A Guide to Heat Shrink Film

Shrink Film - a material made up of polymer plastic film. When heat is applied, it shrinks tightly over whatever it is covering. There are a variety of uses for Shrink wrap and shrink film. Some typical shrink wrap applications are for wrapping food, gift baskets, boxes, toys, books, soaps, etc. Below is a breakdown of the two most commonly used types of shrink.

PVC Shrink Film - A type of shrink wrap used for various applications. The PVC stands for Polyvinyl chloride. Polyvinyl chloride is the third most-produced plastic in the world. PVC shrink wrap was the most commonly used shrink film until replaced several years ago by polyolefin (POF) shrink wrap.

Common Uses of PVC Shrink Film - PVC shrink wrap uses include packaging boxes, CD and DVD packaging, software, small canisters, and other non-edible items.

Drawbacks of PVC Shrink Film - Sealing Strength, storage issues, and sealing by-products are common drawbacks of PVC Shrink Wrap. The plasticizer in PVC Shrink wrap hardens in cold conditions and softens under hot conditions, therefore compromising the strength of the seal and the plastic. PVC shrink wrap also releases small quantities of hydrogen chloride into the air and carbon deposits onto the sealer. Proper ventilation is required when sealing PVC shrink wrap.

Polyolefin Shrink Film - A type of shrink wrap that has become the preferred choice for packaging products, both edible and non-edible. Polyolefin Shrink wrap is preferred for a variety of reasons, including fewer odors when sealed, stronger seal, and more flexible storage. Polyolefin shrink films do not have any chlorine; therefore, they do not produce hydrogen chloride gas. Polyolefin shrink wrap does not have any plasticizers, so the temperature is not an issue. Polyolefin can be stored in a wide range of temperatures and does not harden and soften in different environments like PVC shrink film.

Common Uses of Polyolefin Shrink Film - Polyolefin shrink film is used for almost every kind of application. Applications include toys, sporting goods, printed wrap, foods, stationery, and cards, just to name a few.

Drawbacks of Polyolefin Shrink Film - Cost and machine compatibility are the two significant drawbacks of Polyolefin shrink film. Polyolefin is commonly more expensive than PVC shrink wrap. Many packagers prefer PVC because of this reason. There are types of polyolefin shrink wrap that are more compatible with machines, but Polyolefin machine compatibility has been an issue of packagers.

Cross-Linked Polyolefin Shrink Film - Irradiation is applied to standard polyolefin shrink film to make the film stronger, and capable of better seal strength. Cross-linked shrink film is sterile, and FDA approved for direct food contact. It offers excellent clarity to display packaged products. To view in detail about making and the history of cross-linked shrink film view, our blog post titled What is cross-linked shrink film.

Cross-linked shrink film also leaves less residue on sealers, promoting longer sealing blade or wire life. Cross-linked shrink film is made for use with high-speed machines and high output operations.

Common Uses of Cross-Linked Polyolefin Shrink Film - Cross-linked shrink film is used with the same products as standard polyolefin shrink film. The cross-linked film is often used in high output operations. It can also be used for heavier products; a conventional polyolefin shrink film can not correctly package.

Drawbacks of Cross-Linked Polyolefin Shrink Film - Cross-linked shrink film requires higher seal and shrink temps than a standard polyolefin shrink film. Higher temps can damage and deform products sensitive to heat. Higher seal and shrink temps. also, require higher energy costs.

Frequently Ask Shrink Wrap Questions

What is Shrink Wrap Used For?

Shrink wrap is a general term that can refer to many materials. Stretch film for wrapping pallet loads of products is often called shrink wrap. Heat shrink wrap is a different material that shrinks when heat is applied, often used to protect commercial, retail, and personal products. Both can be essential in preventing product damage or loss.

Can You DIY Shrink Wrap?

Yes, heat shrink wrap can be done by yourself with everyday household items, but the finished look is not as professional. PVC shrink wrap bags and a hair dryer will shrink around a product. Tape before heat is applied can help mend the shrink wrap together. The finished look will not be as clean as a sealer, but the wrap should stay over the product. We recommend buying a sealer, heat gun, and shrink bags for wrapping more than a small handful of products.

What is the Difference Between Plastic Wrap and Shrink Wrap?

Plastic wrap and shrink wrap are ambiguous terms that reference many different materials. Plastic wrap can be kitchen cling wrap, stretch film, cellophane, and other materials. Shrink wrap can be several of those materials as well. A heat shrink wrap is different from all materials because of the additives used during the extrusion process. Those additives allow the chemical compound of the material to contract when heat is applied without melting through the plastic.

Is Shrink Wrap the Same as Cling Film?

Although both can be made from comparable compounds, shrink wrap has additives specifically for shrinking when heat is applied. PVC used to be preferred in both cling films and shrink films. In recent years polyolefin has become a preferred material in shrink wrapping. Don’t apply heat to a cling film; it will melt.

How Do I Measure For Shrink Film?

Measuring shrink film is relatively simple but is determined by the type of shrink product you intend on using. See below for measurement formulas for every kind of film. Remember, if the exact size needed is not available, go to the next size up. All of our shrink films have a shrink rate of at least 30%.

Centerfold Shrink Film Measurement Formula

Width + Depth x 2 x 1.1÷2 = Centerfold Film Width Needed

Shrink Bag Measurement Formula

The same formula as above to determine the bag width, for length, add 1-2 inches to allow room for making a seal.

Shrink Tubing Measurement Formula

For squared objects, use the same formula as above, but most people use tubing for cylindrical purposes. If measuring for a circular object, use the equation below.

Circumference x 2 x 1.1÷2 = Tubing Width Needed

When Do I use Shrink Film, and when do I use Stretch wrap?

Shrink wrap is commonly used to protect and package a single product, like toys or a CD. It also is used to help bundle multiple products together. It is used to bundle soda, water bottles, and various other packaged products together. Usually, stretch wrap is used to hold boxes and products together on a pallet for transportation. It can also be used to hold other objects together for transport or storage. Stretch wrap can come in a variety of specialty films. Some examples are UV stretch wrap, vented pallet wrap, anti-static stretch film, colored stretch film, pre-stretched stretch film, etc. Are shrink wrap and stretch films recyclable? Both shrink wrap and stretch film are recyclable. Check with your local recycling center, and be sure they accept soft plastics.

Polyethylene Shrink Film- Polyethylene shrink film is used for packaging heavier products. Polyethylene shrink film (bundling film) is most often extruded onto single wound or flat rolls. The rolls are used on shrink bundling machines that have a sealing bar and shrink tunnel.

Drawbacks of Polyethylene Shrink Film- Polyethylene shrink film requires a shrink bundling machine to run products efficiently. Shrink bundling machines with a shrink tunnel can be expensive and cost thousands. Polyethylene shrink film also requires more prolonged heat exposure to shrink fully. Products sensitive to heat can melt or become damaged while the shrink film is obtaining a full shrink. Polyethylene shrink film has a low shrink rate of 15% or less. Product measurements are essential to ensure the right size of shrink roll is purchased.

Do I need a particular shrink wrap machine?

Different applications require machinery. When using shrink wrap, a heating instrument will be needed to shrink the film. There are a variety of devices to use, depending on what you are trying to accomplish. Typical tools are heat guns, L-Bar sealers, I-Bar Sealers, and shrink tunnels. View: A complete guide to shrink wrap machine cost.

Will a shrink wrap machine cut & seal the shrink wrap all at once?

Yes, most shrink wrap sealers cut and seal the shrink wrap film in one motion. Once sealed and cut, the scraps can be peeled away, and heat can be applied to the shrink wrap. The heat will reduce the size of the shrink wrap film and help to conform it to the product.

Can a hairdryer replace a shrink wrap heat gun?

Shrink Wrap Heat Gun No, if you are after a professional look, a heat gun is recommended. The wrap needs to reach 300 degrees Fahrenheit to shrink the film properly. Shrink wrap heat guns are very affordable. Click on the link to view our shrink wrap heat guns.

What gauge of shrink wrap do I need?

We recommend a 75 gauge shrink wrap for products less than 12 pounds. A 100 gauge shrink wrap is recommended for products up to 30 pounds in weight. To view our gauge conversion chart, click here.

What are shrink wrap bags?

Shrink bags are pre-measured bags commonly made from PVC shrink film and come in a variety of sizes. They offer the ability to place a product or products within the bag for a quick and secure seal. Shrink bags are used for packaging a variety of products including CD's, DVD's, gift baskets, assorted products, etc. If you are packaging products that will come into direct contact with food, polyolefin bags are required.

How do I measure for shrink wrap tubing?

Start by measuring the circumference of the object that will be shrink wrapped. Once the circumference is identified, add 10% to the circumference. Divide the final number by two, and that number will be the width of shrink wrap tubing you will need. If the width of shrink wrap tubing required is not available, it is fine to go with a larger size. PVC shrink wrap tubing can shrink up to 40% — view: How to measure for shrink tubing.

How do I measure for shrink wrap bags?

Measure the product being shrink wrapped around its widest point. Add 10% to that circumference and divide the number by two. This number will give you the width of the shrink wrap bag you need. Next, measure the product to be shrink wrapped all the way around from top to bottom. Once that number is determined, add 10% and then divide by two. This number will tell you the length of the shrink wrap bag needed — view: How to measure for shrink bags with illustrations.

Industries That Commonly Use Shrink Wrap

Games & Sporting Goods- Manufacturers, resellers, wholesalers, and retailers commonly use shrink wrap for wrapping a variety of goods and products. PVC shrink wrap is frequently used for these items. It helps to detour and detect tampering and is an affordable form of packaging.

Printing & Paper Products- Many companies in this industry use shrink wrap to protect their products and goods, detouring and to detect tampering. Food- One of the largest industries that commonly use shrink wrap. Wrapping in shrink film helps to remove oxygen contact from the food and can reduce waste. POF (Polyolefin) shrink wrap is the typical shrink film used for food packaging. Be sure the POF shrink wrap you choose is FDA approved for food contact.