What is shrink wrap?
Shrinkwrap, also known as shrink film, is a versatile polymer material used to wrap finished products. When heat is applied to shrink wrap, the film shrinks tightly around the wrapped item, creating a clear and strong protective barrier. Not only does it protect the product, but it also enhances its appearance and durability.
What types of shrink films are available?
Shrink film is a versatile polymer material used to package various products. The main types include polyolefin (POF), polyvinyl chloride (PVC) and polyethylene (PE). Each type has unique properties, advantages and disadvantages for different applications.
Polyolefin Shrink Film
Polyolefin Shrink Film mainly comprises polypropylene (PP) and linear low-density polyethylene (LLDPE). It has a crystal clear appearance and good durability for applications requiring high-quality packaging, such as the food and beverage industry.
Advantages:
– High transparency: allows a clear view of the contents, suitable for applications where products must be displayed.
– Low coefficient of friction: Easy to handle and used in various automated packaging equipment.
– High strength: excellent tensile strength and tear resistance to protect products during handling, storage and transportation.
– Puncture resistance: Packaging items with sharp corners can also remain intact.
Disadvantages:
– Higher cost: Due to its excellent properties, polyolefin shrink film is more expensive than other shrink films.
– Temperature limitation: It has a shrinkage value of about 20 degrees Celsius compared to PVC shrink films.
PVC Shrink Film
PVC (polyvinyl chloride) shrink film is a lightweight, low-cost, easy-to-use shrink packaging material. However, it has been replaced by polyolefin and polyethylene films in many applications over time.
Advantages:
– UV resistance: excellent resistance to UV rays, suitable for outdoor and sun-exposed environments.
– Resistant to acids, alkalis and chemicals: able to resist corrosion from a wide range of acids, alkalis and mineral chemicals.
– Low cost: low production cost, widely used in various packaging situations.
– Good electrical insulation: suitable for applications requiring electrical insulation, such as wire and cable wrapping.
– High transparency: Good transparency shows the appearance of the product.
– Good heat sealing performance: easy to perform heat sealing operations.
Disadvantages:
– Harmful gas emission: Hydrogen chloride gas is released during sealing, which harms health and requires a well-ventilated environment.
– High storage requirements: Special storage conditions are required to maintain performance.
Polyethylene Shrink Film
Polyethene (PE) shrink film is a durable packaging material commonly used to wrap products such as beverage bottles, hand sanitizers and cans. It can be categorized into different types, such as Low-Density Polyethylene (LDPE), Linear Low-Density Polyethylene (LLDPE), Medium Density Polyethylene (MDPE) and High-Density Polyethylene (HDPE).
Advantages:
– Protective: Provides good protection against tampering and blocks out dust and moisture.
– Highly flexible: suitable for a wide range of products and able to be wrapped according to the product’s shape.
– Highly transparent: makes it easy for consumers to view the product inside the package or helps to check stacked goods.
– Low cost: less expensive as a general-purpose material.
Disadvantages:
– Heat sensitive: not suitable for use in heat sensitive products, which may be damaged.
– Environmental impact: despite polyethene’s low carbon footprint, recycling options are limited and may lead to landfill disposal.
The difference between plastic wrap and shrink wrap
Plastic wrap, also known as cling film, is often used to provide a thin layer of protection for products that need it. It is manually wrapped around the item and does not provide a seal. Shrink wrap, on the other hand, is used to protect products from tampering and external elements by shrinking them tightly through heat after they are fully wrapped, ensuring product quality.
Difference between Polyolefin and Polypropylene?
Polyolefins are a broad category that includes a variety of polymers, the most common of which are polypropylene (PP) and polyethylene (PE). Polypropylene is a type of polyolefin, but it is stiffer and has better heat resistance than polyethylene. Polyolefin shrink film will often contain both PP and PE, utilizing the benefits of both.
What is the difference between polyolefin and PVC?
Polyolefin and PVC differ significantly in several ways. Polyolefin is more durable and environmentally friendly because it is chlorine-free and does not release harmful gases when heated and sealed, while PVC, while less costly, releases hydrogen chloride gas at high temperatures, which is harmful to health and is unstable because it becomes brittle at low temperatures and soft at high temperatures.
Polyolefin can be used for food packaging?
Polyolefin materials can be used for food packaging and are one of the preferred materials in the food packaging field. This is mainly because polyolefins have the following advantages that make them ideal for food packaging applications:
Safety: Polyolefin materials are FDA-approved for direct food contact. It does not contain harmful chemicals such as BPA and phthalates, ensuring the safety of packaged foods.
High transparency: Polyolefin shrink film has high transparency, clearly displaying the food inside the package and enhancing the product’s visual appeal. This is especially important for products that need to show the appearance of food, such as vegetables, fruits, meats and frozen foods.
Good sealing: Polyolefin shrink film has excellent sealing properties, which effectively prevents outside air and contaminants from entering the package, keeping the food fresh and hygienic.
Durability: Polyolefin materials are tear and puncture-resistant, and even food products with irregular shapes or sharp corners can be well protected. This is especially important for packaging foods that are easily damaged, such as cookies, bread and pizza.
Environmentally friendly: Polyolefin materials are recyclable, and the use of polyolefin packaging helps reduce environmental pollution. In addition, polyolefin shrink film does not release harmful gases during production and handling, making it more environmentally friendly.
Wide applicability: Polyolefin shrink film is suitable for all kinds of food packaging, from fresh food to processed food. It performs well in both frozen and ambient environments, maintaining its packaging performance at many temperatures.
What shapes are available in polyolefin shrink packaging?
1. Single Wound Film
Uses:
Single product packaging: used for wrapping individual products, such as books, DVDs, and cosmetic cases.
Bundle Packaging: you can combine several small items for easy transportation and sales.
Advantage:
High transparency: better show the appearance and details of the product.
Strong toughness: can protect the products better.
2. Center Fold Film
Uses:
Food packaging: suitable for frozen food, snacks and other packaging.
Advantage:
Easy to operate: Center Fold Film makes the packaging process easier; just put the product into the Center Fold Film and then heat shrink it.
Adaptable: Can be used for products of different sizes and shapes.
3. Tube Film
Usage:
Packaging of long products: such as pipes, wooden bars, steel bars and other long products.
Packaging of large items: suitable for packaging of large products such as furniture and home appliances.
Advantage:
Omni-directional protection: Tube film can completely wrap the product and provide complete protection.
High Strength: Suitable for packaging heavy products to prevent damage during transportation.
4. Shrinkable Bag
Uses:
Gift Packaging: suitable for gift boxes, toys and other packaging.
Food Packaging: for the freshness packaging of fruits and vegetables, bread and other food.
Advantage:
Convenient and quick: just put the product into the bag and heat shrink to complete the packaging.
High Transparency: Showcase the products and enhance the visual appeal of the goods.
5. Tow Ends Open Bag
Uses:
Packaging of large items, such as furniture, home appliances, etc.
Construction Material Packaging: for packaging bricks, tiles and other building materials.
Advantage:
Easy to handle: easy to load and remove products, especially suitable for large items.
High strength: provides sturdy protection against product damage.
6. Arc Shape Bag
Uses:
Gift Packaging: for packaging specially shaped gifts.
Particular Shape Product Packaging: for non-regular shaped items, such as curved products.
Advantage:
Unique design: the Arc Shape Bag can perfectly fit irregularly shaped products and make the package beautiful.
Does polyolefin contain BPA?
Polyolefins do not contain BPA (bisphenol A), phthalates, heavy metals, or toxic chemicals. In addition, no primer is required during application, thus avoiding the generation of volatile organic chemicals (VOCs).
Are polyolefins dangerous?
Polyolefin itself is a very safe material with no potential health hazards. Polyolefins include polyethylene (PE) and polypropylene (PP), which are commonly used in various applications such as food packaging, medical devices, and packaging for various consumer products. They are safe in the following ways:
Non-toxic: Polyolefin materials are free of harmful chemicals such as bisphenol A (BPA), phthalates, and heavy metals, which can be hazardous to human health in some plastics.
Stability: Polyolefin materials are very stable and do not release harmful gases or chemicals. Even during heat sealing, polyolefins do not produce harmful volatile organic compounds (VOCs), which are not harmful to the environment or health.
Recyclability: Polyolefin materials are recyclable, which reduces environmental pollution. Many companies are recycling and reusing polyolefin materials, significantly reducing the environmental impact of plastic waste.
Is PVC shrink film safe for food?
There are many factors to consider regarding the suitability of PVC (polyvinyl chloride) shrink film for food packaging. While PVC shrink film has some advantages in some specific application scenarios, it is not the best choice for food packaging for the following reasons:
Release of harmful chemicals: PVC shrink film releases hydrogen chloride gas (HCl), a harmful volatile organic compound (VOC), during the heating and sealing process. This gas is harmful to factory production workers and can pose a potential health risk to consumers. PVC shrink film often contains phthalates (phthalates) as plasticizers, chemicals that can penetrate food and pose a threat to human health.
FDA and Regulatory Restrictions: While some PVC formulations are FDA (U.S. Food and Drug Administration) and kosher-certified for use in food-contact applications, these formulations must be used cautiously in food packaging. There are many regulatory restrictions on using PVC in food packaging, and the regulatory requirements vary from country to country and region to region.
Environmental impact: PVC shrink film significantly impacts the environment during production and disposal. The production process requires the use of large quantities of chlorine gas if the waste incineration will produce toxic gases. In addition, PVC recycling is also relatively difficult; improper handling may lead to environmental pollution.
Alternative materials: For the above reasons, many food packaging companies are gradually using polyolefin (Polyolefin) shrink film to replace PVC shrink film. Polyolefin shrink film does not contain chlorine and harmful plasticizers, will not release harmful gases when heated and sealed, and, after FDA certification, can be used directly for food contact. Polyolefin shrink film is also superior to PVC in terms of transparency, durability and environmental performance, making it a safer and more reliable food packaging material.
How do I use shrink wrap?
Using shrink wrap is a two-step process. First, the product is wrapped in shrink wrap. Then, the heat is increased to make the film shrink tightly and wrap the product, thus completing the packaging process.
With the above-detailed introduction of polyolefin, PVC and polyethene, we can better understand their advantages and disadvantages in different applications and choose the right packaging material to ensure product safety and quality.