Tips and Advice on Heat Shrink Labels

HEAT SHRINK SLEEVE MATERIALS

There are different types of heat shrink sleeve materials on the market. Read on to learn about PVC, PET, and OPS products.

PVC shrink labels — This material is easiest to control in the shrink process and is generally the most cost effective. PVC offers good scuff resistance.

PET shrink labels — This material offers the best scuff resistance and the highest percentage of shrink. It is easily recycled.

OPS shrink labels — This material is more cost effective than PET. It offers the lowest vertical shrink and therefore has the most consistent finish. It is often used for "squeezy" containers.

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GRAVURE FOR HEAT SHRINK SLEEVE PRINT PROCESSING

Gravure printing is a proven technology and high-quality printing method using solvent based inks. The graphics for each color is etched onto individual metal cylinders. The benefits of gravure printing include:

• • High quality photographic reproduction
• • Reduced size text for extra information and special offers
• • High quality origination gives consistency of reproduction over an extensive timeframe.

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BENEFITS OF FLEXOGRAPHIC PRINT TECHNOLOGY

Flexographic heat shrink sleeve processing has many benefits, such as its low cost and high-quality production. But what is it exactly?

There is Central Impression (CI) Flexographic print technology and UV Flexographic technology.

CI Flexo is a solvent based process, based on a raised areas such as dots, lines, or blocks on a photopolymer plate. Ink is transferred onto a plate and then the film and each color unit prints in sequence.

The greatest benefit of UV Flexo is the immediate achievement of finished print, ready for subsequent processing. This is obtained through the UV light crosslinking the wet ink to give a dry product. Therefore, the time for the print either to oxidize or to lose the slow evaporating solvents has been eliminated.

UV Flexo utilizes the same printing plates as CI Flexo but is a solvent free ink process. Each color is printed onto the film at a separate station and is cured with UV lamps. This gives greater depth of color and reproduction than CI Flexo.

The benefits of both include:

• • Low-cost, high-quality reproduction.
• • Rapid response due to shorter origination process.
• • Suited to promotional and labeling requirements.
• • Multi variant possibility.

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DIGITAL PRINTING FOR HEATSHRINK

Heat shrink labels can additionally be printed using digital printing. Inkjet and laser printing technologies are among them. These printing technologies eliminate printing plates, allow shorter print runs, and feature customized printing. It is ideal for personalized labels and small batches. Droplets of ink form the images and text on heat shrink with inkjet printing. Laser printing provides a high-resolution option for images and text, with it specified on the heatshrink which type is “laser printable.”

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METHODS FOR APPLYING HEAT SHRINK LABELS

There are two methods of applying heat-shrink labels: full-body shrink sleeves and roll-fed systems.

Both involve placement of a plastic film — averaging 50 microns in thickness — around a bottle, followed with the application of heat. The heat shrinks the film to the contours of the bottle.

Automated state-of-the-art systems and processes are continually in development for shrink sleeve applications.

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THERMAL TRANSFER PRINTING

A thermal transfer printer features a thermal print head that imprints ink from a ribbon onto heat shrink. Barcodes and durable labels are among the items generated from thermal transfer printing.

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HOW HEAT SHRINK TUBING WORKS

Heat shrink tubing is the most convenient way to label and organize wires, cables, cords, and conduit. Heat shrink tubing is an alternative to some other approaches to insulation such as taping or molding in place. The tubing can come in a wide range of sizes, colors, and materials. When heated, it shrinks to conform to the size and shape of the underlying material, making installation fast and easy.

Here's how it works:

• • Print out the heat shrink label
• • Slide it over the wire or cable to be labeled.
• • Once the label is in place apply heat to the label.
• • It shrinks to fit securely over the item.

The result is a flexible and durable marker that keeps its look for years. Experts say to avoid overheating heat shrink tubing or it can become brittle or char.

Options for shielded heat shrink tubing include: Shrinkflex® Shielded 2 to 1 Heat Shrink Tubing. This combines polyolefin heat shrink tubing with conductive cloth weave to provide high-frequency EMI shielding properties for sensitive cables and wiring. The tubing shrinks with a heat gun, oven, or any other conventional heat source. Coaxial cable butt joints and cable to shielded connector housing joints can be made fast and easy and without the use of solder.

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WHAT HEAT SHRINK GUNS CAN DO

Heat shrink guns are used for shrinking heat shrink tubing, and shrink wrap. But it can be used for other tasks like removing paint. A heat gun also loosens adhesives and tiles. It helps to dry objects and defrost a freezer. Heat one up to stretch and bend vinyl, plastic, and PVC. It’s for activating adhesives, and stripping or removing paint or varnish. Certain steps in automotive repairs can additionally incorporate a heat gun. Use one to loosen rusted nuts, bolts, and fittings. Guns range in the degree of heat they emit. The intensity of the heat can range from around 250° F to upwards of around 2,500° F.

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CREATE HEAT SHRINK TUBE LABELS WITH THIS PRINTER

Panduit® PanTher™ LS8/LS8eq Label Maker can be an easy and cost-effective way to mark wires, cables, tubes, and conduit with heat shrink tubes. It is a handheld printer that can create high-quality labels, which can be individually cut or torn apart. Panduit® Heat Shrink Label Cassettes are sold separately.

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HEAT SHRINK LABELS ON THE RISE

Heat shrink plastic labels for packaged foods, beverages and other consumer products continue to rise as marketers seek to differentiate their products on crowded store display areas and shelves. They are already identifiable with buyers of coffee creamer, flavored milk, and drinkable yogurt. These labels have additionally found their way onto the packaging of juice, bottled water, pet food, pharmaceuticals, cosmetics, lawn care items, and automotive products.

Several advantages of heat shrink labels are:

• • Heat-shrink labels can provide eye-catching, high-quality, 360-degree wraparound graphics on a blow-molded plastic bottle or container.
• • They cling tightly to just about any bottle shape.
• • When extended to cover necks, caps and lids, the labels can add tamper-evident features to a container.

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DIMENSIONS NEEDED FOR ORDERING HEAT SHRINK TUBING

When you are ordering heat shrink tubing, you need to know certain dimensions.

You will need to know:

• • The expanded dimension
• • The recovered dimension

The expanded dimension is what the tubing measures when it is in its expanded state. The recovered dimension is what the tubing measures when it is heated and recovered on the rod. It is helpful to know what the outside diameter is of the object you are putting the heat shrink over. You should learn these dimensions. It is also important to know whether you want the heat shrink supplied in coils or straight lengths.

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TEFLON HEAT SHRINK ADDS STRENGTH, DURABILITY

For extra strength to your heat shrink tubing, order it in PTFE, which is a fluoropolymer resin.

PTFE heat shrink tubing is one of the most difficult of the fluoropolymer materials to shrink due to its extremely high shrinking temperature. This heat shrink type is available in 2:1 and 4:1 shrink ratios. It is widely used in military applications because of its high continuous use temperature and outstanding chemical resistance.

You can use a heat gun or welding torch to shrink PTFE but these methods have a tendency to cause the material to overheat in small areas. It may under-heat in other sections, causing uneven shrinking and potential burning of the material. The most reliable method for shrinking PTFE is the use of a controlled temperature oven. This is, however, impractical with large harnesses or temperature sensitive components.

Heat shrinkable Teflon® tubing or Teflon® heat shrink are common names for PTFE heat shrink. Teflon® is a registered trademark of DuPont™. PTFE has properties such as lubricity, chemical resistance, high temperature resistance, and more. The unique properties of PTFE have made it the polymer of first choice for many advanced applications. With the lowest friction of any polymer and a broad working temperature range, PTFE has been designed into products from advanced medical devices to high temperature industrial equipment. PTFE has become a choice plastic for the chemical and analytical sciences industries.

For a product that contains the benefits of all both PTFE and FEP (Fluorinated Ethylene Propylene). consider using PTFE/FEP Dual Wall Shrink Tubing, for a product with benefits of both PTFE and FEP. FEP has some distinct differences from PTFE. It has a lower continuous service temperature and is more transparent than PTFE. It also has better gas and vapor permeability properties, as well as excellent UV transmission ratings. The PTFE/FEP heat shrink features a “dual wall” construction. It is constructed with an outer layer of heat shrinkable PTFE and an inner layer of FEP. It is easy to apply, and is designed to provide a tight, moisture-proof bond over wires, cable, connectors, splices, terminals, and more. During application, the PTFE shrinks tightly over inserted parts, while the inner layer of FEP melts and flows to encapsulate parts, providing a tight moisture-proof seal.