What is A Kiss Cut?
“Kiss Cut”, that’s an unusual term for any industry, but it explains the process used in laser cutting services that provide this type of cut. A kiss cut is a way to provide precision cut 2D components on an adhesive backed substrate. Unlike traditional cutting that cuts all the way through the material. Kiss cutting is done when the designed flat parts will be applied as needed by the requester or third-party manufacturers. The result of this process is that the parts can be peeled off and used when needed, so the results are like precision stickers. This technique is often done with ultra-thin materials in thicknesses between 0.0254mm to 0.203mm and applied to an adhesive backed substrate. Polyimides, Peek, mylar are just some of the types of materials used for kiss cutting projects. To make it a kiss cut requires knowledge of the materials and adhesives being used, which in many cases are acrylic or silicon based. Unlike a through cut, the process involves the laser parameters or “tool” to be adjusted. These tool settings include laser energy or wattage, laser passes, laser frequency, laser focus, dwell time, and laser speed (how fast is the laser head moves across the substrate). For example, a three-layer substrate consisting of a 5-mil thick Kapton sheet with a 1 mil adhesive layer, and a release paper liner can be kiss cut. The laser tool is adjusted to cut through the Kapton and adhesive, but not through the paper liner. The laser beam just “kisses” the liner but leaves it intact. Along with other settings, this combination of parameters can give customers the ability to use these types of precision parts, (shims, gaskets, spacers, thermal shields, and others), for specific applications, while being very precise in the geometry.
What Is the Difference Between Kiss Cutting and Die Cutting?
The main difference between kiss cutting and die cutting is that laser technology uses a beam of intensified light energy to cut and die cutting uses a hardened tool or “die” to cut the material. Results of a laser kiss cut part, and a die cut part would be hard to tell from a casual observation. However, under magnification, there are some significant differences like edge quality and dimensional tolerances, that can determine the best method to use that will benefit the end user’s application. The following table highlights these differences:
| Feature | Laser Kiss Cut | Die Cut |
|---|---|---|
| Edge Quality | Clean, precise, and burr-free. Can have some discoloration on the cut edge. Walls are straight. | Clean, but potential for burrs depends on material and die quality. Materials cut edge can be rounded from the die pressure. |
| Cost | Can be lower costs especially for R&D and low volume. Multi-iterations possible with no extra cost for laser tool. Higher volume not as fast or competitive. | Higher upfront cost for tooling, with lower volume production costs. Iterations require new die. |
| Set-Up | Process involves placement of materials on laser bed and import of data files. Laser tool adjustment needed. | New die needs to be created. Once available, set up of machine and parameters. |
| Turn Time | Faster turn time generally. Good for R&D and development projects and low to mid-level production volumes. | With new dies, the initial time is longer. Once in hand, the speed of processing can be fast. Good for high volume production. |
| Tolerances Held | Laser technology can hold tolerances from a +/- 0.0127mm to 0.0508mm | Die cutting tolerances held to +/- 0.127mm to 0.254mm |
| Materials Processed | Thinner materials, such as Kapton, PET, Melinex polyester film,3M VHB Tape are very commonly laser kiss cut. No metallics are done this way. Thickness ranges from 0.254mm up to 0.2032mm. | Larger range of materials processed and at greater thickness. Plastics, paper, foam, fabrics. |
| Notes/Concerns | May have limitations to on thicker materials. | Complex shapes may be problematic. |
Additional Considerations:
- Laser Kiss Cut: Ideal for intricate shapes, clean edges, and materials that can withstand laser cutting.
- Die Cut: Ideal for high-volume production, simple shapes, and materials that do not require precise edge quality.
- Hybrid Approach: In some cases, a combination of laser kiss cutting and die cutting can be used to achieve optimal results. Laser technology can be a great asset for projects needing R&D and development for the kiss cut precision part. Once evaluated, tested, and approved this can be moved to die cutting for high volume manufacturing.
In conclusion, laser kiss cutting has its place in the industry of precision components as well as the die cutting industry. Though dramatically different in their respective technologies, the results can be similar on certain projects. The application for the precision components using the chosen materials will likely direct which process is best. Cooperation between the customer and service providers can result in a production stream that takes advantage of both technologies.
Examples of How Kiss Cutting Works
Die cutting provides those sheets of stickers you can purchase with your favorite sports team logo and place them on your car bumper, luggage, or whatever suits you. This is an example of a die cut sheet. For laser kiss cutting the visual result is similar, but the applications are steered towards advanced technology uses. Die cutting too is used in many technical applications, but laser kiss cutting is almost always used in critical industries like medical device, automotive, aerospace, electronics and so on. The following list are some examples of applications where laser kiss cut parts are used:
Electronics and Semiconductor Industry
- Circuit Board Assembly: Kiss cut parts can be used to create flexible circuit boards, connectors, and other components.
- Insulation: Kapton, a heat-resistant polyimide film, is often used to insulate electrical components and wires.
- Protective films: PET and Mylar are used as protective films for displays, screens, and other electronic components.
Aerospace and Defense Industry
- Thermal Management: Kiss cut parts can be used to create heat sinks, insulators, and other thermal management components.
- Protective layers: These materials can be used to create protective layers for aircraft components, satellites, and other aerospace equipment.
- Antenna Components: Laser kiss cut parts are used in the construction of antennas and other communication components.
- Medical Devices: Kiss cut parts can be used to create components for medical devices, such as catheters, sensors, and patches.
- Diagnostic Tools: These materials are used in the production of diagnostic tools, such as X-ray films and MRI coils.
Automotive Industry
- Electrical Components: Kiss cut parts are used in the production of electrical components for vehicles, such as sensors, connectors, and wiring harnesses.
For these industries the application of the kiss cut part may be applied by hand or robotically for exact placement of the designated component. Kiss cut parts are provided in sheets but may be also supplied on rolls, depending on the laser processing systems used. Laser kiss cutting surplus can be stored in environmentally controlled areas with life spans per the manufacturer’s recommendations to the type of material used, including the adhesives. The examples listed indicate the need for greater precision that die cutting cannot provide and gives options for flexibility in developing new precision components as technological advances are made.