First, the role of packaging on the environment Packaging has a dual role to the environment. One is positive protection and the other is negative pollution. At present in our academic field or in the field of packaging and environmental protection, many people, in addition to studying the contribution and role of packaging in goods, are more concerned with the negative impact of packaging on the environment - pollution. In fact, packaging has a considerable role in the protection of the environment, and this is often forgotten in the current people's visual and discussion topics. Recently, when the author visited the United States to inspect the packaging problem, he unexpectedly discovered that the beautiful urban environment in the United States is largely due to their full attention and research on packaging. The best explanation for packaging's contribution to environmental protection may be their agricultural and sideline products and building materials packaging. U.S. agricultural and sideline products are almost all packaged, and sales packages from small pouches to large-scale packaged transport packages are reflected in agricultural and sideline products (vegetables, etc.), leaving no surplus residue of agricultural products in the city. Before the agricultural and sideline products reach the city for sale, they are processed and packaged in advance on the farm or place of production. The 100% edible parts enter the shopping mall or enter the city, minimizing the inedible waste, so that the urban pollution source can be eliminate. What is more surprising is the building materials packaging in the United States. The pollution of any city, to a large extent, is the pollution caused by the circulation and use of the construction industry and building materials. Such pollution has been well solved in the United States through scientific packaging. The following focuses on the status quo of building materials packaging in the United States. Second, the green packaging in the building materials market 1, the transaction method In the United States a lot of building materials market, a wide range of building materials and packaging is very scientific. They concentrate their building materials on one or a few large building materials markets in the city. When buyers and sellers conduct transactions, the delivery and price allocation are separately carried out in different directions in the same market, because the consumption of building materials is large and the varieties are also More often than not, it is difficult to trade in every type of building material storage. Only after listing the product types and specifications in more than one place, go to the fixed place and then invoice. But many of them are conducted in the market, which is very similar to our supermarket shopping. 2, the packaging form of building materials, many forms, different sizes. Mainly reflected in the following areas: In the diversity of structural forms, it is more determined by building materials with different shapes, different materials, and different characteristics. This mainly depends on the diversity of building materials themselves. Bag format: including plastic woven bags, paper-plastic composite bags and nylon mesh bags. Plastic woven bags: This type of bag-type packaging is mainly used for the packaging of fine sand and lime, and some for asphalt packaging. Paper-plastic composite bag: It is mainly used for the packaging of cement, lime and powder. Nylon mesh bag: mainly used for packaging of coarse sand or granular stone. Metal drums: There are square buckets and drums. This form of packaging is primarily used for the packaging of adhesives and decorative liquid materials. Strapping packaging form: mainly metal and non-metallic strapping. For wood, metal materials and plastic plate and tubular building materials packaging and strapping. 3, loading and unloading and stacking package loading and unloading, almost all mechanical forklift loading and handling. Tray: As a heavy or fixed structure of building materials packaging, such as stone bricks, door frames, glass, etc., are used in the form of pallet packaging, the tray is fixed with a stretch film. Stacking form: In order to facilitate the purchase and loading and unloading, it usually has a multi-layer shelf, which makes stacking stable and easy inventory management. Many markets have specialized stacking brackets for building materials, which can reach a height of more than ten meters. Transportation of incoming and outgoing goods is achieved by special machinery that can be lifted and lowered. 4, the fixed form of packaging fixed form of building materials packaging shrink film, self-adhesion film and plastic rope. There is also a small amount of strapping used for fixing. Shrink film fixation is mainly used for those products or materials that require waterproofing and surface protection against scratches, such as wood products, aluminum, copper products, or other metal or plastic components for surface decoration. Self-adhesive film is mainly used for bricks, processed marble, ceramic tiles and other long-finished products with fixed structures. (To be continued)