The key in the door and window seals. Sealing effect, strip plays a key role. Steel doors and windows on the market with the seal material is generally modified PVC, which plays a key role is to join the plasticizer, the relatively stable phosphorus plasticizer dioctyl phthalate, dibutyl, but the market higher prices. So some manufacturers to replace injustice with some cheap stuff: waste oil, the rest of the oil refinery base, etc., to the user later planted a big risk. Special Note: Optional steel doors and windows seal should pay attention to the following aspects: 1, with the nose smell the smell is normal PVC material a little alcohol taste, very small, almost smell. 2, in the summer, when doors and windows sealed with the profile contact surface is stained color, yellow oil leakage. 3. Look proportion. The same amount of high-quality feel strip doors and windows sealed to light, on the contrary to be heavier. Regular manufacturers generally use a small proportion of calcium carbonate as a filler, some manufacturers are using talc, GCC, to increase the proportion of the product. Because when sales are denominated by weight. Hazard inferior steel doors and windows sealed: 1, environmental, smelly, polluting the air. 2, reduce tightness. Poor quality of the sealing strip containing plasticizers or use inferior substitutes, hard winter, easy to aging, shrinking. A gap between the glass and profiles, causing leaks, leaking dust. Many users are often found inside the rainy plastic window layering parts out of the red liquid is between the window glass and sealing strip steel liner after corrosion caused by water. Not only greatly reduce the aesthetic plastic window, but also greatly affect the life of the doors and windows. Doors and windows sealed, although the proportion of small, but the effect can not be discounted. Inferior seal doors and windows not only environmentally friendly, containing the smell, your body will cause harm, pollute the air. With the prices of various petrochemical products continues to rise, some irresponsible manufacturers began to unfair competition from raw material aspects (called shoddy, shoddy). The key lies in the actual door seals, seal or bad seal plays an important role. Market with the seal material is generally modified PVC in soft PVC key role in its inside is nothing more than adding plasticizers good or bad, there are currently more stable phosphorus plasticizer dioctyl fat, two small fat. But now the market price is high, some unscrupulous traders use some other cheap stuff instead (waste oil, the rest of the oil refinery base, etc.) to consumers is a big risk.