by Chris Jorgensen
During a meeting at IPC APEX EXPO 2017, members of the e-textiles industry approached IPC (Association Connecting Electronics Industries) to help achieve their goal of developing international standards for their burgeoning field. IPC standards are open international standards, meaning anyone can participate in the process and can influence IPC standards, and because of it, IPC has a global network in place for standards development.
The e-textiles industry had specific objectives for IPC:
- Form a new general committee under IPC’s standards committee structure
- Develop a specification for e-textiles materials
- Develop a guideline to bridge knowledge gaps, provide education and share best practices in e-textiles design and manufacture
- Provide additional educational resources
- Institute round robin data collection studies to establish reliability thresholds for materials and products
- Avoid duplicate efforts with other standards development organizations, especially regarding terms and definitions
Meeting of minds
Following that meeting, the IPC Technical Activities Executive Committee approved the formation of the D-70 E-Textiles Committee, and volunteers from that new committee immediately got to work. Their first task was to address the specification for e-textiles materials.
Over the course of two years, a team (A-Team) within the committee developed a working draft document on woven and knitted e-textiles materials for the full committee of more than 170 people to review and provide comments.
To develop the draft standard, the A-Team used feedback from the e-textiles supply chain to identify key performance characteristics for woven and knitted e-textiles as well as test methods the supply chain indicated it used to test against those characteristics. Using this feedback, and through dozens of web meetings, the A-Team developed a draft standard for full committee review, comment resolution and, finally, consensus ballot for publication as an international standard.
This collaborative effort resulted in the recent release of IPC-8921, Requirements for Woven and Knitted Electronics Textiles (E-Textiles) Integrated with Conductive Fibers, Conductive Yarns and/or Wires.
What the standard accomplishes
IPC-8921 establishes classifications and designations for woven and knitted e-textiles integrated with e-fibers, e-yarns and e-wires. It also standardizes key characteristics and durability testing as well as the industry test methods to be used to test against those characteristics.
Key characteristics include electrical resistance, electromagnetic immunity, thermal conductivity, coefficient of thermal expansion (CTE), specific heat capacity, thermal shock resistance, outgassing, glass transition temperature (Tg) and melting point. IPC-8921 also includes 20 new terms and definitions for e-textiles and establishes quality assurance provisions and test frequencies for specific characteristics.
Product designers and manufacturers now have a consensus industry standard for gathering comparative data between different materials and suppliers. Suppliers of those materials benefit from the standard because, rather than conducting specific testing for each of their customers, they can point to IPC-8921.
“When used as a benchmark of e-textile performance, products can be analyzed and compared for use in any application. Development expectations and outcomes can be shared between user and seller for transparency,” said Stephanie Rodgers, Apex Mills, co-chair of the committee that developed IPC-8921.
Future e-textile standards
Additionally, IPC-8921 has set the stage for several other new international standards projects proposed by the e-textiles industry:
- Guideline on connectors for e-textiles
- IPC Test Methods to fill test method gaps identified by the committee
- Standard for e-textiles wearables that can include characteristics and test methods consistent with IPC-8921
- Washability guidelines and requirements to support wearables
- Specification for conductive fibers, yarns and wires for e-textiles
- Design standard for e-textiles-based printed electronics
- Specification for high-power applications for e-textiles (i.e., automotive applications)
In addition to these projects, the IPC D-70 Committee will begin to identify round robin testing needs (e.g., washability, stretchability, abrasion) to support standardization efforts.
Building e-textile consensus
Industry stakeholders are encouraged to participate in the IPC process. To join a working group or propose a new project, e-mail ChrisJorgensen@ipc.org or attend the next IPC E-Textiles Committee meeting Feb. 5 during IPC APEX EXPO in San Diego. Purchase IPC-8921 at https://shop.ipc.org/IPC-8921-English-D.
IPC, the Association Connecting Electronics Industries, is an industry association for printed circuit board and electronics manufacturing service companies, their customers and suppliers. Chris Jorgensen is the director of technology transfer, IPC.