Check the boundary of the description
Identify the copper-to-dielectric interface described by the supplier. Coverlay, multilayer bonding, shielding, and stiffener attachment can still introduce adhesives elsewhere. Start with the ordered layer list in the construction drawing guide. This prevents a nominal base-laminate description from hiding thickness or process assumptions in later operations.
Review the actual adhesiveless construction
| Decision | Define | Review |
|---|---|---|
| Base interface | Supplier laminate architecture | No separate base adhesive assumed |
| Additional insulation | Coverlay film and adhesive | Complete finished thickness |
| Multilayer build | Bonding material and sequence | Compatibility through processing |
| Copper | Foil grade and plated contribution | Mechanical and electrical assumptions |
Use the construction to solve a stated problem
Compare candidate base laminates against thickness, electrical geometry, assembly exposure, and mechanical duty. Panasonic presents FELIOS as adhesiveless flexible circuit material with multiple film and copper options. Availability of a family does not establish that every desired combination is available for your build. Ask for the specific grade and construction, then compare the resulting total stack against the alternative.
Review what changes downstream
If the laminate replaces an adhesive-based construction, update dielectric spacing and local thickness calculations before preserving old trace dimensions. Revisit bonding and coverlay choices rather than assuming they stay suitable. The adhesive-based comparison helps isolate what is actually different. Use representative assembly and movement checks to assess the proposed finished circuit instead of transferring unrelated supplier coupon results.
Before you release the design
- Obtain a specific laminate construction.
- List adhesives still present elsewhere.
- Recalculate local stack dimensions.
- Review the changed geometry and qualification scope.
Watch points
- Adhesiveless does not mean immune to delamination or automatically suitable for any repeated bend.
Practical questions
Is the finished circuit always thinner?
Compare equal electrical and protection requirements. Removing one layer can help, but other construction choices determine the final total.
Does it remove stiffener adhesive?
No. Stiffener attachment is a separate material and process decision that must remain visible in the drawing.
Technical references
References support the material or design context. Check the exact grade, part number, document revision and project conditions before release.Updated 27 September 2026 · Technical content policy · Engineering guidance supports project review; the agreed drawing defines the build.