When buying a plastic cup, first open the plastic plate, smell whether there is a smell, if there is a clear plastic smell, do not recommend buying.Also look at the triangle logo on the bottom of the cup, which is usually marked "05" to indicate that the material is PP(polypropylene).ThWhen buying a plastic cup, first open the plastic plate, smell whether there is a smell, if there is a clear plastic smell, do not recommend buying. Also look at the triangle logo on the bottom of the cup, which is usually marked "05" to indicate that the material is PP(polypropylene). The material is done glass melting point at 170 ℃ ~ 172 ℃, has good heat resistance, and has stable chemical properties.