How to choose whitening agent for plastic film

Plastic film has the characteristics of light weight, soft, transparent and so on. The packaging material made of plastic film is beautiful and generous, and has a wide range of applications; Compared with other traditional packaging materials, plastic film can make up for the shortage of metal and paper packaging materials; Plastic film is a kind of packaging material for sustainable development because of its simple forming, low energy consumption, renewable and low price.

 

plastic film

 

Therefore, the growth rate of plastic packaging materials is far higher than other packaging materials, and has become a main force in the field of packaging.

 

Fluorescent brightener is a kind of additive commonly used in the production of plastic film. In the selection of Brightener for plastic film, attention should be paid to the dispersibility, heat resistance and migration resistance of brightener.

 

1. Dispersion most of our common plastic film appearance is transparent, if the choice of fluorescent whitening agent dispersion is not good, it is very easy to cause the product to produce particles, directly affect the appearance of the product.

 

In addition, if the dispersed particles remain in the plastic film all the time, it will have an adverse effect on the sealing performance of the film packaging bag products.

 

2. Heat resistant extrusion film blowing is a high-temperature processing technology. It is based on different resin and film blowing requirements. The general operating temperature is 180-240 ℃. The fluorescent whitening agent for plastic film must be able to operate for tens of seconds to several minutes at this temperature. Therefore, the heat resistance of fluorescent whitening agent is one of the important characteristics that must be possessed.

 

3. The main application of migration resistant plastic film is as packaging materials. If the fluorescent whitening agent used migrates, it is easy to cause the transparent plastic film to show the appearance color of whitening agent, resulting in the appearance yellow of the film product, which is not worth the loss.