PVC layflat hose-What is the reason for PVC layflat hose to make hard black？

Maybe you will smell the smell of PVC layflat hose. You must be familiar with PVC layflat hose, which is used in many parts of our life, such as family cleaning, family car washing, garden irrigation, gas and dust transportation. But some just buy PVC layflat hose in the sun for two days to find the smell of black and stinky, why this bad situation, let us from the raw materials of PVC layflat hose to analyze why some garden tubes will be black and stinky.

The raw materials of PVC layflat hose are fixed, and the raw materials include PVC resin powder, paraffin wax, calcium powder and so on. A good PVC hose does not add calcium powder too much. The more quality the calcium powder adds, the less the quality, the less or not the addition, which means that the cost of PVC layflat hose is high. When buying PVC layflat hose, try to buy the less calcium powder as much as possible is not too big, so PVC layflat hose will not be black hair odor or price is very expensive.
When you buy PVC layflat hose, you must smell the taste first, then fold the PVC layflat hose to see its flexibility, and the third is in the sun for a day, and the fourth is in the refrigerator to see if PVC layflat hose is hard.