EN

More: 13710252340

Plastic laser welding machine_Laser die cutting machine_Automatic laser engraving [Laiser Laser]

热搜词: 塑料激光焊接 激光打标机 请输入您想要了解的设备关键词……

首页 > NEWS > Industry News

Why can't pom plastic be colored with laser?

Release time:2024-05-17 10:31:50

【summary】

POM plastic (polyoxymethylene) is a high-performance material widely used in the field of engineering plastics. It is favored for its excellent mechanical properties and chemical resistance. However, in some applications, especially in the field of identification and decoration, using laser technology to mark the color on the POM surface faces many challenges. This article will analyze from the perspective of the properties of POM materials why it is impossible to mark the POM surface with color using UV lasers and fiber lasers, and although CO2 lasers can etch the surface, they still cannot achieve color marking.

POM plastic (polyoxymethylene) is a high-performance material widely used in the field of engineering plastics, and is highly favored for its excellent mechanical properties and chemical resistance. However, in some applications, especially in the field of identification and decoration, using laser technology to mark the surface of POM faces many challenges. This article will analyze from the perspective of the properties of POM materials why it is impossible to mark the surface of POM with UV lasers and fiber lasers, and why carbon dioxide lasers can etch the surface but still cannot achieve color marking.

 

Why cant pom plastic be colored with laser?(图1)

POM material properties

 First, we need to understand the basic properties of POM materials. POM is a crystalline polymer with high density, high crystallinity, high melting point, good mechanical strength and hardness. Its molecular structure contains a large number of CO bonds, which makes it excellent in thermal stability, chemical stability and friction performance. However, these excellent properties also make POM show different reactions from other plastics during laser processing.

 

UV laser and POM

 UV laser usually works in the wavelength range of about 355 nanometers, with the characteristics of high energy and high precision. In theory, UV laser can be used for surface marking of many plastics, because its high energy can destroy the polymer molecular chain, thus causing color change. However, for POM material, UV laser is not ideal.

 

This is because POM has high crystallinity and good thermal stability. Under ultraviolet laser irradiation, the energy is mainly dispersed on the entire material surface, causing local temperature rise and molecular chain interruption, but it does not cause obvious color changes. The high crystallinity makes it difficult for POM to undergo significant chemical changes in low temperature environments, and although the energy of ultraviolet laser is high, it is not enough to cause a color reaction in the POM material in a short period of time. In addition, POM has a low absorption rate of ultraviolet light, which makes it impossible to effectively concentrate the laser energy in a local area to form a color change.

 

Fiber Laser and POM

 Fiber laser generally operates in the near-infrared wavelength range of 1064 nanometers, has high energy density and good beam quality, and is widely used in marking metals and some plastics. However, POM is also not sensitive to fiber lasers with a wavelength of 1064 nanometers.

 

The reason is that POM material also has low absorption of near-infrared wavelengths, and the laser energy cannot be effectively concentrated on the surface of the material, so it cannot generate enough heat to change the color of the material. The high crystallinity and density of POM make it difficult for it to undergo physical or chemical changes under the action of fiber lasers, and the surface still maintains its original characteristics without color change. In contrast, fiber lasers are more suitable for materials that absorb near-infrared light better, such as partially dyed plastics or metals.

 

CO2 Laser and POM

 CO2 laser operates in the far-infrared wavelength range of 10.6 microns. Its main feature is that it has a good absorption rate for most non-metallic materials and can effectively process and etch on the plastic surface. For POM material, CO2 laser can produce significant etching effect, but color marking is still not possible.

 

This is because although the CO2 laser can produce a high temperature effect on the surface of POM, causing the material to partially melt and vaporize, thus forming clear etching marks, this is mainly a physical change rather than a chemical change. The high temperature effect is not enough to cause the POM molecules to react with color. The laser can only remove the material or change its surface morphology without causing a change in color. The chemical structure and high crystallinity of POM prevent it from changing color at high temperatures like other plastics (such as PVC or acrylic).

 


In summary, POM material exhibits unique characteristics in the laser marking process due to its high crystallinity, good thermal stability and special chemical structure. UV laser and fiber laser cannot produce color on the POM surface due to insufficient energy absorption and material property limitations, while CO2 laser can etch the surface but still cannot cause color changes. This property limits the use of POM in certain applications that require color marking, but its excellent mechanical properties and chemical resistance still make it widely used in other fields.

 

In the future, perhaps by modifying POM materials or developing new laser technologies, these challenges can be overcome and color marking of POM surfaces can be achieved, opening up new possibilities for its application in the fields of identification and decoration.


Previous: Can PC and PMMA be welded with

Next:Effect of product flatness on