The food packaging bag manufacturer has problems with the operation of ink and glue

The food packaging bag manufacturer has problems with the operation of ink and glue

1、 The curing time in the curing room is not enough. The basic curing time of the high-temperature cooking bag is 48 hours, but sometimes it needs to be adjusted according to the size of the high-temperature cooking bag and the size of the ink surface. If the curing time is not enough, the high temperature resistance and hydrolysis resistance of the ink layer will be reduced.

2、 There is a problem with the curing agent ratio of cooking glue. The higher the ratio of curing agent is, the more standard the cooking bag is. More will lead to ink delamination, and less will affect the adhesion and hydrolysis resistance of the ink layer.

3、 Use expired ink or glue. The water activity of expired ink and glue is not good, which will cause the adhesion of the boiled bag to fail to meet the requirements.

3. Incompatibility between ink, glue and film

According to the adhesion theory, when the surface tension of the adhesive and the adhesive is equal and the polarity is the same, the interfacial tension is small and the adhesion strength is high. Therefore, the surface of the ink and glue solidified into film and the condition of the film surface may vary with the products of different color printing manufacturers. Because the groups on the surface can not be well attracted to form intermolecular force or chemical reaction to form chemical bonds, even if there is a certain effect to form adhesion at low temperature, but at high temperature, the weak connection of the surface groups may be damaged and delamination may occur.

4. Thin film problem

It is shown in the following two aspects: first, the film treatment degree cannot meet the requirements, or it is not treated at all. Operators often do not find this problem, so that the adhesion fastness is not high after printing, lamination and aging. This problem is only found after delamination after cooking. In production practice, I have found several such cases. The second is that some additives in the film speed up the dissociation to the surface at high temperature, which may cause the decrease of adhesion. Such as the opening agent, antistatic agent, and slippery agent added in the plastic film.