The complete guide to shrink films

All you need to know about shrink film for packaging

What is shrink film? 

Shrink film, also shrink wrap, is a material made up of polymer plastic film, which is a reasonable cling wrap that is utilized to bundle a thousand of products such like fruit, cookie, bread, ect... over your imagine. Shrink wrap shrivels around the products being bundled when it is presented to warm and it shrinks tightly over whatever it is covering. 

How can we use shrink film?

Shrink film should either be possible with a heat gun or through professional shrink wrapping machine.

Shrink wrapping with a heat gun is frequently done by people who have an extremely modest number of items to wrap every week.

For company, a shrink wrap machine is necessary to effectively and rapidly wrap, no matter how many products there are, it can shorten the time within the expected range.

There is some tips you need to know about shrink wrap machine, both semi automatic shrink wrap machine and automatic shrink wrap machine, and other types of wrap machine.

The three main wraps materials are polyvinyl chloride (PVC), polyethylene (PE), and polyolefin (POF). Each one has their own different capabilities and characteristics that make them suitable for specific applications.

PVC shrink film

Polyvinyl chloride is a combination of carbon, hydrogen, and chlorine. In view of its lightweight characteristics, cheap price and versatility, PVC used to be the most commonly used shrink packaging material in the world. May you have noticed, the time of PVC are finished. For many reasons, the scope of PVC shrink packaging has fallen behind PE and POF. Specifically, it is due to the health hazards in manufacturing, incineration and sustainability.

PE shrink film

Polyethylene is a type of polyolefin, used in many forms of flexible protective packaging, including shrink wrap and stretch wrap, and works quite differently for each. The most common forms that PE can make would be Low-Density Polyethylene (LDPE), Linear Low-Density Polyethylene (LLDPE), & High-Density Polyethylene (HDPE), but for shrink packaging industry, LDPE would be the most common form.

POF shrink film

The main types of POF are polyethylene and polypropylene. POF shrink film is made of 100% recyclable materials, and there are several other good qualities which makes it safer than PVC. In addition, it is more durable which makes products not being affected by temperature changes. FDA approved it for food contact. 

Pros and cons

1、THE TIME OF PVC HAS PASSED.

When PVC is heated, toxic hydrochloric acid gas is released. Therefore, PVC poses a threat to factory workers in the production process and public health in the incineration or decomposition process. During use, proper ventilation is required when sealing PVC shrink packaging. In addition, PVC will leave carbon deposits on the sealing machine, which will increase the cost of regular maintenance. Due to the physical properties of PVC shrink film, it will become brittle under cold conditions and wrinkle under high temperature conditions, thereby damaging the strength of the seal and the plastic.

2、POWERFUL AND STRONG PE!

Compared with the other forms of shrink packaging, using LDPE would be added strength and durability for heavier, larger items. Meanwhile, it can have excellent graphics and image added and maintain the strength required. 

In particular, the maximum thickness of PE far exceeds that of POF and PVC. For example, in marine industrial applications, the thickness of the shrink wrap required by the shrink-wrapped ship for storage needs 1200 gauge! The thickness of POF and PVC is usually limited to about 100.

The disadvantages of PE shrinkage are lower shrinkage (usually about 20%) and a significant decrease in transparency.

3、POF IS A GOOD CHOICE.

POF shrink film has excellent clarity and glossy appearance, which makes it ideal for consumer products where appearance is critical. The ability to shrink completely and quickly, bundle multiple projects together, that make it the most widely used in the world now! POF relies on the versatility of multiple machines and packaging forms, and the low cost, making it the good choice for manufacturers of different sizes for protective packaging.

In some cases, the POF film needs to be perforated before it is applied. These holes allow air to escape during the shrinking process, thereby producing a smooth packaging with a uniform shrinking surface and no air pockets. Therefore, many suppliers provide pre-perforated shrink films.

How much does using shrink film cost?

The first step before we consider about the money is asking yourself some basic questions.

1.When you think about cost, what is the first thing that you think about most?

Price?

Cost of ownership?

Adaptability to your packaging machine?

Cost of storage and maintenance?

……

Next, we will involve some mathematical knowledge.

2.Your actual film usage, and then get your actual cost per package.

Film usage：

We need to know the following data first:

film length that you can get

Standard film length that you need

film cut-off

re-wrap percentage

Let's calculate

1. film length. divided by cutoff;

2. cutoff multiplied by re-wrap percentage;

3. rewrapped package subtracted from total;

4. Then get your film usage, Packages Per Roll!

Suppose you should pay $130 for each roll of film

5. Packages Per Roll. divided by 130

6. then multiplied by thousand, we get cost per thousand packages!

After knowing these data, you can contact suppliers of shrink film. Get new reserch and material, you may be surprised how much money can be saved with the smallest adjustments.

These are all you need to know about shrink film for packaging today. For more information and discussions on packaging machines and packaging materials, please check us frequently.