'Lean' laser for exact measuring into the nano range

Fritsch extends particle sizer A-22 with dry dispersion

With the A-22 NeXT, laboratory instrument pioneer Fritsch, offers laser particle analysers that are particularly impressive due to its ease of use. With their minimised design, the A-22 NeXT is easy to operate and clean, low-wear and practically maintenance-free. The measuring instruments deliver precise results in the nano and micro range in under a minute. Fritsch recently added a dry dispersion unit to the modular solution.

With its extremely wide measuring range of 0.01 to 3,800 μm, the A-22 NeXT Nano offers maximum accuracy even for the smallest particles. The A-22 NeXT Micro with a measuring range of 0.5 – 1500 μm is perfectly suited for all measuring tasks. Both instruments work with just one laser and also the A-22 NeXT Nano does not require an additional light source for backscattering. Thanks to its state-of-the-art electronics with fast, high-resolution sensors, the A-22 NeXT records the signals from all detector elements simultaneously. As a result, it always delivers the entire scattered light distribution at the same time and transmits it to the associated software several hundred times per second. Due to the angled arrangement of the measuring cell to the laser beam, a significantly larger scattering angle range can be recorded than with comparable instruments. As a single image is sufficient for the entire measuring range, the A-22 NeXT is extremely fast; the total measuring time, including cleaning, is less than one minute for most measurements.

Like all laser particle sizers from the traditional manufacturer, the A-22 NeXT works with the reverse Fourier design invented by Fritsch, which has largely established itself as the market standard. The advantage: no additional optical elements are required between the measuring cell and the detector. This means that the particularly compact particle analyser requires few components and virtually no moving parts. As a result, the A-22 NeXT is low-wear and virtually maintenance-free. Cleaning the device is also extremely easy thanks to its simple design with few components that can be removed without tools. To make operation particularly easy for users, Fritsch has equipped the A-22 NeXT software with predefined SOPs for almost all common measuring tasks.

Customers can modify these flexibly to suit their requirements or create their own SOPs. When the SOP is selected, the dispersion process and duration, measuring frequency and time intervals are set automatically. The result: reliably reproducible measuring processes.

New module dry dispersion

The A-22 NeXT was developed according to a modular concept. For example, customers can choose between a dry and a wet dispersion unit depending on the individual task. In the wet dispersion system, a powerful centrifugal pump with adjustable speed ensures stable measurement. The pump also transports heavy particles and allows the sample material to be distributed quickly and uniformly throughout the entire circuit. A dry dispersion option has recently been added for materials that react in water or other liquids. This can also be used for larger sample quantities in the range from approx. 1 cm³ to greater than 300 cm³. In dry measurement, the sample material is transported from the vibratory feeder via the suction funnel of the dry measuring cell, where it falls directly into a Venturi nozzle operated with adjustable compressed air. Agglomerates are broken down as they pass through the nozzle. The particle size distribution is then measured directly in the laser beam.