selection of products to meet your requirements. Our Polyimide Labels are ideal for use in extreme high temperatures and applications involving harsh industrial solvents. We offer high temperature labels that can withstand temperatures up to 1,000°F for a few seconds, temperatures greater than 700°F for a few minutes, and above 500°F for hours.

High Temperature Label Specifications include:

Our High Temperature Label options include:

High Temperature Labels – Frequently Asked Questions

Our High Temperature Labels are designed to be used in many ways for various products and various applications. Some materials are designed to endure intense exposures during production only, while other materials are needed to withstand periodic exposures to heat and or chemicals during a products life-time. Each application is unique and specific. Because of this we always recommend testing of any material. In general, the labels offered have been used by customers all over the world for common and unique applications with great success. Rest assured that working together we can guide you to the best material for your need.

  • Blank Stock Labels with Stock Die: 3-5 working days
  • Blank Stock Labels with Custom Die: 7-10 working days
  • Printed Stock Labels with Custom Die: 10-12 working days
  • Some uncommon custom materials can have a lead time of 15-20 days but that is very rare

Yes, RoHS specifically restricts or bans the use of lead, among other hazardous chemicals used in the manufacturing process.

Yes, our High Temperature Label Materials are Compliant with REACH initiatives set forth for the Electronics Manufacturing Industry.

We offer materials including labels and tags for various harsh environments including:

PCB Labels: Chemical Resistant Polyimide for Printed Circuit Board applications. Our product line exceeds harsh environment requirements for use in electronics, electrical, automotive and aerospace.

ESD Safe Labels for PCB: Antistatic Label Materials for PCB and Component Labeling Electronic Discharge damage affects production yield, product reliability and profitability in the electronics market.

Flame Retardant Labels: As electronic devices continue to get smaller and more complex while often requiring greater power, the risk of a fire event increases. Liberty offers a series of Labels that are made from Flame Retardant and Halogen Free Label Material that won’t contribute to fuel for propagating fire.

Hot Metals Processing: High Temperature Aluminum Labels and Polyimide Tags: This product line provides superior high temperature label and tag solutions designed to withstand extreme track and trace applications in the steel and aluminum industry.

High Temperature Tags: Liberty offers High Temperature Tags in both Aluminum and Polyimide. These tags withstand high temperatures encountered in many processes and also exhibit tear resistance make them an ideal choice for steel or any other hot material requiring a hang tag (up to 600C short term / 350C long term)

Laser Markable Labels: Black and White Polyimide materials are easily ablated by a wide variety of lasers to provide longer term durability and increased contrast and readability over traditional thermal transfer printed labels for high temperature and harsh environment applications.

Standard materials use an acrylic pressure sensitive adhesive.

Silicone adhesives are thermally more stable than are acrylic adhesives but because they are more expensive than acrylic they aren’t widely used. For any application that requires a label material to perform beyond the range of acrylic adhesives we offer two materials; XF-546 and XF-594.

Yes, all our Polyimide labels resist the most common chemicals found in fluxes and cleaners throughout the electronics industry. Our spec sheets list chemicals tested but we always recommend sampling and “Real World” testing before any purchase is made.

Effective Service Temperature depends not only on the external or applied temperature, the mass of the product that the label is adhered to and the heat source, but also the length of time that the label is exposed under those conditions.


Our Liberty Series 501 for example can withstand temperatures up to 1,000F(538C) for about 7 seconds. It performs well at temperatures greater than 700F(371C) for 10-15 minutes and above 500F(260C) for about 12-24 hours.


Similarly, our other high temperature Polyimide products exhibit their own time/temperature Effective Service profile. Although we can give you guidance based on our laboratory results, you must test each material thoroughly for your specific process times and temperatures.

Polyimide does not shrink, even at temperatures up to 500-600°F, unlike most other synthetic filmic materials. It is chemically resistant, and exhibits very high dimensional stability, even at high temperatures (up to 300 degrees C). It does not stretch, while being coated or converted. Because Polyimide films are dark amber in color, they must be coated with an opaque top-coating for any printing to be legible, and especially for the print contrast to reliably scan bar codes. These attributes make a polyimide pressure sensitive label ideal for identifying printed circuit boards and components in the electronics industry.

First you must define the process conditions so that you can quickly select the right materials. Do you have a thermal profile of your process? For each step of the process, how hot will it get? How long at that temperature? What is the maximum temperature the product will be exposed to? How long at that temperature? What chemicals will be used to clean the products after the manufacturing steps? Do you want to print and apply automatically? The answers to these questions will dictate the proper combination of ribbon and label material to give you durable, scannable labels throughout your process.

The industry standard "work-horse" is our 2 mil white Polyimide, known as XF-582. By understanding the process parameters, you may discover that your particular process conditions may not require these 2 mil polyimide labels. Newer lower cost materials including XF-519 and XF-529 are an excellent substitute. Need something with a more aggressive adhesive or a higher resistance to chemicals? The XF-557 would be the right choice. Whatever your application requires, Liberty’s broad product line should be able to provide you with a solution.

High Temperature Polyimide Labels require the use of a premium high temperature ribbon resulting in the need for an industrial printer with temperature and speed adjustments.

Most any high quality industrial printer with the correct ribbon combination will suffice, however if you are running very small labels we highly recommend CAB Squix Center Justified Series printers as they handle small label registration better than any printer that we’ve tested. In addition, unlike other popular printers on the market that can randomly lose numbers within a data sequence (often unknown by the user), CAB technology eliminates this occurrence.

Kapton® is Dupont's' trade name for it's brand of polyimide film. Although there are certain chemical differences between Dupont's "flavor" as compared to others, as in the famous "Coke vs. Pepsi" debate, the differences are inconsequential when used as a base for label materials.

The main point to remember is that Polyimide label material, whether it be Dupont's Kapton® label material or some other polyimide, is used for high temperature bar code labels because it survives the high temperatures required for circuit board manufacturing, without shrinking or melting. This provides a dimensionally stable base for the printing on the surface enabling the bar code symbology to remain within ANSI standards.

"Effective Service Temperature" depends not only on the external or applied temperature, the mass of the product that the label is to be adhered to, and the heat source, but also the length of time that the label is exposed under those conditions. For example, XF-557 can withstand temperatures up to 1,000°F (538°C ) for about 7 seconds. It performs well at temperatures greater than 700°F (371°C) for 10-15 minutes, and above 500°F(260°C ) for 12-24 hours. Similarly, the other THERMOGARD® products exhibit their own time/temperature Effective Service profile. Although we can give you guidance. based on our laboratory results, you must test each material thoroughly for your specific process times and temperatures.

"Effective Service Temperature" depends not only on the external or applied temperature, the mass of the product that the label is to be adhered to, and the heat source, but also the length of time that the label is exposed under those conditions. For example, XF-557 can withstand temperatures up to 1,000°F (538°C ) for about 7 seconds. It performs well at temperatures greater than 700°F (371°C) for 10-15 minutes, and above 500°F(260°C ) for 12-24 hours. Similarly, the other THERMOGARD® products exhibit their own time/temperature Effective Service profile. Although we can give you guidance. based on our laboratory results, you must test each material thoroughly for your specific process times and temperatures.

Flood coating is a printing process by which a coating of ink or varnish is printed across the entire label area. Oftentimes this is done to change the background color of the label. It is possible that the addition of a second color coat on a finished Liberty material may alter the performance of the base material, so be careful. 

For example, flood coating an ESD material may severely alter the surface resistivity of the material, so that it no longer complies with EOS/ESD standards on static dissipative materials. In another case, the finished flood coat may not have the same thermal transfer print receptivity, as the standard surface, which means that the printed image may not survive process chemicals and cleaners.

The strictest definition is that it is one that contains no lead, or other heavy metals such as Chromium, Cadmium, Mercury, organotin compounds and the like which are harmful to not only human beings, but also to the environment. However, in the context of today's "lead free manufacturing process" embraced by the electronics industry and European Union (known as ROHS), it has a much wider meaning. "Lead Free Labels" are those label materials which not only are "lead free" themselves, but which are also designed to be used in the new ROHS manufacturing processes, which will require higher soldering and processing temperatures.

All of Liberty’s labels MEET ROHS requirements and are LEAD FREE

All of our standard label materials typically use an acrylic pressure sensitive adhesive. Silicone adhesives are thermally more stable than are acrylic adhesives. Liberty offers two Polyimide products with silicone adhesive (XF 546 and XF 594, respectively) for those applications that require a label material to perform beyond the range of acrylic adhesives. Remember that silicone adhesives are also more expensive than acrylic adhesives.

ESD stands for Electrostatic Discharge. When a label is peeled from its release liner, it may generate a static charge up to 5,000 volts. To put it into perspective, on a dry winter day when you get "zapped" by a door handle after walking across a carpet, you feel about 15,000 volts. Electronic components are damaged oftentimes with a discharge as little as 200 volts. Liberty’s unique Triboguard technology is designed to dissipate the static charge as quickly as possible, i.e. as it is formed. This means that any charge generated, it dissipates quickly. The greatly reduced amount of static charge generated when these labels are removed from their release liners (<25 volts/square inch of label peeled), make them safe enough so they won't damage static sensitive components.


Liberty Offers our XF-781 (1 mil) and our XF-782 for your ESD labeling needs.

We all love the smell of a new car...there's nothing quite like it. One year later...have you noticed that" the new car smell" is diminished, but that there is a haze on the windows… even when you have never allowed ANYONE to smoke in your car?  Additives are put into the vinyl (and other plastic) seats in your car to soften them, protect them from spilled liquids, etc. However, over time, and in hot parking lots, these chemicals may evaporate, ever so slowly, and redeposit themselves onto other surfaces inside your car. The lovely "new car smell" is an example of OUTGASSING, and the foggy window is typical of the long-term effects, a haze deposited on surfaces. Many materials will emit gases under heat, such as the heat of the sun on the interior of your car.


These "volatile" materials are present in almost all polymeric/synthetic materials, such as coatings, films, and adhesives. As heat is applied, the volatile organic compounds (or VOC's) evaporate from (in the case at hand) the Polyimide or Kapton label. The gaseous molecules are free to be re-deposited on a cooler surface, such as a car window, mirror, or any other surface.


In the case of labels, the VOC's include small amounts of residual solvents from the coating process, plasticers, additives, and un-reacted monomer from the variety of polymerizations used to create the materials.

Out gassing of VOC's is exacerbated in outer space due to the major decrease in atmospheric pressure, i.e. high vacuum. Volatile materials boil at lower temperatures under reduced pressure. So, what might have been a high boiling VOC on Earth, may become very low boiling, i.e. easily out-gassed, in outer space. In addition to fogging up optics, windows, mirrors and the like, the out gassing may also cause adhesive failure of labels As the liquids "boil off" into gaseous form, they create pressure under the surface of the label. The pressure pushes against the label surface, since the gas wants to increase its volume. The result may be that the labels are "blown off" of the objects they are adhered to, thereby rendering them useless as identifiers.

A UL flammability rating is highly regarded as evidence for the suitability of a polymer or compound for a proposed application. A US company (RTP) has published a guide to the tests and procedures involved in obtaining UL listings. For example, UL94 V-0, V-1 and V-2, are probably the most widely cited ratings as evidence of the behavior of a plastic materials under burning conditions. Each of these tests require the examination of the material in the form of 5 x 12.5 mm. strips in three different thicknesses, respectively. A total of ten samples are tested in two sets at each thickness, one set after conditioning for 48 hours at 73°F(23°C); and 50 percent RH, and the other after similar conditioning for 7 days at 158°F(70°C). In the test, a specimen is mounted with its bottom end above a Bunsen burner tube, and a blue high flame is applied to the center of the lower edge for 10 seconds. If burning ceases within 30 seconds, the flame is reapplied for an additional 10 seconds. If the specimen drips particles, these are allowed to fall onto a layer of untreated surgical cotton placed 12 in.(30 cm.) below the specimen. The different categories depend upon 1. whether the plastic burns at all; 2) if so, whether it drips molten material as it burns?; and, 3) whether the dripping material starts the cotton burning, or not.


Liberty Offers our XF-600 series of labels, including 7 colored labels that meet UL94

Our materials meet MIL-STD 202G, Notice 12 method 215K & MIL-STD 883E, Notice 4 Method 2015.13. These tests are to verify that the markings or color coding will not become illegible or discolored on the parts when subjected to solvents and processes normally used to clean solder-flux, finger prints and other contaminates from printed wiring and terminal board assemblies etc.