Friction resistance test method and precautions of ink

(1) Purpose and definition.

The rubbing resistance of the ink film is extremely important for the printing of packaging materials. Because packaged goods often have to go through many links such as storage, transportation and sales, each link may cause the surface of the package to be rubbed, and the ink with poor friction resistance will therefore damage the ink imprint on the package surface.

Auxiliary waxes that increase the smoothness of printed matter, it is a material that can increase the smoothness of oil plastics and thus improve their friction resistance. The amount currently used in ink is about 2-3%.

(2) Appliances and materials.

1. Appliances:

(1) Friction resistance Tester.

(2) Printability Tester.

2. Material: coated paper.

(3) Method.

The oil to be tested was printed on coated paper with a printability Tester. Let it dry at room temperature.

Put the printed sample and white paper (coated paper ) on the friction Tester, and rub it back and forth for a certain number of times (such as 20 times, 50 times, etc.) under a certain pressure ( such as one kilogram).

Take it off, observe the rub marks on the print sample, and grade according to the severity of the rub marks on the print sample.

(4) Matters needing attention.

1. Writing paper can also be used as the white paper used to measure the friction resistance, but it needs to be stable and the quality of the paper should be uniform.

2. It is also difficult to evaluate the level of friction resistance. Generally speaking, it is basically enough to rub 20 times without much scratch.

The "Color Fastness Fading Sample Card" can be used to evaluate the grade. When evaluating, the part with the largest friction damage can be juxtaposed with the part without friction. When the color difference between the rubbed part of the ink imprint and the part without rubbing is equivalent to the difference of a certain level in the "Color Fastness Fading Sample Card", it is evaluated according to this level. Level 5 is better, and level 1 is the worst; if it is between two levels, it can be rated as an intermediate level, for example, written as level 2-3, which means that it is better than level 2, and level 3 is worse.