The influence of substrate surface treatment on printing quality and analysis of activation treatment technology

1. The importance of substrate surface cleaning
Before the printing operation begins, the state of the surface of the substrate (such as paper, plastic film, metal sheet, etc.) is directly related to the quality of the printing effect. A clean surface free of oil, dust and other impurities is the basis for high-quality printing. Contaminants, whether tiny particles, grease or chemical residues, can become "stumbling blocks" in the printing process. They not only hinder the effective combination between the over printed foil or ink and the substrate, but also may cause spots, shedding or uneven color of the printed pattern, seriously affecting the overall visual effect and durability of the product.

Contaminants such as oil and dust will form an isolation layer on the surface of the substrate, which weakens the penetration and adhesion of the ink or foil, making the bond between the printed layer and the substrate fragile. In addition, some contaminants may also contain components that can react adversely with the ink, further affecting the printing quality and drying speed. Therefore, thoroughly cleaning the substrate surface and removing all potential contaminants is the first step to ensure successful printing.

2. Surface activation treatment technology
In order to overcome the challenges brought by insufficient surface cleanliness of the substrate and further enhance the bonding strength between the printed foil or ink and the substrate, surface activation treatment technology came into being. These technologies change the microstructure and chemical properties of the substrate surface by physical or chemical means, making it more conducive to the adhesion of printed materials.

Corona treatment: Corona treatment is a commonly used physical activation method. It uses a high-frequency and high-voltage electric field to excite gas molecules in the air to generate plasma. These plasmas hit the surface of the substrate, breaking its surface molecular chains and forming more polar groups, increasing the surface roughness and wettability, thereby improving the adhesion of ink or foil. Corona treatment is widely used in the pretreatment of materials such as plastic films and paper.
Plasma treatment: Plasma treatment technology is more sophisticated and controllable than corona treatment. It can achieve deep modification of the material surface at a lower temperature. The high-energy particles in the plasma can directly act on the surface of the substrate, remove weak boundary layers, introduce polar functional groups, and even change the chemical composition of the surface, greatly enhancing the interaction between the substrate and the printed material. This method is particularly suitable for precision printed products with special requirements for surface properties.
3. Implementation strategies and precautions
When implementing surface activation treatment, it is necessary to comprehensively consider and select appropriate technical parameters based on factors such as substrate type, printing requirements, and cost budget. At the same time, pay attention to the control of treatment time. If it is too short, it may not achieve the ideal activation effect, and if it is too long, it may damage the substrate and affect its physical properties. In addition, the treated substrate should be printed as soon as possible to avoid secondary contamination and maintain the timeliness of the activation effect.