CategoriesShow all

Ask Qorpak


What is Borosilicate Glass?

Ever wondered why some glass can go from freezer to oven and back again while others can’t? A thorough explanation would require a semester in physics, studying density’s relation to structural integrity and coefficients of thermal expansion, but the short answer lies in its composition.

Some glassware, especially the quality stuff, is made with special ingredients that offer unique characteristics. Borosilicate glass is resistant to temperature change because it does not expand like ordinary glass. It has a smoother transition between temperatures, and can even withstand different temperatures at the same time. That’s why a glass tray with cold casserole leftovers can go straight into a 350-degree oven and does not shatter when dropped into a sink full of cold water.

Common silicate glass, the material used in window panes and iced tea glasses, is a mixture of sand, sodium-carbonate and limestone. Add boric oxide to it and, you guessed it, borosilicate glass is created. A +5% infusion of boron provides a less dense product with a higher melting point, making it useful for lots more than kitchen cooking.

Uses of Borosilicate Glass

Borosilicate is the material of choice for many laboratories due to affordability--quartz products are more expensive. Qorpak distributes a variety of borosilicate glassware products for lab use, including tubes, beakers and graduated cylinders.

As mentioned earlier, borosilicate glassware can be exposed to two temperatures at the same time. Laboratories are able to heat one end on a hotplate or under a flame without worrying about the other end. It has a maximum working temperature of 515 degrees Fahrenheit, though does not melt until 550 degrees. That meets the demand of most laboratories.

Many scientific lenses require a glass that remains both clear and strong when exposed to heat. Borosilicate microscope lenses and microscope slides allow scientists to analyze tiny organisms right under their nose and astronomers use it in telescopes that bring far off galaxies much closer to home. Similarly, the late Space Shuttle Discover flew 39 missions with borosilicate thermal insulation tiles to protect it from extreme lows during orbit and extreme highs upon reentry.

It even has a leading role in the arts. Stage lights can reach high temperatures during a three-hour show. Borosilicate glass is used in both the spotlights that keep performers lit onstage and the flashlights that help them scurry around the set after the curtain falls. The glass guitar slides that bend notes during blues and rock ‘n’ roll solos are even called boro for short. Borosilicate glass plays many parts in the show.

It is also popular for art construction. Glass sculptors and lampworkers use this “hard glass” to create everything from little artisan beads to huge museum exhibits.

Most of the borosilicate glassware that we offer at Qorpak is for scientific use. Our Type I Borosilicate Glass Sample Vials assures the contents integrity. Vials are ideal for storing and sampling small amounts of liquid and powders. Choose clear for maximum visibility or amber, cobalt blue or green for protection from UV rays. Cobalt blue and green vials are commonly used for aromatherapy and essential oil packaging.