Fourier Transform Infrared Analysis of Varnish Curing Kinetics
ATR-FTIR cure kinetics tracking links acrylate double bond conversion percentages directly to monomer migration safety and substrate blocking performance.
Diamond ATR
Analytical Interface
Internal reflection spectroscopy provides a chemical fingerprint of surface coatings on paper substrates by measuring infrared absorption. The diamond atr crystal facilitates this by pressing firmly against the film or polymer layer during analysis. Photons travel through the high refractive index diamond into the sample where the depth of penetration remains confined to a few microns.
This controlled geometry ensures that only the coating chemistry generates the spectral signal while the underlying cellulose fibres exert minimal influence on the reading.
Operational Calibration
Precise contact between the hard carbon facet and the packaging material governs the quality of the gathered data. Uneven pressure distribution creates spectral artifacts that distort the baseline or weaken absorption peaks for common additives like slip agents or heat seal layers. Operators verify the clamping force before every scan to maintain consistency across batches of extruded board.
A lack of uniform contact results in incomplete data sets that fail to identify low concentration waxes or functional binders within the coating matrix.
Material Discrimination
Quantitative identification of specialized polymer laminates depends on the high mechanical durability of the crystalline surface. Hardness allows the probe to withstand repeated contact with abrasive mineral fillers like clay or calcium carbonate without degradation of the collection optics. Such durability prevents the need for frequent recalibration or sensor replacement even when shifting between matte and gloss finishes.
Superior thermal stability ensures that measurements remain accurate even if the substrate retains heat from the laminating process.