Adhesive composite packaging for dry composite packaging
DATE：2021/9/30 8:25:57 / READ： / SOURCE：This station
Adhesive composite packaging for dry composite packaging
Adhesives for dry composite packaging. The basic requirements for adhesives for composite packaging are many types of adhesives. As the adhesives used in composite packaging, especially food and pharmaceutical composite packaging, the following properties must be possessed.
1. Softness
The flexibility of composite packaging materials is very important, and now people call composite packaging materials based on plastic films as flexible packaging. In addition to the base material itself to be soft and foldable, the adhesive must also have this performance. If the composite material is hard and unfoldable, it loses the meaning of flexible packaging.
2. Heat resistance
After many foods are packaged with composite packaging materials, they are subjected to high temperature sterilization. For example, cooking food should undergo high-temperature steaming sterilization at 145°C for 2 minutes or 121°C for 40 minutes. This not only requires that various substrates can withstand the test of high temperature, but the adhesive used must also withstand the test of high temperature, otherwise, the original composite material will be peeled off in layers, and it is not a composite packaging material. , This must be carefully considered when selecting adhesives.
3. Cold resistance
There are many foods that need to be refrigerated or frozen at low temperature after being packaged, which requires the packaging material itself to be able to withstand low temperatures. If the adhesive becomes hard, brittle, delamination, peeling, and degumming at low temperatures, it won't work. Sometimes heat-resistant and cold-resistant packaging materials may be required at the same time. If you encounter this type of packaging, you must choose an adhesive that is both heat-resistant and cold-resistant.
4. Good adhesion
Since composite packaging materials are made of a variety of materials with different properties, they are bonded together with adhesives. Therefore, the adhesive must have good adhesion to various materials. If it can only stick to one of the substrates, but not the other substrate, it won't work. The substrates used in composite packaging materials include paper, fabric, aluminum foil, plastics, etc., and there are various types of plastic films, and their surface characteristics are also different. Faced with so many and complex materials, the adhesive must have the ability to bond two different materials at the same time.
5. Resistance to media
Food itself is a very complex substance, including water, oil, salt, wine, acid, spicy, spices, and even acetic acid, citric acid, lactic acid, sugar, sulfide, oxides, etc. Faced with such a complex composition, after packaging, it has to withstand the test of high and low temperature treatment and long-term storage to keep the packaging material perfect. In addition to the excellent resistance to media corrosion of the substrate itself, the stability of the adhesive is also very important. It must resist the erosion of various media, otherwise it will cause the composite to delaminate.
6. Good hygiene
It has no peculiar smell and smell, and the other is non-toxic. Since food and medicine are protected by packaging materials, and the things they are packaged are directly ingested by people, the food or medicine that is eaten almost every day, in order to be responsible for the health and safety of consumers, not only requires the base material to be tasteless and non-smooth. , Non-toxic, and the adhesives used are required to have the same properties. This is a matter of vital importance to human life, and all countries in the world pay great attention to and value it. In addition to formulating the Food Sanitation Law, my country has also formulated sanitary standards for packaging materials. The sanitary standard for composite packaging materials is CB9683-88.
The above 6 points are very important properties, and sufficient preparations must be made before dry compounding.
Author：admin