The hazards and elimination methods of static electricity in thermal transfer films

The hazards and elimination methods of static electricity in thermal transfer films

1 What is static electricity in thermal transfer films
The static electricity in thermal transfer films is generated by the friction between the films during the printing process of thermal transfer films due to the rotation adjusted on the printing machine. After the production is completed, these charges will remain in the packaged thermal transfer films. So what harm will these static electricity cause to the normally printed film products? Is there any way to eliminate them?

2 Hazards of static electricity in thermal transfer films
a. Affecting the printing quality of products

First, the surface of the substrate is charged, such as polyethylene, polypropylene, PET, etc. They will absorb a large amount of dust and impurities in the air, thereby affecting the transfer of ink, reducing the ink transfer rate, and appearing "flower spots", needle swelling or small white spots on the printed products, or causing slippage and uneven winding due to mutual repulsion. The discharge phenomenon of static electricity in thermal transfer films will also damage the surface coating of the material and affect the quality of the product. Secondly, the ink is charged, which will cause "static ink spots" to appear on the printed products.

b. Impact on production safety

In severe cases, charged substrates may even cause air discharge due to ultra-high potential, causing electric shock or fire.

3 Methods for eliminating static electricity in thermal transfer films

A. Physical elimination method

The physical elimination method is a method that uses the inherent characteristics of static electricity to eliminate static electricity without changing the function of the material. For example, the "grounding" elimination method is to install an antistatic brush in the process.

B. Chemical elimination method

The chemical elimination of static electricity in thermal transfer films is the antistatic agent treatment technology, which is mainly a method of modifying the electrical properties of resins or substrates by adding (filling) technology or coating technology with antistatic agents (surfactants). It is a more thorough and complete antistatic technology.

C. Additive treatment technology

This technology (i.e. masterbatch technology) is to mix the additive antistatic agent with a thermoplastic resin at a certain concentration (several percent to tens of percent), add a variety of additives, and obtain antistatic masterbatch through melting, mixing, and granulation.

D. Coating treatment technology

Coating antistatic agent treatment technology is to make ionic surfactants into antistatic coatings and apply them on the surface of plastic films to prevent charge accumulation. The selection of coating antistatic agents should be determined according to the work function of the coated substrate.