What is Hologram Film Splicing?
Hologram film splicing is the process of joining the end of one roll of holographic film to the beginning of another roll, creating a single, continuous web. Splicing is essential for high‑volume converting operations – such as printing, coating, slitting, and die‑cutting – where stopping the machine to change rolls would waste time and material. A typical splice is made using specialised adhesive tape (splicing tape) or, in some cases, ultrasonic or heat welding. The splice must be strong enough to withstand the tension of the converting line, yet thin and smooth so it does not damage processing rollers or cause the web to break. Splicing is performed both on raw holographic film (before embossing) and on finished label rolls (during slitting or rewinding). Holoseal works with converting partners who use precision splicing techniques to ensure that your hologram label rolls have minimal waste and uninterrupted production runs.
🔍 Why Splicing Is Essential in Hologram Converting
- Continuous production – Splicing allows printing, coating, or slitting lines to run without stopping when a roll ends, maximising uptime.
- Reduced waste – Instead of discarding the tail of a roll, splicing connects it to the next roll, using nearly 100% of the material.
- Consistent tension – A properly executed splice maintains uniform web tension across the join, preventing breaks or misregistration.
- Minimised roller damage – Smooth, low‑profile splices prevent damage to expensive anilox rollers, dies, and pressure rollers.
⚙️ How Hologram Film Splicing Works (Step‑by‑Step)
The splicing process can be manual or fully automatic. Here is the typical workflow for manual splicing on a converting line:
1. Roll Change Detection
The converting machine detects that the current roll is nearing its end (via low‑diameter sensor or operator observation).
2. Web Stopping (or Flying Splice)
For manual splices, the machine stops. For advanced lines, a “flying splice” is performed at full speed using accumulator rollers.
3. Tail and Leader Preparation
The end (tail) of the expiring roll and the start (leader) of the new roll are cut cleanly at an angle (e.g., 30–45°) to increase the splice contact area and reduce thickness.
4. Splicing Tape Application
A thin, high‑strength splicing tape (double‑coated or single‑coated with a release liner) is applied to join the two ends. The tape must be compatible with the holographic film (PET or BOPP) and not leave residue. Tape thickness is typically 30–100 µm.
5. Pressing and Smoothing
The splice is pressed firmly to ensure good adhesion and remove air bubbles. A smooth, bump‑free joint is critical.
6. Restarting the Line
For manual splices, the machine is restarted. The accumulator (if available) releases stored web to match line speed.
📦 Types of Splicing Methods for Holographic Film
- Butt splice (tape on one side) – The two ends are butted together and taped on the non‑printing side. Common for thin films where a double‑sided splice would be too thick.
- Overlap splice (double‑coated tape) – The two ends overlap slightly (e.g., 5–10 mm) and are joined with double‑coated tape. Stronger but creates a thicker bump.
- Flying splice (automatic) – A high‑speed, automated splice made without stopping the line. Uses an accumulator to store web while the splice is made. Essential for high‑speed coating and printing lines.
- Ultrasonic or heat welding – For some thermoplastic holographic films, the ends can be welded using ultrasonic energy or heat, eliminating tape. Less common but useful for cleanroom applications.
🛡️ Quality Considerations for Splicing Holographic Film
- Tape selection – Use tape specifically designed for film splicing (e.g., 3M 93015LE, tesa 51970). It must have high adhesion to PET/BOPP, thin backing, and no adhesive bleed.
- Splice thickness – Should be less than 120% of the film thickness to prevent roller bounce. For a 50 µm film, the total splice thickness should be ≤ 60 µm.
- Edge alignment – The two edges must align perfectly (±0.5 mm) to prevent lateral wandering and edge damage.
- Air entrapment – Bubbles under the tape can cause localised thickness variations, leading to poor printing or die‑cutting.
- Hologram pattern continuity – For embossed film, the splice should ideally be placed in a non‑critical area (e.g., between label repeats). Splicing over a hologram can distort the pattern.
🔐 Challenges Specific to Holographic Film Splicing
Holographic film presents unique challenges because of its metalized coating and diffractive structure:
- Metal layer adhesion – The aluminium layer can flake if the film is creased during splicing. Splices must be made without folding or creasing.
- Static electricity – Holographic film generates static charge, attracting dust to the splice area. Use anti‑static bars or ionising blowers during splicing.
- Pattern registration – When splicing pre‑printed hologram rolls, the printed pattern may not align across the splice, but that is acceptable as long as the splice is flagged for removal later.
- Roller marking – A thick splice can leave impression marks on soft rollers or damage engraved cylinders. Always use the thinnest possible tape.
🌍 Holoseal’s Approach to Splicing
Holoseal does not perform splicing directly; we work with converting partners who operate modern splicers. For your hologram label orders, we coordinate:
- Minimising the number of splices per master roll (ideally zero, but sometimes necessary for very long runs).
- Using high‑quality splicing tape that is compatible with PET holographic film.
- Flagging splice locations on the roll so your automatic label applicator can reject labels affected by the splice.
- Ensuring splices are made outside the printable or die‑cut area whenever possible.
With 15+ years of experience, we ensure that splices do not compromise the security or performance of your hologram labels.
❓ Frequently Asked Questions About Hologram Film Splicing
- Can a splice be seen on the finished hologram label? – Usually yes – the splice creates a visible bump or line. For this reason, splices are placed in the waste matrix (between labels) or flagged so that affected labels are removed before shipping.
- Will a splice damage my automatic label applicator? – A well‑made splice with tape thickness less than the label + liner thickness should pass through most applicators without jamming. However, we recommend testing a sample roll on your machine.
- Is it better to have no splices at all? – Yes, splice‑free rolls are ideal. However, for very long runs (over 5,000 m of film), splices may be necessary because master rolls have finite length. Holoseal minimises splices wherever possible.
- What is the difference between a splice and a joint? – The terms are used interchangeably. “Splice” is more common in web converting.
- Can ultrasonic welding be used on holographic film? – Yes, for certain thermoplastic holographic films (e.g., BOPP). However, the metal layer may interfere with ultrasonic energy. Holoseal recommends tape splicing for most holographic materials.
- How to order hologram label rolls with minimal splices from Holoseal? – Specify your required roll length. We will advise on maximum roll sizes available without splices. For extra‑long rolls, we will discuss splice placement and provide flagged splice locations. Contact us for a quote.
