Flex & Rigid-Flex Circuit Capabilities

Below are our flex and rigid flex circuit capabilities, along with available materials substrates and adhesives. We also offer an extensive range of solder mask and coverlay products as well as various surface and finishes treatments.

Flexible Circuit Board Capabilities

Our Capabilities Include

  • Single or Double Sided Flex: Polyimide
  • Multilayer Flex up to 8 layers
  • Multilayer Rigid-Flex up to 20+ layers (rigid area)
  • Lines and Spaces: down to 0.003"
  • Installation of Connectors, Pins, Contacts, etc.
  • SMD & PTH Component Assembly available
  • Stiffener Supported Areas (using FR-4, Polyimide, etc.)
  • Blind & Buried Vias
  • Controlled Impedance
  • Selective Adhesives, PSAs and Thermally bonded
  • EMI / RF Shielding: Copper, Silver Ink & Shielding films
  • Circuits up to 24" in Length or Greater Depending Upon Technology

Flexible Circuit Materials


  • Polyimide: 1 – 3 mil
  • Epoxy
  • Teflon
Flexible Circuit Board Materials


  • Rolled Annealed Copper
  • Electro - Deposited

Flex Circuit Adhesives

  • Modified Acrylic
  • Modified Epoxy
  • Pressure Sensitive (PSA)

Solder Mask / Coverlay

A coverlay serves as the same function as soldermask that is used on a rigid printed circuit board. The difference with a coverlay is the added element of flexibility and durability it provides to the flexible circuit board.

  • Polyimide Coverlay: 1/2 mil to 2 mil
  • Flexible Liquid Photoimagable (LPI) Soldermask

See our blog post titled what is a flexible circuit coverlay to learn more.

Surface Treatment & Finishes

  • ENIG (Electroless Nickel - Immersion Gold)
  • Immersion Silver
  • Hard Gold
  • HAL (Non-leaded, RoHS)
  • HAL (Leaded)


Stiffeners are typically used to reinforce selective areas of flexible circuitry for component support, durability and mounting. They can also be used for strain relief and heat dissipation. Bonding materials include pressure sensitive adhesive (PSA) and Temperature sensitive adhesive (TSA).

Stiffener Materials:

  • Unclad FR4 / G10
  • Polyimide

Stiffener thickness is determined by your actual needs. Typical stiffeners thickness' range from 0.005" to 0.062".

Celebrating 65 Years of Manufacturing Excellence  Learn More →
America's Oldest. A History of Innovation.

Today at Epec, the customer comes first, and everything we do must be put through that filter. Whether it is developing e-commerce platforms to make it easier to work with us, or creating a NPI (new product introduction) process that helps our customers get to market faster, or the other 10 new projects we have in process, we must focus on building the new. By doing that every day, and by always making the customer our top priority, we plan on being here for another 65 years and then some.

Learn more about our 65 year story →

Celebrating 65 Years - Epec Engineered Technologies