The plastic, metal, and paper layers exhibit different absorption and reflection properties in different wavelength ranges of CO2 lasers. PET/Aluminum/PE, which is a typical composite material for food packaging, such as coffee packaging bags. The material's selective absorption of the CO2 laser at 10.6 wavelengths allows for complete vaporization of the PET layer in very fine localities without affecting the other layers, and the reflection effect of the foil layer facilitates a more efficient use of the laser to achieve the effect of layer cutting. As a laser layer cutting technology for easy tear technology, it is used in a wide variety of food packaging bags and daily necessities packaging bags. In these applications, laser technology offers the following advantages over mechanical methods such as conventional rotary tools: 1. The special selectivity of the laser for different film materials makes it possible to cut a certain film layer without affecting other layers. 2. Different from machining, there is no contact and wear during laser processing, which ensures the reliability of the process in the high-speed processing process. 3. Machining needs to change the film and tools frequently, and it cannot control the direction of the tearing line after the customer tears, and often cannot tear along the easy-to-tear line of the product design. The laser technology layer cuts the easy-to-tear line, which not only does not destroy the packaging function, but also allows the tearing line to be torn along the easy-to-tear line, and the nicking is basically invisible, making the packaging design more flexible. Laser scribing technology is a more advanced and flexible technology that concentrates laser energy on the thin film layer that needs to be scribed without damaging the entire film. Because composite films such as PET, PP or PE all have different wavelengths of absorbing and emitting CO2 lasers, when one layer of film absorbs the laser energy and disappears, the other layers remain 100% intact and are not affected in any way. On the other hand, the aluminium foil layer or other thin film coated with a metal layer acts as a barrier to the laser to other material layers. Therefore, the characteristics of these materials allow laser technology to accurately locate and scribe on packaging materials. At the same time, the tear-off line is clearly visible through the human eye, so tearing the packaging is a breeze for consumers. It is worth noting that laser scribing technology is a non-contact and wear-free process for food packaging, so it also ensures that the goods in the package will not be damaged due to the packaging process, ensuring the stability and reliability of the goods.