How to judge whether the thermal coating of BOPP thermal synthetic paper is uniform?

To determine whether the thermal coating of BOPP thermal synthetic paper is uniform, you can start from the following aspects:

First, appearance inspection

1. Color observation

Good quality BOPP thermal synthetic paper, the thermal coating should present a uniform color, such as a slight green or black green. If the paper color is too white and highly reflective, it may indicate that too much phosphor has been added, which usually means that the heat-sensitive coating formulation is not reasonable or the coating is not uniform.

2. Finish and uniformity

Observe the surface finish of the paper, a good heat-sensitive synthetic paper surface should be smooth and smooth, no obvious uneven or coating peeling phenomenon. If the surface finish of the paper is not high or looks uneven, it may indicate that the thermal sensitive coating is not evenly distributed.

Second, fire test

Fire roasting method: Use a lighter to gently heat the back of BOPP thermal synthetic paper. Observe the color change of the paper after heating. If the color of the paper is brown after heating, and the black part has small stripes or uneven color blocks, this may indicate that the thermal sensitive formula is not very reasonable or the coating is not uniform, resulting in a shorter storage time. On the contrary, the better quality paper should show a black green (with a little green) after heating, and the color block is evenly distributed, and the color gradually fades from the heating center to the four sides.

Third, print effect evaluation

Print test: Print test on BOPP thermal synthetic paper to observe whether the printed pattern and text are clear, whether the edge is neat, and whether the color is uniform. If the printing result is poor, such as blurred handwriting, different shades of color or rough edges, it may indicate uneven thermal coating or other problems.

Fourth, professional testing equipment

Use professional equipment: For more accurate inspection, professional inspection instruments can be used to measure the thermal coating uniformity of BOPP thermal synthetic paper. These instruments can provide more accurate data and results.

Fifth, other precautions

When performing the above tests, pay attention to safe operations to avoid accidents such as fire or scalding. At the same time, because different brands and models of BOPP thermal synthetic paper may have differences in the formulation and production process, a comprehensive evaluation should be carried out in combination with the characteristics and requirements of specific products when judging whether the thermal sensitive coating is uniform.

In summary, through the appearance inspection, fire test, printing effect evaluation and the use of professional testing instruments, we can more accurately judge whether the thermal coating of BOPP thermal synthetic paper is uniform.