1, glass
Of all materials, glass is relatively the safest. Glass cups are usually made of inorganic silicates, which are fired at a high temperature of more than 600 degrees. Because of their relatively stable chemical composition, they will not produce harmful substances in the firing process. Moreover, the glass surface is smooth and easy to clean, and bacteria and dirt are not easy to breed on the cup wall. It's the first time to use the cup, so I'm afraid the boiling water will burst. You should pour some hot water first, gently shake the preheated glass, and then pour hot water for later use.
2. Ceramic cups
Ceramics, like glass cups, are fragile, so they are not suitable for going out and being used in fixed places. Ceramics are widely used in tableware and other places, so the material is very safe. Qualified ceramic cups can not only be filled with water normally, but also be heated by pouring a glass of milk in the morning.
Selection method of water cup
First of all, look at the luster.
A good container has a shiny appearance and a soft surface, while a poor container looks a little dark.
Second, look at the degree.
Whether the bottle wall is transparent and pure. Inferior plastic products will be sticky and astringent if they are not cleaned.
Third, smell it.
Inferior products have a pungent smell, even if they are filled with drinks or food, they can smell the smell from the outside without opening the lid.
Fourth, look at hardness.
A good container is thick and hard, and it will not be excessively deformed if it is pressed inward by hand.