Mylar Bags: What Are They and How Do They Work?
Picture this: shiny helium-filled balloons, space blankets, emergency blankets, equipment labels, solar filters, and long-term food storage resealable plastic bags. If you’ve used any of these materials before, you’ve probably used Mylar.
So, what exactly is Mylar?
This polyethylene film is made from stretched polyethylene terephthalate (PET), otherwise known as biaxially-oriented polyethylene terephthalate (BoPET).
First developed in the 1950s by DuPont Hoechst, Mylar is produced by vaporizing aluminum inside a vacuum chamber that is then bonded to a polyester sheet to create PET.
PET is then placed on a roller and stretched by a particular machine biaxially in one direction and then in the transverse direction. The film is kept under tension at a temperature above 200 degrees, and the resulting film is the smooth BoPET.
What Is Mylar Used For?
There is a lot that this material can do both at home and commercially, like storing emergency food. For instance, Mylar is durable but flexible, making it perfect for packaging materials. The same properties make it an excellent material for solar technology and electrical insulation.
Mylar is also strong and can offer a great shelf life. The transparent film resists moisture, acids, and oils, thus, maintaining the integrity of documents excellently. This is why the US Library of Congress uses Mylar to preserve essential records.
And did you know that the average consumer prefers to use Mylar as a decorative piece for gifts because of its shiny and transparent appearance? In a word, high-quality Mylar is the most used and recognized polyester film on the market. Knowing that, here are some of its common uses to date:
Mylar Bags
Let’s break down the use of Mylar bags for prepping and storage, especially in the food industry. Mylar is the preferred storage option because it’s food-grade safe and perfect for preserving dry and low-fat foods like flour, rice, and beans.
This food saver is less permeable to gasses than other plastics, and it protects food from moisture and gas – especially oxygen. It keeps food fresh and healthy when used as a laminate – some foods can last as long as 25 years when stored correctly using Mylar bags.
However, you shouldn’t store some foods in Mylar bags for more than five years. This list includes dry and dehydrated food like pearl barley, brown sugar, whole wheat flour, brown rice, granola, chips, and dried meat. Dried eggs, nuts, seeds, milled grains, and other fresh or wet food products should not be stored for an extended period in a Mylar bag.
The only disadvantages of using Mylar bags as food storage bags are that they are not rodent-proof and susceptible to botulism bacteria because they grow in an environment with low oxygen, like a Mylar bag. So, ensure you pack food with 10% or less moisture when using a Mylar bag to keep your food edible.
If you are using oxygen absorbers, ensure you store moist foods for a short period. You can tell that your Mylar bag has bacteria if it bulges.
Another vital thing to consider is the quality of the Mylar bag or Mylar pouches. Usually, Mylar pouch bags are priced based on the thickness of the film (in mils or gauge), as well as the dimensions of the pouch.
The recommended thickness for a quality bag should range between four and six mils, especially if you want to package heavy-duty dry goods in smell-proof bags for an extended period.
Mylar Product Labels and Tags
Mylar tags, stickers, and labels could be the best because they are durable, flexible, stable, resistant to solvents and abrasion, and transparent. Additionally, they thrive well in harsh conditions, and their resistance to oil and other liquids makes them easy to clean.
This is why Mylar tags and labels are primarily used for outdoor purposes. You can also customize these tags and labels based on your preferred color and thickness or make them in 3D. The colors include matte, transparent, clear, pigmented, and brushed metalized.
Screen printing, doming, and digital printing are processes used to create Mylar labels and tags. When choosing a Mylar label, ensure that it is UL-approved, especially if the label is for your house or office building.
UL approval means that the labels have cautionary advisories or warnings for safety reasons. This is especially important for nameplates and labels on light bulbs, control panels, standing light fixtures, cooking equipment, and office furniture.
What Else Is Made From Mylar?
Insulation
Mylar is reflective like aluminum foil, which gives it a dull and shiny side. It reflects up to 99 percent of light and is less permeable to gasses, perfect for insulation. Depending on the weather condition, you can take advantage of the shiny and matte black dark side when insulating structures with Mylar.
For instance, if you are in a cold environment., insulate the structure with the shiny side of the Mylar material facing inward. It will reflect any escaping heat and keep your interior warm. But if you are in a warm environment, keep the reflective surface outside to reflect the heat from the sun and keep the interior cool.
Packaging
Mylar film is commonly used to make packaging bags like roasting bags, coffee foil pouches, and lids like yogurt lids in the food industry. Mylar provides unmatched barrier properties, a flexible surface, and high resistance to punctures as a foil bag.
This makes the film ideal for pharmaceutical products, tissue samples, and seeds, mainly because they are all sensitive to changes in oxygen and moisture in the environment.
Emergency Blankets
The reflective emergency blankets used to reflect body warmth to an individual are made using Mylar. Hence, they are a perfect addition to your outdoor survival kit and for shock victims. Marathon runners also use these blankets to keep their temperatures warm after running.
Hydrogenic Gardening
Hydrogenic gardeners cultivate plants indoors using water enriched in nutrients with metalized Mylar sheets fixed on the walls near the gardening system. The sheets reflect any wasted light to the plant, ensuring the lighting efficiency of the indoor garden is improved so that the plants can grow faster.
Musical Instruments
The thin material covering either one or both ends of an open drum is often Mylar. Stretching Mylar over the drum’s edge produces a tone, pitch, and consistency for music.
Other Industry Uses
- Mylar is coated and laminated with specific adhesives to create a scratch-resistant and protective film used in window applications.
- Mylar is used in stamping various foils because of its reliability
- The stability and strength of the product make it excellent for creating labels
- One of the most common uses of Mylar is the Mylar tags, which are preferred because of their resilience in harsh conditions.
Is Mylar the Same as Aluminum Foil?
The two are different but can be fused for specific uses like making balloons by adding aluminum to Mylar in small amounts to retain the flexibility of its plastic material, perfect for stand-up pouches. Both materials are also used for food packaging, vacuum bags, storage, gift wrapping, decorations, packaging, and foil containers.
Nonetheless, both Mylar and aluminum have specific areas of preference when considering their use applications. For instance, Mylar is used to apply clothing styles like lingerie and plastic ribbons and fusing objects.
Where aluminum is a better choice than Mylar includes situations where heat is necessary, like industrial or household settings. Mylar is a polyester resin melted and stretched into thin sheets in terms of properties.
On the other hand, aluminum is made from melted, mixed, and electronically reduced bauxite ore that’s removed oxygen from the metal. The metal is then pressed into thin sheets called aluminum.
Mylar Is More Flexible Than Foil
Foil is undeniably the best barrier for oxygen and moisture, but it is expensive, it cannot be heat sealed without a laminate applied, and it’s prone to cracking with use. Mylar is much more flexible, will not tear easily, and has excellent barrier properties (much less effective than foil), but it’s extremely common and economical.
Mylar Can Fuse with Other Objects
Mylar is an excellent material for molecular bonding because it is flexible, has tensile strength, and takes the characteristic of the bonded material. Also, Mylar remains flexible even when bonded with other materials.
But you will need to choose your adhesive carefully depending on your desired outcome. For instance, if you want an excellent peel strength, your adhesive will be different from if you want the materials to stick together permanently.
Some of the materials you can fuse with Mylar include glass, plastic, wood, rubber, vinyl, silicone, carbon fiber, marble, slate, PVC, and Fiberboard. It is also possible to bond Mylar to itself or a surface.
To attach Mylar to a surface, start by roughing up the surface and Mylar with sandpaper. Clean and remove any residues on the surface with a soft cloth and then add adhesive on the surface and leave it to set up for at least 30 seconds.
Both the surface and the Mylar should have a temperature of at least 120 degrees. Then firmly press the Mylar on the surface, starting with the middle and moving towards the edges. This ensures that no air is trapped in between the surface and Mylar. Press for 15 seconds and spray the seam to seal the two.
Is Mylar Better for Child Resistance?
The concept of child-resistant Mylar bags started when parents realized that children could easily open the initial Mylar bags.
Today, these bags are either made as non-reusable or reusable Mylar bags. Non-reusable bags are best used for products with a single serving since the bags cannot be used more than once due to the permanent sealing.
The bags are made child-resistant with a sealing mechanism combined with a heat-sealing section that should be bent and torn to open and at a specific section. On the other hand, the reusable Mylar bags have a flexible opening mechanism, perfect for reuse.
Pull Tab Press to Seal Zipper Bags
These are the most sought-after bags in the market because of the zipper mechanism and ease of use. Pulling on the back outer tab while holding the top of the front side releases the locking mechanism easily, however the complexity makes it harder for children to open the thump-pocket zip-seal Mylar bag.
Zipper Bags
These premium Mylar bags have a simple zip and lock at the end. Close the zipper, place the hock in the lock, and seal the bag. Some zipper mylar bags also have an extra polymer layer covering the locks and the zipper. You’ll need to apply some pressure to unlock the structure.
Push Pin Type Bag
While it looks like a standard zipper bag that opens and closes using a small zip at the upper end, this bag differs in that the zip gets locked once you close the packet. You need a small pin to lift the lock and open the packet.
Pinch Type Bag
This might be the least secure bag on the list, but the bag still has a locking mechanism that requires pinching on the marked surface to open.
Can You Store Cannabis in Mylar Bags?
Yes. Mylar bags are excellent for storing cannabis because they keep away the moisture, heat, light, and air that usually degrades the potency and the quality of cannabis buds. The Mylar bag seals your cannabis away and maintains its integrity, albeit at an affordable cost.
Other properties that make Mylar bags excellent for storing cannabis are durability, reusability, and resistance to toxins, odor, and tear. These barrier bags could be perfect for storing cannabis both short-term and long-term.
Mylar bags also check the three boxes required for ensuring compliance when storing cannabis products: child-resistant, smell-proof, and tamper-proof.
The Bottom Line on Mylar Bags
Mylar bags are fantastic for storing your foods, whether long-term or short-term and come in a bag size sure to fit your needs. The low oxygen transmission rate and the thickness of the foil laminate layer offer your food three layers of protection from odor, moisture, and light.
Additionally, Mylar material is flexible, durable, thin, and resistant to tear, perfect for long-term use and reuse.
You don’t have to worry about your food’s nutrients because the baggies seal and preserve everything properly. So, check out our selection of wholesale mylar bags and keep your food fresh and healthy longer with Dymapak today!
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