3mil vs. 5mil PTFE: What’s the difference and which should I buy?

3mil vs 5mil PTFE: All Your Questions Answered

Two of the most common types of PTFE are 3mil and 5mil. MIL is a unit of measure that represents one one-thousandth of an inch (.001 in), so these measurements are nearly imperceptible to the naked eye. So what’s the difference, and why do we sell both at Essentialware?

When do you need 3mil vs 5mil PTFE?

Appearances aren’t everything. Despite a mere 2 one-thousandth of an inch difference, 3mil and 5mil sheets have largely different applications. The PTFE content as a percentage of the fabric is much greater for 3mil than it is for 5mil, but has a much lower tensile strength. So the 3mil will have really good release properties, but will wear much faster (tensile strength).

The 5mil is the industry standard for commercial food service applications, where high use and rigorous cleaning benefits from the thicker weave.

Industrial applications often —but not always— tend towards 3mil, for a variety of applications: gasket fill, dye sublimation, and even taping high voltage wires thanks to PTFE’s unparalleled dielectric coefficient (meaning it can store a lot of energy).

The benefits of each depend on application. In custom graphics work, sublimating dye onto t-shirts, totes, and other materials, 5mil PTFE is up to the task. It’s ideal for its potential to last dozens more presses than the 3mil fabric.

When can you use either?

The heat range for these products are the same whether you choose 3mil or 5mil, maxing out around 550F— well above the standard sublimation max of 400F.

In garment graphics testing, it was determined that the time taken to heat press is also the same, or negligibly small, between these two products. Industrial tapes can be purchased in either 3mil and 5mil, and both perform well in electrical applications.

What this means in practical terms is that switching between the 3mil and 5mil for most projects is not a problem– but one may serve you better.

What if I still have questions?

Let’s talk— you can reach us during business hours by calling 888-975-0405 or filling out our Contact Form. We’d love to help!