Mylar is a brand name for a type of strong, lightweight plastic film made from polyethylene terephthalate (PET). Mylar is widely used for packaging, insulation, electronics, thermal blankets, balloons, decorative ribbons, and many other applications due to its unique properties. It is an engineered plastic film designed for high performance across a range of uses. Die-casting also provides some surface finish.
Properties of Mylar
Here are some properties of Mylar plastic film:
- – Thickness: Mylar films are available in thicknesses ranging from 0.5 mils (0.0005 inches or 12 microns) to over 10 mils. Typical thickness is 1-2 mil for many applications.
- – Strength: Mylar has a tensile strength of 20,000 to 30,000 psi, compared to about 7,500 psi for polyethylene. This high strength allows very thin films to be used.
- – Temperature range: Mylar can withstand temperatures from -100°F to over 300°F (-73°C to 150°C). The melting point is 482°F (250°C).
- – Water vapor transmission: The water vapor transmission rate of 1 mil Mylar is 0.1 grams/100 sq. in./day, making it a good moisture barrier.
- – Oxygen transmission: The oxygen transmission rate of 1 mil Mylar is 3.4 cc/100 sq. in./day, providing a good oxygen barrier.
- – Chemical resistance: Mylar resists oils, greases, acids, alkalis, alcohols, hydrocarbons, and other chemicals. It is not affected by most solvents.
- – Dielectric strength: Mylar has a dielectric strength of >1500 volts/mil, allowing it to insulate wires and components.
- – Reflectivity: Some Mylar films have a mirrored coating with over 90% reflectivity in the visible light spectrum.
- – Durability: Mylar retains its properties after folding, creasing, or processing. It has good abrasion resistance.
Uses of Mylar
Here are some of the most common uses of Mylar:
- – For food packaging, major suppliers of Mylar pouches and bags include Packaging Technologies, IMPAK Corporation, Amcor, and Oliver Healthcare Packaging.
- – For balloons and decorative ribbons, major manufacturers are Anagram International, Tillys, Qualatex, and Betallic.
- – For insulation applications, companies like Reflectix, CS Hyde, and Lydall supply Mylar-based insulation products.
- – For electronics, Mylar polyester films are supplied by companies like DuPont, Toray, and Saint-Gobain.
- – Reflective Mylar for reflectors and blankets is sold by Reflectix, CS Hyde, SPACEWARP, and Dunmore.
- – For arts and crafts uses, Mylar sheets are repackaged and resold by many retailers like Uline, ClearBags, Nashville Wraps, and Paper Mart.
How To Use Mylar for Making Stencils?
Here is a step guide for using Mylar to make stencils:
- Step 1: Select an appropriate thickness of Mylar – 2-5 mil thickness works well for stencils. Thinner Mylar is prone to tearing while thicker is hard to cut.
- Step 2: Design the stencil pattern you want and print it out – Print the design in reverse (as a mirror image) so it will display properly when painting through the stencil.
- Step 3: Cut out the design from the Mylar – Use a very sharp X-acto knife and metal ruler. Cut on a self-healing mat to protect your work surface. Cut out small sections at a time.
- Step 4: Remove the excess Mylar – Carefully peel away the excess Mylar surrounding your cut-out design. This will leave just the stencil outline intact.
- Step 5: Attach the stencil to a stiff backing – Use spray adhesive to attach the Mylar stencil to cardboard, plastic, or wood. This gives it rigidity for easier handling.
- Step 6: Smooth out the edges – Lightly sand or use fine grit sandpaper to smooth any rough edges on the stencil. This creates a cleaner painted edge.
- Step 7: Perform a test spray – Try a test spray paint run on paper to ensure the paint will only go through the cutout sections. Adjust the design if needed.
- Step 8: Apply painter’s tape – Use tape to mask off any areas you don’t want painted. Tape the stencil down when spraying.
- Step 9: Spray paint through the stencil – Hold the stencil flush to the surface being painted. Apply several thin coats for a smooth fill.
- Step 10: Allow paint to dry before carefully removing the stencil.
- Step 11: Clean and store the stencil for repeated uses. Mylar stencils can be reused many times.
What Power Level Is Recommended for High-Quality Laser Cut Mylar?
As a general guideline, for thin Mylar sheets around 0.1 mm (100 micrometers) thick, a low to medium-power laser can be used, typically in the range of 10 to 40 watts. Thicker Mylar sheets, such as those around 0.25 mm (250 micrometers) or more, may require higher power lasers in the range of 40 to 100 watts or more.