Plastic packaging bag is a kind of packaging bag that uses plastic as raw material to produce various items in daily life. It is widely used in daily life and industrial production, but the convenience at this time has brought serious pollution. Most commonly used plastic packaging bags are made of polyethylene film, which is non-toxic and can be used to hold food. Plastic packaging bags can completely isolate the entry of air and light, are safe and sanitary, are degradable and recyclable, have strong flexibility, strong tear resistance, and have good printing effects. They can achieve multi-color and multi-graphic printing to achieve exquisite, compact effects, and are easy to carry and use. Plastic packaging bags have many packaging advantages: plastic packaging bags are light in weight, low in production costs, strong in chemical stability, will not deform at room temperature, will not produce peculiar smell, have good air tightness, can effectively avoid light and moisture, and achieve fresh-keeping content. Extend the shelf life of products. It plays an important role in food circulation and sales.

The following describes the manufacturing requirements of plastic packaging bags:

1. The appearance of the plastic packaging bag must not have bubbles, perforations, water lines, poor plasticization, etc. These problems are inconvenient to use. The deviation of specification width, length and thickness should be within the specified deviation range.

2. In the process of manufacturing plastic packaging bags, the physical and mechanical properties include tensile strength and elongation at break, which reflect the ability of the product to withstand stretching during use. If the item is unqualified, the plastic packaging bag (film) is easily broken and damaged during use.

3. Degradation performance can be divided into photodegradation type, biodegradation type and environmental degradation type according to the degradation type of the product. The degradation performance reflects the product's ability to be accepted by the environment after use and disposal. If the degradability is good, under the combined action of light and microorganisms, the plastic packaging bag will rupture, differentiate and degrade, and become fragments. This is accepted by the natural environment; if the degradability is not good, it will not be accepted by the environment. Thereby forming "white pollution".

At present, foreign countries have strict regulations on plastic packaging bags for food packaging, stipulating that ordinary food plastic packaging bags cannot be used for food with a temperature higher than 50 degrees Celsius; food packaging must be marked with the temperature that can withstand. There are no domestic regulations in this regard, which leads to certain unqualified plastic packaging bags that are harmful to people's health.