Ultra Thin Polyimide Tape

Ultra Thin Polyimide Tape Material: amber polyimide film backing Backing choices: 12.5um, 25um, 50um Adhesive: thin silicone adhesive or acrylic option Color: amber, clear amber, black optional Format: slit roll, sheet, kiss-cut roll, die-cut part Contact Us

High Temp Tapes Company is an ultra thin polyimide tape manufacturer for compact electronic assemblies where ordinary PI tape may add too much thickness. This tape is built with 12.5um, 25um, or 50um PI backing and a controlled 8um - 25um adhesive layer, giving a typical total thickness range of about 22um - 75um after sample confirmation. It is used for PCB masking, semiconductor-related masking, low-profile insulation, and small die-cut parts where flatness, clean removal, and edge accuracy are important.

Product Photos

Product Overview

Ultra thin polyimide tape is made for areas where a small change in thickness can affect fit, masking height, or insulation clearance. In compact electronics, a standard PI tape may work well for heat resistance but still create a visible step around pads, connectors, sensors, or fine component spacing. This thin construction helps reduce that step while keeping the heat resistance and electrical insulation expected from PI film.

High Temp Tapes Company produces this ultra-thin PI film tape with three common backing choices. The 12.5um backing is used when the lowest profile is required, such as narrow PCB windows or tight insulation gaps. The 25um backing is a balanced choice for PCB process masking, where handling strength and flexibility both matter. The 50um backing is selected when the part is slightly larger, needs easier removal, or requires a higher dielectric margin.

The adhesive layer is also an important part of the design. A thinner adhesive build can help reduce edge squeeze, adhesive transfer, and visible marks around the masked area. Typical adhesive thickness is controlled between 8um and 25um, depending on the selected adhesive system and sample test result. For solder mask, copper, ENIG, OSP, or gold-plated surfaces, we recommend checking actual boards instead of relying only on a flat steel test panel. After reflow, inspection should include residue, staining, edge lifting, shrinkage, and whether the tape stays flat after cooling.

Technical Data Sheet

Key Benefits

• 5um PI backing helps reduce height build-up around fine pads, small components, and connector areas.
• 25um backing gives a practical balance of flexibility, handling strength, and PCB masking performance.
• 50um backing provides better handling for larger die-cut pieces and applications needing higher insulation margin.
• Controlled 8um - 25um adhesive coating helps reduce residue and staining risk after reflow soldering checks.
• Typical peel adhesion of 3.5 - 7.5 N/25mm gives useful holding without making removal too aggressive.
• Thin silicone adhesive PI tape can be slit or die-cut into narrow strips, dots, washers, and pull-tab parts.
• Linered format supports kiss-cut rolls when repeated placement and stable pick-up are required.
• Narrow slit rolls can be checked for +/-0.2mm slit width tolerance, clean edges, and roll stability before use.

Applications

1. PCB masking near solder pads, test points, gold fingers, and connector zones
2. SMT masking during reflow soldering, wave soldering, and selective heat exposure
3. Low-profile insulation in compact electronic modules, FPC assemblies, and sensor components
4. Semiconductor-related masking trials for leadframe back-side protection or molding-adjacent temporary masking
5. Die-cut parts such as small dots, narrow strips, washers, windows, and pull-tab pieces
6. Protection of residue-sensitive areas where adhesive transfer or staining must be checked after heat
7. Temporary insulation where normal PI tape is too thick for the available clearance
8. Thin polyimide tape for PCB masking where clean edge definition and low step height are required

How Should This Thin PI Tape Be Checked After PCB Reflow?

For PCB pads, gold fingers, connector openings, and sensor areas, the tape should be checked after the real reflow profile used in production. A useful sample test looks at whether the edge remains flat, whether adhesive transfers onto solder mask, copper, ENIG, or OSP surfaces, and whether any staining appears after cooling. The surface should be smooth, dry, clean, and free from oil or flux residue before application, because poor wet-out can cause corner lifting during heating. For residue-sensitive assemblies, controlled adhesive thickness is often more useful than simply increasing peel strength.

What Affects Die-Cut Accuracy on Very Small PI Tape Parts?

For small PI tape parts used as dots, washers, narrow strips, connector masks, or pull-tab pieces, die-cut accuracy depends on more than the cutting tool. Part size, corner radius, backing thickness, adhesive coat weight, liner release, web tension, and matrix stripping can all affect the final edge. A typical die-cut tolerance of +/-0.1mm - +/-0.3mm should be confirmed by drawing and sample, especially for sharp corners, narrow bridges, or very small windows. For tiny kiss-cut parts, the liner should also be tested for pick-up speed, edge deformation, release stability, and clean removal. Thin rolls should be protected from edge compression, dust, humidity, and telescoping before converting.

FAQ

What thickness should be selected for thin PI tape?

12.5um backing is suitable for very tight insulation spaces, 25um is a balanced option for PCB masking, and 50um gives better handling strength and a higher dielectric margin. Final selection should be tested on the actual board or component.

Can this tape be removed cleanly after reflow?

Clean removal depends on adhesive type, adhesive thickness, reflow profile, dwell time, surface condition, and removal timing. We recommend checking residue, staining, adhesive transfer, and edge lifting on actual solder mask, copper, ENIG, or OSP surfaces before volume use.

Is this tape suitable for die-cut parts?

Yes. It can be supplied as narrow strips, dots, washers, connector masks, pull-tab parts, and kiss-cut rolls. Die-cut tolerance should be confirmed by drawing, part size, liner type, web tension, and sample validation.

How should thin PI tape rolls be stored?

Keep rolls in original packaging at 15C - 26C and 40% - 60% RH when possible. Avoid edge compression, dust, roll deformation, telescoping, and long exposure to moisture, because thin rolls are more sensitive to handling damage and tack change than standard thickness PI tape.