UV laser prints white text or pattern on black plastic cover

Release time:2021/09/15

UV laser prints white text or pattern on black plastic cover


UV lasers are widely used in industrial marking, engraving and micro-machining fields due to their unique properties. One common application is marking on a variety of materials, including white text or graphics on black plastic. So, how does UV laser achieve this effect? This article will delve into the principles behind it.


1. Basic characteristics of UV lasers


UV lasers typically have an output with a wavelength in the range of 200-400nm, which has high photon energy. This allows it to produce unique physical and chemical effects when interacting with matter.


355nm uv laser mark white on black plastic charging socket



2. Marking principle


When the ultraviolet laser beam hits the black plastic surface, the following mechanisms will occur simultaneously or sequentially:


2.1 Photothermal effect:

The high energy of the laser causes the plastic to heat and cool rapidly, forming tiny expansions and contractions, resulting in changes in the material's structure.


2.2 Photolysis effect:

The high energy of UV laser can cause certain chemical bonds in plastics to break and form new chemical structures or products.


2.3 Color change:

The structural and chemical changes mentioned above may cause the color of the plastic to change. For black plastics, these changes usually appear as white or light-colored markings.


3. Advantages


3.1 Contactless Marking:

UV laser marking is a contactless process that causes no mechanical stress or damage to the material.


3.2 High resolution:

Very fine text and patterns can be achieved, suitable for high-precision marking needs.


3.3 Drying process:

No need to use any ink or chemicals, environmentally friendly, no additional post-processing required.


3.4 Long-lasting and durable:

Compared with traditional ink marking, laser marking is more durable and not easy to wear or fade.


4. Application areas


UV laser marking has applications in a variety of fields, including electronics, medical devices, food and beverage packaging, automotive parts, and more. Black plastic covers are common in cosmetic packaging, electronic equipment, etc. The white markings are not only beautiful but also provide clear information or brand identification.



UV laser printing of white text or patterns on black plastic covers is an efficient, precise and environmentally friendly technology. The principles behind it include photothermal and photolytic effects, which lead to structural and chemical changes in materials, thereby achieving color changes. With the further development of technology, we expect that UV laser marking will be widely used in more application fields.

RFH 5w UV laser is best for plastic marking

The parameters are as follows

Parameters uv lasesr S9 5W
  Index unit      
激光波长 (Laser wavelength) 354.7 nm  
平均输出功率(Average Output Power) >5 W @30kHz
脉冲宽度(Pulse Width) <15 ns @30kHz
脉冲重复频率 (Pulse Repetition Rate) 20-200 kHz  
激光输出模式 (Spatial Mode) TEMoo    
光束质量 (M2) <1.2    
光斑直径 (Beam Diameter) 0.8±0.1 mm Measured at window
光束发散角 (Beam Full Divergence Angle) <1.5 mrad  
光斑椭圆度 (Beam Circularity) >90 %  
脉冲稳定性 (Pulse-to-Pulse Stability) <2 % RMS/@30kHz
功率稳定率 (Average Power Stability) <5 % RMS/8hr
光束指向稳定率 (Beam-Pointing Drift) <25 μrad/℃  
偏振度 (Polarization Ratio) >100:1    
偏振方向 (Polarization Orientation) Horizontal    
工作温湿度 (Operating Temp. & RH) 10 to 30

储存温湿度 (Storage Temp. & RH) -20 to 65

配电需要 (Electricity Requirement) 功耗 (Power Consumption) 100-240
单相Single phase
保修期 (Warranty) 18 months