Since the outbreak of the epidemic, masks have become a necessity of life at this stage. However, the huge demand gap has caused some illegal traders to take advantage of it, and a large number of low-quality masks have flowed into the market. The terms related to fake mask fraud have been frequently searched. The fake mask not only has no protective effect, but also has the risk of being polluted due to the production environment sanitation not meeting the standard, which is extremely harmful to personal health. The most direct way to identify genuine and fake masks is to check the laser anti-counterfeiting marks. The mask laser marking machine solves this problem well.
For the boxed 3M N95 / kn95 series masks, they can be identified by the anti-counterfeiting label on the mask packaging box. The label of the real mask will change color from different angles, while the label of the fake mask will not change color. For 3M N95 / kn95 series masks in bulk, the authenticity can be identified by observing the font on the mask. The words of the real 3M mask are printed by the mask laser marking machine, and the font has diagonal lines, while the fake is printed by ink, with dots (uneven marks of ink).
In fact, the anti-counterfeiting technology of mask laser marking machine can not only be used for the identification of mask authenticity, but also plays a great role in the packaging anti-counterfeiting and tracing of food, medicine, tobacco, beauty, electronic products and other fields. It can be said that laser marking anti-counterfeiting has been integrated into all aspects of our life. So why can laser marking play such a huge role in the packaging anti-counterfeiting market? What advantages does it have over traditional methods?
Why is laser: the characteristics and application advantages of laser marking anti-counterfeiting:
The basic principle of laser marking is to use the laser beam with high energy density to act on the surface of the material, make the surface material vaporize or change color instantly by focusing, and control the path of the laser on the surface of the material to form the required permanent graphic marks. Since laser marking can print various characters, symbols and patterns, and the size of characters can range from millimeter to micrometer, which has special significance for product anti-counterfeiting, it is widely used in the anti-counterfeiting market.
Before the large-scale application of laser marking, the marks on the packaging were usually printed with ink. The marks printed by this traditional method are easy to fall off and blur over time, easy to be tampered with, and unable to perform high-precision operations. Although it has advantages in equipment cost, the continuous cost of consumables (ink) is high and will cause certain pollution to the environment.
Take the most common food packaging as an example. Because the marks printed by traditional methods are easy to erase and fall off, some lawless elements have printed some expired or even fake and shoddy products with brand marks, or modified the production date, so that these substandard products can circulate in the market. Such phenomena are common in the fields of grain and oil, beverages, snacks and sauces. In addition, for some paper food packaging, the harmful substances of the ink may also penetrate the packaging and contaminate the food, posing a threat to the health of consumers.
Marking of beverage bottle caps and food packaging:
The emergence of laser technology has solved a series of problems brought by traditional ink printing. For food packaging, the use of laser marking has the advantages of non-toxic, non pollution, high efficiency, high clarity, beautiful patterns, and never falling off. In addition, laser marking can also be combined with computer technology. By linking the database system, we can track and query the detailed information of food delivery and circulation in time to ensure that we can eat safely.
And the medical industry is inseparable from the escort of laser marking. Because medical products are in direct contact with the human body, which is related to the life and health of the people, the treatment and anti-counterfeiting of medical products have become the most important thing to protect the health and safety of consumers.
Marking of drugs and metal surfaces:
In addition to the characteristics mentioned above, there are some special requirements for the marking of medical devices and drugs. For example, for common pills and soft capsules, if lithography is used, pressure will be generated on the products. However, non-contact laser marking will not deform the capsules, and even smaller information can be marked on the small pills. On the medical instruments represented by stainless steel surgical and dental equipment, the laser can mark on the absolutely smooth surface, which can prevent bacteria from adhering to the surface, and the marked surface will not damage the corrosion-resistant chemical passivation treatment, so that the anti-corrosion coating can still exist even after several years of use and countless times of cleaning and disinfection. Another example is the 3M mask mentioned at the beginning. Whether there is a laser mark is an important sign to distinguish between the genuine and the fake.
Laser marking is also different: unique advantages of UV laser in food and medical applications
As we all know, there are many types of lasers, and the applicable materials are also different. For example, fiber laser is applicable to all kinds of metal materials, CO2 laser is applicable to most polymer materials, and UV laser is applicable to more precise and demanding application scenarios.
In fact, CO2 and fiber lasers have already developed marking applications. The light emitted by these lasers is in the infrared band. The essence of the marking process is to heat the material to bleaching, carbonization or ablation through thermal interaction to produce color contrast. However, this heating will change the chemical structure of the material in the heat affected zone (HAZ), causing carbonization or making the surface not smooth. For the plastics commonly used in food packaging, because of its low absorption rate of infrared light, the heat generated by infrared laser will damage the surface of some packaging materials, so it cannot be used in the food packaging industry on a large scale.
Under this background, the advantages of ultraviolet laser can be seen. Most materials absorb more ultraviolet light than infrared light, and the photon energy of ultraviolet laser is higher. When the UV laser acts on polymer such as pi, the chemical bond of the material can be directly broken, and the material fragments can be discharged in the form of small particles or gas, so as to achieve the purpose of stripping and removing the material. Since most of the energy is used to break the chemical bond, very little energy is converted into thermal energy, thus basically eliminating the changes in the heat affected zone (HAZ) and surrounding materials. For most white plastics (pigment is TiO2), TiO2 will strongly absorb ultraviolet rays and change the crystal structure. This change makes the substance in the corresponding area appear dark, thus producing smooth, clear and legible marks inside the material.
2、 Characteristics of UV laser
Full water-cooled constant temperature design, high-precision chiller, which can work stably for a long time within 35 ° of room temperature;
Built in collimation and beam expansion external optical path, convenient for customer integration;
Innovative laser frequency doubling design, good laser output stability, small fluctuation (< 2%) and good beam quality (M2 < 1.3);
Modular control system, easy to use, easy to maintain, low cost in later use;
Excellent product stability design can ensure long-term stable operation of the laser in harsh environment;
The optical components are accessories of international large manufacturers with guaranteed quality.
1. Introduction to overall performance
The UV laser marking machine is composed of software control system, computer control system, optical system and workbench.
① Control system: the control system controls the operation of the whole equipment, including power supply and control of optical system components and cooling system, and control and indication of alarm system.
② Computer control system: the computer control system includes a computer and a digital galvanometer card. It drives the optical system components to act according to the parameters set by the marking control software, and emits pulse laser, so as to accurately etch the content to be marked on the surface of the processed object. The control system has a full Chinese interface and can be compatible with files output by various software such as AutoCAD, CorelDRAW, Photoshop, etc. it can mark bar codes, two-dimensional codes, graphic characters, etc. it supports PLT, PCX, DXF, BMP, AI and other file formats. It can directly use SHX and TTF font library to automatically code and print serial numbers, batch numbers, dates, etc.
③ Optical system: the optical system includes laser, galvanometer scanning system, focusing lens and other components. The laser beam output by the laser is irradiated on a group of mirrors of the galvanometer scanning system. The two deflectable mirrors are respectively clamped on two precision galvanometer motors (high-speed galvanometer). When the galvanometer is driven by the computer voltage signal and acts, the two mirrors are driven to rotate, so as to realize the deflection of the laser beam. The deflected laser beam is irradiated on different positions on the workpiece, A predetermined figure or character is formed on the surface of the object. The key components of the optical system are imported high-quality brand products with high precision, fast speed and stable performance, which can meet the requirements of long-term continuous work.
④ Cooling system: the cooling system of the laser marking machine adopts the high-precision water cooling method, and the cooling system ensures the long-term and stable operation of the optical system.
⑤ Machine features: compact appearance and small volume.
3、 Working environment requirements
The ambient temperature is required to be between 10-35 ℃, and air conditioning is required for others.
Humidity requirement is 40% - 80%. No condensation, dehumidifier should be installed.
Power supply grid requirements: 220V; 50Hz
Fluctuation of power supply grid: ± 5%, and the ground wire of power grid meets international requirements. In areas with voltage amplitude of more than 5%, electronic automatic voltage stabilization and current stabilization devices shall be installed.
There shall be no strong electromagnetic signal interference near the installed equipment. Avoid radio transmitting stations (or relay stations) around the installation site.
Foundation amplitude: less than 50um; Vibration acceleration: less than 0.05g. Avoid a large number of stamping and other machine tools nearby. The equipment space shall be smoke-free and dust-free, so as to avoid working environment with serious dust such as metal polishing and grinding.
Air pressure: 86-106kpa.
Some environments should be equipped with anti-static floor and strengthened shielding.
4、 Industry application
Laser marking of mask, logo marking of high-end electronic products, marking of food, PVC pipes and medical packaging materials (HDPE, Po, PP, etc.), micropore marking, pore diameter D ≤ 10 μ m. Marking and dicing of flexible PCB board.