The Principle of Laser Marking Printing Black and White

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lasercuting
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The Principle of Laser Marking Printing Black and White

Post by lasercuting »

Laser marking has been widely used in various industries of plastic marking. It uses the high energy of laser to make the plastic surface carbonized or some components on the surface decompose to cause the plastic foaming, so as to get a mark with a large color difference from the product body base color. Compared with traditional printing marks such as screen printing, transfer printing, embossing, ink printing and other surface printing methods may cause signs of faintness, wear, and loss due to prolonged use. At the same time, the environmental friendliness is poor and the cost is high. So, the laser marking is undoubtedly more advantageous.
Laser marking is a very flexible way to clearly and quickly mark difficult-to-erase icons on plastic. The laser marking machines can achieve high repeatability and reliability when processing products. More importantly, laser marking can be achieved offline (or independent) integration into the assembly line, more convenient and effective with the follow-up processes, so as to achieve the effect of reducing costs and improving quality.
Plastic dark and light-colored marking lasers are based on the reorganization or color change of the surface of the material during plastic marking and can be divided into four different types of markings: blistering, engraving sags, engraving sags and changes in color ,Color changes. Of course there are also many plastic samples that without adding adjuvants do not produce any changes after processing.
How to achieve color marking? There are several determinants:
Laser wavelength characteristics of laser marking machine. For example, different laser wavelengths will react with different colors to different materials. CO2 lasers can print reddish letters on PVC pipes, while 1064NM lasers on fiber optics or semiconductors can print black letters.
Laser spot characteristics. Generally speaking, the closer the laser spot is to the base mode (TEM00), the color will be clearer and brighter.
Quality of optical focusing lenses used by laser marking machines. The multiplier of the beam expander and the quality of the focusing lens of the field lens are the same as those of the second factor. The frequency of laser marking machines varies, and the effect of marking will be different. Some laser marking machines cannot be tuned to very high frequencies, and some can be tuned to very high frequencies, so that the color of the markings will also be different.
Different adjustment of speed and power in the laser marking process will distinguish the colors. In the process of laser marking, there is also a relationship between the positive and the defocused marking. For example, if you want to have a black effect on high carbon steel or stainless steel, except for using a semiconductor laser tag and a fiber-optic laser tag, you're going to have to debug it for slower speeds, lower energy, higher frequencies, and you have to have a certain amount of focus, this will take to get twice the result with half the effort effect.
The impurities of processed goods are different. For example, imported acrylic and domestic acrylic have different effects and colours, the latter of which has a lot of useless impurities.
The ratio of material atoms in the materials processed. For example, if the content of carbon in high-carbon steel is high, of course it is easier to fight black and the effect of black is better.
The temperature of the object being processed. When the object is covered with a film and then marked, the different colors can be printed. For example, when marking on ceramics, there are different color effects after adding colored paper.
Many special materials, such as metal anodic alumina, make black marks. Soft base materials, such as silica gel, need special equipment and some setting skills to produce excellent results.
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