Materials and technology of green packaging

With the development of economy and the improvement of living standard, more and more packaging waste can not be recycled. Especially in the 1970s, after people used plastic packaging, more and more plastic packaging products and pollutants could not be recycled, which caused more and more serious environmental pollution. This is one of the reasons why we discuss the material, printing and process manufacturing of green packaging and its importance. Today, the editor of China paper industry network takes you from green packaging, and introduces the related technology in detail.

What is green packing material? In a broad sense, we are in the production, manufacturing, use and recycling of packaging materials, which are harmless to human health, have a good protection role in the ecological environment and recycling packaging materials. For example, polyester, ethanol or diethylene glycol, polypropylene, corrugated paper, edible glutinous rice paper, corn paper, edible recycled fresh-keeping paper, paper packaging products and paper-made handbags, paper cups, paper rice boxes, etc. In short, various kinds of plastic products packaging and raw materials which can be dissolved or polymerized to protect ecological degradation. The degradable plastic products packaging materials are all kinds of plastic products and other packaging materials which are degraded by photosensitizer, and degraded by biological or chemical substances. This is an important aspect of choosing packaging materials.

As for the printing of packaging materials, it is another important problem of green packaging. Especially ink is one of the important raw materials and important means of our printing. Ink is composed of pigments, binder, solvents and auxiliary materials, among which pigments and solvents have inorganic and organic compounds, and heavy metals damage human body the most. The metals such as lead, chromium, pickaxe and mercury which are insoluble in water and medium are the most toxic in pigment, and cannot be used in food packaging, children's appliances and packaging printed in flat, concave, convex and screen printing. Biphenyl gum in organic matter will lead to cancer substances. Acetone, toluene, methanol and some aromatic solvents, toxic gases and corrosive solvents in the solvent can not be applied. That is, pigments, binders and solvents in ink are important raw materials for the manufacture of various kinds of ink. We can not use heavy metal as pigment, can use water-based binder, Western Europe, Japan and Taiwan have promoted water-based UV binder and ink as pigments.

Guangdong has studied water soluble liquid photosensitive resin in the 1960s, which can be used to make water-based UV light oil and water-based UV ink. The manufacturing cost and process are simple, and are hardened (dried) by irradiation of less than 380 degrees of light wave. The light source is ultraviolet light can be installed on the printer, but it should cover the seal to prevent the eyes from burning. At that time, we studied that the liquid resin version used black light tube (i.e. 3-5 agricultural sterilization lamps) as the light source, which can reduce the harm of ultraviolet light to human body, and its cost is very cheap and the technology is extremely simple. But the plastic packaging such as plastic bags, plastic rice boxes are not soluble. It is produced by blowing and pressing toxic polychloroethylene resin, which is characterized by simple technology, low cost and convenient carrying. But the biggest disadvantages are pollution and non renewable. If we use scientific attitude and advanced technology, we can also achieve the purpose of simple technology, low cost and convenient carrying.

For example, plastic cups, plastic dishes, plastic rice boxes, plastic bags for packaging items are made by heating and dissolving plastic particles, blowing with foaming agent and plasticizer. The process is simple and the cost is low. However, it is not conducive to environmental protection and cannot be regenerated, which will cause a lot of environmental pollution. If we use paper or recycled pulp and spray a layer of edible mobile paraffin, the food which can be fresh and sealed with edible paraffin can be kept fresh for more than 2 years (to be sealed by spraying instead of wax), and finally pressed with recycled pulp. The process and price are relatively simple and cheap (the paper cup and paper rice box are made into white board and then pressed The price is much higher, of course, if it is made.

When we change the process to make pulp by turning paper, the packaging can not only reduce the price, but also can be used continuously. (equal to our process of turning toilet paper), if we spray a layer of edible mobile paraffin (pay attention to whether the spray is over waxed, the effect of spraying and waxing is different) is a cheap and material and can be sought. In quality, many of the paper is made of wood pulp and rag, and its fiber is long and the quality is guaranteed. For example, we use the technology of fresh paper to blow some (0.03-0.05mm) of the fresh-keeping paper to replace the existing multi-layer metal or multi-layer tin foil beverage box (Tetra Pak beverage packaging box), and then spray a layer of edible mobile paraffin to replace the multi-layer composite beverage box, so as to keep fresh and increase its stiffness.

In short, we can further explore the materials and printing methods of green packaging through scientific methods, and do our best to protect nature!

推薦連結:銀雪魚