Applications for the Paper Industry: SPECTRO PHOENIX II Measures the Thickness of Silicon Coatings

July 25, 2007

Application Report documents use of the SPECTRO PHOENIX II to monitor silicon coatings on paper, clay-coated paper and plastic
Kleve, July 2007 – Every year, several billion square meters of paper are coated with silicon release and barrier coatings throughout the world. In order to ensure a uniform quality of the coated paper, it is necessary to regularly measure the thickness of the silicon during production, measured as the coat weight. As one of the leading manufacturers of X-ray fluorescence instruments, SPECTRO has developed applications utilizing the SPECTRO PHOENIX II instrument for this procedure. The robust and inexpensive benchtop XRF spectrometer is well suited to the monitoring of silicon coat weights down to less than 1 mg/m² without the use of a helium purge, and can be consistently operated even in harsh production climates.  The applications have been documented by SPECTRO in an Application Report. The report describes the measuring arrangement and the results from several test series. The document can be downloaded now, free-of-charge, from www.spectro.com. 

Silicon release coatings are used to make paper surfaces anti-adhesive. Paper coated in this way is utilized in everyday life as baking paper or on tapes, the back side of stickers, band-aids (adhesive plasters) and other adhesive surfaces. The industry uses release paper as a carrier for thermosetting liquids: These are set on the paper, then removed and laminated onto other carriers. This procedure is used for the manufacture of imitation leather and textile coatings, for example. The silicon coatings are typically one to two micrometers thick, which corresponds to an application weight of one to two grams per square meter. Even small variations in the thickness of the silicon have a large effect on the material properties. With the SPECTRO PHOENIX II, paper manufacturers are able to monitor the silicon coatings during the production process. In addition to release coatings, silicon coating are used as an air barrier in food packaging papers and plastics, as well as a sealant over printed packaging material and printer paper.

The analytical procedure documented in the application report is very user friendly, simple enough for non-technical operators: The responsible employee simply cuts approximately five by five centimeter paper samples from different locations on the paper roll and places them in the spectrometer. The "one-button" measuring procedure is started using an easily understandable touch screen. The instrument displays the exact coating thickness within just a few minutes. In the Application Report, SPECTRO describes three test series detailing the analytical performance for silicon coatings of varying coat weight on paper and clay-coated paper. The SPECTRO PHOENIX II delivers extremely accurate measurement results in all three cases, with deviations of less then one percent.

About SPECTRO:
SPECTRO is one of the worldwide leading suppliers of analytical instruments for optical emission and x-ray fluorescence spectrometry. As a member of the AMETEK Materials Analysis Division, SPECTRO manufactures advanced instruments, develops the best solutions for strongly varying applications and provides exemplary customer service. Innovation, instrument concerns and customer relations are its main activities. From its foundation in 1979 until today, more than 26,000 analytical instruments have been delivered to customers around the world.

AMETEK, Inc. is a leading global manufacturer of electronic instruments and electric motors with an annual turnover of approximately 1.8 billion US$. AMETEK’s corporate growth plan is based on four key strategies: Operative excellence, strategic acquisitions and alliances, geographic and market expansion as well as new products. AMETEK’s common stock is a component of the S&P MidCap 400 Index and the Russell 1000 Index.

Please contact Tom Milner for additional information, Tel: +49.2821.892-0, 
Fax: +49.2821.892-2200, E-Mail: spectro.info@ametek.com