BOROFLOAT® 33(BF33)High Borosilicate Glass
German SCHOTT micro-float type 3.3 borosilicate flat glass. Standard sheet size 1,150 × 850 mm, with original manufacturer material certificates and batch traceability documents available per project.
Guangzhou Lighting Glass Co., Ltd. is a preferred partner of SCHOTT in China and an official BOROFLOAT® distributor, supplying genuine BOROFLOAT® 33 to R&D, equipment manufacturing and volume purchasing projects. Original manufacturer material certificates and batch traceability documents are available per project.
BOROFLOAT® 33 is produced with SCHOTT's micro-float process and combines relatively low thermal expansion, high visible-light transmission, good chemical stability and mechanical durability. Float sheet has a stable flat form, making it suitable for viewing windows, optical supports, laboratory components and industrial equipment windows.
Material selection requires confirming operating temperature, wavelength band, thickness, outline and surface requirements together. At the material purchasing stage we can assess cutting, hole positions, edges, lapping and polishing, cleaning and inspection in parallel, reducing later process rework.
| Material type | 3.3 borosilicate float glass |
|---|---|
| Optical properties | Refractive index nd = 1.471 (587.6 nm); Abbe number νe = 65.41; dispersion nF − nC = 71.4 × 10⁻⁴ |
| Transmission band | Approximately 250–2,800 nm; actual transmission varies with thickness and wavelength |
| Stress-optical coefficient | 4.0 × 10⁻⁶ mm²/N |
| Coefficient of thermal expansion (CTE) | 3.25 × 10⁻⁶ K⁻¹(20–300°C) |
| Specific heat capacity | 0.83 kJ/(kg·K)(20–100°C) |
| Thermal conductivity | 1.2 W/(m·K)(90°C) |
| Glass transformation temperature Tg | 525°C |
| Maximum operating temperature | Long-term use (≥10 hours) 450 °C; short-term use (<10 hours) 500 °C |
| Density | 2.23 g/cm³(25°C) |
| Young's modulus | 64 kN/mm² |
| Poisson's ratio | 0.20 |
| Knoop hardness | 480(HK0.1/20) |
| Water resistance | HGB 1(ISO 719 / DIN 12111);HGA 1(ISO 720) |
| Acid resistance | Class 1 (DIN 12116) |
| Alkali resistance | A 2(ISO 695 / DIN 52322) |
Specifications presented together so purchasing and engineering staff can confirm them quickly.
0.40 · 0.50 · 0.60 · 0.70 · 1.00 · 1.10 · 1.50 · 1.75
2.00 · 2.25 · 2.75 · 3.30 · 3.80 · 5.00 · 5.50 · 6.50 · 7.50 · 8.00 · 9.00
11.00 · 13.00 · 15.00 · 16.00 · 18.00 · 19.00 · 20.00 · 21.00 · 25.40
All thicknesses above are in mm. Stock quantity, tolerances, cut sizes and lead times are confirmed at the enquiry stage.
Beyond material supply, we can provide precision glass cutting, CNC cutting, waterjet cutting, CNC engraving, drilling, profile edge grinding, glass wafer processing, lapping and double-sided polishing to drawing, together with cleaning and dimensional and appearance inspection.
Processing capability must be confirmed for manufacturability against dimensions, thickness, quantity, hole positions, edges and surface requirements.
Shown to illustrate volume processing, work-in-progress and parts awaiting inspection; actual parts follow the customer drawing.


Selection still needs to consider temperature variation, load, optical band, chemical environment and downstream processing requirements.
Yes. Genuine BF33 material can be supplied with a material certificate and batch traceability documents per purchasing project; the exact documents are confirmed with the ordered specification and batch.
Thicknesses currently available on request span 0.40–25.40 mm, covering the 28 thicknesses listed on this page. Stock quantity, standard sheet sizes, tolerances and lead times are confirmed item by item by thickness.
Yes — R&D prototyping, small-batch validation and volume delivery. Please provide the material grade, dimensions, quantity and key acceptance requirements so we can assess material yield and process route.
Yes. We can assess cutting, CNC engraving, drilling, profile edge grinding, wafer processing, lapping, double-sided polishing, cleaning and inspection.
Please provide thickness, length and width or outline, quantity, tolerances, hole positions, edge condition, surface quality, clean packaging, application and required lead time; include a drawing if available.
Provide the material grade, dimensions, quantity and key acceptance items, and we will match cutting, polishing, cleaning and inspection to the material's characteristics.