Extrasil - ES Quartz

What makes Extrasil (ES) Quartz a superior material for flow cells and precision cuvettes.

Unique Material Available Through NSG Precision Cells: A Member of The Tosoh Family

One very common question we receive is, "What is ES Quartz?" In  short, this is a unique brand of quartz, superior to standard UV grade quartz in purity,usable range, and other characteristics. "ES" stands for ExtraSilQuartz, and  is made in Japan, at our ISO 9001 certified factory. The New York Tosoh office, NSG Precision Cells, is the main distribution hub for Extrasil (ES) products.

Extrasil (ES) quartz has been available from NSG Precision Cells/Tosoh for many years.

NSG Precision Cells /Tosoh is the only cuvette and flow cell manufacturer who also manufactures their own raw material.

Benefits of Manufacturing ES Quartz In House

The ability to make our own quartz material gives us complete control over our product manufacturing from start to finish.  As a result, we do not have to rely on any sub-contractors or suppliers for any of our manufacturing needs. From manufacturing the Extrasil ES Quartz to the finished flow cell, the project does not leave our hands.

Our customers can enjoy peace of mind, knowing that an agreement with NSG Precision Cells doesn't involve another raw material supplier. As such, we will never have to worry about prices, long lead times, if a supplier goes out of business, etc.

Optical Properties

One of the biggest benefits of using Extrasil ES Quartz is its superior optical properties.  ES Quartz is a Suprasil®1 equivalent and some scientists say it gives even better results than Suprasil®1.  Extrasil ES quartz excels in performance in the far UV and visible wavelength ranges.

Since Extrasil ES Quartz is a synthetic fused silica quartz, the level of impurities are almost zero.  Researchers can rest assured that any products made with NSG Precision Cell's Extrasil ES material will have highly optimized optical properties, and provide extraordinarily accurate and reproducible results.

Also, Extrasil ES quartz has superb resistance to high energy UV laser radiation,which means the material will not be easily damaged.  For this reason many companies are using Extrasil ES quartz in their optics systems.

The transmission range for Extrasil ES quartz is from 170 - 2,500 nm.  In this range Extrasil ES quartz transmits at over 80%.  ES quartz can also be easily coated with an anti-reflection (AR) coating to enhance the transmission properties beyond this transmission range. Rather than having 80% transmission, which is already very high, you can get a 90% transmission or better with AR coating.

Thermal Properties

Strain Point:                °C     970
Annealing Point:          °C     1,080
Softening Point:           °C     1,720

Thermal Expansion:    x10-7 °C-1     4.7

Specific Heat: 20 °C    J kg-1 K-1     749
                     500 °C    J kg-1 K-2    1,122
                     700 °C    J kg-1 K-3    1,201
                     900 °C    J kg-1 K-4    1,243

Thermal Diffusivity:     19 °C    x10-7 mz s-1     8.5
                                  500 °C    x10-7 mz s-2    7.8
                                  700 °C    x10-7 mz s-3    8.2
                                1000 °C    x10-7 mz s-4    9.6

Thermal Conductivity:  19 °C    W  m-1 K-1     1.38
                                    500 °C    W  m-1 K-2    1.93
                                    700 °C    W  m-1 K-3    2.17
                                  1000 °C    W  m-1 K-4    2.55

Refractive Index

n_C = 1.456005 at 656.3 nm

n_d = 1.458434 at 587.6 nm

n_F = 1.462841 at 486.1 nm

n_g = 1.466730 at 435.8 nm

n = 1.508609 at 248 nm

At 20°C, 1 bar atmospheric pressure

Accuracy: ± 3 x 10^-5

Chemical Compatibility

Please see our ES Quartz Chemical Compatibility page.

Extrasil ES Quartz Impurities

Al     Ca      Cu      Fe       Na      K          Li        Mg       OH
0.1    0.1    0.01    0.05    0.05    0.05    <0.01    <0.01    1000

About NSG