How to improve the printing effect of BOPP color synthetic paper by controlling the printing pressure?

Controlling the printing pressure to improve the printing effect of BOPP color synthetic paper is an important process step. Here are some specific control methods and suggestions:

1、 The role of printing pressure

Realize complete contact: Printing pressure can deform the rough and micro pores on the surface of paper, rubber blanket, and printing plate under pressure, achieving reliable and complete contact, overcoming surface roughness and unevenness, and thus achieving effective ink transfer.

Overcoming the attraction of ink molecules: Printing pressure helps to enhance the adsorption force of ink, making it exceed the attraction between ink molecules. In the case of close contact distance, ink can break and be transferred from the middle.

Pressure penetration effect: Printing pressure can promote the penetration of ink onto paper by the connecting material after printing. The penetration of ink on paper includes two physical phenomena: pressure penetration and free penetration.

2、 Methods for controlling printing pressure

Adjust the thickness of the pad:

Reduce the thickness of the padding under the blanket cylinder: By reducing the padding under the blanket cylinder, printing pressure can be increased, allowing ink to be more effectively transferred to the substrate (BOPP color synthetic paper).

Increase the thickness of the liner under the plate cylinder: If you need to reduce the printing pressure, you can achieve this by increasing the thickness of the liner under the plate cylinder.

Adjusting center distance: For slight differences in printing pressure, fine adjustments can be made by adjusting the center distance of the printing machine.

3、 Precautions

Adjust according to paper characteristics: BOPP color synthetic paper has a certain thickness and hardness, so the printing pressure needs to be adjusted according to its characteristics. Excessive pressure may cause paper deformation or excessive ink penetration, while insufficient pressure may result in incomplete ink transfer, affecting the printing effect.

Maintain pressure uniformity: When adjusting the printing pressure, ensure that the pressure in the entire printing area is uniform and consistent to avoid local printing defects.

Regular maintenance and inspection: Regularly maintain and inspect various components of the printing machine to ensure the stability and uniformity of pressure during the printing process. This helps maintain high-quality output of printed materials.

4、 Optimization suggestions in practice

Conduct printing tests: Before actual printing, some printing tests can be conducted to observe the effect of different printing pressures on the printing effect. By comparing printed samples under different pressures, the optimal printing pressure setting can be found.

Communicate with ink suppliers: The fluidity and adhesion of ink have a significant impact on the printing effect. Therefore, when choosing ink, it is advisable to communicate with the ink supplier, understand the characteristics of the ink, and adjust the printing pressure according to their recommendations.

Consider environmental factors: The humidity and temperature in the printing workshop may also affect the printing effect. Therefore, when controlling printing pressure, it is also necessary to consider these environmental factors to ensure the stability of printing quality.

In summary, by controlling the printing pressure reasonably, the printing effect of BOPP color synthetic paper can be significantly improved. In practical operation, it is necessary to comprehensively consider and adjust various factors such as paper characteristics, ink properties, and environmental factors.