Colored tapes are mainly used for marking and masking purposes, with beige and khaki being the most common colors. Many people think that the color of the tape comes from the film itself, but in fact the color comes from the adhesive. To test it, stick two pieces of tape together (adhesive sides facing each other), squeeze them tightly, then pull them apart quickly. This will peel the adhesive off one side, allowing you to see the purity and transparency of the original film. The key point is to observe the thickness of the adhesive. If no adhesive is pulled off, or only small spots of adhesive come off, it indicates that the adhesive contains a lot of impurities and lacks internal cohesion. Another possibility is that the adhesive contains too much water which has already evaporated, significantly reducing the tape's initial tack – something you can feel by touch.

Apply the yellow tape onto an object; the better the masking effect, the thicker the adhesive layer, and the better the quality.

Another important factor in distinguishing good tape from bad tape is not to rely solely on feel for tackiness. Because tapes with impurities can have very high initial tack before the solvents evaporate. Therefore, you should stick the tape onto an object, pull it off quickly to test holding power, and repeat this several times. Then touch the adhesive – you will clearly feel a drop in tackiness. In tapes containing impurities, the adhesive formulation often uses gasoline and acid as solvents, resulting in a very strong odor. Reputable manufacturers use toluene as a solvent, which is evaporated off by fans during the coating process.

After all this, you might ask: what is the actual difference in use between good and bad tape? In fact, the purpose of using tape is not just to stick, but to stick firmly and stay stuck. Most tapes that contain impurities will come loose (pop open) after a period of time (20 minutes to 1 hour) during packaging operations, and they cannot be re-stuck. This is especially obvious in low-temperature environments or dry, windy conditions. Additionally, low-quality tape is easy to break and has low strength – this is mainly related to the quality of the film.