Injection molding machine die-cutting products are more and more widely used in our daily life, and PE protective film is one of them.
PE protective film is made of polyethylene plastic (PE) as the base material, cross linked polypropylene (PP) acid resin as the adhesive, and a variety of special auxiliary additives. Glue has no color, as clear as water, no mottled, soft. It can quickly achieve the viscosity we want, and has a wide range of protection for various materials. Different types, viscosity and specifications of protective films can be selected according to the surface of different materials.
Compared with the previous years, the quality of PE protective film products in China has been greatly improved, but there are still many details that need to be improved. Here are some common quality problems of PE protective film from several aspects, and how to solve them for PE protective film manufacturers?
1、 It is difficult to peel the PE protective film of injection molding machine. There are two possibilities:
1. The pressure-sensitive adhesive used for PE protective film is not a special pressure-sensitive adhesive. Although the effect of PE protective film is very good when it is adhered, it is difficult to peel it off. This is also a common problem of some illegal protective film manufacturers.
2. The material used for PE protective film mother belt is too soft to bear the pulling force of peeling, and it breaks when peeling.
To solve this problem, we must start from the root, change the pressure-sensitive adhesive or change the material of the protective film.
2、 PE protective film degumming of injection molding machine
When the user tear the PE protective film off the profile surface after the profile is installed, the adhesive of PE protective film does not fall off with the protective film, but remains on the profile product. In this case, the pressure glue used for PE protective film product may not meet the requirements, that is, it is too sticky. In the process of peeling off, the external tension is greater than the internal force, so the protective film remains on the profile.
3、 The PE protective film of injection molding machine is not firmly pasted with the protected product
In the process of transportation and use, the phenomenon of falling off occurs. The reason for this problem is the opposite of the previous one. The biggest possibility is that the viscosity of the sensitive adhesive used in the production of PE protective film products is not enough. Another possibility is that the pressure of the die press used by the user in the process of pasting the die is not enough, or the surface of the profile is not cleaned up, and there is dust or paint on it, which affects the pasting effect of the sensitive adhesive.
4、 The PE protective film of injection molding machine is warped at both ends after being used for a period of time.
The reason for this phenomenon is that the PE protective film is due to the large degree of stretching during the pasting process of the protected profile. After being pasted, it will encounter a high temperature environment, which will lead to the phenomenon of shrinkage.
In addition to the above common quality problems, the following also introduces how PE protective film manufacturers solve the matters needing attention in die cutting process:
1. Mirror knife shall be used for die-cutting of protective film with tolerance of + / -0.1
2. The environment for die-cutting protective film must be invited to be produced in the standard 100 class 1000 class dust-free room, with the ambient temperature of 20-25 ℃ and the humidity of 80% - 85%.
3. The application hardness of die-cutting cushion foam is 38 ° - 45 ° and its density is dense, and its rebound is good. Foam thickness is 0.2mm higher than the knife
4. Single seat flat knife machine + compound machine + labeling machine.
5. A layer of 5g PE protective film is added on one side of the PE protective film as the protective effect and supporting base.