Examples of SVS Applications
Contamination of Plastic Granules
The Lovibond® SVS with diffusing
optics and a customised test disc are being used to ensure that
contamination of clear plastic granules for moulding drinks
bottles is below acceptable levels. The machinery used in
the production of granules requires regular servicing which,
for a period of time after the service, contaminates the
process so that the granules appear grey instead of white.
It is therefore necessary to run the process and discard
the granules until they reach an acceptable colour. This
check on contamination levels used to involve taking samples to
a laboratory on another part of the site where their colour was
measured on an automatic reflectance colorimeter.
However, the granules manufacturer now uses a Lovibond® SVS
with a test disc containing glass filters which have been
matched to the ideal and just acceptable sample colours.
The instrument is located adjacent to the granules
processing plant and has proved to be a simple yet excellent
method for checking contamination.
Colour Grading of Sewage Sludge Cake as a
Surrogate Measure of Odour
A water company in the UK conducting
research work into the correlation between sewage sludge cake
colour and odour asked us to produce a special disc containing
5 filters which represent samples of sludge cake ranging from
light to dark. The disc was matched in the Lovibond®
Surface Viewing System including viewing optics to diffuse the
surface of the samples.
Dyed Crumb Coating for Food
We produced a special disc for quality
control of dyed bread crumbs used as a food coating. The
disc was matched in the Lovibond® Surface Viewing System including viewing optics
to diffuse the surface of the samples. In the second
application, we were asked to produce a series of customised
glass filters for grading peanut butter. The presence of
chopped peanuts meant that the product had variations in colour
throughout it. As a result, we matched the samples
supplied in a Lovibond® Surface Viewing System with diffusing optics,
allowing the users to view an overall impression of colour
given by the product.
Fine Chemicals
A Scottish research establishment dealing
in fine chemicals needed to grade the colour of two crystalline
yellow products, either in a solid state (the preferred option)
or dissolved in a hazardous organic solvent. The SVS with
diffusing optics was able to provide a colour grading solution
for the samples in a solid state. It was supplied with a set of
customised glass filters ranging from virtually colourless to
straw yellow.
Off-White Detergent Products
A detergent manufacturer in Australia had
been using colour cards under fluorescent laboratory lighting
to grade a range of opaque, off-white detergent products.
Disagreements over colour with a customer, probably due
to discoloration of the cards and a lack of standardised
lighting, prompted the company to seek a more consistent method
of colour control. This has been provided by the Surface
Viewing System with glass filters matched to a selection of
detergent samples.