CS4020 Liquid Spectrophotometer, Transmission d/0, Micro Volume

COLO.Science · Spectroscopy & Color · Liquid colour measurement

CS4020 Liquid Spectrophotometer — colour of liquids from 1 ml sample volume

The CS4020 liquid spectrophotometer (COLO product code PRO7937) is a liquid colour spectrophotometer for small samples: it measures the colour and spectral transmittance of clear and coloured liquids in a cuvette and reports them as CIE colour values, colour difference to a standard and the liquid colour scales used in specifications — Pt-Co (APHA / Hazen), Gardner, Saybolt, ASTM D1500, pharmacopoeia colour, EBC and ICUMSA. With the micro-volume holder it measures samples from 1 ml and sends data by Bluetooth.

Which instrument?

Routine liquid colour controlCS4010Transmission d/0 · 10 / 50 mm cuvettes · ΔE*ab 0.015Micro volume from 1 mlCS4020Transmission d/0 · ΔE*ab 0.01 · BluetoothLiquids and solidsCS6060Benchtop · reflectance and transmittance

Overview

Fill the cuvette, place it in the compartment and press Test: in about 0.8 s the instrument shows the transmission spectrum, the colour values, the colour difference to the stored standard, the selected colour scale and a pass/fail result. Intelligent zero calibration keeps the results stable through the working day.

Key characteristics

• Transmission d/0 with Ø40 mm integrating sphere, Ø10 mm aperture
• Flat grating and dual 40-element silicon photodiode array, 360–780 nm in 10 nm steps, 0–200 % transmittance
• Liquid colour scales: Pt-Co / APHA / Hazen, Gardner, Saybolt, ASTM D1500, pharmacopoeia colour, EBC, ICUMSA
• Repeatability ΔE*ab 0.01, inter-instrument agreement ΔE*ab 0.2
• Micro-volume holder Ø4 mm in standard delivery — samples from 1 ml
• 7″ capacitive touch screen, 1 000 standards and 10 000 samples, audit trail, USB, serial printer port, Bluetooth

Suitable for

• Solvents, resins, plasticisers and other chemicals — Pt-Co / APHA / Hazen and Gardner colour in incoming and release control
• Oils, fuels and petroleum products — Saybolt and ASTM D1500 colour
• Pharmaceutical solutions — colour against Ph. Eur., USP and ChP colour references
• Food and beverages — beer (EBC), sugar solutions (ICUMSA), juices, syrups, edible oils
• Cosmetic liquids, dyes and clear films or plates in transmission

What is liquid colour measurement for?

The colour of a liquid is one of its specification values. A solvent, a resin, an oil or a pharmaceutical solution leaves production or enters the plant with a colour limit — for example a maximum Pt-Co (APHA / Hazen) value, a Gardner or Saybolt number, an ASTM D1500 colour or a pharmacopoeia colour reference. A change of colour is often the first visible sign of oxidation, thermal damage, contamination, an incomplete purification step or a raw-material change.

Traditionally the sample is compared by eye with reference solutions or coloured glass discs. The result depends on the operator, the light in the room and the tube used, and it cannot be stored as a number with a measured spectrum. A liquid colour spectrophotometer measures the transmission spectrum of the sample and calculates all these scales from it — the same sample gives the same value on every shift and at every site, and the record is kept for audits and certificates.

• Release and incoming control — the colour value on the certificate of analysis measured, not estimated.
• Process monitoring — colour drift of a batch shows a deviation before other tests do.
• One instrument, many scales — Pt-Co, Gardner, Saybolt, ASTM D1500, pharmacopoeia, EBC, ICUMSA and CIE Lab from one measurement.
• Colour difference to a standard — ΔE and pass/fail against the approved batch, under the illuminant and observer your customer specifies.

Liquid colour spectrophotometer or UV/Vis spectrophotometer?

Both instruments send light through a cuvette, but they answer different questions. A UV/Vis spectrophotometer is an analytical instrument: it measures absorbance at selected wavelengths and, through a calibration, the concentration of a substance. A liquid colour spectrophotometer measures the visible transmission spectrum and expresses it as colour — the way the eye sees it under a defined light, and in the colour scales of industry and pharmacopoeia.

If your method prescribes absorbance at a wavelength or a concentration, choose a UV/Vis spectrophotometer; if it prescribes a colour value, a colour scale or a colour difference, the liquid colour spectrophotometer is the right instrument. Many QC laboratories use both.

On the instrument

Cuvette compartmentClosed compartment with holders for 10 mm and 50 mm cuvettes and the micro-volume holder.

Cuvettes 10 · 50 mmLonger path for pale liquids, shorter path for dark ones; 30 and 100 mm on request.

7″ touch screenColour scale, illuminant, tolerances and records set directly on the instrument.

d/0 transmission opticsDiffuse illumination from a Ø40 mm sphere, 0° viewing through the sample.

Measuring and data

Results are stored with the standard and can be printed on the micro-printer or transferred to a PC. The PC quality-management software builds reports and keeps the audit trail; data are transferred by USB, serial printer port, Bluetooth.

For pale liquids (low Pt-Co or Saybolt values) a longer cuvette increases sensitivity; dark liquids such as Gardner-range resins or oils are measured in the 10 mm cuvette.

CS4010 or CS4020 — comparison

Both models share the same benchtop body, d/0 transmission optics with a Ø40 mm sphere, full-spectrum LED, 360–780 nm, 0–200 % transmittance, the same colour scales and indices and the 7″ touch screen. They differ in precision, sample volume and data transfer:

• CS4010 — routine colour control of liquids in 10 mm and 50 mm cuvettes: solvents, oils, fuels, beverages; the economical choice when sample volume is not limited.
• CS4020 — tighter repeatability and inter-instrument agreement for specifications with narrow tolerances, small or expensive samples from 1 ml (pharmaceuticals, fine chemicals, R&D) and wireless data transfer.

Standard delivery

• CS4020 liquid spectrophotometer with 7″ touch screen
• 10 mm cuvette, 50 mm cuvette
• Transmission test holder assembly, micro-volume holder Ø4 mm
• Transmission black board
• Power adapter, data cable; PC quality-management software available for download
• User guide

Options: micro-printer, 30 mm and 100 mm cuvettes. The delivered configuration for a specific order is the one confirmed in the COLO.Science quotation.

Knowledge base

New to colour measurement? Light sources, CIE Lab, ΔE, measuring geometries and transmission measurement of liquids are explained in the Colour Measurement Guide and on COLO.Science, our knowledge base.

Selection guide

• Colour of liquids only: the CS40 liquid colour spectrophotometers — see the comparison above.
• Liquids and also solids, powders or pastes: the CS60 benchtop series with reflectance and transmittance.
• Concentration, absorbance at a wavelength, UV range: a UV/Vis spectrophotometer.
• Not sure which colour scale your customer means? Send us the specification — we confirm the method with the quotation.

Configuration notice

This page is provided for orientation and product selection. The colour scales, cuvettes, accessories and the data you report are confirmed with the official COLO.Science quotation.

Sales and support for international customers

COLO Lab ExpertsPolje ob Sotli 4, SI-3255 Buče, Slovenia
Phone: +386 70 713 437 · Email: sales@colo.si · Web: colo.si
We supply laboratories across Europe directly and through partners. B2B prices are quoted net, excluding VAT.

Replacing visual colour comparison of liquids?

Send us the liquid, the colour scale and the sample volume — we propose the model and confirm it with the quotation.