Peter, As discussed during your visit on Friday, 14.10.11, we herewith send you a statement about the use of your refractometers at our production-facility.
LONZA produces a special prepolymer in a dedicated plant at the Visp site, where the refractive index (at 110°C) is used as a control of the polyme rization-rate and as stop-signal for the reaction. Since this process is highly exothermic, the control of the reaction-rate is very important. The end-product goes to high performance applications and has very tight specifications.
In the beginning, the refractive index was measured with Abbe style instruments. Two main problems appeared during their use: Varying reading of the results by the different plant operators and pollution of the instruments due to the resin-like consistence of the product. Both resulted in regular-appearing “Out of spec” batches.
After long evaluation for the replacement of one Abbe style instrument, we decided to purchase one J257 automatic refractometer. After start-up we learned, that this device is extremely simple to use, has an excellent level of accuracy and can be cleaned in a very easy and effective way. After two years of operation, we just had one interruption due to a defective temperature control of the cover. Based on these very satisfying results, we decided this year to replace also the backup Abbe style instrument by a second Rudolph refractometer.
As we are very pleased with your instruments, you can consider us as reference customer.

With best regards,
Mazotti Roger, B.sc. Head of production LSIPH