Properties
The phenomenal properties of temper borosilicate glass 4.0 make it the best monolithic Class E fire resistant glass
General Property
Floated 4.0 borosilicate glass is as flat as ordinary soda-lime. Density of borosilicate glass is low. It is approximately 10% lighter than soda-lime glass. It can be applied where loading is an issue.
Composition of borosilicate glass gives no chance for the formation of NiS crystal during melting in the float line. Nickel sulphide crystals are proven to be the source of glass self-break. Hence, thermal tempered borosilicate glass 4.0 does not self-fracture. It is risk free of spontaneous glass fracture. Moreover, the glass does not require heat soak test. This reduces production cost and shortens delivery time.
Tempered borosilicate glass behaves like ordinary tempered soda-lime glass when breaks. It fractures into small glass fragments.
It stays transparent under high temperature when burning. People can monitor what is happening in neighbor. Finding ways to evacuate safely and promptly from buildings on fire will be much easier. Glass composition is free of sulfur. Ingredients are all natural. Low carbon foot print glass. It is environmental friendly.
Thermal Property
The characteristic of fire resistant of borosilicate glass is majorly due to its extremely low coefficient of thermal expansion 4.0×10-6 K-1. It is only 1/2 ~ 1/3 to ordinary soda-lime glass. This unique thermal property greatly reduces heat stress and thus, withstands temperature differential. The glass is shatter proof under drastically change of thermal attack.
Below is a table of Time Vs Temperature of a typical fire test.
| Time (min.) | 5 | 10 | 15 | 30 | 60 | 90 | 120 | 180 |
| Temperature (℃) | 557 | 657 | 719 | 820 | 926 | 987 | 1028 | 1091 |
It takes only 5 minutes to rise from room temperature to 557℃. Thermally tempered borosilicate glass 4.0 easily withstands such a dramatic temperature changes. It is shatter proof under thermal shock. The superior thermal stability is the key to resist the heat impact. Moreover, borosilicate glass can also support by itself under a fire due to its high softening point.
Mechanical Property
Borosilicate glass has high mechanical strength. It gains much stress after tempering and mechanical strength is significantly increased.
Borosilicate glass 40 is harder. It shows high ability of anti-abrasive and thus, scratch resistant. This characteristic is extremely useful if washing and wiping are done by improper materials.
The glass bears low fragility due to its very low content of alkaline metal oxides. It reduces the risk of breaking during handling, transportation and installation.
The flow rate of high viscosity borosilicate glass is very low. This behaviour also plays a part in fire resistant.
Chemical Property
There is very low alkaline content in borosilicate glass composition. The alkali is very stable and the glass behaves very low alkali diffusion. It is anti-corrosive and weather proof. It resists daily cleaning and washing agent and acidic rain. Chemical attack is no more an issue.
Optical Property
Borosilicate glass is anti-reflective and allows more light intensity passing through. It has higher light transmission than soda-lime glass due to its lower iron content composition. Lower residual reflection allows very high transparency. It is optical distortion free and inert to UV. The purity of raw materials ingredients' makes it superior visual and optical clarity. It is also high transparency in the near IR and UV range.
