WHAT’S THE DIFFERENCE BETWEEN BOROSILICATE GLASS AND SODA-LIME GLASS?
Many companies choose to use soda-lime glass for their glass products because it is less expensive and readily available. It accounts for 90% of manufactured glass worldwide and is used for items like furniture, vases, beverage glasses and windows. Soda lime glass is susceptible to shock and does not handle extreme changes in heat. It’s chemical composition is 69% silica (silicone dioxide), 15% soda (sodium oxide) and 9% lime (calcium oxide). This is where the name soda-lime glass comes from. It is relatively durable at only normal temperatures.
IS BOROSILICATE GLASS PERFORMANCE SUPERIOR?
The coefficient of soda-lime glass is more tan double that of borosilicate glass, meaning it expands more than twice as fast when exposed to heat and will break very quickly. Borosilicate glass has a much higher proportion of silicon dioxide in comparison to regular soda lime glass (80% vs 69%), which makes it even less susceptible to fractures.
In terms of temperature, the maximum thermal shock range (the difference in temperatures it can withstand) of borosilicate glass is 170°C, which is about 340° Fahrenheit. This is why you can take borosilicate glass out from the oven and run cold water over it without shattering the glass.
*Fun fact, borosilicate glass is so resistant to chemicals, the boron in the glass makes it less soluble, preventing any unwanted materials from leaching into the glass, or the other way around. In terms of overall performance, borosilicate glass is far superior to regular glass.
IS PYREX THE SAME AS BOROSILICATE GLASS?
You’ve probably heard of the brand name ‘Pyrex’. However, borosilicate glass is not the same as Pyrex. When Pyrex first hit the market in 1915, it was initially made from borosilicate glass. Invented in the late 1800s by German glassmaker Otto Schott, he introduced the world to borosilicate glass in 1893 under the brand name Duran. In 1915, Corning Glass Works brought it to the U.S. market under the name Pyrex. Since then, borosilicate glass and Pyrex have been used interchangeably in the English-speaking language. Because Pyrex glass bakeware was initially made of borosilicate glass, it was able to withstand extreme temperatures making it the perfect kitchen staple and oven companion, contributing to its huge popularity over the years.
Today, not all Pyrex is made of borosilicate glass. Some years ago, some switched the material in their products from borosilicate glass to soda-lime glass, because it was more cost-effective. So we can’t really be sure what is actually borosilicate and what is not in Pyrex’s bakeware product line.
WHATS BOROSILICATE GLASS USED FOR?
Due to its durability and resistance to chemical changes, borosilicate glass has traditionally been used in chemistry labs and industrial settings, as well as for kitchenware and for lighting as well.
Because of its superior quality, it is often priced higher than soda-lime glass.
It’s better for the environment. Plastic are terrible for the environment. They are made from petroleum, and they almost always end up in either a landfill, lake or ocean. Only 9% of all plastic gets recycled. Even then, often times the process of breaking down and reusing plastics leaves a heavy carbon footprint. Since borosilicate glass is made from naturally abundant materials that are more easily acquired than oil, the environmental impact is also smaller. If handled with care, borosilicate glass will last a lifetime.