Teach you how to distinguish between good and bad tape

How to distinguish between good and bad colored tape?

For colored tape, it is used for marking and masking purposes, and generally beige and earthy yellow are more common. Many people think that colored tape is the color of the film, but in fact, the color is the color of the glue. Pinch the adhesive tightly and quickly pull it apart to remove one side of the glue, and you can see the purity and transparency of the original film. It is important to see the thickness of the glue. If there is no glue that is pulled apart or pulled apart in a spot, there are a large number of impurities in this glue, and the glue does not have cohesive force. The second reason is that there is too much moisture, which has already evaporated. At this point, the initial adhesion of this tape has decreased significantly, and the hand feel can distinguish it.

Apply yellow tape onto the object, and the thicker the adhesive with better masking properties, the better the quality. Compared to the appearance, adhesive tape has less glue on it, and the color of the entire roll of tape mixed with impurities is very dark. After opening, the tape has high transparency. The color of the entire roll of good tape is not much different from the color of the next layer after opening, because good tape has strong masking properties and there is no color overlap. Poor quality tape mixed with impurities needs to be coated onto BOPP film, and only the relatively backward direct gluing method can be used. Therefore, there are often large impurity particles that are not completely dissolved, resulting in knife jamming. Therefore, the tape often has lines (areas without glue) during use. Good adhesive tape is transferred by soft scraping, without any lines (the occurrence of ink leakage or insufficient printing on the printing tape is related to the printing machine).

Another way to distinguish is to look at the surface of the tape. When the tape is first divided into finished products, there are bubbles. After being left for a week, the bubbles will basically dissipate. The surface of the tape made of pure resin glue is smooth and free of any white spots. Adhesive tape mixed with impurities has many irregularly distributed white spots that cannot be dispersed by hand pressure, which is different from bubbles.

The adhesive for ordinary box sealing packaging tape is acrylic adhesive, also known as pressure-sensitive adhesive, mainly composed of resin. Tincal fat is a high molecular active substance, and temperature has a certain impact on molecular activity. The grease content of glue directly affects the use of adhesive tape. Many people believe that adhesive tape with a good hand feel is better than glue, but this is actually incorrect. There are two standards for the quality of adhesive tape in use, one is the initial adhesion force, and the other is the retention force, both of which are inversely proportional. Generally speaking, tapes with adhesive strength lower than 10 microns have less adhesive coverage, usually only about 20 microns, such as stationery tapes and regular promotional bundling tapes. The initial adhesive strength of normal sealing tape is between 15-20 microns, and the thickness of this tape adhesive is generally 22-28 microns. It is a thickness that meets the standard. But currently, most of the adhesive tapes on the market are mixed with impurities, so the thickness increases. In order to cover the impurities, the glue also contains color powder, so transparent tapes appear egg yellow and light green. These tapes are generally of poor quality.

In summary, everyone can basically judge the quality of adhesive tape from its appearance. Another important condition for distinguishing between good and bad adhesive tape is not to rely solely on the feel of viscosity, because adhesive tape with impurities has a very high initial adhesion when it has not evaporated. Therefore, it is necessary to use adhesive tape to stick objects and quickly pull them apart to see the retention force. After repeatedly sticking them a few times and then touching them with your hand, the adhesion will noticeably decrease. When formulating adhesive for tape mixed with impurities, gasoline and acid are usually used to dissolve it, so the odor is very strong. Regular large enterprises use toluene to dissolve it, and it has already been evaporated by the fan during the coating process.