Overview

Continuous roll etching runs metal strip from reel to reel through lamination, exposure, development and etching without breaking the web. The strip is unwound under controlled tension, laminated with dry film resist, exposed through a rotating or step-and-repeat mask that is registered to the web edge, then developed and etched in a spray chamber before being stripped, dried and rewound. Because the web is never cut into panels, every part along the coil sees the same chemistry, the same dwell time and the same transport path, which is what makes pitch repeatable over hundreds of metres rather than over a single sheet.

The engineering problem in roll-to-roll work is not the etch itself but keeping the web stable while it is wet, hot and under tension. Tension is split into zones — unwind, process, rewind — so that the wet web in the etch chamber is held at low tension while the dry sections carry the tracking load. Edge guiding corrects camber and keeps the mask in registration, and the rewind tension is profiled to build a coil that will not telescope or block when the customer unwinds it on an automated line.

Parameter Window

• Available Materials: stainless steel 304/316L, copper C110, nickel 201, aluminum 1080, phosphor bronze, spring steel 301
• Material Thickness Range: 0.03–0.6 mm
• Tolerance: ±0.05 mm on profile, ±0.02 mm on repeat pitch over 300 mm, ±0.01 mm on strip thickness
• Minimum Feature: 0.08 mm slot and 0.12 mm hole at 0.05 mm strip; 0.2 mm at 0.3 mm strip
• Coil Format: width 20–400 mm, core ID 76 mm or 152 mm, OD up to 600 mm, coil length up to 500 m
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. Coil Incoming Check — Measure width, camber, thickness profile and edge condition; a coil with edge damage will track badly through the whole line.
2. Unwind & Tension Setup — Set unwind, process and rewind tension by strip width and thickness, with the wet section held at the lowest stable value.
3. Inline Cleaning & Lamination — Degrease and laminate dry film in line, controlling nip pressure so no bubble or wrinkle enters the etch chamber.
4. Registration Exposure — Expose through a mask locked to the web edge or to index holes, holding pitch to ±0.02 mm across the run.
5. Development — Develop in line and inspect the web at speed for incomplete opening before it reaches the etchant.
6. Spray Etching — Etch in a conveyorised spray chamber; web speed, spray pressure and etchant temperature set depth and sidewall quality.
7. Strip & Surface Finish — Remove resist, rinse, neutralise, then passivate or plate in line where the finish allows.
8. Rewind & Splice Control — Rewind at profiled tension, record splices and metre count, and label the coil with direction and lot data.

Core Advantages

1. No panel handling losses: The web is never cut and re-registered, so there is no per-sheet edge scrap and no handling damage between steps.
2. Pitch that holds over length: Registration against the moving web keeps part-to-part spacing stable for hundreds of metres, which matters for reel-fed assembly and press tooling.
3. Uniform etch along the coil: Every point on the strip sees the same spray and dwell time, so depth does not drift from the start of the coil to the end.
4. Designed for downstream automation: Parts can be supplied with index holes, on a reel, wound in the orientation the customer's feeder expects.
5. Higher material yield: Nesting along a continuous web uses the strip more efficiently than discrete sheets, and the trimmed edge is a single continuous scrap stream.
6. Scalable volume: Throughput rises with line speed rather than with tool cavitation. A continuous roll etching line therefore absorbs a demand increase without a new die or a new qualification cycle.

Typical Applications

• Battery and busbar connector strip: Etched copper and aluminum links supplied on reel for automated pick-and-place.
• EMI shield blanks: Fine-slot shield outlines in 0.1 mm stainless, wound on reel for in-line forming.
• Filtration and mesh bands: Continuous etched mesh strip for filter media and acoustic screens.
• Encoder and aperture bands: Fine-pitch slot patterns where spacing must repeat along the full coil.
• Terminal and contact strip: Pre-plated copper alloy strip etched to outline before a stamping or forming step.
• Gasket and seal bands: Long etched gasket profiles in 0.25 mm stainless or copper for continuous dispensing equipment.

Design Notes & Process Considerations

1. Directional tolerance: Etch depth and kerf behave differently along the web and across it; state which direction the ±0.05 mm applies to.
2. Camber allowance: Strip camber is inherited, not corrected, so specify the maximum camber per metre that the customer's tracking system can absorb.
3. Edge margin: Keep 2–3 mm of unetched margin on each edge for transport and guiding, unless the part runs edge to edge.
4. Index holes: If the customer's feeder uses sprocket or pilot holes, define them in the artwork; adding them later means a new mask.
5. Splice policy: Agree the maximum number of splices per coil and how they are marked, since a splice will stop an automated line.
6. Coil build: Specify core diameter, outside diameter, winding direction and interleaving. A continuous roll etching supplier that matches these to the feeder avoids a rewind step at the customer end.