How to solve the color difference problem in the printing of BOPP synthetic paper?

To solve the color difference problem in BOPP synthetic paper printing, it is necessary to start from many aspects, including raw material control, printing process optimization, equipment maintenance and color management. Here are some specific solutions:

First, raw material control

1. Paper selection:

Ensure that the same batch of BOPP synthetic paper with the same whiteness, smoothness and ink absorption is used to avoid color differences between different batches of paper.

Check whether the paper itself has obvious color deviation, and avoid using paper with color difference for printing.

2. Ink Management:

Use the same manufacturer, the same model, the same batch of ink to ensure the consistency and stability of ink color.

Avoid mixing ink with a large proportion to avoid the phenomenon of ink stratification.

Adjust the transparency or hiding power of the ink as needed to ensure that the printing color meets the standard.

Second, printing process optimization

1. Plate making specification:

Ensure that the intensity and spectrum of the light source in the plate making process match the plate sensitive characteristics, and the exposure time and developer PH value and other parameters are properly controlled to avoid the color difference caused by too deep or too shallow plate dot.

2. Printing pressure adjustment:

Keep the printing pressure uniform and constant to avoid uneven ink layer thickness due to insufficient or uneven pressure.

Do a good job of "three flat" (flat plate surface, flat rubber cloth, flat substrate and envelope surface) to ensure that a thin ink layer through a balanced printing pressure action to obtain a more uniform ink color on the print.

3. Lubricant control:

The amount of moistening liquid directly affects the color of the ink layer, and it is necessary to strictly control the amount to avoid excessive emulsification of ink and light color.

4. Color Management:

Use color management systems such as ICC profiles for color conversion and calibration to ensure color consistency across equipment and processes.

Third, equipment maintenance

1. Regular cleaning and calibration:

Regularly clean and calibrate printing equipment, including ink rollers, water rollers, rollers and other components, to ensure that the surface is smooth and free of impurities, to avoid color differences caused by equipment pollution.

2. Check the operating status of the equipment:

Check equipment calibration and setup before printing to ensure proper operation. In case of abnormal adjustment or maintenance.

Fourth, color detection and adjustment

1. Use a color difference meter to detect:

In the printing process, the color difference meter and other instruments are used to detect the printed matter regularly, and the color difference problem is found and corrected in time.

The color of the sample is compared with the standard color plate, and the printing parameters are adjusted according to the analysis results until the color meets the requirements.

2. Create a color database:

Establish a standard color database to build a database of each color through a data mode, which is easy to quickly find and match colors to reduce the appearance of color differences.

Fifth, environmental control

1. Light source control:

When observing colors, standard light sources (such as D65 light sources) are used for color observation and color comparison to avoid color differences caused by inconsistent light source characteristics.

2. Temperature and humidity control:

Control the temperature and humidity of the printing workshop within the appropriate range to avoid changes in ink solubility caused by temperature and humidity changes and then affect the printing effect.

In summary, through strict control of raw materials, optimization of printing process, regular maintenance of equipment, strengthening color detection and adjustment and control of environmental factors and other measures can effectively solve the color difference problem in BOPP synthetic paper printing to improve printing quality and customer satisfaction.