What is Heat Shrinkable Packaging Film?

Introduction to Heat Shrinkable Packaging Film

Heat shrinkable packaging film is a thermoplastic film. Stretch and oriente during production and shrunk by heat during use. The heat-shrinkable film uses the energy in the film when the film stretching longitudinally or transversely in a highly elastic state. Utilize the memory effect of thermoplastics on the shape before bidirectional or unidirectional stretching. When heating again, it can restore the function of the shape before stretching to achieve the purpose of packaging.

Heat shrinkable packaging is a packaging method widely use in commodity packaging. It can pack various types of products, and has the characteristics of transparency, packaging, sealing, and moisture-proof. The process and equipment are simple, the packaging cost is low, and the packaging methods are diverse, so many merchants and consumerd favor it.

As manufacturers increasingly pursue product differentiation competition, the market develops rapidly for heat shrinkable film labels for packaging food, beverages and other consumer foods.

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What is the Production Process of Heat Shrinkable Film?

The production of shrink film usually adopts extrusion blow molding or extrusion casting to produce thick film. Then stretch longitudinally and transversely above the softening temperature and below the melting temperature at a high elastic state temperature. Or just stretch orientation in one direction and not the other.

The former film is biaxial stretch shrink film, while the latter is unidirectional shrink film. When in use, when the stretching temperature is higher than or close to the stretching temperature, the film’s shrinkage force will bound the packaged goods. The materials for heat shrinkable films are mainly various thermoplastic films.

How to Manufacture Heat Shrinkable Films?

The 3-layer co-extruded heat shrinkable packaging film uses PE and PP as the main raw materials. A new type of environmentally friendly and non-toxic heat shrinkable packaging material that producing by three-layer co-extrusion blow molding process.

The three-layer co-extruded heat shrinkable packaging film is mainly made of linear low-density polyethylene (LLDPE) and copolymerized polypropylene (TPP, PPC). Co-extrusion blow molding process by adding necessary additives is the way to produce this film. Its process is different from the traditional blow molding process. Due to the poor tensile properties of PP melt state, it can not take the traditional blow molding process, but the double-bubble process.

It melts and extrudes raw materials through different extruders, passes through a specially designed co-extrusion die head, forms a primary film, quenches it, and then heats it for a second blowing stretch to obtain a product.

What are Raw Materials of Heat Shrinkable Films?

The main raw materials of the 3-layer co-extruded heat-shrinkable packaging film include LLDPE (linear low-density polyethylene), TPP (terpolymerized polypropylene), and PPC (binary copolymerized polypropylene). And necessary functional additives such as slip agent, anti-blocking agent, antistatic agent, etc.

These raw materials are all environmentally friendly and non-toxic materials, no toxic gas and peculiar smell will be produced during the processing and product application, and the hygienic performance of the product meets the US FDA and European EU standards, and can use for food packaging.

What does the Heat Shrinkable Film Contain?

Initially, heat shrinkable packaging film was mainly PVC shrinkable film. Continuously developing with market demand, PVC shrink film is gradually decreasing in use. While various PE, PP, PET, PETG, PVDC, POF, PO and other multi-layer co-extrusion heat shrinkable films develop rapidly and become the mainstream of the market.

PVC Heat Shrinkable Film

PVC (polyvinyl chloride) heat shrinkable film is polymerized from vinyl chloride monomer into polyvinyl chloride resin. Then chemically modify the polyvinyl chloride resin. Blow molding or calendering are the production methods of PVC heat shrinkable film.

The production process of PVC heat-shrinkable film is as follows:

Unpacking of PVC resin raw materials, inspection, sieving, formulation, mixing, granulation, extrusion of thick film. Air cooling, heating in hot water bath with boiling water, horizontal blowing of the shaping cylinder, film clamping. Then defoam and roll into a PVC heat-shrinkable film.

PVC shrink film has good transparency and high shrinkage rate, between 40% and 60%. Moreover, its cost is low, its tensile strength is high, and its temperature shrinkage range is large. The requirements for the heat source are not high, and the main processing heat source is hot air, infrared rays, or a combination of the two.

PVC is a heat-sensitive plastic, and it is difficult to completely seal the shunt of the extruder with the body. Under the high pressure of more than 300 atmospheres, the PVC melt can easily enter the tiny gap between the shunt shuttle and the body, decompose and rupture the bubble film. It can solve the problem in this manufacturing process by using a material with good heat resistance and airtightness as the sealing material.

However, PVC shrink film is poor in environmental protection and difficult to recycle. This film will produce toxic gas during combustion. It’s not conducive to environmental protection. So, some countries, including Europe and Japan ban this packaging film. Moreover, the relative density ratio of PVC and PET materials is about 1 to 33. With the current state of the art, it is difficult to tell the two apart during the recycling process.

PVDC Heat Shrinkable Film

PVDC (polyvinylidene chloride) is a non-toxic, odorless, safe and reliable high barrier material. In addition to the general properties of plastics. It also has oil resistance, corrosion resistance, and taste retention. And excellent moisture-proof, mildew-proof, can directly contact with food and other properties.

It also has excellent printability. High crystallinity and high density determine that PVDC copolymer has good oxygen barrier, gas barrier and taste retention. Due to the symmetry of its molecular structure and the strong cohesion between molecules. It is difficult for oxygen molecules and water molecules to move in the molecule.

PVDC shrink film mainly using for packaging chilled meat. By using a vacuum packaging machine, to shrink wrap chilled fresh meat. Take advantage of its high shrinkage and high barrier properties. The packaged chilled meat products not only have a good appearance. But also can maintain the freshness of the chilled meat for a long time.

In Europe, America, Australia and other places, PVDC shrink film is widely using in packaging fresh beef products. Packaging fresh beef with it has become an irreplaceable way, extending the shelf life of fresh beef to a maximum of 2 months.

PET Heat Shrinkable Film

PET (polyester) film is an internationally recognized environmentally friendly heat shrinkable film material. Polyester heat shrinkable film is a new type of heat shrinkable packaging material. The main features of PET heat shrinkable film are: good shrinkage at low temperature, high shrinkage rate, fast shrinkage, non-toxic and low heat generation when burning.

PET heat-shrinkable film has excellent transparency, gloss and heat-sealing performance. And is suitable for high-speed packaging equipment. High shrinkage, excellent packaging effect. The density is small, the packaging cost is low, and can improve the economic benefit. Flexible and tough, high strength, will not harden and become brittle at low temperature.

Non-toxic and harmless, suitable for packaging of food and medicine. During heat sealing, no toxic gas. It has good barrier properties, excellent moisture resistance, has the advantages of static electricity elimination, and is not easy to be contaminated with dust.

PET heat shrinkable film can produce into heat shrinkable labels and envelopes through production and processing. It is widely use in the packaging and sealing of bottles, the insulation of electronic parts and batteries, heat resistance, and can effectively protect products. The shrink label is beautifully printed, does not fade, does not fall off, and is glue-free, which effectively improves the product image. But ordinary polyester is a crystalline polymer.

Ordinary PET film can only get a heat shrinkage rate of less than 30% after special processing. To obtain a polyester film with a higher heat shrinkage rate, must modify the film materials. That is to say, in order to make a polyester film with a high heat shrinkage rate, it is necessary to carry out copolymerization modification on ordinary polyester. That is, polyethylene terephthalate. The maximum heat shrinkage rate of the PET film after copolymerization modification can be as high as 70%.

At present, more and more packaging manufacturers use printed shrink film instead of traditional transparent film. Because the printed shrink film can improve the appearance grade of the product, which is conducive to the advertising of the product. And it can make the trademark brand leave a deep impression in the hearts of consumers.

PETG Heat Shrinkable Film

PET film is specially use in high-performance shrink film, with a final shrinkage rate greater than 70%. It can be made into packaging for containers with complex shapes. It has the advantages of high plastic absorption, high transparency, high gloss, low haze, easy to print, not easy to fall off, and low natural shrinkage during storage.

Among them, the biaxially stretched PETG film is suitable for high-end packaging, printing, electronic appliances, cable wrapping, insulation materials and high-quality substrates in various industrial fields.

Uniaxially stretched PET, heat shrinkable film is suitable for various cans, polyester bottles, various containers and other external labels. Generally, bottles with complex geometric shapes often choose PETG material as the label material. This is because PETG resin is beneficial to environmental protection, and its resin shrinkage temperature is lower than that of PVC and OPC.

Compared with other competitive materials, the temperature shrinkage of PETG is relatively stable. These properties make it possible to have more precise control over the thermal shrinkage of the labels in the hot tunnel. This makes it possible to obtain a PETG shrink label film with a specific gravity of less than 1. This ensures adequate separation of the shrink film from denser materials such as PET during bottle recycling.

OPS Heat Shrinkable Film

OPS heat shrinkable film (two-way stretched polystyrene heat shrinkable film), is a kind of body-fitting packaging material. It has high strength, high rigidity, stable shape, good gloss and transparency, and is easy to process. Easy to color, good printing performance, extremely low loss rate, and high resolution. For the constant pursuit of exquisite trademarks, it is completely a material progress.

OPS makes up for the defects of traditional inflation shrink film, and its transverse shrinkage rate can be as high as 80%. This kind of high shrinkage rate can make the trademark stick to the body on containers of different shapes to highlight the shape of the container. It makes the package more vivid, and can also achieve good effects of anti-explosion cracking and sealing and sanitation.

OPS can not only print exquisite patterns, but also meet people’s requirements for the use of various novel packaging containers with different shapes. The crystal point of OPS, commonly known as fisheye, is almost non-existent. As a result, the problem of lower yield due to crystal points has been brought to printing production, which has been fundamentally changed.

Because of its good flatness, it can completely change the problem that PVC heat shrinkable film can only be printed in narrow width in the past. It can meet the requirements of wide-format high-speed printing, improve efficiency, and help manufacturers reduce costs.

Since the OPS heat shrinkable film has almost no shrinkage below 60°C. A series of problems such as transportation, storage, packaging, and short validity period of the film can be solved during the use of the heat shrinkable film. It provides technical support for label printers, and also creates conditions for merchants to reduce costs.

Compared with PVC film, OPS film has the advantage of being reusable, and the used trademark can be incinerated. Because it is non-toxic and tasteless after incineration, it will not have any environmental pollution.

POF Heat Shrinkable Film

The full name of POF is multi-layer co-extruded polyolefin heat shrinkable film. It is made of ethylene/propylene copolymerized EPC, propylene homopolymerized PP, ethylene/propylene/butylene three-layer copolymerized EPB, and linear low-density polyethylene LLDPE as raw materials.

After a special production process, the inner layer, the middle layer and the outer layer are co-extruded to make a high-quality heat-shrinkable film. POF has all the advantages of polyethylene (PE) and polypropylene (PP) at the same time. Its excellent performance is far superior to pure polyethylene and polypropylene.

POF shrink films have the characteristics of non-toxic, environmental protection. High transparency, high shrinkage rate, good heat sealing performance, high surface gloss, good toughness, high tear resistance. Uniform heat shrinkage and suitable for automatic high-speed packaging. It is currently the most widely use and popular environmental-friendly heat-shrinkable hygienic packaging material in the world.

PO Heat Shrinkable Film

Environmentally friendly multi-layer co-extruded polyolefin (PO) heat shrinkable film is a widely to use environmentally friendly packaging material. Environmentally friendly multi-layer co-extruded polyolefin PO heat-shrinkable film is producing by three extruders at the same time, blown by double bubble method, biaxially stretched and then cooled and shaped.

Its two extruders uniformly extrude different raw materials through the co-extrusion laminated film head. To form a co-extruded film with three layers of inner, middle and outer layers of different material structures. The middle layer is linear low density polyethylene (LLDPE), and the inner and outer layers are copolymerized polypropylene (PP).

This 3-layer film combines the advantages of polyethylene (PE) and polypropylene (PP). The quality is better than pure polyethylene (PE) film, and also better than pure polypropylene (PP) film.

What are the Advantages of Heat Shrinkable Films?

Heat shrink film is an excellent film packaging material, it has the following advantages:

1. Beautiful Appearance, Adhere to Products.
Therefore, it’s another name is skin packaging, which is suitable for commodity packaging of various shapes.

2. Good Protection
It can pack a variety of commodities in a heat shrinkable bag. Prevent the loss of individual small commodities, and it is also convenient for customers to carry.

3. Good Cleaning Performance
Especially suitable for hygienic products, hotel supplies, cleaning products, paper products, food and other items that require hygienic cleaning.

4. Multipurpose
Select different resins and formulations can produce heat-shrinkable films with different mechanical strengths and functions. This film can use for inner packaging with low strength and small product weight. It can also use for transportation packaging, that is, outer packaging, for mechanical products use in containers and building materials that require high strength.

5. Good Anti-theft Performance
Multiple foods can pack together with a large shrink film to avoid loss.

6. Good Stability
The product will not wobble in the packaging film.

7. High Transparency
Allowing customers to directly see the packaged goods. It is convenient for customers to choose products.

8. Cost-effective
Heat shrinkable film packaging is often cheap and good quality.

Heat Shrink Film Label

Heat shrink film label is a film label to print on plastic film or plastic tube with special ink. During the labeling process, when the label is shrunk when heating, it will quickly shrink along the outer wheel of the container and cling to the surface of the container.

There are two types of heat shrink film labels: shrink sleeve labels and shrink wrap labels. Shrink sleeve labeling is a commonly used technology. The resins used in this sleeve label film are usually PVC, PETG and OPS.

Heat shrinkable labels are highly adaptable and can use for the packaging of food, beverages and other consumer goods. Heat-shrinkable labels are a part of the label market, which is growing rapidly and its market share is expanding. The latest research shows that the global heat-shrinkable label market is growing at an average annual rate of 10% to 15%, far exceeding the annual growth rate of about 5% in the ordinary label market. The development potential is huge and it has become the biggest bright spot in the label industry. Behind the strong demand, there are many advantages of heat shrinkable labels.

Shrink labels add eye-catching, quality-enhancing and overall decorative advantages to blow-molded plastic bottles or containers. Heat-shrinkable labels can be tightly attached to any irregularly shaped bottle, especially when the fit extends to the bottle neck cap, the label can significantly change the characteristics of the container. In addition, adding UV absorbers to the formula of heat shrink labels can also extend the shelf life of packaged items.

Heat Shrinkable Packaging vs Carton Packaging, Use and Cost Comparison, Which One is Better?

Heat shrinkable packaging is a very promising form of packaging. The biggest reason why heat shrinkable packaging technology is affirmed is that it can reduce costs, promote sales, and increase shelf display effects. Heat shrink packaging can generally reduce the cost by 70% compared to carton packaging. With the development of heat-shrinkable packaging technology and the continuous improvement of the pressure-bearing capacity of heat-shrinkable films, heat-shrinkable packaging machines can completely replace cartons in packages of certain specifications.

Commodity packaging is the largest market for shrink packaging. Heat shrinkable film is widely to use in the packaging of various industrial products, such as sanitary products, office supplies, cosmetics, stationery, toys, daily necessities, medicines, kitchen cleaning products, supermarket promotional items and so on. There are also many applications in the field of food packaging, such as baked goods, meat products, candy, chocolate, dairy products, beverages, snacks, etc.

In the field of toiletries, many products require to pack together. Such as shampoo and conditioner, hair dye and conditioner, etc. The disadvantages of the commonly used cartons such as high cost, low flexibility, and easy deformation have affected the development of cartons in the daily chemical market. And heat shrinkable packaging, its product display is intuitive, the packaging cost is low, and the packaging effect is beautiful.

Some companies only temporarily promote certain two or several products at a certain stage. Due to the relatively large randomness of this kind of promotion, it is not realistic to use carton packaging. With heat shrinkable packaging, companies can match several promotional products at any time according to the actual situation. Put it into the shrink furnace for simple operation. This brings great convenience to enterprises and avoids unnecessary costs.

POF Shrink Film Product Photo and Video

POF Shrink Film Manufacturer Supplier Factory

POF polyolefin shrink film manufacturer, Filmnpack, is a high standards heat shrink packaging material product supplier in China. As a leading polyolefin POF packaging film supplier, we have 10 advanced blown film production lines with an annual output of up to 16,000 tons. We’re dedicated to offering a wide range of high quality polyolefin POF plastic shrink films to meet the diverse needs of buyers’ bulk purchase. All our polyolefin film products have been quality certified by international standards to ensure stable and reliable quality. Additionally, we focus on competitive prices, giving you great value for money with our cost-effective polyolefin POF products.