Colour, Brightness and Opacity (Paper)

These surface optical properties are used in most specifications to define the visual quality of plastic, paper and board. The tests can be made on a range of materials including plastic, tissue, paper, copy paper, coated board, carton board and papers for most printing applications.

Technidyne Colourtouch PC Spectrophotometer

CIE whiteness, brightness, L*a*b* colour and opacity are all measured using a Technidyne Colourtouch PC spectrophotometer with a range of light sources.

Smithers Pira's UKAS, ISO 17025 accredited testing is performed to the following British standard and International standards: whiteness to BS ISO 11475; brightness to BS ISO 2470; colour to ISO 5631 and opacity to BS ISO 2471.

Testing of all of these properties is included in Smithers Pira's Paper Proficiency Service .

Spot Colour Measurement

Smithers Pira use an X-Rite eXact standard handheld spectrophotometer fitted with a 2mm aperture to measure small area CMYK and spot colours.

The instrument measures CIE L* a* b* and CIE DE*, including CIE DE*2000, and satisfies the requirements of ISO 5-4: 2009 and ISO 13655: 2009.

Applications include assessing colour fade on printed packaging after accelerated light exposure, abrasion resistance and colour staining.

 

EEL 12M Opacimeter

Opacity and whiteness are measured as a percentage using the EEL 12M Opacimeter. An internal microprocessor compares the diffuse reflectance of the sample against black and white references to give opacity.

The EEL Opacimeter is used to measure opacity of plastic using a method based on the Packaging and Industrial Films Association (PIFA) Voluntary Standard 3/79.