One of the most frequent questions we get about smart fabrics is “can I wash it?”. Sometimes companies provide a yes, or a no, but truthfully, the answer is not that simple. Sometimes a “yes” can mean that you can wash it by hand and hang dry. Sometimes a “no” may mean washing causes too much damage for one use case, but not the one you’re looking for. Either way, a binary answer may be misleading.
To explain washability for smart textiles, we should first talk about washability for traditional fabrics. Most textiles degrade with every laundering cycle until the colour or fabric is so worn that the garment no longer “works”. Generally, a sign that a fabric has been over-washed is loss of elasticity, change in dimensions, faded colours, or holes. The main point here is that nothing can be washed forever with no degradation.
“An e-textile’s degradation should be measured through the change in conductivity, and electrical resistance.”
Similarly, E-textiles or smart fabrics will degrade with each washing cycle. The question is, how much can it be washed and at what setting until the e-textile will no longer serve its original purpose? Since colour and elasticity don’t generally determine an e-textiles function when washing-cycles are taken into account, we must understand its degradation with another measurement.
An e-textile’s degradation should be measured through the change in conductivity, and electrical resistance. You can measure this with a machine called a multimeter, which will deliver resistance in a unit called ohms. All you need to know is that higher reading shows less conductivity. Depending on the use case, a loss in conductivity may or may not have an impact on the function – this is where washability gets specific to the use of the e-textile.
While we all love to wash everything on cold and tumble dry low, care instructions can become very important for washing an e-textile. A standard wash cycle vs a delicates wash cycle can be 3x as fast, causing more damage. To understand what all the cycle settings on your washing machine really mean, AATCC’s 135 standard is a great place to reference and use as a basis for any testing.
Overall, next time you see an electronic textile product, don’t ask “ is it washable”, ask “ how much does it degrade after how many cycles and at what setting?” This information can help you decide what smart fabric technology is a good fit for your use case.